Heavy Copper PCB Manufacturer

High-quality, quick-turn heavy copper PCB fabrication services.

If you’re in search of a reliable and efficient solution for your high-current and high-temperature applications, you’ve come to the right place. Our heavy copper PCB boards are designed to handle the toughest electrical and thermal demands, making them a go-to option for a wide range of industries.

At PadPCB, we pride ourselves on delivering top-quality heavy copper PCB boards that are built to last. Our advanced manufacturing processes and state-of-the-art equipment ensure that every board we produce meets or exceeds industry standards, so you can be sure you’re getting a product that you can rely on.

heavy copper pcb

Our Capabilities

PadPCB is a specialist in heavy copper PCB fabrication. We design and manufacture high-quality thick copper PCBs at competitive market prices. We utilize copper weights of up to 15oz (525μm). Check our capabilities in the following table:

Base MaterialFR/4 all TGs, Aluminum, Ceramic, Teflon, Polyamide, Copper
Quality GradeStandard IPC 2
Copper Thickness4 Oz – 10 Oz
Extreme Heavy Copper20 Oz – 200 Oz
SoldermaskRed Oil/Green/Blue/Black/White
Surface FinishingImmersion Gold, OSP, and HASL
OutlinePunching, Routing, V-Cut
Maximum Panel Size22.8 ʺ *18.9ʺ
Maximum Number of Layers16
Finished Thickness0.020 ʺ – .275 ʺ
Minimum Soldermask Clearance6 MIL
Minimum Solder Dam Width5.5 MIL
ViasBlind and Buried Vias
HolesMinimum Drill Bit Hole Size: .012ʺ
Minimum Holes Size: .008″ +.005″/-.008″
Maximum Hole Aspect Ratio = 10:1
Controlled Impedance+/- 10%
Minimum Silkscreen Line Width8 MIL

Frequency Asking Questions about thick copper PCB

Table of Contents

What is heavy copper PCB boards?

Heavy copper PCB boards are printed circuit boards that feature a thicker layer of copper than standard PCBs. These boards typically have copper thicknesses ranging from 3 oz/ft² (approximately 1mm) to 20 oz/ft² (approximately 7mm) or more, which is significantly higher than the 1 oz/ft² (approximately 0.035mm) of copper typically found on standard PCBs.

Heavy copper PCBs are designed to handle high-current and high-temperature applications, making them ideal for use in power electronics, automotive electronics, and industrial equipment. The thicker copper layers allow for better thermal management and reduced voltage drops, which can help to improve the overall performance and reliability of the electronic system.

Benefits of heavy copper PCB

The heavy copper PCBs are a reliable wiring platform. Industries are increasing the use of these thick PCBs. Here are a few benefits that these PCBs offer:

  • Multiple uses: The weight of heavy copper PCB affects the board quality and performance. So, not all boards can endure these PCBs. Heavy copper PCB boards are mainly used across devices where power and signal levels vary.
  • Compact size: A heavy copper board can withstand high current, high temperature, frequency, and recurring thermal cycles. This sustainability is the result of many layers stacked upon a single layer. This multiple stacking decreases the total size and weight of the board, thus creating tiny but high-performing circuits.
  • Thermal resistance: Regular PCB boards’ fan cooling system cannot disperse the high heat generated by them. As a result, this heat degrades the PCB quality by affecting soldered joints and destroying them. However, heavy copper PCBs have a high conducting capacity.; thus, they create less heat which is dispersed easily.
  • Better load sharing: There is no need to create multiple duplicates and parallel layers in heavy copper PCBs. The numerous parallel layers create load-sharing issues. However, in heavy copper PCBs, you can combine the copper with copper vias, thus avoiding forming multiple layers.
  • Board with high mechanical strength: As in heavy copper PCB, multiple layers and plated-through holes increase its overall strength.

Application of heavy copper PCB

You can use Heavy copper Printed circuit boards for different purposes, such as heat dissipation, power converters, high power distribution, and planar transformers. Several industries require heavy copper clad boards for their electronic controls. Electronic devices and power supply systems also use heavy copper PCBs extensively.

