2oz Thicker Copper Rigid-Flex PCB Manufacturing & Challenges

December 31st, 2025

Recently, Best Technology faced a huge challenge in a 2oz copper rigid flex PCB manufacturing, this board appeared simple on the drawing but revealed multiple layers of engineering challenges once entering mass production. But finally, we finished this project very well and overcome this challenge, let’s see what are the challenges on this project and how does our team overcome them!

Project Introduction

The board used a 70/25 double-sided adhesive ED flexible substrate with PI25/AD50 coverlay, coupled with a 2+2 layers dual access structure that required thick copper, small annular rings, narrow spacings, and FR4 stiffeners with extremely limited clearance. Each of these parameters independently creates difficulty, but combined, they demand precise collaboration between engineering, fabrication, and process control.

This article explains:

Why the design was inherently difficult
What manufacturing risks were present
How our engineering team solved each challenge
What PCB designers should avoid in similar projects
Why Best Technology can manufacture such high-reliability rigid-flex PCBs

Material Structure and Key Design Parameters

The board consisted of the following:

Flexible substrate: 70/25 double-sided adhesive ED copper
Coverlay: PI 25 µm + Adhesive 50 µm
Base copper: 2 oz copper
Layer count: Four-layer rigid-flex structure
Critical routing: 0.15 mm minimum trace/space
Plated hole: 0.66 mm with hole spacing of only 0.60 mm
Annular ring: 0.05 mm on certain pads
Stiffener: FR4 stiffener with 0.95 mm stiffener hole and 0.31 mm ribs

Material Structure and Key Design Parameters

This combination is common in advanced HDI rigid-flex PCB manufacturing, yet its manufacturability depends heavily on copper behavior, adhesive flow, and drilling tolerances.

Why This Rigid-Flex PCB Was Inherently Difficult?

1. Thick copper increases side-etching risk

With 2 oz copper, the etching rate is higher and lateral etch—often called side-etch—is harder to control. In this case, the side-etching amount reached: 0.0070 ± 0.003 mm. For ultra-fine traces in a rigid-flex PCB design, this will eat into the design margin.

2. Small annular rings compromise via reliability

Pads with 0.05 mm annular ring severely restrict drilling tolerance. In flex-rigid PCB fabrication, annular rings below 0.10 mm are classified as high-risk features.

Why This Rigid-Flex PCB Was Inherently Difficult?

3. Extremely tight stiffener clearance

The stiffener needed:

±0.20 mm placement tolerance
±0.05 mm drilling tolerance

But the designer only left 0.15 mm clearance, causing a mismatch between rigid-flex PCB stiffener alignment tolerance and actual manufacturing capability.

4. Thin FR4 stiffener ribs cause glue overflow

Ribs only 0.31 mm wide cannot allow adhesive to retreat during bonding, causing pure glue to overflow and block the stiffener holes.

Technical Challenge #1: Thick Copper Etching with Narrow Spacing

A 2 oz thick copper PCB combined with:

0.15 mm trace/space
0.05 mm annular ring
0.66 mm PTH

creates a situation where compensation is unavoidable.

However, after compensation (~0.007 mm), the remaining trace width would drop to:

0.08 mm (0.15 – 0.07 mm)

This is below the safe manufacturability range of most rigid-flex PCB suppliers.

Best Technology’s solution

Eliminated compensation on 0.15 mm traces
Implemented fine-tuned etching control
Maintained ~0.10 mm final copper width
Ensured full electrical reliability

This is a proven strategy in advanced rigid-flex PCB manufacturing for thick-copper builds.

Technical Challenge #2: Annular Ring Integrity in Plated Through Holes

Annular rings <0.10 mm are extremely vulnerable to:

Drill wander
Etching undershoot
Copper thinning

This is especially critical in high-reliability rigid-flex PCBs, where via integrity is essential.

Best Technology’s solution

Applied rigid-board-level PTH plating process
Improved copper thickness inside the via barrel
Adjusted drilling control to 0.65 ± 0.075 mm
Customer accepted partial ring breakage as long as electrical integrity remained intact

This ensured consistent via performance even in ultra-dense rigid-flex PCB layouts.

Technical Challenge #3: Stiffener Bonding, Alignment, and Adhesive Overflow

1. Why stiffener tolerance was problematic

In rigid-flex PCB assembly, stiffeners are critical for mechanical reinforcement. However:

Hole spacing was only 0.60 mm
Stiffener clearance only 0.15 mm per side
Combined tolerance ±0.25 mm

This inevitably leads to the stiffener covering the pads unless advanced alignment controls are used.

2. Why glue overflow occurs

Thin ribs (0.31 mm) cannot provide an escape path for adhesive. During lamination:

The glue squeezes into the holes
Holes become blocked
Boards fail inspection

3. Best Technology’s engineered solution

Pre-laminated pure adhesive onto FR4 stiffener
Re-drilled stiffener holes after bonding
Greatly reduced glue overflow
Added 100% AOI + manual inspection for hole clearing
Rejected defective boards, shipped only fully passing units

This is a common best practice in flex PCB stiffener processing when tolerances are tight.

DFM Guidelines for Rigid-Flex PCB Designers

Avoid annular rings under 0.15 mm, especially in 2 oz copper flex-rigid PCB design.
Avoid combining thick copper with fine lines, this will increase manufacturing risk.
Ensure stiffener clearance > total tolerance stack-up. If your clearance is smaller than the alignment tolerance, the stiffener will inevitably shift.
Keep stiffener ribs ≥0.5 mm
Send your design for DFM review before finalizing. A good rigid-flex PCB manufacturer will help adjust the stack-up, drill size, and stiffener layout to avoid expensive redesigns.

This case demonstrates how a complex rigid-flex PCB—with 2 oz copper, ultra-fine traces, small annular rings, and extreme stiffener constraints—can be successfully manufactured through detailed engineering, advanced process control, and disciplined quality screening.

Best Technology combines strong fabrication capability with practical DFM insight, enabling customers to produce compact, reliable, and manufacturable rigid-flex PCB designs that perform consistently under demanding conditions.

If you need support with your next rigid-flex or flex PCB project, our engineering team is ready to assist with stack-up review, DFM checks, or trial builds.

Tags: rigid flex pcb, Rigid Flex PCB Assembly, rigid flex pcb design, rigid flex pcb manufacturer, rigid flex pcb manufacturing
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Reliable Medical Flex PCB Assembly Solutions

December 23rd, 2025

Flex PCB assembly represents a revolutionary approach to electronic circuitry that enables bending and folding to fit compact medical devices. This technology transforms how we design everything from implantable pacemakers to advanced imaging systems by replacing rigid boards and bulky wiring with flexible, reliable alternatives. This guide explores the complete landscape of medical flex PCB assembly, from fundamental concepts to specialized manufacturing considerations for life-critical applications.

Why do medical device manufacturers struggle with implementing reliable flex PCB solutions?

Key Pain Points:

Ensuring reliability in life-critical medical applications where failure is not an option
Achieving miniaturization for implantable and wearable devices without sacrificing performance
Navigating complex medical regulatory requirements and certification processes
Managing higher initial costs while maintaining uncompromised quality
Preventing failures in dynamic flexing applications through proper design

Targeted Solutions:

Implement rigorous testing protocols aligned with medical standards (IPC-6013, ISO 13485)
Utilize advanced materials like polyimide and adhesiveless laminates for compact, reliable designs
Partner with manufacturers experienced in medical certifications and documentation
Optimize designs for manufacturability to control costs without compromising quality
Apply design guidelines specifically for dynamic vs. static flexing applications

At BEST Technology, we specialize in addressing these challenges through nearly 2 decades of experience in medical flex PCB manufacturing. Our expertise ensures that your medical devices meet the highest reliability standards while navigating the complex landscape of medical electronics. We hold ISO 13485 certification, which governs our quality management system for medical device production. This means our processes—from design, FPC prototyping, and sourcing to manufacturing, assembly, and testing—are meticulously controlled to ensure the safety and reliability of medical PCBs.

And it is worth mentioning that we have implemented an MES to digitally transform our shop floor, enabling full traceability and data-driven decision-making. Pls feel free to contact our team at sales@bestpcbs.com to discuss your specific medical flex PCB or medical PCB assembly requirements.

What Is Flex PCB Assembly?

Flex PCB assembly enables modern medical electronics to achieve levels of compactness, reliability, and functionality that rigid boards alone cannot support. Flexible circuits use polyimide substrates that bend, twist, or fold without breaking electrical continuity—making them ideal for devices implanted in the human body or worn close to the skin.

Flex PCB assembly requires specialized materials, equipment, and soldering control:

Components are mounted onto thin polyimide substrates rather than rigid FR4.
Circuits can fold into 3D structures to maximize internal space.
Carriers and stiffeners are used during assembly to prevent stretching and distortion.
Reflow soldering profiles are tuned for thin, heat-sensitive materials.
The design supports repeated flexing without cracking copper traces or weakening solder joints.

In medical applications, Flex PCB assembly enables ultra-lightweight designs for tools such as insulin pumps, pacemakers, imaging modules, hearing aids, surgical instruments, and continuous monitoring devices.

Flex PCB technology has become the backbone of miniaturized medical electronics, where every millimeter matters and long-term reliability is non-negotiable.

Table: Comparison of Flex PCB vs. Rigid PCB Characteristics

Characteristic	Flex PCB	Rigid PCB
Thickness	0.1-0.3 mm	1.6 mm+
Weight	Lightweight	Moderate to heavy
Bend Capability	100,000+ cycles	None
Space Efficiency	High	Moderate
Vibration Resistance	Excellent	Poor to moderate
Assembly Complexity	Integrated approach	Multi-step

How Does the Flex PCB Manufacturing Process Influence Final Assembly Quality?

The upstream fabrication process directly determines whether the final Flex assembly will survive medical use. Quality is affected by substrate chemistry, copper type, etching precision, and final surface finishing.

Key factors during manufacturing:

Material purity
Medical-grade polyimide must withstand heat, chemical exposure, and repeated sterilization cycles without degrading.
Copper selection
Rolled annealed (RA) copper is preferred because its grain structure resists cracking during dynamic bending better than electro-deposited (ED) copper.
Dimensional accuracy
Tight etching control produces consistent trace width and thickness—critical for devices with high-frequency or low-noise requirements (ultrasound, ECG modules, imaging sensors).
Laser via formation
Precision drilling ensures microvias maintain conductivity and structural strength throughout thousands of bending cycles.
Surface finish quality
ENIG (Electroless Nickel Immersion Gold) or soft gold finishes provide stable solderability and better corrosion resistance under medical conditions.

Assembly quality is only as good as the fabrication process that precedes it. Any manufacturing defect is magnified when the device is used in a hospital, operating room, or implanted inside the human body.

Why Do Engineers Choose Rigid Flex PCB Assembly for Medical Applications?

Rigid-flex PCBs integrate rigid sections for high-density component mounting with flexible interconnects that navigate compact medical housings. This hybrid architecture delivers exceptional electrical, mechanical, and spatial advantages.

