Infrared-radiation detector device

US4894526A · kind A · utility

Assignee

• American Telephone and Telegraph Company, AT&T Bell Laboratories · US

Inventors

• Clyde George Bethea · Willingboro, US
• Kwong-Kit Choi · Brookeville, US
• Barry Levine · Livingston, US
• Roger Malik · Summit, US
• John Walker · Westfield, US

Key dates

• Filing date: Sep 15, 1987
• Grant date: Jan 16, 1990
• Expiry date: Sep 15, 2007

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F77/146
• WIPO field: Micro-structural and nano-technology
• WIPO sector: Chemistry

Abstract

A narrow-bandwidth, high-speed infrared radiation detector is based on tunneling of photo-excited electrons out of quantum wells. Infrared radiation incident on a superlattice of doped quantum wells gives rise to intersubband resonance radiation which excites electrons from the ground state into an excited state. A photocurrent results from excited electrons tunneling out of quantum wells. Conveniently, Group III-V materials can be used in device manufacture. Preferably, quantum well potential barriers are shaped so as to facilitate resonant tunneling of photocurrents as compared with dark current. Preferred device operation is at elevated bias voltage, giving rise to enhancement of photocurrent by a quantum-well-avalanche effect.