Patent ID: 7075963

Claim:
An excimer or molecular fluorine laser, comprising: a discharge chamber filled with a gas mixture including molecular fluorine; a plurality of electrodes within the discharge chamber connected to a pulsed discharge circuit for energizing the gas mixture; two resonator reflector surfaces disposed on opposite sides of the discharge chamber; and a line-narrowing module adjacent to one of the resonator reflector surfaces, wherein the discharge chamber, resonator reflector surfaces, and line-narrowing module form a resonator for generating a laser beam; wherein the line-narrowing module includes: a beam expander disposed in a path of the laser beam and having one or more optical elements for expanding the beam and reducing a divergence of the beam; a reflection grating disposed in the path of the laser beam; a heat sink in thermal contact with the reflection grating; and means for tuning a wavelength of the laser beam output by the line-narrowing module.