BLIND HOLE PROCESSING METHOD FOR PRINTED CIRCUIT BOARD

摘要

A blind hole processing method for printed circuit board involves the following steps: drilling a plurality of through-holes in each sub-board respectively, plating copper on the inner wall of each through-hole and etching each sub-board to form wirings and pads; gluing prepregs on each sub-board and processing the prepreg on the top surface of each substrate to obtain holes; covering the whole bottom surface with the prepreg on bottom surface of each sub-board; gluing a copper foil on the prepreg on top surface and bottom surface of each sub-board respectively and pressing the sub-boards with the prepregs under high temperature; detaching the copper foil of the prepreg on bottom surface of each sub-board, and arranging adhesive prepreg between bottom surfaces of two sub-boards, pressing the two sub-boards integrally by the adhesive prepreg; forming long through-holes by processing the substrate with drilling, copper depositing, plating and patterning; detaching the outer copper foils of the printed circuit board to form blind holes. The invention has the advantages of no residual chemicals in the deep blind holes and no erosion to the wall of the blind holes.