ORCID Profile
0000-0002-4479-4485
Current Organisation
Anhui University
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Publisher: AIP Publishing
Date: 16-10-2023
DOI: 10.1063/5.0172026
Publisher: Wiley
Date: 24-02-2016
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2018
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 08-2014
Publisher: IOP Publishing
Date: 07-09-2021
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 05-2022
Publisher: IOP Publishing
Date: 29-10-2018
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 04-2023
Publisher: IEEE
Date: 05-2019
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 12-2015
Publisher: IEEE
Date: 12-2015
Publisher: IEEE
Date: 05-2017
Publisher: AIP Publishing
Date: 05-07-2021
DOI: 10.1063/5.0054612
Abstract: An AlGaN/GaN metal-heterostructure-metal (MHM) ultraviolet (UV) photodetector employing lateral Schottky contacts was fabricated and characterized at different temperatures. As the temperature increased from 25 to 250 °C, the photoresponsivity of the MHM photodetector increased 3.5 times. This was attributed to the spontaneous-polarization-induced spatial separation of the photogenerated electrons and holes and the increased optical absorption at higher temperatures. Meanwhile, the decay time constant of the photocurrent became approximately three orders of magnitude smaller. With the enhanced photoresponsivity and the decreased response time constant, kilohertz optical switching of the MHM photodetector was recorded at 250 °C. The AlGaN/GaN MHM photodetector, sharing the same GaN-on-Si electronics platform, provides an applicable candidate for an all-GaN integrated UV sensing and lifying system for high-temperature applications.
Publisher: AIP Publishing
Date: 27-02-2023
DOI: 10.1063/5.0140725
Abstract: This work studies the conductivity modulation in the vertical GaN-on-GaN PiN diode (PND) under high current density and its impact on surge current capability. Thanks to the direct-bandgap of GaN, the junction temperature at different current densities could be characterized by both photo-luminescence and electro-luminescence measurements. The junction temperature rises from 300 K at ∼0.1 kA/cm2 to 620 K at ∼9.0 kA/cm2 with emission peaks shifted from 3.38 to 3.21 eV. Meanwhile, the electro-thermal behavior of the vertical GaN PND shows that the hole concentration in p-GaN is increased due to self-heating, leading to enhanced conductivity modulation and negative temperature-dependence of ON-resistance, which is desirable for surge current capability. The heat accumulation in GaN under surge current condition could be suppressed by the enhanced conductivity modulation. The surge energy density can reach ∼200 J/cm2 in the GaN PND, showing the potential of vertical GaN-on-GaN power devices in the high electro-thermal-ruggedness application.
Publisher: IEEE
Date: 05-2015
Publisher: Wiley
Date: 17-02-2016
Abstract: In this work, the Schottky‐on‐heterojunction light‐emitting diodes (SoH‐LED) are monolithically integrated with the AlGaN/GaN high‐electron‐mobility transistors (HEMT) on an AlGaN/GaN‐on‐Si platform commonly used for GaN lateral electronic devices. The on‐chip electro‐optic modulation is realized in a single device fabricated using HEMT‐compatible process. Also, SoH‐LED arrays are fabricated to demonstrate the on‐chip addressable functionality with each SoH‐LED pixel in the array in idually controlled by the integrated HEMT. High‐resolution micro‐scale SoH‐LED seven‐segment displays are demonstrated to show the potential of using SoH‐LEDs as a robust alternative for micro flat‐panel displays. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Publisher: IEEE
Date: 12-2016
Publisher: IEEE
Date: 12-2014
Publisher: MDPI AG
Date: 25-12-2020
DOI: 10.3390/EN14010082
Abstract: A new silicon carbide (SiC) planar-gate insulated-gate bipolar transistor (IGBT) is proposed and comprehensively investigated in this paper. Compared to the traditional SiC planar-gate IGBT, the new IGBT boasts a much stronger injection enhancement effect, which leads to a low on-state voltage (VON) approaching the SiC trench-gate IGBT. The strong injection enhancement effect is obtained by a heavily doped carrier storage layer (CSL), which creates a hole barrier under the p-body to hinder minority carriers from being extracted away through the p-body. A p-shield is located at the bottom of the CSL and coupled to the p-body of the IGBT by an embedded p-MOSFET (metal-oxide-semiconductor field effect transistors). In off-state, the heavily doped CSL is shielded by the p-MOSFET cl ed p-shield. Thus, a high breakdown voltage is maintained. At the same time, owing to the planar-gate structure, the proposed IGBT does not suffer the high oxide field that threatens the long-term reliability of the trench-gate IGBT. The turn-off characteristics of the new IGBT are also studied, and the turn-off energy loss (EOFF) is similar to the conventional planar-gate IGBT. Therefore, the new IGBT achieves the benefits of both the conventional planar-gate IGBT and the trench-gate IGBT, i.e., a superior VON-EOFF trade-off and a low oxide field.
