Abstract: A low inductance, hermetically sealed, RF shielded feed-through is provided for exciting low impedance discharges associated with high power CO2 slab lasers. The feed-through mechanically obtains RF contact, preferably, at the center of the length of the electrodes that are inserted within the long laser housing, thereby making it easier to obtain a uniform electric field distribution along the length of the electrodes.

Abstract: In a CO2 laser a pre-ionizer is assembled in a flange configured to be attached to a laser-gas enclosure of the laser over an aperture in a wall of the enclosure. An aperture in the base of the flange is aligned over the aperture in the enclosure wall. The aperture in the pre-ionizer flange is covered by a ceramic membrane. A disc electrode is in contact with the ceramic membrane on a side of the membrane outside of the laser-gas enclosure. An RF potential applied to the disc electrode creates a corona discharge on the side of the ceramic membrane inside the enclosure. The corona discharge ionizes laser gas in the enclosure before RF power is applied to electrodes of the slab laser.

Abstract: A method/apparatus may comprise a seed laser oscillator producing an output which may comprise: a first gas discharge excimer or molecular fluorine laser chamber; a line narrowing module within a first oscillator cavity; a laser amplification stage receiving the output of the seed laser oscillator which may comprise: a ring power amplification stage; a coherence busting mechanism intermediate the seed laser oscillator and the ring power amplification stage which may comprise a beam splitter separating the seed laser output into a main beam and a beam entering an optical delay path which may have a delay length longer than the coherence length of a pulse in the seed laser output and may have a beam angular offset mechanism offsetting a delayed beam and the main beam.

Abstract: A system of controlling a wavelength of a laser beam is provided. The system comprises a stage for supporting a wafer, an optical convergence unit for emitting the laser beam moving in an optical path toward the stage, and a specific wavelength detecting sensor. The specific wavelength detecting sensor is disposed between the optical convergence unit and the stage. It includes a laser beam absorbing structural body for absorbing a specific wavelength of the laser beam emitting toward the stage. A wavelength controlling unit for selectively controlling the wavelength of the laser beam is also provided.

Abstract: A system and method for collecting radiation, which may be used in a lithography illumination system. The system comprises a first surface shaped to reflect radiation in a first hemisphere of a source to illuminate in a second hemisphere of the source; and a second surface shaped to reflect radiation in the second hemisphere of the source to an output plane.

Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.

Abstract: The invention relates to an optical delay module for lengthening the propagation path of a light beam comprises a first spherical mirror and a second spherical mirror, the first spherical mirror and the second spherical mirror having equal radii of curvature, the first and the second mirror being arranged on a common axis of symmetry with concave sides of the first and second mirrors being situated opposite one another at a distance from one another which corresponds to the radii of curvature of the first and second mirrors. The module also includes a coupling-in area for coupling the light beam into a space between the first and second mirrors and a coupling-out area for coupling the light beam out of the space between the first and second mirrors.

Abstract: An apparatus and method is disclosed which may comprise a laser produced plasma EUV system which may comprise a drive laser producing a drive laser beam; a drive laser beam first path having a first axis; a drive laser redirecting mechanism transferring the drive laser beam from the first path to a second path, the second path having a second axis; an EUV collector optical element having a centrally located aperture; and a focusing mirror in the second path and positioned within the aperture and focusing the drive laser beam onto a plasma initiation site located along the second axis. The apparatus and method may comprise the drive laser beam is produced by a drive laser having a wavelength such that focusing on an EUV target droplet of less than about 100 ?m at an effective plasma producing energy if not practical in the constraints of the geometries involved utilizing a focusing lens. The drive laser may comprise a CO2 laser. The drive laser redirecting mechanism may comprise a mirror.

Abstract: A laser device is provided. The laser device includes a laser tube, oscillator circuitry, and a compensating reactive component that is arranged in parallel with the laser tube.

