Organometallic Epitaxy for GaAs/AlGaAs Microwave Transistors and Integrated Circuits.
Abstract
Applications of atmospheric-pressure organometallic-grown GaAs-AlGaAs epitaxial (OMVPE) structures to potentially improved or new microwave FET structures were investigated. These included AlGaAs buffer layers for low-noise FETs, AlAs buffer layers for power FETs, and use of the selective etching of AlGaAs buffer layers to produce air-isolated FETs. The presence of increased trapping densities in the buffer layers, or surface states on the exposed channel layer in the case of the air-isolated structure, degraded rather than enhanced FET performance. Excellent performance was, however, obtained with conventional GaAs low-noise FETs grown entirely by OMVPE. HEMT structures were also grown by OMVPE, but did not show the increased mobilities of identical structures grown by MBE. GaAs/AlGaAs structures analogous to silicon MOSFETs were also fabricated. Inversion of p-type substrates (n-channel operation) could not be obtained but, unexpectedly, indications were obtained of successful inversion of n-type material (p-channel operation).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1983
- Accession Number
- ADA133569
Entities
People
- S. Bandy
- V. Aebi