Effect of calcium fluoride on grinding performance of resin-bonded diamondgrinding wheel for silicon wafer

Solid lubricant Calcium fluoride (CaF₂) with different volume fractions is added into resin-bonded diamond wheels for single crystal silicon wafer grinding. Its influence on surface structure and wear ratio of the wheel, as well as the spindle current of grinding machine, is analyzed. The surface roughness of the wafer and the thickness of damage layer on its surface are measured and calculated. Results show that as the content of CaF₂ increases, the current, the wear ratio and the surface roughness and damage layer thickness all decrease. When the volume fraction of CaF₂ added is 25%, the current is about 6.4 A, and wear ratio of wheel decreased to 0.448 6 μm, with R_a 0.056 μm, R_y 0.382 μm and R_z 0.396 μm on the wafer surface and thickness of damage layer0.559 6μm. In conclusion, the performance of resin-bonded diamond wheels and the quality of machined single crystal silicon wafer could be enhanced by adding CaF₂ as solid lubricant, and the best volume fraction of CaF₂ is 25%.