| 摘要 |
PROBLEM TO BE SOLVED: To obtain a CVD-SiC molded body free from warpage and cracking by forming a silicon carbide layer on a substrate of a porous silicon carbide sintered body having a surface layer of a carbon layer or a silicon layer by a CVD method, thereafter removing the surface layer and separating the substrate. SOLUTION: A substrate 10 is composed of a material same as that of a CVD-SiC molded body 20 whose thermal expansion coefficient is almost equal to that of the one. The whole of the surface of the substrate 10 is, e.g. coated with a slurrylike carbon adhesive composed of high purity carbon powder, which is dried to form a surface layer 15 of carbon. Next, it is set to a vacuum CVD furnace, SiCl4 and CH4 are used as a gaseous starting material, H2 is used as carrier gas, and the molded body 20 is formed under the conditions, e.g. of 100 Torr×1300 deg.C×15 hr. Successively, the outer circumference thereof is ground till the substrate 10 is exposed. Moreover, it is charged to an oxygen atmosphere of 1200 deg.C and is let to alone, and the surface layer 15 is baked away to remove, by which the substrate 10 and the molded body 20 can easily be separated.
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