JPS6428295A - Vapor growth process and apparatus therefor - Google Patents

Abstract

PURPOSE:To form a high-quality Ga-P compound thin film free from anti-phase on a large-sized substrate, by passing a PH3-containing H2 gas on a substrate in a specific reaction tube, introducing a GaCl-containing H2 gas through another flow channel into the reaction tube and transferring the joining part of both streams on the surface of the substrate at a prescribed speed. CONSTITUTION:A reaction tube 22 made of a quartz glass has a double-tube structure together with a group III element raw material chamber 18A made of a quartz glass inserted into the reaction tube. A quartz boat holding a group III element 18 (e.g. Ga) is placed in the raw material chamber 18A, the outer circumference of the reaction tube 22 is encircled with heating electric furnaces 17A-17C and a substrate-holding tool 14 holding a substrate 15 is inserted into the reaction tube 22 in such a manner as to be movable via a rod 14A and a magnetic coupling 13, 13A, etc. H2 gas is introduced into the reaction tube 22 through gas-inlet ports 19A, 20A until the air in the reaction tube 22 is completely substituted with H2. The tube is heated at about 1,000 deg.C, the electric furnaces 17A, B and the furnace 17C are adjusted to 350-450 deg.C and 650-900 deg.C, respectively and a PH3-containing H2 gas 20 and HCl-containing H2 gas 19 are introduced through the inlet ports 20A and 19A, respectively. The GaCl gas stream and PH3 gas stream produced by the reaction are joined with each other at the front end 16A of a barrier wall 16. When the flow rate is stabilized, the substrate 15 is transferred in right or left direction at a constant speed to uniformly form a GaP thin film on the substrate 15.