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 laser ice etching system (7) includes a laser (11) for producing a laser beam, a laser aiming system (13) adapted to aim and direct a laser beam produced by the laser (11) onto forming ice cubes and a controller (9) operatively coupled to the laser (11) and the laser aiming system (13). The controller (9) provides commands to the laser (11) to produce the laser beam and commands to the laser aiming system (13) to aim and direct the laser beam onto the forming ice cubes. The laser ice etching system (7) is positioned adjacent to a vertical cold plate (3) of an ice making machine (1) and forms an image in the center of an ice cube by aiming and directing the laser beam in a predetermined pattern over a portion of the ice cube.

Abstract: Laser systems have a line-narrowed master oscillator and a power oscillator for amplifying the output of the master oscillator. The power oscillator includes optical arrangements for limiting the bandwidth of radiation that can be amplified. The limited amplification bandwidth of the power oscillator is relatively broad compared to that of the output of the master oscillator, but narrower than would be the case without the bandwidth limiting arrangements. The bandwidth narrowing arrangements of the power oscillator function primarily to restrict the bandwidth of amplified spontaneous emission generated by the power oscillator.

Abstract: A system is used to substantially reduce divergence of a beam traveling between master and power oscillators, for example in a laser beam source. The system comprises the first and second oscillators and a beam conditioning device. The first oscillator is configured to generate a radiation beam. The beam conditioning device is configured to stabilize a position, a direction, a size, or a divergence of the radiation beam to produce a conditioned beam. The second oscillator configured to amplify the conditioned beam to produce an amplified beam.

Abstract: A method/apparatus may comprise operating a line narrowed pulsed excimer or molecular fluorine gas discharge laser system by using a seed laser oscillator to produce an output which may comprise a first gas discharge excimer or molecular fluorine laser chamber; a line narrowing module; a laser amplification stage which may comprise a ring power amplification stage; the method of operation may the steps of: selecting a differential timing between an electrical discharge between a pair of electrodes in the first laser chamber and in the second laser chamber which at the same time keeps ASE below a selected limit and the pulse energy of the laser system output light beam of pulses essentially constant.

Abstract: An apparatus and method is disclosed which may comprise a laser produced plasma EUV system which may comprise a drive laser producing a drive laser beam; a drive laser beam first path having a first axis; a drive laser redirecting mechanism transferring the drive laser beam from the first path to a second path, the second path having a second axis; an EUV collector optical element having a centrally located aperture; and a focusing mirror in the second path and positioned within the aperture and focusing the drive laser beam onto a plasma initiation site located along the second axis. The apparatus and method may comprise the drive laser beam is produced by a drive laser having a wavelength such that focusing on an EUV target droplet of less than about 100 ?m at an effective plasma producing energy if not practical in the constraints of the geometries involved utilizing a focusing lens. The drive laser may comprise a CO2 laser. The drive laser redirecting mechanism may comprise a mirror.

Abstract: A beam mixer for increasing intensity symmetry along a selected axis of a beam (wherein the beam extends from a first edge to a second edge along the axis) is disclosed and may include a plurality of mirrors establishing a spatially inverting path. For the beam mixer, the inverting path may have a beginning and an end and may be characterized in that a part of the beam near the first beam edge at the beginning of the path translates to the second beam edge at the end of the path. For this aspect, the beam mixer may further include an optic dividing the beam into first and second beam portions, the optic placing the first portion onto the inverting path and recombining the first and second portions onto a common path after the first portion has traveled along the inverting path thereby mixing the beam.

Abstract: Systems and methods for efficiently operating a gas discharge excimer laser are disclosed. The excimer laser may include a chamber containing laser gases, first and second electrodes within the chamber, and a plurality of reflective elements defining an optical resonant cavity. The method may include setting the laser gases to a first pressure; after setting the gases to the first pressure, applying a first voltage to the electrodes, thereby propagating a laser beam in the optical resonant cavity; measuring energy of the beam; adjusting the first voltage until the energy of the beam is substantially equal to a target pulse energy; operating the laser for an amount of time; after the amount of time, measuring energy of the beam; and changing the pressure of the gases to a second pressure different from the first pressure.

