Article
Engineering, Electrical & Electronic
Vera M. Kalygina, Alexander V. Tsymbalov, Aleksei Almaev, Bogdan O. Kushnarev, Vladimir L. Oleinik, Julianna V. Petrova, Pavel A. Yunin
Summary: In this study, the effect of radiation below the beta-Ga2O3 band-gap on the photoelectric characteristics of gallium oxide thin films based UV radiation detectors is investigated. The gallium oxide film is deposited using radio frequency magnetron sputtering, and interdigital electrodes are formed with an inter-electrode distance of 30 μm. The detectors show high photocurrent values under irradiation with a wavelength of 254 nm and intensity of 780 μW/cm^2. Persistent photoconductivity and increased stability of the detectors are attributed to the high concentration of traps in the Ga2O3 film and their recharging under UV irradiation.
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Yanan Zhang, Shujie Jiao, Junhua Zhang, Shuo Liu, Dongbo Wang, Shiyong Gao, Jinzhong Wang
Summary: A GaOOH/Ga2O3 heterojunction was achieved through a one-step annealing treatment, and its solar blind photoresponse performance was characterized using photoelectrochemical detectors. The results showed that the GaOOH/Ga2O3 heterojunction detector exhibited superior performance in pure solar-blind ultraviolet detection.
Article
Engineering, Electrical & Electronic
Wei Mi, Jinze Tang, Xinrong Chen, Xinwei Li, Bingkun Li, Liyuan Luo, Liwei Zhou, Rongrong Chen, Di Wang, Jinshi Zhao
Summary: PIN-structured photodiodes were fabricated by sputtering intrinsic-Ga2O3 and n-Ga2O3 with Ti doping on p-Si substrates. The fabricated Ga2O3 films were amorphous, and the roughness increased with Ti doping concentration. The photodiodes showed high reverse breakdown voltages, significant photoelectric response to 254 nm UV light, and high responsivity at -10 V bias.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Multidisciplinary
Jie Zhang, Fengjing Liu, Dong Liu, Yanxue Yin, Mingxu Wang, Zixu Sa, Li Sun, Xiaoxin Zheng, Xinming Zhuang, Zengtao Lv, Wenxiang Mu, Zhitai Jia, Yang Tan, Feng Chen, Zai-xing Yang
Summary: The study investigates the photodetection performance of thin amorphous Ga2O3 nanosheet, which has been widely used as dielectric and passivation materials. By peeling off from the Ga solid-melt surface, the amorphous Ga2O3 nanosheet is confirmed to have an amorphous characteristic through selected area electron diffraction and X-ray diffraction. However, due to limited absorption ability and abundant defect states, the amorphous Ga2O3 nanosheet shows low photocurrent and slow response time even at a bias voltage. To enhance the photodetection performance, PbI2 nanosheet is grown on the surface of the amorphous Ga2O3 nanosheet, forming a Ga2O3/PbI2 heterojunction photodetector. The heterojunction photodetector exhibits larger photocurrent (1.6 nA) and faster response times (2 ms rise time and 3 ms decay time) even at a zero bias voltage, and it also shows excellent self-powered photoresponse characteristic and mechanical flexibility when configured into a flexible photodetector. This work provides a pathway for the development of high-performance flexible optoelectronic devices.
