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Improved performance and specific results are reported for several test and prototype extreme ultraviolet (EUV) light sources developed for next-generation lithography. High repetition rate and high-power CO2laser-produced plasma sources operating on tin droplet targets are described. Details of laser architecture, source chambers and system operation are given. Stable output power, efficient light collection, and clean EUV transmission could be achieved for hours of operation. We review progress during integration of light sources with collector mirrors reaching EUV power levels at intermediate focus of 60 Wand 45 W, respectively, with duty cycles of 25 and 40. Far-field EUV images of the collected light were recorded to monitor the source output performance during extended tests of collector longevity and debris protection with system operation time exceeding 50 h. Development results on EUV spectra, out-of-band (OOB) radiation, and ion debris obtained with dedicated metrology setups are also described. Angle-resolved measurements with ion energy analyzer and Faraday cups reveal the contributions of individual ion charge states in related spectra. Our laser-produced EUV light source technology has now reached a level of maturity in full integration where prototype sources can be delivered and pilot line introduction can be prepared. [ABSTRACT FROM AUTHOR]