| 摘要 |
PURPOSE:To enable confirmation of a wafer placed and determination of the position of the wafer due to breaking of an optical pass or not by receiving light generated from one single crystal sapphire with the other single crystal sapphire, a pair of the sapphires being provided on the top side and the bottom side of the wafer. CONSTITUTION:A plasma gas supply hole 14, a chamber 15 for generating plasma and plural plasma ejection nozzles 16 are provided at the top 12 of a reaction tube 11 and an exhaust nozzle 17, a susceptor 18 for mounting a wafer 8 and a stroke mechanism 19 for moving up and down a table 13 are provided on the table 13. A single crystal sapphire projector 20 is provided on the top 12 and a single crystal sapphire optical receiver 21 is provided on the table 13. Single crystal sapphires 22, 23, focusing lenses 24, 25 and optical fibers 26, 27 form an optical pass. The single crystal sapphire can pass light only in the optical axis direction and cannot pass light from the other directions so if a plasma luminescence is generated, the correct or eccentric position of the wafer can be detected due to the breaking of the optical pass. |
