Article
Materials Science, Multidisciplinary
Vittorio Bonino, Ngelo Angelini
Summary: We investigated the optical behavior of a nanostructured diamond surface on a glass substrate. Our numerical model shows that a simple geometrical pattern can sustain Fano-like resonances with a high Q-factor of up to 3.5×10^5 when excited by normally incident plane waves. We found that the geometrical parameters of the nanopillars affect both the resonant frequency and line shape. This nanostructured surface can be directly used as a refractive index sensor with high sensitivity and linearity. Our findings demonstrate that diamond-based meta-surfaces provide a valuable platform for nanophotonics, allowing control of light propagation at the nanoscale and enabling significant field enhancement within the nanoresonators, leading to both linear and nonlinear effects.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Physics, Applied
Yuncong Cai, Zhaoqing Feng, Zhengxing Wang, Xiufeng Song, Zhuangzhuang Hu, Xusheng Tian, Chunfu Zhang, Zhihong Liu, Qian Feng, Hong Zhou, Jincheng Zhang, Yue Hao
Summary: By introducing a hybrid floating gate structure, we demonstrated the enhancement of E-mode Ga2O3 MOSFET in multiple performance metrics, providing a promising path for the development of enhancement-mode Ga2O3 power devices.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Haodong Fan, Xiaoju Wang, Linhong Zha, Kangcheng Qi, Zengjie Gu
Summary: In this study, a LaB6 nanofilm is coated on the top surface of silicon nanopillars, creating a structure called a LaB6 hat-coated Si-FEA. The electron emission mechanism of this structure is analyzed using OPERA simulation software, which reveals the importance of LaB6 film edge in electron emission. Experimental results of a LaB6 hat-coated Si-FEA sample prepared using microsphere lithography show good agreement with the simulation results, indicating the potential for low-cost, highly integrated, and high-current field emission cathodes by utilizing LaB6 as an emitter material with microsphere lithography technology.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Chemistry, Physical
Yongjian Li, Xinlu Li, Li Luo, Yuchen Meng, Zhen Qin, Jialong He, Ronghua Wang
Summary: In this work, vertical graphene was grown in controllable patterns through macro-geometric modulation of nickel substrates, leading to a decrease in the turn-on electric field and reduced current variation. The outstanding field emission properties of patterned vertical graphene (PVG) were attributed to the weakening of field shielding and stronger contribution from VG grown on Ni aggregation. SEM and TEM observations confirmed the structural stability of VG and its connection to the substrate. The results provide insights into the influence of structural stability on field emission properties.
SURFACES AND INTERFACES
(2023)
Article
Optics
Zhichao Zhu, Bo Liu, Huili Tang, Chuanwei Cheng, Mu Gu, Jun Xu, Chi Zhang, Xiaoping Ouyang
Summary: By using hollow nanosphere arrays with high-index contrast, the light extraction efficiency of beta-Ga2O3 crystals has been enhanced in this study. The control of the refractive index and thickness of the shell of the hollow nanospheres can significantly increase the light extraction efficiency, as shown by both numerical simulations and experiments.
Article
Chemistry, Multidisciplinary
Connor J. McClellan, Eilam Yalon, Kirby K. H. Smithe, Saurabh Suryavanshi, Eric Pop
Summary: This study demonstrates a method of low-temperature substoichiometric AlOx doping for monolayer MoS2, achieving high carrier densities and low sheet resistance in transistors. The doped MoS2 devices approach several low-power transistor metrics required by the international technology roadmap, making them promising for future semiconductor applications.
Article
Nanoscience & Nanotechnology
Aniello Pelella, Alessandro Grillo, Francesca Urban, Filippo Giubileo, Maurizio Passacantando, Erik Pollmann, Stephan Sleziona, Marika Schleberger, Antonio Di Bartolomeo
Summary: Monolayer molybdenum disulfide nanosheets obtained via chemical vapor deposition were used to fabricate field-effect transistors with n-type conduction, high on/off ratio, and good mobility. The study demonstrated that the voltage applied to the Si substrate back-gate can modulate the field emission current.
ADVANCED ELECTRONIC MATERIALS
(2021)
Article
Physics, Applied
Peng Zhang, Yee Sin Ang, Allen L. Garner, Agust Valfells, J. W. Luginsland, L. K. Ang
Summary: This Perspective reviews the fundamental physics of space-charge interactions and recent developments in the space-charge limited current model. It focuses on theoretical aspects such as nano-scale physics, time-dependent behaviors, higher-dimensional models, and transitions between electron emission mechanisms. Future directions in theoretical modeling and applications of SCLC are highlighted.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Optics
I. I. Musiienko, S. O. Lebedynskyi, R. Kholodov
Summary: This article introduces a potential barrier model considering an additional current and shows the oscillatory resonance feature of field emission current from a double-layer metal system with a nanoscale coating, revealing resonant properties of the current. It also observes that the field emission current increases significantly when not ideal copper surface with nanoclusters or nanoscale voids are present on the surface.
