| 摘要 |
PROBLEM TO BE SOLVED: To output a highly-accurate photocurrent.SOLUTION: A phototransistor 10 comprises a first emitter region 12, a first base region 14 at least a part of which is exposed to a light reception side L, and a first collector region 25, in this order from the light reception side L in a depth direction Z. The first collector region 25 has a second collector region 22, and a third collector region 24 provided so as to be in contact with a downstream side in a depth direction Z, of the second collector region 22, and having a resistance lower than that of the second collector region 22. The phototransistor 10 comprises a first region 18 provided outside of the first base region 14 on a surface of the light reception side L at an interval from the first base region 14, and having a reverse conductivity type to the first collector region 25. |
