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.

Abstract: A gas laser oscillator includes a supply-side valve for regulating a laser gas supply to a gas chamber, an exhaust-side valve for regulating a laser gas exhaust from the gas chamber, a gas pressure measuring device for measuring a pressure in the gas chamber, and a control device functioning as a laser gas replacement measuring device. The control device makes a first measurement and a second measurement of the pressure in the gas chamber by a gas pressure measuring device at a predetermined time interval during the vacuuming or purging of the gas chamber, and determines the laser gas replacement amount per unit time during the laser oscillating operation, based on the results of the first and second measurements.

Abstract: Gas lasers including nanoscale catalysts and methods for producing such lasers are disclosed herein. In one embodiment, a gas laser includes a gas containment structure having a gas discharge region and a laser gas medium in the gas discharge region. The gas laser also includes a plurality of optical elements spaced apart from each other at opposite ends of the gas discharge region to form a laser resonator. The gas laser further includes a nanoscale catalyst proximate to and in communication with the gas discharge region to modify oxidation and/or decomposition processes of selected components of the laser gas medium. In one embodiment, the nanoscale catalyst can include a metal-oxide support substrate carrying a plurality of nanoscale particulates. The nanoscale particulates can be composed of one or more of the following: gold, silver, or platinum, and have an average size of about 1-50 nm.

Abstract: A method and apparatus are disclosed which may comprise predicting the gas lifetime for a gas discharge laser light source for a photolithography process, the light source comprising a halogen containing lasing gas may comprise: utilizing at least one of a plurality of laser operating input and/or output parameters; utilizing a set of at least one parameter of utilization in the photolithography process to determine a gas use model in relation to the respective input or output parameter; predicting the end of gas life based upon the model and a measurement of the respective input or output parameter. The parameter may comprise a pulse utilization pattern.

Abstract: A laser processing system includes a laser processing means, a gas mixing unit, and a controller. The controller controls and adjusts the composition of the process gas for laser processing. The controller includes a data storage for technology tables by means of which the composition of the process gas is controlled and adjusted.

Abstract: Gas lasers including nanoscale catalysts and methods for producing such lasers are disclosed herein. In one embodiment, a gas laser includes a gas containment structure having a gas discharge region and a laser gas medium in the gas discharge region. The gas laser also includes a plurality of optical elements spaced apart from each other at opposite ends of the gas discharge region to form a laser resonator. The gas laser further includes a nanoscale catalyst proximate to and in communication with the gas discharge region to modify oxidation and/or decomposition processes of selected components of the laser gas medium. In one embodiment, the nanoscale catalyst can include a metal-oxide support substrate carrying a plurality of nanoscale particulates. The nanoscale particulates can be composed of one or more of the following: gold, silver, or platinum, and have an average size of about 1-50 nm.

Abstract: To provide an excimer laser device and method in which the frequency of full gas exchange within the laser chamber is reduced, and more preferably full gas exchange is made unnecessary. The gas supply device and gas exhaust device are controlled so that the laser gas in the laser chamber is partially exchanged in a gas exchange quantity that maintains the quantity of impurities in the laser chamber at or below a fixed level. Also, the gas exchange quantity is obtained using the total quantity of output light energy reduction A, the total gas pressure in the laser chamber P, and output light energy reduction quantity per unit time k, for the case where partial gas exchange is repeated infinitely in the laser chamber.

Abstract: In an laser oscillator (100), a blower (10, 20, 120) for circulating a laser medium between an electric discharge tube (102) and a circulating passage (104) includes: a casing (12) having a suction port (12a) and an exhaust port (12b); and a blade (18) pivotally supported in the casing (12) so that the blade (18) can face the suction port (12a) and the exhaust port (12b). The blade (18) is formed into a shape in which a diameter of the blade (18) is different at a position on a cross section perpendicular to a rotary central line (O), and a gap (Go) between a portion, in which a diameter of the blade (18) is relatively large, and the casing is larger than a gap (Gi) between a portion, in which a diameter of the blade (18) is relatively small, and the casing. Due to the foregoing, a highly reliable blower used for a laser oscillator, the reduction of the blower efficiency of which is suppressed to be as small as possible, can be provided.

