Article
Materials Science, Multidisciplinary
P. K. Shihabudeen, Ayan Roy Chaudhuri
Summary: The study found that the ethanol sensing performance of N-doped Indium oxide thin films is strongly dependent on their microstructure, with adsorption heat being a key factor influencing ethanol sensing response.
JOURNAL OF MATERIALS RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Liangge Xu, Jinye Yang, Kun Li, Lei Yang, Jiaqi Zhu
Summary: This study investigates the effect of post-deposition annealing process on the microstructure and optoelectronic properties of indium-hydroxide-doped thin films. The results show that the annealed films have high carrier mobility and transmittance, and exhibit excellent shielding performance against radar electromagnetic waves. This provides a guideline for fabricating lightweight, thin, and multi-functional shielding infrared transparent materials.
Article
Engineering, Electrical & Electronic
Pinar K. Bakacak, Emre Gur, Ozkan Bayram, Sebahattin Tuzemen, Onder Simsek
Summary: The study investigated the effects of growth pressure on the characteristics of ZrO2 thin films produced by radio frequency magnetron sputtering method. The results showed significant changes in structural and optical properties of the films, with XRD and PL analyses being particularly effective. ZrO2 thin films are considered promising materials for transparent electronic devices due to their high transmittance and ability to cover both visible and near-infrared spectral range.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Bowen Yan, Yanan Ding, Tongzheng Li, Haiyang Qiu, Yepeng Shi, Guoxia Liu, Fukai Shan
Summary: This article demonstrates a high-performance thin film transistor (TFT) based on a double-stack fluorine-doped In2O3/In2O3(InFO/InO) homojunction channel. By utilizing the unique bandgap characteristic of fluorine dopant, the TFT exhibits improved electrical performance, including a field-effect mobility (mu(FE)) of 5.69 cm(2)/Vs and a high ON/OFF current (I-on/I-off) ratio of 10(8). X-ray photoelectron spectroscopy (XPS) analysis confirms the significance of the InFO film as the front channel. Furthermore, integration with the Al2O3 dielectric enhances the TFT's electrical performance, resulting in a large mu(FE) of 31.49 cm(2)/Vs, high I-on/I-off (approximately 10(8)), and a small threshold voltage of 1.4 V. These findings highlight the great potential of the TFT based on InFO/InO homojunction channel in low-power, flexible, and printable electronic devices.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Optics
S. A. Alghamdi, A. A. A. Darwish, I. S. Yahia, E. F. M. El-Zaidia
Summary: The structure and optical properties of InClPc films deposited on FTO substrates by thermal vacuum evaporation technique were studied, revealing two energy gaps and nonlinear optical parameters. The optical limiting testing showed high performance of the red He-Ne laser.
Article
Chemistry, Multidisciplinary
Mengwei Si, Yaoqiao Hu, Zehao Lin, Xing Sun, Adam Charnas, Dongqi Zheng, Xiao Lyu, Haiyan Wang, Kyeongjae Cho, Peide D. Ye
Summary: This work demonstrates enhancement-mode field-effect transistors using an atomically-deposited amorphous In2O3 channel with thickness as low as 0.7 nm. The controllable thickness of In2O3 at an atomic scale allows for the design of sufficient 2D carrier density in the channel, affecting threshold voltage and channel carrier density. The model of trap neutral level (TNL) explains how the Fermi level aligns in the conduction band of In2O3 due to the quantum confinement effect, as confirmed by density function theory (DFT) calculations.
Article
Engineering, Electrical & Electronic
Durmus Ali Aldemir, Ahmet Bugrahan Bayram, Murat Kaleli
Summary: The In2O3, Yb2O3, and (In, Yb)(2)O-3 thin films were prepared using the ultrasonic spray pyrolysis method. The structural and electro-optical properties of (In, Yb)(2)O-3 thin films were compared with those of In2O3 and Yb2O3 thin films. It was found that (In, Yb)(2)O-3 had a cubic bixbyite crystal structure with a lattice constant of 1.030 nm. The (In, Yb)(2)O-3 material was identified as a direct ultra-wide bandgap semiconductor with a value of 4.11 eV.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Multidisciplinary
K. Erturk, M. Isik, M. Terlemezoglu, N. M. Gasanly
Summary: In this study, the structural and optical characteristics of Cd1-xZnxS (CdZnS) thin films grown by electrodeposition were investigated. The films exhibited a cubic wurtzite structure, with Zn doping concentration found to be 5%. Raman spectra showed a blue-shift for CdZnS, and temperature-dependent band gap energy decreased from 2.56 eV at 10 K to 2.51 eV at 300 K. The Varshni optical model was applied to study the dependency of band gap energy on temperature, and various optical parameters were reported based on the model results.
