Chip to chip interconnection for system in packaging using Cu stud bump

Abstract

The current market trend for chip on chip connection is mainly using copper pillar. The copper pillar technology has been around for many years and advances in the copper pillar technology have grown steadily over the past few years. The main issue with copper pillar is the cost. Bumping a single piece of 12 inch wafer will cost approximately above USD100 - 200. The alternative low cost method studied in this paper is by utilizing copper stud bumps with the combination of anisotropic conductive adhesives to create the inter-metallic connection between the top die and the bottom die.