Abstract: An apparatus includes a gas chamber comprising a gas feed nozzle, an exhaust nozzle, and a window. The apparatus also includes a first partial reflector, in the gas chamber, sharing an optical path with the exhaust nozzle, and the window. Optionally, The apparatus includes a gas source communicating with the gas feed nozzle. Optionally, the gas source includes a gas having an ionization potential higher than air and a nonlinear index of refraction lower than air.

Abstract: A gas laser oscillator (2) that excites a laser gas to generate laser light includes a circulation path (9) for the laser gas, a circulation means (14) for circulating the laser gas through the circulation path, a pressure detection means (16) for detecting the pressure of the laser gas in the circulation path, an electric power detection means (11) for detecting electric power to drive the circulation means, a storage means (35) for storing the relationship between the pressure of the laser gas and the electric power of the circulation means during the period of normal operation of the circulation means for each kind of the laser gas, and a laser gas determination means (31).

Abstract: The present invention relates to a fluorine gas discharge laser system and control of replenishment of fluorine gas as the gas discharge laser operates and consumes fluorine.

Abstract: Output beam parameters of a gas discharge laser are stabilized by maintaining a molecular fluorine component at a predetermined partial pressure using a gas supply unit and a processor. The molecular fluorine is subject to depletion within the discharge chamber. Gas injections including molecular fluorine can increase the partial pressure of molecular fluorine by a selected amount. The injections can be performed at selected intervals to maintain the constituent gas substantially at the initial partial pressure. The amount per injection and/or the interval between injections can be varied, based on factors such as driving voltage and a calculated amount of molecular fluorine in the discharge chamber. The driving voltage can be in one of multiple driving voltage ranges that are adjusted based on system aging. Within each range, gas injections and gas replacements can be performed based on, for example, total applied electrical energy or time/pulse count.

Abstract: A gas laser oscillator includes a supply-side valve for regulating a laser gas supply to a gas chamber, an exhaust-side valve for regulating a laser gas exhaust from the gas chamber, a gas pressure measuring device for measuring a pressure in the gas chamber, and a control device functioning as a laser gas replacement measuring device. The control device makes a first measurement and a second measurement of the pressure in the gas chamber by a gas pressure measuring device at a predetermined time interval during the vacuuming or purging of the gas chamber, and determines the laser gas replacement amount per unit time during the laser oscillating operation, based on the results of the first and second measurements.

Abstract: A method of minimizing contamination of optical components of a laser resonator is disclosed. The resonator components are located in an enclosure, which may contain contaminants including water vapor and organic favor released by the optical components, mounts of the optical components, or the enclosure itself. The enclosure may also contain suspended particulate matter. In order to reduce the level of these contaminants, a purging system extracts gas from the enclosure and passes the gas through a desiccant, an organic vapor trapping material, and a particulate matter filter then returns the extracted gas to the enclosure. The purging system is particularly useful for ultrafast lasers and ultraviolet lasers where the power of the laser radiation increases the probability of destabilizing reactions between laser radiation and contaminants.

Abstract: Feedback timing control equipment and process for an injection seeded modular gas discharge laser. A preferred embodiment is a system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs of about 20 to 40 Watts or greater. The feedback timing control is programmed to permit in some circumstances discharges timed so that no significant laser energy is output from the system. Use of this technique permits burst mode operation in which the first discharge of a burst is a no-output discharge so that timing parameters for each of the two chambers can be monitored before the first laser output pulse of the burst. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber.