Article
Engineering, Electrical & Electronic
D. Berman-Mendoza, O. Diaz-Grijalva, R. Lopez-Delgado, A. Ramos-Carrazco, M. E. Alvarez-Ramos, F. Romo-Garcia, H. J. Higuera-Valenzuela, R. Rangel
Summary: The growth of CdS thin films by chemical bath deposition and doping with copper ions was reported to produce pseudo-MOSFETs with adjustable channel currents. Cu-doping was found to improve the electrical behavior of the thin film transistors, leading to changes from n-type to p-type channels with different mobilities. This study contributes to the development of thin film transistors by introducing Cu ions to modify their electrical properties.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Bibi Zulaika Bhari, Kazi Sajedur Rahman, Puvaneswaran Chelvanathan, Mohd Adib Ibrahim
Summary: Magnesium-doped Zinc Oxide (MZO) thin films were grown by RF magnetron sputtering and subsequently annealed to modify the structure and optical properties. XRD analysis showed a peak shift and FESEM revealed an increase in grain size. The optical characterization demonstrated enhanced transmission and tunable energy band gap.
Article
Materials Science, Ceramics
Sema Kurtaran, Gokhan Kilic, Shams A. M. Issa, H. O. Tekin
Summary: A group of novel CeO2 thin films were synthesized using ultrasonic spray pyrolysis process. The composition ratios of these films were modified to investigate changes in their optical, surface, electrical, and structural characteristics. The films exhibited promising properties for optoelectronic and nuclear security applications, with high resistivity and potential for nuclear radiation shielding.
CERAMICS INTERNATIONAL
(2022)
Review
Nanoscience & Nanotechnology
Zhandong Li, Dmitry Kurouski
Summary: The review critically discusses recent progress in understanding hot carrier-driven chemistry and catalytic processes at the nanoscale. Experimental and theoretical findings are presented to demonstrate novel plasmon-driven reactivity for redox, coupling, elimination, and scissoring reactions. Additionally, the impact of these findings on plasmonic catalysis and TERS imaging is discussed in the review.
Article
Materials Science, Ceramics
Housei Akazawa
Summary: Both undoped and Er3+-doped Bi2O3 thin films were sputter-deposited on Si(100) substrates, exhibiting varying refractive indices and emission characteristics. Er3+ emissions peaking at 532 nm were observed in the Er3+-doped Bi2O3 films, with concentration quenching potentially influenced by the deposition temperature.
CERAMICS INTERNATIONAL
(2021)
Article
Physics, Condensed Matter
Jing Yang, Jiangtao Xu, Dagang Miao, Shouxiang Jiang
Summary: In this study, CZTS thin films were fabricated using different argon flow rates to control compositional variations, with films sputtered at 300 sccm showing the lowest copper content, high zinc richness, high crystallization level, and minimal voids, with a band gap energy of approximately 1.5 eV. These results suggest that controlling the composition of sputtered CZTS thin films through argon flow rate significantly impacts the properties of sulfurized CZTS thin films.
PHYSICA B-CONDENSED MATTER
(2021)
Article
Optics
A. Q. Alosabi, A. A. Al-Muntaser, M. M. El-Nahass, A. H. Oraby
Summary: The structural and optical properties of disodium phthalocyanine (Na2Pc) thin films prepared using the thermal evaporation method were investigated theoretically and experimentally. The optimized geometry, vibrational bands, and energy gap of the films were predicted by density functional theory (DFT) computations. Structural analysis using FTIR and XRD techniques showed that the thin films had an amorphous structure. UV-Vis-NIR spectrophotometry revealed that the Na2Pc molecules exhibited four absorption bands in the UV-Vis region, and the energy transitions were determined to be indirect allowed. The absorption coefficient and energy gap indicated the potential applications of the Na2Pc thin films in optoelectronic devices. The film thickness did not affect the absorption index and refractive index, which were determined to be independent. The dispersion parameters were evaluated using a single oscillator model in the non-absorbing region.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Adeel Liaqat, Yiheng Yin, Sabir Hussain, Wen Wen, Juanxia Wu, Yuzheng Guo, Chunhe Dang, Ching-Hwa Ho, Zheng Liu, Peng Yu, Zhihai Cheng, Liming Xie
Summary: As the size of metal oxide semiconductor field-effect transistors (FETs) is scaled down, power dissipation becomes a major challenge. The use of negative capacitance (NC) effect enables a new path to achieve a low sub-threshold swing (SS) below the Boltzmann limit. In this work, a NC-FET from an all two-dimensional (2D) metal ferroelectric semiconductor (MFS) vertical heterostructure has been demonstrated, showing steep slopes switching over a wide range of source-drain current.
