Invited Speaker

Dr. Tetsuya Yamamoto

Dr. Tetsuya Yamamoto

Professor, Materials Design Center, Research Institute
Kochi University of Technology, Japan
Speech Title: Materials Design of Highly Transparent Conductive Oxides with Thicknesses Ranging from 2 to 2000 nm for Wide Applications

Abstract: We propose the materials design of smart oxide films with thicknesses ranging from 2 to 2000 nm for wide applications. We have succeeded in the 100-nm-thick high Hall mobility (µH) Ce-doped hydrogenated In2O3 films for use as electrodes in photovoltaic solar cells, that have been commercial. In order to develop new type of 2D materials, we very recently reported high µH W-doped In2O3 polycrystalline films with thicknesses ranging from 5 to 10 nm. For Ga-doped ZnO (GZO) films, we have found that a decrease in thicknesses of 50 nm or less causes a reduction of Young modulus, i.e., such thin films show the flexibility. This research produces polymer substrates with GZO films. On the other hand, thick some micron meter-thick GZO films show magnetic shielding characteristics. We have been developing the unique deposition apparatus; reactive plasma deposition with dc arc discharge (RPD) through the academic-industrial collaboration that has been already commercial. The typically film-deposition rates is 200 nm/min. The RPD provides smart oxide films deposited on the substrates with a large size of 1m×1m. In this presentation, we show smart materials design together with the above business.

Keywords: Highly transparent conductive oxides, 2D, flexibility, carrier transport, reactive plasma deposition.

References:
Eiji Kobayashi, Yoshimi Watabe, Tetsuya Yamamoto, Yoichi Yamada,Sol. Energy Mater. Sol. Cells 149 (2016) 85–90;
Yutaka Furubayashi, Makoto Maehara, Tetsuya Yamamoto, Nanoscale Res. Lett. 14 (2019) 20;
Tetsuya Yamamoto, Rajasekaran Palani, Hisashi Kitami, Hisao Makino, JSAP Rev. (2024) 240404-1-240404-5.

Acknowledgements: We have been continuing a joint research and development with Sumitomo Heavy Industries, Ltd. We would like to express our deepest gratitude to all involved.


Biography: Tetsuya YAMAMOTO is a full professor at Kochi University of Technology (Japan) since 2001. He received Ph.D. degree in Theoretical Physics (OSAKA University, Japan, 1997). He has been a Professor of graduate school, and also Director, Materials Design Center, Research Institute of the same University, from 1999 – Present (24 years). His major research concerns materials design, developments of film-deposition apparatus, and device developments based on oxide semiconductors. Many products together with patents thorough co-developed with industries including several national projects have been already commercial. He has been serving as the general chair and symposium organizers of numerous international conferences. He won the prize by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) for his work on ZnO-based TCO films for use in Liquid Crystal Display (LCD)-TV in 2011.