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:
Oct. 03, 2017
Filed:
Jun. 13, 2014
Mengyuan Huang, Beijing, CN;
Pengfei Cai, Beijing, CN;
Dong Pan, Andover, MA (US);
Liangbo Wang, Beijing, CN;
Su LI, Beijing, CN;
Tuo Shi, Beijing, CN;
Tzung I Su, Zhongli, TW;
Wang Chen, Beijing, CN;
Ching-yin Hong, Lexington, MA (US);
Mengyuan Huang, Beijing, CN;
Pengfei Cai, Beijing, CN;
Dong Pan, Andover, MA (US);
Liangbo Wang, Beijing, CN;
Su Li, Beijing, CN;
Tuo Shi, Beijing, CN;
Tzung I Su, Zhongli, TW;
Wang Chen, Beijing, CN;
Ching-yin Hong, Lexington, MA (US);
SIFOTONICS TECHNOLOGIES CO., LTD., Woburn, MA (US);
Abstract
Avalanche photodiodes (APDs) having at least one top stressor layer disposed on a germanium (Ge) absorption layer are described herein. The top stressor layer can increase the tensile strain of the Ge absorption layer, thus extending the absorption of APDs to longer wavelengths beyond 1550 nm. In one embodiment, the top stressor layer has a four-layer structure, including an amorphous silicon (Si) layer disposed on the Ge absorption layer; a first silicon dioxide (SiO) layer disposed on the amorphous Si layer, a silicon nitride (SiN) layer disposed on the first SiOlayer, and a second SiOlayer disposed on the SiN layer. The Ge absorption layer can be further doped by p-type dopants. The doping concentration of p-type dopants is controlled such that a graded doping profile is formed within the Ge absorption layer to decrease the dark currents in APDs.