Patent · US Expired

Photodetector circuit

US6858912B2 · kind B2 · utility

36Cited by
20References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 2001
Grant dateFeb 22, 2005
Priority date
Expiry dateAug 8, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10F77/122
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A photodetector circuit incorporates an avalanche photodiode (APD) 300 produced by epitaxy on a CMOS substrate 302 with implanted n-well 304 and p-well 306. The n-well 304 has an implanted p+ guard ring 310 delimiting the APD 300. Within the guard ring 310 is an implanted n+ APD layer 312 upon which is deposited an epitaxial p+ APD layer 314, these layers forming the APD 300. The APD may be incorporated in an amplifier circuit 50 providing feedback to maintain constant bias voltage, and may include an SiGe absorption region to provide extended long wavelength response or lower avalanche voltage. Non-avalanche photodiodes may also be used.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.