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The XeCI* excimer laser is a well-established system tool for many applications. During operation, highly volatile chlorides are often formed, which leads to enhanced electrode erosion and reduced lifetime. Therefore, special attention should be paid to the rate of erosion of all electrode materials that are used in chlorine based excimer lasers. In our work, we came to the result that the chemical behavior of the electrode material is much more important than the classical electrode parameters erosion rate and work function. To separate the erosion rate into a chemical and physical part, we used a nickel electrode as anode (almost no wear) and cathode (low wear compared to tungsten). We concluded that nickel as an electrode material is still the best material in our laser design. [ABSTRACT FROM AUTHOR]

We report an experimental study of an electron cyclotron wave resonance (ECWR) plasma source. The dimensions of the source are considerably larger than in similar experiments. The excitation frequency is 27.12 MHz, the working gas is argon at very low pressures below 0.13 Pa. Spectroscopic data connected with a global model yield electron temperature $T_{\mathrm{ e}}$ , electron number density $n_{\mathrm{ e}}$ , population of the metastable state $n_{\mathrm{ m}}$. The pressure dependencies of these quantities are discussed. Starting from $T_{\mathrm{ e}}\sim 5$ eV at pressure $p=0.13$ Pa the temperature grows as the pressure goes down until the discharge extinguishes at ${\sim }0.6\times 10^{-2}$ Pa. It becomes in the meantime so high that the emission spectra feature strong Ar(II) lines in the region 400–500 nm. At $p=0.13$ Pa and power 300 W the electron density on the axis is about $4\times 10^{10}~{\mathrm{ cm}}^{-3}$ and falls down due to the increase in $T_{\mathrm{ e}}$ as the pressure drops. The discharge was also electrically characterized to determine the plasma impedance $Z$. The impedance and the plasma resistance ${\mathrm{ Re}}(Z)$ are presented as functions of the static magnetic field $B_{\mathrm{ 0}}$. The distribution of power losses are also shown as $B_{\mathrm{ 0}}$ -dependencies. [ABSTRACT FROM AUTHOR]