| 摘要 |
PURPOSE:To improve light transmissivity of a substrate without decreasing the thickness of the substrate by setting carrier concentration of an InP monocrystalline substrate in a particular range and using the substrate having no displacement. CONSTITUTION:An InP monocrystalline ingot is manufactured by VCZ process, and this is sliced to fabricate an n<+> type InP monocrystalline substrate 1, and carrier concentration thereof is made to be 1X10<17>-3X10<18>cm<-3> and dislocation density (EPD) thereof is suppressed to be not larger than 500<1>/cm<2>. An n<-> type InGaAs light absorbing layer 3 is formed on this substrate by gas-phase growing process. In the wafer thus obtained, the carrier concentration is lower than in the past, the light transmissivity of the substrate is increased, and the light absorption by the substrate is reduced, so that the light receiving sensitivity and the light emitting efficiency of the semiconductor device can be improved. Further, because the InP monocrystalline substrate has no displacement, the light receiving sensitivity, etc., can be improved without lowering the characteristics for the dark current, etc. |