Abstract: A beam delivery system of a projection exposure system comprises a laser generating a beam of laser light from a plurality of longitudinal laser modes in a cavity, wherein light generated by a single longitudinal laser mode has an average line width ?lat, wherein the laser light of the beam has, at each of respective lateral positions of the beam, a second line width ?lat corresponding to lateral laser modes, and wherein the laser light of the beam has, when averaged over a whole cross section thereof, a line width ?b corresponding to plural lateral laser modes, and wherein ?m<?lat<?b, and wherein an optical delay apparatus disposed in the beam provides an optical path difference ?l, wherein 0.8 · ? 0 2 ( 2 · ? ? ? ? l ) < ? ? ? l < 1.8 · ? 0 2 ( 2 · ? ? ? ? l ) , wherein ?0 is an average wavelength of the light of the first beam of laser light, and ??lat represents the second line width.

Abstract: An apparatus/method which may comprise a line narrowed pulsed excimer or molecular fluorine gas discharge laser system which may comprise a seed laser oscillator producing an output comprising a seed laser output light beam of pulses which may comprise a first gas discharge excimer or molecular fluorine laser chamber; a line narrowing module within a first oscillator cavity; a laser amplification stage containing an amplifying gain medium in a second gas discharge excimer or molecular fluorine laser chamber receiving the output of the seed laser oscillator and amplifying the output of the seed laser oscillator to form a laser system output comprising a laser system output light beam of pulses, which may comprise a ring power amplification stage; a seed injection mechanism.

Abstract: A line narrowing module includes an elliptical mirror, a diffraction grating disposed at a first focus of the mirror for separating an incident beam into different lines, and a laser beam dispersion and extraction unit. The laser beam dispersion and extraction unit disperses incident laser over the diffraction grating and selectively extract from the resulting lines a laser beam having a desired narrowed bandwidth. A light source that employs the line narrowing module also includes a laser oscillator for generating the beam, and a light returning unit that returns one fraction of the beam extracted from the laser oscillator back to the laser oscillator. Another fraction of the beam is extracted from the laser oscillator through a front window of the laser oscillator, and undergoes line narrowing in the module. The laser beam having the narrowed bandwidth is immediately output as the exposure light from the module.

Abstract: Laser systems have a line-narrowed master oscillator and a power oscillator for amplifying the output of the master oscillator. The power oscillator includes optical arrangements for limiting the bandwidth of radiation that can be amplified. The limited amplification bandwidth of the power oscillator is relatively broad compared to that of the output of the master oscillator, but narrower than would be the case without the bandwidth limiting arrangements. The bandwidth narrowing arrangements of the power oscillator function primarily to restrict the bandwidth of amplified spontaneous emission generated by the power oscillator.

Abstract: A gas discharge laser system producing a laser output pulse and a method of operating such a system is disclosed which may comprise a pulse stretcher which may comprise a laser output pulse optical delay initiating optic directing a portion of the laser output pulse along a laser system output pulse optical axis and diverting a portion of the output pulse into an optical delay having an optical delay path and which may comprise a plurality of confocal resonators in series aligned to deliver an output of the optical delay to the laser output pulse optical delay initiating optic; an optical axis alignment mechanism comprising an radial mirror positioning mechanism operable to position the output of the optical delay to the align with the portion of the laser output pulse transmitted along the optical axis of the portion of the laser system output pulse transmitted by the laser output pulse optical delay initiating optic.

