Archive for the ‘PCB Technology’ Category

What You Know About Counterbores in PCB Design and Manufacturing

Friday, August 18th, 2023

In the world of design and manufacturing, precision is paramount. Every detail, down to the placement of a single component, can impact the performance and appearance of a product. This is where the concept of counterbores comes into play, a technique employed in various industries to create recessed areas for components or fasteners.

But firstly, what is counterbore?  Today we will show you the definition and applications of the countersink in a PCB design. 

Definition and Applications:

A counterbore is a cylindrical, flat-bottomed hole that is strategically cut into a material to accommodate specific components or fasteners. It is commonly used in various industries, including woodworking, metalworking, and mechanical engineering. The purpose of a counterbore is to create a recessed area where a component, such as a bolt head, nut, or other hardware, can sit flush with or below the surface of the material. This technique ensures a smooth appearance, prevents interference with other components, and provides mechanical stability.

Counterbores in PCB Design and Manufacturing

In the realm of printed circuit boards (PCBs), counterbores play a crucial role in achieving efficient and functional designs. PCBs are essential components in electronic devices, and their design requires careful consideration of component placement, connectivity, and mechanical stability. Counterbores in PCBs serve several important functions:

  1. Component Alignment and Clearance:  Certain components on a PCB, such as connectors, switches, or specialized modules, require precise alignment and clearance for optimal functionality. A counterbore can be introduced to create a recessed area that accommodates these components, ensuring proper alignment with neighboring components and minimizing the risk of interference.
  • Flush Mounting: To maintain a sleek and compact design, some components need to be mounted flush with the surface of the PCB. A counterbore creates a flat-bottomed recess that allows the component to sit at the same level as the PCB surface, contributing to an aesthetically pleasing and functional layout.
  • Mechanical Support: Components that are susceptible to mechanical stress or impact may benefit from additional support. By incorporating a counterbore, the PCB design can provide a more secure location for these components, reducing the risk of damage.
  • Heat Dissipation Enhancement: In applications where certain components generate significant heat, such as power amplifiers or processors, heat sinks are often employed to dissipate the heat. A counterbore can facilitate proper alignment and contact between the heat sink and the component, optimizing heat transfer and overall thermal performance.

The production of counterbores in PCBs involves specialized manufacturing techniques. BEST Technology as a professional PCB manufacturer, we will use precision drilling and routing equipment to create accurately sized and positioned counterbores.

If you want to know more about the counterbores, welcome to follow our post or contact us.

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Enhancing UV LED Performance with MCPCB: Advantages and Innovative Applications

Thursday, August 10th, 2023

In the field of ultraviolet light-emitting diodes (UV LED), the integration of Metal Core Printed Circuit Boards (MCPCB) plays a significant role in improving UV LED performance, thermal management, and overall reliability. In this blog post, we will explore the importance of MCPCB in UV LED applications, highlighting its advantages with concrete data to demonstrate its practicality.

  1. Efficient Heat Dissipation:

MCPCBs excel in efficient heat dissipation, ensuring optimal UV LED performance and longevity. With a metal core typically made of aluminum or copper, MCPCBs possess high thermal conductivity. For instance, MCPCBs have a thermal conductivity coefficient of normally 1.0-3.0 W/mK, it needs to be customized if the thermal conductivity exceeds 3.0W/mk. this exceptional thermal conductivity allows for rapid dissipation of generated heat, preventing heat accumulation and ensuring UV LEDs operate within their optimal temperature range.

2. Enhanced Thermal Conductivity:

MCPCBs contribute to effective heat dissipation through improved thermal conductivity. Studies indicate that MCPCBs can enhance thermal conductivity up to ten times higher than standard FR4 PCBs. Because the stack up of MCPCB is different with PCB, please see below stack up. This enhanced thermal conductivity aids in achieving a uniform temperature distribution across the entire MCPCB, reducing the risks of hotspots and thermal stress on UV LEDs. Consequently, UV LEDs can maintain their performance and reliability even during extended operation.

1ozCopper layer
1.5mm without copperCore base

3. Reliability in Harsh Environments:

MCPCBs are designed to withstand harsh environments, ensuring reliability in UV LED applications. The metal core of MCPCBs provides higher mechanical strength and resistance to thermal stress. For example, the coefficient of thermal expansion (CTE) of an MCPCB can be matched with UV LEDs, minimizing the risk of mechanical failures caused by thermal mismatch. These features enable MCPCBs to operate reliably even in high-temperature environments or under exposure to ultraviolet radiation, thereby extending the lifespan of UV LED devices.

