Archive for the ‘best pcb’ Category

COB immersion gold aluminum substrate, Gold immersion plating

Thursday, August 21st, 2025

COB immersion gold aluminum substrate is a high-power packaging solution that directly bonds the LED chip (Chip On Board) to an aluminum substrate treated with immersion gold.

The aluminum substrate quickly dissipates heat, while the immersion gold layer ensures long-term oxidation resistance of the chip pads, ensuring reliable soldering. This eliminates the need for brackets and reflow soldering, resulting in higher luminous efficacy and longer lifespan. It has become a core substrate for high-power LED modules.

COB immersion gold aluminum substrate, Gold immersion plating

Do you have any questions about COB aluminum PCBs?

Does the immersion gold coating and thermal conductivity meet COB heat dissipation requirements?

Do the dimensions and specifications match COB packaging and lighting fixture installation?

Can the immersion gold process and materials withstand long-term high-temperature use?

Do the performance and cost meet expected price/performance ratios?

BEST Technology’s COB aluminum substrates can answer your questions.

The immersion gold layer reduces contact thermal resistance, while the aluminum base and highly thermally conductive insulation layer quickly dissipate concentrated heat from the COB, ensuring efficient heat dissipation.

The COB package area size and overall shape can be customized to accommodate different power COBs and lamp mounting structures.

The immersion gold layer offers strong oxidation resistance, and the substrate has undergone high-temperature cycling testing without delamination, ensuring it can withstand the long-term high-temperature operating environment of the COB.

High heat dissipation ensures COB lifespan, while customized processing optimizes costs, resulting in a reasonable balance of performance and price.

What is COB aluminum substrate?

COB aluminum substrate is a type of PCB that directly mounts LED chips on an aluminum base. Unlike traditional PCBs that use fiberglass, aluminum substrates use metal for better heat dissipation. This structure ensures LEDs operate efficiently and last longer.

The core of a COB aluminum substrate consists of three layers:

A copper circuit layer for electrical connections.

A dielectric layer for insulation and heat transfer.

An aluminum base layer for mechanical support and thermal conduction.

This design keeps LEDs cool and improves performance. It’s the reason COB substrates are widely used in LED lighting, automotive lights, and high-power applications.

Is immersion gold the same as ENIG?

Yes and no. Immersion gold is a key step in the ENIG (Electroless Nickel Immersion Gold) process. ENIG has two layers: a nickel layer and a thin gold layer. Nickel acts as a barrier to protect the copper, and gold prevents oxidation and ensures good solderability.

Therefore, immersion gold usually refers to the gold layer applied in the ENIG process. This finish is popular because it provides excellent corrosion resistance and long shelf life.

Can you plate aluminum substrate with gold?

Yes, you can. In fact, plating aluminum substrates with gold is common in high-end electronic applications. However, the process is not as simple as plating copper. Aluminum forms an oxide layer quickly, which must be removed before plating.

To apply immersion gold on an aluminum substrate, BEST Technology first coat the aluminum with a conductive layer, usually copper. Then, they apply the ENIG finish on top. This method ensures strong adhesion and reliable performance.

What are the benefits of immersion gold on aluminum substrates?

The benefits are impressive. Here are the main reasons why immersion gold is chosen for COB aluminum substrates:

Superior Corrosion Resistance: Gold does not tarnish or oxidize, so it protects the surface even in harsh environments.

Excellent Solderability: The gold layer makes soldering easier and more reliable, especially for fine-pitch components.

Improved Electrical Performance: Gold has low contact resistance, which enhances signal integrity.

Long Shelf Life: Boards with immersion gold can be stored longer without losing quality.

High Reliability for LED Applications: COB LEDs generate heat, and gold plating helps maintain stable performance under thermal stress.

These benefits make immersion gold plating a preferred choice for high-end LED lighting, automotive electronics, and industrial controls.

How thick is gold in ENIG finish?

The gold layer in an ENIG finish is very thin, but it’s enough to provide excellent protection. Typically, the thickness ranges from 0.05 to 0.1 microns. This thin layer ensures good solderability without adding significant cost.

The nickel layer beneath the gold is thicker, usually around 3 to 6 microns. Together, these layers create a strong barrier that protects the copper from oxidation and maintains good electrical conductivity.

Is ENIG better than HASL?

For high-end applications like COB aluminum substrates, ENIG is better than HASL (Hot Air Solder Leveling). Here’s why:

Flat Surface: ENIG provides a smooth, flat surface, which is essential for small components and fine-pitch designs.

Better Corrosion Protection: Gold offers superior resistance to oxidation compared to HASL.

Higher Reliability: ENIG is more stable for thermal cycling and high-power devices.

HASL is cheaper and works well for simple boards, but for COB LEDs, ENIG is the clear winner.

What are the problems with ENIG solderability?

ENIG is reliable, but there are some challenges:

Black Pad Issue: If the plating process is not controlled, it can lead to corrosion of the nickel layer, causing poor solder joints.

Higher Cost: ENIG is more expensive than HASL or OSP finishes.

However, these issues rarely occur when working with BEST Technology, a trusted PCB manufacturer that follows strict quality controls.

What are the uses of COB aluminum substrate?

COB aluminum substrates are used in a wide range of applications:

LED Lighting: High-brightness LEDs for residential, commercial, and industrial lighting.

Automotive Lights: Headlights, tail lights, and daytime running lights.

Display Backlighting: LCD and signage displays that need uniform light.

Medical Equipment: Devices that require precise lighting and heat management.

Industrial Control Systems: Where stable performance and long life are critical.

These uses show how important COB immersion gold aluminum substrates are in modern technology.

Conclusion:

COB aluminum substrates provide excellent heat dissipation and mechanical strength for LED applications. When paired with immersion gold plating, they offer even greater reliability, corrosion resistance, and solderability. ENIG is better than HASL for high-end boards, and the gold layer, though thin, ensures long-lasting performance.

If you need high-quality COB immersion gold aluminum substrates, contact us today at sales@bestpcbs.com

Tags:COB immersion gold aluminum substrate, gold immersion plating, immersion copper plating, immersion gold on copper, silver immersion plating
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High Frequency PCB Materials, High Frequency Circuit Design

Thursday, August 21st, 2025

Have you ever faced such problems when design a PCB that used in high speed application?

Is your high-speed design bleeding signal strength?
How to solve poor thermal management in high-frequency systems to ensure stability and reliability?
How to effectively suppress severeEMI and meet EMC standards in high-frequency circuits?

At Best Technology, we fabricate high frequency PCB that can solve these problems. We use:

High quality materials with low loss and better shielding performance.
Utilize ground via array, densely arranging ground vias around radiation sources such as microstrip lines to form a “wall”.
Design multi-layer boards and adopt dedicated ground layers through reasonable stack-up design, provide a complete reference ground plane for high-frequency signals.

High frequency PCBs are essential in applications such as automotive radar, aerospace communication, medical imaging, 5G and satellite systems. These boards must handle signals above 100 MHz and, in many cases, well into the GHz range. At such speeds, signal losses, impedance mismatches, and electromagnetic interference (EMI) can cause severe degradation. Best Technology, a leading expertise in high frequency pcb manufacturing, can help to optimize your design and manufacture such board for you!

What is a High Frequency PCB?

A high frequency PCB is a printed circuit board designed to transmit signals above 500 MHz, often extending into 10 GHz, 30 GHz, or even higher depending on the application. Some applications, like automotive radar, require PCBs that perform stably at 77 GHz or more.

These boards are not limited to one sector. They are used in:

Wireless base stations and antennas
Radar for defense and vehicles
Satellite communication modules
High-speed computing and servers
Precision medical imaging devices

The key challenge is that as frequency rises, signals become more vulnerable to losses, reflections, and interference. A standard FR4 PCB cannot handle these issues beyond a certain point, which is why high frequency laminates and designs are essential.

High Frequency PCB Material

The choice of material determines how well a PCB will perform in high frequency environments. Engineers usually evaluate three main parameters:

Dielectric Constant (Dk): This defines how signals propagate through the material. A stable, low Dk improves signal speed and reduces delay.
Dissipation Factor (Df): Also called the loss tangent, this defines how much energy is lost as heat. Lower values are better for long-distance signal transmission.
Thermal Performance: Materials must handle fluctuating temperatures without expansion or deformation, especially in aerospace and automotive environments.

Common Materials Used in High Frequency PCB

PTFE (Teflon-based laminates): Offers extremely low loss and stable dielectric properties. Perfect for microwave and RF circuits, though harder to process during manufacturing.
Rogers laminates: Popular choices like RO4350B and RO3003 are widely used in communication devices due to their balance between cost and performance.
Arlon and Taconic: Trusted for aerospace and military-grade systems.
Ceramic-filled PTFE: Combines the benefits of PTFE with improved thermal stability, suitable for radar and satellite applications.
FR4: Economical, but only practical for low GHz applications, as losses rise sharply at higher frequencies.

When comparing FR4 to Rogers or PTFE, the difference is like comparing regular tires to high-performance racing tires. Both work, but only one is built for extreme conditions.

What is the Best PCB Material for High Frequency?

The “best” material depends on the actual use case. For example:

Up to 3 GHz: Rogers RO4350B provides stable performance at a manageable cost, widely used in RF applications.
Microwave range (10–30 GHz): PTFE laminates such as Taconic TLY or Rogers RO3003 give superior low-loss performance.
5G antennas: Low Dk and Df materials like Rogers RO4835 are chosen for consistent performance in outdoor environments.
Automotive radar (77 GHz): Ceramic-filled PTFE materials are the only reliable solution due to their high thermal and frequency stability.

Cost also matters. PTFE offers the lowest insertion loss but requires advanced processing, increasing manufacturing cost. Rogers materials are easier to fabricate and balance cost and performance, which is why they are widely used.

High Frequency PCB Characteristics

High frequency PCBs stand out due to specific characteristics:

Stable dielectric constant across wide frequencies
Low signal loss
Thermal durability
Controlled impedance
Dimensional stability

These boards are engineered not just to survive but to deliver reliable, repeatable performance in demanding environments.

High Frequency PCB Design Guidelines

Designing a high frequency PCB is a delicate balance of precision, material choice, and layout strategy. Even small mistakes in design can cause significant signal loss, reflection, or interference at gigahertz frequencies. Below are the key guidelines that engineers follow to ensure high performance.

1. Controlled Impedance Design

At high frequencies, the impedance of each trace must be carefully calculated and maintained. Variations in trace width, thickness, or dielectric spacing can cause reflections and signal degradation. Designers usually rely on simulation software to calculate controlled impedance for microstrip, stripline, or coplanar waveguide structures. The target impedance is often 50Ω for single-ended signals or 100Ω for differential pairs.

2. Minimize Trace Lengths

Signal paths should be as short as possible. Long traces increase insertion loss, cause delay, and may introduce unwanted reflections. In applications like RF communication or 5G antennas, even small increases in trace length can degrade signal integrity significantly.

3. Reduce the Number of Vias

Each via acts as a small inductance and capacitance, which can reflect high-frequency signals. Limiting via usage and optimizing via placement is essential. When vias are unavoidable, designers often use via stitching or back-drilling techniques to reduce parasitic effects.

4. Ground Planes and Reference Layers

A continuous, solid ground plane beneath signal traces improves return paths and minimizes electromagnetic interference (EMI). Multiple ground planes can be used in multilayer boards to enhance shielding and reduce noise coupling. Proper stacking ensures that signal layers are adjacent to reference planes, which stabilizes impedance and improves signal quality.

5. Differential Pair Routing

Differential pairs are widely used in high-speed digital and RF circuits. These pairs carry complementary signals, which improves noise immunity and reduces crosstalk. Designers maintain strict control over trace spacing, length matching, and symmetry to preserve signal integrity.

6. Stack-Up Optimization

The stack-up, or layer arrangement, determines how signal layers, power planes, and ground planes interact. Proper stack-up design can reduce cross-talk, improve thermal management, and control impedance. High frequency PCBs often use hybrid stack-ups with PTFE or ceramic layers to balance performance and manufacturability.

Every decision—from material choice to trace width, via placement to ground plane configuration—directly impacts signal integrity. A high frequency PCB is not just about connecting components; it is about managing signals, controlling impedance, and reducing loss to ensure reliable, precise performance in the gigahertz range.

High Frequency PCB Manufacturer – Best Technology

Not all manufacturers are capable of producing high frequency PCBs. Handling PTFE and ceramic materials requires different lamination temperatures, drilling techniques, and plating processes compared with FR4.