Abstract: A novel laser cavity structure is disclosed which pertains to laser resonator geometries possessing circular symmetry, such as in the case of disk or spherical lasers. The disclosed invention utilizes a very-high finesse Bragg reflector (VHF-BR) thin film reflectors of many layer pairs of very small refractive index difference, the VHF-BR deposited on a surface of revolution, thereby forming an optical cavity. These dielectric reflectors are disposed in such a way as to allow selection of preferred low order modes and suppression of parasitic modes while allowing a high cavity Q factor for preferred modes. The invention disclosed, in its preferred embodiments, is seen as particularly useful in applications requiring high efficiency in the production and coupling of coherent radiation. This is accomplished in a cavity design that is relatively compact and economical. Of particular novelty is the combination of the disclosed cavity design with polymer multilayers.

Abstract: A power-combining system and method for generating a high-power coherent wavefront are generally described herein. Other embodiments may be described and claimed. The power-combining system comprises a combining-radiating assembly having a plurality of ports. Phase controllers generate signals with a predetermined phase shift for an associated one of the ports. Pluralities of coherent sources receive signals from an associated one of the phase controllers and to provide the signals to an associated port of the combining-radiating assembly with the predetermined phase shifts. Energy from the ports is coherently combined and radiated to provide a coherent high-power wavefront. In some embodiments, the combining-radiating assembly comprises a conductive patch having a plurality of ports spaced uniformly around the patch. In these embodiments, energy from the ports is coherently combined and radiated by the patch to provide the coherent high-power wavefront.

Abstract: A charging voltage Vosc applied to a main capacitor C0 disposed in an oscillating high-voltage pulse generator 12 of an oscillating laser 100 is subject to constant control such that a pulse energy Posc of the oscillating laser 100 becomes a lower limit energy Es0 or more of an amplification saturation region. And, a charging voltage Vamp applied to a main capacitor C0 disposed in an amplifying high-voltage pulse generator 32 of an amplifying laser 300 is controlled, and pulse energy Pamp of the amplifying laser 300 is determined as target energy Patgt. Thus, the pulse energy of a two-stage laser is controlled to stabilize the pulse energy.

Abstract: An integrated circuit lithography technique called spectral engineering by Applicants, for bandwidth control of an electric discharge laser. In a preferred process, a computer model is used to model lithographic parameters to determine a desired laser spectrum needed to produce a desired lithographic result. A fast responding tuning mechanism is then used to adjust center wavelength of laser pulses in a burst of pulses to achieve an integrated spectrum for the burst of pulses approximating the desired laser spectrum. The laser beam bandwidth is controlled to produce an effective beam spectrum having at least two spectral peaks in order to produce improved pattern resolution in photo resist film. Line narrowing equipment is provided having at least one piezoelectric drive and a fast bandwidth detection control system having a time response of less than about 2.0 millisecond.

Abstract: A two phase reactor includes a source of liquid reactant and a source of gas reactant. A chamber has an inlet coupled to the source of gas reactant and a flat jet nozzle coupled to the source of the liquid reactant.

Abstract: A narrow-band laser device for exposure apparatus that allows to reduce damage to, and to hence extend the life of, optical elements such as chamber windows, output coupling mirrors or the like. A ring resonator is provided in an amplification stage laser of the narrow-band laser device for exposure apparatus that comprises an oscillation stage laser and an amplification stage laser. An OC, a high reflection mirror and a high reflection mirror are arranged to be offset, for instance, relative to a longitudinal direction axis of discharge electrodes. As a result, the beam width of laser light injected through the OC of the amplification stage laser becomes wider as the beam shifts inside the ring resonator, in each round trip within the ring resonator. The energy density of laser light in the optical elements of the amplification stage laser becomes reduced thereby, thus prolonging the life of the optical elements.

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: The relative timing delay between channels of a discharge circuit can be adjusted through application of appropriate control voltages. A control voltage of relatively long duration and relatively small voltage, with respect to a common system pulse, can be applied to any channel in order to adjust the relative timing delay. This control voltage can be, for example, a magnetization pre-pulse voltage applied to an indictor for a channel in order to adjust a hold-off time. A synchronization control unit and feedback loop can be used to monitor the timing, such that the syncronization control unit can apply a control voltage when a delay change exceeds a timing adjustment threshold value, and can apply a pre-ionization voltage when the delay change is less than the adjustment threshold value. Using both a control voltage and a pre-ionization voltage provides for both coarse and fine adjustment of the delay.

