Sol-gel-derived gallium nitride thin films for ultraviolet photodetection

Abstract

Purpose

This study aims to explore the applicability of the sol-gel-derived GaN thin films for UV photodetection.

Design/methodology/approach

GaN-based ultraviolet (UV) photodetector with Pt Schottky contacts was fabricated and its applicability was investigated. The current-voltage (I-V) characteristics of the GaN-based UV photodetector under the dark current and photocurrent were measured.

Findings

The ideality factors of GaN-based UV photodetector under dark current and photocurrent were 6.93 and 5.62, respectively. While the Schottky barrier heights (SBH) for GaN-based UV photodetector under dark current and photocurrent were 0.35 eV and 0.34 eV, respectively. The contrast ratio and responsivity of this UV photodetector measured at 5 V were found to be 1.36 and 1.68 μA/W, respectively. The photoresponse as a function of time was measured by switching the UV light on and off continuously at different forward biases of 1, 3 and 6 V. The results showed that the fabricated UV photodetector has reasonable stability and repeatability.

Originality/value

This work demonstrated that GaN-based UV photodetector can be fabricated by using the GaN thin film grown by low-cost and simple sol-gel spin coating method.

Citation

Fong, C.Y., Ng, S.S., Mohd Amin, N., Yam, F.K. and Hassan, Z. (2019), "Sol-gel-derived gallium nitride thin films for ultraviolet photodetection", Microelectronics International, Vol. 36 No. 1, pp. 8-13. https://doi.org/10.1108/MI-12-2017-0074