Laser-produced plasma sources

Yashiro, J. Lin, I. Matsushima, K. Komiyama, D. Lee, K. Nishigori, and H. Yokota, Use of tin as a plasma source material for high conversion efficiency, Proc. SPIE 5037, 147 155 (2003). 

Formenkov, R. Olivier, and D. Birx, Development of an EUV (13.5 nm) light source employing a dense plasma focus in lithium vapor, Proc. SPIE 3997, 136 156 (2000). 

Due to their isotropic radiation, LPP sources allow for the use of normal incident collectors thus, higher collection efficiency can be achieved with LLP sources as opposed to DPP sources, which tend to be directional. Because LPP sources do not require electrodes, there is no concern about electrode debris being generated from them. In addition, LLP sources have potential for easier and better thermal management than DPP sources because the plasma they generate is isolated from the collection optics, which is designed to capture the emission from the plasma and relay it to the intermediate focus from where it is relayed to the exposure tool. 

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The two main sources used in commercial EUV lithographic exposure tools comprise laser-produced plasma sources and discharge-produced plasma sources. ... 

Figure 14.10 Schematic of an EUV laser-produced plasma source.

R.J. Rosner, R. Feder, A. Ng, F. Adams, P. Celliers, R.J. Speen Nondestructive single-shot soft X-ray lithography and contact microscopy using a laser-produced plasma source. Appl. Spectr. 26, 4313 (1987)... 

W.T. Silfvast, J.J. Macklin, O.R. Wood II High-gain inner-shell photoionization laser in Cd vapor pumped by soft X-ray radiation from a laser produced plasma source. Opt. Lett. 8, 551 (1983)... 

Utilization of data obtained from various plasma sources (e.g. beam-foil, tokamak and laser-produced plasma [287]) enabled the identification with high accuracy of the lines of highly ionized atoms in solar spectra. A special commision No 14 on Atomic and Molecular Data of the International Astronomical Union coordinates the activity on systematization of spectroscopic data, informs the astrophysics community on new developments and provides assessments and recommendations. It also provides reports which highlight these new developments and list all important recent literature references on atomic spectra and wavelength standards, energy level analyses, line classifications, compilations of laboratory data, databases and bibliographies. 

Rousse A, Audbert P, Geindre JP, Fallies F, Gauthier JC, Mysyrowicz A, Grillon G, Antonetti A (1994) Efficient Ka X-ray source from femtosecond laser-produced plasmas. Phys Rev E 50 2200-2207... 

Aside from the first instant of the interaction of the laser with the matter, the X-ray radiation self-emitted from laser-produced plasmas provides an efficient diagnostic of processes that occur within such plasmas. Over the past ten years, the advent of short-duration laser systems and the progress made in the development of short-pulse X-ray sources have led to such systems being applied to multidisciplinary fields in order to probe matter. 

PMMA) was employed. In addition, atomic force microscopy is used for a more quantitative read-out of the PMMA. Since it is a two-step process - an image formation step on the photoresist followed by a magnification of the miniature contact print formed on the resist - it is difficult to use in the study of dynamic processes. The use of flash sources such as X-ray lasers or laser-produced plasmas in addition to the use of synchrotron radiation sources increased the activity of X-ray contact imaging, allowing the capture of the image on a nanosecond time scale. 

The EXAFS experiment simply involves measuring the absorption spectrum in the vicinity of the absorption edge for the chosen element. This, of course, is easier said than done. A high-intensity, tunable X-ray source is required, and in practice almost aU experiments use synchrotron radiation, which gives useful spectra for solids, liquids or concentrated solutions in a few minutes. The K edges of elements down to about phosphorus or sulfur can be smdied by this method, and typically spectroscopy at the L edges is used for elements heavier than indium (Z = 49). For lighter elements, down to carbon, a laser-produced plasma can... 

C.L. Gordon III, G.Y. Yin, B.E. Lemoff, P.E. Bell, G.P.J. Barty Timegated imaging with an ultrashort-pulse laser-produced-plasma X-ray source. Opt. Lett. 20, 1056 (1995)... 

C. Tillman, G. Grafstrom, A.-Ch. Jonsson, B.-A. Jdnsson, I. Mercer, S. Mattson, S.-E. Strandh, S. Svanberg Survival of mammalian cells exposed to ultrahigh dose rates from a laser-produced plasma X-ray source. Radiology 213, 860 (1999)... 

These include sources such as laser produced plasmas, tokamak plasmas, pinch plasmas, solar flares, stellar X-ray emitters, etc. In such plasmas, the electron temperature (corresponding to a Maxwellian velocity distribution) can be a few hundreds of eV to several keV. On collision with plasma ions these energetic electrons undergo acceleration/deceleration and thereby emit Bremsstrahlung radiation. Electron-electron collisions do not emit any net radiation as the two colliding electrons undergo exactly equal and opposite accelerations. The radiation emitted by the two electrons is therefore equal in magnitude and opposite in phase. Hence, there is no net radiation emitted. 

The resonance line 4s Sq—4s5p P, of this sequence was first identified in spark spectra [1] and the line list derived from the same observations was used to discover some transitions from 4s5d and 4s5s to 4s4p [2]. In the meantime, the resonance line 4s Sq—4s4p P had been identified in laser-produced plasmas [3]. The same kind of light source was... 

When mass spectrometry was first used as a routine analytical tool, El was the only commercial ion source. As needs have increased, more ionization methods have appeared. Many different types of ionization source have been described, and several of these have been produced commercially. The present situation is such that there is now only a limited range of ion sources. For vacuum ion sources, El is still widely used, frequently in conjunction with Cl. For atmospheric pressure ion sources, the most frequently used are ES, APCI, MALDI (lasers), and plasma torches. 

Lasers act as sources and sometimes as amplifiers of coherent k—uv radiation. Excitation in lasers is provided by external particle or photon pump sources. The high energy densities requked to create inverted populations often involve plasma formation. Certain plasmas, eg, cadmium, are produced by small electric discharges, which act as laser sources and amplifiers (77). Efforts that were dkected to the improvement of the energy conversion efficiencies at longer wavelengths and the demonstration of an x-ray laser in plasma media were successful (78). 

This fact has been used to measure electron and ion temperatures in a theta-pinch plasma 28i), and a dense plasma (/tg = 10 cm ) produced in a carbon arc 282). Both experiments employed pulsed ruby lasers as light sources. 

The (TiN) + clusters produced by a laser-induced plasma reactor source were investigated by means of time-of-flight mass spectrometry. The mass spectral abundance indicates that the clusters have cubic structures resembling subunits of the fee lattice of TiN. The primary stoichiometries observed are (TiN) + (n = 1-126), except for Ti N , (n = 14, 63) (36). 

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