Gas discharge laser chamber improvements

    公开(公告)号:US07522650B2

    公开(公告)日:2009-04-21

    申请号:US10815387

    申请日:2004-03-31

    IPC分类号: H01S3/22

    摘要: A method and apparatus if disclosed which may comprise a high power high repetition rate gas discharge laser UV light source which may comprise: a gas discharge chamber comprising an interior wall comprising a vertical wall and an adjacent bottom wall; a gas circulation fan creating a gas flow path adjacent the interior vertical wall and the adjacent bottom wall; an in-chamber dust trap positioned a region of low gas flow, which may be along an interior wall and may comprise at least one meshed screen, e.g., a plurality of meshed screens, which may comprise at least two different gauge meshed screens. The dust trap may extend along the bottom interior wall of the chamber and/or a vertical portion of the interior wall. The dust trap may comprise a first meshed screen having a first gauge; a second meshed screen having a second gauge smaller than the first gauge; and the second meshed screen intermediate the first meshed screen and the interior wall. The chamber may comprise a plurality of dust collecting recesses in at least one of the vertical interior wall and the bottom wall of the chamber which may be selected from a group comprising a one-part recess and a multi-part recess, which may comprise two sections angled with respect to each other. The dust trap may comprise a pressure trap positioned between a portion of a main insulator and an interior wall of the chamber. The chamber may comprise a gas circulating fan comprising a cross-flow fan with a fan cutoff that may comprise a vortex control pocket. The chamber may comprise a preionization mechanism comprising a preionization tub containing a ground rod within an elongated opening in the preionization tube that may comprise a compliant member, an automatic preionization shut-off mechanism, a preionization onset control mechanism and/or a focusing element. The chamber may comprise an elongated baffle plate that may comprise a plurality of pyramidal structures including varying numbers of generally pyramidal elements and oriented in groups of varying numbers of generally pyramidal elements and oriented along and transverse to the longitudinal axis. Acoustic resonances within the chamber may also be reduced by introducing an artificial jitter into the timing of the laser discharges varying the inter-pulse period randomly or in a repeating pattern from pulse to pulse within a burst.

    Line narrowing module
    8.
    发明授权

    公开(公告)号:US07366219B2

    公开(公告)日:2008-04-29

    申请号:US11000684

    申请日:2004-11-30

    IPC分类号: H01S3/22

    摘要: A line narrowing method and module for a narrow band DUV high power high repetition rate gas discharge laser producing output laser light pulse beam pulses in bursts of pulses, the module having a nominal optical path are disclosed which may comprise: a dispersive center wavelength selection optic moveably mounted within an optical path of the line narrowing module, selecting at least one center wavelength for each pulse determined at least in part by the angle of incidence of the laser light pulse beam containing the respective pulse on the dispersive wavelength selection optic; a first tuning mechanism operative in part to select the angle of incidence of the laser light pulse beam containing the respective pulse upon the dispersive center wavelength selection optic, by selecting an angle of transmission of the laser light pulse beam containing the pulse toward the dispersive center wavelength selection optic; a second tuning mechanism operative in part to select the angle of incidence of the laser light pulse beam containing the respective pulse by changing the position of the dispersive center wavelength selection optic relative to the nominal optical path of the line narrowing module; wherein the second tuning mechanism coarsely selects a value for the center wavelength and the first tuning mechanism more finely selects the value for the center wavelength. The apparatus and method may further comprise at least one beam expanding and redirecting prism in the optical path of the line narrowing module; the first tuning mechanism selecting an angle of incidence of the at least a first spatially defined portion of the laser light pulse beam by changing the position of the at least one beam expanding prism relative to the nominal optical path of the line narrowing module. The first and second tuning mechanisms may be controlled by a center wavelength controller during a burst based upon feedback from a center wavelength detector detecting the center wavelength of at least one other pulse in the burst of pulses and the controller providing the feedback based upon an algorithm employing the detected center wavelength for the at least one other pulse in the burst. The first tuning mechanism may comprise an electro-mechanical course positioning mechanism and a fine positioning mechanism comprising an actuatable material that changes position or shape when actuated.