4. Electrical Isolation:

MCPCBs offer electrical isolation between the metal core and circuit layers, ensuring safe and reliable operation of UV LEDs. The dielectric layer, typically made of materials such as epoxy resin or thermally conductive dielectric (TCF), exhibits high breakdown voltage and insulation resistance. This electrical isolation minimizes the risk of short circuits or electrical interference, protecting UV LEDs and the entire system from potential damage.

5. Performance Optimization:

By incorporating MCPCBs into UV LED technology, manufacturers can optimize the performance of their UV LED devices. The improved heat dissipation and thermal conductivity of MCPCBs enable UV LEDs to operate at maximum efficiency. Research shows that using MCPCBs can reduce LED junction temperatures by up to 20-30°C, improving light output and enhancing overall performance. This optimal performance ensures consistent UV light generation, making MCPCBs an ideal choice for various UV LED applications, including curing, sterilization, and phototherapy.


The use of MCPCBs in UV LED technology offers practical benefits in heat dissipation, thermal conductivity, reliability, and electrical isolation. Concrete data and research support the effectiveness of MCPCBs in efficient heat management, even in harsh environments, enabling reliable operation of UV LEDs. With enhanced performance provided by MCPCBs, UV LED systems can deliver consistent, efficient, and durable UV light output, expanding the possibilities of UV applications in various industries. The utilization of MCPCBs further solidifies their critical role as a key supporting technology in the UV LED field.

If you are designing a metal core PCB and seeking for a reliable manufacturer, welcome to leave you message or contact us directly.

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Do You Know What Is HDI Board?

Thursday, August 10th, 2023

HDI boards are a type of printed circuit board (PCB) technology that enables higher circuit density and smaller form factors compared to traditional PCBs. HDI boards are commonly used in applications where space is limited, such as mobile devices, wearables, and aerospace systems.

Best Technology has rich experience in HDI rigid flex pcb manufacturing, below is one of our 7 layers HDI rigid flex pcb.

In Best Technology, our HDI board usually has the blind holes or buried holes, and the minimum hole size usually is 0.1mm. This board has the blind and buried holes, and the minimum hole size is 0.1mm. 100 ohm differential impedance control with 50 single ended impedance control. It’s surface finish is ENIG, 1oz copper for outer layers, 1/2oz copper for inner layers, green solder mask with white silkscreen. total thickness is 1.4mm.

Here are some key features and aspects of HDI boards:

  1. High Density: HDI boards are designed to accommodate a large number of densely packed components and interconnections. They typically have multiple layers with high routing density, allowing for more complex circuitry in a smaller footprint.
  • Microvias: HDI boards extensively use microvias, which are very small holes drilled into the board to create electrical connections between different layers. Microvias are smaller in size compared to traditional vias, allowing for increased routing density.
  • Staggered and Stacked Microvias: HDI boards employ different types of microvias, including staggered and stacked microvias. Staggered microvias connect adjacent layers, while stacked microvias connect non-adjacent layers, providing even higher routing density.

Blind and Buried Vias: HDI boards often utilize blind and buried vias, which are vias that do not extend through the entire board. Blind vias connect an outer layer with one or more inner layers, while buried vias connect inner layers only. These vias help optimize space and increase routing capabilities.

  • Fine Pitch Components: HDI boards support the use of fine pitch components, such as microcontrollers, ball grid array (BGA) packages, and small surface-mount devices (SMDs). The high routing density and smaller features of HDI boards make them suitable for accommodating these tiny components.
  • Increased Signal Integrity: HDI boards can provide improved signal integrity due to shorter trace lengths and reduced noise interference. The compact design minimizes signal loss and impedance mismatches, allowing for better performance in high-frequency applications.
  • Design Considerations: Designing HDI boards requires expertise in factors such as layer stacking, via types, trace widths, and clearances. Advanced design software and manufacturing techniques are often employed to ensure precise alignment and reliability of the intricate interconnections.
  • Manufacturing Challenges: HDI boards can be more challenging to manufacture compared to standard PCBs. The use of smaller features and complex layer structures requires specialized fabrication techniques, such as laser drilling, sequential lamination, and precise registration control.