Why engineers select rigid-flex for medical devices:

Eliminates connectors and cables
Every connector removed equates to one less potential failure point—critical for life-supporting equipment.
Superior electrical performance
Continuous copper paths ensure clean signals for medical imaging, sensing, and telemetry systems.
True 3D routing
Allows electronics to wrap around curves or fit into cylindrical or irregular implants.
High durability
Rigid-flex structures tolerate movement, vibration, and handling during surgery or patient activity.
Long service life
Especially important when devices remain implanted for years.

Medical devices such as neurostimulators, pacemakers, endoscopes, robotic surgical tools, handheld scanners, and portable ultrasound systems rely heavily on rigid-flex PCBs for their unmatched combination of stability and flexibility.

Table: Medical Applications Benefiting from Rigid-Flex PCB Assembly

Medical Application	Rigid-Flex Benefits	Key Considerations
Implantable Devices (pacemakers, neurostimulators)	Ultra-compact, high reliability	Hermetic sealing, long-term stability
Surgical Instruments (endoscopes, robotic tools)	Dynamic flexing, tight-space routing	Bend radius control, chemical resistance
Diagnostic Imaging (portable ultrasound, MRI)	Clean signals, compact layout	Impedance control, EMI management
Wearable Monitors (ECG patches, glucose sensors)	Lightweight, comfortable, stable	Flex endurance, moisture resistance
Medical Analyzers (blood analysis, sequencing)	High precision, stable operation	Thermal management, signal integrity

What Are the Key Steps in a Standard Flex PCB Assembly Process From Start to Finish?

Flex PCB assembly requires a tighter process window compared with rigid PCB assembly due to material thinness, dimensional sensitivity, and bend requirements.

A typical medical Flex PCB assembly sequence includes:

1. Pre-Bake and Moisture Removal

Polyimide absorbs moisture; if left untreated, it causes delamination during reflow.
Baking stabilizes the material and prevents blistering.

2. Solder Paste Application

Custom stencils and backing carriers ensure accurate printing.
Prevents deformation of the flexible substrate during paste deposition.

3. Component Placement

Pick-and-place machines are calibrated for extremely thin boards.
Carriers prevent bending under vacuum nozzles and mechanical pressure.

4. Reflow Soldering

Uses gentle thermal ramp-up to protect the flexible substrate.
Nitrogen atmosphere improves solder quality and reduces oxidation.
Multiple zones allow precise temperature control.

5. Inspection

AOI checks solder joints and placement accuracy.
X-ray identifies BGA voids and hidden solder issues.

6. Functional & Reliability Testing

Electrical continuity testing.
Flex-cycle endurance tests simulate repeated bending.
Thermal cycling validates long-term stability.

Medical-grade assemblies often undergo stricter testing than commercial devices, as patient safety depends on flawless performance.

How Can a Flex PCB Design for Assembly Guide Reduce Bending Stress and Improve Yield?

Effective design for assembly (DFA) guidelines reduce stress points, prevent cracking, and increase long-term reliability.

Key DFA principles:

1. Proper Bend Radius

Dynamic flexing: minimum 10× thickness
One-time bending: minimum 6× thickness
Exceeding these minima significantly extends product lifespan.

2. Bend Area Layout Rules

Use curved traces instead of sharp corners.
Route traces perpendicular to the bend axis.
Avoid via holes in bend regions.
Taper conductors to distribute stress more evenly.

3. Stiffener Placement

FR4 or polyimide stiffeners reinforce component areas.
Stiffeners prevent solder joint cracking during flexing.

4. Material Choice

Adhesiveless laminates improve dynamic flex life.
Biocompatible coatings support implantable designs.

Applying these rules early reduces rework, improves manufacturing consistency, and protects the assembly during real-world medical use.

Why Is PCB Assembly China a Preferred Choice for Flexible Circuit Production?

China is a leading global hub for Flex PCB and rigid-flex PCB assembly, especially for high-reliability applications like medical devices.

China’s key strengths:

Advanced factory capabilities
Laser drilling, high-precision AOI, X-ray inspection, and specialized SMT for flexible substrates.
Highly integrated supply chain
Local production of polyimide sheets, adhesives, stiffeners, and high-end electronic components.
Medical-grade quality systems
Many factories operate under ISO 13485 and support FDA documentation requirements.
Rapid prototyping and mass scaling
Efficient transitions from sample to volume production.
Cost advantages without compromising quality
Scale, process maturity, and high yields keep prices competitive.

These combined advantages make China a strategic manufacturing choice for medical OEMs aiming for excellence and cost balance.

What Should You Look for When Selecting a Professional Flex PCB Assembly Manufacturer?

Your manufacturing partner directly influences device reliability, regulatory success, and long-term product stability. Choosing correctly is essential.

Criteria when evaluating a manufacturer:

Medical certifications
ISO 13485, ISO 9001, and proven experience with medical documentation.
Technical capabilities
Multilayer Flex, rigid-flex, controlled impedance, microvia processing.
Test infrastructure
AOI, X-ray, flying probe, environmental stress screening, flex-cycle testing.
Engineering collaboration
Early DFM/DFA and stackup consultation to avoid future design risks.
Traceability and documentation
Full material lot tracking, process records, and medical-level reporting.

A qualified manufacturer acts as an engineering partner—not just a supplier—helping lift reliability and reduce design risk. Whether you need Rigid-Flex Circuits, Multilayer Flexible Circuits, Double-Sided Flexible Circuits, Dual-Access Flexible Circuits, Single-Sided Flexible Circuits, or complete assembly services, EBest Circuit (Best Technology) can provide full support. We operate our own SMT factories with fully equipped facilities in both China and Vietnam. For more information or if you would like to send us any inquiry, please send us an email through the contact form at the bottom of our Contact Page.

What Factors Shape the Overall Flex PCB Assembly Price and How Are Quotes Calculated?

Medical Flex PCB pricing reflects the complexity and reliability demands of life-critical electronics.

Main Cost Drivers:

1. Material Selection

Polyimide grade
RA copper vs. ED copper
Conformal coatings and sterilization-resistant adhesives

2. Design Complexity

Layer count
Trace/space tolerance
Microvia density
Rigid-flex transition structure

3. Testing Requirements

AOI, X-ray, flying probe
Environmental stress tests
Biocompatibility documentation

4. Volume & NRE

Tooling, stencils, fixtures
Engineering development and validation cost

By understanding these cost drivers, medical companies can design smarter, reduce wasted expense, and maintain required levels of reliability.

Table: Cost Factors in Medical Flex PCB Assembly

Cost Factor	Impact Level	Optimization Strategy
Material Selection	High	Use suitable alternatives; avoid over-spec materials
Layer Count	High	Reduce layers; consider HDI to simplify stackups
Board Size	Medium	Improve panel utilization
Tolerances	High	Specify practical tolerances only
Surface Finish	Medium	Choose finish based on real reliability needs
Testing Requirements	Medium–High	Test critical areas; combine efficient inspection methods
Documentation	Medium	Keep documentation to essential requirements

Why Choose EBest Circuit (Best Technology) for Best Rigid-Flex PCB Assembly Services for Medical Devices?

BEST Technology provides medical OEMs with fully engineered Flex and rigid-flex PCB assembly solutions built for long-term, life-critical reliability.

What makes BEST Technology a strong partner:

Decades of expertise in Flex and rigid-flex manufacturing.
Medical-grade compliance, including ISO 13485-aligned processes.
Engineering support for stackup, bend radius, materials, and DFM/DFA optimization.
Advanced inspection using AOI, X-ray, flying probe, and reliability testing.
Stable production scalability from prototypes to large volumes.
Full traceability and detailed documentation for medical regulatory needs.

BEST Technology helps medical brands deliver safe, durable, and efficient devices built on precision-engineered Flex PCB and rigid-flex technology.

In a nutshell, flex PCB assembly enables the development of advanced medical devices through its unique combination of reliability, miniaturization, and dynamic functionality. As medical technology continues advancing toward less invasive procedures and more portable equipment, flex circuit technology will play an increasingly critical role in enabling these innovations. Understanding the principles outlined in this guide empowers medical device engineers to make informed decisions that balance performance, reliability, and manufacturability throughout the product development lifecycle .

At BEST Technology, we specialize in translating these principles into reliable, production-ready medical devices through our comprehensive rigid-flex PCB assembly services. Our medical industry expertise, combined with state-of-the-art manufacturing capabilities, ensures your devices meet the rigorous standards demanded by healthcare applications. Pls feel free to contact us at sales@bestpcbs.com to discuss how our flex PCB assembly solutions can enhance your medical device projects.

Tags: Best Rigid-Flex PCB Assembly Services for Medical Devices, Flex PCB Assembly, Flex PCB Design for Assembly Guide, Flex PCB Manufacturing Process, Rigid Flex PCB Assembly, Standard Flex PCB Assembly Process
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Smartwatch PCB Design & Manufacturer, Turnkey Solution

October 10th, 2025

What is smartwatch PCB? Let’s explore definition, material selection, technical spec and guideline, production process and cost for smartwatch PCB.

Are you worried about these questions?

Does smartwatch excessive heat generation affect user experience due to conventional PCB’s inadequate heat dissipation?
How to guarantee yield rate when ultra-thin design causes PCB deformation?
Does metal casing signal interference and poor communication stability cause high return rates?

As a smartwatch PCB manufacturer, EBest Circuit (Best Technology) can provide you service and solution:

Aluminum substrate triples thermal conductivity efficiency, dropping chip temperature by 15°C to eliminate thermal discomfort.
0.8mm metal substrate withstands 10,000-cycle flexural testing without cracking, combining slim profile with durability.
Custom dielectric layer provides interference shielding, increasing Wi-Fi/Bluetooth signal strength by 20%.

Welcome to contact us if you have any smartwatch PCB: sales@bestpcbs.com.

What is Smartwatch PCB?

Smartwatch PCB utilize rigid-flex technology to create high-density miniature circuit boards. Their core function is to integrate electronic components, including main control chips, biosensors, and wireless communication modules, within extremely limited space (typically less than 30mm in diameter).

Polyimide flexible substrates enable dynamic bending adaptation to the wrist’s motion, while nanoscale anti-corrosion coatings ensure IP68 waterproof and sweatproof performance. These designs guarantee stable operation across temperatures ranging from -40°C to 85°C and support up to 100,000 bending cycles, meeting durability demands for wearable devices.

Which Material is Best for a Smartwatch PCB?

Polyimide (PI) Substrate Flexible and Lightweight Preferred

Adopts 25-50μm ultra-thin PI substrate with thickness equivalent to half a human hair diameter. Maintains elasticity from -20℃ to 120℃ and withstands 100,000 bending cycles at 5mm radius while maintaining insulation resistance above 10¹⁰Ω, far exceeding conventional FR-4’s 10⁸Ω.
Combined with 12μm rolled copper foil and arc-transition wiring design, achieves 0.07mm total thickness and weighs only 0.5g (approximately a snowflake’s weight). Perfectly suited for curved-fit and miniaturization needs of smartwatches. A flagship smartwatch achieved 40% weight reduction and 30% improvement in wear comfort compared to previous models using PI substrate.

