GaAs/GaN Strained Layer Superlattice Materials for High Temperature Transistors.Phase 1

摘要

During this program, we were successful in depositing Single crystal layers ofGaAs on GaAs on GaN epilayers and single crystal GaN on GaAs substrates. These two developments represent an important advance in the technology base required to grow GaN/GaAs short period superlattices. Due to the large difference in bandgap energy between GaAs and GaN (1.4-3.6 eV), superlattices based on these two materials can potentially provide electronic devices which operate at elevated temperatures over a wide range of wavelengths (365-860 nm). For the first time, tertiary butyl arsine (TBA) was used to grow GaAs on GaN substrates. From an industry safety perspective, this is extremely important since TBA is less toxic and deadly as compared to pure arsine. During this program, the growth of ternary GaAsN was also attempted. Unfortunately, poor results were obtained and further growths were curtailed. During the growth of the ternary GaAsN, an important growth aspect was determined. When attempting to grow GaAsN at low temperatures, arsenic incorporation far exceeded nitrogen leaving the film GaAs. At elevated temperatures, nitrogen was preferentially incorporated leaving a GaN film. Such growth knowledge will prove important for future GaAs/GaN Superlattice work. During this program, we were successful in depositing Single crystal GaN-GaAs, GaN/GaAs Superlattices.