title: High-performance GaN metal-insulator-semiconductor ultraviolet photodetectors using gallium oxide as gate layer.
abstract: In this study, gallium nitride (GaN)-based metal-insulator-semiconductor (MIS) ultraviolet (UV) photodetectors (PDs) with a gallium oxide (GaO(x)) gate layer formed by alternating current bias-assisted photoelectrochemical oxidation of n-GaN are presented. By introducing the GaO(x) gate layer to the GaN MIS UV PDs, the leakage current is reduced and a much larger UV-to-visible rejection ratio (R(UV/vis)) of spectral responsivity is achieved. In addition, a bias-dependent spectral response results in marked increase of the R(UV/vis) with bias voltage up to ~10(5). The bias-dependent responsivity suggests the possible existence of internal gain in of the GaN MIS PDs.
authors.affiliation: Department of Electro-Optical Engineering, Southern Taiwan University, Tainan County 71001, Taiwan. minglun@mail.stut.edu.tw
authors.forename: Ming-Lun
authors.initials: ML
authors.lastname: Lee
authors.forename: T S
authors.initials: TS
authors.lastname: Mue
authors.forename: F W
authors.initials: FW
authors.lastname: Huang
authors.forename: J H
authors.initials: JH
authors.lastname: Yang
authors.forename: J K
authors.initials: JK
authors.lastname: Sheu
mesh_terms: D004581:Electronics; D005708:Gallium / Q000737:chemistry*; D055096:Optical Devices; D055095:Optics and Photonics / Q000295:instrumentation / Q000379:methods*; D055668:Photochemical Processes; D012666:Semiconductors; D014466:Ultraviolet Rays
chemical_list: C473348:gallium nitride; C038863:gallium oxide; D005708:Gallium