JPS6462470A - Vapor synthesis method for high-pressure phase boron nitride - Google Patents

Abstract

PURPOSE:To continuously synthesize high-pressure phase BN in a vapor phase at a high film forming speed by projecting the hot plasma obtd. by light arc discharge from raw materials contg. a B atom and N atom as gas constituting components as a plasma jet onto a substrate and rapidly cooling the substrate. CONSTITUTION:The gas contg. the B atom such as the hydride of B such as B2H6 and the halide of B such as BCl3 and the gas which includes the N atom such as NH3 and N2 and is the raw material for BN are introduced 4. The gases are then heated to a high temp. of >=10,000 deg.C by a laser beam 2 condensed at the front end part of a condensing cone 12 and the high-temp. hot plasma having chemically high activity is obtd. by the light arc discharge. The gaseous raw material flow is made into the plasma jet 7 by the rapid thermal expansion of this time and is injected from a water-cooled plasma jet nozzle 6. In this plasma jet 7, the gaseous BN raw material in the gaseous raw material is decomposed and activated at a high density. A large amt. of the gaseous BN raw material is highly activated by the rapid cooling effect of the hot plasma when this jet collides against the substrate 8 kept at 500-1,200 deg.C. The high-pressure phase BN is thus synthesized in the vapor phase on the substrate 8 at the high film forming speed.