HDI technology has become increasingly prevalent in the electronics industry, enabling the development of smaller, lighter, and more sophisticated devices. It offers enhanced electrical performance, improved reliability, and greater design flexibility. If you have any comments about the HDI board, please feel free to contact Best Technology Team e-mail:

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Heavy Copper PCB for Industrial Power Supply

Saturday, July 29th, 2023

All of us know the printed circuit board, but do you know what is the heavy copper PCB? Best Tech is a very experienced heavy copper PCB fabricator since year 2006. Heavy Copper PCB is a type of printed circuit board that features with thicker copper layers than standard FR4 PCBs. While conventional PCBs typically have copper thicknesses ranging from 1 to 3 ounces (per square foot), heavy copper PCBs have copper thicknesses exceeding 3 ounces and can go up to 20 or more ounces. These copper layers are typically found in the inner and outer layers of the PCB, heavy copper providing enhanced current-carrying capacity and improved heat dissipation capabilities.

The increased copper thickness in heavy copper PCBs allows them to handle higher currents without experiencing excessive heat buildup or voltage drops. This makes them well-suited for applications that require high power handling, such as industrial power supplies, power converters, motor drives, and automotive electronics. Heavy copper PCBs are designed to withstand harsh operating conditions and provide robust performance and reliability.

Today, we would like to talk about the heavy copper PCB used in Industrial Power Supply. In this blog post, we will explore the realm of Industrial Power Supply, delving into the design considerations, material selection, production challenges, exceptional heat dissipation, and unrivaled conductivity of Heavy Copper PCBs. Join us on this enthralling journey as we uncover the secrets behind their application in Industrial Power Supply scenarios, including the testing of inductance, capacitance, and resistance. Get ready to witness the power of Heavy Copper PCBs in the realm of Industrial Power Supply!

Firstly, before you are moving start for the design, it need to get to understand the Design guideline rules of heavy copper PCB.

From the guidelines of heavy copper PCB, it could get to know it encompass considerations such as trace width, trace spacing, and thermal relief patterns. The increased copper thickness necessitates wider traces to accommodate higher currents, while proper spacing is crucial to avoid thermal hotspots and ensure reliable operation. Additionally, selecting suitable materials with excellent mechanical strength and thermal properties is vital to ensure the robustness and longevity of Heavy Copper PCBs. Hope this will bring some ideas to you during your design.

Secondly, as a heavy cooper PCB manufacturing vendor, Best Tech would like to advise the Production Challenges for the heavy copper PCB.

During producing Heavy Copper PCBs presents manufacturers with a set of intricate challenges. Achieving uniform copper thickness across the board’s surface demands advanced plating techniques and precise control over process parameters. Careful attention must be given to the etching process to prevent over-etching, which can compromise the integrity of the copper layers. Moreover, the additional weight of copper requires a sturdy substrate to support the board’s structure. Manufacturers must navigate these challenges with expertise and precision to deliver high-quality Heavy Copper PCBs.

You may have a question in mind, why we need to use the heavy copper PCB for the Industrial Power Supply, because the heavy copper PCB have Exceptional Heat Dissipation and Conductivity: One of the standout features of Heavy Copper PCBs is their unrivaled heat dissipation capabilities. The increased copper thickness acts as a robust conductor, efficiently channeling heat away from power components. This exceptional heat dissipation prevents thermal stress and ensures the longevity and reliability of Industrial Power Supply systems. Additionally, the high conductivity of Heavy Copper PCBs enables efficient power transmission, reducing losses and improving overall system efficiency.

Furthermore, Heavy Copper PCBs undergo rigorous testing to ensure optimal performance in Industrial Power Supply applications. Inductance testing verifies the effectiveness of copper layers in reducing magnetic interference. Capacitance testing evaluates the ability of the PCB to store electrical energy, while resistance testing determines the conductivity and resistance of copper traces. These tests play a crucial role in validating the quality and performance of Heavy Copper PCBs in demanding power supply scenarios.

Heavy Copper PCBs find widespread applications in the field of Industrial Power Supply, particularly in the production of robust and efficient power control products. They are integral components in industrial power converters, motor drives, uninterruptible power supplies (UPS), and various automation systems. The exceptional heat dissipation and high current-carrying capacity of Heavy Copper PCBs make them ideal for handling the power demands of these applications, ensuring reliable and efficient power delivery.

