Investigation of Technological Problems in GaAs
Semi-annual technical rept. no. 3, 16 Jan-15 Jul 1976
ROCKWELL INTERNATIONAL CORP THOUSAND OAKS CA SCIENCE CENTER
Pagination or Media Count:
Significant progress in areas of GaAs technology with impact on the development of microwave FET devices is reported. Improvement in the yield of bulk semi-insulating GaAs substrate material has been achieved by refining fabrication procedures. Transport measurements on semi-insulating GaAs have led to interpretation of the electrical compensation in terms of a deep-donor-deep- acceptor model. Transient capacitance measurements have confirmed that the growth of FET active layers on high-resistivity buffer layers results in the elimination of interface traps. In ion implantation, a simple annealing technique which avoids the use of any protective cap has been successfully applied to high dose Se implants. A test to preselect substrates for ion implantation has been developed, leading to good reproducibility of carrier concentration profiles. Accurate measurements of ionization coefficients have confirmed the dependence of electron ionization rates on doping density. Improved RF performance has been achieved from FET devices made on Se implanted layers. These devices are free from short term drift problems exhibited by transistors made on epitaxial layers.
- Electrical and Electronic Equipment
- Solid State Physics