Article
Chemistry, Physical
Qiao Xu, Xianglei Liu, Qingyang Luo, Yang Tian, Chunzhuo Dang, Haichen Yao, Chao Song, Yimin Xuan, Junming Zhao, Yulong Ding
Summary: This study proposes an eco-friendly SiC ceramic based on loofah-derived materials for efficient solar thermal energy storage. After impregnation with NaCl-NaF eutectics, the ceramic demonstrates broadband solar absorption, rapid thermal transport, and compact latent heat storage.
ENERGY STORAGE MATERIALS
(2022)
Article
Crystallography
Maolin Zhang, Lei Wang, Kemeng Yang, Jiafei Yao, Weihua Tang, Yufeng Guo
Summary: The on-state properties and breakdown characteristics of the gallium oxide-on-silicon carbide metal-oxide-semiconductor field-effect transistor (MOSFET) were investigated using the technology computer-aided design (TCAD) approach. Compared to a full gallium oxide MOSFET, the lattice temperature of the gallium oxide-on-silicon carbide MOSFET was reduced by almost 100°C due to the high thermal conductivity of silicon carbide. However, an unoptimized gallium oxide-on-silicon carbide MOSFET showed a breakdown voltage degradation of over 40%. By optimizing the device structure, the breakdown voltage degradation of the gallium oxide-on-silicon carbide MOSFET was significantly reduced.
Article
Chemistry, Physical
Q. Xu, X. Liu, Q. Luo, Y. Song, H. Wang, M. Chen, Y. Xuan, Y. Li, Y. Ding
Summary: This study presents a strategy for ultrafast solar and thermal energy storage based on biomorphic SiC skeletons embedded NaCl-KCl molten salts, achieving a record-high thermal conductivity through replicating cellular structure of oak wood. By decorating TiN nanoparticles on SiC skeletons, the solar absorptance is enhanced, enabling designed composites to have bifunctional capabilities of harvesting both thermal energy and solar energy very rapidly.
MATERIALS TODAY ENERGY
(2021)
Article
Materials Science, Multidisciplinary
Dan Kuang, Adrian H. Kitai, Zhinong Yu
Summary: Zinc Oxide (ZnO) and Silicon Carbide (SiC) are highly promising semiconductors with wide bandgaps, and their heterostructures have potential for the next generation of optoelectronics technologies. The optoelectric properties of ZnO nanowires and n-type 4H-SiC heterojunction UV photodetectors were studied and compared for different SiC doping concentrations. A high-performance UV photodetector based on a ZnO/4H-SiC heterojunction with a high SiC doping concentration of 10(18)/cm(3) was successfully fabricated, showing improved optoelectronic performance compared to other devices. The heterojunction structure and energy band bending in the ZnO/SiC interface facilitate spatial separation of electron-hole pairs and efficient transport of charge carriers, enhancing photocurrent and enabling quick time response.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Myeong-Cheol Shin, Young-Jae Lee, Dong-Hyeon Kim, Seung-Woo Jung, Michael A. Schweitz, Weon Ho Shin, Jong-Min Oh, Chulhwan Park, Sang-Mo Koo
Summary: In this study, static induction transistors (SITs) with beta gallium oxide (beta-Ga2O3) channels were grown on a p-epi silicon carbide (SiC) layer via radio frequency sputtering. The Ga2O3 films were treated with UV/ozone, producing reduced oxygen vacancies, lower surface roughness and resistivity, and higher mobility. The UV/O-3-treated SITs exhibited significantly higher drain current and on/off ratio compared to non-treated control devices.
