Contribution of multiple emitting centers to luminescence from Si/SiO2 multilayers with step by step thermal annealing

a-Si:FVSiO2 multilayers have been prepared by alternating changing plasma enhanced chemical vapor deposition of a-Si:H layers and in situ plasma oxidation process. A series of step by step thermal annealing from 350 to 1100 degreesC were employed as the post treating procedure. Fourier Transform Infrared (FTIR) and photoluminescence (PL) spectra were measured as a function of annealing temperature. A broad red photoluminescence band ranged from 550-720 nm arises as the annealing temperature increases and vanishes after annealing above 650 degreesC. A strong luminescence peak at 750 nm is observed for annealing temperature above 950 degreesC. It is suggested that various luminescence centers contribute to the PL bands simultaneously, which can be related to the different bonding configurations of H and O during the annealing process. (C) 2004 Elsevier Ltd. All rights reserved.