Chemical Structure and Stability of Amorphous SiCxNy:H Films Prepared by ICP CVD Using Disilazanes

A comparative study of the environmental stability of amorphous hydrogenated silicon carbonitride SiCxNy:H–films is reported. The films are prepared at 200 °C by ICP CVD from a mixture of hexamethyldisilazane and tetramethyldisilazane with argon or nitrogen. After the preparation, changes in the chemical composition and chemical bonding of the films stored under ambient conditions in air are controlled by EDX, XPS, and FTIR spectroscopy. Changes in optical properties and wettability are estimated. The film prepared from a tetramethyldisilazane and argon mixture demonstrated insignificant changes, whereas other films exhibited evolution of their chemical structure: the silazane fragments were lost, and significant amount of oxygen was incorporated mainly in the form of siloxane bonds.