Effect of ultraprecision grinding on the microstructural change in silicon monocrystals

The effect of ultraprecision grinding on microstructural change in silicon monocrystals, such as surface roughness and dislocation structure, was investigated both experimentally and theoretically. The study found that there exists an additional concentration of oxygen and carbon in an amorphous layer for all investigated grinding regimes with their distributions dependent on the grinding variables. It showed that two atomic bonding configurations exist in the amorphous layer, i.e. silicon oxide in the surface region followed by amorphous silicon. The research established that the grinding table speed affects the thickness of the dislocation layer in the subsurface. Increase of the table speed leads to a thicker dislocation zone and created microcracks. The paper concludes that the ductile mode of material removal in the grinding of silicon monocrystals is due to the formation of the amorphous phase. (C) 1998 Elsevier Science S.A. All rights reserved.