Heavy Copper PCB

  • A heavy copper PCB is a board that uses a heavy copper circuit.
  • You can also call it a thick copper PCB. After all, the copper weights range from 4 oz/ft2 to 20 oz/ft2.
  • Plus, it comes with different perks like cost-effectiveness (long-term), low impedance power distribution, etc.

What Is Heavy Copper PCB?

A heavy copper PCB is a board that uses a heavy copper circuit. This type of PCB undergoes special etching and plating methods like differential etching and step plating. You can also call it a thick copper PCB. After all, the copper weights range from 4 oz/ft2 to 20 oz/ft2.

So, with the thick copper board, there’s no need to produce high-current/high-power circuits and control circuits on different boards. Also, the thick copper plating comes with a highly dense and simple board structure.

And it’s possible to integrate control circuits and high-power circuits on the same board. Plus, it comes with different perks like cost-effectiveness (long-term), low impedance power distribution, etc.

Benefits of Thick
Copper PCBs

The following are the benefits of Heavy Copper.

  • The thick copper board helps to transfer heat to the external heatsink and convey a higher current. And this is possible with the help of its plated vias

  • The board can support high current frequency, repeated thermal cycling, and high temperatures

  • The board reduces the chances of having circuit failure

  • Its PTH holes and connector sites have high mechanical strength

  • The board has increased resistance to thermal strains

  • The PCB has a compact product size with different copper weights. And each of the copper weights is on the same layer of circuitry

  • It carries heavy current

  • It doesn’t have complex wire bus configurations

  • The board comes with exotic materials. These materials are useful for enhancing the board’s mechanical characteristics

Some parts of the board that has heavy copper deposition can serve as heat sinks. Besides, you can interface it to cold plates as well.

Heavy Copper PCB/ Thick Copper
PCB Capabilities

We’re one of the leading thick copper circuit board producers in China. So, here’s a table explaining the capacity of our boards:

  • Properties
  • Outline:
    V-cut, punching, routing
  • Holes:
    Maximum AR (Aspect Ratio) of holes – 10:1 Minimum drill bit hole size – 0.012” Minimum hole size: 0.008” + 0.005” / -0.008”
  • Minimum silkscreen line width:
    8 MIL
  • The material at the base:
    Aluminum, Polyamide, FR/4 all TGs, Copper, Ceramic, Teflon
  • Soldermask:
  • Thickness of Copper:
    4 – 10 Oz
  • Number of layers:
    2 – 16
  • Vias:
    Buried and Blind
  • Surface finishing:
    HASL, OSP, and immersion Gold
  • Controlled impedance:
    +/- 10%
  • Maximum panel size:
    22.8" by 18.9"
  • Quality grade:
    Standard IPC 2
  • Finished thickness:
    0.020" – 0.275"
  • Minimum solder dam width:
    5.5 MIL
  • Minimum Soldermask clearance:
    6 MIL

Applications of Heavy Copper
Circuit Board

Thick copper pcb are using in the industrial applications, such as

Automotive Industry

Industrial controls

Welding equipment

Electrical applications

Below are where heavy copper pcb in use.

HVAC systems

Power Electronics

Power line monitors

Solar power converters

Power converters for railway electrical systems

Nuclear power applications

Protection relays

Welding equipment

Safety and signal systems

High power rectifiers

Torque controls

Power supplies for radar systems

Excitation systems for power regulators

PCB Copper Thickness

Why do you need a PCB copper thickness calculator?

Well, the tool is a vital design parameter in PCB design. That is, it helps you to know the right amount of current that you need to transport without overheating and damaging your board.

It also helps to give you an estimate for a particular current and copper weight. Plus, you should note; when you have a higher current, it would need thicker traces. Also, when you have a thicker copper weight, it permits thinner traces.

Heavy Copper PCB Design

Before you dive into the design process of thick copper PCB, it’s crucial to consider parameters like:

The spacing

The type of parts

Ideal dimensions

Here is a table that summarizes the dimensions:

CriteriaBaseline thickness of copper foil
Loss (mils/mm)Ca. 3 / 0.08Ca. 5 / 0.13Ca. 6 / 0.15Ca. 7 / 0.18
Minimum spacing (mils)13152027
Minimum path width (mils)12141825

With these parameters in mind, you can do the following:

1. Take note of the copper fill levels in the inner layers. The reason for this is to avoid very low fill levels. If this happens, at low resins levels, voids will occur between the layers of the board. And it will result in delamination.

2. It’s best to pick the number and types of prepregs with software that helps you achieve multilayer build-up designs.

3. The galvanic coating is important. And considering that you’re dealing with a heavy copper PCB, you’ll use more galvanic copper.

4. Ensure that the layers of your solder resist are thick. That way, you’ll adequately guard the mosaic edges. For instance, your final circumferential thickness should have a value of at least 0.25mm higher than its initial thickness.

Your Heavy Copper PCB Manufacturer
in WellPCB

One thing is certain about heavy copper PCB—it needs special technology to achieve the best results. And despite the challenges involved in its fabrication, we deliver quality at the best price.

Plus, we have been in the business for years. So, you can count on our experience to build the best PCB based on your specifications. Our expertise doesn’t stop at PCB assembly. We conveniently handle small to a large volume of board fabrication. While at it, we stay committed to following strict standards

FAQs of Thick Copper PCB

1. How thick is the copper on a PCB?

The internal layer of a standard PCB usually has about 1 ounce of copper which translates to approximately 35µm thickness. But, the finished copper weight selection is 2 ounces which are approximately 75µmn in thickness.

2. How do you choose the thickness of PCB copper?

You can choose the thickness of PCB copper by determining the width. So, if the width can put up with the average to maximum operating temperature, that's the thickness.

3. How do you remove unwanted copper from a PCB in the manufacturing process?

You can remove unwanted copper from a PCB by etching. The procedure is subtractive. And it involves using a temporary mask to protect the wanted parts of the laminate. Then proceed to use acid to remove unwanted copper while the other parts are protected.

4. Why is copper used in PCB?

The reason why copper is a thing in the PCB world is that the element transmits signals effectively. And in the process, it doesn't lose electricity.

5. What is the base copper weight?

Base copper weight refers to the quantity of copper that's present on the PCB before plating

6. What to consider for Heavy Copper PCB's layout structures?

First, you need to consider the circuit layers, layer count. Then the external layers (outer layers). The layers of copper/copper layers determine the layers of Printed Circuit Boards.

7. For heavy copper standard features, what else needs to pay attention to?

Well, heat dissipation is what you need to consider. Also, the heat transfer,thermal stress,thermal resistance,thermal expansion . Besides, the elevated current, current flow, power loss, etc.

8. What to consider from the common designs to the copper PCB manufacturing in the PCB industry?

That's a lot to consider in the heavy copper board . Firstly, copper PCB solutions-the circuit size(product size), copper PCB material (base material, FR4-High Tg,etc.), Then, the copper thickness requirements, like ounces of copper/demand of copper, copper PCB thickness, extreme copper thickness. Also. the plating techniques in heavy copper plating , such as electroplating. besides, board surface treatment, like finishing HASL. Other Heavy Copper and extreme copper circuit manufacturing process are also essential in PCB Technologies , such as copper etching,copper traces, solder masks.

9. Should I choose regular circuit boards or high-current circuits?

Well, that depends on your need. For more about the PCB manufacturing service, like copper PCB quality, electrical circuits, you are welcome to contact our team.