Article
Engineering, Chemical
Caifeng Chen, Ruifang Zhang, Jiaguang Zhu, Xinyi Qian, Jing Zhu, Xuan Ye, Muyu Zhang
Summary: PVDF/ZnO thin films were prepared using a direct writing method, with the addition of nano-ZnO significantly improving the crystallinity and beta phase content of the PVDF film. Additionally, the dielectric constant of the composite film was greatly increased and the conductivity improved through the combined action of adding ZnO nanoparticles and electric field assistance.
POLYMER ENGINEERING AND SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
Z. Cicek, S. Yakut, D. Deger, D. Bozoglu, S. Mustafaeva, P. Ismailova, A. A. Hasanov, K. Ulutas
Summary: Bulk TlGaS2 single crystals were produced by the Bridgman method, while TlGaS2 thin film samples were deposited from bulk crystals using the thermal evaporation technique. Three polarization mechanisms were detected from the analysis of Cole-Cole plots, with different behaviors at different frequencies. The dielectric constant of the thin films was found to be 100-1000 times higher than that of the bulk single crystal at frequencies below 100 Hz.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Chemistry, Physical
B. Amudhavalli, R. Mariappan, M. Prasath
Summary: This review discusses the applications of thin film materials in various fields and explores the advantages and disadvantages of different chemical deposition methods. The influence of preparative parameters on the properties of thin films is also discussed.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Instruments & Instrumentation
S. Bozoian, L. Kalaydjian, J. Younes, M. Tabbal, M. Kazan
Summary: Infrared reflectivity measurements were conducted on c-axis oriented zinc oxide thin films deposited on glass to investigate the effect of deposition temperature and film thickness on their physical properties. The results show that film thickness significantly affects the ratio of high-frequency dielectric constants parallel and perpendicular to the c-axis, while the damping factor decreases with increasing film thickness. Additionally, the zinc oxide films deposited on glass exhibit a significant density of free carriers with high mobility. Therefore, the infrared dielectric and plasmonic properties of the zinc oxide films can be tuned by adjusting the deposition temperature and film thickness to meet the requirements of various technological applications.
INFRARED PHYSICS & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Seval Aksoy Pehlivanoglu, Ozgur Polat
Summary: ZnO and Ir-doped ZnO thin films were fabricated by sol-gel spin coating technique. The structures and properties of the films were investigated. The addition of Ir increased the volume of the unit cell, atomic packing fraction, and grain size of the thin films. Optical bandgap decreased with Ir substitution. The transmittance and optical dielectric properties were also affected by Ir doping.
Article
Materials Science, Multidisciplinary
Haiyang Xu, Xingwei Ding, Jie Qi, Xuyong Yang, Jianhua Zhang
Summary: By depositing a thin Al2O3 film on the surface of a Y2O3 dielectric layer using atomic layer deposition technology, the electrical performance and bias stability of ZnO TFT devices were greatly improved.
Article
Chemistry, Physical
ChenLin Wang, MinJu Ying, Jie Lian, MingYang Wei, QingFen Jiang, Qian Li, Yu Zhang, Zhen Xu, YueMing Wang
Summary: In this study, O-polar ZnO films were prepared using molecular beam epitaxy and ion implantation was used to introduce Co ions and Sm ions into the films. Various characterization techniques were employed to study the structure, optical, and dielectric properties of the samples. The results showed changes in surface roughness and dielectric properties after ion implantation, indicating potential for application in optoelectronic devices.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Electrical & Electronic
Hadjer Hakkoum, Abderrahim Moumen, Mebrouk Ghougali, Nouredine Sengouga, Elisabetta Comini
Summary: Material properties are crucial for the efficiency and performance of optoelectronic devices like photodetectors, and we focused on fabricating a NiO/ZnO heterojunction with improved structural properties. By varying the spray solution volume, we investigated the influence of NiO and ZnO thickness on the structural and morphological properties using spray pyrolysis. Thicker NiO and ZnO films were found to be optimal for fabricating the desired heterostructure. Raman and XRD results confirmed the formation of the NiO/ZnO heterostructure, which exhibited smooth morphology without any pinholes. Further simulations allowed for studying the impact of structural properties on the photodetector performance.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Materials Science, Multidisciplinary
S. S. Fouad, L. I. Soliman, E. Baradacs, M. E. Sayed, B. Parditka, N. F. Osman, M. Nabil, Zoltan Erdelyi
Summary: The relationship between AC conductivity, sheet resistance measurements, and microhardness with Cu interlayer thickness of conductive ZnO/Cu/ZnO thin films is investigated. ZnO layer is prepared via atomic layer deposition (ALD), while Cu interlayer is deposited by DC magnetron sputtering. The combination of ZnO/Cu/ZnO with constant ZnO thickness and variable Cu interlayer thickness shows enhanced electrical and mechanical properties.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Siavash Bakhtiarnia, Saeed Sheibani, Alain Billard, Hui Sun, Eric Aubry, Mohammad Arab Pour Yazdi
Summary: This study investigated the effects of thickness on the morphology, crystal structure, composition, optical and photocatalytic properties of nanoporous BiVO4 thin films deposited using reactive DC magnetron sputtering. The results show that film thickness significantly influences the performance of the thin films, impacting porosity, bandgap, crystallographic plane orientation, and photodegradation efficiency under visible light.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Yantong Guo, Xunliang Hu, Ruixue Sun, Xiaoyan Wang, Bien Tan
Summary: Photocatalytic hydrogen evolution through water splitting using covalent triazine frameworks (CTFs) offers a promising route for solar energy conversion. However, the typical powder form of CTF-based photocatalysts poses challenges in recycling and scale-up applications. To address this limitation, CTF films were developed by in-situ growth polycondensation on glass substrates, demonstrating exceptional photocatalytic activity, stability, and recyclability. These films show a high hydrogen evolution rate and hold potential for green energy conversion and photocatalytic devices.