Abstract: A solid generator laser provides device simplicity and fuel regeneration without relying upon highly-corrosive or unstable fuels. The laser system includes a fuel supply system that provides a solid fuel to a laser. The laser processes the fuel products to produce at least a solid waste product and a gaseous waste product. A fuels regeneration system receives the solid and gaseous wastes at a reagent production system to replenish the fuel products in the fuel supply system. Rather than relying upon corrosive fuels such as BHP, then, the laser suitably processes solid peroxide (e.g. Na2O2) and a halide (e.g. hydrogen or deuterium halide) to form a salt, water and singlet delta oxygen that may be used to induce a lasing effect. The processes and structures described herein may be used, for example, with chemical oxygen iodine lasers and the like.

Abstract: A laser oscillator capable of preventing contamination of optical components by organic matter such as oil mist. Gas laser medium in an optical resonator constituted by optical components is pumped by an electric discharge generated in an electric discharge tube to produce a laser beam. The gas medium flows at high speed in the electric discharge tube incorporated in a circulating path including a blower. A part of lubrication oil of the blower is evaporated and mixed into the gas medium. Since the optical components are cooled by retaining mechanisms to prevent temperature rise of the components and a gas stagnation occurs between the optical component and the electric discharge tube, the evaporated oil mist tends to be congealed and adhered to a surface of the optical component. A photocatalyst arranged in the vicinity of the optical component effectively decomposes and removes the oil mist.

Abstract: A gas laser oscillator achieving a substantial increase in laser output is provided. This gas laser oscillator includes a permeable screen plate at a position of a laser gas passage and can increase the laser output substantially by suppressing and uniformizing laser gas pulsation in a discharge tube.

Abstract: A solid-state laser apparatus includes a cavity 17 for storing a laser diode 40 and a laser medium 6 to be excited by the laser diode 40, and a storage unit 70, for communicating with the cavity 17 and for internally storing a drying agent 71. A moisture permeable film 72 is formed at openings 73 whereat the cavity 17 and the storage unit 70 communicate with each other.

Abstract: There is to provide a laser apparatus that emits a laser beam by exciting gas enclosed in a chamber, including a gas characteristic detecting mechanism for detecting a characteristic of the gas in the chamber, and a calculation mechanism for calculating an oscillation wavelength and/or a wavelength spectral bandwidth of the laser beam based on a detected result by the gas characteristic detecting mechanism.

Abstract: A line-narrowing module for a laser includes a prism beam expander and a grating preferably attached to a heat sink. A pressure-controlled enclosure filled with an inert gas seals the grating and/or other elements of the line-narrowing module. The pressure in the enclosure is adjusted for tuning the wavelength. Preferably, the pressure is controlled by controlling the flow of an inert gas through the enclosure. A pump may be used, or an overpressure flow may be used. Alternatively, a prism of the beam expander or an etalon may be rotatable for tuning the wavelength.

Abstract: An oscillator-amplifier gas discharge laser system and method is disclosed which may comprise a first laser unit which may comprise a first discharge region which may contain an excimer or molecular fluorine lasing gas medium; a first pair of electrodes defining the first discharge region containing the lasing gas medium, a line narrowing unit for narrowing a spectral bandwidth of output laser light pulse beam pulses produced in said first discharge region; a second laser unit which may comprise a second discharge chamber which may contain an excimer or molecular fluorine lasing gas medium; a second pair of electrodes defining the second discharge region containing the lasing gas medium; a pulse power system providing electrical pulses to the first pair of electrodes and to the second pair of electrodes producing gas discharges in the lasing gas medium between the respective first and second pair of electrodes, and laser parameter control mechanism modifying a selected parameter of a selected laser output lig

Abstract: An integrated dual source recycling system and method for a chemical oxygen-iodine laser system is described. The recycling system primarily includes: (1) a first collection system for collecting an amount of spent basic hydrogen peroxide comprised of spent aqueous potassium chloride; and (2) a second collection system for collecting an amount of the spent laser exhaust gas. Several processing systems are also employed to convert the spent aqueous potassium chloride and the spent laser exhaust gas into hydrogen peroxide and potassium hydroxide which are mixed together to form fresh basic hydrogen peroxide. Additionally, the spent laser exhaust gas is recycled back into molecular nitrogen, molecular iodine, molecular oxygen, and molecular chlorine.