Several industries that use heavy copper PCB boards are:

  • Automotive industry
  • Power supplies and power converters
  • Welding equipment
  • Torque controls
  • Overload relays
  • Power line monitors
  • Power distribution
  • Solar panel manufacturing
  • Protection relays

How is heavy copper PCB fabricated?

The fabrication of heavy copper PCB requires etching and plating. With these techniques, PCB manufacturers increase copper thickness in sidewalls and plated holes. However, you cannot opt for a normal etching process as it results in uneven etched margins. Here, you need a unique etching and plating process to add that extra thickness of copper, and these processes result in straight and even margins.

During the fabrication process, heavy copper PCBs are electroplated. This process increases the thickness of the PTH barriers. This technique also results in shrinkage of layer count and reduction of impedance reduction. However, if PCBs undergo multiple cycles, the plated holes may become weak. 

There are mainly two methods of fabricating heavy copper PCBs:

Embedded copper method:

PCB fabrication takes place using a flat surface. In this, manufacturers insert prepreg resin along with copper, and the thickness of copper depends on the thickness of resin.

Blue bar method:

In this process, manufacturers insert thick copper bars into PCBs to add thickness and transmit additional current. As only a few lines of copper can carry significant current in high power circuits, it helps reduce the extra weight of PCB. However, it is essential to consider the level of copper fill between inner layers to prevent extra delamination in multilayer boards.

Difference between standard PCB and thick copper PCB?

  • The main difference between a standard PCB and a thick copper PCB is the thickness of the copper plating on the circuit boards. On a standard PCB, the copper layer weighs one ounce to 35 micrometres, while on a heavy copper PCB, it weighs around 4 oz to 140 micrometers.
  • Standard PCBs cannot conduct high current values, while a heavy copper PCB can transmit significantly high current levels.
  • Heavy copper PCBs have higher mechanical strength than standard PCBs. A thick copper PCB can enhance heat conductivity while handling mechanical stress. 
  • Standard PCBs use copper etching and plating techniques in fabrication, while a heavy copper PCB uses step plating and differential plating. 
  • Heavy copper PCBs are capable of efficient thermal distribution, they are suitable for high-end applications where standard PCBs do not work.

Design considerations for heavy copper PCB board

  1. Reasonable direction of PCB circuit line design

In order to prevent mutual interference, the line directions should be linear (or separated) and must not blend with each other. Such as input/output, AC/DC, strong/weak signal, high frequency/low frequency, high voltage/low voltage, etc…

The best direction is in a straight line, but generally not easy to achieve, the most unfavorable direction is the ring, but fortunately can be set up to improve the isolation belt.

For DC, small signal, and low voltage PCB design requirements can be lower. So, the “reasonable” is relative.

2. Arrange power filter/decoupling capacitors reasonably

Capacitors are set up for switching devices ([gate circuits) or other components that require filtering/decoupling, and these capacitors should be arranged as close to these components as possible. If they are too far away, they will have no effect.

3. Number of vias, solder joints and line density

Wire holes should be minimized in the design. If the density of parallel lines in the same direction is too high, it is easy to connect together when welding. Therefore, the linear density should be determined according to the level of the welding process.

If the distances between the solder joints is too small, which is not conducive to manual welding, the welding quality can only be solved by reducing the I efficiency. Therefore, the determination of the minimum distance of solder joints should comprehensively consider the quality and work efficiency of welding personnel.

4. Choose the right line width and buried via size

High-voltage and high-frequency lines should be smooth, without sharp chamfers, and corners should not be at right angles. The ground wire should be as wide as possible, and it is best to use a large area of copper, which can greatly improve the problem of the grounding point. 

The size of the pad or hole is too small, or the size of the pad does not match the size of the drilled hole properly. The former is unfavorable to manual drilling, and the latter is unfavorable to CNC drilling. It is easy to drill the pad into a “c” shape, but it is heavy to drill off the pad. The wire is too thin, and there is no copper plating in the large area without wiring, which is easy to cause uneven corrosion. Therefore, the role of setting copper is not only to increase the ground area and anti-interference.