At Best Technology, we bring specialized expertise in:

Fabricating Rogers, Taconic, PTFE, and hybrid PCB stack-ups.
Maintaining strict dimensional tolerances for impedance control.
Advanced inspection to measure dielectric thickness, copper roughness, and loss factors.
End-to-end MES traceability to ensure every board can be tracked back to its source materials and processes.

This combination of material knowledge, certified systems, and engineering support makes Best Technology a trusted partner for customers who need more than just a standard PCB.

Insertion Loss Comparisons of Common High Frequency PCB Constructions

Material	Frequency (10GHz)	Insertion Loss (dB/inch)	Notes
FR4	~10GHz	0.7 – 1.0 dB	High loss, not recommended
Rogers RO4350B	~10GHz	0.2 – 0.3 dB	Cost-effective, reliable
Rogers RO3003	~10GHz	0.1 – 0.15 dB	Excellent for microwave use
PTFE Ceramic	~10GHz	0.05 – 0.1 dB	Premium choice for radar/5G

This table clearly shows why FR4 is avoided for RF designs. At high GHz levels, FR4 can lose more than three times the signal strength compared with PTFE laminates.

High Speed vs High Frequency PCB – What is the Difference?

The terms “high speed” and “high frequency” are often confused, but they describe different challenges:

High Speed PCB: Concerned with digital signals, rise times, and data rates. Examples: DDR memory boards, data centers, and Ethernet.
High Frequency PCB: Concerned with analog and RF signals in the GHz range. Examples: radar, antennas, and satellite communication.

In practice, many designs overlap. For instance, a 5G base station board must support high-speed data processing and high-frequency RF transmission simultaneously. This is why engineers often require both high-speed and high-frequency design expertise.

High Speed vs High Frequency PCB – What is the Difference?

Why Do We Need High Frequency?

High frequency PCBs enable many of the technologies that define modern life:

5G base stations and smartphones: Delivering ultra-fast, low-latency communication.
Automotive radar: Assisting advanced driver-assistance systems and autonomous driving.
Satellite communication: Providing global coverage for navigation and broadcasting.
Defense and aerospace: Supporting secure, high-performance radar and communication systems.
Medical devices: Enabling accurate imaging through MRI, CT, and ultrasound.

Without these boards, the next generation of communication and smart systems would not be possible.

Who Should Not Get High Frequency?

Not every project needs high frequency PCBs. For example:

A consumer product with simple sensors may not justify the extra cost.
Low-speed devices below 500 MHz can rely on FR4.
Cost-sensitive projects without high bandwidth needs should avoid high frequency laminates.

Choosing the right PCB type should always balance performance needs vs. budget.

FAQs

1. What frequency is considered high frequency in PCBs?

Any PCB designed to work above 500 MHz is typically considered high frequency, with advanced boards operating up to 60 GHz or more.

2. How does dielectric constant affect PCB performance?

A stable dielectric constant ensures signals propagate at predictable speeds and maintain impedance control, crucial for RF circuits.

3. Can FR4 be used for high frequency PCB?

FR4 works only up to around 1 GHz. Beyond that, losses become too high for reliable performance.

4. What are the challenges in manufacturing high frequency PCB?

Processing PTFE materials, achieving impedance accuracy, reducing insertion loss, and handling copper roughness are common challenges.

5. How to reduce signal loss in high frequency PCB design?

Use low-loss laminates, design shorter traces, avoid unnecessary vias, and apply smooth copper surfaces to reduce resistance.

Tags:high frequency pcb, high frequency pcb materials, high frequency vs high speed pcb
Posted in best pcb, bestpcb, Design Guide, FAQ, RF Board | No Comments »

Copper Multilayer PCB Manufacturer in China| Best Technology

Wednesday, August 20th, 2025

What is copper multilayer PCB? Let’s discover its material, benefits, applications, design guide for wearable device, production process through this blog.

Are you troubled with these problems?

High-frequency signal degradation killing your design?‌
Heat dissipation always a bottleneck?‌
Yield rates dropping with layer stacking?‌

Best Technology can provide service and solutions‌:

Rapid Response‌ – 24/7 engineering support, samples delivered in 48 hours.
Cost Efficiency‌ – Intelligent panelization + material reuse cuts costs by 15%.
‌Transparency‌ – Real-time production tracking with photo verification at key stages.

Welcome to contact us if you have any inquiry for copper multilayer PCB: sales@bestpcbs.com.

What is Copper Multilayer PCB?

Copper Multilayer PCB consist of alternating copper conductive layers and insulating materials (such as FR-4 or polyimide) bonded together through a lamination process. Copper’s high thermal conductivity (386W/m·K) and electrical conductivity support complex circuit designs, enabling high-density interconnection between layers through through-holes, blind vias, or buried vias.

This type of PCB is suitable for high-power applications (such as automotive electronics and 5G base stations), offering superior heat dissipation and signal stability compared to single- or double-layer PCBs. Its symmetrical structure (e.g., copper-prepreg-core-prepreg-copper) enhances mechanical strength and controls impedance. Some models also utilize thermal isolation technology to directly conduct heat.

What is Material of Multilayer Copper PCB?

1. Conductive Layer

Composition: Electrolytic copper foil (ED) or rolled copper foil (RA)
Features: Thickness 0.5–6 oz/ft² (17–210 μm), conductivity ≥58 MS/m (20°C), surface finish available: brown oxide (OSP) or nickel-gold (ENIG).

2. Insulation

FR-4: Epoxy resin + fiberglass, dielectric constant 4.2–4.8 (1 GHz), heat resistance 130°C (standard) / 170°C (high Tg).
Polyimide (PI): Dielectric constant 3.4–3.6 (1 GHz), heat resistance >250°C, short-term temperature resistance ≥300°C.

3. Prepreg (PP)

Composition: 7628/2116/1080 glass cloth impregnated with epoxy resin
Features: Thickness 0.05–0.2mm (0.1–0.4mm after lamination), resin content 52%–65%, curing conditions 180°C/60min.

4. Metal Substrate (Optional)

Aluminum Substrate: 1050/6061 alloy, thermal conductivity 180–220 W/m·K, thickness 1.0–3.2mm.
Copper Substrate: Electrolytic copper, thermal conductivity 386 W/m·K, thickness 0.5–2.0mm.

5. High-Frequency Material (Optional)

PTFE: Polytetrafluoroethylene, dielectric constant 2.2–2.5 (10 GHz), dissipation factor <0.001 (10 GHz).
Rogers RO4003C: dielectric constant 3.38 (10 GHz), dissipation factor 0.0027 (10 GHz).

6. Solder Mask

Composition: Liquid Photosensitive Solder Mask Ink (LPI)
Characteristics: Thickness 10–25μm, Temperature Resistance ≥ 150°C (short-term), Insulation Resistance ≥ 1×10⁸Ω.

What Are Advantages of Copper Multilayer PCBs?

Benefits of copper multilayer PCB:

High-density integration capabilities: By stacking multiple conductive layers (up to 32 layers), complex circuits can be integrated within a limited space, meeting the demands of miniaturized devices such as smartphone motherboards.
Excellent heat dissipation performance: Copper foil has a thermal conductivity of 400. W/m·K (nearly twice that of aluminum substrates), combined with a thick copper design (3–10 oz), allows for rapid heat conduction and reduces the junction temperature of high-power devices.
High-frequency signal integrity: Specialized high-frequency materials (such as PTFE) have a dielectric constant as low as 2.2–3.5, reducing signal loss and making them suitable for 5G base stations and radar systems.
Optimized electromagnetic compatibility: Multi-layer ground and power planes effectively shield electromagnetic interference (EMI) and reduce crosstalk risks.
Improved mechanical strength: Copper substrates offer superior deformation resistance to traditional FR-4, making them suitable for vibration environments such as automotive electronics.
Current carrying capacity: Thick copper layers (6 oz+) support high current transmission and reduce voltage drop in power modules.
Design flexibility: Supports advanced processes such as blind and buried vias and mixed dielectric layers to meet the needs of high-frequency, high-speed, and high-power hybrid designs.
Long-term reliability: Copper’s oxidation resistance and multi-layer laminate structure (using prepreg PP) extend product life, making them suitable for industrial control equipment.

What Are Advantages of Copper Multilayer PCBs?

What Are Applications of Copper Multilayer PCB?

Communications Equipment: 5G base stations, routers, mobile phone signal repeaters, fiber optic receivers
Computers and Data Centers: Server motherboards, hard drive controllers, graphics cards, storage devices
Medical Equipment: Heart monitors, CT scanners, X-ray equipment
Industrial Control and Automotive Electronics: Motor controllers, industrial automation systems, power converters, in-vehicle electronics
Aerospace: Satellite systems, space exploration equipment, radar
Consumer Electronics: Smartphones, wearable devices, game consoles
Energy and Power Systems: Power amplifiers, battery chargers, rectifiers, high-power conversion devices

How to Design a Copper Multilayer PCB for Wearable Device?

1. Material Selection & Substrate Optimization

Substrate: Prioritize polyimide (PI) or liquid crystal polymer (LCP), thickness 0.05–0.1mm, for flexibility (bending radius <5mm) and high-temperature resistance (Tg >250℃).
Conductive Layer: Use ultra-thin rolled annealed copper foil (RA, 0.5oz/17μm) to balance flexibility and conductivity (conductivity ≥58 MS/m).
Adhesive Layer: Apply low-modulus prepreg (PP) to reduce interlayer stress and prevent cracking during bending.

2. Stackup Design & Flexibility

Layer Count: Prioritize for 4-layer boards (Signal-Ground-Power-Signal) with total thickness 0.4–0.6mm to minimize weight.
Symmetry: Distribute copper layers symmetrically (e.g., Cu-PI-Cu) to avoid warping during bending; place ground and power planes adjacent to reduce EMI.
Flexible Zones: Use coreless structures (copper foil + PI only) in bending areas (e.g., wristband connections) for unrestricted flexibility.

3. Signal Integrity Assurance

High-Speed Signals: Design Bluetooth/Wi-Fi antennas as microstrip lines with 50Ω impedance control (trace width 0.15mm, spacing 0.1mm) and avoid 90° bends.
Differential Pair Routing: Route high-speed interfaces (USB, MIPI) with equal length (tolerance ±5mil) and spacing ≥3x trace width to minimize crosstalk.
Shielding: Add copper shielding layers (width ≥2mm) around antennas, grounded via stitching to reduce external EMI.

4. Power Distribution & Low-Power Design

Layered Power: Implement split power planes (e.g., 1.8V/3.3V) with power-ground spacing 0.1mm and decoupling capacitors (10μF + 100nF).
Low-Power Components: Select ultra-low-power MCUs (e.g., STM32L series) and PMICs, paired with hardware watchdogs to prevent lockups.
Layout Optimization: Place batteries, PMICs, and MCUs close to minimize trace length and reduce static power consumption.

5. Thermal Management Strategies

Heat Dissipation: Place copper foils (1oz thickness) under heat-generating components (MCUs, power chips) and connect via thermal vias (diameter 0.2mm, pitch 0.5mm) to external thermal areas.
Thermal-Electric Separation: Isolate high-power LEDs or battery chargers with dedicated copper layers to prevent heat transfer to sensitive components.
Material Enhancement: Embed graphene thermal films (0.01mm thickness) in critical zones to improve lateral heat conduction.

6. Mechanical Reliability & Bend Resistance

Solder Mask: Use high-flexibility solder mask (e.g., Taiyo PSR-9000), thickness 10μm, rated for >100,000 bend cycles.
Surface Finish: Apply ENIG (Electroless Nickel Immersion Gold) or OSP (Organic Solderability Preservative) to prevent copper oxidation and ensure solder reliability.
Validation: Pass dynamic bend tests (radius 3mm, 1Hz frequency, 10,000 cycles) and accelerated aging (85℃/85%RH, 168 hours).

7. Electromagnetic Compatibility (EMC) & Compliance

Grounding: Connect metal enclosures (e.g., wristband, buttons) to PCB ground via spring contacts or conductive adhesives, forming a Faraday cage to mitigate ESD.
Certification: Achieve CE (EU) or FCC (US) EMC compliance, testing across 80MHz–6GHz to ensure stable operation in complex electromagnetic environments.
Wireless Charging: Position Qi-standard coils at PCB edges, away from antennas and sensors to avoid interference.

How to Design a Copper Multilayer PCB for Wearable Device?

How was Copper Multilayer PCB Made?

1. Substrate Preparation

Select FR4 glass fiber epoxy resin laminate as substrate, with copper foil cladding (thickness 1oz/2oz).

