Development of a Liquid-Jet Laser-Produced-Plasma Light Source for EUV Lithography

摘要

The Extreme Ultraviolet Lithography System Development Association (EUVA) was established in Japan in May 2002 and is supported by the Ministry of Economy, Trade and Industry (METI). EUVA started the light source development in September 2002. This development is done by the association members Gigaphoton, Ushio, Komatsu, Canon, Nikon, the National Institute of Advanced Industrial Science and Technology (AIST) and several Japanese universities. The target of the four-year project is the development of a EUV light source with 10W clean focus point power. For the end of the fiscal year 2003 (March 2004) the development of a 4W EUV light source (clean focus point power) is planned. Both, Laser-Produced-Plasma (LPP) and Discharge-Produced-Plasma (DPP) EUV light sources are investigated at first. Our group at the EUVA Hiratsuka R&D Center is working on LPP sources. We are currently focusing on the development of a driver laser and a liquid Xenon plasma target. The laser is a Nd: YAG MOPA (Master Oscillator and Power Amplifier) system oscillating at 1064nm. Average power, repetition rate and pulse duration of the laser system are 500 Watt, 10 kHz and 30nsec, respectively. The Xenon liquefaction system operates at a maximum pressure of 5MPa and a temperature range between 160 K and 190 K. The pressure inside the vacuum chamber is below 0.1Pa during system operation. This paper presents the current status of the EUV system component development as well as first experimental results of generated EUV radiation.