Evidence for the formation of SiON glasses

Novel glasses within the Si-O-N system were synthesized by melting mixtures of crystalline alpha-SiO(2) and alpha-Si(3)N(4) in the range from 2.9 to 24 at.% nitrogen. X-ray diffraction (XRD) and Fourier transformation infrared spectroscopy (FT-IR) measurements indicate the formation of ternary phases in an amorphous state. The incorporation of nitrogen into the network structure was proven by (29)Si magic angle spinning nuclear magnetic resonance (MAS-NMR) and Si K-X-ray absorption near edge structure spectroscopic studies which both show. independently. the presence of mixed SiO(4-x)N(x) tetrahedra (x = 0, 1, 2, 3, 4). The relative frequency of these units as derived from the deconvolution of (29)Si-MAS-NMR spectra is in agreement with a random distribution of nitrogen within the network structure. (C) 1998 Elsevier Science B.V.