Heterojunction bipolar transistor

US5332912A · kind A · utility

Assignee

• Kabushiki Kaisha Toshiba · JP

Inventors

• Tetsuro Nozu · Tokyo, JP
• Norio Iizuka · Stockholm, SE
• Junko Akagi · Yokohama, JP
• Torakiti Kobayashi · Yokohama, JP
• Masao Obara · Yokohama, JP

Key dates

• Filing date: Apr 23, 1993
• Grant date: Jul 26, 1994
• Expiry date: Apr 23, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D10/821

Abstract

A heterojunction bipolar transistor comprises n.sup.+ -type GaAs collector contact region, an n-type GaAs collector region, a p.sup.+ -type GaAs base region, an n-type AlGaAs emitter region, and an n.sup.+ -type InGaAs emitter contact region, all of which are formed on a semiinsulative GaAs substrate. A heterojunction is formed by the base region and the emitter region. The emitter region is formed in mesa shape by dry etching. Around this mesa, B.sup.+ ion-implanted high-resistance region is formed. The base-emitter Junction is isolated from the ion-implanted region. The heterojunction bipolar transistor therefore has little on-voltage changes.