In order to develop a method for the detection of low-level O in thin crystals by using photoluminescence techniques, a radiative C-O center (C center: 0.79eV) was formed in Si crystals by the introduction of C via ion implantation. The photoluminescence intensity of the C center of the implanted sample was significantly increased by annealing the sample at 1000C, followed by electron irradiation. It was expected to be possible to detect an O concentration of less than 1015/cm3 in layers which were thinner than 1.

M.Nakamura, A.S.Byrne, E.Kitamura, T.Suzuki, S.Nagai, H.Sunaga, Y.Aoki, H.Naramoto: Journal of Applied Physics, 1995, 78[7], 4407-10