| 摘要 |
PURPOSE:To prevent permeation of impurity and improve the film thickness distribution of a grown film, by surrounding a substrate to be grown with a gas curtain and forming a shower that has a dual tube structure to realize an uniform gas flow of a cylindrical type. CONSTITUTION:A shower 6 is installed to form a gas curtain around a substrate to be grown, 4, arranged in a growth chamber 1. The shower is made of a dual tube. An inner tube 6A is provided with a plurality of gas supplying ports and gas spouting ports. An outer tube 6D is provided with a gas spouting port 6E, whose spouting direction is changed from that of the gas spouting port 6B of the inner tube. An explanation is made about the growth of aluminum, for example. Hydrogen gas with a flow rate of about 2l/min is divided into four flows and sent into the inner tube 6A from four gas supplying ports 6C. The inner tube 6A spouts upward the hydrogen gas into the outer tube 6D. Here the gas pressure is decreased, the flow is made uniform, and the gas spouts downward to form a gas curtain.
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