Aluminum Substrate High-Efficiency Thermal Management Core

Features 1.5-2.0mm thick aluminum base layer with thermal conductivity of 200-250W/m·K, 250 times higher than FR-4’s 0.8W/m·K. Utilizes micro-via thermal conduction patent to rapidly transfer heat from high-power components (e.g., LEDs/power modules) to the aluminum base, reducing junction temperature by 25-40℃ and extending device life.
Commonly used in power management modules or high-power chip cooling for smartwatches. A brand smartwatch achieved 60℃ continuous operation without thermal overload and 30% improvement in heat dissipation efficiency using aluminum substrate.

Ceramic Substrate High Wear Resistance and Signal Stability

Zirconia ceramic with Mohs hardness 8.5 (close to sapphire’s 9) offers wear resistance, skin-friendliness, and hypoallergenic properties. Its dielectric constant is three times that of sapphire, reducing signal transmission loss by 50%. Nano-powder molding technology enables 0.03mm ultra-thin substrate supporting wireless charging and 5G signal penetration.
Commonly used in smartwatch cases, back covers, or high-frequency modules. A brand smartwatch achieved 20% improvement in signal sensitivity, threefold improvement in wear resistance, and two-year extension in service life using ceramic back cover.

Halogen-Free FR-4 Environmental and Cost Balance

Uses phosphorus-based flame-retardant resin and alkali-free glass cloth, complying with EU REACH standards. Heavy metal content below 10ppm and no toxic gas emission during combustion.
Commonly used in smartwatch mainboards or low-power modules, costing 15-20% less than aluminum substrate while maintaining traditional FR-4’s insulation performance and processing maturity. A children’s smartwatch achieved no allergic reactions in skin irritation tests using halogen-free FR-4.

Which Material is Best for a Smartwatch PCB?

Smart Watch PCB Technical Specification

Parameter Item	Specific Requirements
Board Material Type	High-Tg FR4 (Tg≥170℃) or High-Frequency Material (for RF areas)
Dielectric Constant (1GHz)	εr = 4.2±0.1 (core layer)
Loss Tangent (1GHz)	tanδ ≤ 0.02
Total Thickness	0.8±0.1mm (including copper foil and solder mask)
Minimum Core Thickness	≥0.1mm
Copper Foil Thickness (Outer/Inner Layer)	Outer: 18μm Hoz; Inner: 12μm
Minimum Trace Width/Spacing	60μm/60μm (L/S)
Laser Drill Hole Diameter	≥0.1mm (mechanical drill) / ≥0.075mm (laser drill)
Via Annular Ring Width	≥0.075mm
BGA Area Pad Diameter	≥0.25mm (pitch 0.4mm)
Solder Mask Bridge Width	≥0.05mm
Solder Mask Opening Expansion	Single side 0.05mm (pad)
Character Line Width	≥0.12mm
Surface Finish Type	ENIG (Ni thickness ≥3μm, Au thickness ≥0.05μm)
Pad Coplanarity	≤15μm (local area)
RF Differential Impedance (e.g., Bluetooth antenna)	90Ω±7% (with complete GND reference layer)
High-Speed Signal Single-Ended Impedance	50Ω±10%
Thermal Via Density (CPU area)	≥4 vias/mm² (hole diameter 0.2mm)
Copper Thickness (Thermal Dissipation Area)	Outer: 2oz, Inner: 1oz
Ionic Contamination Level	≤1.56μg/cm² NaCl equivalent
Thermal Stress Test	No delamination after 3 times 288℃ reflow soldering
Gold Plating Thickness (charging/data interface)	≥0.2μm Au (Ni underlayer ≥3μm)
Mating/Unmating Life	≥5000 cycles
Electrical Test Coverage	100% Net
Flying Probe Test Minimum Pitch	≥0.15mm
Flex Area (if applicable)	Bend radius ≥5mm, cycle life ≥10000 times
Waterproof Sealing Area	Solder mask opening width ≤0.1mm
Process Edge Width	≥5mm (per side)
Mark Point Quantity	Diagonal ≥2 points, spacing ≥70% of board length

How to Design a Smartwatch PCB Board?

Below is a guide to smartwatch PCB design:

1. Requirement Analysis and Function Definition

Core Function Clarification: Define essential modules including heart rate monitoring, GPS positioning, Bluetooth/Wi-Fi communication, NFC payment, motion sensors (accelerometer/gyroscope), display drivers, and haptic feedback.
Quantified Performance Metrics: For example, battery life ≥3 days (typical usage), charging time ≤2 hours, operating temperature range -20℃~60℃, waterproof rating IP68.
User Scenario Alignment: Optimize designs for sports, medical, and daily wear scenarios—e.g., enhance GPS accuracy and real-time heart rate monitoring for sports, meet biocompatibility standards for medical use.

2. Component Selection and Integration Optimization

Main Controller Chip: Prioritize low-power SoCs (e.g., ARM Cortex-M series) integrating GPU, memory controller, and PMU to reduce external components.
Sensor Integration: Use modular designs (e.g., 6-axis IMU, optical heart rate sensors) while avoiding magnetic interference sources (speakers/motors) in layout.
Power Management Solution: Adopt high-efficiency DC-DC converters (e.g., Buck converters) and LDOs, paired with battery protection chips (overcharge/discharge/short-circuit protection).
Wireless Module Layout: Keep Bluetooth/Wi-Fi antennas away from metal shields; use FPC flexible antennas or ceramic antennas to ensure signal integrity.

3. PCB Layout and Stack-up Design

Layer and Material Selection: Recommend 6–8-layer boards (2 signal layers + 2 power layers + 2 ground layers) with FR-4 or high-frequency substrates (e.g., Rogers 4350B); surface finish ENIG for soldering reliability.

Layout Principles:

Module Partitioning: Separate digital circuits (MCU, memory), analog circuits (sensors, audio), and power circuits to minimize crosstalk.
Critical Path Optimization: High-speed signals (e.g., USB, MIPI DSI) ≤5cm trace length, differential pairs (100Ω±10% impedance), avoid via cross-split planes.
Component Placement: Place heat-generating components (PMUs, power amplifiers) near heat-dissipation zones; sensitive devices (crystals, ADCs) away from noise sources.
Ground Plane Partitioning: Single-point connection for digital/analog grounds via beads or 0Ω resistors to reduce ground bounce noise.

4. Power Management Design

Multi-Voltage Domain Management: Core MCU voltage (1.8V/3.3V), sensor power (1.2V/1.8V), display backlight (5V/12V) via LDO/DC-DC conversion.
Low-Power Design: Implement DVFS, sleep modes (<10μA standby current), and power sequencing control.
Battery Protection: Integrate over-voltage/under-voltage circuits with Li-ion protection ICs (e.g., DW01A) to prevent aging or safety issues.

5. Signal Integrity and EMI/EMC Design

Impedance Control: Match 50Ω/100Ω impedance for high-speed lines via stack-up calculations (trace width/spacing).
Crosstalk Suppression: Shield sensitive signals (analog sensors) or use ground wraps; maintain ≥3× trace width spacing.

EMC Protection:

Add TVS diodes (ESD protection) to input ports (e.g., charging ports).
Use π-type filters (capacitor-inductor-capacitor) for RF modules to reduce conducted/radiated noise.
Shield high-frequency modules (Wi-Fi chips) with metal covers to minimize EMI leakage.

5. Thermal Management Design

Thermal Path Planning: Under high-power chips (MCUs, PMUs), deploy large copper pads connected to metal enclosures via thermal pads/grease.
Thermal Simulation: Validate junction temperature ≤125℃ (chip safety) and surface temperature ≤45℃ (human contact safety) using tools like ANSYS Icepak.
Passive Cooling: Add graphene heat sinks on PCB backsides; optimize airflow channels (e.g., watch case vents).

6. Manufacturability and Reliability Design

DFM/DFA Rules: Component spacing ≥0.2mm (avoid solder bridges); IPC-compliant pads (e.g., QFN thermal pads); SMT-compatible packages (0402/0603).
Reliability Testing: Validate PCB durability via thermal cycling (-40℃~85℃), vibration (IEC 60068-2-6), and salt spray (ASTM B117) tests.
BOM Optimization: Reduce material types (unify capacitor/resistor brands); prioritize automotive/industrial-grade components.

7. Testing and Verification Process

Prototype Validation: Test functions (button response, display brightness), power (current consumption, voltage ripple), and signals (eye diagram, timing) on engineering samples.
EMC Certification: Meet standards like CISPR 32 (radiated emissions) and IEC 61000-4-2 (ESD immunity).
Mass Production Inspection: Perform AOI, X-ray, and functional sampling on batched PCBs to ensure consistency.

8. Packaging and Protection Design

Waterproofing: Apply conformal coating (silicone resin) to PCB edges; use waterproof sealants on connectors; add O-rings between cases and PCBs.
Shock Resistance: Secure critical components (crystals, connectors) with adhesive to prevent vibration-induced detachment.
User Interface Protection: Add ESD circuits to touchscreens; use metal dome switches for button interfaces to enhance contact reliability.

How to Manufacture a Smart Watch PCB?

1. Design Output

Use Altium Designer/OrCAD to complete circuit design, must include heart rate monitoring, GPS positioning, and other modules.
Gerber files contain signal layer/power layer/ground layer layouts, Excellon drilling files, and solder mask/silkscreen data.
BOM (Bill of Materials) must specify component models, package dimensions, and procurement channels to ensure traceability.
Perform DFM (Design for Manufacturing) verification during the design phase to avoid issues like excessively small line widths/spaces or defective pad designs.

2. Substrate Preparation

For high-frequency scenarios, use Rogers 4350B or Panasonic Megtron 6; FR-4 is used for cost-sensitive applications.
Copper-clad laminate cutting accuracy ±0.1mm, using automatic cutting machines to avoid burrs.
Copper thickness 1oz (0.035mm) or 2oz (0.07mm); high-power areas use 2oz for enhanced heat dissipation.
Clean substrates to remove oil and oxidation layers, ensuring adhesion for subsequent processes.

3. Inner Layer Circuit Fabrication

Use LDI (Laser Direct Imaging) technology for pattern transfer with ±5μm accuracy, avoiding film exposure errors.
UV exposure energy 80-120mJ/cm², developer concentration 10-15% Na₂CO₃, temperature 30-35°C.
Etching solution uses acidic copper chloride, temperature 45-50°C, speed 1.2-1.5m/min, ensuring neat line edges.
AOI (Automated Optical Inspection) testing uses 3D imaging technology with ±10μm accuracy to detect opens, shorts, and copper deficiencies.