Publisher: AIP Publishing
Date: 04-2020
DOI: 10.1063/5.0005648
Abstract: Solar to fuel energy conversion is one of the momentous topics nowadays considering the urgent demand for clean energy supplies. In this work, the tunable electronic and optical properties of III-nitride/ZnO 2D/2D heterostructures (including GaN/ZnO, AlN/ZnO, and GaN/AlN) by strain engineering were investigated by first-principles calculations. The studied heterostructures feature a small interlayer distance, with the cation of one layer directly above the anion of the other layer, and vice versa. This leads to a strong binding energy and interlayer coupling across the heterostructure. The built-in field induced by the charge redistribution facilitates the photoexcited carrier migration, which is beneficial to the photocatalytic water splitting application. The stable III-nitride/ZnO heterostructures exhibit decent band edge positions with biaxial strain engineering and feature an enhancement of optical absorption under tensile strain. Our results indicate that the III-nitride/ZnO 2D/2D heterostructures are promising photocatalysts for solar to hydrogen generation by water splitting.
Publisher: AIP Publishing
Date: 02-03-2015
DOI: 10.1063/1.4914455
Abstract: In this work, by using an on-chip integrated Schottky-on-heterojunction light-emitting diode (SoH-LED) which is seamlessly integrated with the AlGaN/GaN high electron mobility transistor (HEMT), we studied the effect of on-chip light illumination on the de-trapping processes of electrons from both surface and bulk traps. Surface trapping was generated by applying OFF-state drain bias stress, while bulk trapping was generated by applying positive substrate bias stress. The de-trapping processes of surface and/or bulk traps were monitored by measuring the recovery of dynamic on-resistance Ron and/or threshold voltage Vth of the HEMT. The results show that the recovery processes of both dynamic Ron and threshold voltage Vth of the HEMT can be accelerated by the on-chip SoH-LED light illumination, demonstrating the potentiality of on-chip hybrid opto-HEMTs to minimize the influences of traps during dynamic operation of AlGaN/GaN power HEMTs.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 2019
Publisher: American Chemical Society (ACS)
Date: 03-05-2019
Abstract: In a resource-constrained world of an estimated 10 billion people in 2050 with the same material aspirations of today's high-income nations, there is no question: The future economy will need to be circular. From a policy perspective, the question is whether averting catastrophic environmental impacts through an accelerated transition to a global circular economy can also deliver sustained growth and jobs. The adoption of circular economy measures will have a range of effects on both domestic and foreign supply chains. Multiregional input-output (MRIO) analysis models the interdependencies between industries and within and between countries as well as between intermediate and final goods producers and consumers. It provides a useful toolbox for assessing social, environmental, and economy-wide impacts of the adoption of the circular economy. We project the MRIO database EXIOBASE to 2030 on the basis of the exogenously given parameters of the International Energy Agency's Energy Technology Perspective (IEA ETP) 6-degree scenario. We compare this business-as-usual (BAU) scenario and an alternative circular economy scenario. The circular economy scenario considers more recycling, reducing (material efficiency increase), repair, and reuse in relation to the BAU scenario. The adoption of circular economy measures has erse impacts on the economy and environmental pressures. Global material extraction is reduced by about 10% compared to the baseline, while the impact on employment is small but positive. In particular, the shift from resource extracting sectors to the service sector will provide more opportunities for high-skilled and female workers.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 2018
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2017
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2016
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 10-2017
Publisher: IOP Publishing
Date: 13-06-2018
Publisher: AIP Publishing
Date: 08-2020
DOI: 10.1063/5.0012685
Abstract: The below bandgap optical transitions of an aluminum nitride (AlN) crystal grown on a tungsten (W) substrate by physical vapor transport (PVT) are investigated by below-bandgap-excited photoluminescence (PL) spectroscopy and first-principles calculations. Oxygen (O) is the only impurity in the AlN-on-W crystal grown by PVT. By analyzing the excitation-power-, excitation-photon-energy-, and temperature-dependence of the PL spectra, the emission peaks of defect complexes involving aluminum vacancy (VAl) and substitutional oxygen (ON) with different spatial and atomic configurations, i.e., VAl–ON and VAl–2ON with ON featuring axial or basal configurations, are identified. It is revealed that two different charging states coexist in thermal equilibrium for each configuration of VAl–ON complexes. The optical transitions between the conduction band and (VAl–ON)2− and/or (VAl–2ON)1− contribute the UV emissions and those between the valence band and (VAl–ON)1− or (VAl–2ON)0 contribute the red emissions.
