Wet-Chemical Silicon Wafer Thinning Process for High Chip Strength

Abstract

We proposed the wet-chemical Si wafer-thinning process and evaluated the damage caused by this process. For the damage evaluation, we measured the die fracture stress and fracture energy, and compared various wafer-thinning processes (backgrinding, wet-chemical Si wafer-thinning, backgrinding + chemical mechanical polishing, backgrinding + wet etching). The result of comparative study shows that wet-chemical wafer-thinning process has very high fracture stress/energy and demonstrates that the damage of wet-chemical Si wafer-thinning process is very small.