- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
A review of the most recent progresses of state-of-art gallium oxide power devices
摘要： Until very recently, gallium oxide (Ga2O3) has aroused more and more interests in the area of power electronics due to its ultra-wide bandgap of 4.5–4.8 eV, estimated critical field of 8 MV/cm and decent intrinsic electron mobility limit of 250 cm2/(V·s), yielding a high Baliga’s figures-of-merit (FOM) of more than 3000, which is several times higher than GaN and SiC. In addition to its excellent material properties, potential low-cost and large size substrate through melt-grown methodology also endows β-Ga2O3 more potential for future low-cost power devices. This article focuses on reviewing the most recent advances of β-Ga2O3 based power devices. It will be starting with a brief introduction to the material properties of β-Ga2O3 and then the growth techniques of its native substrate, followed by the thin film epitaxial growth. The performance of state-of-art β-Ga2O3 devices, including diodes and FETs are fully discussed and compared. Finally, potential solutions to the challenges of β-Ga2O3 are also discussed and explored.
关键词： power electronics,power devices,gallium oxide
更新于2025-09-23 15:22:29
-
Heteroepitaxial growth of thick <i>α</i> -Ga <sub/>2</sub> O <sub/>3</sub> film on sapphire (0001) by MIST-CVD technique
摘要： The 8 μm thick single-crystalline α-Ga2O3 epilayers have been heteroepitaxially grown on sapphire (0001) substrates via mist chemical vapor deposition technique. High resolution X-ray diffraction measurements show that the full-widths-at-half-maximum (FWHM) of rocking curves for the (0006) and (10-14) planes are 0.024° and 0.24°, and the corresponding densities of screw and edge dislocations are 2.24 × 106 and 1.63 × 109 cm?2, respectively, indicative of high single crystallinity. The out-of-plane and in-plane epitaxial relationships are [0001] α-Ga2O3//[0001] α-Al2O3 and [11-20] α-Ga2O3//[11-20] α-Al2O3, respectively. The lateral domain size is in micron scale and the indirect bandgap is determined as 5.03 eV by transmittance spectra. Raman measurement indicates that the lattice-mismatch induced compressive residual strain cannot be ruled out despite the large thickness of the α-Ga2O3 epilayer. The achieved high quality α-Ga2O3 may provide an alternative material platform for developing high performance power devices and solar-blind photodetectors.
关键词： chemical vapor deposition,ultra-wide bandgap semiconductor,gallium oxide,epitaxy
更新于2025-09-23 15:22:29
-
Current transport mechanism of Mg/Au ohmic contacts to lightly doped n-type <i>β</i> -Ga <sub/>2</sub> O <sub/>3</sub>
摘要： The carrier transport mechanism of Mg/Au ohmic contact for lightly doped β-Ga2O3 is investigated. An excellent ohmic contact has been achieved when the sample was annealed at 400 °C and the specific contact resistance is 4.3 × 10?4 Ω·cm2. For the annealed sample, the temperature dependence of specific contact resistance is studied in the range from 300 to 375 K. The specific contact resistance is decreased from 4.3 × 10?4 to 1.59 × 10?4 Ω·cm2 with an increase of test temperature. As combination with the judge of E00, the basic mechanism of current transport is dominant by thermionic emission theory. The effective barrier height between Mg/Au and β-Ga2O3 is evaluated to be 0.1 eV for annealed sample by fitting experimental data with thermionic emission model.
关键词： effective barrier height,beta-gallium oxide,Mg/Au,ohmic contact,thermionic emission theory
更新于2025-09-23 15:22:29
-
Design and Mechanism of Embedding Specific Carbon Nanotubes in Sputtered Sandwiched InGaZnO Thin Film Transistors
摘要： Amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) with high mobility are highly desirable to achieve high-speed operation in active-matrix displays and large-area sensors. Only a few works provided potential solutions. In this work, we have embedded carbon nanotubes (CNTs) into sputtered a-IGZO film to form a-IGZO/CNT/a-IGZO (ACA) sandwiched channel. In the ACA channel, the CNT percolation networks connected by the a-IGZO film work as high-speed carrier paths to enable faster transport of carriers during the on state while it does not degrade the leakage performance during the off state. The type and the embedding location of the CNT percolation network are critical to determine the ACA device performance, which is analyzed and verified by experiment and simulation. The optimum ACA design has approximately doubled the mobility and the on current density of the TFT. The design owns relatively better uniformity and provides a high-speed TFT solution for the advanced electronics.
