SILICON-NITRIDE FILMS DEPOSITED BY HG-PHOTOSENSITIZATION CHEMICAL VAPOR-DEPOSITION

Silicon nitride films have been deposited by the process of mercury-sensitized photochemical vapor deposition (photo-CVD), using a gaseous mixture of SiH4 and NH3 under 253.7 nm ultraviolet light irradiation. The main advantages of this technique are the low deposition temperature (100-400-degrees-C) and no radiation damage. Deposition rate of 8 nm/min and refractive index of about 2 were achieved. Infrared spectrum, SIMS spectrum and electrical properties of the films, including dielectric constant, flat-band voltage, breakdown field and mobile ion density were investigated.