| 摘要 |
PURPOSE:To grow a good-quality and large-diameter compd. semiconductor crystal with good reproducibility and in good yield by controlling the cooling so that the temp. gradient at the solid-liq. interface and the cooling rate are made almost constant while keeping the conditions where the temp. distribution is raised from the center of the melt surface toward the outside in the radial direction and the temp. is progressively elevated toward the lower part. CONSTITUTION:An ampule 1 contg. the raw material 2 for a compd. semiconductor is held at a specified position in a heating furnace 3 split in the vertical direction. The raw material 2 in the ampule 1 is then heated and completely melted, and the temps. at the upper part 7 of the ampule 1, the intermediate part 8, and the lower end 9 are continuously measured. The electric power to be supplied to the furnace 3 at each stage is adjusted based on the measured temps. of the ampule 1. By this method, the temp. at the center of the melt surface is made the lowest in the ampule 1, and the temp. is progressively increased toward the outside in the radial direction. The cooling is controlled so that the temp. gradient at the solid-liq. interface and cooling rate are made almost constant in the specified range while keeping the conditions where the temp. is progressively lowered toward the lower part of the melt, and a single crystal is grown from the melt surface toward the lower part.
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