The study of the resin-bond diamond wheel for IC silicon wafer nanoscale roughness back grinding

Abstract

Resin diamond grinding wheels are applied to the back thinning grinding (back grinding) of IC silicon wafers. The wheels should have very high performance because the silicon wafers ground by them can reach nano-scale roughness, micron-scale damage layer thickness and micron-scale surface type accuracy. The depth of subsurface damage and Ra value of subsurface roughness are two important indicators to represent the grinding quality of IC silicon wafer surface and their numerical values also reflect the quality of silicon wafer grinding wheels. The paper researches the influence of domestic and imported resin diamond grinding wheel 1200# on the surface grinding quality of the back ground silicon wafer, the detection methods of the silicon wafer's subsurface damage depth and roughness and the detection data of the wheel ground silicon wafer's subsurface damage depth and subsurface roughness value, Ra. Meanwhile, it analyzes the corresponding relationship between the wheel grinding power (current value) and the silicon wafer's subsurface damage depth. The research results show, the performance of the domestic resin-bond diamond grinding wheel 1200# meets the technical requirement of the resin diamond grinding wheel. Its subsurface damage depth is 0.79µm and its average surface roughness value Ra is 9.76nm; The surface damage depth of the imported grinding wheel is 1.55µm and its average surface roughness value Ra is 11.811nm.