4. Lamination Molding

Symmetrical stack-up design (e.g., core board + prepreg + copper foil) to avoid warping after lamination.
Vacuum lamination temperature 180-200°C, pressure 300-400psi, time 90-120 minutes.
Prepreg uses high-Tg material (e.g., Shengyi S1141) to prevent delamination during reflow soldering.
Post-lamination X-ray inspection for interlayer alignment accuracy ≤50μm.

5. Drilling

Laser drilling uses CO₂ laser, hole diameter ≤0.1mm, suitable for HDI (High Density Interconnect) board blind/buried vias.
Mechanical drilling uses minimum 0.2mm drill bit, speed 80,000rpm, feed rate 0.5m/min.
Plasma etching after drilling to remove debris, ensuring clean hole walls.
Positioning holes use pin alignment with ±0.05mm accuracy for subsequent assembly alignment.

6. Hole Metallization

Chemical copper deposition thickness 1-2μm to form a conductive base; electroplated copper thickness 25-30μm to avoid voids.
Electroplating uses pulse power, backlight inspection ≥8 levels to ensure uniform hole plating.
Hole wall roughness Ra ≤2μm to reduce signal transmission loss.

7. Outer Layer Circuit

Outer layer pattern transfer uses LDI technology with ±5μm accuracy to ensure circuit precision.
Secondary AOI testing uses high-speed line scanning to detect line width/space deviations and copper deficiencies.
Outer layer circuits undergo anti-oxidation treatment (e.g., nickel-gold plating) to prevent oxidation affecting soldering.
Plasma cleaning of circuit edges enhances solder mask adhesion.

8. Solder Mask & Silkscreen Printing

Solder mask uses liquid photoimageable ink (e.g., Taiyo PSR-4000), coating thickness 20-30μm, soldering temperature resistance 260°C.
Exposure uses UV LED with 300-500mJ/cm² energy to ensure complete ink curing.
Silkscreen printing uses white ink with font height ≥0.2mm for readability.
Solder mask opening accuracy ±0.05mm to avoid pad misalignment.

9. Surface Finish

ENIG (Electroless Nickel Immersion Gold) uses 4-6μm nickel + 0.05-0.1μm gold to enhance solder reliability.
OSP (Organic Solderability Preservative) uses organic film with 0.2-0.5μm thickness, cost-effective but with a 6-month shelf life.
Post-surface finish, perform solderability testing (e.g., wetting balance) to ensure welding performance.
High-reliability products use ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold) for enhanced high-frequency signal stability.

10. Testing & Depanelization

Electrical testing uses flying probe (±0.02mm accuracy) or bed-of-nails (contact resistance ≤0.1Ω) to verify circuit connectivity.
Impedance testing uses TDR (Time Domain Reflectometry) to ensure high-frequency signal line impedance matching (e.g., Bluetooth antenna ±10%).
V-CUT depanelization uses milling cutter with ±0.1mm accuracy to avoid burrs affecting assembly.
Post-depanelization, perform ionic contamination testing (e.g., ROS-120) to ensure cleanliness.

11. Final Inspection & Packaging

Visual inspection uses AOI or manual methods to detect defects like scratches, deformation, or color discrepancies.
Vacuum moisture-proof packaging uses aluminum bags + desiccant with humidity ≤5% to prevent oxidation.
Packaging includes production date, batch number, and environmental compliance markings (e.g., RoHS) for traceability.
Final products undergo environmental testing (e.g., high-temperature/humidity, thermal shock) to ensure reliability.

How Much Does it Cost to Make a Smartwatch PCB?

The manufacturing cost of smartwatch PCBs is strictly affected by the number of layers, materials, and process complexity, and the price is calculated based on the unit price of an order of 1,000 pieces: the basic model uses a 4-layer FR-4 board and conventional process, with a single board cost of approximately $8-15, suitable for entry-level smartwatches; the mid-to-high-end model is upgraded to a 6-8-layer HDI board and uses high-frequency materials, with the cost climbing to $25-50, which must meet the high-precision requirements of Bluetooth/Wi-Fi/GPS multi-mode radio frequency.

If the model uses a flexible PCB + ultra-thin design combined with laser drilling and immersion gold technology, with a unit price of up to $60-120. Its core cost drivers are concentrated on ±5% impedance control accuracy and miniaturized component placement technology. It is worth noting that if the order volume is less than 1,000 pieces, the unit price will increase by 30%-50%, which further highlights the key balancing role of precision manufacturing technology and large-scale production in cost control.

Why Choose EBest Circuit (Best Technology) as Smartwatch PCB Manufacturer?

Reasons why choose us as smartwatch PCB manufacturer:

19-Year Expertise Vault: 19 years of PCB manufacturing expertise and error database-driven risk prediction reduce rework costs by 5%-10% per order, turning experience into tangible savings.
Global Certification: ISO 19001, IATF 16949 automotive-grade, medical-grade, and RoHS, which guarantee compliance with global market entry requirements, enabling seamless international market access.
Free DFM Technology: Complimentary Design for Manufacturability analysis identifies design flaws and process risks upfront, cutting mass production preparation time by 30% and costs by 20%, ensuring design excellence.
Full Turnkey Solution: Integrated PCB fabrication, component sourcing, SMT assembly, and functional testing streamline supply chain management by 40%, allowing clients to focus on core innovation.
24 Hours Rapid Prototyping: 24-hour rapid prototyping for urgent orders, compressing design-to-prototype cycles to 1 day, accelerating product iteration, and delivering “first-mover” commercial advantage.
Revolutionary Cost Optimization: Leverage intelligent material selection and process streamlining to achieve 15%-30% single-board cost reduction, enabling price competitiveness across entry-level to flagship smartwatch segments and securing high-value market share.
Unmatched Delivery Reliability: 99.2% on-time delivery rate powered by AI-driven smart scheduling and global supply chain collaboration, eliminating delivery risks and ensuring production peace of mind.
Strict Quality Commitment: 100% batch inspection coverage with AOI/X-Ray/functional testing, achieving 99.9% yield rate and superior performance consistency, far exceeding industry standards.
RF Expertise for Multi-Mode Connectivity: Master HDI laser drilling, immersion gold, and ±3% impedance control to support Bluetooth/Wi-Fi/GPS multi-mode RF demands, enhancing signal integrity by 20% and outperforming competitors.

How to Start a Smart Watch PCB Project?

Quotation Checklist for Smartwatch PCB Project:

1. PCB Specifications

Layer count (e.g., 4/6/8 layers)
Material type (FR-4, HDI, or flexible PCB)
Board thickness and impedance control requirements.

2. Components & Assembly

BOM (Bill of Materials) cost for ICs, sensors, and connectors.
SMT (Surface Mount Technology) assembly fees.
Testing and quality control charges.

3. Design & Engineering

Schematic and layout design fees.
RF/wireless module integration costs (Bluetooth/Wi-Fi/GPS).

4. Production & Logistics

Prototyping cost (e.g., 5-10 boards).
Bulk production MOQ (Minimum Order Quantity) and unit price.
Shipping and import duties (if applicable).

5. Additional Services

Certification compliance (FCC, CE, etc.).
IP protection (NDA or custom firmware costs).

Welcome to submit your Gerber files to get a quote for you now: sales@bestpcbs.com.

Tags: smartwatch PCB
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What is bendable aluminum substrate? Flexible Aluminum PCB

August 15th, 2025

Bendable aluminum substrate is a metal-based copper-clad laminate with folding or bending functions. It is bent and shaped through a special process. It has the advantages of good thermal conductivity, lightweight, and bending resistance. It is mainly used in the bendable structure of LED lamps and lightweight foldable components of electronic devices such as mobile phones.

What is bendable aluminum substrate? Flexible Aluminum PCB

Are you curious about:

What are the core advantages of bendable aluminum substrates?
How many bends can they last?
What is their heat dissipation performance?
What applications are they generally suitable for?

BEST Technology can provide you with high-performance bendable aluminum substrates. Our aluminum substrates offer the following properties:

High heat dissipation from the aluminum substrate combined with flexibility and bendability, ensuring both heat dissipation and surface adaptability.
Dynamic bending resistance of ≥80,000 times (R=1.5mm), ensuring continuous circuitry.
The aluminum substrate’s thermal conductivity and high adhesive layer provide a thermal resistance of ≤1.0°C/W, improving heat dissipation by 25% or more compared to ordinary flexible substrates.
LED flexible light strips, curved automotive lights, wearable devices, and other applications require both bending and heat dissipation.

What is flexible aluminum substrate?

Flexible aluminum substrate is a special type of circuit board base that uses bendable aluminum as its core layer. Unlike traditional rigid aluminum PCBs, these substrates are engineered to withstand controlled bending without cracking or losing structural integrity.

In PCB manufacturing, the substrate acts as the backbone. It supports copper traces, dissipates heat, and maintains mechanical stability. With bendable aluminum, you get all the advantages of aluminum’s high thermal conductivity and durability—plus the added ability to shape or curve the board during assembly or installation.

This property is particularly valuable in LED lighting strips, automotive electronics, aerospace control systems, and wearable devices. It allows products to fit into tighter spaces, wrap around surfaces, or follow curved housing designs without sacrificing performance.

What grades of bendable aluminum sheets are available?

Not all aluminum grades can be bent easily. The alloy composition and temper determine flexibility. Here are common grades relevant to PCB substrates:

1050 and 1100 Series

High-purity aluminum with excellent corrosion resistance.
Very good bendability, suitable for tight radius bends.
Often used for applications needing high ductility.

3003 Aluminum

Alloyed with manganese for better strength than 1100.
Maintains good bending properties.
Common in lighting and decorative PCB applications.

5052 Aluminum

Stronger than 3003, with excellent corrosion resistance.
Good formability, works well for medium bend radii.
Often selected for outdoor electronics or marine-grade designs.

6061 Aluminum

High strength but less ductile than 5xxx series.
Bendable in annealed tempers (O-temper) but more difficult in T6.
Ideal for structural applications where mechanical strength is critical.

6063 Aluminum

Good surface finish and corrosion resistance.
Easier to bend than 6061 in certain tempers.
Often used in heat sink-integrated boards.

Key takeaway: When choosing a grade, balance strength, bend radius, and thermal performance. In PCB manufacturing, 3003, 5052, and 6063 are common for bendable aluminum substrates.

How to test a bendable aluminum sheet?

Testing ensures the sheet meets your mechanical and thermal requirements before it becomes part of a PCB. Here are standard methods:

Bend Test: The sheet is bent to a specified radius and checked for cracks or surface deformation. For PCBs, smaller radii require more ductile alloys.

Elongation Test: Measures how much the aluminum can stretch before breaking. Higher elongation values mean better bendability.

Hardness Test: Indicates resistance to deformation. Softer aluminum generally bends more easily.

Thermal Cycling Test: Exposes the material to repeated heating and cooling to simulate operating conditions.

Surface Adhesion Test: Checks how well dielectric and copper layers adhere after bending.