Abstract: 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 pu

Abstract: Fluorine gas discharge laser electrodes and electrode systems that may comprise a plurality of current return tangs extending for less than the respective length of the second elongated gas discharge electrode. In addition electrodes may comprise a first discharge shaping magnet mounted in a first elongated gas discharge electrode and a second discharge shaping magnet mounted in a second elongated gas discharge electrode. Also is an electrode may comprise a crown straddling the centerline axis between the pair of side walls and the pair of end walls, comprising a first material, forming at least a portion of the discharge region of the electrode and a pair of elongated high erosion regions on either side of the crown comprising a second material with a relatively higher erosion rate during gas discharge than that of the first material.

Abstract: An excimer laser device capable of suppressing deterioration of optical elements provided in a laser chamber even if output energy per pulse is increased more than the conventional level, in which a width of a laser beam applied to the optical elements provided in the laser chamber is enlarged so as to reduce the energy density of the laser beam within such a range that a laser output of no less than a desired level is obtained.

Abstract: A gas discharge laser and method of operating same is disclosed which may comprise a gas discharge laser chamber support structure comprising a first support arm attached to a mounting table; a gas discharge laser chamber slideably engaging the first support arm; an first optical element sensitive to chamber vibration positioned at a first end of the laser chamber mounted on the mounting table; the laser chamber support structure being without connection to the first optical element. The apparatus and method may also comprise a second optical element sensitive to chamber vibration positioned at the second end of the laser chamber mounted on the mounting table; the laser chamber support structure being without connection to the second optical element. The first optical element may comprise a line narrowing optical arrangement and the second optical element comprising an output coupler.

Abstract: A Master Oscillator (MO)—Power Amplifier (PA) configuration (MOPA) can be used advantageously in an excimer laser system for micro-lithography applications, where semiconductor manufacturers demand powers of 40 W or more in order to support the throughput requirements of advanced lithography scanner systems. The timing of discharges in discharge chambers of the MO and PA can be precisely controlled using a common pulser to drive the respective chambers. The timing of the discharges further can be controlled through the timing of the pre-ionization in the chambers, or through control of the reset current in the final compression stages of the pulser. A common pulser, or separate pulser circuits, also can be actively controlled in time using a feedback loop, with precision timing being achieved through control of the pre-ionization in each individual discharge chamber. Yet another system provides for real-time compensation of time delay jitter of discharge pulses in the chambers.

Abstract: An integrated circuit lithography technique called spectral engineering by Applicants, for bandwidth control of an electric discharge laser. In a preferred process, a computer model is used to model lithographic parameters to determine a desired laser spectrum needed to produce a desired lithographic result. A fast responding tuning mechanism is then used to adjust center wavelength of laser pulses in a burst of pulses to achieve an integrated spectrum for the burst of pulses approximating the desired laser spectrum. The laser beam bandwidth is controlled to produce an effective beam spectrum having at least two spectral peaks in order to produce improved pattern resolution in photo resist film. Line narrowing equipment is provided having at least one piezoelectric drive and a fast bandwidth detection control system having a time response of less than about 2.0 millisecond.

Abstract: An infrared laser has a seed laser with an optical seed output. A pump amplifier receives the optical seed output and has an amplified output. A molecular gas laser receives the amplified output and has an infrared optical output.

Abstract: An electric discharge, narrow band gas laser with improvements in wavelength stability. Improvements result from reduced laser beam directional fluctuations or fast correction of those fluctuations. Applicant has discovered, using an extremely sensitive knife edge optical technique, that gas discharge laser windows in a trapezoidal configuration were causing slight wavelength perturbations when laser gas density varied during laser operation. The optical technique involves using test laser beam directed through the discharge region of the gas discharge laser, blocking a portion of the beam with a knife edge and measuring the non-blocked portion of the beam to monitor beam deflection. With this technique, Applicant can measure beams deflection with an accuracy of about 0.3 microradians and with a time response of about 1 microsecond.

