Formation of ultrathin Si N layers on silicon utilizing PECVD

Abstract We exposed crystalline Si (C-Si) substrates to a NH 3 plasma by the method of plasma enhanced chemical vapor deposition (PECVD) and the Si substrates were nitrided at a nitridation temperature, T n , between 300 and 600 °C. The nitrided layers were grown directly on n-type C-Si substrates with high resistivity for measurements of electron resonance (ESR) and Fourier transform infrared (FTIR) absorption. The intensity of the N–H IR bending band increased with increasing T n up to 450 °C, and then decreased again with a further increasing in T n . We found a strong correlation between the change in the ESR spin density, N s , and that in the N–H bending intensity, which was obtained from the spectral intensity at around 1200 cm −1 . Furthermore, incorporation of N atoms in amorphous Si x N y layers may improve the structural property at T n = 450 °C for various insulating applications. In addition, we found that the atomic densities and/or composition of a-Si x N y may decrease the BHF etch rate.