These tests help engineers confirm that flexibility does not compromise thermal conductivity or copper adhesion.

How to make bendable aluminum substrate?

The process combines materials science and precision PCB manufacturing.

Select the Aluminum Core: Choose the alloy and thickness based on bending needs. Thinner cores bend more easily but handle less load.

Apply the Dielectric Layer: High thermal conductivity insulation is laminated onto the aluminum. Materials like polyimide or flexible epoxy composites are used.

Add Copper Foil: The copper layer is laminated and patterned through photolithography and etching.

Protect with Solder Mask: Flexible solder mask layer shields the copper and dielectric.

Final Forming: Boards may be partially formed before delivery, or bent during final assembly.

Special care is needed in temperature control, lamination pressure, and adhesive selection. Poor processing can cause delamination when bending, so experienced BEST Technology use advanced bonding techniques.

What are the benefits of bendable aluminum substrate?

The benefits go beyond just flexibility:

Superior Heat Dissipation: Aluminum’s high thermal conductivity allows efficient heat transfer away from heat-generating components.

Lightweight Strength: Maintains structural integrity even at reduced thickness.

Design Freedom: Enables curved or irregular shapes without multiple rigid sections.

Long Service Life: Resistant to corrosion, vibration, and impact.

Reduced Assembly Costs: A single bendable board can replace multiple interconnected rigid boards.

For manufacturers, this means better performance and simpler mechanical integration. For buyers, it means lower total cost and fewer failure points.

What are the applications of bendable aluminum substrate?

Applications span high-reliability and thermally demanding fields:

LED Lighting: Flexible mounting in architectural, automotive, and display lighting.

Automotive Electronics: Curved dashboard PCBs, lighting assemblies, and under-hood electronics.

Aerospace Systems: Weight-saving designs that fit tight spaces.

Wearable Medical Devices: Flexible yet robust circuits for monitoring and control.

Industrial Controls: Machines that require boards to wrap around mechanical housings.

In each case, the bendable aluminum substrate provides both mechanical adaptability and reliable heat management.

Does bending reduce the strength of aluminum substrate?

Yes, but the effect depends on alloy, temper, and bend radius. When aluminum is bent, it undergoes work hardening, which increases strength in the bend area but can also reduce ductility.

If bending exceeds the material’s formability limit, micro-cracks can form, reducing fatigue life. That’s why BEST Technology design for the proper bend radius based on alloy properties and thickness.

In practice, when using recommended bend parameters and high-quality processing, the strength loss is minimal for most PCB applications.

Why choose BEST Technology to make bendable aluminum substrates?

BEST Technology Co., Ltd. has been a trusted PCB and substrate manufacturer since 2006. We understand that buyers need more than just a supplier—they need a partner who delivers consistent quality.

Our advantages:

Material Expertise: We work with multiple aluminum grades, ensuring the right balance of flexibility and performance.

Precision Manufacturing: Our process maintains ±0.05mm dimensional accuracy, even in bendable designs.

Thermal and Mechanical Reliability: Each substrate undergoes strict bend, adhesion, and thermal tests.

Fast Turnaround: Average delivery in 7 days, faster than the industry standard.

Global Experience: Serving industries in Asia, Europe, and North America with OEM and ODM capabilities.

When you choose BEST Technology, you get a bendable aluminum substrate designed to last—and a team committed to your project’s success.

Do you need BEST Technology to make a bendable aluminum PCB for you? We are waiting for your information, please contact us: sales@bestpcbs.com

Tags: bendable aluminum plate, bendable aluminum substrate
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What is Rigid-Flex Copper Substrate? Rigid Flex PCB

August 14th, 2025

Rigid-flex copper substrate combines the best of both rigid PCBs and flexible circuits into a single circuit board. This design is both practical and innovative. Its applications range from advanced medical devices to aerospace systems. Its versatility stems from the way its copper layer is integrated with both flexible and rigid components, enabling smooth folding without disrupting connections.

What is Rigid-Flex Copper Substrate? Rigid Flex PCB

Do you want to know:

What are its advantages over ordinary substrates?
How many frequent bends can it withstand?
How is heat dissipation guaranteed?
Does it support complex circuits and unusual shapes?
What is the prototype production cycle?
What are the quality standards?

BEST Technology, a professional metal-based circuit board manufacturer, can answer your questions:

The high heat dissipation of a rigid substrate combined with the flexibility of a flexible substrate allows for complex applications.
Dynamic bending resistance of ≥100,000 times (R=1mm) ensures continuous circuitry and stable performance.
Highly conductive adhesive layer combined with a full copper surface design results in a thermal resistance of ≤0.8°C/W, improving heat dissipation by 30%+ in high-temperature environments.
Minimum line width/spacing of 3 mils, supports unusual shapes and stepped structures, and an accuracy error of ≤±0.1 mil.
Prototypes take 3 days, and mass production takes 7-15 days. Compliant with IPC-A-600H, with over 20 tests and 24-hour customer service.

What is rigid-flex copper substrate?

Rigid-flex copper substrate is a hybrid printed circuit board that has rigid and flexible layers combined into one structure. The rigid parts provide mechanical stability, while the flexible layers connect them, allowing bending or folding during assembly or use.

This combination removes the need for connectors or separate ribbon cables, reducing the risk of signal loss or failure. In many designs, rigid-flex boards improve reliability and performance at the same time.

The rigid flex PCB design typically uses copper foil as the conductor. Copper is preferred because it offers excellent conductivity, mechanical strength, and resistance to fatigue. The result is a board that can bend without losing electrical integrity.

Rigid-flex copper substrate with different layers

Layer count in a rigid-flex board greatly impacts performance, cost, and applications.

1. 2-layer rigid-flex copper substrate

This is the simplest form. It offers enough flexibility for basic designs and is often used in consumer devices, portable gadgets, and small control panels. It’s affordable and fast to produce.

2. Dual-layer rigid-flex copper substrate

Similar to the 2-layer version but often built with reinforced materials. It provides more strength and is ideal for designs that require slight bending during use.

3. 4-layer rigid-flex copper substrate

With more copper layers, it allows complex routing, better signal performance, and improved EMI shielding. The 4-layer copper-based rigid-flex PCB is common in automotive electronics and handheld medical devices.

4. 6-layer rigid-flex copper substrate

This high-end design is built for advanced technology. It supports multiple high-speed signals, complex interconnections, and precise impedance control. Aerospace systems, industrial control machines, and military electronics often use this type.

Choosing the right layer count depends on design needs, available space, and budget. Each option balances performance and flexibility differently.

How does rigid flex PCB work?

The rigid flex PCB works by integrating multiple circuit layers—some rigid, some flexible—into one laminated structure. During manufacturing, the flexible layers are bonded with polyimide material, while the rigid parts are reinforced with FR4 or other stiffeners.

When installed, the flexible sections bend to fit inside tight enclosures. This makes it perfect for 3D assembly. The electrical signals flow through copper traces that remain continuous across the rigid and flexible areas, eliminating the need for connectors.

By reducing interconnections, rigid flex PCBs lower the risk of mechanical failure, improve signal speed, and make products more reliable in harsh conditions.

Why choose rigid-flex copper substrate?

There are many reasons to choose a rigid-flex copper substrate.

Space efficiency: This design allows components to be placed closer together, reducing product size.

Durability: Flexible sections handle repeated bending without breaking. This is important in devices exposed to motion or vibration.

Improved performance: Fewer connectors mean faster signal transmission and less interference.

Lightweight construction: Replacing multiple boards and cables with one unit cuts down weight.

Design freedom: Three-dimensional design is possible, allowing for better utilization of interior space.

From smartphones to satellites, rigid-flex boards help achieve higher performance without increasing size.

Which flexible PCB material is best?

The performance of a rigid-flex PCB depends heavily on the flexible material. Most use flexible circuit technologies with polyimide films, which offer excellent heat resistance, flexibility, and electrical insulation.

Polyimide is also stable in harsh environments, making it a trusted choice for aerospace, automotive, and industrial applications. For added strength, some designs use adhesive-less laminates, which improve bending capability and reduce thickness.

Copper foil is the heart of the conductor. Rolled annealed copper is preferred for its flexibility and fatigue resistance, while electro-deposited copper works well for more rigid applications.

The choice of flexible PCB material depends on the final product’s environment, electrical needs, and mechanical requirements.

How durable is flexible PCB material?

Flexible PCB materials are surprisingly tough. High-quality polyimide can handle thousands of flex cycles without cracking. Even in high-temperature or high-vibration environments, it maintains structural integrity.

Durability also depends on copper type, layer thickness, and protective coatings. Protective coverlays shield copper traces from moisture, dust, and abrasion. When designed correctly, a rigid-flex PCB can last as long as the device itself.

It’s worth noting that durability is not just about materials—it’s also about design. Proper bend radius, trace routing, and reinforcement all increase lifespan.

How does rigid flex PCB save space?

One of the biggest advantages of rigid-flex PCBs is their space-saving ability. By combining rigid and flexible sections into one board, you remove the need for bulky connectors and cables.

This allows components to be stacked closer or arranged in creative ways. Devices can be slimmer, lighter, and easier to assemble. For example, in wearables or medical implants, every millimeter counts. The space saved often translates directly into more battery capacity, extra features, or lighter designs.

For manufacturers, fewer components mean faster assembly and fewer points of failure.

What affects rigid-flex copper substrate cost?

Cost can vary widely depending on several factors:

Layer count: More layers mean more complex manufacturing, which increases price.

Material choice: Premium copper foils and polyimide films cost more but offer better performance.

Size and shape: Complex shapes require more precise processing.

Production volume: Higher quantities often reduce per-unit cost.

Testing requirements: Rigid-flex boards for aerospace or medical devices require strict quality control, adding to cost.

Working with a skilled flex PCB manufacturer ensures cost efficiency without compromising quality. BEST Technology will help you choose the best PCB stackup, optimize the number of layers, and select the most suitable flexible PCB material for your needs.

Need Rigid-Flex Copper Substrate? BEST Technology can help you， contact sales@bestpcbs.com

Tags: flex pcb manufacturer, flexible pcb material, rigid flex pcb, Rigid-flex copper substrate
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What is Rigid-flex aluminum substrate? Aluminum Flex-Rigid PCB

August 8th, 2025

What is a rigid-flex aluminum substrate?

Rigid-flex aluminum substrate is a hybrid PCB structure that combines rigid and flexible sections, with aluminum used as a thermal-conductive base. Think of it as a single circuit board with areas that bend and fold—yet it stays strong and dependable under pressure.

What is Rigid-flex aluminum substrate? Aluminum Flex-Rigid PCB

Unlike traditional rigid PCBs, this type doesn’t rely solely on fiberglass or FR4. Instead, it mixes rigid substrates (like aluminum for heat dissipation and strength) with flexible layers (usually made of polyimide). These parts are layered together in a rigid flex stackup to create a solid yet adaptable foundation.

