Plasma and Fusion Research

Volume 3, 043 (2008)

Regular Articles

Optimization of Extreme Ultraviolet Emission from Laser-Produced Tin Plasmas Based on Radiation Hydrodynamics Simulations

Atsushi SUNAHARA, Katsunobu NISHIHARA¹⁾ and Akira SASAKI²⁾

Institute for Laser Technology, 2-6 Yamadaoka Suita Osaka 565-0871, Japan
1): Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka Suita Osaka 565-0871, Japan
2): Advanced Photon Research Institute of Japan Atomic Energy Agency, 8-1 Umemidai Kizugawa Kyoto 619-0215, Japan

(Received 14 April 2008 / Accepted 6 June 2008 / Published 4 August 2008)

Abstract

We investigated the plasma conditions for obtaining highly efficient extreme ultraviolet light from laserproduced tin plasmas for lithography of next generation semiconductors. Based on accurate atomic data tables calculated using the detailed configuration accounting code, we conducted 1-D radiation hydrodynamic simulations to calculate the dynamics of tin plasma and its emission of extreme ultraviolet light. We included the photo-excitation effect in the radiation transport. Our simulation reproduced experimental observations successfully. Using our verified code, we found that a CO2 laser can be useful in obtaining higher conversion efficiencies up to 4%.

Keywords

EUV, lithography, radiation hydrodynamics, conversion efficiency, laser-produced tin plasma

DOI: 10.1585/pfr.3.043

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This paper may be cited as follows:

Atsushi SUNAHARA, Katsunobu NISHIHARA and Akira SASAKI, Plasma Fusion Res. 3, 043 (2008).