Article
Crystallography
Moe Shimokawa, Shohei Teramura, Shunya Tanaka, Tomoya Omori, Kazuki Yamada, Yuya Ogino, Ayumu Yabutani, Sho Iwayama, Kosuke Sato, Motoaki Iwaya, Tetsuya Takeuchi, Satoshi Kamiyama, Isamu Akasaki, Hideto Miyake
Summary: In the growth of Al0.6Ga0.4N, the formation of loop dislocations during three-dimensional growth reduces the dislocation density effectively. The study found that the spontaneous nucleation behavior of Al0.6Ga0.4N strongly depends on the fabrication temperature of homo-AlN, leading to successful reduction of dislocation density to as low as 5.8 x 10(8) cm(-2).
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Chemistry, Multidisciplinary
Hua-Chiang Wen, Ssu-Kuan Wu, Cheng-Wei Liu, Jin-Ji Dai, Wu-Ching Chou
Summary: The nanotribological properties of AlxGa1-xN epitaxial films grown on low-temperature-grown GaN/AlN/Si substrates were investigated. It was found that the Al compositions played a crucial role in determining the strength of bonding forces and shear resistance. The measured friction coefficient (mu) values decreased with increasing Al compositions, indicating a transition from brittleness to ductility in the AlxGa1-xN system.
Article
Crystallography
Patrick Haeuser, Christian Blumberg, Lisa Liborius, Werner Prost, Nils Weimann
Summary: This paper presents a study on position-defined Al-polar AlN nucleation for growing ordered Ga-polar GaN nanowire arrays, which could be used in future nanowire-based devices. By adjusting the placement pattern of Si-pillars, the collection area of Ga-adatoms per nanowire can be varied, allowing for control of wire size and pitch.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Chemistry, Physical
Pojung Lin, Jiazhe Liu, Hongche Lin, Zhiyuan Chuang, Wenching Hsu, Yiche Chen, Poliang Liu, Rayhua Horng
Summary: In this study, GaN-based epitaxial structures were grown on high-resistivity silicon (HRSi) substrates by met-alorganic chemical vapor deposition. The p-type parasitic channels generated at the interfaces of the aluminum nitride (AlN) nucleation layers and HRSi substrates were characterized. A 2-nm thick silicon nitride (SiNx) layer was used to suppress the Al diffusion and prevent the generation of p-type parasitic channels. The insertion loss of the optimized structure was only 0.04 dB/mm higher than that of the annealed HRSi substrate at 10 GHz.
SURFACES AND INTERFACES
(2023)
Article
Crystallography
Dadi Wang, Zhibin Liu, Yanan Guo, Jianchang Yan, Jinmin Li, Junxi Wang
Summary: In this study, a silane-pretreatment method was developed to improve the growth mode and crystalline quality of n-Al0.6Ga0.4N on a high-temperature-annealing AlN/sapphire template. The use of SiH4 pretreatment disrupted the pseudo-crystal epitaxy of n-Al0.6Ga0.4N, resulting in 3D growth at the AlGaN/AlN interface. This method also led to a significant reduction in threading dislocations density and paves the way for the preparation and improvement of efficient deep ultraviolet emitters.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Multidisciplinary Sciences
Kentaro Nagamatsu, Takumi Miyagawa, Atsushi Tomita, Hideki Hirayama, Yuusuke Takashima, Yoshiki Naoi
Summary: This article discusses the use of deep ultraviolet light-emitting diodes for virus inactivation applications. It was found that the growth temperature of the AlN underlying layer was limited in conventional MOVPE methods, and using a flat sapphire substrate led to a high density of dislocations in the AlN layer. By utilizing high temperature and gas flow velocity MOVPE, high-temperature crystal growth of AlN at 1700 degrees C was achieved. The study also observed a decrease in growth rate at AlN growth temperatures exceeding 1550 degrees C.