2. Inner Layer Pattern Transfer:

Apply photosensitive dry film, transfer circuit pattern via UV exposure, and dissolve unexposed areas.
AOI (Automatic Optical Inspection) verifies line precision and marks defects.

3. Inner Layer Etching & Oxidation

Chemically etch copper not protected by dry film to form inner layer circuits.
Black oxide/brown oxide treatment on copper surfaces to enhance interlayer adhesion.

4. Lamination & Pre-Press

Stack inner layer core boards, prepreg sheets, and outer layer copper foils alternately, aligning via positioning holes.
High-temperature/high-pressure lamination (180-200℃) melts resin to fill gaps, forming a unified board.

5. Mechanical Drilling

CNC drilling machine processes through-holes/blind holes with diameter accuracy ±0.05mm.
Clean hole-wall resin residues (desmear).

6. Electroless Copper Plating

Deposit electroless copper (0.3-0.8μm) on hole walls to establish conductive base.
Electroplate to thicken copper layer (20-25μm) for reliable hole-wall conductivity.

7. Outer Layer Pattern Transfer

Repeat inner layer pattern transfer process, addressing hole alignment.
Use high-precision exposure equipment to compensate for interlayer deviation.

8. Outer Layer Etching & Stripping

Secondary etching defines outer layer circuits, with tin layer protecting desired copper areas.
Alkaline solution strips dry film, retaining circuit patterns.

9. Solder Mask & Silkscreen

Apply liquid photosensitive solder mask (green/black), expose and develop to expose pads.
Silkscreen component identifiers (white/yellow text).

10. Surface Finish

Treat pad areas with ENIG (Electroless Nickel Immersion Gold)/immersion tin/OSP to prevent oxidation and enhance solderability.
Plate gold finger areas with hard gold for wear resistance (e.g., board-edge connectors).

11. Electrical Testing

Flying probe test or bed-of-nails test verifies continuity and insulation.
AOI re-inspects for micro-shorts/opens.

12. Profiling & Packaging

CNC milling cuts board outlines; V-score or punching for separation.
Final cleaning, drying, and vacuum moisture-proof packaging.

Why Choose Best Technology as Copper Multilayer PCB Manufacturer?

Reasons why choose us as copper multilayer PCB manufacturer:

19 years of experience in copper substrate R&D: Precisely addressing interlayer heat dissipation and current carrying challenges in high-power multi-layer copper substrates, ensuring long-term stable operation of high-power devices (such as projectors/lasers).
Triple international quality certification (ISO9001/IATF16949/ISO13485): Medical and automotive-grade copper substrate production standards ensure ±1μm copper thickness uniformity in multi-layer board holes and zero deviation in electrical performance.
Customized thermal management solutions for copper substrates: Embedded copper pillars/thermoelectric separation structures reduce the thermal resistance of multi-layer boards to 0.5°C/W, extending the life of LEDs/power modules by over 30%.
Cost-optimized copper substrate design: Utilizing a gradient copper foil thickness (1oz outer layer + 2oz inner layer) to balance conductivity and heat dissipation requirements, saving 15% in material costs compared to traditional designs.
24-hour copper substrate rapid prototyping service: Laser drilling and electroless copper plating processes deliver high-complexity (20+ layers) copper substrate prototypes within 48 hours, accelerating the validation cycle for high-power products.
Free Copper Substrate Design for Material (DFM) Analysis: Preemptively identify design risks such as copper layer distribution and blind via alignment, preventing interlayer cracking caused by thermal expansion coefficient mismatch and reducing secondary re-board rework costs.
100% Automated Optical Inspection (AOI): Detects hole wall voids and copper nodules, a common feature of copper substrates, with a 0.01mm² level of defect detection, ensuring zero defective batch orders.
Full-Process Copper Substrate Solution: From thermal simulation (Flotherm) to copper layer etching and surface treatment (ENIG/HASL), we provide a one-stop service, reducing the cost of coordinating multiple suppliers.
Ultra-Thin Copper Substrate Process (0.2mm total thickness): Combining flexible PI substrate and copper foil calendering technology, we achieve a bend radius of less than 1mm for multi-layer copper substrates for wearable devices while maintaining a current density of 10A/cm².

Our Copper PCB Capabilities

Items	Technical Parameters
Product model	Copper PCB
Copper trace thickness	1OZ, 2OZ, 3OZ, 4OZ, up to 10OZ
Thermal Conductivity	1.0, 1.5, 2.0, 3.0W/m.K
Surface finishing	HAL(LF)/ Gold Immersion/ Gold plating/ OSP/ Immersion Tin/ Silver Immersion
Soldermask Color	White/Black/Green/Blue/Red/Yellow
Layers	1L, 2L, 4L, 6L, 8L, double sided, COB
Maximum dimension	1,100mm*480mm; 1,500x300mm
Minimum dimension	5mm*5mm
Minimum Line width/space	0.1mm/0.1mm
Warp and twist rate	≤0.75%(thickness:1.6mm, measurement:300mm×300mm)
Board Thickness	0.3－4.5mm
Die-Punching dimension tolerance	±0.15mm
V-cut positioning tolerance	±0.1mm
Manufacturing capability	6000m²
Wall Cu thickness	15-25um
Alignment tolerance	±0.076mm
Minimum diameter of die-punching hole	Thickness <=1.0mm: 1.0mm
	Thickness 1.2-3.0mm: 1.5mm
	Thickness 4.0mm: 2.0mm
Minimum size the square groove/slot/cutout	Thickness <=1.0mm: 0.8mm×0.8mm
	Thickness 1.2-3.0mm: 1.0×1.0mm
	Thickness 4.0mm: 1.5×1.5mm
Outline Tolerance	CNC routing：±0.1mm; Die-punching：±0.15mm
Minimum diameter of hole	0.3mm; not limit for maximum diameter of hole
Surface Finishing Thickness	gold plating：Ni 2.5-5um, Au: 0.025－0.075um
	immersion gold: Ni 3-6um, Au: 0.025-0.1um
	HAL(LF): 3-30um
V－cut Angle tolerance	±5°
V-cut Range	0.3mm-4.5mm
Smallest silkscreen height	0.15mm
Smallest PAD	0.1mm

How to Get a Quote for Copper Multilayer PCB Project?

Essential Documentation for Copper Multilayer PCB Quotation

Lamination Stackup Drawing: Specify layer materials (e.g., FR-4/Rogers 4350), copper thickness (1–6OZ), dielectric thickness (mm), and impedance control targets.
Gerber Files: Include circuit layers, drilling layers, and solder mask layers. Annotate trace width/spacing (e.g., 4/4mil), blind/buried via positions, and hole tolerance (±0.05mm).
PCB Technical Parameter Sheet: Board dimensions (L×W×T), layer count (e.g., 8L), surface finish (ENIG/OSP), and special processes (via plating/half-hole).
Impedance Control Requirements: Define differential pair impedance (e.g., 100Ω±10%), reference layers, and testing methods.
Acceptance Criteria: Specify IPC class (e.g., IPC-6012 Class 3) and testing items (flying probe/AOI/X-ray).
Quantity & Lead Time: Prototype/batch quantity (e.g., 5pcs/1k) and desired delivery timeline (e.g., 7-day expedited).
Special Requirements: High-frequency/thermal needs (e.g., PTFE hybrid), environmental certifications (RoHS/UL).

Why Partner with Best Technology?

Expertise: Handles 16+ layer thick copper (6OZ) and hybrid high-frequency boards.
Speed: Offers 48-hour quick quotes and complimentary impedance calculation.
Quality: Free DFM review to eliminate design flaws upfront.
Result: Avoid cost overruns, accelerate time-to-market, and ensure compliance for demanding applications.

Welcome to contact us if you have any request for copper multilayer PCB: sales@bestpcbs.com.

Tags:Copper Multilayer PCB, Multilayer Copper PCB
Posted in best pcb, bestpcb, mcpcb, Metal Core PCB | No Comments »

High Frequency PCB Design Guidelines – RF PCB Basic Acknowledge

Wednesday, August 20th, 2025

Are you often curious about these questions about high frequency PCB?

Have you ever wondered why some electronic systems lose performance at higher frequencies?
Why a well-designed PCB for low-speed circuits often fails when pushed into GHz ranges?
How can designers minimize losses above 1 GHz?

The answer lies in the design of high frequency PCBs. High frequency PCBs also known as RF PCB or radio frequency pcb. They are more important in applications such as 5G, automotive radar, aerospace communication, medical imaging, and satellite systems. These boards must handle signals above 100 MHz and, in many cases, well into the GHz range. At such speeds, signal losses, impedance mismatches, and electromagnetic interference (EMI) can cause severe degradation.

This blog provides detailed guidelines for designing high frequency PCBs. From material selection to signal routing, impedance control, thermal management, and testing, we will walk through the critical factors engineers must consider.

What Frequency Range is Considered High Frequency in PCB Design?

In PCB engineering, high frequency generally refers to signal frequencies above 500 MHz. For RF and microwave circuits, the range extends from 1 GHz up to 100 GHz. Typical applications include:

Wi-Fi (2.4 GHz / 5 GHz)
Bluetooth (2.4 GHz)
5G NR bands (3.5 GHz / 28 GHz / 39 GHz)
Automotive radar (24 GHz / 77 GHz)
Satellite communication (Ku-band 12–18 GHz, Ka-band 26–40 GHz)

The higher the frequency, the more sensitive the PCB becomes to signal loss, dielectric constant stability, and copper surface roughness. For instance, at 28 GHz (5G mmWave), even 0.1 dB/cm of insertion loss can cause serious degradation in system performance.

High Frequency PCB Design Guidelines - RF PCB Basic Acknowledge

What PCB Materials are used for High Frequency Applications?

The dielectric substrate is the foundation of high frequency PCB design. Key material properties include:

Dielectric Constant (Dk): Should remain stable across frequency and temperature.
Dissipation Factor (Df): Lower values mean lower signal loss.
Thermal Conductivity: Crucial for high-power RF designs.

Common Materials for High Frequency PCBs

Material Type	Dielectric Constant (Dk)	Dissipation Factor (Df) @10GHz	Thermal Conductivity (W/m·K)	Typical Use Case
FR4 (High Tg)	4.2–4.7	0.020–0.025	0.3	<1 GHz, low-cost boards
Rogers RO4350B	3.48 ±0.05	0.0037	0.69	2–20 GHz, antennas
Rogers RO3003	3.00 ±0.04	0.0013	0.50	mmWave 5G (28 GHz, 39 GHz)
Taconic RF-35	3.50	0.0018	0.62	Microwave circuits
PTFE (Teflon)	2.1–2.6	0.0009–0.0015	0.25–0.30	Aerospace, radar
Ceramic-filled PTFE	3.0–10	0.001–0.005	0.7–1.2	High-power RF

Data comparison shows that Rogers RO3003 has one of the lowest Df values, making it widely used in 5G mmWave base stations. PTFE-based laminates dominate satellite and radar applications where extreme performance is required.

How Does Dielectric Constant Affect Signal Speed?

The dielectric constant (Dk) directly influences the propagation velocity of signals on PCB traces. The relation is:

Where c = 3 × 10^8 m/s (speed of light in vacuum).

For FR4 (Dk ≈ 4.5) → v ≈ 1.41 × 10^8 m/s
For Rogers RO4350B (Dk ≈ 3.48) → v ≈ 1.61 × 10^8 m/s
For PTFE (Dk ≈ 2.2) → v ≈ 2.02 × 10^8 m/s

This means PTFE substrates allow signals to travel ~43% faster than FR4. In high-speed digital systems (like SerDes 56G PAM4 links), such differences greatly influence timing margins.

What are the Key Design Rules for High Frequency PCB Layout?

Designing high frequency boards requires stricter rules compared to conventional PCBs:

1. Controlled Impedance Traces

Single-ended 50 Ω, differential 90–100 Ω are typical.
Impedance tolerance must be within ±5% for frequencies above 10 GHz.

2. Insertion Loss Minimization

Use smooth copper foils (Ra < 2 μm).
Keep transmission lines short.
Avoid unnecessary vias, which can introduce 0.1–0.2 dB loss per via at 10 GHz.

3. Ground Plane Integrity

Solid reference planes reduce return path discontinuities.
Use via fences to confine RF energy.

4. Crosstalk Reduction

Maintain spacing ≥3× trace width between high frequency lines.
Place sensitive analog circuits far from digital noise sources.

