Development of 30 micron Pitch Bump Interconnections for COC-FCBGA

Abstract

We developed the flip-chip bonding technology on chip-on-chip (COC) package with ultra-fine pitch bump, which leads advanced high performance devices. On this package, the realization of the metallographic behavior in the micro-bump interconnection is the substantial issue for achieving good bondability and reliability. In this paper, to implement flip-chip BGA package with COC structure (COC-FCBGA), the metal systems of micro-bump and the dimension especially metal plating thickness have been optimized by precise analysis. And it is confirmed that the specification we fixed on this package would meet sufficient quality level for fine pitch bonding. This COC-FCBGA technology will meet demands for high-end system solutions in very near future