Extreme ultraviolet emission from Xe clusters excited by high-intensity lasers

Abstract

The property of extreme ultraviolet (EUV) generation from Xe clusters irradiated with intense lasers was studied. The Xe cluster jet was well characterized by the interferometric method. In order to obtain the adequate irradiation condition for strong EUV generation, EUV spectra were taken with various laser systems. Then, the wavelength, the pulse width, and the pump energy were widely varied. Through this survey, even with the comparatively low-density Xe jet of ⩽5×1018 cm−3 average atomic density, the highest conversion efficiency of over 10% from laser energy to EUV (5–18 nm) was obtained with a subpicosecond KrF laser pulse, where a 4π source was assumed. This EUV source is considered to be attractive as an EUV lithography light source because of its low average atomic density and small Xe cluster.

Efficient extreme ultraviolet emission from xenon-cluster jet targets at high repetition rate laser illumination

“…It is ϳ(3 -4)ϫ10 19 cm Ϫ3 at 30-40 bar 16 and fits to the extrapolated data from Ref. 35. Within this picture the density remains nearly constant in the first 100 ps and decreases slowly in the following 10 ns.…”

“…It is worth noting that the measured efficiency was in the range of the highest values reported in the literature using the Xe cluster or Xe gas target system and laser pulses with moderate intensities. [33][34][35] The influence of laser pulse duration on Xe plasma production and related EUV emission can be discussed in context with the plasma expansion time. 4 Inside the cluster media laser energy can be effectively absorbed if pulses are shorter or comparable to the disassembly time of the clusters.…”

Optimizing conversion efficiency and reducing ion energy in a laser-produced Gd plasma

“…Information on ion time of flight (TOF) signals was recorded to help better understand the effect of pulse duration on ion energy. The effects of pulse duration on CE and EUV generation from other source materials have been previously investigated [9][10][11][12][13]. For example, the maximum CE for neodymium doped yttrium-aluminiumgarnet (Nd:YAG) laser irradiation of Sn targets was obtained using a 2.3 ns pulse by Ando et al.…”

Interaction of intense laser pulses with atomic clusters: Measurements of ion emission, simulations and applications

“…This is comparable with the yields from solid targets. Many experiments have studied the yields and parameter scaling of the X-ray emission with a view to applications [62,56,[63][64][65]. This continues to be an active area of research.…”