Simple and Effective Technique of Backside Deprocessing of Thin Flip Chip Package

Abstract This paper introduces a simple and effective technique of backside de-processing procedure. This technique reduces time and steps by simple wet etching. The front-side deprocessing requires many steps, such as wet and dry etching and parallel lapping, and also backside de-processing requires mechanical grinding to thin down the silicon thickness before wet etching. This paper introduces an effective way by skipping mechanical grinding and by etching at high temperature in case of thin flip chip. The backside silicon images are presented and compared after de-processing with TMAH and KOH which commonly have been used for bulk silicon etchant. The results show uniform backside images without any damage or residue. This backside de-processing technique was applied in two case studies to facilitate failure analysis.