SEMICONDUCTOR THIN FILM VAPOR PHASE GROWTH APPARATUS

PURPOSE:To form a uniform thin film by a method wherein a truncated cone shape reaction tube and an inverse pyramid frustum shape susceptor are arranged in such a manner that the gap between the reaction tube and the susceptor becomes narrower toward the upward direction and the substrate is heated by making raw material gas flow from the bottom to the top in the reaction tube. CONSTITUTION:A gas inlet 2 and a gas exhaust 3 are provided to the bottom and the top of the reaction tube 1 respctively. A carbon susceptor 4 with an inverse pyramid frustum shape which is expanded toward the upward direction is contained in the reaction tube 1 coaxially so that the gap between the reaction tube 1 and the susceptor 4 is made narrower toward the upward direction. The susceptor 4 is rotated to the direction of an arrow by a rotary shaft 10 provided to the top. Substrates 5 are attached to the side planes of the susceptor 4 flatly. Raw material gas and carrier gas are made flow from the bottom to the top of the reaction tube 1 as shown by arrows. The substrates 5 are heated to the prescribed temperature and the raw material gas near the substrates is subjected to the thermal decomposition and a semiconductor thin film is made grow on the substrate 5.