Solar-Blind Avalanche Photodetector Based On Single ZnO–Ga₂O₃ Core–Shell Microwire

Abstract

High-performance solar-blind (200-280 nm) avalanche photodetectors (APDs) were fabricated based on highly crystallized ZnO-Ga2O3 core-shell microwires. The responsivity can reach up to 1.3 × 10(3) A/W under -6 V bias. Moreover, the corresponding detectivity was as high as 9.91 × 10(14) cm·Hz(1/2)/W. The device also showed a fast response, with a rise time shorter than 20 μs and a decay time of 42 μs. The quality of the detectors in solar-blind waveband is comparable to or even higher than that of commercial Si APD (APD120A2 from Thorlabs Inc.), with a responsivity ∼8 A/W, detectivity ∼10(12) cm·Hz(1/2)/W, and response time ∼20 ns. The high performance of this APD make it highly suitable for practical applications as solar-blind photodetectors, and this core-shell microstructure heterojunction design method would provide a new approach for realizing an APD device.

Novel BeZnO Based Self‐Powered Dual‐Color UV Photodetector Realized via a One‐Step Fabrication Method

“…To further investigate the signal‐to‐noise ratio of the self‐powered device, linear dynamic range (LDR, unit with dB) is calculated to evaluate the performance of this photodetector. Generally, LDR can be calculated from the following equation: where is the photocurrent under 330 nm with a power density of 1.68 mW/cm 2 , is the dark current. The calculated LDR of the BeZnO self‐powered photodetector is 60 dB.…”

“…The spectral responsivity is a critical parameter which is used to evaluate the performance of a photodetector. This parameter is defined as the photocurrent flowing in the detector divided by incident optical power and is expressed by the following equation: where is the photocurrent, is the dark current, λ is irradiation wavelength, P is the light power density and S is the effective irradiated area, respectively. As shown in Figure (a), two response cut‐off wavelengths are obviously observed in the spectral response spectra under 0 V. In addition, two cut‐off wavelengths are found to be at ∼275 nm and ∼360 nm, which are located at UVC and UVA region, respectively.…”

An Overview of the Ultrawide Bandgap Ga2O3 Semiconductor-Based Schottky Barrier Diode for Power Electronics Application

“…However, its wide bandgap can compensate for this disadvantage since thinner drift layer has smaller depletion width; thus, the parasitic capacitance can be decreased to meet the requirements of high-frequency applications. Besides, the bandgap of about 4.8 eV makes Ga 2 O 3 possess special absorption wave band (250–280 nm) which is just located in the range of solar blind ultraviolet (UV) ray, so Ga 2 O 3 is a natural good material for fabricating UV detectors [44–47].

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Diameter Tuning of β $$ \beta $$ -Ga2O3 Nanowires Using Chemical Vapor Deposition Technique

“…Recently, beta gallium oxide (β-Ga 2 O 3 ) with its one dimensional morphology is emerging as one of the potential semiconductor oxide nanomaterial. It has shown promising device applications including high-temperature gas sensors, UV photodetectors, high power field effect transistors (FET), and photonic switches [2, 3, 9–15]. β-Ga 2 O 3 exhibits advantageous properties including large band-gap with E g  ~ 4.7–4.9 eV at room temperature (RT), high breakdown field of 8 MVcm −1 , and outstanding thermal and chemical stability at high temperatures [11, 16–19].…”