| 摘要 |
PURPOSE:To obtain the epitaxial growth layer having the predetermined impurity concentration when N<++>, N<+> or N<-> type layers are laminated on a compound semiconductor substrate and are grown by providing an impurity doping system separated from a crystal growth system which is a carrier gas includes a material gas for crystal-growth and a vapor phase etching system for supplying an etching gas for a reaction chamber. CONSTITUTION:Gas introducing pipes to be connected to a tube reactor are arranged with being divided into three systems 1, 2 and 4. In the introducing pipes 1 and 2, H2 gas flows and in the pipe 4', SiH4 or H2S gas flows through valves V4, V5 and V6, V1 and V2, and further V3 respectively. V1 and V2 are connected to an arsenic trichloride tank 6. Also V4 and V5 are connected to an arsenic trichloride tank 5 and O2 gas is supplied for V6 through the pipe 3. By this constitution, the introducing pipe 2 and the tank 6 compose a vapor phase etching system and the pipe 1 and the tank 5 composed a crystal growth system. Further, the pipe 4' composes an impurity doping system. Thus inclusion of impurities is restrained by separating arsenic trichloride which corrodes the introducing pipes by different systems. |
