OUTER TUBE MADE OF SILICON CARBIDE AND SEMICONDUCTOR HEAT-TREATMENT SYSTEM TO IMPROVE ENDURANCE AND MINIMIZE CONTAMINATION CAUSED BY PARTICLES

摘要

PURPOSE: An outer tube made of silicon carbide is provided to deal with an increased diameter without forming a protrusion for supporting a flange in a base by shortening an interval between the lower end of a heater and the base and by increasing a wafer throughput in a semiconductor heat-treatment system. CONSTITUTION: An outer tube(72) is made of silicon carbide, having a closed upper part and an open lower part. The outer tube is of a taper shape in which the diameter of the outer tube becomes larger as it goes to the lower end of the outer tube. A flange(72c) is formed in the outer circumference of the lower part. ta/D1 is from 0.0067 to 0.025. taxD1 is from 600 to 4000 square millimeters. (DF2-DF1)xtc/(D1xta) is from 0.1 to 0.7. L1/L2 is from 1 to 10. The outer tube has a thickness of ta millimeter and an inner diameter of D1 millimeter. The flange has a thickness of tc millimeter and an inner diameter of DF1 millimeter. The height of the taper part has an extension length of L1 millimeter and L2 millimeter.