Patent · US Expired

Semiconductor photo-detector having a two-stepped impurity profile

US4949144A · kind A · utility

22Cited by
7References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 1, 1988
Grant dateAug 14, 1990
Priority date
Expiry dateSep 1, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10F30/2255
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A semiconductor photo-detector having a two-stepped impurity profile comprises a semiconductor substrate, a light absorption layer of a first conductivity type formed on a semiconductor substrate, a multiplication layer of a first conductivity type formed on the light absorption layer to multiply a photocurrent, a semiconductor region of a second conductivity type formed on the multiplication layer and constituting an abrupt pn junction with the multiplication layer, and a guard ring area of a second conductivity type formed around a periphery of the semiconductor region, whereby the carrier concentration profile of the guard ring region is sharp at its surface and flat below that surface.

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