| 摘要 |
PURPOSE:To improve the light-emitting efficiency of a tandem-type solar cell by a method wherein a cathode electrode is formed in a region other than the region opposite to an effective photodetection region on a photodetection face of a semiconductor layer. CONSTITUTION:A semiconductor layer 2 composed of p-type GaAs is formed on an n-type GaAs substrate 1; a p-n junction 3 is formed between the substrate 1 and the layer 2. A collector 6 of a pattern combining concentric circles with radial lines is formed inside an effective photodetection region 5 on a photodetection face; a common electrode 7 connected to the electrode 6 is formed around it; an anode electrode 8 is formed of the electrodes 6, 7. A cathode electrode 28 having a circular hole 27 whose size is neraly the same as that of the photodetection region 5 is formed on the rear of the substrate 1. In this solar cell, a component of sunlight which could not be absorbed by the semiconductor layer 2 and the substrate 1 out of sunlight which is incident on the photodetection region 5 is taken out by the electrode 28 on the rear without being shielded. When a tandem-type solar cell is constituted, a photovoltaic force of a second solar cell arranged at the lower side is increased. |