SCIENTIFIC REPORTS
(2023)
Article
Crystallography
Toru Akiyama, Takumi Ohka, Katsuya Nagai, Tomonori Ito
Summary: Through ab initio electronic structure calculations, a systematic investigation of the adsorption behavior of Al and N adatoms on vicinal AlN (0001) surface under metal-organic vapor phase epitaxy (MOVPE) growth conditions was conducted. It was found that the vicinal surface with hydrogen-terminated N atom and NH2 was the most stable under N-rich conditions, while the surface with hydrogen-terminated N atom and NH2 at the step edge was favorable over a wide range of Al chemical potential. The adsorption energy of Al adatoms at the step edge was much lower than that in the terrace region, indicating easier incorporation of Al adatoms into the step edge.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Crystallography
Marzieh Bakhtiary-Noodeh, Theeradetch Detchprohm, Russell D. Dupuis
Summary: This study aims to investigate the unintentional impurity incorporation in GaN epitaxial layers and optimize the growth conditions to reduce background impurity concentrations. The results show that the unintentional incorporation of carbon and silicon impurities is highly dependent on the growth parameters. The use of TEG precursor can reduce the carbon concentration, while the lowest concentration can be achieved with TMG precursor under optimized conditions. Similarly, the lowest background silicon concentration can be achieved with TMG precursor under specific conditions.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Nanoscience & Nanotechnology
Katarzyna Ludwiczak, Aleksandra Krystyna Dabrowska, Johannes Binder, Mateusz Tokarczyk, Jakub Iwanski, Boguslawa Kurowska, Jakub Turczynski, Grzegorz Kowalski, Rafal Bozek, Roman Stepniewski, Wojciech Pacuski, Andrzej Wysmolek
Summary: Transition metal dichalcogenides (TMDs) are materials with intriguing optical properties, especially when thinned down to a monolayer. By transferring TMD onto hexagonal boron nitride (hBN), significant improvements in optical and electrical properties can be achieved. A new epitaxial technique has been developed to directly grow high optical quality MoSe2 on an entire 2-inch wafer.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Crystallography
J. E. Ruiz, D. Lackner, P. L. Souza, F. Dimroth, J. Ohlmann
Summary: The growth of dilute nitrides with metal organic chemical vapor phase epitaxy (MOVPE) faces challenges of low N-incorporation and high impurity levels of carbon and hydrogen. Investigation into N and C-incorporation in GaNxAs1-x showed that N-incorporation is proportional to the N/As ratio, while C primarily comes from group-III-methyl groups.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Crystallography
Atsushi Yamada, Junya Yaita, Norikazu Nakamura, Junji Kotani
Summary: The research demonstrates that low-sheet-resistance HEMTs can be achieved by using a strain-controlled high-Al-composition AlGaN barrier. It was found that growing an AlGaN barrier with nitrogen as a carrier gas increases dislocation density and reduces strain, leading to improved electron mobility. Additionally, the use of an AlN spacer helps prevent dislocation and impurity scattering, resulting in successful fabrication of low-sheet-resistance HEMT structures with high Al composition.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Materials Science, Multidisciplinary
Wouter Mortelmans, Stefan De Gendt, Marc Heyns, Clement Merckling
Summary: The application of new materials in nanotechnology, particularly 2D chalcogenides, holds promise for groundbreaking innovations in the semiconductor industry. However, the integration of these materials poses challenges, limiting their usage to research laboratories. Achieving epitaxial growth of large-area, single-crystalline 2D chalcogenides is crucial for meeting industry demands.
APPLIED MATERIALS TODAY
(2021)
Article
Crystallography
Alice Hospodkova, Frantisek Hajek, Tomas Hubacek, Zuzana Gedeonova, Pavel Hubik, Jirf J. Mares, Jirf Pangrac, Filip Dominec, Karla Kuldova, Eduard Hulicius
Summary: Although various aspects of GaN high electron mobility transistor (HEMT) structure have been extensively studied, such as buffer layer architecture, AlGaN barrier, surface passivation, and dielectric choice, little attention has been given to optimize the GaN channel technology. In this work, we demonstrate that by optimizing the channel technology, electron mobility can be significantly improved. We investigated the influence of technological parameters on the transport properties of a series of GaN layers mimicking a HEMT channel. We focused on the layer growth using TEG precursor and examined parameters such as reactor atmosphere, growth temperature, growth rate influenced by precursor concentration, and reactor pressure. By using optimized growth parameters for the HEMT structure, we successfully increased the electron mobility in 2DEG by 30%.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Engineering, Electrical & Electronic
A. Azizur Rahman, Nirupam Hatui, Carina B. Maliakkal, Priti Gupta, Jayesh B. Parmar, Bhagyashree A. Chalke, Arnab Bhattacharya
Summary: The study found that the choice of nucleation layer significantly affects the properties of semipolar GaN epilayers. Direct growth of (112 over bar 2) GaN without buffer layers provided the best crystal quality and relatively enhanced near-band-edge photoluminescence emission.