The aluminum core enhances performance, especially in high-power or high-temperature environments. The flexible sections allow the board to fit into tight or curved enclosures—perfect for compact designs.

What is the rigid flex process?

Creating a rigid-flex aluminum substrate involves multiple, tightly controlled steps. This process ensures the reliability and functionality of each part, from the stiff aluminum core to the bendable flex areas.

Here’s how it works:

Material Preparation: Aluminum is selected as the rigid base layer. Polyimide films are chosen for the flex sections. Copper foil is used for the conductive pathways.

Layering: These materials are laminated together in a multi-layer PCB stackup, carefully aligning the rigid and flexible parts. Adhesives must tolerate both mechanical stress and high heat.

Drilling and Plating: Vias are drilled to connect layers. These vias are plated with copper to ensure stable electrical performance between rigid and flexible sections.

Etching and Imaging: Circuit patterns are etched into the copper layers.

Coverlay and Protection: The flex parts are protected with a coverlay—a thin film that protects the flexible circuit from damage or oxidation.

Testing: Each board goes through strict electrical and mechanical testing to ensure it can bend without breaking and still conduct flawlessly.

This precise rigid flex process demands high skill and advanced machinery.

Rigid-flex aluminum substrate Types

Depending on your application, several types of rigid-flex aluminum substrates are available. Each is designed for specific environments and use cases.

Single-Sided Rigid-Flex: One layer of copper on the flexible section. Simple and cost-effective.

Double-Sided Rigid-Flex: Copper on both sides of the flex section for increased routing options.

Multi-Layer Rigid-Flex: Complex designs with 4+ layers, often used in aerospace, medical, and high-end automotive electronics.

Hybrid Stackups: Combine aluminum with other rigid materials (like FR4 or CEM-3) for specific mechanical or thermal goals.

Each type has trade-offs in cost, thickness, and flexibility. But with aluminum in the core, they all shine in thermal management and durability.

Rigid-flex aluminum substrate Benefits

Rigid-flex aluminum substrate combines the advantages of rigidity and flexibility.

1. Thermal Conductivity

Aluminum is an excellent heat conductor. It keeps your circuits cool even when running at full power.

2. Space Saving

With a rigid-flex structure, you can fold or twist the board to fit inside small or oddly shaped enclosures.

3. Mechanical Strength

The rigid aluminum base offers strong mechanical support. It doesn’t warp or bend easily.

4. Improved Reliability

Fewer solder joints and connectors mean fewer points of failure.

5. Streamlined Assembly

Fewer separate pieces to assemble = faster manufacturing and lower cost over time.

6. Design Freedom

Curves, folds, unusual angles? No problem.

When you combine these strengths, you get a PCB that’s not only dependable but also efficient in heat, space, and power.

Can rigid-flex aluminum substrate handle heat?

Yes. Thanks to the aluminum base layer, a rigid-flex aluminum substrate can dissipate heat much faster than standard FR4 PCBs. That makes it ideal for high-power LEDs, motor drivers, power converters, and even automotive ECUs that run hot under load.

Aluminum pulls heat away from sensitive components and spreads it across the board. This reduces thermal stress and extends the lifespan of the device.

What is a flexible aluminum PCB?

A flexible aluminum PCB might sound like a contradiction—but it exists. These boards use ultra-thin aluminum or aluminum-polymer composites to create circuits that bend slightly without breaking.

They don’t flex as much as pure polyimide-based flex PCBs, but they offer a middle ground. You get better heat handling than plastic-based flex boards and more flexibility than rigid aluminum PCBs.

They are perfect for wearables, automotive lighting strips, and foldable displays—places where space and heat must be controlled.

But when you need more complex bends, a rigid-flex aluminum substrate—with a true polyimide flex section—is still the better option.

What is the difference between rigid flex and flex with stiffener?

A flex PCB with stiffener uses an added material (like FR4 or stainless steel) to reinforce a flexible circuit. It’s a workaround to create rigid zones. But these are added separately and don’t become part of the electrical circuit.

A rigid-flex PCB, on the other hand, is built from the ground up to have both rigid and flex sections. The materials are laminated together and share common copper layers. The transition between flex and rigid is smooth, continuous, and far more robust.

Here’s a simple comparison:

Feature	Flex with Stiffener	Rigid-Flex PCB
Electrical Integration	Not shared	Shared between zones
Mechanical Strength	Moderate	Very strong
Size & Thickness	Bulkier	More compact
Cost Over Time	May increase due to failure	Higher upfront, lower long-term
Assembly Time	Longer	Faster and more integrated

So if your application requires reliability, space-saving, and superior performance, rigid-flex is your clear winner.

Where is rigid-flex aluminum substrate used?

Rigid-flex aluminum substrate PCB is widely used. Here’s where they make an impact:

1. Automotive Electronics

From advanced driver assistance systems (ADAS) to engine control units (ECUs), cars need compact, heat-resistant boards that perform under pressure.

2. LED Lighting Systems

LEDs generate heat—and need compact control circuits.

3. Wearable Technology

Smartwatches, fitness bands, and medical patches need bendable electronics that won’t break.

4. Industrial Equipment

Sensors, controls, and power systems in factories demand reliable boards that won’t fail under heat or vibration.

5. Medical Devices

Surgical tools, monitors, and implants need small, reliable PCBs.

6. Consumer Electronics

From foldable phones to compact drones, smart devices keep shrinking.

In short, any product that needs to be compact, tough, and thermally stable is a candidate for rigid-flex aluminum technology.

Conclusion:

Rigid-flex aluminum substrate combines the strength of rigid substrates with the flexibility of a bendable PCB. It offers better heat dissipation, space-saving structure, and high reliability for demanding applications. From automotive to LED lighting and wearable devices, it suits various environments where traditional PCBs fall short. It’s a solid choice for efficient, compact, and heat-resistant circuit solutions.

Want to design and produce rigid-flex aluminum substrates? Contact us now at sales@bestpcbs.com

Tags: Aluminum Flex-Rigid PCB, rigid flex pcb, rigid substrates, Rigid-flex aluminum substrate
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Rigid-flex PCB Design, Flex Rigid PCB Manufacturer

April 2nd, 2025

Flex rigid PCB manufacturer plays a crucial role in the electronics industry, providing innovative circuit board solutions that blend flexibility with rigidity. These advanced PCBs are widely used in aerospace, medical, automotive, and consumer electronics due to their durability and space-saving design. Understanding how they are made, their stackup structure, and the key factors in selecting a reliable manufacturer can help businesses make informed decisions. In this blog, we will explore everything from the manufacturing process to design considerations, ensuring you have all the details needed to choose the best supplier for your needs.

EBest Circuit (Best Technology) is a leading flex rigid PCB manufacturer with a direct factory in China. Our FPC factory was established in 2013. Rigid-flex PCB lead time in EBest Circuit (Best Technology) is 2~3 weeks. Rigid-flex PCB lead time in EBest Circuit (Best Technology) is 2~3 weeks. EBest Circuit (Best Technology) support PCBA. Customers provided components. If BOM is purchased by us, 1 week will be added for most cases. For components without stock, or with longer lead time, lead time will be negotiated with customers. If you have any questions or doubts about flex rigid PCB, just feel free to let us know at sales@bestpcbs.com at any time.

Rigid-flex PCB Design, Flex Rigid PCB Manufacturer

What is a Rigid-Flex PCB?

A rigid-flex PCB combines both rigid and flexible circuits into a single board. The rigid sections provide structural support, while the flexible parts allow for bending and movement. This design eliminates the need for connectors and cables, reducing weight and improving reliability. Many industries, including medical, aerospace, and consumer electronics, use these PCBs for compact and durable devices. By integrating flexible and rigid layers, they enhance mechanical performance and reduce assembly complexity.

What is the Standard Rigid-Flex PCB Stackup Used by Manufacturers?

A proper stackup is crucial for performance and durability. Manufacturers use multiple layers of flexible and rigid materials bonded together. A typical stackup consists of rigid FR4 sections, flexible polyimide layers, and adhesive or prepreg for bonding. The number of layers varies based on complexity, but maintaining a balanced stackup prevents warping. Some designs also incorporate shielding layers to reduce electromagnetic interference, ensuring signal integrity in high-speed applications.

How Are Rigid-Flex PCBs Made?

The rigid flex PCB manufacturing process involves several key steps:

Material Selection: Rigid FR4 and flexible polyimide materials are chosen based on application requirements.

Layer Stackup: The rigid and flex layers are arranged for optimal electrical performance and mechanical stability.

Drilling and Plating: Holes for vias and components are drilled and plated with copper.

Circuit Patterning: Photolithography and etching define circuit traces on both rigid and flexible sections.

Lamination: Rigid and flex layers are bonded using controlled heat and pressure.

Testing and Inspection: Electrical testing and reliability checks ensure performance and quality.

Precision at each step ensures the final product meets high-reliability standards, making it suitable for mission-critical applications.

What Are the Key Considerations in Flex Rigid PCB Design?

Designing a rigid-flex PCB requires careful planning to ensure functionality and durability. Key factors include:

Bend Radius: The flexible section should have a smooth curve to prevent stress fractures.

Via Placement: Vias should be placed in rigid areas to avoid mechanical strain in flex sections.

Trace Routing: Conductors should follow smooth curves rather than sharp angles for better signal integrity.

Material Selection: Choosing the right materials enhances flexibility, thermal stability, and performance.

Component Placement: Placing components strategically improves durability and assembly efficiency.

Proper rigid-flex PCB design practices prevent mechanical failures, enhance longevity, and improve overall PCB performance.

How Does a Reliable Flex Rigid PCB Manufacturer Ensure Quality?

A trusted flex rigid PCB manufacturer follows strict quality control measures. Here’s how they maintain high standards:

Advanced Equipment: Precision drilling, laser cutting, and automated inspection tools improve accuracy.

Material Testing: Verifying material properties ensures they meet electrical and mechanical requirements.

Process Control: Temperature, pressure, and humidity are monitored during manufacturing.

Reliability Testing: Flex cycling, thermal shock, and impedance tests confirm performance.

Industry Certifications: Compliance with ISO, IPC, and UL standards guarantees quality assurance.

Consistent quality control ensures each PCB performs optimally in demanding environments, reducing failures and increasing reliability.

How to Select the Best Flex Rigid PCB Manufacturer?

Choosing the right manufacturer affects product performance and reliability. Consider these factors:

Experience and Expertise: A manufacturer with years of experience understands complex designs.

Production Capability: Check their ability to handle multilayer and high-precision PCBs.

Quality Assurance: Look for certifications like ISO 9001 and IPC standards.

Customer Support: Responsive service ensures smooth project completion.

Global Supply Chain: Reliable logistics ensure timely delivery.

A well-established manufacturer guarantees high-quality production, helping businesses meet their technical requirements efficiently.

Why Choose EBest Circuit (Best Technology) as Your Flex Rigid PCB Manufacturer?