Article
Nanoscience & Nanotechnology
Yiwen Song, Praneeth Ranga, Yingying Zhang, Zixuan Feng, Hsien-Lien Huang, Marco D. Santia, Stefan C. Badescu, C. Ulises Gonzalez-Valle, Carlos Perez, Kevin Fern, Robert M. Lavelle, David W. Snyder, Brianna A. Klein, Julia Deitz, Albert G. Baca, Jon-Paul Maria, Bladimir Ramos-Alvarado, Jinwoo Hwang, Hongping Zhao, Xiaojia Wang, Sriram Krishnamoorthy, Brian M. Foley, Sukwon Choi
Summary: This study investigates the thermal conductivity of heteroepitaxial beta-Ga2O3 films, and finds that the thermal conductivity is strongly influenced by film thickness, crystallinity, and substrate offcut angles. Additionally, the thermal conductivity of ((2) over bar 01)-oriented beta-(AlxGal)(2)O-3 thin films grown via MOVPE was characterized, with results showing lower conductivity due to phonon-alloy disorder scattering. These findings provide fundamental insights for the development of beta-Ga2O3 electronic and optoelectronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Yuxin Deng, Ziqi Yang, Tongling Xu, Huaxing Jiang, Kar Wei Ng, Chao Liao, Danni Su, Yanli Pei, Zimin Chen, Gang Wang, Xing Lu
Summary: Due to the difficulty of p-type doping in beta-Ga2O3, the NiO/beta-Ga2O3 heterojunction is considered as a promising candidate for bipolar devices. In this study, the band alignment and electrical properties of NiO/beta-Ga2O3 heterojunctions with different beta-Ga2O3 orientations were comparatively studied. It was found that there is a type-II band alignment between NiO and beta-Ga2O3, and the valence band offsets and conduction band offsets vary with different substrate orientations. The influence of substrate orientations on the properties of NiO/beta-Ga2O3 heterojunctions is of great importance for the design and optimization of beta-Ga2O3-based heterojunction devices.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Xiaoxu Huang, Emina Hara, Hisashi Sugime, Suguru Noda
Summary: A multifunctional MoOx layer was utilized to enhance the size and performance of CNT/Si heterojunction solar cells, providing a facile route for practical application.
Article
Chemistry, Analytical
Ruoyu Wang, Jingwei Guo, Chang Liu, Hao Wu, Zhiyong Huang, Shengdong Hu
Summary: In this paper, a new 650V 4H-SiC trench MOSFET with HJD and double CSLs is proposed and studied, which can suppress the turn-on of parasitic body diode, improve the transistor performance, and reduce the on-state resistance and gate-drain capacitance by using CSLs with different doping concentrations.
Article
Materials Science, Multidisciplinary
Min-Yeong Kim, Hee-Jae Lee, Dong-Wook Byun, Seung-Woo Jung, Myeong-Cheol Shin, Michael A. Schweitz, Sang-Mo Koo
Summary: This study analyzes the effects of annealing on the electrothermal properties of Gallium Oxide (Ga2O3) thin films. The results show that the annealed sample has high current performance with a slight temperature rise.
Article
Engineering, Electrical & Electronic
Abderrahmane Boughelout, Roberto Macaluso, Isodiana Crupi, Bartolomeo Megna, Amer Brighet, Mohamed Trari, Mohamed Kechouane
Summary: The structural and photoelectrical properties of AZO/SiC heterojunctions fabricated by pulsed laser deposition were studied, showing that SiC layers have 3C-SiC phase and AZO films exhibit hexagonal wurtzite structure with excellent material properties. Both heterojunctions exhibited diode behavior under dark and white light, with a noticeable superiority for the AZO/SiC/n-Si device under illumination.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Ceramics
Xiaoyang Ji, Zhe Cheng, Ella K. Pek, David G. Cahill
Summary: In this study, the thermal conductance of the oxide layer and the thermal conductivity of SiC/SiC composites were mapped with high spatial resolution using time-domain thermoreflectance (TDTR). It was found that the dominant source of noise in the measurements was the input noise of the preamplifier under low laser powers or small integration time constants. The thermal conductance of the oxide on the fiber region was lower than that on the matrix due to slight differences in thickness and thermal conductivity.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Physical
Chao-Ching Chiang, Xinyi Xia, Jian-Sian Li, Fan Ren, S. J. Pearton
Summary: The 8-polytype of Ga2O3 is a promising material for next generation power electronics and solar-blind UV photodetectors due to its high critical electric field strength and ability to be grown as large diameter single crystals. Dry etching is being focused on for patterning such devices, but it may cause surface modification and damage to the material. This study demonstrates that dry etch damage in 8-Ga2O3 leads to a reduction in near-surface carrier concentration, affecting device parameters like on-state resistance and introducing trap-assisted space-charge-limited conduction in the damaged layers.
