Line width narrowing module and excimer laser

Abstract

The invention discloses a linewidth narrowing module and an excimer laser, and the linewidth narrowing module comprises a prism group which is used for adjusting a laser beam; a reflecting mirror which is arranged at one end of the prism group, wherein the reflecting mirror is used for reflecting the adjusted light beams; an optical grating which is arranged on one side of the prism group and oneside of the reflecting mirror, receives the reflected light beams, is matched with the prism group to carry out spectrum control on the light beams, and comprises a first end and a second end which are oppositely arranged, the first end is close to the reflecting mirror, and the second end is close to the reflecting mirror, wherein the temperature of the first end is higher than that of the secondend; an air blowing pipe which faces the optical grating, a plurality of air blowing holes are formed in the air blowing pipe, wherein the air flow of the air blowing holes close to the first end islarger than that of the air blowing holes close to the second end. The line width narrowing module can improve the stability of an output spectrum.

Description

technical field [0001] The invention relates to the technical field of spectrum control, in particular to a line width narrowing module and an excimer laser. Background technique [0002] The line width narrowing module is an important part of the excimer laser, and the excimer laser is generally controlled by the line width narrowing module. see figure 1 , the measurement index of excimer laser spectral output is generally defined by full width at half maximum (FWHM) and spectral purity (E95), where FWHM is the spectral line width at which the light intensity drops to half of the peak light intensity, and E95 is the region containing 95% energy the spectral line width. The main factors affecting the above measurement indicators include the divergence angle of the laser beam, the beam expansion ratio of the prism group, the laser wavelength, the diffraction angle of the grating, and the length of the discharge cavity. For a certain discharge cavity and line width narrowin...

AI Technical Summary

Problems solved by technology

For a certain discharge cavity and line width narrowing module, the laser wavefront will change due to the thermal effect of the line width narrowing module, resulting in increased divergence angle and spectral broadening during laser transmission.

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