Abstract: An axial direction excitation type F2 laser apparatus comprises a discharge tube consisting of an insulating cylinder and metal electrodes at both ends of thereof, and a reflecting mirror or a transmitting mirror, constituting a resonator, outside the electrodes. A high voltage for pulse discharge is applied to the electrodes from a drive circuit. Total gas pressure in the discharge tube is set in a range between 10 Torr. and 100 Torr., and concentration of F2 gas to total gas in the discharge tube is set to be in a range between 0.2% and 2.0%. This low-pressure axial direction excitation type F2 laser apparatus having small size and high efficiency can be provided at a low cost.

Abstract: An injection seeded modular gas discharge laser system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 mJ or greater. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. The chambers can be controlled separately permitting separate optimization of wavelength parameters in the master oscillator and optimization of pulse energy parameters in the amplifying chamber. A preferred embodiment in an ArF excimer laser system configured as a MOPA and specifically designed for use as a light source for integrated circuit lithography. In the preferred MOPA embodiment, each chamber comprises a single tangential fan providing sufficient gas flow to permit operation at pulse rates of 4000 Hz or greater by clearing debris from the discharge region in less time than the approximately 0.25 milliseconds between pulses.

Abstract: The present invention provides systems and methods for filtering particles and assisting gas flow management within laser systems. In one embodiment, a laser apparatus (100) includes an elongate laser chamber defining a chamber cavity (130) and an electrode structure (140) disposed therein. The electrode structure includes an anode (148) spaced apart from a cathode (146). The laser includes an elongate baffle (174) disposed in the laser chamber. The baffle is adapted to arrest a plurality of particles generated within the chamber. In this manner, the baffle operates as a passive filtration system to help filter particles generated within the chamber during laser operation, and may further provide gas flow management capabilities.

Abstract: An automatic F2 laser gas control, for a modular high repetition rate ultraviolet gas discharge laser. The laser gas control includes techniques, monitors, and processor for monitoring the F2 consumption rates through the operating life of the laser system. These consumption rates are used by a processor programmed with an algorithm to determine F2 injections needed to maintain laser beam quality within a delivery range. Preferred embodiments include F2 controls for a two-chamber MOPA laser system.

Abstract: A laser oscillator includes: electrode tubes 15, for employing a discharge to excite a laser gas 10, and for generating a laser beam 11; a box 13, for storing parts, such as the electrode tubes 15; and an optical catalyst layer 20, which is formed on the inner walls of the box 13.

Abstract: A gas scrubber comprises a gas inlet pipe that provides the scrubber with gases to be processed; means for initiating reactions of decomposition that is directed to initialize the decomposition of gases; an oxygen and natural gas inlet pipes to provide the necessary gases for combustion; a chamber of decomposition into which the gases to be processed are decomposed under thermal process carried out by combustion; and means for scrubbing byproducts produced in the chamber of decomposition. The means for initiating the reactions of decomposition is directed to initialize the decomposition of gas through producing radicals thereof. Thereby, the decomposition of gases under combustion in the chamber of decomposition can be accelerated, and less thermal energy is required from the combustion.

Abstract: A laser having a lasing chamber and a semiconductor pumping device with trivalent titanium ions dissolved in a liquid host within the lasing chamber. Since the host is a liquid, it can be removed from the optical cavity when it becomes heated avoiding the inevitable optical distortion and birefringence common to glass and crystal hosts.

Abstract: The present invention relates to a long pulse gas laser apparatus for lithography further improved in the laser oscillation efficiency and stability increased by addition of xenon gas. A gas laser apparatus for lithography has a pair of discharge electrodes 2 provided in a laser chamber 1 and emits laser beam having a laser pulse width (Tis) of not less than 40 ns by exciting a laser gas sealed in the laser chamber 1 by electric discharge between the pair of discharge electrodes 2, the laser gas containing xenon in an amount not less than 2 ppm and not more than 100 ppm in partial pressure ratio. The laser gas has been heated at least when the laser beam is emitted.

