| 摘要 |
PROBLEM TO BE SOLVED: To provide a forward mesa photodetector which suppresses a dark current near the side face of a mesa and which can improve photodetecting sensitivity and reliability of the element. SOLUTION: The forward mesa photodetector 12 includes a buffer layer 2, an optical absorption layer 3, a field alleviation layer 4, and a multiplication layer 5 laminated on a semiconductor substrate. In the forward mesa photodetector 12, the multiplication layer 5 includes a contact region 6 doped with an impurity to ohmic contact with a central region except the vicinity of the side face of the forward mesa structure in a region near the most separate surface of the surface opposed most separately from the semiconductor substrate 1, and a deep guard ring 7 doped with the impurity in a lower concentration than the impurity concentration of the contact region 6 in the region near the side face of the forward mesa structure, and has a configuration that the deep guard ring 7 extends to the field alleviation layer 4 side deeper than the most separate surface of the multiplication layer 5 as compared with the contact region 6. COPYRIGHT: (C)2006,JPO&NCIPI
|
