High bandwidth-efficiency solar-blind AlGaN Schottky photodiodes with low dark current

Abstract

Cataloged from PDF version of article.Al0.38Ga0.62N/GaN heterojunction solar-blind Schottky photodetectors with low dark current, high responsivity, and fast pulse\ud response were demonstrated. A five-step microwave compatible fabrication process was utilized to fabricate the devices. The solarblind\ud detectors displayed extremely low dark current values: 30lm diameter devices exhibited leakage current below 3 fA under\ud reverse bias up to 12V. True solar-blind operation was ensured with a sharp cut-off around 266 nm. Peak responsivity of\ud 147mA/W was measured at 256 nm under 20 V reverse bias. A visible rejection more than 4 orders of magnitude was achieved.\ud The thermally-limited detectivity of the devices was calculated as 1.8 · 1013 cmHz1/2W 1\ud . Temporal pulse response measurements\ud of the solar-blind detectors resulted in fast pulses with high 3-dB bandwidths. The best devices had 53 ps pulse-width and 4.1GHz\ud bandwidth. A bandwidth-efficiency product of 2.9GHz was achieved with the AlGaN Schottky photodiodes. (C) 2004 Elsevier Ltd. All rights reserve

On the profile of frequency dependent dielectric properties of (Ni/Au)/GaN/Al0.3Ga0.7N heterostructures

“…Therefore, GaN and some other compounds have been studied extensively for their applications in short wavelength optical and high-power/temperature devices, such as light emitting diodes (LEDs), laser diodes (LDs), metal-semiconductor (MS) Schottky barrier diodes (SBDs), metal-insulator-semiconductor high-electron-mobility transistors (MISHEMTs). GaN high-electron-mobility transistors (HEMTs) with Schottky/rectifier metal contact have demonstrated excellent highfrequency, high-power, high temperature and recently good microwave-noise characteristics [1][2][3][4][5][6][7][8][9][10]. The performance level of GaN/ AlGaN HEMT devices has increased rapidly over the last few years.…”

High responsivity in molecular beam epitaxy grown β-Ga2O3 metal semiconductor metal solar blind deep-UV photodetector

“…6 Fig . 5 illustrates the plot of the responsivity versus dark current for the state-of-the-art solar blind (230-290 nm) UV detectors reported [4][5][6]8,[10][11]16,[30][31][32][33][34][35][36][37] for the devices based on Al x Ga 1-x N as well as on β-Ga 2 O 3 . The detectors reported in this work have excellent responsivity while maintaining a very low dark current for 230-240 nm range.…”

Dynamics of AlGaN based detectors in the deep-UV

“…6. Tut et al [13], have recently observed a similar trend in high-bandwidth efficient solar blind AlGaN Schottky photodiodes. The first exponential has been associated to the RC time constant and the other one is due to carrier trapping effects.…”