Alternative Technique of Half-etching for Printed Board Manufacturing by Chemical Mechanical Polishing (CMP)

Abstract

In order to react to high pattern density in printed boards, copper half-etching technique (HET) has been applied to the manufacturing processes (before the pattern formation process), where the H₂SO₄-H₂O₂ system is used as an etching solution. For the HET, solution control during the etching is complicated, and the production costs become expensive. Consequently, alternative technique of the HET is desirable. We propose a new technique, which is based on chemical mechanical polishing, as the alternative technique. We will reveal the CMP solution characteristics, the mechanism, and the polishing conditions during CMP, and the chemically mechanically polished surface properties.