A damaged layer is always formed on the surface after Si wafer is diamond ground and chemomechanical polished. This layer is amorphous and typicallycontains a thin film of oxide (SiO_x, x <=2) and underneath coexists a high density of defects. As the cross-section transmission electron microscope is used to investigate the damaged layer, the z-contrast is not high enough to reveal the oxide layer and therefore determine the thickness. In this study, Fourier transformed infrared spectroscopy (FTIR), Auger electron spectrometry (AES), and ellipsometry are used to characterize the Si wafers after ground using electrolytic in-process dressing (ELID) with diamond under various grain size. The samples are respectively designated as #1200, #2000, #4000, #6000, and #8000, which are diamond ground only, and #4000P which is first ground and then chemomechanical polishing. The damaged layer contains a thin layer of SiO_x in which the thicknesses as determined by FTIR vary for various samples: 5approx15 nm for #2000, #4000, and #6000, 4approx5 nm for #1200, and less than 4 nm for #8000 sample. Whereas, as using AES to monitor the depth profile of oxygen, the oxygen distribution of this SiO_x layer is continuous rather than abrupt. The carbon is also detected for #2000, #4000, #6000, and #4000P specimens. The incorporation of oxygen and carbon either result from local heating or wear of diamond will be discussed in this study.
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