Photodetector with absorbing region having resonant periodic absorption between reflectors

US5389797A · kind A · utility

Assignee

• The United States of America, as represented by Department of Energy · US

Inventors

• Robert P. Bryan · Albuquerque, US
• Gregory R. Olbright · Boulder, US
• Thomas M. Brennan · San Francisco, US
• Jeffrey Y. Tsao · Albuquerque, US

Key dates

• Filing date: Feb 24, 1993
• Grant date: Feb 14, 1995
• Expiry date: Feb 24, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F77/413

Abstract

A photodetector that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs. Individual ones of the InGaAs layers are spaced apart from one another by a GaAs barrier layer.