JOURNAL OF ELECTRONIC MATERIALS
(2021)
Article
Crystallography
Ta-Shun Chou, Saud Bin Anooz, Raimund Grueneberg, Natasha Dropka, Wolfram Miller, Thi Thuy Vi Tran, Jana Rehm, Martin Albrecht, Andreas Popp
Summary: This study demonstrates the use of Random Forest, a machine learning approach, for predicting the growth rate of beta-Ga2O3 in metal-organic vapor phase epitaxy (MOVPE) by analyzing its growth process on sapphire. The proposed model can effectively evaluate the complex non-linear dependencies among growth parameters and optimize them to achieve the optimal growth rate. It achieves a high predictive power with a coefficient of determination (R-2) of 0.95 and 0.92 for the training and testing sets, respectively. The model's outcome is applicable to both homoepitaxial and heteroepitaxial processes, as well as different substrate orientations.
JOURNAL OF CRYSTAL GROWTH
(2022)
Article
Physics, Applied
Yosuke Sasama, Taisuke Kageura, Katsuyoshi Komatsu, Satoshi Moriyama, Jun-ichi Inoue, Masataka Imura, Kenji Watanabe, Takashi Taniguchi, Takashi Uchihashi, Yamaguchi Takahide
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Chemistry, Inorganic & Nuclear
Fumio Kawamura, Hidenobu Murata, Masataka Imura, Naoomi Yamada, Takashi Taniguchi
Summary: A novel ternary nitride semiconductor CaSnN2 with a rock-salt-type structure was synthesized, along with the systematic study of II-Sn-N-2 (II = Ca, Mg, Zn) semiconductors. Differences in structure and properties were revealed, showing CaSnN2 and MgSnN2 have band gaps suitable for various applications. These inexpensive and nontoxic semiconductors have potential as replacements for cadmium-based materials in pigments, as well as for InxGa1-xN semiconductors in emitting devices and photovoltaic absorbers.
INORGANIC CHEMISTRY
(2021)
Article
Physics, Applied
Huanying Sun, Xiulin Shen, Liwen Sang, Masataka Imura, Yasuo Koide, Jianqiang You, Tie-Fu Li, Satoshi Koizumi, Meiyong Liao
Summary: In this study, the thermal mismatch induced stress was precisely measured using the dynamic resonance method on a single-crystal diamond microelectromechanical resonator. The results indicated a linear relationship between the resonance frequency and the induced stress, with a stress resolution as precise as 10(4) Pa, which is three orders of magnitude better than traditional Raman and X-ray diffraction methods.
APPLIED PHYSICS EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Xiulin Shen, Kongping Wu, Huanying Sun, Liwen Sang, Zhaohui Huang, Masataka Imura, Yasuo Koide, Satoshi Koizumi, Meiyong Liao
Summary: This study investigates the Young's modulus of (100) oriented single-crystal diamond from room temperature to 700 degrees C, using a dynamic resonance frequency method based on experimental and theoretical approaches. The results show that the Young's modulus of SCD follows the same model as temperature increases, providing a convenient and accurate method to measure the dependency of SCD Young's modulus on temperature.
