Optimizing EUV Source Efficiency With Radiation-Hydrodynamic Simulations (U. Of Osaka et al.)

Researchers from The University of Osaka, National Institute for Fusion Science, National Institutes for Quantum Science and Technology, and Osaka Metropolitan University, et al. have published “Optimization of EUV output by experimentally validated radiation-hydrodynamic simulations across a broad laser parameter space”.

Abstract

“Practical requirements such as improving wall-plug efficiency and reducing system footprint have become increasingly important with the introduction of extreme ultraviolet (EUV) lithography into high-volume semiconductor manufacturing. These demands motivate the development of solid-state mid-infrared lasers as alternatives to current CO2 lasers. Systematic exploration of laser-to-EUV conversion efficiency (EUV-CE) over a broad parameter space is essential when altering the drive laser’s wavelength, because the EUV-CE depends on the laser parameters in a complex manner. In this work, we performed a large-scale grid search of more than 140,000 parameter combinations for laser-produced tin plasma EUV sources using the radiation-hydrodynamics code STAR-1D, which is validated against EUV source experiments. The systematic wavelength dependence of the optimum pulse width and target size is governed by the requirement to simultaneously achieve the electron temperature and density optimal for EUV emission, maintain efficient laser absorption, and suppress EUV self-absorption. The resulting CE map predicts a global maximum of 5.63% at 5.5 µm. For the practically relevant 2 µm solid-state driver, a maximum CE of 4.64% is obtained, in good agreement with recent experimental results. Multiple operating points are identified over a broad range of pulse parameters, providing guidance for 2 µm-driven EUV source development.”

Find the technical paper here. June 2026.

Tanaka, Nozomi, Yu Yamamoto, Akira Sasaki, Katsunobu Nishihara, Atsushi Sunahara, Tomoyuki Johzaki, Yuji Takagi, Kentaro Tomita, Shinsuke Fujioka, and Masashi Yoshimura. “Optimization of EUV output by experimentally validated radiation-hydrodynamic simulations across a broad laser parameter space.” arXiv:2606.05948, June 2026. https://doi.org/10.48550/arXiv.2606.05948.