Defects in as-grown thermal oxide were investigated by means of photoluminescence spectroscopy, using synchrotron radiation as the illumination source. A band at 3.3eV was observed, under excitation at 5eV, in dry thermal oxide at room temperature. The photoluminescence band was also observed in oxide which was annealed in forming-gas, and the 3.3eV photoluminescence was either enhanced by subsequent vacuum annealing or was suppressed by H exposure. Photoluminescence measurements of oxynitride film showed that the effect of N incorporation upon the 3.3eV photoluminescence was less than that of H. The wide observability of the 3.3eV photoluminescence band in oxide films which were prepared under various conditions indicated the intrinsic nature of the defects in thermal oxide which were introduced during the thermal oxidation of Si.
Defects in Thermal Oxide Studied by Photoluminescence Spectroscopy. H.Nishikawa, J.H.Stathis, E.Cartier: Applied Physics Letters, 1999, 75, 1219-21