Field-effect transistor having a delta-doped ohmic contact

US4780748A · kind A · utility

Assignee

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

Inventors

• John E. Cunningham · San Diego, US
• Erdmann F. Schubert · Hazlet, US
• Won-Tien Tsang · Holmdel, US

Key dates

• Filing date: Jun 6, 1986
• Grant date: Oct 25, 1988
• Expiry date: Jun 6, 2006

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/62
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A field-effect transistor is created on a GaAs semi-insulating substrate using molecular beam epitaxy by fabricating a delta-doped monolayer with a silicon dopant between two undoped GaAs layers grown over the semi-insulating substrate. A plurality of delta-doped monolayers are grown over the surface of the upper undoped layer interleaved with layers of GaAs having a thickness equal to or less than the tunneling width of electrons in GaAs. A channel is etched through the plurality of delta-doped monolayers to permit a gate electrode to contact the upper undoped GaAs layer. Source and drain electrodes are deposited over the delta-doped monolayers on each side of the channel.