We report AlGaN/GaN-based high-speed solar-blind photodetectors with indium-tin-oxide Schottky contacts. Current voltage, spectral responsivity, and high-frequency response characterizations were performed on the fabricated Schottky photodiodes. Low dark currents of < 1pA at 20 V reverse bias and breakdown voltages larger than 40 V were obtained. A maximum responsivity of 44 mA/W at 263 nm was measured, corresponding to an external quantum efficiency of 21%. True solar-blind detection was ensured with a cutoff wavelength of 274 nm. Time-based high-frequency measurements at 267 nm resulted in pulse responses with rise times and pulse-widths as short as 13 and 190 ps, respectively. The corresponding 3-dB bandwidth was calculated as 1.10 GHz.
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