EUROPEAN PHYSICAL JOURNAL D
(2022)
Article
Chemistry, Analytical
Shuzhen Dou, Jiaxin Lu, Qiye Chen, Chunning Chen, Nan Lu
Summary: The abuse of antibiotics in recent years has had adverse effects on water environment and food safety. Monitoring the antibiotic content in water and food is crucial for environmental protection and human health. In this study, a chip composed of high-density Si nanopillars and Ag nanoislands was developed for sensitive detection of sulfonamides using SALDI-MS. The chip demonstrated high detection sensitivity and rapid quantification, making it a promising tool for food and environmental monitoring.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Materials Science, Multidisciplinary
Haidong Yuan, Jie Su, Pengliang Zhang, Zhenhua Lin, Jincheng Zhang, Jie Zhang, Jingjing Chang, Yue Hao
Summary: The optoelectronic properties of beta-Ga2O3/Janus-TMD heterostructures were investigated with different E(in)s, revealing the impact of E-in direction on band alignments and providing guidance for designing high-performance Ga2O3 optoelectronic devices.
MATERIALS TODAY PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Penghui Li, Linpeng Dong, Chong Li, Bin Lu, Chen Yang, Bo Peng, Wei Wang, Yuanhao Miao, Weiguo Liu
Summary: In this study, the influence of indium doping on the exfoliation efficiency, stability, and structural and electronic properties of ML Ga2O3 is systematically investigated. The results show that indium doping can reduce the exfoliation energy of ML Ga2O3 to a similar level as typical van der Waals 2D materials and maintain excellent stability even at high doping concentrations. Additionally, indium doping can modify the bandgap of ML Ga2O3, improve the electron mobility, and significantly decrease the hole mobility. The simulation of MOSFETs based on indium-doped ML Ga2O3 demonstrates enhanced device performance and potential for sub-5 nm applications.
Article
Optics
Jingshu Guo, Chaoyue Liu, Laiwen Yu, Hengtai Xiang, Yuluan Xiang, Daoxin Dai
Summary: Graphene-silicon-graphene waveguide photodetectors operating at wavelengths of 1.55 and 2 μm are demonstrated with potential for large-scale integration. The photodetectors exhibit high bandwidth, ultra-low dark current, high photo-to-dark current ratio, and high linear dynamic range.
LASER & PHOTONICS REVIEWS
(2023)
Article
Chemistry, Physical
Xingqi Ji, Xuemei Yin, Yuzhuo Yuan, Shiqi Yan, Xiaoqian Li, Zijian Ding, Xinyu Zhou, Jiawei Zhang, Qian Xin, Aimin Song
Summary: In this study, Schottky photodiodes with sputtered amorphous Ga2O3 were fabricated for the first time and achieved excellent solar-blind detection performances. The high performance can be attributed to the large concentration of oxygen vacancies, the possible photo released carriers from deep-level acceptors, and the high film uniformity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Shao-Yu Chu, Mu-Ju Wu, Tsung-Han Yeh, Ching-Ting Lee, Hsin-Ying Lee
Summary: In this study, GaOOH nanorods were grown using the hydrothermal synthesis method and then converted to Ga2O3 nanorods, which were used as the sensing membranes of NO2 gas sensors. The optimal surface-to-volume ratio of the GaOOH nanorods was achieved by controlling the thickness of the seed layer and the concentrations of the hydrothermal precursor. By annealing the GaOOH nanorods at different temperatures, Ga2O3 nanorods were obtained. The gas sensors using the Ga2O3 nanorod sensing membrane annealed at 400°C showed the best performance.
Article
Physics, Applied
Ta-Shun Chou, Palvan Seyidov, Saud Bin Anooz, Raimund Grueneberg, Jana Rehm, Tran Thi Thuy Vi, Andreas Fiedler, Kornelius Tetzner, Zbigniew Galazka, Martin Albrecht, Andreas Popp
Summary: In this study, the development of unwanted parasitic particles in the MOVPE chamber during the growth of mu m level films is comprehensively investigated. The density of parasitic particles is observed to be significant at film thicknesses starting from >1.5 to 2 mu m. These particles induce structural defects, such as twin lamellae, which adversely affect the electrical properties of the grown film. The parasitic particles originate from parasitic reactions within the chamber triggered by the promoted gas-phase reactions during the growth process, and their density can be reduced by increasing total gas flow and reducing the showerhead distance to the susceptor. After minimizing the density of parasitic particles, film thicknesses up to 4 mu m have been achieved. RT Hall measurements reveal carrier mobilities of 160 cm(2)V(-1)s(-1) at carrier concentrations of 5.7 x 10(16) cm(-3).
