A Solar-Blind Ultraviolet Photodetector With Graphene/MgZnO/GaN Vertical Structure

Graphene (Gr) has high transmittance to ultraviolet (UV) light and high mobility, which can effectively collect and transfer carriers. In this work, MgZnO (MZO) films were grown on the surface of the p-GaN by magnetron sputtering. A heterojunction solar-blind UV detector with Gr/MZO/GaN structure was constructed by introducing Gr as the window layer film. The test results show that the device has excellent detection ability for solar-blind UV light. The light response cut-off edge of the device is 263 nm, under the illumination of 255 nm and the bias voltage of −5 V, the responsivity is 14.6 mA/W, the rise time is 0.79 s, the decay time is 0.2 s, and the external quantum efficiency is 71.1%. The importance of this work lies in providing a reference for the application of Gr-based photodetectors.

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Design and Simulation of 4H-SiC MESFET Ultraviolet Photodetector with Gain

Materials Science Forum ◽

10.4028/www.scientific.net/msf.897.610 ◽

2017 ◽

Vol 897 ◽

pp. 610-613 ◽

Cited By ~ 1

Author(s):

Yun Bai ◽

Cheng Zhan Li ◽

Hua Jun Shen ◽

Cheng Yue Yang ◽

Yi Dan Tang ◽

...

Keyword(s):

Uv Light ◽

Gate Length ◽

Ultraviolet Photodetector ◽

Uv Detector ◽

Effect Mechanism ◽

Channel Layer ◽

Ultraviolet Detector ◽

Channel Thickness ◽

Simulation Results

The 4H-SiC ultraviolet detector of the MESFET structure with gain is proposed and simulated in this paper. The Schottky gate of MESFET is transparent or semi-transparent to allow more of the incident UV light to be absorbed in the device. The effect of the doping and thickness of the channel layer on the photocurrent of the 4H-SiC MESFET UV detector is simulated and the effect mechanism is analyzed. The simulation results show that the 4H-SiC MESFET exhibits photocurrent below 380 nm. And only when the channel of the 4H-SiC MESFET is in the open state there will be a gain in the detector. Shorter gate length is beneficial to improve the responsivity and the gain of the 4H-SiC MESFET UV detector. When the gate length is set to 10 μm with the channel thickness of 0.3 μm and channel doping of 1×1017 cm-3, the peak responsivity and the gain are calculated to be 12.9 A/W and 55.6 respectively.

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Effect of laser energy on the crystal structure and UV response characteristics of mixed-phase MgZnO thin films deposited by PLD and the fabrication of high signal/noise ratio solar-blind UV detector based on mix-phase MgZnO at lower voltage

Journal of Materials Chemistry C ◽

10.1039/c7tc02195j ◽

2017 ◽

Vol 5 (44) ◽

pp. 11472-11480 ◽

Cited By ~ 9

Author(s):

S. Han ◽

X. H. Ji ◽

Q. L. An ◽

Y. M. Lu ◽

P. J. Cao ◽

...

Keyword(s):

Thin Films ◽

Laser Energy ◽

Uv Light ◽

Mixed Phase ◽

High Signal ◽

Uv Detector ◽

Uv Detectors ◽

Response Characteristics ◽

Solar Blind ◽

Uv Response

UV detectors based on mixed-phase MgZnO thin films, synthesized at 24 J cm−2 and 26 J cm−2, could detect faint deep UV light under strong background noise.

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Enhancement of Responsivity in Solar-Blind UV Detector With Back-Gate MOS Structure Fabricated on β-Ga2O3 Films

Frontiers in Materials ◽

10.3389/fmats.2021.672128 ◽

2021 ◽

Vol 8 ◽

Author(s):

Dongdong D. Meng ◽

Xueqiang Q. Ji ◽

Dafang F. Wang ◽

Zhengwei W. Chen

Keyword(s):

Uv Light ◽

Fast Response ◽

Light Illumination ◽

Uv Detector ◽

Back Gate ◽

Uv Photodetectors ◽

Mos Structure ◽

Solar Blind ◽

Decay Times ◽

Excellent Stability

Monoclinic Ga2O3 (β-Ga2O3) films were grown on Si/SiO2 by using MOCVD. Then, we fabricated the solar-blind photodetector with a back-gate MOS structure. The device exhibited obvious photoresponse under 254-nm UV light illumination, and the photocurrent increased by five orders of magnitude, which could be controlled by VGS. The current generated under dark conditions could also be regulated by VGS and tended to constant when the regulation of VGS was reaching saturation. Meanwhile, VGS was confirmed to have a certain ability to regulate the photocurrent. The present device demonstrated excellent stability and fast response (rise) and recovery (decay) times under the 254-nm light illumination as well as a responsivity of 417.5 A/W, suggesting a valuable application in solar-blind UV photodetectors.