APPLIED SURFACE SCIENCE
(2023)
Article
Energy & Fuels
Adrien Danel, Nicolas Chaugier, Jordi Veirman, Renaud Varache, Mickael Albaric, Etienne Pihan
Summary: This study demonstrates that by using gallium-doped wafers, it is possible to achieve efficiency in front-junction p-type cells comparable to rear-junction bifacial n-type cells without process alterations.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Fumiaki Amano, Mizuki Ishimaru
Summary: Photocatalytic non-oxidative coupling of methane (photo-NOCM) has very low efficiency without oxidants, while photocatalytic dehydrogenative coupling of methane (photo-DHCM) can proceed efficiently in the presence of water vapor. Metal co-catalysts supported on Ga2O3 play a crucial role in the production of C2H6 and H2 in photo-DHCM, with Au/Ga2O3 exhibiting the highest C2H6 production rate and selectivity.
Article
Chemistry, Physical
Myeong-Cheol Shin, Young-Jae Lee, Dong-Hyeon Kim, Seung-Woo Jung, Michael A. Schweitz, Weon Ho Shin, Jong-Min Oh, Chulhwan Park, Sang-Mo Koo
Summary: In this study, static induction transistors (SITs) with beta gallium oxide (beta-Ga2O3) channels were grown on a p-epi silicon carbide (SiC) layer via radio frequency sputtering. The Ga2O3 films were treated with UV/ozone, producing reduced oxygen vacancies, lower surface roughness and resistivity, and higher mobility. The UV/O-3-treated SITs exhibited significantly higher drain current and on/off ratio compared to non-treated control devices.
Article
Chemistry, Physical
Seung-Woo Jung, Myeong-Cheol Shin, Michael A. Schweitz, Jong-Min Oh, Sang-Mo Koo
Summary: The physical and electrical characteristics of an AlN/4H-SiC Schottky barrier diode-based temperature sensor annealed in various gas atmospheres were investigated in this study. Different sensitivities were observed for samples annealed in N-2, O-2, and as-grown conditions, providing valuable insights for practical applications.
Article
Chemistry, Analytical
Dong-Hyeon Kim, Michael A. Schweitz, Sang-Mo Koo
Summary: Annealing Ni/AlN/SiC heterojunction devices in an atmosphere of nitrogen and oxygen significantly improves the electrical properties of the structures, increasing the on/off ratio and decreasing the ideality factor. X-ray photoelectron spectroscopy provides direct indication of the bonding structure of the AlN layer.
Article
Materials Science, Multidisciplinary
Dong-Wook Byun, Young-Jae Lee, Jong-Min Oh, Michael A. Schweitz, Sang-Mo Koo
Summary: Beta-Ga2O3/4H-SiC heterojunction diodes were fabricated by depositing beta-Ga2O3 thin films on 4H-SiC substrates using radio frequency sputtering. X-ray diffraction analysis revealed increased reflectivity of crystal planes with optimized sputtering power. The improvement in carrier concentration and mobility was attributed to reduction of grain boundary scattering, leading to enhanced electrical characteristics in the heterojunction diode.
ELECTRONIC MATERIALS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Min-Yeong Kim, Hee-Jae Lee, Dong-Wook Byun, Seung-Woo Jung, Myeong-Cheol Shin, Michael A. Schweitz, Sang-Mo Koo
Summary: This study analyzes the effects of annealing on the electrothermal properties of Gallium Oxide (Ga2O3) thin films. The results show that the annealed sample has high current performance with a slight temperature rise.
Article
Materials Science, Multidisciplinary
Soo-Young Moon, Seung-Woo Jung, Hee-Jae Lee, Dong-Wook Byun, Myeong-Cheol Shin, Michael A. Schweitz, Sang-Mo Koo
Summary: The surface morphology and crystallinity of aluminum gallium oxide films were investigated, and it was found that the atmosphere during annealing affected the film properties.
Article
Materials Science, Multidisciplinary
Hyung-Jin Lee, Soo -Young Moon, Hee-Jae Lee, Dong-Wook Byun, Seung-Woo Jung, Michael A. Schweitz, Minkyung Kim, Jong -Min Oh, Weon Ho Shin, Chulhwan Park, Sang-Mo Koo
Summary: In this study, the influence of post-deposition annealing (PDA) on lithium phosphate (Li3PO4) thin films on silicon carbide (SiC) substrate was investigated in terms of materials and electrical properties. The results showed that the Li3PO4 films remained amorphous even after annealing at 400 degrees C. The highest ionic conductivity of 1.00 x 10-4 S/mm was achieved at 300 degrees C, and the rectification ratio of the annealed device was 1.45 x 103, 23 times higher than the as-deposited Li3PO4/SiC device without annealing. It suggests that precise control of Li3PO4 deposition can greatly enhance the performance of electronic devices and solid electrolyte batteries.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
