Gallium–tin alloys as a low melting point liquid metal for repetition-pulse-laser-induced high energy density state toward compact pulse EUV sources

Abstract

Here, we show the easy-handling of a liquid gallium–tin alloy (Ga : Sn) as a laser target source for 13.5 nm light generation. The alloys have ∼30 °C freezing points according to a differential scanning calorimetry cooling process. A Nd:YAG laser (1064 nm, 1 ns, 7.1 × 10¹⁰ W cm⁻²) ablated the alloys, obtaining a similar extreme ultraviolet emission intensity to Sn despite a small quantity of Sn. Finally, we demonstrate a liquid metal alloy jet and droplets using a plastic nozzle for high-repetition target supply.