Finally, in the world of Industrial Power Supply, Heavy Copper PCBs emerge as true powerhouses, combining meticulous design, advanced manufacturing processes, and exceptional heat dissipation capabilities. By adhering to design guidelines, overcoming production challenges, and conducting thorough testing, Heavy Copper PCBs prove their mettle in demanding power supply scenarios. As they continue to evolve, these powerhouses will shape the future of Industrial Power Supply, empowering systems with reliability, efficiency, and unrivaled performance. Prepare to witness the electrifying impact of Heavy Copper PCBs in the realm of Industrial Power Supply!

If you have more question heavy copper PCB for Industrial Power Supply, warmly welcomed to contact Best Tech for more get more information of heavy copper PCB which used in Industrial Power Supply. You can visit to know more about us.

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5 Tips Tell You How to Solder BGA Better in PCBA

Monday, May 29th, 2023

BGA (Ball Grid Array) soldering is a widely used method in the electronics manufacturing industry for mounting integrated circuits onto printed circuit boards (PCBs). This method provides a more compact and reliable connection compared to traditional through-hole or surface mount technology (SMT). However, the complexity of BGA soldering poses various obstacles during the manufacturing process. Herein, we will explore the challenges faced in BGA soldering and discuss effective strategies to address them.

What is BGA Soldering?

BGA soldering is a technique that involves the attachment of integrated circuit packages to a PCB using an array of solder balls. These solder balls are typically made of lead-based or lead-free alloys, depending on environmental regulations and specific requirements. The BGA package consists of a substrate, which acts as a carrier for the integrated circuit, and the solder balls that form the electrical and mechanical connections between the package and the PCB.


The Importance of BGA Soldering in Electronics Manufacturing

BGA soldering plays a critical role in the manufacturing of various electronic devices such as computers, smartphones, and gaming consoles. The increased demand for smaller and more powerful electronics has driven the adoption of BGA packages. Their compact size and high pin density make them suitable for advanced applications where space is limited.

Challenges Faced in BGA Soldering

  • Component Alignment and Placement

One of the primary challenges in BGA soldering is ensuring accurate component alignment and placement on the PCB. The small size of the solder balls and the dense layout of the BGA package make it difficult to achieve precise positioning. Misalignment during the assembly process can result in solder bridges, open connections, or mechanical stress on the package.

To address this challenge, manufacturers employ advanced technologies such as Automated Optical Inspection (AOI) and X-ray Inspection. AOI systems use cameras and image processing algorithms to verify the correct alignment and placement of BGA components. X-ray inspection, on the other hand, allows manufacturers to see beneath the surface of the PCB and detect any misalignment or defects that may not be visible to the naked eye.

  • Solder Paste Application

Another significant challenge in BGA soldering is achieving precise and consistent solder paste application. Solder paste, a mixture of solder alloy and flux, is applied to the PCB pads before placing the BGA package. Inadequate or excessive solder paste can lead to solder defects such as insufficient solder joints, solder voids, or solder bridging.

To overcome this challenge, careful attention must be given to stencil design and aperture selection. Stencils with appropriate thickness and properly sized apertures ensure accurate solder paste deposition. Additionally, manufacturers can employ Solder Paste Inspection (SPI) systems to verify the quality and consistency of the solder paste applied. The solder paste that Best Technology uses is SAC305 solder paste, which has good printability and excellent stability.

  • Temperature Profiling

Temperature profiling, or we can say the thermal management, it is crucial in BGA soldering to ensure proper reflow of the solder paste. The reflow process involves subjecting the PCB to a carefully controlled temperature profile, allowing the solder paste to melt, form a reliable joint, and solidify. Inadequate temperature profiling can lead to insufficient solder wetting, incomplete reflow, or thermal damage to components.

Manufacturers must optimize the reflow oven setup and calibration to achieve the correct temperature profile. Thermal profiling techniques, such as the use of thermocouples and data loggers, help monitor and control the temperature during the reflow process.

  • Reflow Process

The reflow process itself presents challenges in BGA soldering. The soak zone, ramp rates, and peak temperature must be carefully controlled to prevent thermal stress on the components and ensure proper solder reflow. Inadequate temperature control or improper ramp rates can result in solder defects such as tombstoning, component warpage, or voids in the solder joints.

Manufacturers need to consider the specific requirements of the BGA package and follow recommended reflow profiles provided by component suppliers. Proper cooling after reflow is also essential to prevent thermal shock and ensure the stability of the solder joints.

  • Inspection and Quality Control

Inspection and quality control are critical aspects of BGA soldering to ensure the reliability and performance of the solder joints. Automated Optical Inspection (AOI) systems and X-ray inspection are commonly used to detect defects such as misalignment, insufficient solder wetting, solder bridging, or voids in the solder joints.


