JPS5648237A - Evacuated gaseous phase reactor - Google Patents

Abstract

PURPOSE: To secure a uniform distribution of concentration for the material component in a reaction tube and thus obtain a uniform thickness for the grown film, by increasing the flow speed at the area near the surface of the substrate for the material gas within the reaction tube of the evacuated GVD method.

CONSTITUTION: The epitaxial growth of the semiconductor crystal onto the surface of the semiconductor substrate, the growth of the polycrystalline silicon layer or the gaseous phase reaction method (CVD method) for formation of the SiO₂ layer is carried out within the reaction tube 21. The reaction material gas is supplied through the introducing mouth 25 in case when the tube 21 is of vertical type and then exhausted and pressure-reduced through the discharge mouth 26 to be heated up with the resistor 22. Here the outer wall 27 is provided to give a limitation to the gas flow path as if it enclosed the susceptor 23, and thus the reaction gas flows the area enclosed by both the outer wall and the susceptor not to expand over the whole part of the bell-jar. As a result, the reaction progresses on the surface of the substrate to be treated and put on the susceptor 23 to ensure a uniform growing speed over the entire surface of the substrate. Thus a uniform thickness of film and uniform distribution of concentration can be obtained.

COPYRIGHT: (C)1981,JPO&Japio