2020 Volume 71 Issue 8 Pages 516-520
Along with the recent remarkable development of the electronics industry, further miniaturization and higher performance of electronic devices are anticipated. Reaching these objectives necessitates the miniaturization of built-in parts. Miniaturizing one such component, printed circuit boards（PCBs）, the base on which electronic components are mounted, requires increased density. A mainstream manufacturing method, semi-additive method, enables fine wiring formation with plating and etching technologies to facilitate miniaturization and to enhance the reliability of PCB manufacturing and related component-mounting technologies. For this study, we measured AC impedance associated with etching processes using a formic acid type roughening solution under various conditions. We assessed the correlation between outcomes of etching processes and AC impedance methods. Changes of copper etching mechanisms with variation of the etching solution pH were revealed by AC impedance measurements.
