Enhancing conversion efficiency of laser-produced tin plasma EUV light sources using thulium lasers
Chun-Tse Wu1*, Yao-Li Liu2, Po-Yen Lai1, Shih-Hung Chen1
1Physics Department, National Central University, Taoyuan, Taiwan
2Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan, Taiwan
* Presenter:Chun-Tse Wu, email:109222032@cc.ncu.edu.tw
High-power laser-produced tin plasma EUV (LPP-EUV) light sources have become essential tools for high volume semiconductor manufacturing. Improving the conversion efficiency (CE) of LPP-EUV light sources is always crucial for reducing cost and energy consumption. A one-dimensional simulation framework has been developed to investigate the CE of LPP-EUV light sources [1]. The simulation framework self-consistently models the laser-plasma interactions [2], energy level transition of tin ions, and EUV radiation transport with the quasi-equilibrium assumption for dealing with the nature of multiple time scales in LPP-EUV light sources. The simulation framework has been benchmarked using experimental results and is applied to study LPP-EUV light sources using thulium lasers [3]. The new configuration of LPP-EUV light sources can considerably reduce energy consumption due to thulium lasers' high electricity-to-optical (EO) efficiency. Additionally, the CE of the new LPP-EUV light sources using a longer laser wavelength is higher than that using Nd:YAG lasers. These reasons motivate the following research works to increase CE by optimally adjusting the laser pulse length and intensity of thulium lasers.

[1] Po-Yen Lai. "Numerical study of laser-driven plasma spectroscopy and kinetic behavior of a collisional plasma: For application of a laser-produced Sn plasma extreme ultraviolet light source." PhD Thesis. National Central University, 2016.
[2] CHRISTIANSEN, J. P.; ASHBY, D. E. T. F.; ROBERTS, K. V. MEDUSA a one-dimensional laser fusion code. Computer Physics Communications, 1974, 7.5: 271-287.
[3] Behnke, L., Schupp, R., Bouza, Z., Bayraktar, M., Mazzotta, Z., Meijer, R., ... & Versolato, O. O., “Extreme ultraviolet light from a tin plasma driven by a 2-µm-wavelength laser,” Optics express, 29(3), 4475-4487. (2021).


Keywords: Laser-Produced Plasma, Extreme Ultraviolet, Fluid Simulation