| 摘要 |
PURPOSE:To obtain the photodetecting device having excellent characteristics of reverse pressure resistance and dark current by a method wherein on a single- conduction-type semiconductor layer having a large photoabsorption coefficient and transparency is grown another single-conduction-type semiconductor layer having also transparency but higher density of impurity than the former and there Schottky junction is provided. CONSTITUTION:On a transparent N<-> type Ge substrate 1 having a large photoabsorption coefficient of 10<4>cm<-1> or more in relation to a light with a wavelength of 1.0-1.5mum, a grid constant of 5.65748Angstrom and the impurity density of 1.5X 10<14>cm<-3> is grown a GaAs layer 3 of N type likewise which is transparent to a light having a wavelength of about 0.9mum or more and which has a grid constant of 5.6534Angstrom close in value to that of Ge and the impurity density of 5X10<15>cm<-3> higher in one column than that of the substrate 1. On the layer 3 are provided metal electrodes 5 and 6, wherein Schottky junctions 7 and 8 are caused respectively and which are connected in series with a power source 10 and a load resistance 9. By this constitution, when a light 14 is applied on the surface of the layer 3, it is absorbed in a region 15 across a line of electric force 11 under heterojunction 2 and thus a photoelectric current corresponding to the incident light is supplied to a load 9. |
