Material and device properties of GaAs on sapphire grown by metalorganic chemical vapor deposition

摘要

Surface morphology, electron mobility, and photoluminescence (PL) spectrum have been investigated for the epitaxial layers of GaAs on (0001) sapphire grown at several temperatures. The optimum growth temperature range is determined to be around 690 °C. The mobility and the PL intensity efficiency are improved by increasing the layer thickness, due to the decrease of defect density. The structure related to the defects is located at a wavelength of 1.04 μm in the PL spectra. We fabricate the first field‐effect transistor on GaAs on sapphire, and it has a transconductance of 20 mS/mm for a gate length of 2.5 μm.