Article
Materials Science, Multidisciplinary
Navid Chapman, Mingyu Chapman, William B. Euler
Summary: In this study, a predictive film thickness model based on an accepted equation of state was applied to the spin-coating of sub-micron poly(methylmethacrylate) viscous thin films from toluene. The concentration effects on density and dynamic viscosity of the spin-coating solution were closely examined. Process mapping was utilized to generate a three-dimensional design space for controlling film thickness.
Article
Chemistry, Analytical
Victor V. Petrov, Victor V. Sysoev, Irina O. Ignatieva, Irina A. Gulyaeva, Maria G. Volkova, Alexandra P. Ivanishcheva, Soslan A. Khubezhov, Yuri N. Varzarev, Ekaterina M. Bayan
Summary: Thin nanocomposite films of Co3O4-ZnO were synthesized by solid-phase pyrolysis. The films show a wurtzite phase of ZnO and a spinel structure of Co3O4. Increasing annealing temperature and Co3O4 concentration result in larger crystallite sizes. The optical properties and charge carrier mobility of the films are influenced by the Co3O4 content. Photosensors based on the films exhibit enhanced photoresponse in specific wavelength ranges.
Article
Engineering, Electrical & Electronic
Mamadou D. Coulibaly, Caroline Borderon, Raphael Renoud, Hartmut W. Gundel
Summary: This study investigates the contribution of ferroelectric domain walls to the permittivity in a PbZrO3 antiferroelectric thin film. The lattice contribution to the permittivity increases with the polarization electric field, and two additional small peaks are observed. The vibration and pinning/unpinning contributions of the domain walls exhibit only ferroelectric butterfly loops, indicating that ferroelectricity does not completely disappear.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Thermodynamics
Yanhong Sun, Wenjie Chen, Jinli Lu, Changlong Wang
Summary: In this study, experimental investigation on the flow and heat transfer characteristics of a thin liquid film in micro circular tubes with an inner diameter of 0.5 mm was conducted. The results showed that the temperature and pressure fluctuation was consistent with the generation of bubble clusters, providing insights into the mechanism of flow boiling instability. The characteristics of void fraction, such as the duration of bubbles and liquid slugs, were obtained from the dynamic distribution diagram of the liquid film thickness, and the experimental data showed a good agreement with the homogeneous model. The temporary variation of the thin liquid film offered an opportunity to probe the physics of bubble dynamics and instability during flow boiling.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Engineering, Electrical & Electronic
Yuancong Wu, Y. H. Liu, Shuang Liu, Q. Yu, T. P. Chen, Y. Liu
ELECTRONICS LETTERS
(2020)
Article
Engineering, Electrical & Electronic
Jianxun Sun, Juan Boon Tan, Tupei Chen
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2020)
Article
Engineering, Electrical & Electronic
Jianxun Sun, Juan Boon Tan, Tupei Chen
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2020)
Article
Computer Science, Artificial Intelligence
G. C. Qiao, S. G. Hu, T. P. Chen, L. M. Rong, N. Ning, Q. Yu, Y. Liu
Article
Engineering, Electrical & Electronic
Rui Guo, YuanCong Wu, ShaoGang Hu, Qi Yu, Tupei Chen, Yang Liu
Summary: This work introduces an LC-VCO based PLL frequency synthesizer with a neural network based loop bandwidth tracking technique, which can maintain a constant loop bandwidth over different operating frequencies.
