Heavy Copper PCB Manufacturing: Trusted Suppliers and Factories in China for Quality Production
What is a heavy copper PCB?
Double-sided printed boards are usually made of epoxy glass cloth copper foil. It is mainly used for communication electronics with high performance requirements Equipment, advanced instruments and electronic computers, etc.
- Copper thickness > 2 oz (70 μm)
- Preferred term over “thick” copper PCB
- 2 oz (70 μm)
- 3 oz (105 μm)
- 4 oz (140 μm)
- 6 oz (210 μm)
- 8 oz (280 μm)
- 10 oz (350 μm)
- Typically compatible with FR-4 dielectric
- Mostly used for inner layers rather than outer layers
- Plated through holes (PTHs) often need to be plugged/filled
- Requires careful registration and lamination
Heavy copper inner layers improve thermal performance and current carrying capacity useful for applications like LED lighting, power electronics, and electric vehicle inverters.
It is a PCB made with two or more conductive copper layers. The conductive foil appears to be thicker than on standard PCBs. The different inner layers are processed in pairs (on a core) and then bonded together using prepreg as the insulating layer. The layers are then placed in such a way that both sides of the PCB can be used to mount components with additional tracking/electrical connections on the inside of the board. Vias are used as a source of the electrical connections between the different layers of the PCB.
More and more products are using heavy copper PCBs, for example EV-chargers, high current systems and power storage systems.
| Feature | AREX's technical specification |
|---|---|
| Number of layers | 4 – 22 layers standard, 30 layers advanced, 40 layers prototype, much depending on copper thickness. |
| Technology highlights | Multiple layers of epoxy glass fiber bonded together with multiple layers of copper of varying thicknesses. |
| Materials | High performance FR4, halogen-free FR4 |
| Copper weights (finished) | 18-210µm, advanced 1050µm / 30 Oz |
| Minimum track and gap | 0,075mm / 0,075mm (very much depending on copper thickness) |
| PCB thickness | 0.40mm – 7.0mm, Min thickness depending on number of layers and copper thickness |
| Maximum dimensions | 580mm x 1080mm, advanced 610mm x 1400mm |
| Surface finishes available | HASL (SnPb), LF HASL (SnNiCu), OSP, ENIG, Immersion Tin, Immersion Silver, Electrolytic gold, Gold fingers (HASL / LF HASL not recommended) |
| Minimum mechanical drill | 0.20mm |
Frequently Asked Questions
A heavy copper PCB is defined as a printed circuit board with a finished copper thickness of more than 2 oz (70 μm).
Common heavy copper weights range from 2 oz (70 μm), 3 oz (105 μm), 4 oz (140 μm), up to 10 oz (350 μm), with advanced options reaching up to 30 oz (1050 μm).
They are widely used in demanding electronics such as LED lighting, power electronics, electric vehicle (EV) inverters, EV-chargers, and high-current power storage systems due to their superior thermal performance and current-carrying capacity.
They are typically compatible with standard high-performance FR4 and halogen-free FR4 dielectrics.
Standard production supports 4 to 22 layers, with advanced capabilities up to 30 layers and prototype options up to 40 layers, depending on the specific copper thickness.