Heavy Copper Printed Circuit Boards

The standard copper weight for a conventional PCB is 1 oz per square foot, which corresponds to a thickness of approximately 35 micrometers (1.4 mils). This is sufficient for most consumer electronics. Heavy copper PCBs start above 3 oz and can extend to 20 oz for high-power, high-current, and thermally demanding industrial or military applications.

1 oz copper on a PCB refers to a copper layer thickness of approximately 35 micrometers (about 1.4 mils), derived from spreading one ounce of copper over one square foot of board area. It is the industry baseline for standard electronics. Heavy copper PCBs use 2 oz and above, with FX PCB offering up to 20 oz for extreme power applications.

For standard PCBs, a plated through-hole copper wall thickness of at least 25 µm is generally recommended per IPC standards. For heavy copper PCBs handling high currents, thicker copper walls at PTH holes significantly improve mechanical strength and current capacity. FX PCB uses a multiple-step plating and etching process to ensure uniform copper wall integrity across all layers.

A PCB is classified as heavy copper when the copper weight exceeds 3 oz per square foot (approximately 105 µm thickness). FX PCB's heavy copper range spans from 2 oz to 20 oz, with ultra-heavy variants at 10–20 oz used for the most demanding power electronics, military radar systems, EV modules, and industrial power distribution applications.

Heavy copper PCBs are widely used in power electronics, automotive (especially EV components), military and defense (radar, weapon control, surveillance), aerospace and satellite systems, medical devices, nuclear and solar energy, industrial welding equipment, UPS systems, and rail traction systems — anywhere high current loads and thermal management are critical design requirements.

Yes. FX PCB manufactures multilayer heavy copper PCBs with up to 24 layers for 3–4 oz copper (samples), 20 layers for 5–6 oz, and up to 12 layers for 7–12 oz configurations. Multilayer heavy copper boards allow significant product size reduction by consolidating high-power circuitry into compact, high-density designs suitable for advanced aerospace and industrial applications.