Article
Materials Science, Multidisciplinary
Yingfeng He, Zhengying Si, Yu 'ang Shi, Huiyun Wei, Mingzeng Peng, Xinhe Zheng
Summary: Gallium nitride (GaN) thin films were grown on stainless steel substrate with Al2O3 buffer using plasma-enhanced atomic layer deposition at low temperature (& LE;290 & DEG;C). The GaN films exhibited a polycrystalline structure with a strong (002) preferential orientation. The refractive index of the films was determined as 2.30 at 633 nm using Spectroscopic Ellipsometry. This study provides a new approach for achieving high-quality GaN on metal substrates, which is promising for future applications of GaN-based devices on metal substrates.
Article
Chemistry, Physical
Muhammad Iznul Hisyam, Rizuan Norhaniza, Ahmad Shuhaimi, Marwan Mansor, Adam Williams, Mohd Rofei Mat Hussin
Summary: To improve the quality of GaN-on-Si and enhance the performance of optoelectronic devices, a pulse atomic-layer epitaxy (PALE) AlN buffer layer is introduced. The study investigates the effect of different cycle numbers of AlN PALE buffer layer on the quality of GaN grown on Si(111) substrate. Various characterization techniques reveal that the AlN PALE layer reduces surface cracks, improves structural properties, and decreases tensile strain in the GaN epilayers.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Physical
C. M. Furqan, Jacob Y. L. Ho, H. S. Kwok
Summary: This article reports the growth of GaN thin film on low-cost electronic substrate using magnetron sputtering method. Various characterization techniques were used to explore the optical and structural properties, revealing the effects of different growth parameters on the film properties. XRD studies, raman spectroscopy, as well as mu-PL and optical transmittance experiments provided insights into the thin film properties under different growth conditions.
SURFACES AND INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Zhe (A. ) Jian, Kai Sun, Stefan Kosanovic, Christopher J. Clymore, Umesh Mishra, Elaheh Ahmadi
Summary: Wafer bonding of β-Ga2O3 and N-polar GaN single crystal substrates, achieved by adding ZnO as a glue interlayer, resulted in fully bonded wafers without Newton rings. Temperature-dependent current-voltage measurements revealed the impact of post-annealing temperature on the electrical and structural characteristics of the bonded samples. Annealing the bonded wafers at 1100°C in N-2,N- environment consistently produced ohmic-like characteristics, attributed to the crystallization of ZnO and diffusion of Ga into ZnO. This work demonstrates promising wafer bonding of β-Ga2O3 and GaN, with potential applications in high-frequency and high-power devices.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Physics, Applied
Xin Chen, Yaozong Zhong, Shumeng Yan, Xiaolu Guo, Hongwei Gao, Xiujian Sun, Haodong Wang, Fangqing Li, Yu Zhou, Meixin Feng, Ercan Yilmaz, Qian Sun, Hui Yang
Summary: The characteristics of an AlGaN/GaN high-electron-mobility transistor buffer structure are studied and optimized by employing an AlN/GaN superlattice (SL) structure. The influence of buffer traps on carrier transport behaviors and electrical performance for SL buffer structures under a high electric field is analyzed. The AlN/GaN SL buffer structures are further optimized with various AlN/GaN thickness ratios and their total thickness, achieving a high breakdown voltage and suppressing the buffer trapping effect.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Aniruddhan Gowrisankar, Vanjari Sai Charan, Hareesh Chandrasekar, Anirudh Venugopalarao, R. Muralidharan, Srinivasan Raghavan, Digbijoy N. Nath
