Resonator for single line selection

A high repetition rate excimer or molecular fluorine laser system, comprising:

• a discharge chamber filled with a laser gas mixture at least including a halogen-containing gas and a buffer gas;
• a power supply circuit including a pulser module powered by a high voltage power supply;
• a plurality of electrodes within the discharge chamber connected to, and receiving electrical pulses from, the power supply circuit thereby energizing the gas mixture at a repetition rate of at least 2 kHz;
• a resonator for generating a laser beam including the discharge chamber and a pair of resonator reflector elements, and the resonator including at least one line-narrowing optical element and at least one aperture for reducing a bandwidth of the laser beam;
• a spectrometer including spectral monitoring components measuring one or more parameters of wavelength, bandwidth and spectral purity of a spectral distribution of the beam;
• and
• a processor for receiving a signal relating to the measured one or more parameters of the spectral distribution and controlling the line-narrowing module to tune at least one of the wavelength, bandwidth and spectral purity parameters of the beam;
• wherein said line-narrowing optical element serves to disperse said beam such that only a selected portion of the spectral distribution of the beam incident at said line-narrowing optical element remains within a beam acceptance angle defined in part by said aperture;
• and
• wherein said aperture is cooled, thereby resisting heat build-up due to exposure to the high repetition rate beam, to prevent distortions due to thermal heating of the aperture.

An excimer or molecular fluorine laser system, comprising:

• a discharge chamber filled with a laser gas mixture at least including a halogen-containing gas and a buffer gas;
• a power supply circuit including a pulser module powered by a high voltage power supply;
• a plurality of electrodes within the discharge chamber connected to, and receiving electrical pulses from, the power supply circuit thereby energizing the gas mixture;
• a resonator for generating a laser beam including the discharge chamber and a pair of resonator reflector elements, and the resonator including at least one line-narrowing optical element on one side of the discharge chamber for reducing a bandwidth of the laser beam;
• a spectrometer including spectral monitoring components measuring one or more parameters of wavelength, bandwidth and spectral purity of a spectral distribution of the beam;
• a processor for receiving a signal relating to the measured one or more parameters of the spectral distribution and controlling the line-narrowing module to tune at least one of the wavelength, bandwidth and spectral purity parameters of the beam, wherein a substantially total intensity of said laser beam impinges upon said at least one line-narrowing optical element and is thereby line-narrowed before being outcoupled from the laser resonator, and particularly such that radiation emanating from the laser chamber and propagating toward said same side of the laser chamber, and which is output coupled on a first pass and never traverses optics on the opposite side of the laser chamber, passes through said angularly-dispersive line-narrowing optical element suppressing background radiation and improving spectral purity in the output beam;
• and
• wherein said line-narrowing optical element serves to disperse said beam such that only a selected portion of the spectral distribution of the beam incident at said line-narrowing optical element remains within a beam acceptance angle;
• and
• wherein the laser beam is output coupled from the resonator on the same side of the discharge chamber as the at least one line-narrowing optical element, and said line-narrowing optical element is disposed in a same modular unit from which said beam is output coupled.

An excimer or molecular fluorine laser system, comprising:

• a discharge chamber filled with a laser gas mixture at least including a halogen-containing gas and a buffer gas;
• a power supply circuit including a pulser module powered by a high voltage power supply;
• a plurality of electrodes within the discharge chamber connected to, and receiving electrical pulses from, the power supply circuit thereby energizing the gas mixture;
• a resonator for generating a laser beam including the discharge chamber and a pair of resonator reflector elements, the resonator including a line-narrowing module including at least one line-narrowing optical element on one side of the laser chamber and at least one aperture for reducing a bandwidth of the laser beam, wherein said line-narrowing optical element serves to disperse said beam such that only a selected portion of the spectral distribution of the beam incident at said line-narrowing optical element remains within a beam acceptance angle as defined at least in part by said aperture;
• a spectrometer including spectral monitoring components measuring one or more parameters of wavelength, bandwidth and spectral purity of a spectral distribution of the beam;
• and
• a processor for receiving a signal relating to the measured one or more parameters of the spectral distribution and controlling the line-narrowing module to tune at least one of the wavelength, bandwidth and spectral purity parameters of the beam;
• wherein the laser beam is output coupled from the resonator on the same side as the line-narrowing module by polarization coupled reflection from an optical surface, such that radiation emanating from the laser chamber and propagating toward said same side of the laser chamber, and which is output coupled on a first pass and never traverses optics on the opposite side of the laser chamber, passes through said angularly-dispersive line-narrowing optical element suppressing background radiation and improving spectral purity in the output beam.