Precision Engineering: Utilizing state-of-the-art equipment, we deliver meticulous fabrication and assembly for highly complex non-standard flex rigid printed circuit boards like 16 layers rigid-flex circuit with impedance control. We offer integrated IC programming and in-house testing capabilities, ensuring end-to-end quality for even the most demanding technical requirements.

Strict Quality Control: Every board undergoes rigorous inspection and testing. In our flex rigid circuit board workshop, we have parallel exposure machines. And each production lot, each product will be checked strictly following IPC standards. And all of our products, Bech Technology are compliant with the latest ROHS.

Customized Solutions: We tailor designs based on customer specifications. If you have any unique technical and functional requirements, just feel free to let us know in advance, our R&D team and engineers is able to reply within 12 hours.

Fast and Reliable Delivery: Leveraging our extensive global supply chain network, we guarantee timely shipments and consistent on-time delivery. EBest Circuit (Best Technology) prioritizes efficiency through rapid turnaround processes, with our entire team committed to delivering orders within 2-3 weeks to meet customer needs seamlessly.

Working with EBest Circuit (Best Technology) means partnering with a manufacturer that prioritizes quality, innovation, and customer satisfaction.

In conclusion, finding the right flex rigid PCB manufacturer is essential for high-performance applications. Understanding the stackup, design considerations, and fabrication process helps in selecting the best supplier. EBest Circuit (Best Technology) stands out with its expertise, quality control, and customer support. Just feel free to contact us at sales@bestpcbs.com to get a quote for any rigid-flex PCB project!

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What is a rigid flex pcb? Rigid-flex PCB manufacturer

February 24th, 2025

Rigid-flex PCB is a circuit board that combines rigid board and flexible board. It has both the stability of rigid board and the bendability of flexible board. It is suitable for complex spatial layout and dynamic connection needs and is widely used in consumer electronics, automobile, medical, aerospace and other fields.

What is a rigid flex pcb? Rigid-flex PCB manufacturer

What is rigid flex PCBs?

Rigid-flex PCBs are an advanced type of printed circuit board that combines the best features of rigid and flexible PCBs into a single, seamless design. These boards consist of multiple layers of rigid and flexible substrates interconnected to create a durable, space-efficient, and highly reliable circuit solution.

Unlike traditional rigid PCBs, which are made of FR4 material, rigid-flex PCBs incorporate flexible layers that allow bending and folding without losing electrical functionality.

This hybrid design makes rigid-flex PCBs ideal for compact, high-performance electronic devices. They are widely used in aerospace, medical devices, military applications, consumer electronics, and industrial automation.

By eliminating the need for connectors and cables between rigid sections, these boards enhance reliability, reduce assembly complexity, and improve overall product performance.

What are the types of PCBs?

Printed circuit boards come in various types, each designed for specific applications. The most common types include rigid PCBs, flexible PCBs (FPCs), rigid-flex PCBs, single-layer PCBs, multilayer PCBs, and high-frequency PCBs.

Rigid PCBs are the most widely used type, featuring a solid, non-bendable structure made from fiberglass-reinforced epoxy (FR4). They provide mechanical stability and are commonly found in consumer electronics, automotive systems, and industrial equipment.

Flexible PCBs, in contrast, are made from polyimide or PET materials, allowing them to bend and twist to fit into tight spaces. They are commonly used in wearable devices, foldable smartphones, and medical sensors.

Rigid-flex PCBs combine both rigid and flexible elements, offering the benefits of both in a single board. They are particularly useful in applications where space is limited, and durability is crucial.

Other specialized types include metal-core PCBs for high-heat applications, ceramic PCBs for high-frequency circuits, and HDI PCBs for compact, high-density designs.

What are the advantages of rigid flex PCB?

Rigid-flex PCBs offer numerous advantages, making them the preferred choice for high-reliability applications. Their primary benefit is the ability to combine rigid and flexible circuits, reducing the need for additional connectors and wiring.

Another key advantage is space efficiency. Rigid-flex PCBs allow engineers to design compact, lightweight products without sacrificing performance.

By folding or bending the flexible sections, these boards can fit into complex enclosures, making them ideal for portable and miniaturized devices. Additionally, their reduced weight and material usage lower manufacturing and assembly costs.

Durability is another major strength. With fewer connectors and solder joints, rigid-flex PCBs are more resistant to mechanical stress, vibrations, and environmental factors. This makes them perfect for applications in aerospace, automotive, and military industries, where reliability is non-negotiable.

What are the disadvantages of rigid flex PCB?

While rigid-flex PCBs offer many advantages, they also come with some challenges. One of the main drawbacks is the higher manufacturing cost compared to standard rigid or flexible PCBs.

The complex design and fabrication process require specialized materials, and advanced equipment, leading to increased production expenses. However, this cost is often offset by the benefits of improved reliability and reduced assembly time.

Another challenge is the design complexity. Unlike standard PCBs, rigid-flex boards require precise layout planning, including bending radius calculations, flexible section reinforcement, and controlled impedance routing.

Manufacturing yield rates can also be lower due to the intricate layering and bonding processes involved. Any misalignment or material defects during production can impact the board’s functionality. To ensure high-quality results, working with an experienced rigid-flex PCB manufacturer is essential.

What is the difference between rigid-flex and semi-flex?

Rigid-flex and semi-flex PCBs serve different purposes. Rigid-flex PCBs are fully integrated designs with both rigid and flexible sections permanently bonded together. These boards can bend repeatedly without damage, making them suitable for applications requiring continuous movement or folding.

Semi-flex PCBs, on the other hand, are designed for limited bending. They are typically made from a partially flexible FR4 substrate that can bend a few times during installation but is not meant for continuous flexing.

Semi-flex boards are often used in products where a single bend is needed to fit the PCB into an enclosure, such as industrial control panels and certain automotive systems.

While both types improve space efficiency and reduce connectors, rigid-flex PCBs provide greater versatility for dynamic applications. Semi-flex PCBs offer a cost-effective alternative when only minimal bending is required.

What is the difference between FPC and rigid-Flex?

Flexible PCBs (FPCs) and rigid-flex PCBs share similarities but differ in their structural composition and usage.

FPCs are fully flexible circuits with no rigid sections, designed to bend and twist in any direction. They are commonly used in applications requiring extreme flexibility, such as foldable smartphones, medical sensors, and wearable devices.

Rigid-flex PCBs, in contrast, combine rigid and flexible layers. The rigid sections provide mechanical support for components, while the flexible sections allow for movement and space optimization. This hybrid approach is beneficial for complex assemblies where both strength and flexibility are needed, such as aerospace control systems and military-grade electronics.

When to use rigid-flex pcb?

Rigid-flex PCBs are ideal for applications where space constraints, reliability, and durability are critical. They are commonly used in aerospace and defense electronics, where weight reduction and high reliability are essential.

Medical devices, such as pacemakers and imaging equipment, also benefit from rigid-flex PCBs due to their compact size and long-term reliability.

Consumer electronics, including foldable smartphones, smartwatches, and VR headsets, leverage rigid-flex PCBs to create lightweight, compact designs.

Additionally, automotive applications use them in advanced driver-assistance systems (ADAS) and infotainment systems to ensure consistent performance under extreme conditions.

Industries that require rugged, high-performance electronics can greatly benefit from rigid-flex PCB technology. The ability to withstand harsh environments, reduce assembly complexity, and enhance product longevity makes them a smart choice for advanced electronic designs.

What is an example of a rigid-flex PCB?

One of the best examples of rigid-flex PCB applications is in foldable smartphones. These devices require flexible circuits to accommodate screen folding while maintaining uninterrupted electrical connections. The integration of rigid and flexible sections enables compact, lightweight designs without sacrificing durability.

Another example is in aerospace control panels. Rigid-flex PCBs help reduce wiring complexity in cockpit instruments, ensuring high reliability in extreme environments.

Similarly, medical implants like pacemakers use rigid-flex PCBs to achieve a compact form factor while maintaining long-term reliability inside the human body.

Military-grade electronics, such as communication devices and guidance systems, also rely on rigid-flex PCBs. Their ability to withstand vibrations, temperature fluctuations, and high mechanical stress makes them a preferred choice for mission-critical applications.

Conclusion：

Rigid-flex PCBs offer a powerful combination of flexibility, durability, and space efficiency. They eliminate the need for connectors, reduce wiring complexity, and improve reliability, making them ideal for high-performance applications.

For high-quality rigid-flex PCB manufacturing, EBest Circuit (Best Technology) offers expert solutions tailored to your needs. Contact us at sales@bestpcbs.com to discuss your project.

Tags: rigid flex pcb, rigid flex pcb design, Rigid-flex PCB
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Non-Flex Cut vs Flex Cut PCB: What Is Flex Cut PCB?

February 18th, 2025

The debate of non-flex cut vs flex cut PCB has been a common topic for engineers and manufacturers. When designing printed circuit boards (PCBs), one key decision is whether to use a flex cut or non-flex cut PCB. These two types of PCBs serve different purposes, with unique advantages depending on the application. But how do they differ, and when should you use each? This guide will dive into the specifics, providing you with insights to make an informed decision.

What is a Flex Cut PCB?

A flex cut PCB is a type of printed circuit board that’s designed to be flexible. Unlike traditional rigid PCBs, flex PCBs can bend and flex without compromising the performance of the electrical circuits. This flexibility is achieved by using materials such as polyimide, which allows the board to conform to various shapes and spaces.

Flex cut PCBs are commonly used in devices where space is limited or for designs that require a dynamic or compact setup, such as in wearable tech or mobile phones. Their flexible nature provides the freedom to design intricate layouts without being restricted by rigid geometries.

What is the Difference Between Flex Cut and Non-Flex Cut PCB?

The main difference between flex cut and non-flex cut PCBs lies in their physical structure and flexibility. As mentioned, flex cut PCBs are made from flexible materials, which means they can be bent, twisted, or folded. This flexibility makes them suitable for applications where space constraints are a concern, and the board needs to fit into non-traditional forms or be more compact.

In contrast, non-flex cut PCBs, often referred to as rigid PCBs, are built using rigid substrates like FR4 or aluminum, providing stability and durability. These boards do not bend and are generally used in devices that do not require flexibility.

Both types of PCBs have their unique advantages. Flex cut PCBs are best for space-saving and adaptability, while non-flex cut PCBs are ideal for products that need more stability and rigidity.

Why Use a Flex PCB?

There are several reasons to opt for a flex PCB in certain applications. One of the biggest advantages is its ability to save space. Flex PCBs can be folded or shaped to fit into areas where rigid PCBs cannot. This makes them an excellent choice for compact electronic devices such as smartphones, cameras, and medical equipment.

Additionally, the flexibility allows for more robust designs in environments with high mechanical stress, such as robotics or wearables. Flex PCBs can withstand vibration and movement better than rigid boards, offering better durability in these conditions.

Finally, the lightweight nature of flex PCBs contributes to the overall efficiency of the product, making them an essential component in modern, miniaturized electronics.

What is an FR4 Plate?