MATERIALS TODAY PHYSICS
(2023)
Article
Materials Science, Ceramics
Chen Wang, Wei-Hang Fan, Yu-Chao Zhang, Pin-Chun Kang, Wan-Yu Wu, Dong-Sing Wuu, Shui-Yang Lien, Wen-Zhang Zhu
Summary: This study investigated the properties of Sn-doped Ga2O3 films deposited on sapphire substrates through RF magnetron sputtering at different oxygen flow ratios. In situ optical emission spectroscopy was used to monitor the plasma radicals generated during the deposition process. The films showed amorphous structures with nanoparticles and a decreased deposition rate with increasing oxygen flow ratio. The conductive mechanism of the films was attributed to the ratio of substitutional Sn atoms and the SnO2 phase. Metal-semiconductor-metal solar-blind photodetectors were developed and analyzed to demonstrate the effect of oxygen flow ratio.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Namsoo Lim, Jungwook Min, Jung-Hong Min, Chun Hong Kang, Kuang-Hui Li, Tae -Yong Park, Woochul Kim, Bambar Davaasuren, Tien Khee Ng, Boon S. Ooi, Deok Ha Woo, Ji-Hyeon Park, Yusin Pak
Summary: Orthorhombic kappa-Ga2O3 is a promising ultrawide bandgap material for extreme environment devices. In this study, a kappa-Ga2O3 film was fabricated using metal organic chemical vapor deposition, and its crystallinity was analyzed by X-ray diffraction and transmission electron microscopy. The results demonstrate that this material has excellent ultraviolet-C detection capabilities.
APPLIED SURFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Naveen Kumar, Malkeshkumar Patel, Joondong Kim, Chaehwan Jeong, Ching-Ping Wong
Summary: UV radiation can have chronic effects on human skin and eyes, but blocking it and utilizing its energy can lead to breakthroughs in medical field and energy production. In this study, a lightweight, flexible Ga2O3/Cu2O heterojunction was developed for photovoltaics and photodetectors, which showed UV blocking capability, high durability, and flexibility.
APPLIED MATERIALS TODAY
(2022)
Article
Engineering, Electrical & Electronic
Jianming Lei, Qing Cai, Jiying Cao, Tongchuan Ma, Jiandong Ye, Dunjun Chen
Summary: A high-performance epsilon-Ga2O3 solar-blind photodetector was successfully fabricated using an interdigital structure. The device exhibited a prominent response peak at 240 nm and a cutoff edge at 266 nm, with a solar-blind UV in-band/out-of-band rejection ratio of 10^5 and a photo-to-dark-current ratio exceeding 10^5. The impact of varying interdigital spacing on device performance was investigated, showing that decreasing spacing increased light current and responsivity, while increasing spacing reduced dark current.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Materials Science, Coatings & Films
Ayeong Kim, Geonyeop Lee, Jihyun Kim
Summary: This study demonstrates energy-efficient capacitive sensing of deep-UV wavelengths by integrating UWBG β-Ga2O3 semiconductor with graphene electrode, eliminating the need for a solar-blind deep-UV bandpass filter. The high optical transmittance of graphene enables UV-C light absorption in β-Ga2O3, facilitating carrier transport. The photodetector shows excellent sensing performance with reproducibility and spectral selectivity at various frequencies and bias conditions.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Chemistry, Physical
Shan Li, Yusong Zhi, Chao Lu, Chao Wu, Zuyong Yan, Zeng Liu, Jian Yang, Xulong Chu, Daoyou Guo, Peigang Li, Zhenping Wu, Weihua Tang
Summary: The paper presents a broadband ultraviolet self-powered photodetector based on a beta-Ga2O3/CuI heterostructure, demonstrating excellent performance under UVC light and remarkable stability. Insights into the intrinsic physical behaviors of the device are investigated through energy band diagrams and first principle calculations.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Sa Cai, Chaolei Zuo, Jiayu Zhang, Hui Liu, Xiaosheng Fang
Summary: A paper-based wearable photodetector is reported, which can simultaneously measure transient light intensity and accumulated light dosage. The photodetector fully utilizes the natural hygroscopicity and softness of paper, showing decent flexibility. This work introduces a new type of wearable photodetector by structure design and material selection, shedding light on more novel works for convenient and practical photodetection.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Lingxing Xiong, Lei Zhang, Qipu Lv, Tao Li, Wenqing Song, Jiawei Si, Wenhui Zhu, Liancheng Wang
Summary: A bendable and thermally stable solar-blind UV photodetector based on Ni/a-Ga2O3/a-AlN/Cu foil structure has been demonstrated, showing stable UV response characteristics with different bending radii and temperatures, high responsivity, and fast response time, suitable for harsh environments such as high-power bendable electron devices, flame detection, etc.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Xiao-Xi Li, Guang Zeng, Yu-Chun Li, Hao Zhang, Zhi-Gang Ji, Ying-Guo Yang, Man Luo, Wei-Da Hu, David Wei Zhang, Hong-Liang Lu
Summary: This article presents a high responsivity and fully flexible Ta-doped beta-Ga2O3 DUV phototransistor with outstanding optoelectrical properties and mechanical flexibility, showing potential applications in UV imaging and artificial intelligence.
