The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 07, 2009
Filed:
Feb. 03, 2005
Tadao Ishibashi, Tokyo, JP;
Seigo Ando, Tokyo, JP;
Yukihiro Hirota, Tokyo, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
NTT Electronics Corporation, Tokyo, JP;
Abstract
An ultra high speed APD capable of realizing reduction in an operating voltage and quantum efficiency enhancement at the same time is provided. Under operating conditions APD, a doping concentration distribution of each light absorbing layer is determined so that a p-type light absorbing layer () maintains a p-type neutrality except a part thereof, and a low concentration light absorbing layer () is depleted. Moreover, a ratio between a layer thickness Wof the p-type light absorbing layer () and a layer thickness Wof the low concentration light absorbing layer () is determined so that W>0.3 μm and a delay time of an element response accompanying a transit of carriers generated in the light absorbing layer by light absorption takes on a local minimum under a condition that a layer thickness W(=W+W) of the light absorbing layer is constant.