A Novel Single Step Thinning Process for Extremely Thin Si Wafers

Abstract

The demand for extremely-thin Si wafers is expanding. Current manufacturing technologies are meeting great challenges with the continuous decrease in Si wafer thickness. In this study, a novel single step thinning process for extremely thin Si wafers was put forward by use of an integrated cup grinding wheel (ICGW) in which diamond segments and chemo-mechanical grinding (CMG) segments are alternately allocated along the wheel periphery. The basic machining principle and key technologies were introduced in detail. Grinding experiments were performed on 8-in. Si wafers with a developed ICGW to explore the minimal wafer thickness and grinding performance. The experimental results indicate that the proposed grinding process with the ICGW is an available thinning approach for extremely thin Si wafer down to 15μm