关键词： mobility,amorphous indium gallium zinc oxide,carbon nanotube,thin film transistor,sandwiched structure
更新于2025-09-23 15:22:29
-
Selected <sup>68</sup>Ga-siderophores versus <sup>68</sup>Ga-colloid and <sup>68</sup>Ga-citrate: biodistribution and small animal imaging in mice
摘要： Background—68Ga-triacetylfusarinine C (TAFC) and 68Ga-ferrioxamine E (FOXE) show great potential to be used as highly sensitive and selective tracers for Aspergillus infection imaging. Here we report on a comparison of the ex vivo biodistribution and small animal imaging of 68Ga-TAFC and 68Ga-FOXE versus 68Ga-colloid and 68Ga-citrate as unspecific control in mice. Methods—The radiochemical purity of tested 68Ga labelled tracers was determined by RP-HPLC or ITLC-SG. Ex vivo biodistribution was studied in normal DBA/2 mice 30 min and 90 min p.i. Static and dynamic imaging were performed using μPET/CT. Results—68Ga-TAFC and 68Ga-FOXE showed rapid renal excretion and low blood values even 90 min p.i. 68Ga-TAFC showed almost no retention in other organs while 68Ga-FOXE displayed some uptake in gastrointestinal tract. 68Ga-colloid and 68Ga-citrate revealed significantly different ex vivo biodistribution. 68Ga-colloid showed pronounced radioactivity retention in the liver, while 68Ga-citrate displayed high blood values and significant retention of radioactivity in highly perfused organs. Conclusions—From the results, both 68Ga-TAFC and 68Ga-FOXE have excellent and significantly different in vivo behaviour compared to 68Ga-colloid and 68Ga-citrate. 68Ga-TAFC in particular confirmed its great potential use as a specific tracer for Aspergillus infection imaging.
关键词： gallium-68,citrate,colloid,siderophores,aspergillosis,μPET imaging
更新于2025-09-23 15:22:29
-
Photodeposition of palladium nanoparticles on a porous gallium nitride electrode for nonenzymatic electrochemical sensing of glucose
摘要： A nonenzymatic electrochemical glucose sensor is described that was obtained by in situ photodeposition of high-density and uniformly distributed palladium nanoparticles (PdNPs) on a porous gallium nitride (PGaN) electrode. Cyclic voltammetric and chronoamperometric techniques were used to characterize the performance of the modified electrode toward glucose. In 0.1 M NaOH solution, it has two linear detection ranges, one from 1 μM to 1 mM, and another from 1 to 10 mM, and the detection limit is 1 μM. The electrode is repeatable, highly sensitive, fast and long-term stable. It was applied to the quantitation of serum glucose where it displayed accurate current responses.
关键词： Electrochemical sensing,Gallium nitride,Photodeposition,Glucose detection,Palladium nanoparticles,Porous materials
更新于2025-09-23 15:22:29
-
Application of Fluorine-18-Deoxyglucose Positron Emission Tomography and Gallium Scan for Assessment in a Patient With Adult-Onset Still's Disease
摘要： A 53-year-old female patient suffered from pain in almost her entire body, particularly the joints. Chest computed tomography revealed multiple lymphadenopathies over cervical, mediastinal, and axillary areas. A fluorine-18-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed increased FDG uptake in many lymph nodes and the spleen. Lymphoma was suspected. However, the result of a biopsy showed no malignancy, and the gallium-67 citrate scan showed no gallium-avid tumor throughout the whole body. Adult-onset Still's disease was diagnosed and the patient responded well to steroid therapy. The follow-up PET/CT six months later showed complete remission of the FDG-avid lesions seen in the previous PET/CT. Our study suggests that FDG PET/CT combined with gallium-67 scan may be helpful in diagnosing patients with adult-onset Still's disease. In addition, the use of FDG PET/CT alone may be useful for the evaluation of disease distribution, disease activity, and therapeutic response.