DIAMOND AND RELATED MATERIALS
(2021)
Article
Physics, Applied
Hironori Okumura, Riena Jinno, Akira Uedono, Masataka Imura
Summary: This study investigated the optical and electrical properties of silicon-implanted c-plane and m-plane alpha-Al2O3 substrates. Multiple-energy silicon implantation achieved a box profile with a silicon concentration of 3 x 10(19) cm(-3), leading to a decrease in oxygen-vacancy-related defects after annealing at 1300 degrees C. The surface roughness of the samples was improved to less than 1 nm after thermal annealing, and current-voltage measurements showed 0.6 mu A at a bias of 100 V for the silicon-implanted m-plane alpha-Al2O3 sample after annealing at 1300 degrees C.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Xiulin Shen, Huanying Sun, Liwen Sang, Masataka Imura, Yasuo Koide, Satoshi Koizumi, Meiyong Liao
Summary: By utilizing radio-frequency magnetron sputtering, SCD MEMS resonators integrated with TbDyFe thin film were successfully fabricated, showing improved sensing performance after annealing at 550 degrees C for 3 hours and achieving a high magnetic sensitivity of 5.34 Hz mT(-1). The advantage of giant magnetostriction of the TbDyFe thin film enabled the estimated minimum detectable force to reach 1.65 x 10(-14) N.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Takashi Tsuchiya, Makoto Takayanagi, Kazutaka Mitsuishi, Masataka Imura, Shigenori Ueda, Yasuo Koide, Tohru Higuchi, Kazuya Terabe
Summary: The study demonstrates that the electric double layer effect with different solid electrolytes can be evaluated using hydrogenated diamond-based transistors, where the transistor with Li-Si-Zr-O solid electrolyte shows significant EDL-induced hole density modulation, while the one with Li-La-Ti-O solid electrolyte shows minimal enhancement, possibly due to charge neutralization in the LLTO caused by variation in the valence state of the Ti ions.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Physics, Applied
Shunichiro Yata, Mari Mizutani, Kaede Makiuchi, Fumio Kawamura, Masataka Imura, Hidenobu Murata, Junjun Jia, Naoomi Yamada
Summary: The charge-carrier transport properties of MgSnN2 films were studied, and it was found that the contribution of grain boundary scattering to electron transport was negligible for films with n(e) > 8 x 10^(20) cm^(-3), but became unignorable with decreasing n(e). The study also determined the conduction-band effective mass for the first time, showing that the conduction-band dispersion may be affected by the cation composition x.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Masataka Imura, Hideki Inaba, Takaaki Mano, Nobuyuki Ishida, Fumihiko Uesugi, Yoko Kuroda, Yoshiko Nakayama, Masaki Takeguchi, Yasuo Koide
Summary: The structural quality of AlN layers grown on a sapphire substrate using metal-organic vapor phase epitaxy (MOVPE) was significantly improved by post-growth annealing, resulting in a smoother surface and better crystal quality. This work has implications for the industrial production of AlxGa1-xN-based ultraviolet light-emitters.
Article
Engineering, Electrical & Electronic
Yosuke Sasama, Taisuke Kageura, Masataka Imura, Kenji Watanabe, Takashi Taniguchi, Takashi Uchihashi, Yamaguchi Takahide
Summary: This study demonstrates that wide-bandgap heterojunction field-effect transistors with a hydrogen-terminated diamond channel and hexagonal boron nitride gate insulator can be created without surface transfer doping. These transistors exhibit low sheet resistance, large ON current, high room-temperature Hall mobility, and normally OFF behavior with a high ON/OFF ratio.
NATURE ELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Fumio Kawamura, Yelim Song, Hidenobu Murata, Hitoshi Tampo, Takehiko Nagai, Takashi Koida, Masataka Imura, Naoomi Yamada
Summary: We demonstrated the correlation between the bandgap of inorganic materials and their effective coordination number through theoretical calculations and experimental validations. The unique relationship between cell volume and bandgap of tin mono-sulphide and germanium mono-sulphide was explained by incorporating the concept of effective coordination number. This theory is applicable to semiconductors with low-symmetry structures. We also experimentally showed that the bandgap of tin mono-sulphide can be tuned by alloying with alkali-earth metals, and n-type conduction can be achieved in tin mono-sulphide based semiconductors.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Applied
Yuichi Ota, Masataka Imura, Ryan G. Banal, Yasuo Koide
Summary: The natural band alignment of BAlN and BGaN alloys was investigated using the atomic solid-state energy scale approach, and it was found that they behave according to the common anion rule. The Schottky barrier height (SBH) was calculated based on the results of band alignment, providing important guidelines for boron nitride and its alloy device design.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Daiki Nishioka, Takashi Tsuchiya, Wataru Namiki, Makoto Takayanagi, Masataka Imura, Yasuo Koide, Tohru Higuchi, Kazuya Terabe
Summary: Physical reservoir computing has gained attention for reducing computational resources, but reported reservoirs have lacked sufficient computing capacity and have been difficult to apply practically. The Li+ electrolyte-based ion-gating reservoir described here offers high performance and can achieve optimal computational capacity in an edge-of-chaos state.
