Impact of crystallinity towards the performance of semi-polar (11-22) GaN UV photodetector
Document Type
Article
Publication Date
3-1-2021
Abstract
Crystal engineered semi-polar (11-22) GaN-based UV photodetectors have been fabricated which exhibit two dissimilar photo-responses depending on the crystal quality. The higher crystal quality evaluated via x-ray rocking curve (XRC) exhibited remarkable narrow full width half maximum (FWHM) along -1-123] and 1-100] of 0.11 degrees (396 arcsec) and 0.28 degrees (1008 arcsec), respectively. Integration of the high crystalline structure with the metal-semiconductor-metal type photodetector resulted in notably lower dark current of 4.6 mu A. The responsivity value is significantly enhanced from 117 mA/W to 325 mA/W with higher crystalline epilayer. The photo-response of the detector made with the enhanced crystal epilayer is measured to be as low as 170 ms with a recovery time of 241 ms by which is the fastest switching time ever reported in semi-polar (11-22) GaN metal-semiconductor-metal UV photodetector. (C) 2020 Elsevier B.V. All rights reserved.
Keywords
Epitaxial growth, Thin films, Semi-polar, GaN, UV photodetector
Divisions
Science
Funders
Fundamental Research Grant Scheme[FP078-2018A],RU Grant[ST025-2020],Collaborative Research in Engineering, Science and Technology Center[PV007-2019],Universiti Malaya Research Grant[RP039B-18AFR]
Publication Title
Materials Letters
Volume
286
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS