Metal–semiconductor–metal GaN ultraviolet photodetectors on Si(111)

TLDR: In this paper, the GaN epitaxial layers were grown on Si substrates by means of metalorganic chemical-vapor deposition and the response time of 4.8 ms was determined by measurements of photocurrent versus modulation frequency.

Abstract: GaN metal–semiconductor–metal photoconductive detectors have been fabricated on Si(111) substrates. The GaN epitaxial layers were grown on Si substrates by means of metalorganic chemical-vapor deposition. These detectors exhibited a sharp cutoff at the wavelength of 363 nm and a high responsivity at a wavelength from 360 to 250 nm. A maximum responsivity of 6.9 A/W was achieved at 357 nm with a 5 V bias. The relationship between the responsivity and the bias voltage was measured. The responsivity saturated when the bias voltage reached 5 V. The response time of 4.8 ms was determined by the measurements of photocurrent versus modulation frequency.