| 摘要 |
PURPOSE:To realize a semiconductor photodetector excellent in both dark current and high-speed response characteristics by a method wherein the formation is prevented of a p-n junction approximating a single-side junction outside the region on top of a mesa and the circumference of a p-n junction approximating such a single-side junction is covered by a p-n junction approximating a slant-type junction. CONSTITUTION:An n-InGaAsP layer (first semiconductor layer) 14 is formed, which is followed by the formation of an n-InP layer (second semiconductor layer) 15. Most of the n-InP layer 15 is removed, whereby a mesa is selectively retained. On top of the mesa, an n<-> - InP layer (third semiconductor layer) 16 is formed. An SiO2 film is formed and then the region along the circumfer ence of the n-InP layer 15 is concentrically removed. After the removal of the photoresist.SiO2 on the wafer, heat treatment is accomplished for the forma tion of a p-InP region 17. This results in the formation of a p-n junction 18 approximating a slant-type junction. Next, an insulating film 21 is formed in the same way and the p-InP region 17 is removed selectively of its internal circumference for the formation of a p<+> - InP region 19. The p<+> - n junction 20 thus formed approximates a single-side junction. |
