Title :
An ultra-line-narrowed high-power F2 laser for dioptric design microlithography exposure tools
Author :
Ariga, Tatsuya ; Mizoguchi, Hakaru
Author_Institution :
Innovation Center, Komatsu Ltd., Kanagawa, Japan
Abstract :
An ultra-line-narrowed high-power and high-repetition rate F2 laser system has been developed for 157-nm microlithography exposure tools with dioptric projection design. The injection locked system (ILS) consists of a low-power seed laser with ultra-narrow spectral linewidth and a high-gain amplifier. More than 25-W output power, a spectral linewidth below 0.2 pm full-width at half-maximum (FWHM) and an energy stability (3-sigma) below 10% have been obtained at a 5-kHz repetition rate and for a delay time range between the two laser stages of about 15 ns. Directly compared with a master oscillator power amplifier system, the ILS had a better performance related to output energy, energy stability, and laser pulse duration.
Keywords :
fluorine; gas lasers; injection locked oscillators; laser stability; nanolithography; optical design techniques; optical projectors; spectral line narrowing; 15 ns; 157 nm; 5 kHz; F2; F2 laser; delay time; dioptric design; dioptric projection; energy stability; full-width at half-maximum; high-gain amplifier; high-power laser; high-repetition rate laser system; injection locked system; laser pulse duration; low-power seed laser; master oscillator power amplifier; microlithography exposure tools; ultraline-narrowed laser; ultranarrow spectral linewidth; Gas lasers; Injection-locked oscillators; Laser stability; Lenses; Optical amplifiers; Optical design; Optical pulses; Power amplifiers; Power lasers; Pulse amplifiers;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2004.837713