In addition to visual inspection techniques, some manufacturers may perform cross-section analysis, where a sample solder joint is cut and examined under a microscope. This analysis provides valuable information about the quality of the solder joint, such as solder wetting, void formation, or the presence of intermetallic compounds.

In a word, BGA soldering presents unique challenges in electronics manufacturing, primarily related to various factors. By addressing these challenges effectively, manufacturers can ensure the reliability and performance of BGA solder joints, contributing to the production of high-quality electronic devices. Best Technology has rich experience in PCBA assembly and we mounted thousands PCBs for our customers, whatever it is simple design or complex design, all the products are assemble perfect and work well in customer side. Please feel free to contact us for any questions about PCBA.

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Key Challenges in Solder Mask Printing for Heavy Copper PCBs

Tuesday, May 23rd, 2023

As the demand for higher power and miniaturization of electronics increases, so does the need for Heavy Copper Printed Circuit Boards (PCBs). From our last blog – Why choose Heavy Copper PCB for your High Current Project, we know the heavy copper PCBs are defined as those with copper thicknesses greater than 3 oz. These PCBs are designed to withstand high current and thermal loads, making them suitable for power electronics applications. However, the increased copper thickness also poses challenges during the solder mask printing process.


Understanding solder mask

Solder mask (short for S/M in the industry) is a protective coating applied to PCBs to prevent solder bridges and improve solder joint quality. The solder mask is coated to the PCB surface using a screen-printing process, where the desired pattern is created using a stencil and the solder mask ink is then deposited onto the PCB. The ink is then cured, either through heat baking or UV light, to form a solid coating.

There are several types of solder mask materials available, including epoxy, acrylic, and liquid photo imageable (LPI) solder mask. Each type has its advantages and disadvantages, depending on the application requirements.

The benefits of using solder mask in PCB manufacturing include increased reliability, improved solderability, and reduced risk of short circuits and corrosion. The solder mask we usually use is Taiyo, which has high reliability and excellent heat resistance.


Challenges in solder mask printing of heavy copper PCBs

While solder mask printing is a critical step in PCB manufacturing, the increased copper thickness in heavy copper PCBs presents several challenges for printing process as I mentioned before. It’s difficult to apply enough solder mask to cover thick copper pattern and base material with severe height difference.

1. The high copper thickness and thermal conductivity of heavy copper PCBs make it difficult for the solder mask ink to adhere properly to the surface. This can result in insufficient coverage and registration accuracy, which can affect the overall quality and reliability of the PCB.

2. The high copper thickness can cause stress on the solder mask, leading to mask cracking and peeling. The navigation mark on the substrate has specific ink thickness requirements due to limitations in the ink thickness that can be applied to the substrate. If the ink thickness on the substrate is too thick, it may result in solder resist cracks in the substrate position after the printed circuit board is soldered. This can occur during reflow soldering or thermal cycling, resulting in poor solder joint quality and reduced reliability.

3. The thick solder mask is also more difficult to exposure and develop. If the exposure energy is too weak or not enough, then some undercut problem may happen.

How to overcome this challenge?

To address these challenges, it is essential to choose the right solder mask materials and optimize the application process.

  • Choosing the right solder mask materials is crucial for ensuring proper adhesion and coverage on heavy copper PCBs. LPI solder mask is often preferred for heavy copper PCBs due to its excellent adhesion and thermal stability. However, epoxy and acrylic solder mask materials can also be used with proper surface preparation.
  • Optimizing the solder mask application process can also help address the challenges of heavy copper PCBs. This can include using a thinner stencil for improved registration accuracy and applying multiple coats of solder mask for better coverage. Advanced solder mask technology, such as laser direct imaging (LDI), can also help improve registration accuracy and reduce the risk of mask cracking and peeling.
  • Optimizing the printing process, now in Best Technology, we always make the substrate first, fill the substrate with the solder mask and then treat it as a normal PCB for normal printing solder mask.

If you are in the process of designing a complex multi-layer heavy copper PCB and are looking for a high-quality and experienced manufacturer, feel free to reach out to us at, Best Technology can support you by OEM and ODM service to ensure your design is cost-effective and can be easily manufactured.

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Why Consider Even-Number Multi-Layer PCBs For Your Project?

Tuesday, March 7th, 2023

With the great demands about high-tech electronic equipment, although the single sided PCB or double-sided printed circuit boards have their advantages, multi-layer designs are more beneficial for some applications, that’s why the more and more popular and wide usage of multi-layer PCBs.


