Note: Study of extreme ultraviolet and soft x-ray emission of metal targets produced by laser-plasma-interaction

Abstract

Different metal targets were investigated as possible source material for tailored laser-produced plasma-sources. In the wavelength range from 1 to 20 nm, x-ray spectra were collected with a calibrated spectrometer with a resolution of λ/Δλ = 150 at 1 nm up to λ/Δλ = 1100 at 15 nm. Intense line emission features of highly ionized species as well as continuum-like spectra from unresolved transitions are presented. With this knowledge, the optimal target material can be identified for the envisioned application of the source in x-ray spectrometry on the high energy side of the spectra at about 1 keV. This energy is aimed for because 1 keV-radiation is ideally suited for L-shell x-ray spectroscopy with nm-depth resolution.

High average power, highly brilliant laser-produced plasma source for soft X-ray spectroscopy

“…The three pulse durations as well as other target materials 15 can be utilized without high experimental effort. Hence, depending on the envisioned experiment, the energy range of interest can be chosen individually and optimized according to intensity and emission type (continuum-like or intense line emission).…”

“…Both angle of laser incidence and the exit angles were chosen as a compromise between efficient plasma heating and debris minimization. 15,17 The laser entrance window is protected through a thin glass plate from debris, see Figure 1, right. This plate can be changed manually during operation without the necessity of breaking the vacuum.…”

“…This system offers the possibility to use different metals as target material for the plasma production. 15 To ensure a clean surface for each laser shot, the cylinder is rotated and translated during operation with 100 µm distances between each laser shot.…”

“…Both discharge-plasmas 12,13 as well as laser-produced plasmas (LPPs) 8,10,14,15 are already a) Present address: ELI-DC AISBL, 23 Rue Montoyer, 1000 Brussels, Belgium. used in various generation schemes.…”

Grazing-incidence x-ray fluorescence analysis for non-destructive determination of In and Ga depth profiles in Cu(In,Ga)Se2 absorber films

“…The low divergence and well-known intensities of this radiation are ideal for the investigation of the capability of GIXRF, but makes it unsuitable for standard measurements or in-line process control. As X-ray sources, 21,22 multilayer optics 23 and detector technologies 24,25,26 develop rapidly, high X-ray fluorescence count rates on a labscale setup for in-line or other lab-size applications of this method should become feasible. Besides these perspectives, the more elaborate synchrotron-based approach is attractive as reference measurement method, since GIXRF in combination with calibrated instrumentation provides quantitative access to the in-depth distribution of the elements.…”