5. Thermal Management

For power amplifiers, substrates with >0.8 W/m·K thermal conductivity are recommended.
Use thermal vias under RF components for efficient heat dissipation.

What are the Key Design Rules for High Frequency PCB Layout?

How Thick should a High Frequency PCB be?

The thickness of the PCB substrate directly impacts impedance and signal integrity. Typical stack-up configurations:

PCB Thickness	Layer Count	Dielectric Thickness	Frequency Application
0.2–0.4 mm	2–4L	0.1 mm core	High-speed connectors, 10–20 GHz
0.6–0.8 mm	4–6L	0.2 mm core	2.4/5 GHz Wi-Fi, Bluetooth
1.0–1.6 mm	6–10L	0.3–0.5 mm core	Automotive radar, 24 GHz
2.0+ mm	8–12L	>0.5 mm core	28 GHz 5G, satellite boards

For example, in 77 GHz automotive radar PCBs, manufacturers often use 0.254 mm or thinner substrates to reduce dielectric loss and keep microstrip lines narrow enough for impedance control.

How to Reduce Signal Loss in High Frequency PCB Design?

Signal loss (attenuation) is one of the biggest concerns in high frequency circuits. It is affected by:

Dielectric Loss: Higher Df increases insertion loss.
Conductor Loss: Surface roughness increases resistance at high frequencies due to skin effect.
Radiation Loss: Poor layout or sharp bends radiate energy.

Example of Insertion Loss Data

Material	Frequency	Line Length	Insertion Loss
FR4 (Df 0.020)	10 GHz	10 cm	-1.2 dB
Rogers RO4350B	10 GHz	10 cm	-0.25 dB
PTFE (Df 0.001)	10 GHz	10 cm	-0.05 dB

This demonstrates why high frequency applications almost never rely on standard FR4.

In Conclusion

Designing a high frequency PCB requires more than standard PCB know-how. From material selection to impedance control, routing, thermal management, and advanced testing, every step must be carefully engineered.

Best Technology is a trusted PCB manufacturer in China with expertise in high frequency PCB fabrication. We offer advanced laminates like Rogers, Taconic, and Isola, alongside ISO9001, ISO13485, IATF16949, and AS9100D certifications. Our team applies rigorous quality control, competitive pricing, professional engineering support, and MES-based traceability to deliver reliable high frequency PCBs for industries such as 5G, automotive radar, medical devices, and aerospace.

If your project requires precise high frequency PCB solutions, Best Technology is ready to provide professional guidance and manufacturing excellence.

FAQs

1. Can FR4 be used for high frequency PCBs?

Yes, but only for frequencies below ~1 GHz. For anything higher, specialized laminates are required.

2. What is the most commonly used material for 5G PCBs?

Rogers RO4350B and RO3003 are widely adopted due to their low loss at mmWave bands.

3. How do vias affect high frequency performance?

Each via can add 0.1–0.2 dB loss at 10 GHz, so designers minimize via count in RF paths.

4. Why is surface roughness important?

At high frequencies, the skin effect confines current to the outer conductor surface. Rough copper increases resistance and loss.

Tags:high frequency pcb, high frequency pcb design guide, radio frequency pcb, RF PCB
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Copper Pour PCB, Copper Pour in PCB

Wednesday, August 20th, 2025

What is copper pour PCB? Let’s discover its function, application, clearance design rules, grounding and connection problems and solutions, dead zones and sharp problems and solutions.

Are you worried about these problems?

Why does my high-speed PCB always have signal integrity issues?
How can I reduce thermal hotspots in dense component layouts?
What’s the most cost-effective way to improve EMI performance?

Best Technology can provide service and solutions:

Optimized copper pour design: Reduces impedance discontinuities and crosstalk by providing uniform current paths.)
Thermal-balanced copper pour: Dissipates heat evenly through enhanced thermal conductivity.)
EMI-shielded copper pour: Acts as a natural Faraday cage to minimize radiated emissions.)

Welcome to contact us if you have any request for copper pour PCB: sales@bestpcbs.com.

What is Copper Pour PCB?

Copper pour PCB (also called as copper pour in PCB) design refers to the technique of filling unused areas on a circuit board with conductive copper, typically connected to ground or power networks. It involves filling blank areas of a circuit board (not layout traces) with a continuous layer of copper foil using polygonal fills automatically generated by the design software. These copper foil areas are typically connected to the board’s ground plane (GND) or power plane (VCC), forming a complete conductive layer.

What is the Purpose of the Copper Pour on a PCB?

Signal Integrity: Provides low-impedance return paths for high-frequency signals, reducing electromagnetic loss.
EMI/RFI Shielding: Acts as conductive shielding to suppress external/internal electromagnetic interference.
Thermal Dissipation: Enhances heat transfer from high-power components via copper’s thermal conductivity.
Power Stability: Stabilizes voltage delivery through low-inductance copper planes for high-current circuits.
Structural Integrity: Balances copper distribution to prevent board warpage during fabrication.
Cost Efficiency: Reduces production costs by minimizing copper etching waste and simplifying processes.
Impedance Matching: Enables precise impedance control for high-speed signals via ground plane integration.

What Are Applications of Copper Pour PCB?

Lighting Systems: LED streetlights, automotive lights, surgical lighting.
Automotive Electronics: Electric vehicle battery management, motor controllers, charging systems, and headlight drivers.
Communications Equipment: 5G/6G base stations, RF amplifiers, antenna modules, and filtering devices.
Industrial Equipment: Welding machines, solar inverters, UPS power supplies, and robotic control systems.
Medical Equipment: MRI systems, X-ray machines, and surgical laser equipment.
Computers and Consumer Electronics: CPU motherboards, game consoles, and smartphones.
Aerospace: Satellite communications, radar, and avionics equipment.

What is the Difference between Copper Pour and Trace?

Characteristic	Trace	Copper Pour
Definition	Conductive path for signal/current	Filled copper area for functional/thermal purposes
Function	Signal/current transmission	Heat dissipation, EMI shielding, high-current carrying
Smart Avoidance	None (manual adjustment required)	Auto-isolates from other networks
Design Method	Manual routing line by line	Auto-fills irregular regions
Short Circuit Risk	Low (independent path)	High for standard pour, low for filled pour
High-Frequency Adaptability	Susceptible to interference (requires width/spacing optimization)	Reduces crosstalk (avoids via resonance)
Typical Thickness	0.7 mil (½ oz) or 1.4 mil (1 oz)	4 mil (standard)

PCB Copper Pour Clearance Design Rules

1. Core Spacing Values

General Baseline: Copper pad to pad/via distance ≥0.2mm (1oz copper foil) or ≥0.33mm (2.5oz copper foil). Any distance below this will result in a short circuit.
High-voltage scenarios: Calculate clearance based on voltage (e.g., 220V requires ≥2.5mm), using the maximum of clearance and creepage distances.
Board Edge Treatment: Copper pad to cutting line ≥0.8mm; otherwise, the copper sheet may tear during milling.

2. Specific Scenarios

Under capacitors: Copper pads are strictly prohibited, with a spacing of 0.1mm (to prevent parasitic capacitance from interfering with signals).
Antenna Area: Clearance below wireless modules ≥12.5mm (to prevent signal coupling, measured values).
Gold-plated board edges: Copper pad setback ≥0.5mm (to prevent corrosion caused by plating solution infiltration).

3. Software Practice (AD/KiCad)

Rule Settings:

Global Spacing: Start at 0.5mm (20mil), with separate rules for high-voltage areas.
Copper Pad Specific: Set to 0.8mm when no solder mask is present (to facilitate repair and soldering).
Priority Suppression: Board-Level Rules > Net-Level Rules > Single-Object Rules. In case of conflict, the strictest value is used.

4. Manufacturing Minefields

Peelable Structures: Isolated copper islands in the copper pad with a width less than 0.2mm will be deleted (etching will cause breakage).
Copper Layer Text: Text must be ≥0.15mm away from the copper pad (otherwise, the silkscreen will be blurred).
Sharp Angle Prohibition: Copper pad corners must be ≥45° (sharp corners can cause excessive corrosion during acid etching).

5. Signal Terms

High-Speed Lines: Copper pads must be ≥3 times the line width away from clock lines (e.g., a 0.2mm line width requires a 0.6mm setback).
Grounding copper: The spacing between copper layers in different voltage domains should be ≥1mm (to prevent leakage current).

Dead Zones and Sharp Angles Problems in Copper Pour PCB Design

Dead Zone Problems:

1. Electrical Isolation Failure: Isolated copper areas not connected to the network (dead copper) create an antenna effect, increasing electromagnetic interference (EMI), causing high-frequency signal distortion or noise interference.

2. Thermal Stress Concentration: Dead copper cannot effectively dissipate heat, causing local overheating that accelerates component aging and shortens PCB life.

3. Manufacturing Defect Risk: Dead copper can easily peel during etching, causing shorts or opens.

Dead Zone Solutions:

1. Ground Via Connection Design: Add ground vias (vias) in large dead copper areas, connecting them directly to the ground network (recommended density ≥ 1 per square centimeter) to eliminate the antenna effect.

2. Copper Layer Optimization Strategy: Avoid copper pouring in unrouted areas (such as mid-layer routing openings); use a grid-like window design (heat dissipation vias) to improve heat dissipation.

3. Automated Design for Factoring (DFM) Checking: Use EDA tools to run DFM rule checks (e.g., Gerber files with board outlines) to automatically identify and remove dead copper areas.

Sharp Angle Problems:

1. Enhanced EMI Radiation: Sharp angles (≤90°) form high-frequency transmitting antennas, interfering with sensitive circuits such as clock signals and increasing signal noise.

2. Etchant Traps: Etching solution accumulates at sharp angles, unevenly corroding the copper layer and causing wire breaks or shorts (the risk is doubled for trace widths ≤5 mils).

3. Mechanical Fragility: Sharp angles are susceptible to fracture under thermal stress, leading to open circuit failures, which is particularly serious in industrial-grade PCBs.

Sharp Angle Solution:

1. Replacement of Curved Corners: Use 45° bevels or arcs (arc radius ≥ 2 times the trace width) for all trace turns, completely avoiding 90° angles.

2. Line Optimization: Widen high-voltage/high-frequency lines (e.g., power lines ≥ 20 mils), ensuring smooth, chamfer-free lines; prioritize large-area copper pours for ground lines.

3. Embed Design for Functional Measurement (DFM) rules: Set minimum bend radius (≥ 0.2 mm) and line-to-space ratio (≥ 1:1), and use EDA tools to automatically correct sharp angles.

Grounding and Connection Problems in Copper Pour PCB Design

1. Grounding Failure Causing Noise/EMI Problems:

Ungrounded copper areas act as EMI antennas.
Long/impedance-mismatched ground paths disrupt high-frequency signal return.

Grounding Failure Causing Noise/EMI Solution:

Auto-connect copper to GND in Altium, use via stitching to link top/bottom copper to inner ground planes.
Limit high-frequency signal return paths to ≤ λ/20.
Use 4-layer stackup (Sig/Gnd/Pow/Sig) for direct top/bottom-to-ground connections.

2. Copper-Via/Pad Disconnection Problems:

Thermal stress or manufacturing errors break copper-via/pad links.
Flex PCBs develop cracks in bent areas.

Copper-Via/Pad Disconnection Solution:

Add teardrop transitions at vias to increase contact area.
Use edge-plating for flex PCBs with prepreg reinforcement.
Confirm min. copper thickness (≥1oz) and via spacing (≥0.3mm) with fabricators.

3. High-Frequency Loop Interference Problems:

Copper loops cause magnetic coupling, inducing crosstalk/oscillation.
Asymmetric differential pair returns disrupt impedance matching.

High-Frequency Loop Interference Solution:

Isolate analog/digital grounds with beads/0Ω resistors; connect copper to single GND.
Add guard ground traces (≥3× line width) around differential pairs.
Optimize copper shapes via SIwave EM simulation.

4. Thermal Expansion Failure Problems:

CTE mismatch under power devices causes pad/copper cracking.

Thermal Expansion Failure Solution:

Use mesh copper under power components with via arrays to inner ground.
Select FR-4 TG170 for CTE compatibility.

5. Fine-Pitch Component Shorting Problems:

Copper near BGA/QFN pads causes solder bridging.

Solution:

Set copper clearance ≥0.2mm (8mil) in Altium DRC.
Remove local copper under BGAs while preserving critical signal paths.

Why Choose Best Technology as Copper Pour PCB Supplier?

