UV ABSORPTION AND LUMINESCENCE IN SILICON OXYNITRIDE PREPARED BY HYDROGEN-FREE SPCVD-PROCESS

UV absorption and luminescence are investigated in bulk samples of sil icon oxynitride prepared by a hydrogen-free SPCVD-process (surface pla sma chemical vapour deposition). The UV absorption spectra, apart from the well-known silicon oxygen-deficient centre (Si-ODC), exhibit two unknown absorption bands with maxima at 5.77 and 4.54 eV and two unkno wn luminescence bands at 3.55 and 3.03 eV under laser excitation at 25 7 nm (4.83 eV). These new bands are supposed to be due to a nitrogen-m odified silicon oxygen-deficient centre.