Summary: This article reports the performance of compensation doping-free aluminum gallium-nitride (AlGaN)/gallium nitride (GaN) high-electron mobility transistors (HEMTs) on Silicon for RF applications using a polarization-graded buffer scheme. A resistive buffer is engineered using a compositionally reverse-graded AlGaN (g-AlGaN) layer, eliminating the need for compensation dopants. Transistors with 0.35 μm gate length and source-connected field plates showed a maximum drain current of 1 A/mm and OFF-state breakdown voltage of 144 V. RF performance of HEMTs on these polarization-graded buffers achieved a peak ft/fmax of 49.2/86.4 GHz.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Chemistry, Physical
Lukasz Janicki, Ryszard Korbutowicz, Mariusz Rudzinski, Piotr Michalowski, Sebastian Zlotnik, Milosz Grodzicki, Sandeep Gorantla, Jaroslaw Serafinczuk, Detlef Hommel, Robert Kudrawiec
Summary: This study comprehensively investigates the structural and optical properties of GaN subjected to three oxidation modes. The results reveal that all modes lead to the growth of beta-phase Ga2O3, but they differ in surface morphology, growth rate, and oxygen diffusion behavior. Only the vapor oxidation process does not degrade the material underneath the oxide layer.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Muhammad Umair Khan, Chaudhry Muhammad Furqan, Jungmin Kim, Sobia Ali Khan, Qazi Muhammad Saqib, Mahesh Y. Chougale, Rayyan Ali Shaukat, Moon Hee Kang, Nobuhiko P. Kobayashi, Jinho Bae, Hoi-Sing Kwok
Summary: This study focuses on the material and design concept to achieve a one-directional engineered resistive switching memory device to reduce crosstalk effect for electronic synapses. The asymmetric multistate resistive switching behavior and synaptic spike-rate-dependent plasticity and spike-timing-dependent plasticity were validated through simulation and experiments.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Rui Liu, Jiawei Si, Qipu Lv, Cancheng Xiao, Ziye Di, Lei Zhao, Liancheng Wang, Lei Zhang
Summary: Continuous c-axis-oriented GaN films were synthesized using a CVD method with ZnO as the intermediate buffer layer. These films exhibited high crystal quality and low surface roughness due to the similar crystal structure and low lattice mismatches between GaN and ZnO. The UV photodetector based on these films showed high responsivity, fast response times, and good thermal stability.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Biochemistry & Molecular Biology
Shicong Jiang, Wan-Yu Wu, Fangbin Ren, Chia-Hsun Hsu, Xiaoying Zhang, Peng Gao, Dong-Sing Wuu, Chien-Jung Huang, Shui-Yang Lien, Wenzhang Zhu
Summary: The application of (In, Al, Ga)N materials in photovoltaic devices has attracted much attention. However, to deposit high-quality GaN material as a foundation is essential. Plasma-enhanced atomic layer deposition (PEALD) combines the advantages of ALD process with plasma utilization and has been used to deposit thin films with various requirements. In this study, NH3-containing plasma was used to eliminate the residual oxygen during the growth of GaN films, which significantly improved the quality of the films. The plasma power controlled NH2, NH, and H radicals showed strong influence on the oxygen content, growth rate, crystallinity, and surface roughness of the GaN films.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Computer Science, Information Systems
Wei Lin, Maojun Wang, Haozhe Sun, Bing Xie, Cheng P. Wen, Yilong Hao, Bo Shen
Summary: This paper proposes an HEMT structure with a source-connected p-GaN embedded in a carbon-doped semi-insulating buffer to suppress the buffer-induced current collapse effect. Two-dimensional transient simulation demonstrates the successful suppression of current collapse in SCPG-HEMTs compared to conventional HEMTs. The mechanism of ejecting holes from SCPG into the high resistive buffer layer after off-state stress is illustrated to potentially solve the buffer-induced degradation of dynamic on-resistance in GaN power devices.
