Zobrazeno 1 - 10
of 123
pro vyhledávání: '"Takeyoshi Onuma"'
Autor:
Lena N. Majer, Tolga Acartürk, Peter A. van Aken, Wolfgang Braun, Luca Camuti, Johan Eckl-Haese, Jochen Mannhart, Takeyoshi Onuma, Ksenia S. Rabinovich, Darrell G. Schlom, Sander Smink, Ulrich Starke, Jacob Steele, Patrick Vogt, Hongguang Wang, Felix V. E. Hensling
Publikováno v:
APL Materials, Vol 12, Iss 9, Pp 091112-091112-11 (2024)
Sapphire is a technologically highly relevant material, but it poses many challenges when performing epitaxial thin-film deposition. We have identified and applied the conditions for adsorption-controlled homoepitaxial growth of c-plane sapphire. The
Externí odkaz:
https://doaj.org/article/772d23a5e0ab4c3e9c68fb024f86b584
Autor:
Jacob Steele, Kathy Azizie, Naomi Pieczulewski, Yunjo Kim, Shin Mou, Thaddeus J. Asel, Adam T. Neal, Debdeep Jena, Huili G. Xing, David A. Muller, Takeyoshi Onuma, Darrell G. Schlom
Publikováno v:
APL Materials, Vol 12, Iss 4, Pp 041113-041113-12 (2024)
We report the use of suboxide molecular-beam epitaxy (S-MBE) to grow α-(AlxGa1−x)2O3 films on (110) sapphire substrates over the 0 < x < 0.95 range of aluminum content. In S-MBE, 99.98% of the gallium-containing molecular beam arrives at the subst
Externí odkaz:
https://doaj.org/article/8e5716fe4ea840c88b93a1a3e8d79dc3
Publikováno v:
AIP Advances, Vol 13, Iss 5, Pp 055304-055304-7 (2023)
We have calculated formation enthalpies, bandgaps, and natural band alignment for MgO1−xSx alloys by first-principles calculation based on density functional theory. The calculated formation enthalpies show that the MgO1−xSx alloys exhibit a larg
Externí odkaz:
https://doaj.org/article/67da2f4b229a4fd59635f6b71af3dcc4
Autor:
Masahiko Nakanishi, Man Hoi Wong, Tomohiro Yamaguchi, Tohru Honda, Masataka Higashiwaki, Takeyoshi Onuma
Publikováno v:
AIP Advances, Vol 11, Iss 3, Pp 035237-035237-5 (2021)
Acceptor impurity doping is recognized as a functional tool to extend the capabilities and applications of β-Ga2O3. The effect of thermal annealing on photoexcited carriers was characterized by measuring the photocurrent spectra of nitrogen (N)-ion-
Externí odkaz:
https://doaj.org/article/19e4ebf9e8d44b4c8b5e0faa33025da9
Autor:
Naoki Ogawa, Hiroki Nagai, Yukihiro Kudoh, Takeyoshi Onuma, Taichi Murayama, Akinobu Nojima, Mitsunobu Sato
Publikováno v:
Nanomaterials, Vol 11, Iss 12, p 3404 (2021)
A single-walled carbon nanotube (SWCNT)-silica composite thin film on a quartz glass was formed by ultraviolet irradiation (20–40 °C) onto a spin-coated precursor film. With 7.4 mass% SWCNTs, the electrical resistivity reached 7.7 × 10−3 Ω·cm
Externí odkaz:
https://doaj.org/article/dd7cd1269b024f939ac9919543c8dedb
Autor:
Masatomo Sumiya, Kiyotaka Fukuda, Hideo Iwai, Tomohiro Yamaguchi, Takeyoshi Onuma, Tohru Honda
Publikováno v:
AIP Advances, Vol 8, Iss 11, Pp 115225-115225-7 (2018)
We characterize the behavior caused by thermal annealing for C, O, Si and Mg ions implanted in GaN films by photothermal deflection spectroscopy (PDS) with respect to structural disorder and defect levels related to yellow luminescence. Although the
Externí odkaz:
https://doaj.org/article/3ce3190185e24782acf3695b516a3e19
Autor:
Haruka Matsuura, Takeyoshi Onuma, Masatomo Sumiya, Tomohiro Yamaguchi, Bing Ren, Meiyong Liao, Tohru Honda, Liwen Sang
Publikováno v:
Applied Sciences, Vol 9, Iss 9, p 1746 (2019)
The investigation of the III-V nitride-based driving circuits is in demand for the development of GaN-based power electronic devices. In this work, we aim to grow high-quality InGaN/GaN heterojunctions on the n-channel AlGaN/GaN-on-Si high electron m
Externí odkaz:
https://doaj.org/article/ffc5d5eec7734a5ebc282673f4b084ec
Publikováno v:
Journal of the Society of Materials Science, Japan. 70:727-731
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f4a5f324f6807f96d99405b566f0c6f7
https://doi.org/10.2472/jsms.70.727
https://doi.org/10.2472/jsms.70.727
Autor:
Akito Taguchi, Takumi Yamamoto, Kentaro Kaneko, Ken Goto, Takeyoshi Onuma, Tohru Honda, Yoshinao Kumagai, Shizuo Fujita, Tomohiro Yamaguchi
Publikováno v:
Japanese Journal of Applied Physics. 62:SF1023
The heteroepitaxial growth of In2O3 on a (0001) α-Al2O3 substrate was carried out using the mist chemical vapor deposition method. The concentrations of In2O3 powder in the source precursor solution varied between 0.025 and 0.250 mol l−1. An incre
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f3d480d47c0ffa272bdc61e80104ca6c
https://doi.org/10.35848/1347-4065/acbeba
https://doi.org/10.35848/1347-4065/acbeba
Autor:
Masatomo Sumiya, Shigenori Ueda, Kiyotaka Fukuda, Shinya Takashima, Akira Uedono, Tomohiro Yamaguchi, Tohru Honda, Takeyoshi Onuma
Publikováno v:
Journal of Crystal Growth. 511:15-18
Both structure of the valence band maximum (VBM) and deep-level defects for box-profile Mg-ion implanted (4 × 1019 cm−3) GaN samples are characterized by photothermal deflection spectroscopy (PDS). Compared with the results evaluated by positron a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3fe34e46c88e922324e540cac21fc689
https://doi.org/10.1016/j.jcrysgro.2019.01.021
https://doi.org/10.1016/j.jcrysgro.2019.01.021