| 摘要 |
PURPOSE:To sharply improve a solar cell in photoelectric conversion efficiency by a method wherein a GaP buffer layer is interposed between a single crystal Si solar cell and a first solar cell formed of a GaAsP compound semiconductor thin film whose forbidden bandwidth lies in a specific range of eV. CONSTITUTION:A single crystal Si solar cell 8 is composed of a P-type Si layer 1 and an N-type Si layer 2. A GaP buffer layer 3 is provided onto the cell 8. Moreover, a first solar cell 9 composed of a P-type GaAs1-xPx layer 4 and an N-type GaAs1-xPx layer 5 is provided onto the buffer layer 3. The cell 9 is formed of a GaAsP compound semiconductor thin film whose forbidden bandwidth is 1.57-1.73eV, and the buffer layer 3 is interposed between the cells 8 and 9. By this setup, a solar cell of this design can be sharply enhanced in photoelectric conversion efficiency. |