FR4 is a widely used material in the manufacturing of rigid PCBs. It stands for “Flame Retardant 4” and is a type of fiberglass epoxy laminate. The FR4 material provides excellent strength, low moisture absorption, and good electrical insulation properties.

While FR4 is typically used for non-flex cut PCBs, it can also be used in multi-layer flexible PCBs in certain designs. Its role is to provide stability and electrical insulation, making it a crucial material in traditional PCBs.

What is Tri-Mode Non-Flex Cut Hotswap PCB?

Tri-mode non-flex cut hotswap PCBs are a specialized type of PCB designed for mechanical keyboards, offering a flexible, user-friendly experience. The term “tri-mode” refers to the ability to support multiple connection types, such as wired, Bluetooth, and wireless.

The non-flex cut hotswap design enables users to easily replace or swap out switches on the keyboard without the need for soldering. This makes it ideal for enthusiasts who want to customize their keyboards with different types of switches. It combines the advantages of non-flex cut rigidity with the versatility of hotswapping.

What is a Rigid-Flex PCB?

A rigid-flex PCB is a hybrid of both rigid and flexible PCB technologies. It consists of both rigid and flexible sections integrated into a single board. These PCBs offer the best of both worlds, combining the stability and reliability of rigid PCBs with the flexibility of flex PCBs.

Rigid-flex PCBs are often used in high-performance applications such as aerospace, medical devices, and automotive systems. They provide a compact solution where multiple PCB types need to coexist, and their flexible sections can be bent or folded to fit complex spaces.

What Are the Disadvantages of Rigid-Flex PCBs?

Despite their advantages, rigid-flex PCBs come with some drawbacks. One major disadvantage is their cost. Due to the complexity of manufacturing, rigid-flex PCBs tend to be more expensive than traditional rigid or flex PCBs.

Additionally, the design and production process for rigid-flex PCBs is more intricate, requiring higher precision and more time. This can also lead to longer lead times for production, which may not always be ideal for projects with tight deadlines.

When Should I Use a Flex PCB?

Flex PCBs are perfect for applications where flexibility, compact design, and space-saving are important. You should use a flex PCB when your product needs to fit into tight or unique spaces, like wearable devices, medical equipment, or consumer electronics.

They are also a good choice for products that need to endure repetitive movement or vibrations. In situations where the PCB needs to be bent or folded without breaking, such as in robotics or automotive designs, flex PCBs offer exceptional reliability.

Are Flexible PCBs More Expensive?

Flexible PCBs generally come at a higher cost compared to non-flex cut PCBs. This is due to the specialized materials and the intricate manufacturing process required for flexible designs.

However, despite the initial cost increase, flex PCBs can provide long-term cost savings by reducing the overall size of the device and minimizing the need for additional components or connectors. For applications where space is crucial or where traditional PCB designs would be too bulky, the investment in a flex PCB can pay off in the long run.

In the debate of non-flex cut vs flex cut PCB, the right choice ultimately depends on the needs of your project. Flex PCBs excel in compactness and flexibility, making them a great choice for dynamic, space-constrained designs. On the other hand, non-flex cut PCBs offer superior stability and durability for applications where rigidity is key.

For some projects, you might even find that combining the benefits of both technologies, like in rigid-flex PCBs, offers the perfect balance of performance and flexibility. When making your decision, consider the design requirements, budget, and long-term needs of your application.

By understanding the differences between flex and non-flex cut PCBs, you can make the best choice for your next project, ensuring efficiency, durability, and performance. Best Technology sets itself apart by providing top-notch, customized Non-Flex Cut and Flex Cut PCB products, quick delivery, and superior customer care. Contact us at sales@bestpcbs.com for inquiries or further details.

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What material is used for flexible PCB?

October 24th, 2024

Flexible PCB is a printed circuit board made of flexible substrate, which can be bent, folded or twisted to a certain extent to meet the needs of various complex electronic device structures.

What are flexible PCBs made of?

Flexible PCBs are mainly made of polyimide or polyester film. These materials have good flexibility and insulation properties, which enable flexible PCBs to maintain stable working conditions in various bending and twisting environments.

The manufacturing process of flexible PCBs includes the following main steps:

Design phase: Use design software to create a prototype of the circuit board, determine the required lines, circuits and components, and design the shape and size of the flexible PCB according to the shape and size of the product.

Board making phase: Print the required lines and patterns on the plastic substrate, usually using photolithography techniques such as coating photolithography and inkjet printing.

Surface treatment and coating: Clean the circuit board and apply a protective coating to prevent chemical and mechanical wear, moisture, corrosion, etc.

Electroplating copper: Apply electroplating copper to certain parts of the flexible PCB to thicken the line.

Pattern chemical etching: Etch away the unnecessary parts of the circuit board and retain the required lines and components.

Molding and perforation: Cut the flexible PCB into the desired shape.

What is the difference between FR4 and flex PCB?

Material composition and performance

FR4: FR4 is the most common PCB substrate, mainly composed of glass fiber and epoxy resin. It has good electrical, thermal and mechanical properties.

Flexible PCB: Flexible PCB (FPC) is mainly made of materials such as polyimide (PI) and is flexible and bendable. They are often used in application scenarios that require frequent bending or limited space.

Application scenarios

FR4: Due to its rigidity and stability, FR4 is often used in applications that require high mechanical strength and stability, such as computer motherboards, mobile phone motherboards, etc.

Flexible PCB: Flexible PCB is often used in applications in car curves and corners, display screens and reverse cam screens, etc. due to its flexibility and bendability.

Manufacturing process and cost

FR4: The manufacturing process includes drilling, etching, copper plating, etc., with moderate cost, suitable for most consumer electronic products.

Flexible PCB: The manufacturing process is relatively complex and the cost is high, but it can meet the needs of specific applications.

In summary, FR4 and flexible PCBs have significant differences in material composition, performance and application scenarios. Choosing the right material depends on the specific application requirements.

What is the difference between a rigid PCB and a flexible PCB?

The main differences between rigid PCBs and flexible PCBs include softness, load-bearing capacity, durability, heat resistance and other aspects.

Softness: Flexible PCBs (FPCs) have good flexibility and can be easily twisted, bent and even folded, and are suitable for application scenarios that require flexible wiring. Rigid PCBs, on the other hand, are harder and cannot be bent, and are usually used in devices that require stability and high load capacity.

Load-bearing capacity: Flexible PCBs have relatively weak current carrying capacity and are suitable for applications with smaller currents. Rigid PCBs have stronger current carrying capacity and are suitable for high-load electronic devices.

Durability and heat resistance: Flexible PCBs can better absorb vibration and shock, have high durability and heat resistance, and can be used in extreme environments. Although rigid PCBs are thicker, they are easily damaged under the influence of high temperatures and chemicals.

Manufacturing process and materials: Flexible PCBs use flexible materials such as polyimide, and a cover layer process is used during the manufacturing process to protect the circuit. Rigid PCBs use thicker materials, usually made of glass-like materials, and require reinforcement.

Application scenarios: Flexible PCBs are widely used in modern smart devices such as smartphones, tablets, and wearable devices due to their flexibility and thinness. Rigid PCBs are often used in devices that require stability and high load capacity, such as laptops and desktop computers.

In summary, there are significant differences between rigid PCBs and flexible PCBs in terms of softness, load-bearing capacity, durability, heat resistance, and application scenarios. The selection of the appropriate type of circuit board should be determined according to specific application requirements.

What is the advantage of flex PCB?

Flexible PCB (Flexible Printed Circuit, FPC for short) has the following main advantages:

Flexibility: The main advantage of flexible PCBs is their elasticity and bending ability. They can be easily twisted, bent, and even folded, suitable for design requirements of various complex shapes.

Reduce weight and space: Flexible PCBs not only provide greater design freedom, but also have better space utilization and weight efficiency. Due to their thin and light characteristics, flexible PCBs can greatly reduce weight and space, especially for small devices.

Suitable for harsh environments: Flexible PCBs can be made of various corrosion-resistant materials and can withstand harsh environmental conditions.

Better thermal management: Flexible PCBs are made of polyimide, which has excellent thermal stability and can withstand extremely high heat.

Reduce costs: Flexible PCBs reduce assembly costs by reducing space requirements and the number of components. Since the need for wiring and connectors is reduced, testing and rework time is also reduced, improving productivity and efficiency.

In summary, flexible PCBs have significant advantages in flexibility, weight, space utilization, environmental adaptability and cost-effectiveness, making them an ideal choice for many high-tech products and applications requiring high reliability.

What are the disadvantages of flexible PCB?

The main disadvantages of flexible PCBs (FPCs) include:

High one-time initial cost: Since flexible PCBs are designed and manufactured for special applications, the cost of circuit design, wiring and photographic plates is high.

Difficult to change and repair: Once a flexible PCB is made, changes must start from the base map or the compiled photolithography program, so it is not easy to change. Its surface is covered with a protective film, which needs to be removed before repair and restored after repair, which is a relatively difficult task.

Size is limited: Flexible PCB is usually manufactured by intermittent process when it is not yet popular. Therefore, it is limited by the size of production equipment and cannot be made very long or wide.

Improper operation can easily cause damage: Improper operation by the assembly personnel can easily cause damage to the flexible circuit. Its soldering and rework require trained personnel to operate.

How thick is a flex PCB board?

The common thickness of flexible PCB board is 0.2mm. The thickening layer will be added behind the parts to be soldered. The thickness of the thickening layer is generally 0.2mm or 0.4mm12.

In addition, the thickness of flexible PCB board usually ranges from 0.1mm to 0.4mm, of which the thickness of 0.1mm to 0.4mm is called ultra-thin PCB board.

Where are flexible PCBs used?

Flexible PCB (Flexible Printed Circuit Board, FPC) is widely used in many fields, mainly including the following aspects:

Consumer electronics: Flexible PCB is widely used in consumer electronics such as smartphones, tablets, smart watches, etc.

Medical equipment: In medical equipment, flexible PCB can bend and adapt to specific shapes, and is often used in electrocardiographs, blood pressure monitors, monitoring equipment and medical sensors, etc.

Automotive electronics: Flexible PCB plays an important role in automotive electronic systems, connecting in-vehicle entertainment systems, navigation systems, dashboards, body control modules and safety systems, etc.

Aerospace: Flexible PCB is also widely used in the aerospace field, such as satellite communications, spacecraft control, etc.

Industrial control and automation: In the field of industrial control and automation, flexible PCB is used to connect sensors, actuators, control modules and data acquisition equipment, etc.

LED lighting: Flexible PCB is also used in LED lighting products to provide connection and signal transmission functions.

In summary, the material combination of flexible PCBs gives them unique properties and a wide range of application prospects. The flexible substrate provides bendability and durability, the conductive layer ensures efficient transmission of electronic signals, and the cover layer provides protection for the entire structure. The continuous innovation and optimization of these materials will continue to promote the development of flexible PCBs.

Tags: flex PCB, flexible PCB, PCB
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