Self-catalyst β-Ga₂O₃ semiconductor lateral nanowire networks synthesis on the insulating substrate for deep ultraviolet photodetectors

Abstract

Monoclinic gallium oxide (β-Ga2O3) is a super-wide bandgap semiconductor with excellent chemical and thermal stability, which is an ideal candidate for detecting deep ultraviolet (DUV) radiation (wavelength from 200 nm to 280 nm).

InGaO3 Nanowire Networks for Deep Ultraviolet Photodetectors

“…In the appropriate growth time, the precursor supply is stable, and the barometric stability is high, so secondary nucleation can be avoided, which is why the growth time of NWs should not be too long. , Moreover, the SEM images of the InGaO 3 NW networks grown under different pressures at 700 °C are shown in Figure S2. Normally, NWs grow under relatively high pressures, , but the synthesis of the NW network reported here can also be achieved and maintained stable at high vacuum levels. Below 500 Pa, the quality of NWs obtained is higher, and the high vacuum environment is conducive to the growth of nanoparticles.…”

“…In order to further clarify the optical response characteristics of the photodetector, the photoelectric conversion capability can be well described by calculating the optical responsiveness ,, R λ = I normalp normalh − I normald P S where I ph is the photocurrent, I d is the dark current, P is the incident optical power density, and S is the effective illumination area of device. In this experiment, the power density of the incident UV light is 16.56 μW/cm 2 , and the effective illumination area is 0.16 cm 2 .…”

“…In this experiment, the power density of the incident UV light is 16.56 μW/cm 2 , and the effective illumination area is 0.16 cm 2 . In addition, the external quantum efficiency (EQE) and the detectability are two important parameters to appraise the performance of a photodetector, which is given by the following definition ,, normalE normalQ normalE = h c R e λ D * = R S 1 / 2 false( 2 e I normald false) 1 / 2 where R is the responsivity, h is Planck’s constant, λ is the illumination wavelength (254 nm), e is the electronic charge (1.6 × 10 –19 C), c is the velocity of light, and S is the effective area of the detector. As given in Figure f, under 1 V bias, the corresponding photocurrent gradually decreases from 1.7 to 6.5 μA with the increase of light intensity.…”

Observation of Anomalous Negative Photoconductivity in Ga2O3 Nanowires: Implications for Broadening the Spectral Response of Photodetectors

“…7,9−13 Among them, Ga 2 O 3 has five phases (α, β, γ, δ, and ε). Nanostructured β-Ga 2 O 3 has the property of chemical and thermal stability, 1,14,15 with a direct bandgap (4.5−4.9 eV), 3,16,17 and the corresponding absorption edge just falls within the solar-blind range (200−280 nm), so it has been widely explored in recent years as a promising candidate for a solar-blind photodetector.…”

“…Solar radiation with the spectral range from 200 to 280 nm cannot reach the earth’s surface because it is absorbed by ozone in the atmosphere, so it is called solar-blind light. − A wide bandgap semiconductor can be used as the material for solar-blind photodetectors because its absorption edge is falling within the range of solar-blind region, which is widely applied for ozone hole monitoring, fire detection, safety communication, and missile guidance system. ,− ZnO, Al x Ga 1– x N, BN, Zn x Mg 1– x O, Ga 2 O 3 , and diamond are the representatives of wide bandgap semiconductor materials, which have attracted tremendous attention in recent years. ,− Among them, Ga 2 O 3 has five phases (α, β, γ, δ, and ε). Nanostructured β-Ga 2 O 3 has the property of chemical and thermal stability, ,, with a direct bandgap (4.5–4.9 eV), ,, and the corresponding absorption edge just falls within the solar-blind range (200–280 nm), so it has been widely explored in recent years as a promising candidate for a solar-blind photodetector.…”