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Zbigniew Galazka, Andreas Fiedler, Andreas Popp, Steffen Ganschow, Albert Kwasniewski, Palvan Seyidov, Mike Pietsch, Andrea Dittmar, Saud Bin Anooz, Klaus Irmscher, Manuela Suendermann, Detlef Klimm, Ta-Shun Chou, Jana Rehm, Thomas Schroeder, Matthias Bickermann
Summary: We studied the growth and physical properties of β-(AlxGa1-x)(2)O-3 single crystals with different Al contents using the Czochralski method. The Al segregation coefficient in the Ga2O3 melt resulted in higher Al content in the crystals. By co-doping with Si or Mg, we obtained semiconducting, degenerately semiconducting, or semi-insulating crystals. The lattice constants decreased anisotropically, while the optical bandgap increased linearly with Al content.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Crystallography
Ta-Shun Chou, Saud Bin Anooz, Raimund Grueneberg, Thuy Vi Thi Tran, Jana Rehm, Zbigniew Galazka, Andreas Popp
Summary: Si-doped beta-Ga2O3 layers were grown on (100) beta-Ga2O3 semi-insulating substrates by MOVPE, and their reflection spectrum on the substrate surface was investigated. Transforming the reflectance spectrum into the autocorrelation domain revealed a more pronounced Fabry-Pe 'rot oscillation, which allowed for easy estimation of the growth rate and growth mode based on the period and damping behavior of the spectrum. The observed oscillation contributed to the refractive index difference between the substrate and the film caused by impurities and preparation techniques. The high sensitivity of reflectance spectroscopy demonstrated its advantage as a powerful growth process monitoring tool.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Chemistry, Multidisciplinary
Somayeh Tajik, Fatemeh Sharifi, Behnaz Aflatoonian, Antonio Di Bartolomeo
Summary: This article introduces an ultrasensitive and selective voltammetric sensor for the determination of ketoconazole (KTC) in real samples. It utilizes a modified carbon paste electrode with a sheaf-like Ce-BTC MOF nanostructure and ionic liquid. The electrode exhibits excellent electrocatalytic activity for KTC oxidation, with a detection limit of 0.04 μM and a sensitivity of 0.1342 μA·μM-1. It can effectively monitor KTC in aqueous samples.
Article
Nanoscience & Nanotechnology
Aniello Pelella, Daniele Capista, Maurizio Passacantando, Enver Faella, Alessandro Grillo, Filippo Giubileo, Nadia Martucciello, Antonio Di Bartolomeo
Summary: In this study, a photodetector with bias-tuneable current is achieved by adding a CNT/Si3N4/Si capacitor to a prefabricated metal-insulator-semiconductor diode. The device exhibits high photoresponsivity and external quantum efficiency, and can be used as an optoelectronic Boolean logic device. It also possesses the capability of self-powering.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Mohammad Bagher Askari, Hadi Beitollahi, Antonio Di Bartolomeo
Summary: Recently, the synthesis of a three-component catalyst consisting of zirconium oxide (ZrO2), nickel oxide (NiO), and reduced graphene oxide (rGO) in the form of ZrO2/NiO/rGO has been achieved by a simple one-step hydrothermal method. The catalyst exhibited excellent methanol and ethanol electrooxidation abilities with high current densities and cyclic stabilities, making it an attractive option for anode materials in alcoholic fuel cells. The detailed characterization and electrochemical tests demonstrate the outstanding capability of this new nanocatalyst.
Article
Chemistry, Multidisciplinary
Daniele Capista, Luca Lozzi, Aniello Pelella, Antonio Di Bartolomeo, Filippo Giubileo, Maurizio Passacantando
Summary: Photodetectors based on vertical multi-walled carbon nanotube (MWCNT) film-Si heterojunctions are successfully achieved by growing MWCNTs on n-type Si substrates covered with Si3N4 layers. Spatially resolved photocurrent measurements demonstrate that higher photo detection is achieved in regions with thinner MWCNT film, resulting in nearly 100% external quantum efficiency. Therefore, a simple method utilizing scotch tape is proposed to tune the thickness and density of the as-grown MWCNT film, thereby enhancing the device photo-response.
