Buried oxide films in Si, that had been formed by the implantation of O ions, were characterized by the photoluminescence that was excited by KrF (5eV) excimer laser and synchrotron radiation. Two photoluminescence bands were observed, at 4.3 and 2.7eV. The 4.3eV band comprised 2 photoluminescence excitation bands, at 5.0 and 7.4eV, and its decay time was 4.0ns for the 5.0eV excitation and 2.4ns for the 7.4eV excitation. The decay time of the 2.7eV photoluminescence band was found to be 9.7ms. These results were very similar to those for the 4.3 and 2.7eV photoluminescence bands which were observed in bulk silica glass of O-deficient type and were attributed to O vacancies. Due to changes in the photoluminescence intensity with film thickness, the buried oxide film was thought to contain O vacancy defects in high concentrations throughout its volume.

K.S.Seol, A.Ieki, Y.Ohki, H.Nishikawa, M.Tachimori: Journal of Applied Physics, 1996, 79[1], 412-6