1.Back-drilling production process?

A. providing a PCB, the positioning hole is arranged on the PCB, and the positioning hole is used to perform a drilling positioning on the PCB and performing a drilling and drilling;

B. Electroplating the PCB after drilling a hole, and performing dry film sealing on the positioning hole before electroplating;

C. making an outer layer pattern on the electroplated PCB;

D. performing pattern plating on the PCB after forming the outer layer pattern, and performing dry film sealing treatment on the positioning hole before pattern plating;

E. Using the positioning hole used in a drill to perform back drilling positioning, and using a drill to back drill the plating hole that needs to be back drilled;

F. After back drilling, wash the back hole with water to remove the drill cuttings left in the back hole.