| 摘要 |
PROBLEM TO BE SOLVED: To prevent the inner wall of a reaction tube from contamination by surrounding a heat processing part with a shield pipe made of a specific material in specific structure, making uniform the temp. of a specimen, and keeping the atmosphere at a high purity. SOLUTION: A reaction tube 2 made of quartz accommodates a heat processing part 1 consisting of susceptor made of graphite, and a specimen 18 is heated at 1500-2000 deg.C with a high frequency current flowing through a heater coil 4 wound round the periphery, and thereby crystal growth of silicon carbide (SiC) and other necessary heat treatment are conducted. A heat shield pipe 13 is made from SiC of high purity, and therewith the heat processing part 1 is surrounded contactlessly. The shield pipe 13, at least its inside circumferential surface, is covered with a SiC film of 50-200μm with high purity and high density by means of chemical evaporation, and thereby emission of the impurities is prevented. In cooperation with an upper and a lower situated shield plate 16 and 17, the shield pipe 13 works as a reflector to reflect the emitted heat from the heat processing part 1 and prevents active gas generated from the specimen 18 from directly touching the reaction tube 2.
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