Fundamental atomic process in source development for beyond EUV Lithography and other applications

Development of EUV/SXR sources with emission at wavelengths less than 10 nm has moved from being a subject of interest for next generation semiconductor lithography to one for both nanoscale surface patterning and imaging. Systematic calculations for UTA positions were performed for elements with atomic number Z = 49-92, with the help of both laser produced plasmas (LPPS) and Large Helical Device (LHD) experimental measured spectra it was found that the peak such UTAs in optically thin plasmas in the extreme ultraviolet region follows a quasi-Moseley's law. We carried out a detailed calculation on dielectronic recombination rate coefficients of Ne-, Rh-, Pd- and Ag-like W. Excellent agreement has been found for Ne-like W while a large discrepancy was found for Pd-like W, which implies that more ab initio calculations and experimental measurements are badly needed. (author)