Currently in the market and electronic industry, almost of the multi-layer PCB have an even number of layers such as 8, 10 or 12 layers, why designers didn’t consider an odd-number layers? Today let’s explore the reasons together.

  • Higher cost spent

Normally the standard layers of a multi-layer PCB in the industry are even-numbers, and as the manufacturing technology becomes more and more mature, the cost of fabricating a multi-layer PCB is relative competitive.

But if you want to produce odd-numbers PCB, may the odd-number layers save the cost of material for one layer but the processing cost increase significantly to an even-numbers. Because the core structure requirement for odd layered PCB increases the production cost greatly. However, an even layered PCB can save these costs and reduce the overall manufacturing cost, so why not consider the even number layers?

  • Long lead time

Long delivery time is unescapable because of the immature fabricating technology. In particular with the odd-layer, the stack up will be unbalance. For example, if it’s an odd layered circuitry, due to the standard symmetrical requirement, the layers will be separated to 2 layers in a one side and another side is 3 layers, so one of the copper layers will be etched away and the odd layered PCB may create uneven weight during the copper plating stage and result in irregular plating issues. This non-standard, odd-layered stack requires an extra core process for layer bonding and adds to the manufacturing time and cost. So, it’s always recommended to use an even number of layers in the PCB stack-up.

  • Potential quality issue

Quality is very important and crucial for end-application, and the best reason of why not design an odd-number multi-layer PCB is the odd-number layers PCB is very easy to get twist due to the unbalance copper layers. When the PCB is cooled after the multi-layer circuit bonding process, the different lamination tension between the core structure and the foil structure can cause the PCB to bend when cooled. As the board thickness increases, the risk of bending becomes greater for composite PCBs with two different structures.  The key to eliminate circuit board bending is to use balanced layering.  Although PCBs with a certain degree of bending meet the specification requirements, subsequent processing efficiency will be reduced, resulting in increased costs. Because assembly requires special equipment and technology, the accuracy of component placement is reduced, so the quality will be damaged.

In addition, the twist of an even-number layers PCB can be controlled below 0.7% (IPC 600 standard), but odd layers unable to reach to this quality standard. What’s more, when the warpage of a circuit board greater than 0.7% will seriously affect the operation of Surface Mounted Technology (SMT) process and the reliability of the whole product. Therefore, the designers do not design odd layer generally, even if the odd layer enables to achieve the function, will be designed into false even layer, that is, 5 layers designed into 6 layers, 7 layers designed into 8 layers of board.

Anyway, more layers it is, more complex & difficult the manufacturing will be, and more expensive the cost will be, and the lead time of multi-layer PCB also is different from normal one. So you must choose a right supplier who can provide One-stop service include designing, evaluating, manufacturing or even repairing. Best Technology is an expert in the production of multi-layer PCBs for many companies around the world for over 16 years. Contact us right now and send us inquiries, we are so confident that we can be one of your most reliable suppliers in China.

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The Difference Between 2L MCPCB and Double Sided MCPCB

Monday, February 27th, 2023

In our last article, we know what a metal core PCB is, in this post, we will introduce what is the difference between 2L MCPCB and Double sided MCPCB. Please continue to read if you want to know more about metal core printed circuit board.

Today we will explain from these four contents as following:

  1. Stack up (structure)
  2. Heat dissipation
  3. SMD populate
  4. Manufacturing technology

Stack up of 2L MCPCB and Double Sided MCPCB

For a 2L MCPCB, the metal core is positioning on the bottom side of the MCPCB as a cooling carrier to the whole MCPCB, while the metal base of double sided MCPCB is located in the middle of two copper trace. In generally, some PTH (plated-through-hole) vias are needed to designed to connect the bottom and top traces.

Below are the stack ups of these two kinds of products, from the structure, we can easily distinguish which one is 2L MCPCB and which one is double sided MCPCB.

Heat dissipation of 2L MCPCB and Double Sided MCPCB

Due to the different structure of the two products, their heat dissipation performance is also different. The main reason is the heating of double-sided metal core circuits can be spread out through both top and bottom side, while the heating generate by SMD components of 2 layers circuit only can be dissipated through bottom (metal) side and the heat need to go down layer by layer. In addition to this, the dissipation of FR4 is not good than metal materials, so double-sided metal core printed circuits perform better heat dissipation performance than 2 layers MCPCB.