Publisher: AIP Publishing
Date: 27-07-2020
DOI: 10.1063/5.0011831
Abstract: In this work, the breakdown characteristics and the electroluminescence (EL) spectra of a Schottky-metal -GaN/AlGaN/GaN device under forward bias were investigated at different temperatures. The failure of the metal -GaN junction, which was caused by electron transport in the p-type Schottky junction, was identified as the first step in the device breakdown process. The breakdown voltage increased with higher temperatures. Under a forward bias of 8 V, the intensity of the EL emission increased more than two orders of magnitude, while the current increased by a factor of 4 as the temperature increased from 0 °C to 200 °C. This unambiguously demonstrated thermally enhanced hole injection at the Schottky-metal -GaN interface. We proposed that more electrons were annihilated by the thermally enhanced hole injection, resulting in the positive temperature dependence of the device breakdown.
Publisher: IOP Publishing
Date: 09-04-2018
Publisher: IEEE
Date: 10-2016
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 08-2018
Publisher: American Chemical Society (ACS)
Date: 17-10-2021
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 09-2019
Publisher: IEEE
Date: 06-2016
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 08-2018
Publisher: AIP Publishing
Date: 21-07-2014
DOI: 10.1063/1.4890238
Abstract: We report that a simple metal-AlGaN/GaN Schottky diode is capable of producing GaN band-edge ultraviolet emission at 3.4 eV at a small forward bias larger than ∼2 V at room temperature. Based on the surface states distribution of AlGaN, a mature impact-ionization-induced Fermi-level de-pinning model is proposed to explain the underlying mechanism of the electroluminescence (EL) process. By experimenting with different Schottky metals, Ni/Au and Pt/Au, we demonstrated that this EL phenomenon is a “universal” property of metal-AlGaN/GaN Schottky diodes. Since this light-emitting Schottky diode shares the same active structure and fabrication processes as the AlGaN/GaN high electron mobility transistors, straight-forward and seamless integration of photonic and electronic functional devices has been demonstrated on doping-free III-nitride heterostructures. Using a semitransparent Schottky drain electrode, an AlGaN/GaN high electron mobility light-emitting transistor is demonstrated.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 2023
Publisher: IEEE
Date: 12-2015
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 15-12-2016
Publisher: IOP Publishing
Date: 08-05-2019
Publisher: AIP Publishing
Date: 04-07-2022
DOI: 10.1063/5.0094484
Abstract: Understanding the occurrence of charge density wave (CDW) states in quasi-one-dimensional (quasi-1D) transition metal trichalcogenides has attracted substantial research interest. Here, we report the systematic control of hysteretic transitions in quasi-1D TiS3 microribbons by changing the thickness and the cooling rate. Two distinguished resistance hysteresis loops are observed at a high temperature of ∼290 K and a low temperature of ∼60 K, respectively. In addition, two hysteretic transitions exhibit different behaviors under the external perturbations, in which the high temperature hysteretic transition is sensitive to TiS3 microribbons thickness, while the low temperature hysteretic transition is probably related to the CDW state and is robust against external perturbations. Our findings will offer a new frontier of exploration of the hysteretic transitions in the quasi-1D transition metal trichalcogenides.
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