Abstract: Methods and apparatus are provided for cleaning and passivating laser discharge chambers with plasmas. In one embodiment, an oxygen based plasma is formed in a plasma source external to the laser discharge chamber by applying a radiofrequency signal to oxygen containing gases. The oxygen based plasma is drawn into the laser discharge chamber, where it reacts with contaminants and cleans internal surfaces. After cleaning, a fluorine based plasma is formed in the plasma source and drawn into the laser discharge chamber to passivate internal surfaces. In another embodiment, cleaning with the oxygen based plasma is not used since some level of cleaning is accomplished with the fluorine based plasma. In another embodiment, oxygen based plasmas and fluorine based plasmas are formed in the laser discharge chamber by applying a radiofrequency signal to a laser discharge chamber electrode.

Abstract: The present invention provides an excimer laser capable of producing a high quality pulsed laser beam at pulse rates of about 4,000 Hz at pulse energies of about 5 mJ or greater. A preferred embodiment is an ArF excimer laser specifically designed as a light source for integrated circuit lithography. An improved wavemeter with special software monitors output beam parameters and controls a very fast PZT driven tuning mirror and the pulse power charging voltage to maintain wavelength and pulse energy within desired limits. In a preferred embodiment two fan motors drive a single tangential fan which provides sufficient gas flow to clear discharge debris from the discharge region during the approximately 0.25 milliseconds between pulses.

Abstract: The present invention relates to a two stage laser system in which a desired spectral line width can be obtained at high output even when the integrated spectral characteristic of oscillator laser does not have the desired spectral line width, comprising an oscillator laser device 10 which has discharge electrodes 2 within a laser chamber 1 filled with laser gas containing F2 and emits laser beam which is band-narrowed by means of a band narrowing module 3 arranged in a laser resonator, and an amplifier laser device 20 which has discharge electrodes 2 within a laser chamber 1 filled with laser gas containing F2 and amplifies laser pulse injected from said oscillator laser device 10. In the system, a synchronous time interval having a predetermined spectral line width exists in laser pulse from the oscillator laser 10, and the system is set such that a discharge occurs in the amplifier laser 20 within the synchronous time interval.

Abstract: An excimer or molecular fluorine laser system includes a discharge chamber filled with a laser gas mixture at least including a halogen-containing molecular species and a buffer gas, multiple electrodes within the discharge chamber connected to a discharge circuit for energizing the gas mixture, and a resonator for generating a laser beam including an optical component made of MgF2. The optical component made of MgF2 has been previously cleaved along a predetermined plane, such that the refractive indices of the birefringent MgF2 material for orthogonal polarization components of the beam are either at least approximately equal so that the polarization of the beam due to the influence of the birefringent nature of the MgF2 material is not substantially reduced, or are approximately maximum so that at least a portion of one of the components is rejected by the resonator so that the polarization of the beam is increased due to the birefringent nature of the MgF2.

Abstract: Feedback timing control equipment and process for an injection seeded modular gas discharge laser. A preferred embodiment is a system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs of about 20 to 40 Watts or greater. The feedback timing control is programmed to permit in some circumstances discharges timed so that no significant laser energy is output from the system. Use of this technique permits burst mode operation in which the first discharge of a burst is a no-output discharge so that timing parameters for each of the two chambers can be monitored before the first laser output pulse of the burst. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber.

Abstract: Water getter devices (10) are provided which comprise a powdered water getter material (18) in a container that is permeable to gases but capable of retaining solid particles and does not need welding.

