Gas evolution studies for structural characterization of hexamethyldisilazane-based <i>a</i>-Si:C:N:H films

Abstract

Gas evolution and infrared-absorption studies on a-Si:C:N:H films deposited from hexamethyldisilazane vapor and nitrogen gas by a plasma process show that hydrogen at concentrations of more than 30 at. % is incorporated in the films. The hydrogen evolution spectra are similar to the spectra of a-Si:C:H films deposited from SiH4-CH4 mixtures, suggesting the presence of a continuous void network. At low plasma power a considerable amount of methyl groups is incorporated as detected by infrared absorption, leading to a hydrocarbon effusion in the 500–700 °C region. At high power the effusion of N2 at 600–800 °C indicates the incorporation of molecular nitrogen.