[Table of Contents]

Plasma and Fusion Research

Volume 6, 2401145 (2011)

Regular Articles

Modeling of Atomic Processes of Multiple Charged Ions in Plasmas and Its Application to the Study of EUV Light Sources
Akira SASAKI, Katsunobu NISHIHARA1), Atsushi SUNAHARA2), Hiroyuki FURUKAWA2), Takeshi NISHIKAWA3) and Fumihiro KOIKE4)
Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kizugawa 619-0215, Japan
Institute of Laser Engineering, Osaka University, Suita 565-0871, Japan
Institute for Laser Technology, Osaka 550-0004, Japan
Department of Electrical and Electronic Engineering, Okayama University, Okayama 700-8530, Japan
Physics Laboratory, School of Medicine, Kitasato University, Sagamihara 228-8555, Japan
(Received 21 December 2010 / Accepted 21 March 2011 / Published 2 December 2011)


Atomic processes of multiple-charged ions of high-Z elements from tin to dysprosium are investigated for their application to light sources for extreme-ultra-violet (EUV) lithography. Modeling of these ions in plasmas, including tungsten, which is being considered for use as a divertor and wall material in the fusion devices, is discussed. Atomic spectra become very complex in the case of low-charged ions below Pd-like ions, which calls for a new atomic code for calculating the energy levels and rate coefficients of collisional and radiative processes. The collisional radiative model is validated through code comparison workshop activities. An alternative method for investigating the formation of the non-uniform structure of the plasmas is also presented.


atomic process, radiative transfer, EUV, lithography

DOI: 10.1585/pfr.6.2401145


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This paper may be cited as follows:

Akira SASAKI, Katsunobu NISHIHARA, Atsushi SUNAHARA, Hiroyuki FURUKAWA, Takeshi NISHIKAWA and Fumihiro KOIKE, Plasma Fusion Res. 6, 2401145 (2011).