Abstract:
According to aspects of an embodiment of the disclosed subject matter, a line narrowed high average power high pulse repetition laser micro-photolithography light source bandwidth control method and apparatus are disclosed which may comprise a bandwidth metrology module measuring the bandwidth of a laser output light pulse beam pulse produced by the light source and providing a bandwidth measurement; a bandwidth error signal generator receiving the bandwidth measurement and a bandwidth setpoint and providing a bandwidth error signal; an active bandwidth controller providing a fine bandwidth correction actuator signal and a coarse bandwidth correction actuator signal responsive to the bandwidth error. The fine bandwidth correction actuator and the coarse bandwidth correction actuator each may induce a respective modification of the light source behavior that reduces bandwidth error. The coarse and fine bandwidth correction actuators each may comprise a plurality of bandwidth correction actuators.
Abstract:
An apparatus includes a light source that produces a light beam, a bandwidth measurement system, a plurality of bandwidth actuation systems, and a control system. Each bandwidth actuation system includes one or more bandwidth actuators and each bandwidth actuation system is connected to an optical feature that is optically coupled to the produced light beam and operable to modify the connected optical feature to select a bandwidth within a bandwidth range of the produced light beam. The control system is connected to the bandwidth measurement system and to the plurality of bandwidth actuation systems. The control system is configured to switch between activating and operating a first bandwidth actuation system and activating and operating a second bandwidth actuation system independently and separately of activating and operating the first bandwidth actuation system based on a provided bandwidth measurement and a selected target bandwidth.
Abstract:
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 fitter 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.
Abstract:
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 fitter 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.
Abstract:
According to aspects of an embodiment of the disclosed subject matter, a line narrowed high average power high pulse repetition laser micro-photolithography light source bandwidth control method and apparatus are disclosed which may comprise a bandwidth metrology module measuring the bandwidth of a laser output light pulse beam pulse produced by the light source and providing a bandwidth measurement; a bandwidth error signal generator receiving the bandwidth measurement and a bandwidth setpoint and providing a bandwidth error signal; an active bandwidth controller providing a fine bandwidth correction actuator signal and a coarse bandwidth correction actuator signal responsive to the bandwidth error. The fine bandwidth correction actuator and the coarse bandwidth correction actuator each may induce a respective modification of the light source behavior that reduces bandwidth error. The coarse and fine bandwidth correction actuators each may comprise a plurality of bandwidth correction actuators.
Abstract:
A gas discharge laser system bandwidth control mechanism and method of operation for controlling bandwidth in a laser output light pulse generated in the gas discharge laser system is disclosed which may comprise a bandwidth controller which may comprise an active bandwidth adjustment mechanism; a controller actively controlling the active bandwidth adjustment mechanism utilizing an algorithm implementing bandwidth thermal transient correction based upon a model of the impact of laser system operation on the wavefront of the laser light pulse being generated and line narrowed in the laser system as it is incident on the bandwidth adjustment mechanism. The controller algorithm may comprises a function of the power deposition history in at least a portion of an optical train of the gas discharge laser system, e.g., a linear function, e.g., a combination of a plurality of decay functions each comprising a respective decay time constant and a respective coefficient.
Abstract:
A multi-chambered excimer or molecular halogen gas discharge laser system comprising at least one oscillator chamber and at least one amplifier chamber producing oscillator output laser light pulses that are amplified in the at least one power chamber, having a fluorine injection control system and a method of using same is disclosed, which may comprise: a halogen gas consumption estimator: estimating the amount of halogen gas that has been consumed in one of the at least one oscillator chamber based upon at least a first operating parameter of one of the least one oscillator chamber and the at least one amplifier chamber, and the difference between a second operating parameter of the at least one oscillator chamber and the at least one amplifier chamber, and estimating the amount of halogen gas that has been consumed in the other of the at least one oscillator chamber and the at least one amplifier chamber based upon at least a third operating parameter of the other of the at least one oscillator chamber and the at least one amplifier chamber, and producing an output representative of an estimated halogen gas consumption in the at least one oscillator chamber and of the halogen gas consumption in the at least one amplifier chamber, and a halogen gas injection controller determining the amount of halogen gas injection for the at least one oscillator chamber and the at least one amplifier chamber based upon the estimated fluorine consumption outputs from the fluorine consumption estimator and a cost function comprising a plurality of weighted injection decision determinations.
Abstract:
A gas discharge laser system bandwidth control mechanism and method of operation for controlling bandwidth in a laser output light pulse generated in the gas discharge laser system is disclosed which may comprise a bandwidth controller which may comprise an active bandwidth adjustment mechanism; a controller actively controlling the active bandwidth adjustment mechanism utilizing an algorithm implementing bandwidth thermal transient correction based upon a model of the impact of laser system operation on the wavefront of the laser light pulse being generated and line narrowed in the laser system as it is incident on the bandwidth adjustment mechanism. The controller algorithm may comprises a function of the power deposition history in at least a portion of an optical train of the gas discharge laser system, e.g., a linear function, e.g., a combination of a plurality of decay functions each comprising a respective decay time constant and a respective coefficient.
Abstract:
A multi-chambered excimer or molecular halogen gas discharge laser system comprising at least one oscillator chamber and at least one amplifier chamber producing oscillator output laser light pulses that are amplified in the at least one power chamber, having a fluorine injection control system and a method of using same is disclosed, which may comprise: a halogen gas consumption estimator: estimating the amount of halogen gas that has been consumed in one of the at least one oscillator chamber based upon at least a first operating parameter of one of the least one oscillator chamber and the at least one amplifier chamber, and the difference between a second operating parameter of the at least one oscillator chamber and the at least one amplifier chamber, and estimating the amount of halogen gas that has been consumed in the other of the at least one oscillator chamber and the at least one amplifier chamber based upon at least a third operating parameter of the other of the at least one oscillator chamber and the at least one amplifier chamber, and producing an output representative of an estimated halogen gas consumption in the at least one oscillator chamber and of the halogen gas consumption in the at least one amplifier chamber, and a halogen gas injection controller determining the amount of halogen gas injection for the at least one oscillator chamber and the at least one amplifier chamber based upon the estimated fluorine consumption outputs from the fluorine consumption estimator and a cost function comprising a plurality of weighted injection decision determinations.