OHDAIRA, Keisuke Professor
School of Materials Science,Energy and Environment Area
◆Degrees
Ph.D. from The University of Tokyo
◆Specialties
Solar cell, Semiconductor
◆Research Keywords
Catalytic chemical vapor deposition
◆Research Interests
Formation of high-quality poly-Si films by flash lamp annealing and their application to high-efficiency solar cells
We investigate on formation of high-quality poly-Si on glass substrates by flash lamp annealing, with millisecond duration, of Cat-CVD a-Si films and fabrication of solar cells using the poly-Si films. 備考
Application of Cat-CVD to the fabrication process of c-Si solar cells
Cat-CVD (catalytic chemical vapor deposition), in which gas molecules are decomposed on heated catalyzing wire by catarytic reaction, can deposit high-quality passivation films to reduce the recombination of photo-generated carriers on crystalline Si surface. We develop high-quality Cat-CVD passivation films for crystalline Si solar cells. We also investigate a novel doping method using a Cat-CVD system.
Potential-induced degradation for n-type crystalline silicon photovoltaic modules
The performance degradation of photovoltaic modules originating from a large voltage between an Al frame and cells (potential-induced degradation: PID) has been a significant problem in large-scale PV power plants. We investigate the mechanism of PID and its suppression particularly for n-type c-Si PV modules, which have higher performances than p-type ones and are thus expected to be widely utilized in the future.

■Publications

◆Published Papers
Fabrication of silicon heterojunction solar cells with a boron-doped a-Si:H layer formed by catalytic impurity doping
K. Akiyama and K. Ohdaira
AIP Advances, 9, 115013-1-115013-6, 2019/11
Influence of backsheet materials on potential-induced degradation in n-type crystalline-silicon photovoltaic cell modules
S. Yamaguchi, C. Yamamoto, A. Masuda, and K. Ohdaira
Jpn. J. Appl. Phys., 58, 120901-1-120901-3, 2019/11
Conversion of the conduction type of a catalytic-chemical-vapor-deposited p-type a-Si by PH3 plasma ion implantation
Huynh Thi Cam Tu, K. Koyama, N. Yamaguchi, H. Suzuki, K. Ohdaira, and H. Matsumura
Thin Solid Films , 683, 150-155, 2019/08
Oxygen additive effects on decomposition rate of poly(vinyl phenol)-based polymers using hydrogen radicals produced by a tungsten hot-wire catalyst
M. Yamamoto, S. Nagaoka, K. Ohdaira, H. Umemoto, and H. Horibe
Thin Solid Films, 679, 22-26, 2019/06
Influence of sodium on the potential-induced degradation for n-type crystalline silicon photovoltaic modules
K. Ohdaira, Y. Komatsu, T. Suzuki, S. Yamaguchi, and A. Masuda
Appl. Phys. Express, 12, 064004-1-064004-4, 2019/05
◆Misc
Passivation of crystalline silicon surfaces with ultra-thin silicon nitride films formed by catalytic chemical vapor deposition
H. Song, and K. Ohdaira
Proc. 35th European Photovoltaic Solar Energy Conference and Exhibition, 621-623, 2018
Vacuum deposition of CsPbI3 layers on textured Si for perovskite/Si tandem solar cells
K. Hamada, K. Yonezawa, K. Yamamoto, T. Taima, S. Hayase, N. Ooyagi, Y. Yamamoto, and K. Ohdaira
Extended Abstract of the 2018 International Conference on Solid State Devices and Materials, -, 2018
Crystallization of electron-beam evaporated a-Si films on textured glass substrates by flash lamp annealing
K. Kurata and K. Ohdaira
Extended Abstract of the 2018 International Conference on Solid State Devices and Materials, -, 2018
ITO sputtering damage to silicon heterojunction solar cells with Cat-CVD a-Si films and its recovery
T. Konishi and K. Ohdaira
Proc. 33rd European Photovoltaic Solar Energy Conference and Exhibition, -, 2017
Low-cost fabrication of patterned electrodes in hetero-junction back-contact silicon solar cells by plasma ion-implantation
K. Koyama, K. Ohdaira, and H. Matsumura
Proc. 33rd European Photovoltaic Solar Energy Conference and Exhibition, 2017 , Proc. 33rd European Photovoltaic Solar Energy Conference and Exhibition, 2017 , -, 2017
◆Conference Activities & Talks
Sub-20 Nm thick ferroelectric Hf-Zr-O flims fabricated by solution process for ferroelectric-gate TFT applications
モヒート、 住友 誠明、 羽賀 健一、 大平 圭介、 徳光 永輔
薄膜材料デバイス研究会 第16回研究集会「新時代に向けた薄膜材料のデバイス技術」 , 2019/11/08
Systematic study on potential-induced degradation of n-type crystalline Si photovoltaic modules
K. Ohdaira
The 29th International PV Science and Engineering Conference (PVSEC-29) , 2019/11/04
Tunneling conductivity of ultra-thin SiNx films for TOPCon-like solar cells formed by Cat-CVD
Y. Wen and K. Ohdaira
The 29th International PV Science and Engineering Conference (PVSEC-29) , 2019/11/04
Potential-induced degradation and recovery behaviors of photovoltaic modules with n-type front-emitter crystalline Si cells without SiO2
T. Suzuki, S. Yamaguchi, K. Nakamura, A. Masuda, and K. Ohdaira
The 29th International PV Science and Engineering Conference (PVSEC-29) , 2019/11/04
Fabrication of SHJ solar cells with p-type a-Si films formed from n-a-Si by B Cat-doping
T. Tsurugai and K. Ohdaira
The 29th International PV Science and Engineering Conference (PVSEC-29) , 2019/11/04

■Teaching Experience

Solid State Physics and its Application to Electronics II(E), Advanced Device Physics(E), Mathematics for Condensed Matter Science and Technology

■Contributions to  Society

◆Academic Society Affiliations
The Japan Society of Applied Physics, IEEE, International Conference on Solid State Devices and Materials (SSDM), Active-Matrix Flatpanel Displays and Devices (AM-FPD), International Conference on Hot-Wire Chemical Vapor Deposition (Cat-CVD) Process

■Academic  Awards

・ PVSEC-27 Best Paper Award , PVSEC-27 Technical Program Committee , 2017/11/17
・ 第22回(2007年春季)応用物理学会講演奨励賞 , The Japan Society of Applied Physics , 2007/09/04