| 摘要 |
PURPOSE:To prepare the titled silicon nitride having high mechanical strength and a few micro-crack, by encircling the surroundings of fluxes of gas stream for the source for precipitating N to be blown to a hot substrate with a gas for the source for precipitating S, depositing the decomposition product in a gaseous phase of both gases on the substrate. CONSTITUTION:The base 2 is heated in a container at about 1,000-1,900 deg.C. A gas such as NH3, etc. for the source for precipitating N is blown from the inner tube 101 of combined tubes to the substrate 2, and a gas such as SiCl4, etc. for the source for precipitating S from the outer tube 102 to it using H2 as a carrier gas. The surroundings of the gas flow of NH3 is encircled with a gas consisting of H2 and SiCl4 vapor, so that the gaseous phase decomposition reaction between NH3 gas and SiCl4 vapor takes place on the substrate 2 or in the vicinity of it. Consequently, the formed finely granular crystalline Si3N4 is deposited on the substrate 2, to give finely granular crystalline silicon nitride having high hardness, high purity and high mechanical strength. |