NPJ FLEXIBLE ELECTRONICS
(2022)
Article
Optics
Zhihua Zheng, Wen Wang, Feng Wu, Zhiyuan Wang, Maocheng Shan, Yongming Zhao, Weijie Liu, Pengcheng Jian, Jiangnan Dai, Hai Lu, Changqing Chen
Summary: Motivated by the goals of fabricating a highly reliable, high performance, and cost-efficient self-powered photodetector, researchers have developed an organic-inorganic hybrid solar-blind ultraviolet photodetector. The device exhibits high responsivity, sharp cut-off edge, and excellent detection capabilities, making it suitable for solar-blind UV detection.
Article
Materials Science, Multidisciplinary
Song Qi, Jiahang Liu, Jianying Yue, Xueqiang Ji, Jiaying Shen, Yongtao Yang, Jinjin Wang, Shan Li, Zhenping Wu, Weihua Tang
Summary: In this work, a graphene/beta-Ga2O3/Ag asymmetric Schottky junction photodetector was constructed to address the issue of elevated dark currents in existing graphene/Ga2O3 devices. By taking advantage of the asymmetric structure design to suppress dark current and the transparent graphene electrode to increase carrier collection efficiency, the device achieved outstanding responsivity, detectivity, external quantum efficiency, and response time. Importantly, it exhibited low dark current and high light-to-dark ratio. Overall, the graphene/beta-Ga2O3/Ag asymmetric Schottky junction photodetector has considerable potential as a deep ultraviolet detector.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
Zeng Liu, Ling Du, Shao-Hui Zhang, Ang Bian, Jun-Peng Fang, Chen-Yang Xing, Shan Li, Jin-Cheng Tang, Yu-Feng Guo, Wei-Hua Tang
Summary: A flower-like SnO2-SnO/porous GaN (FSS/PGaN) heterojunction was fabricated for the first time, involving a spraying process, hydrothermal preparation of FSS, and electrochemical wet etching of GaN. The loaded SnO2-SnO composites with p-n junctions on the PGaN surface exhibited excellent transport capability, achieving a short response time and release time for H2S sensing. The obtained sensor showed high stability and potential for various applications.
Article
Physics, Multidisciplinary
Li-Li Yang, Yu-Si Peng, Zeng Liu, Mao-Lin Zhang, Yu-Feng Guo, Yong Yang, Wei-Hua Tang
Summary: A self-powered solar-blind ultraviolet (UV) photodetector (PD) was successfully fabricated on a Ga2O3/Bi2WO6 heterojunction. The PD demonstrated a distinct photovoltaic effect and excellent photodetection performance with an ultra-low dark current and a high light-to-dark current ratio in self-powered mode. The PD also showed a stable and fast response speed under different light intensities and voltages. Overall, the Ga2O3/Bi2WO6 heterojunction has the potential to be a candidate for self-powered and high-performance UV photodetectors.
Article
Physics, Multidisciplinary
Jian-Ying Yue, Xue-Qiang Ji, Shan Li, Xiao-Hui Qi, Pei-Gang Li, Zhen-Ping Wu, Wei-Hua Tang
Summary: In this study, solar-blind ultraviolet photodetectors with metal-semiconductor-metal structure were fabricated using β-(Al0.25Ga0.75)x(2)O(3)/β-Ga2O3 film. The performance of the β-Ga2O3 detector was significantly improved after surface passivation with β-(Al0.25Ga0.75)(2)O-3.