Abstract: The present invention provides a gas discharge ultraviolet laser capable of producing a high quality pulsed ultraviolet laser beam at pulse rates greater than 2000 Hz at pulse energies at 5 mJ or greater and having an enclosed beam path at least a portion of which comprises an oxidation agent. In a preferred embodiment a portion of the beam path comprises a sealed chamber containing a gas comprising a small concentration of oxygen. In one preferred embodiment the sealed chamber is an etalon chamber and the contained gas is nitrogen with an oxygen concentration of between 1.6 and 2.4 percent. In another preferred embodiments a small concentration of oxygen is added to the purge gas of a special purge compartment containing optical components exposed to high intensity output laser beam.

Abstract: An ultra-narrow band fluorine laser apparatus is provided in which a line width of a fluorine laser can be narrowed to about 0.2 to 0.3 pm without using any band-narrowing element such as an etalon. In an oscillator 11, a laser chamber 15 is provided in a stable type resonator constituted by an output mirror 13 and a totally reflecting mirror 14. The laser chamber 15 is filled with a laser gas at about 0.8 atm. As a result, when discharge is caused in the laser chamber 15 to cause laser oscillation, laser light L10 in a bandwidth of about 0.3 pm is provided. The power of the laser light L10 is increased by an amplifier 12. The amplifier 12 emits laser light L20 in a bandwidth of about 0.3 pm having laser energy of 10 mJ or more.

Abstract: A laser oscillator capable of effectively collecting and removing particulate foreign matter contained in gas laser medium flowing in a circulating path. An electric discharge section arranged in an optical resonator is incorporated into a circulating path of the gas medium including a heat exchanger and a blower. The gas laser medium flows at a high speed in the circulating path. At least one spiral-flow dust collecting mechanism is provided in the circular path downstream of the heat exchanger, and the gas laser medium discharged from the blower is supplied to the electric discharge section through the spiral-flow dust collecting mechanism. The gas laser medium containing the particulate foreign matter spirally flows around an inner pipe in a cylindrical body of the spiral-flow dust collecting mechanism.

Abstract: A method and apparatus are provided for in situ protection of sensitive optical materials from alternation or damage due to exposure to trace atmospheric components, during shipping, storage or operation. The sensitive optical material is disposed within an enclosure adaptable to be substantially sealed against the external atmosphere. A container, enclosing a sink material absorbing trace atmospheric components, is coupled to the enclosure by a gas permeable surface, which allows fast diffusion of the trace atmospheric component inside the enclosure to the sink material.

Abstract: An excimer laser gas in a laser tube 2 is excited by a microwave introduced from awaveguide 1, and electric field concentration occurs in a slit-shaped gap 3 provided in a plate member 11c, causing plasma discharge. Then the phase of plasma light is regulated and the light is resonated, to cause excimer laser light. This construction realizes plasma excitation entirely uniform along a lengthwise direction of laser light emission, and enables uniform laser light emission with minimum energy loss.

Abstract: The invention relates to a gas discharge laser including a discharge tube (1), in which a gas is present and which has at least one aperture (19) through which a laser beam emerges or at which a laser beam is reflected. For withdrawing a partial amount of the gas contained in the discharge tube (1), at least one gas withdrawal point (9) is present, from which the withdrawn gas is supplied to a sintered filter (11) for being cleaned. The cleaned gas may be led in via at least one gas inlet point (27) in the zone of the aperture (19). The invention further relates to a method of operating a gas discharge laser, and the use of a sintered filter for cleaning gas withdrawn from a discharge tube (1) of a gas discharge laser.

Abstract: A method of minimizing contamination of optical components of a laser resonator is disclosed. The resonator components are located in an enclosure, which may contain contaminants including water vapor and organic favor released by the optical components, mounts of the optical components, or the enclosure itself. The enclosure may also contain suspended particulate matter. In order to reduce the level of these contaminants, a purging system extracts gas from the enclosure and passes the gas through a desiccant, an organic vapor trapping material, and a particulate matter filter then returns the extracted gas to the enclosure. The purging system is particularly useful for ultrafast lasers and ultraviolet lasers where the power of the laser radiation increases the probability of destabilizing reactions between laser radiation and contaminants.

