Enhanced Conduction In Sipos Films With High Oxygen Content

Abstract

AbstractPolysilicon films with high oxygen content (SIPOS) have been prepared by LPCVD. These films have a two-phase structure with silicon crystallites surrounded by amorphous oxide, as confirmed by TEM and HRTEM measurements. Increasing the ratio of nitrous oxide to silane, R, during growth allows us to vary the oxygen concentration. Contrary to expectation, we observe a region where conduction increases as R is increased from 1 to 10. This can be accounted for by deviations from monotonicity in the dependence of silicon volume fraction on R. We also observe some influence of the SIPOS/silicon interface on conduction.