Article
Nanoscience & Nanotechnology
Kimberly Intonti, Enver Faella, Loredana Viscardi, Arun Kumar, Ofelia Durante, Filippo Giubileo, Maurizio Passacantando, Hoi Tung Lam, Konstantinos Anastasiou, Monica F. Craciun, Saverio Russo, Antonio Di Bartolomeo
Summary: This study reports the optoelectronic characterization of few-layer ReSe2 field effect transistors at different pressures. The devices exhibit a dominant n-type behavior with low Schottky barrier and significant hysteresis. The conductance and mobility of the devices are affected by air pressure, increasing with lower pressure due to the desorption of electronegative air molecules. The photoresponse of the device changes from positive photoconductivity at higher pressure to negative photoconductivity at lower pressure, which can be explained by the desorption of molecules and the defect trapping of photogenerated carriers.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Arun Kumar, Loredana Viscardi, Enver Faella, Filippo Giubileo, Kimberly Intonti, Aniello Pelella, Stephan Sleziona, Osamah Kharsah, Marika Schleberger, Antonio Di Bartolomeo
Summary: We investigated the temperature dependence of transport properties and memory behavior in ultrathin black phosphorus field-effect transistors. The devices displayed a decrease in electrical conductance and field-effect mobility as the temperature increased. The field-effect mobility was 283 cm(2)V(-1)s(-1) at 150 K and reduced to 33 cm(2)V(-1)s(-1) at 340 K when the voltage gate sweep range was +/- 50 V. The transfer characteristics exhibited an increasing hysteresis width with temperature, which was utilized to create non-volatile memories with a wider programming window at higher temperatures.
Article
Nanoscience & Nanotechnology
Kimberly Intonti, Enver Faella, Arun Kumar, Loredana Viscardi, Filippo Giubileo, Nadia Martucciello, Hoi Tung Lam, Konstantinos Anastasiou, Monica Craciun, Saverio Russo, Antonio Di Bartolomeo
Summary: The electrical behavior and photoresponse of rhenium disulfide field-effect transistors (FETs) with Cr-Au contacts were investigated, and their temperature-dependent characteristics were studied. The photocurrent was found to increase with temperature and showed a linear dependence on the incident light power at low and room temperatures, with longer rise/decay time at higher temperatures.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Arun Kumar, Enver Faella, Ofelia Durante, Filippo Giubileo, Aniello Pelella, Loredana Viscardi, Kimberly Intonti, Stephan Sleziona, Marika Schleberger, Antonio Di Bartolomeo
Summary: In this study, a simple approach for a nonvolatile opto-electronic memory device based on a MoS2 transistor with light induced charge storage capability is presented. The device exhibits a high on/off current ratio and hysteresis width modulation by air pressure, and shows persistent photoconductivity with excellent photo responsive memory performance. Furthermore, the combination of gate voltage and light can be used to control the transistor current and increase the memory window significantly.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Nanoscience & Nanotechnology
A. Di Bartolomeo, A. Kumar, O. Durante, A. Sessa, E. Faella, L. Viscardi, K. Intonti, F. Giubileo, N. Martucciello, P. Romano, S. Sleziona, M. Schleberger
Summary: The photoconductivity of monolayer MoS2 back-gate transistors is investigated with respect to temperature and pressure. The photocurrent shows linear increase with light intensity, reaching a maximum responsivity of approximately 30 A/W in air. The photocurrent enhancement is observed at elevated temperatures and reduced pressures, which can be attributed to the desorption of adsorbates such as O2 and H2O molecules, leading to an increase in the n-doping level and channel current.
MATERIALS TODAY NANO
(2023)
Article
Chemistry, Multidisciplinary
Stephan Sleziona, Aniello Pelella, Enver Faella, Osamah Kharsah, Lucia Skopinski, Andre Maas, Yossarian Liebsch, Jennifer Schmeink, Antonio Di Bartolomeo, Marika Schleberger
Summary: Field-effect transistors based on molybdenum disulfide (MoS2) were irradiated with Xe30+ ions to introduce defects and investigate their effects on electrical properties. The irradiation resulted in decreased charge carrier mobility and increased conductivity, as well as a significantly reduced n-doping and enhanced hysteresis. The irradiated MoS2 transistor exhibited memory-like behavior with remarkably longer relaxation times compared to previous works.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Aniello Pelella, Kimberly Intonti, Loredana Viscardi, Ofelia Durante, Daniele Capista, Maurizio Passacantando, Filippo Giubileo, Paola Romano, Mohammed Ali S. Alshehri, Manal Safar G. Alghamdi, Monica Felicia Craciun, Saverio Russo, Antonio Di Bartolomeo
Summary: Mechanically exfoliated two-dimensional alpha-In2Se3 flakes are used as channel material in field effect transistors, showing good conductivity and visible light response.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