Abstract: The present invention provides an injection seeded modular gas discharge laser system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs of about 20 to 40 Watts or greater. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. The parameters chamber can be controlled separately permitting optimization of wavelength parameters in the master oscillator and optimization of pulse energy parameters in the amplifying chamber. A preferred embodiment is a F2 laser system configured as a MOPA and specifically designed for use as a light source for integrated circuit lithography. In this preferred embodiment, both of the chambers and the laser optics are mounted on a vertical optical table within a laser enclosure.

Abstract: An excimer or molecular fluorine laser system includes a laser chamber filled with a gas mixture at least including a halogen-containing species and a buffer gas, and multiple electrodes with the laser chamber connected to a discharge circuit energizing the gas mixture. The laser chamber is within a laser resonator generating an output beam. The resonator includes a line-narrowing package for reducing a bandwidth of the output beam. The line-narrowing package includes a grating or grism element for use with a highly reflective (HR) and/or an anti-reflective (AR) dielectric coating. The grating may serve as a resonator reflector having a dielectric HR coating. The grating may be disposed before a HR mirror and thus have a dielectric AR or HR coating when the grating is configured in transmission or reflection mode, respectively. The grating may be used as an output coupler, and may be partially reflective with or without a coating.

Abstract: An excimer or molecular fluorine laser system includes a laser chamber filled with a gas mixture at least including a halogen-containing species and a buffer gas, multiple electrodes, including a pair of main discharge electrodes and at least one preionization electrode, within the laser chamber and connected to a discharge circuit for energizing the gas mixture, and a resonator including a line-narrowing and/or selection module for generating a laser beam at high spectral purity.

Abstract: A dedusting unit for a laser optical element is provided. The dedusting unit comprises a high-voltage duct comprising a high-voltage conducting core having a first end and a second end and an insulator element disposed around the core. The first end of the core is connectable to a high voltage power supply and the second end of the core is electrically connected to a wire loop. The dedusting unit may be used in connection with a variety of gas lasers. In use, the dedusting unit is mounted to the laser tube so that the wire loop is disposed inside the gas laser tube in proximity to an optical element to be protected from dust. The dedusting unit is further mounted so that the wire loop is transverse to the resonating path of the laser light within the laser tube so that the resonating laser light may pass through the wire loop without being obstructed by the wire loop. A method for installing the dedusting unit to protect a laser optical element in a gas laser is also provided.

Abstract: The invention provides a discharge electrodes connecting structure for a laser apparatus in which a thickness of the return plate is set to be within an optimum range, and a laser apparatus employing the same. Accordingly, a laser apparatus is provided with a laser chamber (2) sealing a laser gas, a pair of anode (5A) and cathode (5B) provided within the laser chamber in an opposing manner, generating a discharge so as to excite a laser gas flowing therebetween and oscillating a laser beam, a conductive anode base (6) holding the anode, an insulative cathode base (8) holding the cathode, and a return plate (9) electrically connecting the anode base to the laser chamber so as to supply a current to the anode. A thickness (t) of the return plate is set to be equal to or more than 100 &mgr;m and equal to or less than 500 &mgr;m, and the return plate is arranged substantially in parallel to a gas flow of the laser gas flowing between the discharge electrodes.

Abstract: The present invention provides an excimer laser capable of producing a high quality pulsed laser beam at pulse rates of about 4,000 Hz at pulse energies of about 5 mJ or greater. A preferred embodiment is an ArF excimer laser specifically designed as a light source for integrated circuit lithography. An improved wavemeter with special software monitors output beam parameters and controls a very fast PZT driven tuning mirror and the pulse power charging voltage to maintain wavelength and pulse energy within desired limits. In a preferred embodiment two fan motors drive a single tangential fan which provides sufficient gas flow to clear discharge debris from the discharge region during the approximately 0.25 milliseconds between pulses.