Evaluation by three-point-bend and ball-on-ring tests of thinning process on silicon die strength

摘要

With the onset of ultra-compact packages, systems in package may include stacked dies and mechanical sensors. Thus the thinning of silicon becomes necessary. The risk of failure, especially die crack, is often a major concern in the reliability of electronic packages. Therefore chip strength assessment becomes necessary for reliability prediction. In this paper, three-point-bend test and ball-on-ring test are compared to evaluate the risk of fracture of a silicon die as a function of its thickness, and of surface quality induced by the thinning process. Five thinning processes and six thicknesses (from 300 urn down to 80 urn) are statistically evaluated.