| 摘要 |
PURPOSE:To prevent the decrease in photo taking out efficiency from an upper surface, and realize a Si-doped high efficiency GaAs diode emitting infrared rays, by forming continuously, on a P-type epitaxial layer, a P-type epitaxial layer whose impurity density is lower than that of the former epitaxial layer. CONSTITUTION:In the case where an N-type epitaxial layer and a P-type epitaxial layer are continuously formed on an N-type GaAs substrate, ammonia gas NH3 is introduced as an atmospheric gas during the P-type epitaxy. As the result of introducing the NH3 gas, on a P-type epitaxial layer, a P-type epitaxial layer whose impurity density is smaller than that of the former layer is continuously formed. Thereby, the impurity density and the absoption coefficient of the surface of the P-type epitaxial layer can be made small, so that the decrease of photo taking out efficiency due to the characteristic of the epitaxial layer wherein the impurity density and the absorption coefficient become layer can be prevented. |