19-Year PCB Manufacturing Expertise: Proven track record in handling complex designs (e.g., HDI, RF, automotive) with 98.5% on-time delivery.
Global Certifications: ISO 9001, ISO 13485, UL and RoHS compliance guarantee product safety and regulatory adherence.
Fast Turnaround: 24-hour rapid prototyping and 5-day standard delivery for copper pour PCBs (3oz-10oz), accelerating time-to-market.
Cost Efficiency: Optimized production processes and bulk material procurement reduce costs by 15-20% compared to industry averages.
Strict Quality Inspection: 100% AOI inspection for bulk orders + 3D X-Ray scanning ensures <0.05% defect rate, minimizing rework costs.
Free DFM Analysis: Pre-production design checks identify copper pour issues (e.g., dead zones, sharp angles), saving $5,000+ in potential redesign costs.
Free Engineering Support: Dedicated team provides copper pour optimization, impedance control, and thermal management solutions at no extra charge.

Welcome to contact us if you have any inquiry for copper pour PCB: sales@bestpcbs.com.

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Embedded Copper Coin PCB Supplier| Best Technology

Tuesday, August 19th, 2025

What is embedded copper coin PCB? Let’s explore its structure, benefits, applications, connector methods, design guide, production processes together.

Are you troubled with these problems?

Is your product throttled by poor heat dissipation?
Are traditional cooling solutions squeezing your design space?
Is your PCB frequently experiencing thermal failures under complex operating conditions?

Best Technology can offer services and solutions:

Customized thermal design: ANSYS simulation and field verification.
Flexible manufacturing services: 0.2-2.0mm copper coin options.
Full-process quality control: 16 critical process checks for reliability.

Welcome to contact us if you have any inquiry for embedded copper coin PCB: sales@bestpcbs.com.

What is Embedded Copper Coin PCB?

Embedded Copper Coin PCB (Embedded Copper Coin) is an innovative technology that improves heat dissipation by embedding copper sheets (called “copper coins”) within printed circuit boards (PCBs). These copper coins, typically in a circular or rectangular stepped design, efficiently absorb and dissipate heat generated by electronic components, making them particularly suitable for high-power devices or miniaturized products (such as 5G communications equipment and space electronics).

This technology leverages copper’s high thermal conductivity to mount heat-generating components directly on the copper coins, significantly overcoming the limitations of traditional PCB heat dissipation vias or metal substrates, achieving more compact and efficient heat dissipation.

Structure of Embedded Copper Coin PCB

1. Copper Coin Body

Material: ≥99.9% pure copper, 0.5–3mm thick, 5–20mm diameter, nickel-plated.
Design: Stepped profile expands heat contact; fits round/rectangular chips.

2. Embedding Process

Process: Laser/mechanical insertion into PCB layers, FR-4 bonded, resin-filled for flatness.
Tolerance: Adhesive residue ≤0.1mm to prevent via cracks.

3. Conductive Interconnects

Vias: Metallized, copper-plated ≥25µm for low impedance.
Clearance: ≥0.2mm between layers (3kV AC safe).

4. Insulation & Protection

Solder Mask: ≥15µm edge coverage.
Vias: Resin-filled to reduce thermal stress.

5. Thermal Management

Path: Thermal adhesive/aluminum substrate beneath coin for vertical cooling.
Stacked Design: Simulation-optimized heat flow.

Advantages of Copper Coin-Embedded PCB

Highly Efficient Heat Dissipation: Copper exhibits excellent thermal conductivity and is embedded directly beneath heat-generating components to quickly dissipate heat and prevent overheating damage (such as power ICs or automotive-grade chips).
Saves PCB Space: No additional heat sink or complex air cooling systems are required, making it suitable for compact designs (such as drones and portable devices).
Improves Long-Term Reliability: Copper and PCB materials have similar coefficients of thermal expansion, reducing the risk of solder joint cracking and extending product life.
Lowers Overall Cost: The process is simpler than embedded copper coins, reducing production steps and material waste.
Supports Custom Design: Round and rectangular copper coins can flexibly adapt to different component shapes (such as special-shaped chips) to optimize heat conduction paths.

Applications of Embedded Copper Coin PCB

High-Power LED Lighting Cooling
RF/Microwave Power Amplifiers
New Energy Vehicle Power Systems
Industrial Power Equipment
Aerospace Electronics Systems
Server Power Modules
Power Electronics Converters
High-density packaged device cooling
Automated test equipment (ATE)
Audio power amplifiers

How is the Copper Coin Connected to the PCB?

Metallized Via Direct Connection

Copper coins connect to PCB inner layers via laser-drilled microvias (aperture ≥0.3mm), with copper plating thickness ≥25µm on via walls, ensuring low-impedance conduction (<10mΩ).
Suitable for high-current applications (e.g., EV traction systems carrying ≥200A).

Stepped Laminated Structure

Adopts OKI’s stepped copper coin design, where copper coins are laminated with PCBs using resin-filled gaps. Contact diameter 7mm, heat dissipation expanded to 10mm.
Requires controlled lamination temperature (170–200℃) and pressure (200–400psi) to avoid resin voids and elevated thermal resistance.

Conductive Adhesive Bonding

Uses thermal conductive adhesive (e.g., 3M 8810, thermal conductivity ≥1.5W/mK) to fix copper coins in non-conductive areas.
Ideal for high-frequency signal modules (e.g., mmWave radar) to prevent electromagnetic interference from metal vias.

How to Design A Embedded Copper Coin PCB?

Below are embedded copper coin PCB design guide:

1. Material & Copper Coin Parameter Design

Material selection: Select ≥99.9% purity electrolytic copper (thermal conductivity: 401W/(m·K)), with thickness matched to chip power (e.g., 1.5mm for 10W chips, 2.5mm for 20W chips).
Surface treatment: Nickel-plated (≥5µm); gold plating (≥1µm) for extreme environments.
Shape optimization: Stepped design expands contact area by 30–50%; rectangular coins for linear-package devices.

2. Embedding Position Planning

Single-layer boards: Align copper coin center with high-power component (e.g., CPU/GPU) heat core (error ≤0.2mm).
Multi-layer boards: Vertically stagger coins (e.g., Layer 2 coins offset 5mm from Layer 1).
Safety clearance: Maintain ≥0.5mm gap between coin edges and high-speed signal lines; ≥2mm from PCB edges.

3. 3D Thermal Interface Design

Vertical Cooling:

Apply thermal adhesive (e.g., Arctik 8800, 3.0W/(m·K)) to fill micro-gaps between chip and coin.
Embed aluminum substrate (1.0mm thickness) beneath coins; connect to backside heatsinks via thermal vias.

Horizontal Cooling:

Array small coins (3mm diameter, 5mm pitch) under uniformly heated devices (e.g., FPGAs).
Deploy thermal via arrays (0.3mm diameter, 0.8mm pitch) around coins; fill with conductive epoxy (e.g., Ausbond 9105, 1.5W/(m·K)).

4. Thermal Via Optimization

Via parameters: Diameter ≥0.3mm, copper plating ≥25µm, depth ≤2/3 of PCB thickness.
Process enhancement: Electroless Nickel Immersion Gold (ENIG) finish for via walls; array vias in ring or matrix patterns (pitch ≤1mm).

5. Manufacturing Process Control

Embedding methods:

Small coins (≤5mm): Laser drilling (±0.05mm accuracy), vacuum-adhesive fixation.
Large coins (≥10mm): Mechanical pressing (50–80psi), alignment pins for hole matching.

Resin filling: Use low-CTE (≤40ppm/℃) epoxy to fill gaps; cure via baking (150℃, 2 hours).

6. Thermal Simulation & Validation

Simulation phase: Model steady/transient thermal distribution using Ansys Icepak (input material parameters, via layout, and chip power data).

Physical testing:

Thermal imaging: Ensure junction-to-coin ΔT ≤5℃ (e.g., coin ≤115℃ at chip 120℃).
Temperature cycling (-40℃~125℃, 1,000 cycles): Inspect for cracks/delamination at coin-PCB junctions.

7. Standards Compliance Testing

Compliance: CPCA 6042 (embedded copper PCBs), IPC-6012C (rigid PCBs).
Dielectric testing: Apply 3kV AC between adjacent coins/ground; no breakdown for 60 seconds.

How to Design A Embedded Copper Coin PCB?

What is the Process of Embedded Copper Coin PCB?

1. Substrate Preprocessing & Copper Coin Fabrication

Substrate Cutting: FR-4 substrate cut to working dimensions (tolerance ±0.1mm), with simultaneous milling of copper coin positioning slots (depth = coin thickness +0.05mm).
Copper Coin Machining: CNC-shaped electrolytic copper (C11000), surface nickel-plated (2–5μm) + chemical roughening (Ra 0.8–1.2μm).

2. Inner Layer Production & Coin Embedding

Inner Layer Imaging: After circuit etching, black oxidation treatment applied to copper coin zones (surface area increased ≥30%).
Coin Assembly: Vacuum nozzle with visual positioning system (accuracy ±25μm) presses coins into slots; edges coated with conductive epoxy (thermal conductivity ≥5W/mK).
Pre-Lamination Inspection: X-ray detection of coin positional deviation (standard ≤0.1mm).

3. Multi-Layer Lamination Control

Stack-Up Structure: 2 high-TG prepreg sheets (e.g., IT-180A) placed above/below copper coin layer; copper foil pre-laminated with thermal adhesive film.

Vacuum Hot Pressing Parameters:

Stage 1: 120℃ / 3MPa / vacuum ≤10Pa
Stage 2: 180℃ / 8MPa / dwell 60min
Stage 3: Cooling to <50℃ before pressure release

Post-Pressing Treatment: Laser trimming of resin overflow; plasma cleaning of coin zones.

4. Drilling & Metallization

Step Drilling:

φ0.3mm pilot holes (through coin center)
Enlarged to φ0.5mm (aspect ratio ≤12:1)
Back-drilling residue ≤0.15mm

High-Thermal Via Metallization:

Pulse copper plating (average thickness ≥30μm)
Via filling with silver paste (thermal conductivity >200W/mK) or nano-aluminum resin.

5. Outer Layer Circuitry & Thermal Enhancement

Laser LDI Imaging: Circuit width compensation +0.1mm at coin connection zones (to offset lamination deformation).
Selective Thick Copper Plating: 3oz (105μm) plating around coin zones; 1oz (35μm) retention at non-thermal zones.
Thermal Via Arrays: φ0.25mm vias (pitch 1.0mm) within 1mm of coin edges, filled with thermal paste.

6. Surface Finish & Testing

Coin-Specific Surface Treatment:

Electroless nickel-palladium-gold (ENIG: Ni 5μm/Pd 0.2μm/Au 0.05μm) .
Or OSP + localized silver plating for oxidation resistance.

Thermal Validation:

Infrared thermography (ΔT ≤12℃ under 10W input)
Thermal cycling (-55℃~125℃, 1,000 cycles; impedance change ≤3%)

7. Final Inspection & Packaging

Coin-Specific Testing: Ultrasonic scanning (detect delamination); Shear strength test (≥50N/mm²)
Packaging: Antistatic vacuum packaging (internal humidity ≤10%RH); silicone pads added to coin zones.

Why Choose Best Technology as Embedded Copper Coin PCB Supplier?

Reasons why choose us as embedded copper coin PCB supplier:

Certification Compliance‌: ISO 9001, IATF 16949, ISO 13485 and RoHS, UL certified, and ensures global market compliance and reliability.
Superior Material Quality: Use ≥99.9% electrolytic copper (C11000) with nickel/gold plating. Ensures superior thermal conductivity (≥401W/m·K) and long-term reliability.
Reliable Quality Control‌: Strict process control with AOI/SPI/X-Ray inspection ensures 99.5% assembly yield and minimal defects.
24 Hours Rapid Prototyping: Accelerates product launches and time-to-market.
Free DFM Optimization: Reduces design errors by 40% and avoids costly rework.
One-Stop Solution: Simplifies vendor management, cutting admin work by 60%.
Advanced Thermal Solution: Guarantees stability for high-power applications (e.g., automotive/5G).
24/7 Technical Support: Minimizes downtime and ensures smooth mass production.

Welcome to contact us if you have any request for embedded copper coin PCB: sales@bestpcbs.com.

Tags:Embedded Copper Coin PCB
Posted in best pcb, bestpcb, PCB Technology | No Comments »

Splitter PCB Design & Assembly, PCBA Service Supplier

Tuesday, August 19th, 2025

What is splitter PCB? Let’s explore its function, types, applications, technical parameter, design guide, assembly processes through this blog.

