The techniques of this process are somewhat uncomplicated, and The main element is always to plug the pores and clean up the plugged solder mask. The minimum amount hole diameter of mechanical drilling ability has dropped from 0.4mm to 0.2mm or even smaller. The outlet diameter from the PTH is https://10-layer3-levelhdigoldfin06159.blogitright.com/31390207/fascination-about-2-layer-immersion-gold-power-pcb