Patent ID: 8533942
Filing Date: 2013-09-17
Classification: H05K,Y10T

Abstract:
1. A process for making a multilayer printed wiring board, comprising performing steps (i) through (v) in the order of from (i) to (v): (i) forming an insulating layer by laminating a prepreg, said prepreg comprising a glass cloth impregnated with a thermosetting resin, on at least one surface of a circuit substrate having a conductive circuit on its surface; (ii) forming, by laser irradiation, a via hole in said insulating layer, such that a said conductive circuit is exposed at the bottom of said via hole; (iii) subjecting glass cloth projecting into said via hole to a glass etching treatment with a glass etching solution, to obtain a glass etching-treated via hole; (iv) subjecting said glass etching-treated via hole to a desmear treatment with an oxidizing agent solution; and (v) forming a via which is connected to said conductive circuit by said via hole.