Effects of nitrogen fraction on the structure of amorphous silicon-carbon-nitrogen alloys

The silicon-carbon-nitrogen (SiCN) alloys prepared by DC magnetron sputtering at room temperature with graphite and silicon targets at different nitrogen partial pressure were systematically investigated. It was found that a high nitrogen fraction in the nitrogen-argon gaseous mixture enhances the incorporation of C and N, but reduces the incorporation of Si. The Si-C, Si-N, Si-Si, C-N, C = N, C equivalent toN, C-O, C-C, C = C and N-H bonds can all be observed in the alloys. The C-N, C = C and C = N bonds dominate the structure of the alloys, while the Si-C, Si-Si and Si-N bonds are less significant. As the N-2/(N-2 + Ar) ratio increases, the densities of the Si-C, Si-N and C-N bonds decrease, while those of the C=N, C-C, C=C and C equivalent toN bonds increase. In addition, the deposition rate is found to monotonically increase with the nitrogen partial pressure, probably due to the enhanced incorporation of nitrogen and carbon. (C) 2000 Published by Elsevier Science B.V. All rights reserved.