IEEE Photonics Journal (Jan 2018)
(In<italic><sub>x</sub></italic>Ga<sub>1−</sub><italic><sub>x</sub></italic>)<sub>2</sub>O<sub>3 </sub> Photodetectors Fabricated on Sapphire at Different Temperatures by PLD
Abstract
The (InxGa1_x)2O3 photodetectors were fabricated on the single-crystalline (InxGa1_x)2O3 films deposited on sapphire substrate by pulsed laser deposition. The structural and optical properties of the epilayers were investigated using high-resolution X-ray diffraction, X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and transmittance spectra. With decreasing the growth temperature, the indium composition increased and the bandgap decreased from 4.99 eV to 4.89 eV (In0.05Ga0.95)2O3 and 4.78 eV (In0.08Ga0.92)2O3. Furthermore, the photoelectrical characteristics of (InxGa1-x)2O3 detectors were also studied. The enhanced ' photo, ' dark, and responsivity R were achieved in the devices with higher In composition, while a larger number of defects were introduced, resulting in the significant persistent photoconductivity.
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