Bandgap Engineered Ultraviolet Photodetectors with Gallium-Zinc-Oxide via Co-Sputtering Method. (1st January 2018)

• Record Type: Journal Article
• Authors: Yang, C. P.; Chang, S. P.; Chang, S. J.; Chen, S. X.; Hsu, M. H.; Tung, W. J.; Huang, W. L.; Chang, T. H.; Chiu, C. J.; Weng, W. Y.
• Is Part Of: ECS journal of solid state science and technology. Volume 7:Number 7(2018)
• Page Start: Q3083
• Page End: Q3088
• Publication Date: 2018-01-01
• Subjects: GZO -- MSM -- Ultraviolet photodetector; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2.0151807jss
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : The authors report the fabrication of gallium-zinc-oxide (GZO) MSM ultraviolet photodetectors (PDs) via co-sputtering using Ga2 O3 and ZnO targets. The cutoff wavelength of the fabricated PDs is changed by adjusting the radio frequency power of the ZnO target during the co-sputtering procedure. The GZO thin films are investigated via physical analysis, such as atomic force microscopy, absorption coefficient spectroscopy, and X-ray photoelectron spectroscopy. The results indicate that the smooth GZO thin films are composed of a wide-gap semiconductor and a clearly n-type material. With a 10-V applied bias, the corresponding IPhoto /IDark ratios for three devices labeled A, B, and C are 1.4 × 10 3, 9.3 × 10 2, and 2.7 × 10 3, respectively. Under corresponding cutoff wavelengths with a 0.2-V applied bias, the responsivity values are 2.7 × 10 −6, 9 × 10 −6, and 1.5 × 10 −4 for devices A, B, and C, respectively. Thus, these GZO ultraviolet PDs not only have a simple and low-cost fabrication process but also are suitable for ultraviolet sensing application owing to their outstanding electro-optical properties.