Influence of deposition condition and hydrogen on amorphous-to-polycrystalline SiCN films

Synthesis of SIGN thin films on mirror-polished Si(100) substrates has been achieved by performing a bias-assisted hot filament chemical vapor deposit ion. High purity nitrogen, methane, and hydrogen were used as reactant gase s. Incorporated Si element in the films totally came from the Si surface of the substrate. Scanning electron microscopy showed two categories of morph ologies of the films according to the introduction of hydrogen. Energy-disp ersive X-ray analysis and Auger electron spectroscopy depth profiling were used to measure the chemical composition of the samples. With no hydrogen a pplied, the film was found to be a nitride layer over the Si substrate with some nanosize columnal silicon-containing C-N crystals embedded. With hydr ogen added, the film was uniformly composed of smaller SiCN particles. On b oth conditions, the overall carbon content was rather limited. X-ray photoe lectron spectroscopy revealed the chemical environment of C, N, and Si atom s in the samples. The effect of methane flow ratio and substrate temperatur e were investigated on the conditions without hydrogen flow. The effects of hydrogen flow ratio on the films were also studied. (C) 1999 Elsevier Scie nce S.A. All rights reserved.