Customer Pain Points and Difficulties:

Severe signal attenuation and short transmission distance? (Splitter PCB uses high-precision impedance matching to ensure lossless signal distribution and extend transmission distance.)
Multi-path signal interference and poor stability? (Splitter PCB’s optimized isolation design effectively suppresses EMI/EMC and ensures signal purity.)
Complex assembly process and low yield? (Splitter PCB’s standardized production process and automated SMT placement improve consistency.)

Best Technology can provide services and solutions:

Customized Design Support: Provide impedance simulation and stack up optimization to ensure Splitter PCB meets your signal distribution needs.
Efficient Production and Delivery: 7-day proofing and 15-day mass production, quickly responding to your project schedule.
Full-Process Quality Assurance
ISO 9001 control throughout the entire process, from PCB manufacturing to assembly and testing, ensures reliability.

Let Best Technology be your splitter PCB expert and solve your signal distribution challenges! Contact us now if you have any request for splitter PCB design and assembly: sales@bestpcbs.com.

What is Splitter PCB?

A splitter PCB is a printed circuit board (PCB) specifically designed for signal or power distribution. It distributes input signals/currents to multiple output ports in equal or unequal proportions, enabling system signal synchronization or power isolation.

What is the Purpose of Splitter PCB?

RF Signal Distribution: Used in communications equipment (such as base stations and routers), it splits RF signals into multiple channels.
Mixed Signal Isolation: Isolates noise interference from analog and digital circuits.
Power Management: Distributes different voltage rails in multi-voltage systems (such as automotive BMS).
High-Speed Interface Optimization: Improves the transmission stability of high-speed signals such as PCIe/USB4.
Test Support: Facilitates device debugging and performance monitoring.
Flexible Electronics Integration: Adapts to the compact space requirements of wearable devices and foldable displays.

What Are Types of Splitter PCB?

POE Splitter PCB: Separates Power over Ethernet (PoE) into data and power, adapting to non-PoE devices.
Audio Splitter PCB: Distributes audio signals to multiple output channels (such as 3.5mm/RCA jacks), supporting parallel connection of speakers or headphones.
Fan Splitter PCB: Connects multiple fans (12/24V) in parallel, simplifying wiring for cooling systems (such as 3D printers or chassis fans).
HDMI Splitter PCB: Duplicates a single HDMI signal to multiple displays, supporting 4K/8K video transmission (such as conference presentations or advertising screens).
USB Splitter PCB: Expands a single USB port into multiple ports, supporting peripheral connection or charging (such as keyboards, mice, and mobile phones).

What Are Applications of PCB Splitter?

Communications and RF Systems – Signal distribution (such as 1-to-2 splitters), frequency band division (broadband equal power division), and RF test equipment (connecting signal sources and measuring instruments).
Audio Equipment – Speaker crossover (high/mid/low frequency band distribution), electronic crossovers (weak signal division before amplifiers).
Automotive Electronics – Power control (motor controllers, battery management systems), intelligent driving (millimeter-wave radar high-frequency PCBs), new energy battery data acquisition cables (FPC flexible monitoring).
Consumer Electronics – Smartphones/tablets (HDI boards, flexible PCBs), wearable devices (lightweight and heat-resistant designs).
Industrial and Aerospace – Extreme environments (high temperature/high pressure/strong electromagnetic interference), high-precision control (multilayer boards, ceramic substrates).
Data Centers and Cloud Computing – High-speed signal transmission (servers, data center multilayer boards), low-latency data processing.
Smart Home and IoT: Wireless device integration (sensors, communication modules), low-power flexible PCB design.

HDMI Splitter PCB Design Technical Parameter

Parameter Category	Technical Specifications
Input/Output Interface	1×HDMI input, 2×/4×/8×HDMI outputs (configurable)
HDMI Version Support	HDMI 2.0b/2.1 (supports 4K@60Hz, HDR, HDCP 2.2/2.3)
Resolution Support	Maximum 4K@60Hz (4:4:4), compatible with 1080P/720P and below
Signal Bandwidth	18Gbps (HDMI 2.0) / 48Gbps (HDMI 2.1)
Operating Voltage	DC 5V (typical)
Power Consumption	≤5W (static), ≤10W (dynamic)
PCB Layers	4-6 layer board (impedance-controlled layers)
PCB Material	FR-4 (Tg≥170℃), optional high-frequency material (e.g., Rogers 4350B)
Differential Impedance	100Ω±10% (HDMI differential signal lines)
Signal Integrity	Insertion loss ≤-3dB@6GHz, return loss ≤-10dB@6GHz
EDID Support	Dynamic/Static EDID storage (EEPROM capacity ≥256Byte)
HDCP Support	HDCP 1.4/2.2/2.3 compliant
Connector Type	HDMI Type A female socket (gold-plated contacts, thickness ≥15μm)
ESD Protection	Human Body Model ±8kV, Machine Model ±200V (IEC 61000-4-2)
Operating Temperature	0℃~70℃ (commercial grade), optional -40℃~85℃ (industrial grade)
Certification Standards	CE, FCC, RoHS, HDMI Adopter Certification

How to Design a HDMI Splitter PCB?

HDMI splitter PCB design guide:

1. Basic Layout and Stackup Design

Shortening the signal path:

Minimize the distance between the HDMI connector and the processing chip (such as the TMDS341A) to reduce signal attenuation and EMI.

Stackup Structure:

Use at least a 4-layer PCB (6 layers recommended), including a complete power and ground layer.
High-speed signal layers should be placed adjacent to the ground layer to enhance magnetic field coupling and suppress EMI.

2. Differential Signal Impedance Control (100Ω)

Trace Rules:

A 1:1 differential pair width/space ratio is recommended, with intra-pair error ≤ 5 mil and inter-pair error ≤ 10 mil.
Trace spacing (s) must meet the following requirements: s < h (dielectric thickness), s < W (line width), and d > 2s (distance from other traces).
Use a 2D field solver to accurately calculate impedance, avoiding reliance on empirical values.

Via Design:

Use small vias (8 mil/16 mil recommended) to reduce capacitance effects and impedance drop.
Avoid switching high-speed signals across different layers; otherwise, additional return vias will be required.

3. Power Supply and Decoupling Capacitor Design

Power Inlet: Place a 10μF tantalum capacitor for voltage regulation.
Chip Power Supply: Place a 0.1μF or 0.01μF ceramic capacitor next to each high-speed chip, and connect the capacitor pins with double vias to reduce inductance.
Decoupling Capacitors: Configure at least one 4.7μF capacitor and five 0.1μF capacitors, connecting them directly to the power plane (minimizing the path).
Power Plane: Avoid signal lines crossing split planes to ensure a continuous return path.

4. EDID Management Strategy

EDID Compose Mode: Automatically analyzes the resolutions of all displays and selects the lowest compatible value (e.g., 1080P) to ensure compatibility.
Fixed Mode: Forces the output to a specific resolution (e.g., 4K@60Hz) to accommodate high-end devices.
Priority Setting: Supports port priority (for example, when Output 1 is disconnected, Output 2 defaults to 1080P)

5. Design for Manufacturability (DFM)

Trace Equal Length:

Length deviation within a differential pair should be ≤ 5 mil to prevent EMI caused by phase shift.
Use curved or serpentine traces to correct for length differences.

Pad and Spacing:

HDMI pads should be minimized to prevent impedance mismatch.
The copper pad to board margin distance should be ≥ 75 mil to meet production process requirements.

6. Expandable Functionality and Compatibility

Output Port Planning:

Select the number of ports based on requirements (e.g., 1×2/1×4), and reserve one or two spare ports for upgrades.

Supported Protocols:

Ensure support for HDCP 1.4+/HDMI 2.0, 4K@60Hz, and 3D formats.
Integrate CEC commands (e.g., one-button standby and remote control passthrough) to enhance the user experience.

External Power Supply:

Multiple ports (≥4 outputs) require a separate 12V/5A power supply to avoid power shortages.

7. Design Considerations

Avoid Cross-Splits: A complete reference plane is required beneath the differential lines, otherwise impedance jumps and noise will occur.
Capacitor Selection: Use low-ESL ceramic capacitors for high-frequency ranges (>100MHz) and tantalum capacitors for voltage stabilization in low-frequency ranges.
Connector Quality: Use connectors that meet HDMI impedance standards to avoid signal reflections.

How to Assemble a Splitter PCB?

Below are splitter PCB assembly processes:

1. Prepare Materials & Tools

Gather Splitter PCB (pre-etched), component kit (resistors, capacitors, transmission lines), solder wire, flux, soldering iron, tweezers, multimeter.
Inspect PCB for cleanliness and shorts; verify components match BOM (e.g., resistor values).

2. Component Placement

Align components with PCB silkscreen:

Insert resistors/capacitors into pads; press gently.
Embed transmission lines (e.g., quarter-wavelength microstrip) into slots, ensuring contact with pads.
High-frequency parts (e.g., Wilkinson resistors) must follow polarity marks.

3. Soldering

Set iron to 280–320°C (use lower temp for PTFE to avoid warping).
Steps:
a. Apply flux to pad/lead.
b. Feed solder until melted; remove iron for smooth joints.
c. Use “drag soldering” for SMD parts.
Focus: Transmission line joints and isolation resistors (avoid cold joints/bridges).

4. Quality Inspection

Visual check: Conical, shiny solder joints with no cracks.
Electrical test: Measure resistance (e.g., isolation resistors) with multimeter (≤5% deviation).
Continuity test: Short input to one output; others should show no connection.

5. Functional Verification

Connect signal generator and spectrum analyzer:
a. Input signal to PCB; measure output power (e.g., 1-to-2 divider: ≤0.5dB difference).
b. Test port isolation (e.g., ≤-20dB).
Debug: Re-solder components if power imbalance or poor isolation persists.

6. Cleaning & Protection

Wipe flux residue with alcohol to prevent corrosion.
Apply conductive adhesive on edges for RF applications to reduce EMI.
Package in anti-static bags with specs/test results labeled.

7. Notes:

Use automated soldering for high-frequency PCBs (e.g., 77GHz automotive radar) to avoid parameter shifts.
Prioritize network analyzers for testing; multimeters suit low-frequency checks only.

Why Choose Best Technology as PCBA Service Supplier?

Reasons why choose us as splitter PCB assembly service supplier:

19 Years of Industry Experience: Proven expertise in RF/high-speed splitter PCB assembly for 5G, automotive, and IoT applications.
Full Certification Compliance: ISO 9001, IATF 16949, ISO 13485 and RoHS, UL certified, and ensures global market compliance and reliability.
Cost-Effective Solutions: Competitive pricing and optimized material sourcing help reduce your production costs by 15-30%.
Free DFM & Design Support: Expert impedance matching (e.g., 50Ω RF traces) and signal integrity analysis ensure optimal splitter PCB performance.
Reliable Quality Control: Strict process control with AOI/SPI/X-Ray inspection ensures 99.5% assembly yield and minimal defects.
Fast Turnkey Assembly: 7-day prototype delivery and 15-day mass production for splitter PCB orders (100pcs–10Kpcs).
Advanced SMT Capabilities: Supports 01005-size components and 0.3mm BGA assembly for high-density splitter PCB designs.
Effective Signal Isolation: Dedicated EMI/EMC control measures prevent crosstalk in mixed-signal splitter boards.
Flexible Scalability: Seamless transition from prototypes to large-scale production (1M+ units) with consistent quality.
24/7 Technical Support: Dedicated engineers provide real-time DFM feedback and troubleshooting support.

Welcome to contact us if you have any request for PCBA service: sales@bestpcbs.com.

Tags:PCB Splitter, Splitter PCB
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PCB Footprint Standards and How to Make Footprint PCB?

Tuesday, August 19th, 2025

A footprint PCB is especially significant in component placement accuracy, soldering reliability, electrical performance, thermal management, and inspection and testing. This blog explains the meaning, standards, design guidelines, creation process, and precision methods of footprint PCBs to help engineers achieve accurate, reliable, and manufacturable circuit board layouts.

Do you have these problems on PCB prototype or mass production projects?

Manufacturing and assembly problems due to the non-standardized design?
Lacking the knowledge about the standardized design rules?
Absence of understanding of the component footprints?
Deficiency applies to the PCB footprint library?

Below are the workable solutions provided by Best Technology.

Fully follow and apply the standardized design norms to improve the PCB yield.
Employ a PCB footprint library to improve the design efficiency and reduce the rate of design mistakes.
Boost the design verification and inspection to improve the design quality and reduce the design failure.

