摘要： Epitaxial ?lms of b-(AlxGa1?x)2O3, b-Ga2O3, and b-(InxGa1?x)2O3 were grown on (001) sapphire substrates via metalorganic chemical vapor deposition (MOCVD). The compositions of the ?lms as determined from energy dispersive x-ray analysis (EDX) and x-ray photoelectron spectroscopy (XPS) results were XAl = 0.57 ± 0.05 and 0.76 ± 0.05 and XIn = 0.12 ± 0.05 and 0.21 ± 0.05. The optical bandgap was found to correspondingly vary between 6.0 ± 0.2 and 3.9 ± 0.1 eV, as a function of composition via XPS and UV–visible spectroscopy (UV–Vis). X-ray diffraction, scanning electron microscopy, and atomic force microscopy revealed the ?lms to be highly-oriented with nanocrystalline domains. Schottky- and MSM-based solar-blind UV photodetectors were fabricated on the ?lms and showed responsivities at 20 V varying from > 104 A/W for the Ga2O3 devices, > 103 A/W for the (AlxGa1?x)2O3 devices and > 102 A/W for the (InxGa1?x)2O3 devices. Modest shifts in wavelength selectivity corresponding with the changes in composition/bandgap were also measured. Time response measurements on Schottky and MSM detectors reveal rise and dwell times on the order of a minute, indicating the presence of photoconductive gain. Noise-equivalent powers were in the fW–pW regime with speci?c detectivities (D?) between 1010 and 1012 Jones. Scanning photocurrent maps display large photocurrent generation at the Schottky interface in the case of a b-Ga2O3 Schottky detector, whereas for an b-(InxGa1?x)2O3 MSM detector the photocurrent generation occurs in the device channel and at the Schottky interface.