| 摘要 |
A semiconductor light-detecting element includes: a semiconductor substrate of a first conductivity type having a band gap energy, a first principal surface, and a second principal surface opposed to the first principal surface; a first semiconductor layer of the first conductivity type on the first principal surface and having a band gap energy smaller than the band gap energy of the semiconductor substrate; a second semiconductor layer of the first conductivity type on the first semiconductor layer; an area of a second conductivity type on a part of the second semiconductor layer; a first electrode connected to the second semiconductor layer; a second electrode connected to the area; and a low-reflection film on the second principal surface. The second principal surface is a light-detecting surface detecting incident light, and no substance or structure having a higher reflection factor, with respect to the incident light, than the low-reflection film, is located on the second principal surface. |