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Photocatalytic Discolouration of Solutions of Reactive Dyes in the Presence of H2O2

Water Quality Research Journal ◽

10.2166/wqrj.1995.009 ◽

1995 ◽

Vol 30 (1) ◽

pp. 53-60 ◽

Cited By ~ 1

Author(s):

Deng Nansheng ◽

Tian Shizhong ◽

Xia Mei

Keyword(s):

Photochemical Reaction ◽

Uv Light ◽

Reactive Dyes ◽

Solar Light ◽

Rate Equations ◽

Oh Radical ◽

Test Results ◽

Dye Molecules ◽

First Order ◽

Dye Solutions

Abstract Tests for the photocatalytic degradation of solutions of three reactive dyes, Red M-5B, Procion Blue MX-R and Procion Black H-N, in the presence of H2O2 were carried out. When the solutions of the three reactive dyes were irradiated by UV or solar light, the colour of the solutions disappeared gradually. A statistical analysis of the test results indicated a linear relation between the concentration of dyes and the time of irradiation. The discolouration reaction of the solutions was of the first order. Rate equations for the discolouration reactions of dye solutions were developed. The dark reactions or the dye solutions containing H2O2 were very slow, illustrating that the photochemical reaction played a very important role. It was demonstrated that UV light and solar light (300 to 380 nm) photolyzes the HO and that the resulting OH radical reacts with the dye molecules and destroys the chromophore.

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High-mobility induced high-performance self-powered ultraviolet photodetector based on single ZnO microwire/PEDOT:PSS heterojunction via slight Ga-doping

Journal of Material Science and Technology ◽

10.1016/j.jmst.2021.03.047 ◽

2021 ◽

Author(s):

Peng Wan ◽

Mingming Jiang ◽

Tong Xu ◽

Yang Liu ◽

Caixia Kan

Keyword(s):

High Performance ◽

High Mobility ◽

Ultraviolet Photodetector ◽

Self Powered ◽

Ga Doping

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Solution-assembled nanowires for high performance flexible and transparent solar-blind photodetectors

Journal of Materials Chemistry C ◽

10.1039/c4tc02297a ◽

2015 ◽

Vol 3 (3) ◽

pp. 596-600 ◽

Cited By ~ 32

Author(s):

Jiangxin Wang ◽

Chaoyi Yan ◽

Meng-Fang Lin ◽

Kazuhito Tsukagoshi ◽

Pooi See Lee

Keyword(s):

High Performance ◽

Switching Time ◽

Ultraviolet Photodetector ◽

Assembly Method ◽

Solar Blind

An all-NW ultraviolet photodetector with high photoresponse and improved switching time was fabricated by a solution assembly method.

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Solar-blind ultraviolet photodetector based on graphene/vertical Ga2O3 nanowire array heterojunction

Nanophotonics ◽

10.1515/nanoph-2018-0061 ◽

2018 ◽

Vol 7 (9) ◽

pp. 1557-1562 ◽

Cited By ~ 25

Author(s):

Tao He ◽

Yukun Zhao ◽

Xiaodong Zhang ◽

Wenkui Lin ◽

Kai Fu ◽

...

Keyword(s):

Response Times ◽

Nanowire Array ◽

Graphene Film ◽

Fast Response ◽

Nanowire Arrays ◽

Monolayer Graphene ◽

Ultraviolet Photodetector ◽

Solar Blind ◽

Decay Times ◽

First Time

AbstractIn this paper, a solar-blind ultraviolet photodetector (PD) based on the graphene/vertical Ga2O3 nanowire array heterojunction was proposed and demonstrated. To the best of our knowledge, it is the first time that vertical Ga2O3 nanowire arrays have been realized. Ga2O3 nanowires were obtained by thermally oxidizing GaN nanowires grown by molecular beam epitaxy on n-doped Si substrate. Then, a monolayer graphene film was transferred to Ga2O3 nanowires to form the graphene/vertical Ga2O3 nanowire array heterojunction and transparent electrodes. The fabricated device exhibited a responsivity (R) of 0.185 A/W and rejection ratio (R258 nm/R365 nm) of 3×104 at the bias of −5 V. Moreover, the fast response times of this PD were 9 and 8 ms for the rise and decay times under 254 nm illumination, respectively, which are attributed to the unique properties of nanowire arrays and the graphene/vertical Ga2O3 nanowire array heterojunction structure.

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