Best Technology is a major PCB and SMT assembly factory, fully compatible with ISO 9001, ISO 13485, IATF 16949, AS9100D, UL, REACH, and RoHS standards. Most of our engineers have worked in Best Technology for over 10 years, gaining a sufficient understanding of what PCB footprints are, the relevant standards, design rules, creation steps, and accuracy techniques. If you have further questions, pls contact us directly at +86-755-2909-1601 or sales@bestpcbs.com.

PCB Footprint Standards and How to Make Footprint PCB?

What is footprint PCB meaning?

Put simply, a footprint PCB is a visual map on the board that indicates exactly where each component will sit. It clearly marks the positions, including pads, holds, and outlines of the components. The problems of misalignment or the soldering issues will occur even if it is just minor inaccuracies. Therefore, Best Technology provides the prototyping, which undergoes strict checking and validation service, that will benefit from smooth manufacturing and cost efficiency.

What are footprint dimensions meaning?

Footprint dimensions define the size and spacing of the pads, pins, and holds. This includes the length, width, pad diameter, and the spacing of the pins. The correct size can prevent solder bridging, improve the mechanical stability, and provide automation assembly convenience. For example, if the capacitor’s pad size is wrong, that will cause movement during the soldering and will lead to failures later. Best Technology will double-check the size according to the data sheet, to ensure the correctness the first time.

What are the PCB footprint standards?

Standards guide how to lay out the footprints. For example, IPC-7351 makes a guideline of the pad size and the tolerance; however, JEDEC provides the semiconductor footprints guidelines. If we are fully compatible with standards, the smooth assembly and quality checking can be assured. However, if we ignore the standards, the time and the money may be wasted. Best Technology follows standards to do PCB footprint efficiently, avoiding rework and delay.

What are some PCB footprint generator tools?

There are various tools that help engineers to generate and verify PCB footprints. Popular options include KiCad, Altium Designer, Eagle, and EasyEDA. These tools feature prebuilt libraries, customization, and compliance checks. Using the tools correctly can reduce human error and expedite the design process. Best Technology provides guidance about the library management and PCB footprint verification, which makes the workflow more reliable.

What does a Footprint PCB design do?

A footprint PCB design ensures every component is assembled to the circuit board, compatible with the electrical connection, mechanical match, and manufacturability. Making the PCB footprint precisely can reduce the soldering problem and the assembly failure. We can take it as the bridge between the schematic and the actual circuit boards. Best Technology double checks about every PCB footprint and the circuit board layout, aiming to get the smooth integration and reduce the rework.

PCB footprint design guidelines

Following design guidelines improves both reliability and manufacturability. The key recommendation includes:

First, fully compatible with IPC-7351 or JEDEC standards.

Then, make use of the data sheet to verify pad size and spacing.

Next, ensure the solder mask clearance to prevent bridging.

And keep the consistency between the component direction and the pin number.

Finally, make a record of the footprint information for reference in the near future.

Best technology provides the DFM analysis, customization checking, and technical consultation, which makes your order proceed more effectively, avoiding the common mistakes and ensuring the direct manufacture of the boards.

How to make a pcb footprint creation?

Here is how to make a PCB footprint creation for your review.

First, make a confirmation about the component types and refer to the data sheet.

Next, confirm the pad size, pin spacing, and outline dimensions.

Then, employ the footprint generator or PCB software to draw the footprint.

And double-check all the dimensions according to the standards and data sheet.

Finally, checking the component placement to ensure precision.

There are common to get troubles for the engineers, which lead to the board waste and the manufacturing delay. Best Technology is a leading PCB manufacturer in China, providing professional guidance, design optimization, and verification services to save time and prevent mistakes.

How to ensure the high precision pcb footprint sizes?

It is helpful to know that the high-precision PCB footprint prevents assembly problems effectively. Here are the practical ways, for reference.

Carefully checking the tolerance in the datasheet.

Apply the verified library or template.

Keep consistency of the unit, such as mm, mil.

Final review it before publishing the design.

Best Technology provides rigorous verification and the existing template, reducing human errors, expediting manufacturing, and finally ensuring high-quality PCBs.

Case about Footprint PCB in Best Technology

There are some of our customers who require a high-precision PCB footprint for prototype and small batch manufacturing. Best Technology helps customers to make a high-precision footprint and perform a DFM analysis to ensure full compatibility with the industry standards. Here are some photos for your review.

In a nutshell, footprint PCB is especially critical to the precise, efficient, and reliable manufacturing. Getting some knowledge about the dimensions, standards, and design guidance can prevent costly mistakes and improve manufacturing efficiency. Using the tools and the verification methods correctly ensures high-quality results.

Best Technology has been in the PCB industry for over 19 years, providing support and service throughout every stage for customers, from footprint PCB creation to verification, DFM analysis, prototype, mass production, and SMT assembly. We grasp the key pain points and have the specific solutions to tackle them, such as component misalignment or non-compliant pads. If you have any PCB or PCBA inquiry, pls don’t hesitate to find us for help via sales@bestpcbs.com. We are fully committed to giving our engagement and expediting the market entry time of your products.

Tags:footprint pcb
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What is Copper Busbar? PCB Copper Busbar Manufacturers

Tuesday, August 19th, 2025

Are you worried about these issues?

Is copper busbar overheating in high-current applications, causing efficiency drops or even system shutdowns?
Is corrosion or oxidation in humid or harsh environments leading to frequent maintenance?
Do you need flexible copper busbar customization to fit different battery modules or inverter layouts?

Best Technology provides tailored copper busbar solutions that balance cost, performance, and flexibility. We offer:

Competitive pricing directly from manufacturer
Customized sizes, coatings, and shapes
High durability = long-term cost savings
No minimum order quantity requirements, I pcs prototype order is available

If you are comparing copper busbar manufacturers or exploring advanced copper busbar PCB designs, Best Technology can help. With certifications including ISO9001, ISO13485, IATF16949, and AS9100D, we maintain strict quality control from raw material to finished product. Our MES system keeps every component traceable, while competitive copper busbar price and flexible engineering support bring added value.

Whether you need standard copper busbar, custom busbar copper shapes, or integrated PCB busbar solutions, Best Technology offers expertise and reliability in every project. If you are interested in copper busbar or copper busbar pcb, welcome to contact us at sales@bestpcbs.com.

What is Copper Busbar?

A copper busbar is a flat strip, rod, or bar of copper designed to conduct electricity. Unlike flexible wires, it’s rigid, strong, and tailored to carry heavy current loads. You’ll often find it inside switchgear cabinets, power distribution panels, and large battery packs.

Why copper? Because copper has excellent conductivity and thermal performance. It carries more current per square millimeter than most other metals while staying stable over long service periods. For engineers, this means reduced energy losses and fewer overheating issues.

In short, copper busbar is the highway for electricity inside modern systems.

What is Copper Busbar?

Why is it Called a Busbar?

The word “bus” in electrical engineering describes something that collects and distributes. Just as a city bus gathers passengers and delivers them to different stops, a busbar gathers current from various circuits and spreads it across the system.

The “bar” part is literal—it’s a bar of conductive material. Together, the term “busbar” reflects its function and shape. Over decades, this word became standard, and now it’s used across industries worldwide.

How to Make a Copper Busbar?

The process of making busbar copper combines precision with material science. Here’s how manufacturers typically approach it:

1. Copper Selection – Most copper busbar manufacturers choose high-conductivity grades such as ETP (Electrolytic Tough Pitch) or OFHC (Oxygen-Free High Conductivity). These ensure stable performance.

2. Cutting and Shaping – Large copper sheets are cut into required sizes. CNC punches and hydraulic presses shape the bar with consistent accuracy.

3. Drilling and Punching – Holes and slots are added for bolted connections. This step requires exact tolerances so that joints stay secure.

4. Bending – Depending on installation needs, busbars are bent into L, U, or Z shapes without compromising mechanical strength.

5. Surface Finishing – To prevent oxidation, surfaces may be tin-plated, silver-plated, or coated with nickel. This not only protects but also improves contact reliability.

6. Insulation (Optional) – In compact systems, epoxy coatings or heat-shrink sleeves are added to prevent accidental shorts.

Every step is controlled to deliver high current capacity while keeping mechanical stability intact.

How to Clean Copper Busbar?

Over time, copper busbar surfaces can tarnish. A thin oxide layer forms, which slightly increases resistance. Cleaning restores performance. Here are some practical methods:

Mechanical cleaning – Sandpaper, wire brushes, or abrasive pads can remove the oxidation layer.
Chemical cleaning – Mild acidic solutions like vinegar mixed with salt, or commercial copper cleaners, dissolve corrosion without damaging the base metal.
Protective treatment – After cleaning, applying a thin coat of petroleum jelly or anti-oxidation grease helps slow down further tarnish.

Routine cleaning is important in high-current systems, as even small resistance increases can generate heat under load.

How to Calculate Copper Busbar Size?

Choosing the right copper busbar size means balancing current capacity with safety. Engineers often use a current density rule to determine cross-sectional area.

The common design range is 1.2 to 1.6 A per square millimeter of copper in open air.

Formula:

For example, a busbar that needs to carry 800A at 1.5 A/mm² should have at least:

If designed as 40 mm wide and 14 mm thick, this cross-section provides adequate capacity. Designers then check thermal rise and cooling conditions to finalize the dimension.

Copper Busbar vs Copper Busbar PCB

Although both serve as conductors, there are differences between traditional copper busbar and copper busbar PCB:

Copper Busbar – A standalone strip or bar. Common in switchgear, transformers, and large distribution panels.
Copper Busbar PCB – A printed circuit board reinforced with very thick copper layers or embedded copper strips. Used in compact high-power electronics such as EV inverters.

The advantage of copper busbar PCB is space efficiency. Instead of bulky bars and cables, the PCB integrates power and signal layers together, simplifying assembly.

Busbar Copper PCB

Why Choose Copper Busbar PCB?

Copper busbar PCB, sometimes called embedded busbar PCB or busbar-integrated PCB, is a smart evolution of traditional busbars. In some industries, it is also referred to as reinforced thick copper PCB, since the board integrates additional copper bars or strips inside or on the surface to handle heavy current.

The reason many designers choose copper busbar PCB over standalone busbars lies in its unique advantages:

Compact design – Instead of bulky copper bars and multiple cables, busbar copper is embedded in the PCB, reducing space requirements.
Improved thermal balance – Heat spreads evenly across the board, preventing local hotspots in high-power circuits.
Simplified assembly – Fewer mechanical joints mean lower installation time and reduced risk of loose connections.
Cost efficiency – By combining signal and power layers in one PCB, manufacturers save both material and labor cost.
Reliability – With laminated structure and less mechanical stress, copper busbar PCB performs well even in vibration-heavy environments such as automotive or industrial drives.

Copper Busbar Size and Current Rating Table

Here’s a general table showing copper busbar size with approximate current ratings (open air, 35°C rise). Values vary depending on installation and cooling.

Thickness (mm)	Width (mm)	Max Current (A)	Typical Applications
1	10	50	Small electronics
2	20	150	Industrial control
3	25	250	Switchboards
5	50	500	EV battery modules
10	100	1200	Power distribution systems

These values are approximate. Always confirm with copper busbar manufacturers for precise specifications based on your operating environment.

How Much Does a Copper Busbar of Length 40 cm Carry?

The capacity depends mainly on cross-section, not just length.

A 20 × 5 mm busbar of 40 cm can carry about 160–200A.
A 40 × 10 mm busbar of the same length can handle up to 700A.

Length matters for voltage drop, but current capacity is almost entirely governed by cross-section and cooling.

Why Copper Busbar is Suitable for Electric Vehicles?

Electric vehicles place extreme demands on conductors. High current during acceleration, fast charging, and compact layouts require components that can cope with stress. Copper busbar delivers in several ways:

Efficient conduction – Copper reduces resistive loss, extending driving range.
Thermal control – With high conductivity, copper disperses heat effectively during charging cycles.
Space saving – Laminated copper busbars replace bundles of cables, reducing weight and assembly time.
Durability – Resistant to vibration and mechanical wear, critical for vehicles exposed to constant motion.

That’s why most EV battery packs and controllers today rely heavily on laminated busbar copper.

What is a Copper Busbar PCB Used For?

Power electronics – Converters, inverters, and rectifiers.
Automotive – EV drive systems, on-board chargers, and battery management units.
Renewable energy – Solar string inverters and wind turbine controllers.
Industrial systems – Robotics, automation drives, and motor controllers.

FAQs

Q1: What makes copper busbar better than aluminum busbar?