IEICE ELECTRONICS EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Yuanbo Li, Jianxun Sun, Teddy Salim, Rongyue Liu, Tupei Chen
Summary: A high-mobility transparent Indium-Gallium-Zinc-Oxide (IGZO) thin-film transistor (TFT) with sputtered AlOx passivation layer was reported, showing improved field-effect mobility, on/off current ratio, and driving current. The formation of an interfacial layer between the IGZO and AlOx layers was crucial in enhancing the electrical performance. Reliability tests, including long-term exposure and positive bias illumination stress, also exhibited improved results.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2021)
Article
Physics, Applied
Shuang Liu, Yuancong Wu, Canlong Xiong, Yihe Liu, Jing Yang, Q. Yu, S. G. Hu, T. P. Chen, Y. Liu
Summary: PIM technology enhances the performance of RC systems, demonstrated in this work using a PIM chip platform. Nonlinear dynamic system predictions and recognition tasks were carried out, saving 50% energy and requiring fewer operations compared to traditional RC systems.
APPLIED PHYSICS LETTERS
(2021)
Article
Computer Science, Artificial Intelligence
S. G. Hu, G. C. Qiao, T. P. Chen, Q. Yu, Y. Liu, L. M. Rong
Summary: In this study, a SNN based on STDP for online learning with weight quantization/binarization was developed. The quantized SNN achieved high recognition accuracy on the MNIST dataset with reduced storage requirements and improved computing efficiency. This approach can significantly save hardware costs and provide a trade-off between computational cost and performance.
NEURAL COMPUTING & APPLICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Y. B. Li, J. Zhang, J. X. Sun, T. P. Chen
Summary: This study aims to find a suitable HfO2-based resistive random-access memory (RRAM) structure for large-area applications and successfully inserts an ultrathin Al2O3 layer to achieve stable operations at low current levels.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2021)
Article
Nanoscience & Nanotechnology
Y. H. Liu, L. Chen, X. W. Li, Y. C. Wu, S. Liu, J. J. Wang, S. G. Hu, Q. Yu, T. P. Chen, Y. Liu
Summary: This study proposes a lightweight automatic epilepsy detection system based on a neuromorphic chip, utilizing a neural network model for high-accuracy detection without the need for prior knowledge. The system shows high classification accuracy in tests and offers the possibility of epilepsy detection in wearable or portable devices.
Article
Multidisciplinary Sciences
Y. A. Liu, L. Chen, X. W. Li, Y. L. Liu, S. G. Hu, Q. Yu, T. P. Chen, Y. Liu
Summary: This paper proposes an advanced encryption standard (AES) cryptosystem based on memristive neural network. The proposed algorithm shows higher security and robustness compared to conventional AES.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Biomedical
Shuang Liu, J. J. Wang, J. T. Zhou, S. G. Hu, Q. Yu, T. P. Chen, Y. Liu
Summary: In this article, a spiking neural network (SNN) based on both SRAM processing-in-memory (PIM) macro and on-chip unsupervised learning with Spike-Time-Dependent Plasticity (STDP) is presented. The co-design of algorithm and hardware improves area and energy efficiency. The proposed macro utilizes charge sharing of capacitors for fully parallel operations and a programmable high-precision PIM threshold generator is designed to achieve low DNL and high linearity. With the combination of the hardware-friendly STDP algorithm, parallel WLs and PBLs, unsupervised learning and MNIST dataset recognition are realized.
IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS
(2023)
Article
Chemistry, Analytical
Hongzhe Wang, Junjie Wang, Hao Hu, Guo Li, Shaogang Hu, Qi Yu, Zhen Liu, Tupei Chen, Shijie Zhou, Yang Liu
Summary: This paper proposes an RRAM PIM accelerator architecture that does not use ADCs and DACs. Additionally, no additional memory usage is required to avoid the need for a large amount of data transportation in convolution computation. Partial quantization is introduced to reduce the accuracy loss. The proposed architecture can substantially reduce the overall power consumption and accelerate computation. The simulation results show that the image recognition rate for the CNN algorithm can reach 284 frames per second at 50 MHz using this architecture. The accuracy of the partial quantization remains almost unchanged compared to the algorithm without quantization.
Article
Chemistry, Multidisciplinary
Yuanbo Li, Tupei Chen, Xin Ju, Teddy Salim
Summary: This study presents the fabrication of a transparent thin film transistor (TFT) using InGaZnO and TaOx, which exhibits various synaptic behaviors and high responsivity to light, indicating potential applications in neuromorphic systems.
Article
Computer Science, Information Systems
Jianxun Sun, Yuan Bo Li, Yiyang Ye, Jun Zhang, Gang Yih Chong, Juan Boon Tan, Zhen Liu, Tupei Chen