Article
Materials Science, Multidisciplinary
Wei-Hao Lee, Fong-Jyun Jhong, Yu-Tung Yin, Chun-Yi Chou, Jing-Jong Shyue, Miin-Jang Chen
Summary: This paper reports on the significant enhancement of the crystalline quality of nanoscale GaN thin films using a large-area and rapid electron beam annealing technique. The results demonstrate high-quality GaN epilayers with smooth surfaces, indicating potential for various applications.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Physics, Applied
Kazimieras Badokas, Arunas Kadys, Juras Mickevicius, Ilja Ignatjev, Martynas Skapas, Sandra Stanionyte, Edvinas Radiunas, Giedrius Juska, Tadas Malinauskas
Summary: This study presents the growth of a GaN epilayer using remote epitaxy via graphene on a GaN/sapphire template and discusses the advantages of using monolayer graphene. The research focuses on analyzing GaN seed formation on the graphene interface and optimizing growth parameters to enhance the crystalline quality of the epilayer.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Denis Petrovich Borisenko, Alexander Sergeevich Gusev, Nikolay Ivanovich Kargin, Petr Leonidovich Dobrokhotov, Alexey Afanasievich Timofeev, Vladimir Arkhipovich Labunov, Mikhail Mikhailovich Mikhalik, Konstantin Petrovich Katin, Mikhail Mikhailovich Maslov, Pavel Sergeevich Dzhumaev, Ivan Vladimirovich Komissarov
Summary: In this study, SLG/FLG and MLG samples were obtained using the CVD method, and plasma-assisted molecular beam epitaxy was used for GaN graphene-assisted growth. The effect of graphene defectiveness and thickness on the quality of the GaN epilayers was investigated. The results showed that bilayer graphene provided optimal conditions for the growth of GaN/AlN.
APPLIED SCIENCES-BASEL
(2022)
Article
Crystallography
Piotr Mazur, Agata Sabik, Rafal Lewandkow, Artur Trembulowicz, Milosz Grodzicki
Summary: In this work, a niobium nitride film was obtained using n-GaN(1000) surface as the source of nitrogen atoms through a surface-mediated nitridation technique. The deposition of niobium film on GaN followed by sample annealing resulted in the formation of a niobium nitride compound containing Nb from the thin film and N atoms from the substrate. The structural, chemical, and surface properties of both the GaN substrate and NbNx films were studied using in-situ techniques.
Article
Energy & Fuels
Maria Recaman Payo, Yuandong Li, Richard Russell, Sukhvinder Singh, Izabela Kuzma Filipek, Filip Duerinckx, Jozef Szlufcik, Jef Poortmans
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2020)
Article
Spectroscopy
D. S. Sutar, Nirvikar Kushwaha, Shravan K. Appani, S. S. Major
JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA
(2020)
Article
Materials Science, Multidisciplinary
Shravan K. Appani, Ashok Kumar Yadav, D. S. Sutar, S. N. Jha, D. Bhattacharyya, S. S. Major
Article
Chemistry, Physical
Pavan K. Narayanam, S. S. Major
Summary: The GO-TiO2 nanocomposite sheets were transferred onto solid substrates using Langmuir-Blodgett method and subjected to heat treatment to obtain rGO-wrapped TiO2 nanostructures. The heat treatment conditions significantly influenced the reduction of GO, crystalline phases of TiO2, and the development of composite nanostructures. Photocatalytic studies showed strong dependence of photo-degradation on the morphology of the nanocomposite sheets.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Engineering, Electrical & Electronic
Praloy Mondal, Shravan K. Appani, D. S. Sutar, S. S. Major
Summary: A systematic study on Ga-doped ZnO films deposited by radio frequency reactive magnetron co-sputtering of Zn and GaAs has been conducted to realize n-GZO/p-Si heterojunction diodes. It has been found that the doping level and conductivity of the GZO layer can be controlled by the partial pressure of oxygen in the sputtering atmosphere, leading to the fabrication of diodes with improved performance. The presence of nearly complete c-axis orientation, absence of oxygen vacancies, and chemisorbed oxygen at the grain boundaries in the GZO layer appear to enhance the diode performance.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Physics, Applied
M. Monish, S. S. Major
Summary: This study investigated the properties of epitaxial GaN films grown at different nitrogen partial pressures, revealing parameters such as lattice strain and dislocation density through various testing methods. The research found that the strain and stress of the films mainly depend on the nitrogen partial pressure and the ratio of nitrogen to argon content.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Mohammad Monish, C. Nayak, D. S. Sutar, S. N. Jha, D. Bhattacharyya, S. S. Major
Summary: Undoped GaN films were epitaxially grown on c-sapphire by rf magnetron reactive sputtering of GaAs at different N-2 percentages in Ar-N-2 sputtering atmosphere. The conductivity of the films increased with a decrease of N-2 percentage, accompanied by changes in N/Ga ratio and the presence of different types of vacancies in the films. The study also identified the main sources of n-type conductivity in sputtered GaN films and the factors affecting the conductivity levels.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2021)
Article
Energy & Fuels
Valerie Depauw, Richard Russell, Sukhvinder Singh, Maria Recaman, Monica Aleman, Shruti Jambaldinni, Filip Duerinckx, Ivan Gordon, Jozef Szlufcik, Yaser Abdulraheem, Jef Poortmans
Summary: Contactless plating with electroless solutions can provide high-efficiency contacts with low silver content and self-alignment. However, the combination of surface activation and immersion plating with nickel can lead to decreases in V-oc and fill factor. The impact of immersion plating on the microstructure of the plated silicon surface must be carefully studied to prevent electrical degradation.
