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We use a Dense Plasma Focus (DPF) device NX2, with improved insulator, electrode, and switching configuration, and with Argon filling to concentrate the main part of its radiation near 4 A. In this case it can be used as a source for different aims in micro-lithography. One evident goal here is to increase spatial resolution of the method with the help of a source having a shorter wavelength in comparison with widely used Ne gas filling of DPF. But in particular it can be implemented in micro machining when it emits enough harder X-rays with Argon as a working gas, but it is attainable if plasma can reach Tpl=1 keV at the pinching phase. There are at least three possible ways to get the above temperature and high X-ray yield around wavelength of 4 A. One is to use a mixture of light gas (ultimately deuterium) with argon to produce hot spots by plasma necking. Another one is to increase CS velocity in pure argon. The third one is to use a mixture of heavy gas (e.g. krypton) with argon to produce separation of gases at the shock wave front of a DPF current sheath and subsequently to compress argon by a heavy shell. In the last two cases longer electrodes and lower initial pressure are needed for DPF-bank matching. Using a pinhole with a CCD matrix and a pair of folded by different foils pin diodes in all three methods we have successfully reached a reasonable yield in the above-mentioned spectral range. It was respectively about 0.4J 1.0J and 10.0J. Within all three modes of the DPF operation it was possible clearly to find a distinction between three characteristic regimes: a pinch regime, a hotspot regime, and a runaway regime.
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