Plasma enhanced chemical vapor deposition of Si-N-C-H films from environmentally benign organosilanes

The environmentally benign precursors diethylsilane (DES) and di-t-butylsilane were used with NH₃ to synthesize hydrogenated silicon carbonitride films by plasma enhanced chemical vapor deposition. The growth kinetics and film properties were examined as a function of deposition temperature, pressure, and NH₃/organosilane ratio. The growth rate was observed to decrease with higher temperature and higher NH₃/organosilane ratio while increasing with higher total pressure. Values of index of refraction, stress, hardness, and Young's modulus were measured as a function of processing variables and related to film density and resulting film compositions. Oxidation of the films was noted to occur at low deposition temperatures, low NH₃/ organosilane ratios, and high pressures. Carbon was present in all deposits and decreased slightly with higher NH₃/organosilane flow ratios.