| 摘要 |
PURPOSE:To obtain a high collector output for a power phototransistor by forming comblike base region on a semiconductor substrate, forming a comblike emitter region therein, as a power phototransistor, and forming an impurity high density region having the same conductivity type as the base region and higher density than this between the emitter regions. CONSTITUTION:The comblike P type base region 11 is diffused in the region 10b of a collector semiconductor substrate 10 having N type region 10b in the upper portion and N<+> type region 10a in the lower part, and the comblike N<+> type emitter region 12 is similarly formed therein. Then, an insulating film 14 is covered on the entire surface, a window is perforated thereat, a base pickup electrode 15 is mounted at the region 11, and an emitter pickup electrode 16 is mounted at the region 12, as a planar type power phototransistor. With this configuration, a shallow P<+> type region 13 is added to the surface layer of the region 10b between the regions 12. Thus, the incident light amount is increased, the quantum efficiency is also enhanced, thereby increasing the collector output. |
