Abstract
In semiconductor industry, production of ever flatter, thinner and larger Si wafer are required to fulfill the demands in high integration and cost reduction. A severe problem encountered in wafer thinning process is the warp and distortion of wafer induced by the residual stress and subsurface damage. Chemo-mechanical grinding (CMG) process is emerging process which combines the advantages of fixed abrasive machining and chemical mechanical polishing (CMP), offers a potential alternative for stress relief. However, since the sodium carbonate is used as additives in previously developed CMG wheels, the metal ions like sodium ion were possibly introduced on the machined wafer surface, and could risk in metal contaminations. In order to develop the high quality CMG wheel excluding sodium carbonate, CMG wheels with different recipe were developed. So far, CMG has been studied to investigate the effects of wheel geometry and grinding conditions on the removal rate, and effects of bond materials and additives on the surface quality in our previous researches. In this study, the focus was given to the wheel mechanical property (bending strength, elastic modulus) of CMG wheels. The difference in wheel properties is discussed by association with CMG performance including wheel wear and surface roughness. The result have demonstrated that the surface roughness of newly developed CMG silicon wafer is equivalent to that of CMG containing sodium carbonate as additive silicon wafer without any grinding marks.
