In this paper, we present a high yielding 20μm pitch CuSn electroplated microbump flip chip process. The 10μm diameter bumps are organized in an area array, consisting of 440 daisy chains of 1766 bumps each. The 2cm × 2cm flip-chipped dies consist of about 1M bumps in total. The influence of processing materials like seed layer etchants and cleaning agents on the electrical performance of the daisy chains is discussed. Further Ti/Cu versus TiW/Cu seed layers for electroplating are compared. Finally inspection methods for tracing back electrically measured failures are screened.
Published in:
Electronic Components and Technology Conference (ECTC), 2011 IEEE 61st
Date of Conference: May 31 2011-June 3 2011