| 摘要 |
PROBLEM TO BE SOLVED: To provide a solar cell which can increase photoelectric conversion efficiency in a structure having a quantum dot layer on a semiconductor substrate.SOLUTION: In a solar cell including on a principal plane 3 of a semiconductor substrate 1 a quantum dot layer 5 which is composed of a plurality of quantum dots 5a placed one on top of another and a matrix 5b containing the quantum dots 5a therein, the quantum dots 5 are spherical in shape, a variation in the diameter of which is within 10%. Therefore, the energy levels of intermediate bands Bformed by adjacent quantum dots 5a in the quantum dot layer 5 become almost the same, so that as wave functions between the quantum dots 5a become easier to overlap, so do carriers such as electrons generated in the quantum dots 5a become easier to tunnel between the quantum dots 5a. As a result, carrier transport efficiency can be raised. |
