| 摘要 |
PURPOSE:The whole of piping system is surrounded with an air-tight vessel and the vessel is filled with a high-purity gas inside so that only the high-purity gas is mixed in the pipings, even if there should be leaks in the piping system, thus preventing the contamination of the starting gases in the pipings with impurities. CONSTITUTION:The piping system for feeding the starting gases to the gas- phase crystal growth chamber is composed of inlets of starting gases 1, filteres 2, pressure controllers 3, flow rate controller 4, switching valves 5, joints 6 and the outlets of starting gases 8 and piping connecting them 7. The whole of the piping system is placed in the air-tight vessel 10. The vessel 10 is provided with the inlets and outlets of the starting gases as well as the inlet 11 and outlet 12, each of which is provided with a valve 13 and 14, on the wall. Thus, the vessel is filled with high-purity gas 15 and only high-purity gas is mixed in the starting gases, even if the piping system should have leaks, without contamination with impurities. |
