We reported 1st generation Laser-Produced Plasma source system "ETS" device for EUV lithography one year ago 1) . In this paper we update performance status of the 1st generation system. We have improved the system further, maximum burst power is 104W (100kHz, 1 mJ EUV power @ intermediate focus), laser-EUV conversion efficiency is 2.5%. Also continuous operation time is so far up to 8 hours with 5% duty cycle is achieved. We have investigated EUV plasma creation scheme by small experimental device which is facilitated 10Hz operation (maximum). We have proposed double pulse method to create LPP plasma efficiently. This moment we found out 3.3% conversion efficiency operation condition.Based on the engineering data of ETS and small experimental device, now we are developing 2 nd generation HVM source; GL200E. The device consists of the original concepts (1) CO 2 laser driven Sn plasma, (2) Hybrid CO 2 laser system that is combination of high speed (>100kHz) short pulse oscillator and industrial cw-CO 2 , (3) Magnetic mitigation, and (4) Double pulse EUV plasma creation. The preliminary data are introduced in this paper.

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It is common knowledge that Mg is very light and high specific strength material. But there is a problem that Mg alloy easily burns during its machining, because the ignition point of Mg is 700K.[1] The ignition point of new Mg alloy to which Ca is added is about 1000K. This new Mg alloy is called non-combustible Mg alloy. As a result, many inclusions exist in Mg alloy. Then, fatigue test was carried out and gave evidence that inclusions have an effect on the fatigue strength. Then relationships between size of inclusions and fatigue limit were drawn. Therefore, the fatigue limit can be predicted by estimating the maximum inclusion size. The method of estimating the maximum inclusion size is “Estimation for particle size distribution in materials“[2] .

A feasibility study of next generation 6 kHz ArF laser for lithography is presented. High repetition rate operation of excimer lasers faces two technical challenges: 1) the occurrence of acoustic waves caused by the discharge in the laser chamber and 2) the huge energy consumption of the large gas flow fans. This paper describes our approach to dampen the acoustic waves. A computer simulation of acoustic wave generation inside the discharge chamber was done. The simulation correlates well with Schlieren photography measurements that visualized the acoustic waves. Based on these results, a chamber for 6 kHz repetition rate was newly designed. Measured spectral data (FHWM and E95) proved that the acoustic wave perturbation was remarkably reduced. A very efficient design method for high repetition rate laser chamber has therefore been established.

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