| 摘要 |
PURPOSE:To obtain a solar cell made of a compound semiconductor having a structure of high performance GaAs cell/Si substrate and the like, by making the impurity concentration of a silicon substrate to be approximately 1X1016 cm<-3> or less, and making it possible to grow the crystal of a high quality GaAs layer by decreasing the impurity concentration of the Si substrate. CONSTITUTION:Single crystal compound semiconductor layers 2, 3 and 4 are formed on an N-type silicon substrate 1 directly or with layer comprising specified materials being held inbetween. In this compound semiconductor solar cell, the impurity concentration of the silicon substrate 1 is made to be approximately 1X10<16> cm<-3>. The efficiency of the GaAs cells 2, 3 and 4 and the Si substrate depends on the resistance of the Si substrate 1. When the thickness of the Si substrate 1 is -300 mum or less, the resistivity of the Si substrate satisfying <=10 OMEGAcm is sufficient. The resistivity of the Si substrate depends on the doping amount of the impurities. When the impurity concentration of the Si substrate 1 is decreased, the dislocation density in GaAs is decreased, and the high efficiency GaAs cell/Si substrate is achieved. |