Abstract: An excimer laser comprises a gas chamber, electrodes for creating rare gas/halide molecules that disassociate and produce optical emission, and reflective surfaces that form an optical resonant cavity. The excimer laser further comprises flow control surfaces that define gas flow paths and that control the flow of gas within the chamber. Preferably such flow control surfaces direct the gases away from the laser optics. More preferably, the flow control surfaces shield the path of the laser beam, at least in the proximity of the laser optics, from contaminants in the gases. Less contaminants yields less contamination of the laser optics. As a result, the laser device becomes more reliable and useful over longer periods of time. In addition, the laser gases are preferably exposed only to compatible materials that react with the laser gases to produce stable reaction products having a low vapor pressure, so as to reduce contamination of the gases and the optics.

Abstract: An excimer laser and a line-narrowing module capable of increasing and maximizing production yield in semiconductor manufacturing are disclosed. The line-narrowing module utilizes a beam expander that passes laser light, produced by and incident from a generator of the excimer laser and collimates the laser light in one direction. A diffraction grating receives the collimated laser light and diffracts the laser light and causes a traveling direction of the laser light to be separated according to an associated wavelength of the laser light. A multi-wavelength reflector located at a reflecting position on one side between the diffraction grating and the beam expander in order to re-enter the laser light having a multi-wavelength into the generator through the beam expander. The multi-wavelength reflector reflects the laser light consisting of a plurality of wavelengths among the laser light whose traveling direction is separated from the diffraction grating onto the beam expander.

Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.

Abstract: A Master Oscillator (MO)—Power Amplifier (PA) configuration (MOPA) can be used advantageously in an excimer laser system for micro-lithography applications, where semiconductor manufacturers demand powers of 40 W or more in order to support the throughput requirements of advanced lithography scanner systems. A MOPA-based laser system can provide both high pulse energies and high spectral purity. A MOPA system can utilize a multi-pass PA, as well as a special beam path capable of reducing the amount of ASE (Amplified Spontaneous Emission) and feedback to the MO. Lithography scanner optics are primarily fused silica, such that the peak pulse power must be kept low to avoid material compaction when a MOPA system is used with lithography applications. This conflict between the demand for high average power and the low peak power requirement of the pulsed excimer laser source can be resolved by using a novel beam path to generate a sufficiently long pulse length.

Abstract: A method and apparatus are disclosed for controlling the output of a two chamber gas discharge laser comprising an oscillator gas discharge laser and an amplifier gas discharge laser that may comprise establishing a multidimensional variable state space comprising a coordinate system having at least two coordinates, each coordinate comprising a selected variable representing an operating parameter of the oscillator or the amplifier; tracking a multidimensional operating point in the multidimensional variable state space according to the variation of the selected variables in either or both of the oscillator or the amplifier to determine the position of the multidimensional operating point in the multidimensional state space; determining from the position of the multidimensional operating point in the multidimensional operating space a region from a plurality of defined regions in the multidimensional operating space in which the multidimensional operating point is located and identifying the region.

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 laser oscillating apparatus includes a discharger for exciting a laser medium, a blower for blowing a laser gas and a laser gas path for connecting the discharger and the blower, and a laser oscillating apparatus characterized in that the blower includes a shaft portion provided with a blade wheel portion at a front end thereof, a driving portion for rotating the shaft portion, and a partition wall portion for separating the blade wheel portion and the driving portion, and a surface of the partition wall portion is provided with a metal layer dispersing precipitated polytetrafluoroethylene (PTFE).

Abstract: An excimer laser with a laser chamber containing a circulating laser gas containing fluorine and long-life, annealed, copper alloy electrodes. