SOFT GOLD PLATING

Website:
https://rushpcb.com/soft-gold-plating-2/

Manufacturers traditionally use a thick layer of soft gold on PCBs for Gold ball wire bonding. This requires plating the Copper traces on the PCB with a layer of Nickel, followed with an electroplated layer of soft Gold, measuring about 30-50 µin in thickness. The properly plated Gold layer forming an excellent surface for wire bonding. Although the method is eminently suitable for fine-pitch Gold ball bonding, it is expensive.