Surface mounted locations (SMD populate)

Nowadays, surface mounted technology (SMT) is widely used in printed circuit board industry, more and more designers prefer to populate electronic components of the circuit surface to achieve high density, stable electrical performance and high reliability. 2L metal core circuit boards and double-sided metal core circuits also show their different mounted locations in this aspect.

The populate location of a 2L MCPCB only available on copper trace side, that is top side. And a double-sided metal core PCB can mount components on both top and bottom side, because both of them exist copper trace on it.

Manufacturing technology

May somebody will curious about “Are these two products produced in the same process/technology?”

The answer is obvious “NO, they have a different laminate process when fabricating.”

Different with single layer MCPCB, double sided MCPCB requires an additional pressing step to laminate the thermal conductive layer and metal core together. But sometimes, some raw Metal Clad material vendor will supply board material which already laminated.

For 2 layers metal core PCB, due to it is made of a single MCPCB and a double-sided FR4 PCB, the first thing we should make a double sided FR4 PCB, then laminate the PCB together with the single MCPCB. But due to the thermal conductive layer (pure adhesive) is easy to overflow during laminating process, which will cause the poor adhesion and crack between metal core and FR4 PCB. In the meantime, to avoid such problem, an experienced operator is needed to proceed the laminated process. That is why the lead time and cost of a 2 layers metal core circuit is much longer and expensive.

This is the end of this post, if you still have some questions or difficulties about the metal core PCB, welcome to contact us at, our professional sales team and engineering team will give you a best solution for free.

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What is the DBC Ceramic Copper Oxidation Technology

Monday, February 20th, 2023

DBC (Direct Bond Copper) ceramic PCB also known as DCB ceramic, which is widely used in various type of high-power semiconductor, especially in IGBT package material by means of its excellent electricity and thermal conductivity of copper and the advantages of high mechanical strength and low dielectric loss of ceramics. DBC technology uses the oxygen-containing eutectic solution of copper to directly apply it to the ceramic. The key factor in the preparation process is the introduction of oxygen element, so the copper foil needs to be pre-oxidized in advance. Do you want to know what is the copper foil oxidation technology during the DBC ceramics manufacturing? Hereinbelow, we will introduce the oxidation process for you.

Oxidation technology of copper foil

Copper oxidation is divided into Wet Air Oxidation (including soaking oxidation and spraying oxidation) and Dry Oxidation.  Both oxidation methods can form CuO or Cu2O on the surface of copper foil.

  • Wet Air Oxidation (WAO)

i. Soaking oxidation

First, the copper is pickled with 3% dilute sulfuric acid, and then washed by the spray washing machine after overflow. Next, sent the copper into the mixed solution of potassium permanganate and copper sulfate (the concentration of potassium permanganate is about 31.6mg/L and the copper sulfate is about 95.4mg/L) for soaking and oxidation.  The oxidized copper is then washed with water and three-stage countercurrent washing, and then slowly pulled for dehydration and drying (the temperature is about 100℃) to complete soaking and oxidation.

ii. Spraying oxidation

Spraying oxidation is a kind of WAO, only the oxidation method become spraying. Spray oxidation is to spray copper with mixed solution of manganese nitrate and copper nitrate (concentration of about 3%) after pickling and washing.  The sprayed copper is dried directly in the tunnel kiln (the temperature is about 200℃).  In the drying process of tunnel kiln, the manganese nitrate and copper nitrate sprayed on the copper sheet are decomposed into copper oxide and manganese oxide.  The ratio of soaking oxidation and spraying oxidation treatment of copper sheet is about 5:5.

  • Dry Oxidation

Dry oxidation is very easy to process, put the copper into oxidation oven firstly, then heating up to 600~800oC for oxidizing around 30mins and then subjected to air cooling annealing.

Wet Air Oxidation VS Dry Oxidation

At present, the existing industry is widely used to finish the high-temperature annealing oxidation of copper then sintering with ceramic substrate, that is dry oxidation.  But this high temperature annealing, oxidation in one way has some drawbacks as following:

  1. Uneven oxidation. It will directly cause sintering defects during sintering, and the peeling strength will change greatly.
  2. Leaving conveyor belt marks.  Because the high temperature and oxidation process is transported by the conveyor belt, the existence of the conveyor belt mesh will affect the temperature distribution of the entire copper is not uniform, leaving marks/traces of the conveyor belt.  The result of sintering is to leave the corresponding trace on the bonding surface of CuAl2O3.
  3. High temperature annealing and oxidation will accompany the grain growth of copper. In the subsequent sintering process, the grain will continue to grow, which brings adverse effects on the mechanical properties and surface treatment of copper.  The copper surface grain produced by wet oxidation is fine, which is conducive to improving the mechanical properties of copper and eliminating the traces of conveyor belt. The main difference between wet oxidation and dry oxidation is shown in the bending resistance, heat resistance cycle performance and peeling strength, and these three indicators are significantly better than dry oxidation. Wet oxidation products can better meet the requirements of bending strength and heat resistance cycle performance.