Article
Engineering, Electrical & Electronic
Naoomi Yamada, Mari Mizutani, Kenta Matsuura, Masataka Imura, Hidenobu Murata, Junjun Jia, Fumio Kawamura
Summary: Wurtzite-type MgxZn1-xSnN2 alloys are proposed as promising earth-abundant and tunable band gap semiconductors with the potential to be grown on GaN substrates. These alloys show green-light emissions and can be tuned from 1.5 to 2.3 eV by increasing the composition parameter x. Direct-gap semiconductors with band gaps in the range of 1.8 to 2.5 eV are highly anticipated for the development of green LEDs and high-efficiency tandem solar cells.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Naoomi Yamada, Kenta Matsuura, Masataka Imura, Hidenobu Murata, Fumio Kawamura
Summary: The potential of wurtzite-type MgSnN2 as green emitters in LEDs and absorber material in photovoltaics has been studied, and the electron transport properties can be tailored by varying the cation composition. The Mg1+xSn1-xN2 films with Sn-rich composition exhibited a blue shift in their optical gap, while the intrinsic band gap of MgSnN2 was approximately 2.3 eV.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Crystallography
Jianzheng Hu, Long Yan, Ning Zhou, Yao Chen, Xiaoni Yang, Lianqiao Yang, Shiping Guo
Summary: The effect and mechanism of carrier gas velocity, V/III ratio, and carrier gas velocity match on the growth rate of AlN were investigated in this study. The results showed that the growth rate of AlN initially increased with hydrogen flow rate, reached saturation, and then decreased monotonically. The turning point value depended on the equipment and process. By increasing the MO VM, the growth rate of AlN could be improved, but the uniformity deteriorated due to turbulence and loss of uniform boundary layer. High quality AlN films were successfully grown on nano-patterned sapphire substrates with improved crystalline quality and atomic smooth surfaces.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Tingting Ma, Yang Li, Kangning Sun, Qinglin Cheng, Sen Li
Summary: This study investigates the melting process and nucleation behavior of sodium crystals using molecular dynamics simulation. The results show good agreement between simulated and experimental values for the melting temperature, density, and radial distribution function of sodium. The diffusion coefficient of liquid sodium increases linearly with temperature, and the homogeneous nucleation rate of melting in superheated sodium crystal exponentially increases with temperature. The findings provide theoretical support for applications involving heat and mass transfer in sodium-related systems.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Hisato Nishii, Shintarou Iida, Akira Yamasaki, Takumi Ikenoue, Masao Miyake, Toshiya Doi, Tetsuji Hirato
Summary: Epitaxial V2O3 films were fabricated on sapphire substrates using mist chemical vapor deposition (mist CVD) method, eliminating the need for high vacuum conditions. The films can be grown on sapphire substrates even under atmospheric pressure, with the optimal growth temperature at 823 K. The films grown at 823 K exhibit a metal-insulator transition at approximately 155 K. The film on C-plane sapphire exhibits a lower transition temperature compared to those on R- and A-plane sapphire substrates.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Jani Jesenovec, Kevin Zawilski, Peter Alison, Stephan J. Meschter, Sambit K. Saha, Andrew J. Sepelak, Peter G. Schunemann
Summary: In this study, NiSb needles were successfully formed in InSb by manipulating the growth rate and adding NiSb. These needle structures in InSb can be used to tune the magnetoresistance of devices. Additionally, undoped InSb crystals demonstrated good infrared transmission at low growth rates.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
D. Joseph Daniel, P. Karuppasamy, H. J. Kim
Summary: The 2-amino 4-methyl pyridinium oxalate (2A4MPO) compound was synthesized and its crystal structure, functional groups, thermal stability, electrical properties, and third-order nonlinear optical properties were studied. The results demonstrate that the synthesized crystal has good structural integrity, thermal stability, and potential for third-order nonlinear optical applications.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
C. W. Lan
Summary: The past two decades have witnessed a significant transformation in solar silicon crystal growth, especially in the competition between multi-crystalline silicon (Multi-Si) and mono-crystalline silicon (Mono-Si). The demand for this crucial material has exponentially surged, with silicon solar panels capturing over 95% of the global PV market share. The advancements in crystal growth technology during this period have set historical benchmarks, with the market share shifting from high-performance multi-crystalline silicon (HPM-Si) to CZ silicon.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Peiyao Hao, Lili Zheng, Hui Zhang
