Hyper Hemispherical Silicon Lens for Laser Terahertz Emission Microscope

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Laser terahertz emission microscope and its application
M. Tonouchi
Published 2015
Materials Science
2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz)
One can observe terahertz (THz) emission upon femtosecond (fs) optical pulse illumination from various materials. Scanning fs laser beam on the materials gives us an image to visualize its dynamic optical response to generate rapid generation of photocurrent. We named the system as laser THz emission microscope (LTEM). In the present work, recent progress of LTEM and its application will be reviewed.

[delmarphotonics]

SPIE Optics and Photonics Conference Presentation, San Diego, CA
Laser terahertz emission microscopy for silicon electronics
21 August 2022 • 10:20 AM - 10:50 AM PDT | Conv. Ctr. Room 16B

Abstract
Authors
Terahertz (THz) emission from the silicon (Si) surface by the femtosecond laser illumination shows a lot of information, known as the THz emission spectroscopy (TES) or the laser-induced THz emission microscope (LTEM), which seems to be the promising method for evaluating the surface/interface properties of Si-based devices, such as Si metal-oxide-semiconductor (Si MOS) structure. To enlarge the application and explore silicon electronics, it is necessary to build a theoretical model, which can accurately and simply describe the relationship between the THz emission amplitude and the external bias voltage on the Si MOS structure. Here, we focus on the THz emission spectrum from the p-type Si MOS structure and discuss the THz emission field under different DC bias conditions. The theoretical model is derived from Poisson’s equation and shows great consistency with the experiment results. Besides that, the flat-band voltage, interface trap states, and photo-Dember effect have been discussed to modify the model.
Presenter
Masayoshi Tonouchi
Osaka Univ. (Japan)
Masayoshi Tonouchi received the B.S. and M.S. and Dr. E. degrees from Osaka University, Japan, in 1983, 1985, and 1988, respectively. From 1988 to 1989 he worked at Osaka University, at Kyushu Institute of Te\chnology, from 1994 to 1996, Communications Research Laboratory, and since then, he was an associate professor at the Research Center for Superconductor Pho-tonics, Osaka University. Since 2000, he is a professor of Osaka University. His current research interests include ultrafast optical and terahertz science in advanced materials and the development and applications of terahertz systems such as the laser terahertz emission microscope. He is an associated Editor: Journal of Applied Physics, American Institute of Physics, since 2015and a fellow of The Japan Society of Applied Physics.