Investigation of Thermally Grown SiO2 by Ion Microanalysis

摘要

Thermally, grown SiO2 layers on Si have been investigated by the technique of ion microanalysis. Results are presented which demonstrate the presence of high concentrations of electrically inactive and immobile species of Na and K in as-grown oxides. The immobile impurities are confined to an SiO2-Si interfacial or transitional region about 200 A wide. Results are also presented which distinguish a separate, highly mobile species of Na which is readily introduced into the oxides by subsequent processing. It is further shown that the excess Na can redistribute and penetrate into the Si substrate at 600 C. Evidence for the high mobility of Na ions introduced by ion implantation is also presented. Results are presented which demonstrate the existence of a damaged region in SiO2 layers containing implanted impurities. (Author)