STRUCTURAL AND OPTICAL PROPERTIES STUDIES OF SPUTTERED a-SiCN THIN FILMS

Amorphous silicon carbonitride (a-SiC(x)N(y)) thin films were deposited by reactive sputtering from SiC target and N(2)/Ar mixtures. Their structural study was carried out by mean of RBS, FTIR, Raman and electron spin resonance analysis. The optical properties were determined by UV-visible spectroscopy. The fact to introduce different amounts of nitrogen with argon in the gas phase induced structural changes which are visible since 5% of N(2). For more than 30% of nitrogen in the gas mixture, a N-saturated Si-C-N film were formed. The increase of nitrogen gas concentration induced the appearance of C-C sp(2) character, an increase of the C=N and dangling bonds densities. All these structural variations leaded to an increase of optical band gap from 1.75 to 2.35 eV.