Product Code: ICAL07_M1201

EUV and Debris Characteristics of a Laser-Produced Tin Plasma using a Colloidal Tin Dioxide Jet Target
Authors:
Masahito Katto, University of Miyazaki; Miyazaki Japan
Masanori Kaku, University of Miyazaki; Miyazaki Japan
Shoichi Kubodera, University of Miyazaki; Miyazaki Japan
Presented at ICALEO 2007

Characteristics of emitted particles as well as EUV emissions from a laser-produced tin plasma using a colloidal tin dioxide nano-particle jet target were investigated as a possible EUV lithography light source. By using double nano-second YAG laser pulses with an optimum delay of 100 ns, the EUV conversion efficiency of 1.2% at 13.5 nm was observed. The energy and strength of ionic debris were simultaneously decreased as a result of an expanding low-density plasma produced by the first laser pulse. Total amount of the debris was evaluated as a deposited amount on a witness plate placed near the colloidal jet target. The result showed a similar deposition thickness speed of 0.6 nm per 10,000 laser pulses for both single and double laser irradiation modes, which may have been limited by vacuum capacity of the working chamber and/or by vaporized amount of the target. Regulation of the deposited debris by use of heat and light energy is under investigation.