So, this is the end of this post, Best Technology specialized in fabricating ceramic PCB (including DBC, DPC, AMB, HTCC and LTCC technology) for more than 16 years, we have rich engineering team and professional sales team can provide one-stop service for you. Welcome to contact us if you have any inquiries about ceramic PCB.

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How to choose surface finish on Printed Circuit Board?

Saturday, December 17th, 2022

When finish the PCB design, we should choose a suitable surface finish to protect traces from corrosion. Nowadays, the most popular surface treatments for PCB manufacturer to use are HASL/LF HASL, OSP and ENIG.

Different surface treatment has its unique functionality and the cost also is different. This article we will show you the pros and cons of the three surface finishing which use while the PCB manufacturing process.

HASL Surface Finish

HASL (Hot Air Solder Level) can be known as tin-lead HASL and lead-free HASL, it was the mainstream surface treatment technology in the 1980s, but with the increased of “small and high density” demands in PCB, there are less and less circuit boards use the HASL technology because it will cause the defective products due to the solder point are easy to leave on the board surface during SMT process. In view of this situation, some PCB board manufacturers or designers prefer use OSP or immersion gold to ensure the good quality products as well as smooth production process.

  • Tin-lead HASL


1) Economical and widely available.

2) Excellent solderability.

3)Better mechanical strength & lustrousness than lead-free HSAL.

Disadvantages: it is harmful to environment and violates RoHS compliance.

  • Lead-free HASL

Advantages: low cost, good solder performance and environmental.

Disadvantages: mechanical strength & lustrousness are not good than lead HASL.

In additional, due to the poor surface flatness of HASL circuit boards, neither leaded nor lead-free HASL is not suitable for soldering fine-pitch components or plated through-holes, because it will cause the short circuits and poor welding during the assembly process.



OSP (Organic Solderability Preservatives) also named as pre flux, the working principle is to generate a layer of organic film chemically on the copper surface to protect the surface from oxidation or vulcanization in the room environment. Meanwhile, OSP also can increase the oxidation resistance, heat shock resistance and moisture resistance of a PCB. 

OSP is equivalent to an anti-oxidation treatment, the protective thin film can be easily removed by the flux quickly under the high soldering temperature, then it makes the exposed copper surface immediately combined with the molten solder in a very short time to become a solid solder spot.

At present, the usage of OSP surface finishing process has increased significantly because it is appropriated for both low and high-end products. If your application has no surface connection functional requirements or storage life limitations, the OSP process is the most desirable surface treatment process.



1)With all the advantages of bare copper soldering, expired (more than 3 months) boards can also be resurfaced, but one time is better.

2)Good for fine-pitch, BGA and smaller components.

3)Low cost and easy to rework.

4)Simple process and easy to ensure quality.


1)OSP is easily affected by acid and humidity, so must be packed with vacuum.

2)Need to do surface treatment again if storage time more than 3 months.

3)It should be used within 24 hours after unpacking.

4)OSP is an insulating layer, so the test point must be printed with solder paste to remove the original OSP layer for electrical testing.


ENIG (Electroless Nickel/Immersion Gold) is one of a chemical nickel gold deposition method, the working principle is to generate a layer of coating by chemical REDOX reaction to get a thicker gold layer. Currently, ENIG is mainly used in the surface of the circuit board with connection functional requirements and long storage life.


1)Can be stored long time as well as no oxidation.

2)Good flatness surface and suitable for small solder point components.

3)Good solderability.

4)Can be used as the base material for COB wire bonding.


1)High cost than other two surface treatments.

2)Easy to exist black-pad issue during production process.


As we can know from above information, each PCB surface treatment has its own merit and demerit, you can choose the one according to the effect you want to reach, as well as your cost. 

If you don’t know which is best for you, you can send inquiry to us, our professional engineering team and PCB sales will choose the suitable one for you. Welcome to contact us if you have any other questions.

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