Summary: A novel design of argon gas tube for removing impurities during silicon ingot growth was developed, and numerical simulations showed that it can effectively extract SiO.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Geetika Sahu, Chanchal Chakraborty, Subhadeep Roy, Souri Banerjee
Summary: This article discusses the novel fractal nature of hydrothermally synthesized MoS2 QDs. By adjusting the reaction time, the study found that the average size of QDs increases and then decreases with longer reaction times. STEM images indicate that shorter reaction times lead to sheet formation, while extended reaction times cause sheets to fragment into QDs.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Pengjian Lu, Wei Huang, Junjun Wang, Haitao Yang, Shiyue Guo, Bin Li, Ting Wang, Chitengfei Zhang, Rong Tu, Song Zhang
Summary: A systematic study on the tetramethylsilane-hydorgen (TMS-H-2) system for the deposition of pure single-crystal SiC by high-temperature chemical vapor deposition (HTCVD) method is conducted. The study investigates the effect of temperature, pressure, and H-2:TMS ratio on the deposition conditions and provides a theoretical basis and guidance for improving the quality and cost of industrial production of single-crystal SiC.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Xinyu Jiang, Liangliang Liu, Yanqing Liu, Yan Wang, Zhaoping Hou
Summary: Investigation on the preparation of anisometric templated textured high entropy or multi-element doped ferroelectric ceramics was conducted using A-site disordered niobate microcrystals. The effects of process parameters on the morphology and chemical composition were studied, and the photocatalytic properties of the microcrystals were evaluated.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Mobashsara Tabassum, Md. Ashraful Alam, Sabrina Mostofa, Raton Kumar Bishwas, Debasish Sarkar, Shirin Akter Jahan
Summary: In this study, high crystallinity copper nanoparticles were synthesized by altering the reaction medium at low temperatures. The results show that changing the reaction medium can reduce the surface energy of precursors and promote the formation of highly crystalline copper nanoparticles.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Ivan Bodnar, Vitaly V. Khoroshko, Veronika A. Yashchuk, Valery F. Gremenok, Mohsin Kazi, Mayeen U. Khandaker, Tatiana I. Zubar, Daria I. Tishkevich, Alex Trukhanov, Sergei Trukhanov
Summary: This work presents the production of single crystals of Cu2ZnGeSe4, a semiconducting quaternary compound, using a gas chemical method with iodine as a transporter. The phase state, crystal structure, and lattice constants of the synthesized samples were refined and determined. The band gap of Cu2ZnGeSe4 was calculated using transmission spectrum and it was found that the band gap increases by 12% with decreasing temperature in the range of 20-300 K.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Timur Malin, Igor Osinnykh, Vladimir Mansurov, Dmitriy Protasov, Sergey Ponomarev, Denis Milakhin, Konstantin Zhuravlev
Summary: The effect of growth temperature on the buffer leakage currents of GaN-on-Si layers was investigated. It was found that higher growth temperature results in lower leakage currents. The defects in GaN layers grown at different temperatures were studied using photoluminescence technique, and a correlation between leakage currents, structural perfection, and donor concentration in GaN-on-Si layers was established. It was also observed that reduced growth temperature leads to the formation of inversion domains.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Thi-Hoai-Thu Nguyen, Jyh-Chen Chen
Summary: The effect of heater power control on heat, flow, and oxygen transport for CCz crystal growth was studied. Shorter upper side heater design could improve crystal quality and growth, but with higher power consumption.
JOURNAL OF CRYSTAL GROWTH
(2024)
Article
Crystallography
Peter Rudolph
Summary: This article presents an overview of selected contributions to the development of crystal growth technology by the Laudise Prize awardee 2023. It discusses various aspects such as shaped crystal growth, the correlation between melt structure and crystal quality, control of intrinsic defects and inclusions, prevention of dislocation cell patterns, and melt growth experiments under a travelling magnetic field.
JOURNAL OF CRYSTAL GROWTH
(2024)
