| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a thin film semiconductor device wherein the light absorption efficiency and the photoelectric conversion efficiency can be raised in a single crystal Si thin film solar cell, etc. SOLUTION: A transparent thin plastic film base 14 is disposed on the opposite surface of a solar cell element 10 to a plastic film base 12. A diffraction grating 15 disposed between the plastic film base 14 and the cell element 10 has a reflection type brazed grating structure made of a conductive material such as Al. An incident light is diffracted by the grating 15 and returns to the cell element 10. If this diffraction angle exceeds a certain value, the angle making with a normal to the solar cell increases enough to totally reflect it on the top surface of an Si thin film layer (solar cell element 10) or the surface of the transparent plastic film base 12 and it returns to the cell element 10. Such process of returning to the cell element 10 is repeated to confine the light in the interior of the cell element 10.</p> |
