The 29th International Conference on Amorphous and Nano-crystalline Semiconductors-Keisuke Ohdaira (Topic 2)

Keisuke Ohdaira

Silicon Thin Film

Japan Advanced Institute of Science and Technology

1-1 Asahidai, Nomi, Ishikawa, Japan

Email: ohdaira@jaist.ac.jp

Biography

Dr. Keisuke Ohdaira is a Professor in the School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST). He received his PhD from in the Department of Applied Physics, School of Engineering, University of Tokyo under Prof. Yasuhiro Shiraki in 2004. He then moved to Tohoku University and worked as a post-doctoral researcher between 2004 and 2005. On September in 2005, he joined the School of Materials Science at the Japan Advanced Institute of Science and Technology as an Assistant Professor. He was promoted to an Associate Professor at the same institute in 2012 and to a Professor in 2018. He received the best paper award of the 27th photovoltaic science and engineering conference (PVSEC-27) in 2017.

Current research topics are related to formation of polycrystalline silicon films by flash lamp annealing and its application to thin-film solar cells, silicon-based solar cells including surface passivation of crystalline silicon using thin films formed by catalytic chemical vapor deposition (Cat-CVD), potential-induced degradation (PID) of n-type crystalline silicon photovoltaic modules, utilization of Cat-CVD silicon-based films for perovskite and perovskite/silicon tandem solar cells, and the development of novel encapsulant-free photovoltaic modules.

Abstract for Presentation

Formation of polycrystalline silicon films on glass substrates by flash lamp annealing of amorphous silicon films

Polycrystalline Si (poly-Si) films on glass substrates are expected for the usage in low-cost thin-film solar cells. We have thus far demonstrated that micrometer-order-thick precursor amorphous Si (a-Si) films can be crystallized by flash lamp annealing (FLA), millisecond-order annealing using pulse light from a Xe lamp.[1] Figure 1 shows a photograph of our FLA system. The crystallization of a-Si films takes place through lateral explosive crystallization (EC), continuous crystallization driven by the release of latent heat through phase transition from metastable a-Si to stable crystalline Si and its thermal diffusion to surrounding a-Si.[2] Recently, we have demonstrated that the EC of a-Si films induced by FLA can occur also on textured glass substrates.[3] The textured surface of glass substrates realizes the crystallization of a-Si films without film peeling even with no metal adhesion layer such as chromium. The textured surface of glass substrate may also enhance light trapping particularly when the poly-Si films are used for superstrate-type solar cells. In the presentation, I will review our previous achievements for the EC of a-Si films by FLA and also show our recent results for the formation of poly-Si films on textured glass substrates.

Figure 1. Photograph of the FLA system.

References

[1] K. Ohdaira, Y. Endo, T. Fujiwara, S. Nishizaki, and H. Matsumura, Jpn. J. Appl. Phys. 2007, 46, 7603.

[2] K. Ohdaira, T. Fujiwara, Y. Endo, S. Nishizaki, and H. Matsumura, J. Appl. Phys. 2009, 106, 044907.

[3] Z. Wang, H. T. C. Tu, and K. Ohdaira, Jpn. J. Appl. Phys. 2022, 61, SB1019.