关键词： fluorine-18-deoxyglucose,Adult-onset Still's disease,positron emission tomography/computed tomography,gallium-67
更新于2025-09-23 15:22:29
-
Half-metallic ferromagnetic behavior in (Ga, Cr)N and (Ga, Cr, V)N compounds for spintronic technologies: Ab-initio and Monte Carlo methods
摘要： In this article, we investigate the magnetic- and electronic-proprieties of GaN doped with simple- and double-impurities utilizing Ab-initio and Monte Carlo studies. We have predicted that (Ga, Cr)N and (Ga, Cr, V)N compounds exhibit ferromagnetic- and halfmetallic-behavior with 100% spin-polarization at the Fermi-level. Moreover, we have found that Ga1-xCrxN and Ga1-2xCrxVxN (x = 0.04, 0.05 and 0.06) show a 2nd order ferromagnetic transition and that their Tc is above room temperature. These predictions make (Ga, Cr)N and (Ga, Cr, V)N compounds strong-candidates for spintronic-technologies.
关键词： Ab-initio calculations,Monte Carlo method,Diluted magnetic semiconductors,Spintronic,Gallium Nitride
更新于2025-09-23 15:22:29
-
Gas sensing performance of GaOOH and β-Ga<sub>2</sub>O<sub>3</sub> synthesized by Hydrothermal method: A comparison
摘要： Gallium Oxy Hydrate (GaOOH) and β-Ga2O3 nanostructures in submicron scale have been synthesized at low temperature by surfactant-free hydro-thermal method. First, GaOOH has been synthesized using Gallium nitrate anhydrate, Ammonium hydroxide as precursors and double distilled water as solvent. As obtained GaOOH powders have been characterized by XRD, FE–SEM, UV–VIS, Thermo Gravimetric Analysis, I-V characteristics and BET surface analysis in order to reveal their structural, morphological, optical, thermal, electrical and surface properties. FE-SEM micrographs confirm the rod like and needle like morphologies of GaOOH and β- Ga2O3 samples, respectively. Porous nature of the samples observed through BET and BJH analyses. Synthesized GaOOH and β-Ga2O3 powders have been subjected to room temperature CO2 gas sensing in the range, 2000 ppm – 10000 ppm. GaOOH showed quick response of 80 s and fast recovery of 129 s at 8000 ppm while β-Ga2O3 showed quick response of 52 s at 8000 ppm and faster recovery of 98 s at 4000 ppm. Also, the repeatability studies were done for GaOOH and β-Ga2O3 films by exposing to different CO2 concentrations for a period of 6 consecutive days. β-Ga2O3 showed enhanced CO2 sensing response than that of GaOOH due to its better structural, electrical, morphological and surface properties.
关键词： Gallium Oxide (Ga2O3),Gallium Oxide Hydroxide (GaOOH),Hydrothermal method,Characterization,Room temperature CO2 sensing
更新于2025-09-23 15:21:21
-
Multi- and single-step in-situ microwave annealing as low-thermal-budget techniques for solution-processed indium–gallium–zinc oxide thin films
摘要： In this study, low-thermal-budget in-situ microwave annealing of solution-processed indium–gallium–zinc oxide (IGZO) thin films was investigated as a potential alternative to the conventional high-thermal-budget annealing process. The low-temperature baking and high-temperature post-deposition annealing of the solution-processed IGZO film were continuously performed using the same microwave equipment, leading to a reduced heat treatment processing time and temperature. We compared the electrical characteristics of IGZO thin film transistors (TFTs) produced using single- and multi-step in-situ microwave annealing methods with those of TFTs manufactured via the conventional annealing method and found that the proposed single-step microwave annealing method yielded TFTs with electrical characteristics better than those of the TFTs fabricated using the multi-step and conventional annealing methods. In addition, the reliability was evaluated by conducting positive and negative gate bias stress tests, in which the IGZO TFTs manufactured using the proposed heat treatment method proved superior to those fabricated via the conventional heat treatment method. We investigated the effects of heat treatment on the composition and energy band structures of the IGZO films by performing X-ray photoelectron spectroscopy analysis and found that the proposed in-situ microwave annealing method is more effective than the conventional method in solution processing.
关键词： low thermal budget,indium-gallium-zinc oxide,Microwave,solution process
更新于2025-09-23 15:21:21