Copper has higher conductivity and better mechanical durability, leading to improved performance and longer service life.

Q2: Can copper busbar be customized?

Yes. Width, thickness, plating, and hole punching can all be tailored to specific installations.

Q3: What is the Copper Busbar HS Code?

Most copper busbars fall under HS Code 7407, covering copper bars and profiles.

Q4: What drives copper busbar price?

Mainly copper market fluctuations, plus cost of processing and plating.

Q5: Is copper busbar PCB the same as heavy copper PCB?

It is a type of heavy copper PCB, but they have several differences. Heavy copper PCB only increases copper layer thickness, while copper busbar PCB embeds solid busbars for even higher current handling.

This is the end of this blog, if you have any other questions about copper busbar pcb, you are welcome to contact our team, our sales are always online!

Tags:Copper busbar HS code, copper busbar manufacturers, copper busbar size and current rating, copper busbar pcb
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Copper Balance PCB, Copper Balancing in PCB

Tuesday, August 19th, 2025

What is copper balance PCB? Let’s explore its technical parameter, purpose, application, design guide and plating uniformity optimization solutions.

Are you troubled with these problems?

How can we ensure signal stability with uneven copper holes? (copper balance PCB heat dissipation and balanced plating)
How can we prevent poor soldering due to interlayer deviation? (copper balance PCB rigidity and deformation prevention)
How can we accurately control high-frequency impedance fluctuations? (copper balance PCB temperature drift suppression)

Best Technology can provide solutions:

Customized electroplating parameters improve copper hole uniformity by +40%
3D simulation predicts interlayer deviation risks
Dynamic compensation technology achieves impedance tolerance of ±5%

Welcome to contact us if you have any request for copper balance PCB: sales@bestpcbs.com.

What is Copper Balance PCB?

A copper balance PCB( also called copper balancing in PCB) requires symmetrical distribution of copper traces and coverage within each layer of the PCB stackup, ensuring consistent copper weight and thickness on the top and bottom layers (or within each inner layer). This is similar to a mirror image design, where the top and bottom layers are perfectly symmetrical to prevent mechanical stress caused by differences in thermal expansion coefficients. For example, during the CAD design phase, engineers create new layers (such as Layer 0 for the board outline and Layer 1 for top-side copper traces) and calculate copper areas to ensure even coverage on both sides.

Copper Balance PCB Technical Parameters

Technical Parameter	Specifications
Copper Thickness Range	Inner Layers: 0.5-3oz (17-105μm)
Copper Thickness Range	Outer Layers: 1-4oz (35-140μm)
Symmetry Tolerance	Layer-to-Layer Copper Distribution Deviation ≤5%
Fill Pattern	Low-Density Areas: Solid Blocks (≥5mm²)
Fill Pattern	High-Density Areas: Mesh Grids (0.3-0.8mm Pitch)
Current Density	Inner Layers: 1.2-1.8A/ft²
Current Density	Outer Layers: 0.8-1.2A/ft² (With Thieving Dots)
Minimum Feature Size	Isolated Copper Dots: Diameter ≥50μm
Minimum Feature Size	Mesh Lines: Width/Spacing ≥80μm
Thermal Stress Resistance	After 3× Thermal Cycles (-40°C~125°C), Warpage ≤0.5%
Impedance Control Differential Pair	±5Ω Tolerance
Single-Ended Trace	±8% Tolerance
DFM Validation Methods	3D Field Solver for Copper Distribution Analysis; IPC-2221A Current Density Check

Purpose of PCB Balancing Copper

Preventing PCB board twisting, bending, or warping: Symmetrical copper trace distribution reduces mechanical deformation caused by differences in thermal expansion coefficients, ensuring a flat board and avoiding manufacturing defects and assembly issues.
Reducing ground impedance and voltage drop: Balanced copper coverage reduces ground resistance and stabilizes current flow, thereby reducing noise interference and improving power efficiency.
Reducing the risk of internal track fracture: Even copper distribution helps dissipate heat and stress, preventing damage to internal tracks caused by thermal stress or mechanical pressure.
Optimizing signal transmission and reducing interference: Copper foil filler improves interference immunity, improves signal integrity, and reduces high-frequency signal coupling and noise.
Enhancing thermal management: Copper acts as a heat dissipation layer, effectively conducting heat, eliminating the need for additional heat sink components, reducing manufacturing costs and the risk of thermal stress.
Increasing structural strength and reliability: Balanced copper increases the thickness of conductors and pads, ensuring strong connections between layers and improving the mechanical durability of the board.

Applications of Copper Balance PCB

LED street lights and traffic lights
Automotive lighting (headlights/taillights)
Surgical shadowless lamps and camping lights
Engine power controllers
Electric vehicle chargers and inverters
Servo motor drive circuits
Arc welder power modules
Solar inverters and UPSs
Textile machinery driver boards
CT/X-ray scanner heat sinks
Surgical lighting systems
5G base station filters
Server power modules
Airborne radar modules
Hi-fi audio amplifiers
Smartphone motherboards

Difference between Copper Balance vs Copper Thieving in PCB

Dimension	Copper Balancing	Copper Thieving
‌Core Objectives‌	Prevent physical deformation (warping, twisting)	Ensure plating uniformity (copper thickness, impedance consistency)
Application Layer‌	Inner layers only	Outer layers only
Added Elements‌	Non-conductive copper blocks (large-area fill)	Isolated copper geometries (dots, squares, etc.)
‌Key Risks‌	Lamination voids, thermal stress fractures	Over-etching (mushroom pads), impedance abrupt changes
‌Design Constraints‌ Requires	interlayer symmetric distribution	Must keep away from signal lines & impedance control areas

How to Achieve Copper Balancing in PCB?‌

Here are ways about how to achieve copper balancing in PCB:

1. Core Principles of Copper Balancing‌

Ensure symmetric copper distribution across PCB layers to prevent warping (max deviation <0.7% thickness)‌.
Maintain impedance consistency (±5% tolerance for high-frequency designs)‌.

2. Implementation Methods‌

Mirror Stack Design‌

Symmetrical copper coverage (top/bottom layers deviation <5%)‌.
Central layers (e.g., L3/L4 in 6-layer boards) should have thicker copper to distribute stress evenly‌.

Dynamic Plating Control‌

Pulse plating adjusts via copper thickness (40% uniformity improvement for blind vias)‌.
Monitor plating solution (60–80g/L Cu²⁺, 50℃±1℃)‌.

Copper Pour Optimization‌

Use grid copper (spacing λ/20) in non-routing areas to avoid resin flow issues‌.
Avoid sharp corners (radial edges minimize EMI)‌.

3. Quality Validation‌

Mechanical Test‌: Post-reflow warpage ≤0.3mm/m (288℃, 3 cycles)‌.
Electrical Test‌: 10GHz impedance variation ≤±2Ω‌.
Microscopic Analysis‌: Uniform copper grain size (≤5μm via SEM)‌.

4. Case Studies‌

HDI Board‌: BGA cracking due to 18% copper imbalance fixed by prepreg compensation (reduced to 3%)‌.
Aluminum Base PCB‌: Overheating resolved via stepped copper design (3oz in high-heat zones)‌.

5. Special Considerations‌

Thick Copper Boards (≥3oz)‌: Staged lamination (120℃/50PSI → 180℃/250PSI)‌.
Flexible PCBs‌: Low-temperature bonding (160–200℃) with flexible adhesives‌.

How to Achieve Copper Balancing in PCB?‌

Copper Balance PCB Design Guideline

1. Copper Thickness Selection

A 1oz (35μm) base copper thickness is preferred for standard boards. Power layers and high-current paths can be partially thickened to 2oz.
Multilayer boards require interlayer copper balance: the difference in copper foil area between adjacent layers should be ≤10% to prevent warping caused by thermal lamination.

2. Copper Foil Distribution Principle

Ground and power layers should use solid copper fill (Solid Pour) to reduce impedance and improve heat dissipation.
Signal layers should use grid copper fill (Grid Pour) to balance interlayer compressive stress.

3. Tracking Rules

Bend traces at 45° angles; avoid 90° right angles (to reduce reflections and space waste).
Critical signal trace widths should be ≥0.2mm. Power trace widths should be calculated based on current (Tool: PCB Trace-Width Calculator).
A 10% margin should be reserved for high-frequency signals to compensate for etching tolerances.

4. Via and Copper Connections

Annular rings on through-hole pads should be ≥0.15mm. Microvias should be ≥0.05mm.
Avoid unnecessary vias and prioritize blind and buried vias to optimize high-density routing.

5. Symmetrical Lamination Design

PCBs with four or more layers should use a symmetrical stackup (e.g., Top-GND-PWR-Bottom). The core board thickness tolerance should be ±10%.
The thicknesses of the copper and dielectric layers must match the coefficient of thermal expansion (CTE) to avoid delamination.

6. Heatsink Copper Area Treatment

Independent copper heatsinks should be provided beneath high-power devices to connect multiple vias to the internal ground plane.
Coordinate the opening ratios of the copper foil and solder mask to avoid localized overheating.

7. Design Checklist

Use Design for Manufacturing (DFM) tools to verify copper balance: inter-layer copper area ratio, minimum trace spacing, and aperture ratio.
Perform electrical rule checking (ERC) and design rule checking (DRC) before submitting process files.

8. Vendor Collaboration Requirements

Confirm the PCB manufacturer’s process capabilities (e.g., minimum trace width/maximum copper thickness) in advance.
Indicate special requirements (e.g., impedance control layer, ±10% copper thickness tolerance).

9. Design Document Annotation

Reference identifiers (R1/C2) should be placed away from densely populated areas to avoid obstruction.
Net names should be named according to their function (e.g., VCC_3V3, GND_DIGITAL).
Add a laminate diagram and indicate the copper thickness of each layer.

Copper Balance PCB Plating Uniformity Optimization Solution

‌Current Density Control‌

Forward pulse (100–200ms, 40–60A/dm²) + reverse pulse (5–10ms, 6–10A/dm²) reduces via-to-surface thickness ratio from 1:2.5 to 1:1.2, improving yield to 98.5%.
Adjust edge current density by 15–20% to minimize “edge effect” (edge plating thickness ≤ 1.8× center).

‌Plating Solution Improvement‌

Accelerator (4-amino-2-thiophene carboxylic acid, 40–60ppm) increases via-bottom deposition rate by 35%.
Leveler (heterocyclic quaternary ammonium salts, 20–30ppm) reduces surface copper growth by 50%.
Copper sulfate (60±5g/L), sulfuric acid (100±10g/L), temperature (50±1℃) reduces roughness (Ra) by 50%.

‌Equipment & Fixture Optimization‌

Optimize titanium basket positioning: Adjust bottom screen by 2mm reduces bottom thickness variation by 4%; adjust side screen by 20mm reduces CoV from 7.0% to 5.1%.
Use conformal anodes for complex boards, improving current distribution uniformity by 25%.

‌Spray System Calibration‌

Pressure gradient: 15–20% lower at edges reduces thickness variation by 35%.
Intermittent spray eliminates “bath effect,” improving uniformity by 40%.

‌Pre-Treatment & Process Control‌

Micro-etching (Ra 0.8μm) improves adhesion from 0.8N/cm to 1.5N/cm.
Strict degreasing (<0.5mg/cm² residue) reduces plating defects by 35%.

‌Real-Time Monitoring‌

Online bath composition control: Metal ion variation ±3%, additives ±5%.
Temperature control (50±0.5℃) improves uniformity by 15%.

‌Design Optimization‌

Copper distribution error ≤5% (≤8% for inner layers), reducing warpage by 30%.
Avoid isolated copper areas (<0.5mm²; fill or remove if necessary).

‌High-Density Zone Compensation‌

Differential pairs: +10% current reserve reduces impedance variation from ±15% to ±3%.
Laser vias (0.1mm) with pulse control: Height variation <0.2μm.

‌Quality Verification Standards‌

CoV (Coefficient of Variation): ≤10% (optimized to 5.1%).
Range method: ≥90% (requires high-end chemicals & rectifiers).

‌Reliability Testing‌

Thermal cycling (−55℃ to 125℃, 1000 cycles): No delamination; thick copper (≥3oz) improves bend strength by 150%.
Peel strength: Electrolytic copper ≥1.5N/mm, rolled copper ≥2.0N/mm.

Conclusion

To sum up, the above content is all about technical parameter, purpose, application, design guide and plating uniformity optimization solutions for copper balance PCB. If you have any other issues about copper balance PCB, please feel free to contact us: sales@bestpcbs.com. Looking forward to hearing from you soon!

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