Article
Engineering, Electrical & Electronic
Xiao-Hui Qi, Zeng Liu, Xue-Qiang Ji, Jian-Ying Yue, Yu-Song Zhi, Shan Li, Zu-Yong Yan, Yu-Feng Guo, Wei-Hua Tang
Summary: In this article, a deep-ultraviolet (DUV) photodetector (PD) based on a Ga2O3/TiO2 planar heterojunction is fabricated using both the solution and the metalorganic chemical vapor deposition (MOCVD) methods. The PD exhibits impressive DUV sensing properties, including high responsivity (R), specific detectivity (D-*), and external quantum efficiency (EQE). The PD can operate stably in a self-powered mode and has potential for applications in energy-conserving DUV sensing systems.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Jiawei Zhang, Yixuan Cui, Chunxiao Liu, Xiangfu Wang, Weihua Tang
Summary: This paper introduces a new flexible pressure sensor designed with LIG/AgNWs composite to improve ultra-high sensitivity and stability. The dependence of sensor property on LIG/NMP concentration and coating layers was studied, and the sensor showed good sensitivity (56.9 kPa(-1)) and stable performance. Its application in bending fingers and high fives was also studied, and results demonstrate its suitability for human body dynamic posture monitoring.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Jinjin Wang, Xueqiang Ji, Zuyong Yan, Xu Yan, Chao Lu, Zhitong Li, Song Qi, Shan Li, Xiaohui Qi, Sai Zhang, Shengrun Hu, Peigang Li
Summary: Ga2O3 thin films were successfully prepared by one-step thermal oxidation of p-GaN thin films. The photodetector showed significantly reduced dark current and maintained the same order of magnitude of photocurrent, resulting in a large photo-to-dark current ratio. The device also exhibited high responsivity, super high external quantum efficiency, large detectivity, and fast response speed. The results demonstrate that the one-step thermal oxidation method is effective for preparing devices with high sensitivity, fast response, and high-resolution detection.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Xueqiang Ji, Jianying Yue, Xiaohui Qi, Zuyong Yan, Shan Li, Chao Lu, Zhitong Li, Zeng Liu, Song Qi, Xu Yan, Jinjin Wang, Shuang Wang, Peigang Li, Weihua Tang
Summary: In this study, stable and tunable electron concentration in fl-Ga2O3 homoepitaxial epitaxial films was achieved by using metal-organic chemical vapor deposition (MOCVD) on Fe-doped (010)-oriented fl-Ga2O3 substrates. The electrical properties of the films were found to vary depending on the concentration of Si ions incorporated during the growth process. The results suggest that stable and tunable electron concentration is crucial for optimizing high-power electronic devices based on fl-Ga2O3.