Article
Nanoscience & Nanotechnology
Cheng-Chieh Lin, Kai-Di Yang, Min-Chuan Shih, Shao-Ku Huang, Tzu-Pei Chen, Hung-Chang Hsu, Ching-An Chuang, Chih-Ying Huang, Lucas Wang, Chia-Chun Chen, Ching-Hwa Ho, Ya-Ping Chiu, Chun-Wei Chen
Summary: This study demonstrates the presence of internal built-in electric fields (BIEFs) in 2D organic-inorganic hybrid Ruddlesden-Popper perovskites (OIRPPs). The strength of these BIEFs reduces with increased quantum well width. The origin of these BIEFs is attributed to molecular dipoles pointing to the organic-inorganic interfaces. This discovery provides deep insight into understanding the optical properties of 2D OIRPPs for the future design of large-area and low-cost perovskite optoelectronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Adzilah Shahna Rosyadi, Alvin Hsien-Yi Chan, Jia-Xin Li, Chang-Hua Liu, Ching-Hwa Ho
Summary: This study focuses on impurity doping experiments in 2D transition-metal dichalcogenides (TMD). Different carrier types were observed under different chromium doping concentrations. Structural and optical characterization revealed that the crystal structure and bandgap of chromium-doped ReSe2 remained unchanged.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Tian-Yun Chang, Po-Liang Chen, Pei-Sin Chen, Wei-Qing Li, Jia-Xin Li, Ming-Yuan He, Jen-Te Chao, Ching-Hwa Ho, Chang-Hua Liu
Summary: This study demonstrates the potential of using band-engineered van der Waals hetero-structures as bias-selectable photodetectors. By tuning the bias polarity, the spectral photoresponse can be switched between different bands, showing high external quantum efficiency and fast operation speed.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Applied
Wei Li, Jeng-Yu Ke, Yun-Xuan Ou-Yang, Ying-Xuan Lin, Ching-Hwa Ho, Kuei-Yi Lee, Shunjiro Fujii, Shin-ichi Honda, Hideaki Okado, Masamichi Naitoh
Summary: In this study, MoS2 bulk was synthesized using the chemical vapor transport method, and the thickness of MoS2 flakes was limited through mechanical exfoliation. The MoS2 characteristics were transformed from n-type to p-type using oxygen plasma treatment to fabricate a p-n homogeneous junction, and the charge neutrality point shift was successfully demonstrated using FET measurement. The MoS2 p-n homogeneous junction diode showed excellent p-n characteristic curve and performed great rectifying behavior in the half-wave rectification experiment.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Ewa Zuberek, Martyna Majak, Jakub Lubczynski, Joerg Debus, Kenji Watanabe, Takashi Taniguchi, Ching-Hwa Ho, Leszek Bryja, Joanna Jadczak
Summary: Monolayers of transition-metal dichalcogenides with direct band gap located at specific points in the Brillouin zone show promising applications in opto- and spin-electronics due to enhanced Coulomb interactions and specific spin-valley properties. Processes demonstrating the upconversion of light into bright intravalley excitons in WS2 monolayers provide insight into various interactions, including resonant optical phonons, cooling of resident electrons, and non-local electron-hole exchange. Temperature-dependent studies on excitonic upconversion intensity suggest increased phonon population and thermally enhanced electron scattering in two-dimensional quantum materials, shedding new light on excitonic properties and photonic upconversion mechanisms in van der Waals heterostructures.
SCIENTIFIC REPORTS
(2022)
Article
Nanoscience & Nanotechnology
Luthviyah Choirotul Muhimmah, Yu-Hong Peng, Feng-Han Yu, Ching-Hwa Ho
Summary: This study investigated the structural and optical properties of full-series multilayer GaTe1-xSex (0 ≤ x ≤ 1). Experimental results showed that the GaTe1-xSex layers may contain hexagonal (H) phase and monoclinic (M) phase, with the H-phase dominating when x ≥ 0.5. The photon emission energy of the M-phase GaTe1-xSex increased as the Se content increased, while that of the H-phase GaTe1-xSex decreased in the red to near-infrared (NIR) region. The decay lifetime of the band-edge emission was faster in the M phase than in the H phase for 0 ≤ x ≤ 0.4. The predominantly H phase GaTe1-xSex showed greater dark resistivity and photoconductive response under visible-light illumination. The GaTe1-xSex multilayers demonstrated superior light-emission and photodetection capability for future optoelectronic devices.
NPJ 2D MATERIALS AND APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Po-Liang Chen, Tian-Yun Chang, Pei-Sin Chen, Alvin Hsien-Yi Chan, Adzilah Shahna Rosyadi, Yen-Ju Lin, Pei-Yu Huang, Jia-Xin Li, Wei-Qing Li, Chia-Jui Hsu, Neil Na, Yao-Chang Lee, Ching-Hwa Ho, Chang-Hua Liu
Summary: This study presents a two-terminal mid-infrared (mid-IR) emitter that allows control of spectral characteristics and polarization states by tuning the polarity of the applied bias. The emitter consists of back-to-back p-n junctions formed by stacking anisotropic light-emitting materials (black phosphorus and black arsenic-phosphorus with MoS2). The emissions of the two junctions exhibit distinct spectral ranges and polarization directions, and can be independently activated depending on the polarity of the applied bias.
