Heavy Copper PCB Manufacturer | 3 oz to 10 oz Extreme Tolerances

A heavy copper PCB is formally classified as any printed circuit board manufactured with 3 oz/ft² (105 µm) or more of finished copper on either inner or outer layers. While standard commercial PCBs utilize 0.5 oz to 1 oz copper (18–35 µm), heavy copper boards can carry continuous currents of 50A to 120A+ and operate at elevated temperatures without thermal runaway.

APTPCB manufactures up to 10 oz/ft² (350 µm) finished copper on multi-layer boards (up to 16 layers), and up to 20 oz/ft² (700 µm) on specialized single/double-sided power distribution panels. We also support hybrid differential stackups combining heavy copper power planes with standard 1 oz signal layers.

We use high-flow, high-resin prepregs combined with optimized hydraulic vacuum press cycles. The resin content is precisely calculated against the copper pattern density to ensure every inter-trace trough is 100% encapsulated with void-free dielectric resin before curing, verified via metallurgical microsection cut inspection.

Heavy copper PCBs are standard in automotive EV battery management systems (BMS), power converters, industrial motor drives, solar inverters, military radar power supplies, aviation distribution panels, and high-current welding machinery where high reliability and compact thermal management are non-negotiable.

Yes, but they require careful thermal profiling due to their high thermal mass. APTPCB's PCBA facility utilizes 10-zone reflow ovens with nitrogen atmospheres and programmable selective soldering systems to ensure full solder wetting and barrel fill on heavy through-hole pins without damaging adjacent heat-sensitive surface mount components.