Investigation of high reliability micro bump plating technique ontape carrier

摘要

This paper describes the continuous copper bump plating techniquefor TAB tape carriers. We investigated the copper plating bath,pre-treatment agents and the bath agitation method. For high speed anduniform plating, the selection of an appropriate copper plating bath ismost important. Through our investigations, we found the most suitablebath for copper plating bumps, which obtained good appearance and highreliability bumps at 20 A/dm2 or more. The tape carriers withcopper plating bumps were applied to the new stacking board and theburn-in socket substrate for a 0.5 mm pitch BGA package. In both cases,it was confirmed that the tape with bumps had high reliability. Then, acontinuous reel to reel plating machine for TAB tape carrier wasdesigned and manufactured