Preliminary results from key experiments on sources for EUV lithography

While huge progress has been achieved for EUVL system design and multilayer optics during the last years the decision on the best suited source is still open. In a German basic research cooperation on short-wavelength plasma based sources some key issues also relevant for EUVL are addressed: the comparison of existing sources, investigations on the scalability of source concepts and the demonstration of key features. Preliminary results of investigations on parameters for best conversion efficiency of laser produced plasmas, concepts for high-power lasers and scalability of gas discharge based sources are presented. Comparability of results is assured by calibrated metrology tools which are cross checked with ASML's flying circus.