Article
Chemistry, Physical
Joanna Jadczak, Janusz Andrzejewski, Joerg Debus, Ching-Hwa Ho, Leszek Bryja
Summary: Germanium monosulfide with an anisotropic puckered crystalline structure has unique optical and electronic properties, but the understanding of exciton-phonon interactions is limited. In this study, we investigate the resonant Raman scattering and photoluminescence of the optically active Gamma-exciton in layered GeS flakes, revealing the coupling between phonons and photogenerated carriers as well as the efficiency of multiorder scattering in optical processes.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Thalita Maysha Herninda, Chin En Hsu, Hung-Chung Hsueh, Ching-Hwa Ho
Summary: Two-dimensional semiconductors based on black phosphorus (BP) structure have attracted significant attention recently due to their strong in-plane anisotropy and potential applications in polarized optoelectronic devices, axial-dependent carrier transport, and asymmetric 2D electronic and energy devices. In this study, multilayered SnS1-xSex chalcogenides were grown by chemical vapor transport and exfoliated on a SiO2/Si substrate for optical characterization. The results showed strong in-plane anisotropy, with the maximum Raman intensity of the AM chain vibration mode (Ag) being mutually orthogonal to the ZZ chain-oriented mode (B1g) in the full-series multilayer SnS1-xSex compounds. A physical mechanism of symmetry breaking was proposed to explain the increased number of separated Ag and B1g modes with different energies for intermediate compositions compared to binary compounds of SnS and SnSe. Additionally, the bandgap value of the ZZ polarized direction was found to be lower than that of the AM direction for each of the SnS1-xSex compounds.
MATERIALS TODAY ADVANCES
(2023)
Article
Chemistry, Physical
Joanna Jadczak, Joerg Debus, Justyna Olejnik, Ching-Hwa Ho, Kenji Watanabe, Takashi Taniguchi, Leszek Bryja
Summary: This study investigates the upconversion of exciton photoluminescence in MoSe2 monolayers. The resonant interaction between high-order exciton complexes and K-valley phonons leads to enhanced emission in the trion and biexciton transitions.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Ching-An Chuang, Feng-Han Yu, Bo-Xian Yeh, Anna Milatul Ummah, Adzilah Shahna Rosyadi, Ching-Hwa Ho
Summary: Near-band-edge emissions from red to blue colors have been detected in full-series GaSe1-xSx multilayers. The crucial phase responsible for direct recombination and emission of free excitons within the visible range is identified as the & epsilon;-stacked phase. The multilayer GaSe1-xSx represents a well-suited 2D chalcogenide series for emitting full-color visible light.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Meng-Yu Tsai, Chia-Tse Huang, Che-Yi Lin, Mu-Pai Lee, Feng-Shou Yang, Mengjiao Li, Yuan-Ming Chang, Kenji Watanabe, Takashi Taniguchi, Ching-Hwa Ho, Wen-Wei Wu, Mahito Yamamoto, Jiunn-Lin Wu, Po-Wen Chiu, Yen-Fu Lin
Summary: A reconfigurable field-effect transistor based on a hexagonal boron nitride/rhenium diselenide/hexagonal boron nitride heterostructure offers nonvolatile control of polarity through photoinduced trapping mechanism and can emulate synaptic functions.
NATURE ELECTRONICS
(2023)
Article
Chemistry, Physical
Anna Milatul Ummah, Yu-Hung Peng, Ching-Hwa Ho
Summary: This work investigates the structural, optical, and vibrational behaviors of MnPS3 and discovers the N'eel ordering transformation through temperature-dependent structure and optical measurements. It is found that MnPS3 exhibits high magnon-phonon coupling in the antiferromagnetic state, which is influenced by the ordered spin in the 3d orbital of the Mn2+ cation. The study also detects band-edge excitons of thin-layered MnPS3 through micro-thermoreflectance measurements, revealing a magnetic transition from antiferromagnetic to paramagnetic ordering below the Neel temperature.
Letter
Chemistry, Physical
Joanna Jadczak, Janusz Andrzejewski, Joerg Debus, Ching-Hwa Ho, Leszek Bryja
Summary: Germanium monosulfide with a puckered crystalline structure has unique optical and electronic properties, which have attracted much attention. However, the interactions between excitons and phonons have not been fully understood. In this study, we investigated the resonant Raman scattering and photo-luminescence of the optically active Gamma-exciton in layered GeS flakes. We found that there is a considerable coupling between phonons and photogenerated carriers in GeS flakes, and multiorder scattering plays an important role in optical processes.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)