Article
Nanoscience & Nanotechnology
Zhaoying Xi, Zeng Liu, Lili Yang, Kai Tang, Lei Li, Gaohui Shen, Maolin Zhang, Shan Li, Yufeng Guo, Weihua Tang
Summary: In this study, a solar-blind UV photodetector based on a La2O3/e-Ga2O3 heterojunction was successfully fabricated, which possesses excellent reliability and sensitivity for flame detection without interference from other signals. The photodetector exhibits a self-powered photocurrent of 1.4 nA at zero bias due to the photovoltaic effect formed by the space charge region across the junction interface. Furthermore, the photodetector achieves a high photo-to-dark current ratio of 2.68 x 10(4), a high specific detectivity of 2.31 x 10(11) Jones, and a large responsivity of 1.67 mA/W under 254 nm UV light illumination and at a bias of 5 V. Additionally, the La2O3/e-Ga2O3 heterojunction photodetector can rapidly respond to flames in milliseconds without any applied biases. Based on these performances, this novel heterojunction is expected to be a candidate for future energy-efficient fire detection.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Applied
Gaohui Shen, Zeng Liu, Chee-Keong Tan, Mingming Jiang, Shan Li, Yufeng Guo, Weihua Tang
Summary: A solar-blind UV photodetector array based on a metalorganic chemical vapor deposition-grown beta-Ga2O3 thin film is fabricated for optical communication application. The device demonstrates high performance with a significant photo-to-dark current ratio, high responsivity, high external quantum efficiency, high specific detectivity, and fast response time. The array shows good spectral selectivity and low background noise, enabling effective outputting of information signals in optical communication.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Environmental
Yinhua Cui, Qingshan Shi, Zeng Liu, Jingchun Lv, Chao Wang, Xiaobao Xie, Shaohui Zhang
Summary: In this study, a new approach is proposed to prepare flexible MXene/biomass/chitosan aerogel (MBC) electrodes with pseudo-capacitive properties through electro-static self-assembly and hydrothermal methods. The MBC-6 electrode, annealed by lyophilization, exhibits a volumetric specific capacitance of 1801.4 mF/cm3 and an ultra-high volume energy density of 33.4 Wh/L. This research presents a plausible approach for creating energy storage devices with high energy density and voltage window.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Physics, Multidisciplinary
Maolin Zhang, Wanyu Ma, Qiong Zhang, Ang Bian, Zeng Liu, Lili Yang, Shan Li, Yufeng Guo, Weihua Tang
Summary: In this study, a heterojunction photodetector combining MAPbBr3 and GaN was constructed, and its detection capabilities were examined. The results demonstrated superior performance, including high rectification ratio and photo-to-dark current ratio. Additionally, the characteristics of the photodetector and possible methods for further performance enhancements were discussed.
Article
Engineering, Multidisciplinary
Gaohui Shen, Zeng Liu, Kai Tang, Shulin Sha, Lei Li, Chee-Keong Tan, Yufeng Guo, Weihua Tang
Summary: This study introduces an 8x8 Ga2O3 solar-blind ultraviolet photodetector array with high photo-response performance and uniform responsivity, which is of great significance for developing Ga2O3-based optoelectronic device applications.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Song Qi, Jiahang Liu, Jianying Yue, Xueqiang Ji, Jiaying Shen, Yongtao Yang, Jinjin Wang, Shan Li, Zhenping Wu, Weihua Tang
Summary: In this work, a graphene/beta-Ga2O3/Ag asymmetric Schottky junction photodetector was constructed to address the issue of elevated dark currents in existing graphene/Ga2O3 devices. By taking advantage of the asymmetric structure design to suppress dark current and the transparent graphene electrode to increase carrier collection efficiency, the device achieved outstanding responsivity, detectivity, external quantum efficiency, and response time. Importantly, it exhibited low dark current and high light-to-dark ratio. Overall, the graphene/beta-Ga2O3/Ag asymmetric Schottky junction photodetector has considerable potential as a deep ultraviolet detector.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Optics
Xu Qiang, Yang Lili, Liu Zeng, Zhang Maolin, Li Shan, Tang Weihua
Summary: In this study, an Ag-NP composite amorphous Ga2O3 film DUV PD is prepared by room temperature magnetron sputtering technology. The PD exhibits excellent photodetection performance with low dark current, high PDCR, and enhanced UV light absorption. The introduction of Ag-NPs scatters more incident light into the Ga2O3 film layer, leading to increased absorption of UV light and a significant increase in photocurrent. This is further enhanced by the generation of hot carriers by Ag-NPs, which allows hot electrons to overcome the Schottky barriers and increase the photocurrent. The formation of Schottky barriers between Ag-NPs and Ga2O3 films also helps reduce the dark current in the amorphous Ga2O3. This study provides a viable solution to DUV PDs with low cost, dark current, and high PDCR.
ACTA OPTICA SINICA
(2023)
