Wafer Warpage Evaluation of Through Si Interposer (TSI) with Different Temporary Bonding Materials

Abstract

This paper investigate the evolution of wafer warpage at different stages of a Through Si interposer (TSI) process flow, with reference to 2 different types of temporary bonding material. Comparison was done between solvent based and mechanical based debonding adhesives. The TSI fabrication includes 4 layers Cu damascene (BEOL) metal, front-side UBM, post-bonding backgrinding, TSV reveal etch and backside UBM.