A tunable, ultrahigh-spectral-brightness ArF* excimer laser source

Abstract

An extremely high spectral‐brightness ArF* 193‐nm excimer source with the following output pulse characteristics is described: ∼30‐mJ pulse energy, ∼5‐nsec pulse duration, spectral width less than 260 MHz, absolute frequency control to within 1.8 GHz, ∼5×15‐μrad beam divergence, and repetition rate up to 10 Hz. Within the uncertainty of measurement, the spectral width of the output radiation is Fourier transform limited and the beam divergence corresponds to the diffraction limit of the radiating aperture.