Hemt structure with passivated donor layer

US5172197A · kind A · utility

Assignee

• Hughes Aircraft Company · US

Inventors

• Loi D. Nguyen · Thousand Oaks, US
• Michael J. Delaney · Thousand Oaks, US
• Lawrence E. Larson · Del Mar, US
• Umesh Mishra · Montecito, US

Key dates

• Filing date: Dec 20, 1991
• Grant date: Dec 15, 1992
• Expiry date: Dec 20, 2011

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A channel layer, donor layer, Schottky layer, and cap layer are formed on a substrate. A source and drain are formed on the cap layer. A gate is formed on the cap layer, or at the bottom of a recess which is formed through the cap layer and partially extends into the Schottky layer. The donor and Schottky layers are formed of a semiconductive material which includes an oxidizable component such as aluminum. A passivation or stop layer of a lattice-matched, non-oxidizable material is formed underlying the source, drain, and gate, and sealingly overlying the donor layer. The stop layer may be formed between the Schottky layer and the donor layer, or constitute a superlattice in combination with the Schottky layer consisting of alternating stop and Schottky sublayers. Alternatively, the stop layer may sealingly overlie the Schottky layer, and further constitute the cap layer.