IEEE JOURNAL OF PHOTOVOLTAICS
(2021)
Article
Energy & Fuels
Sukhvinder Singh, Patrick Choulat, Jonathan Govaerts, Arvid van der Heide, Valerie Depauw, Filip Duerinckx, Ronald Naber, Martijn Lenes, Marten Renes, Loic Tous, Jef Poortmans
Summary: This work demonstrates the integration of polysilicon-based passivating contacts in plated bifacial n-type PERT solar cells, showing the potential for full exploitation of passivated contacts. Successful co-plating of n-poly and p-poly on both sides of n-PERT cells was achieved, with selective patterning used to mitigate parasitic absorption losses. Different patterning methods for front side polysilicon were compared, with a best efficiency of 22.7% achieved on large area n-type Cz. These cells have also passed thermal cycling tests and show potential for efficiencies above 24%.
PROGRESS IN PHOTOVOLTAICS
(2022)
Article
Energy & Fuels
Merit Firat, Hariharsudan Sivaramakrishnan Radhakrishnan, Sukhvinder Singh, Filip Duerinckx, Maria Recaman Payo, Loic Tous, Jef Poortmans
Summary: Poly-Si/SiOx passivating contacts are important for highly-efficient Si solar cells. Their fabrication usually involves extra high-temperature processes, but a fired passivating contact (FPC) approach eliminates this step. The compatibility of FPCs with metallization techniques is still a challenge.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Engineering, Electrical & Electronic
Mohammad Monish, S. S. Major
Summary: Si-doped GaN films were grown on c-sapphire substrate by rf magnetron reactive co-sputtering under different N2 percentages. The Si content, N/Ga ratio, lattice parameters, and the density, stress, and strain of defects in the films were found to be significantly influenced by the N2 percentage.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Energy & Fuels
Nina Plankensteiner, Amedeo Agosti, Jonathan Govaerts, Rico Rupp, Sukhvinder Singh, Jef Poortmans, Philippe M. Vereecken, Joachim John
Summary: Green hydrogen is a valuable resource for energy storage and industrial use. A commercially relevant PV-EC system combining standard silicon technology and low-cost AEM electrolysis with high-surface-area nickel nanomesh electrodes has been developed. The system demonstrates stable hydrogen production and high efficiency under large current densities.
Article
Chemistry, Physical
Nina Plankensteiner, Rico Rupp, Patrick Steegstra, Sukhvinder Singh, Jorge Giribet Canto, Siggi Wodarz, Martijn J. W. Blom, Joachim John, Maarten Mees, Philippe M. Vereecken
Summary: Nanomeshes are interconnected 3D nanowire-networks with high surface area and porosity, which have potential applications in various fields. By integrating nanomeshes with an open support grid, they can be used as freestanding electrodes in electrochemical flow cells, showing superior performance compared to existing technologies.
MATERIALS TODAY ENERGY
(2022)
Proceedings Paper
Physics, Condensed Matter
M. Monish, Shyam Mohan, D. S. Sutar, S. S. Major
DAE SOLID STATE PHYSICS SYMPOSIUM 2019
(2020)
Proceedings Paper
Energy & Fuels
Sukhvinder Singh, Patrick Choulat, Filip Duerinckx, Maria Recaman Payo, Ronald Naber, Martijn Lenes, Loic Tous, Jef Poortmans
2020 47TH IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE (PVSC)
(2020)
