Electron cyclotron resonance chemical vapor deposition of silicon oxynitrides using tris(dimethylamino)silane

A new compound, tris(dimethylamino)silane was used as an organosilicon source for the deposition of silicon oxynitride thin films. The depositions were carried out at low substrate temperatures (<150 °C) in an electron cyclotron resonance plasma enhanced chemical vapor deposition reactor. Films with compositions varying from Si3N4 to SiO2 were deposited on silicon substrates by varying the N2/O2 flow ratio to the plasma chamber. In situ ellipsometry measurements of the film optical index were well correlated with film composition. Auger electron spectroscopy showed that only low levels of carbon (<3 at. %) were present, while Fourier transform infrared spectroscopy showed low levels of bonded hydrogen. The deposition rate of high quality Si3N4 was as high as 220 Å/min.