High-performance solar-blind ultraviolet photodetector based on mixed-phase ZnMgO thin film

Journal Article · Mon Jul 07 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4889914· OSTI ID:22303932

Fan, M. M. ^[1]; Zhang, Z. Z.; Li, B. H.; Chen, X.; Zhao, D. X.; Shan, C. X.

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1. Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China)

High Mg content mixed-phase Zn{sub 0.38}Mg{sub 0.62}O was deposited on a-face sapphire by plasma-assisted molecular beam epitaxy, based on which a metal-semiconductor-metal solar-blind ultraviolet (UV) photodetector was fabricated. The dark current is only 0.25 pA at 5 V, which is much lower than that of the reported mixed-phase ZnMgO photodetectors. More interestingly, different from the other mixed-phase ZnMgO photodetectors containing two photoresponse bands, this device shows only one response peak and its −3 dB cut-off wavelength is around 275 nm. At 10 V, the peak responsivity is as high as 1.664 A/W at 260 nm, corresponding to an internal gain of ∼8. The internal gain is mainly ascribed to the interface states at the grain boundaries acting as trapping centers of photogenerated holes. In view of the advantages of mixed-phase ZnMgO photodetectors over single-phase ZnMgO photodetectors, including easy fabrication, high responsivity, and low dark current, our findings are anticipated to pave a new way for the development of ZnMgO solar-blind UV photodetectors.

• OSTI ID: 22303932
• Journal Information: Applied Physics Letters, Vol. 105, Issue 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CURRENTS
FABRICATION
GAIN
GRAIN BOUNDARIES
HOLES
INTERFACES
MAGNESIUM COMPOUNDS
METALS
MOLECULAR BEAM EPITAXY
OXYGEN COMPOUNDS
PHOTODETECTORS
PLASMA
SAPPHIRE
SEMICONDUCTOR MATERIALS
SOLAR RADIATION
THIN FILMS
TRAPPING
ULTRAVIOLET RADIATION
ZINC COMPOUNDS