The Structural and Photoelectrical Properties of Gallium Oxide Thin Film Grown by Radio Frequency Magnetron Sputtering

Abstract

Gallium oxide thin films were deposited by radio frequency magnetron sputtering technique. Structural, optical and photoelectrical properties of Ga 2 O 3 thin films were investigated in detail. The as-grown Ga 2 O 3 thin films were amorphous, while those annealed film were polycrystalline with monoclinic structure. Amorphous and polycrystalline gallium oxide metal-semiconductor-metal photodetectors were fabricated. However, annealed polycrystalline films have no photoresponse for deep ultraviolet light. The responsivity of the photodetector based on as-grown amorphous film is 122.7 μA/W at 256 nm and the ultraviolet (UV)-to-visible rejection ratios were 100, which indicates that the amorphous Ga 2 O 3 thin films have potential application for solar-blind photodetector. High concentration of oxygen vacancies of amorphous film are considered to be responsible for photoresponse in amorphous gallium oxide thin films.

Recent Progress of Deep Ultraviolet Photodetectors using Amorphous Gallium Oxide Thin Films

“…In 2019, Jiao et al deposited a‐Ga 2 O 3 thin films at RT and annealed these films at 500, 600, 700, 800, and 900 °C in air ambiance. [ 17 ] MSM PDs with Au electrodes were constructed with these as‐grown and annealed thin films, respectively. Compared with the apparently more than two orders of magnitude UV response of the as‐grown a‐Ga 2 O 3 thin film, the polycrystalline β‐Ga 2 O 3 films after annealed at high temperatures show photocurrents under 254 nm light in the same level as the dark current ( Figure ), indicating that a‐Ga 2 O 3 thin film has potential applications for solar‐blind UV photodetection.…”

“…Reproduced under the terms of the Creative Commons Attribution 4.0 license. [ 17 ] Copyright 2019, The Authors, published by Electrochemical Society.…”

“…This phenomenon was attributed to the reduction of oxygen vacancies caused by the increase in oxygen content during deposition, revealing the importance of the oxygen processing gas in promoting photodetector performance. [17] Copyright 2019, The Authors, published by Electrochemical Society. Reproduced with permission.…”

“…[14][15][16] It is quite interesting that the performance of UV PD using a-GaO x is comparable or even better than its crystalline counterpart. [15,17] Except for UV PDs, a-GaO x materials also have extensive applications in areas of solar cells, [18][19][20][21] phosphors, [22,23] resistance random access memories (RRAMs), [24][25][26][27] gas sensors, [28] and radiation detectors. [29] These versatile applications together with the fact that scalable a-GaO x can be easily prepared on almost any substrates make it appealing for flexible electronics and giant microelectronics.…”

Epitaxial Growth and Solar‐Blind Photoelectric Characteristic of Ga2O3 Film on Various Oriented Sapphire Substrates by Plasma‐Enhanced Chemical Vapor Deposition

“…At present, the Ga 2 O 3 epitaxial films have been grown on sapphire (Al 2 O 3 ) substrates by various epitaxial growth techniques, including halide vapor phase epitaxy (HVPE), [ 7,8 ] metal organic chemical vapor deposition (MOCVD), [ 9,10 ] and low pressure chemical vapor deposition (LPCVD). [ 11,12 ] The epitaxial films grown by traditional physical methods (pulsed laser deposition [PLD], [ 13 ] molecular beam epitaxy [MBE], [ 14 ] and sputter [ 15 ] ) exhibit the high crystal quality, while the growth rate is low which limits the application in the industrial production. Although the Ga 2 O 3 epitaxial films via HVPE have a fast growth rate, the surface morphology is rough which is unsuitable for the device.…”