Molecular Beam Epitaxial Materials Study for Microwave and Millimeter Wave Devices.
Abstract
This report describes the study of molecular beam epitaxial materials for microwave and millimeter wave applications. Analytical techniques including electron diffraction, residual gas analyzer, Auger spectroscopy, electron microprobe, deep level trap spectroscopy, photoluminescence, Schottky barrier diodes, Hall measurements, and X-ray topography were used to relate the deposition conditions to the structural and electrical properties of unintentionally doped layers of GaAs grown by MBE. During the investigation, individual system components were identified which were incompatible with achieving low residual doping levels. Modifications in the system yielded epi-layers with reproducible background doping levels of the order of 10 to the 14th power to 10 to the 15th power/cu cm. Two n-type dopants (Sn and Ge) and one p-type dopant (Be) were investigated and used to grow layers for device evaluation. Millimeter wave mixer diodes fabricated from MBE GaAs showed high performance. Layers were also grown for Schottky barrier FETs, Schottky barrier and p(+)-n high-low IMPATTs, and p(+)-n hyperabrupt varactors, and the static characteristics of these devices were investigated. Barrier heights for Au, Al, and Ag Schottky diodes, on freshly grown layers were lower than barrier heights measured for diodes formed on oxidized GaAs layers. Epilayers of GaAs were also grown on (111) Ge substrates and surface characterizations made for evaluation of crystalline perfection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1978
- Accession Number
- ADA093049
Entities
People
- D. W. Covington
- E. J. Scheibner
- E. L. Meeks
- P. E. Mackie
- W. H. Hicklin
Organizations
- Georgia Tech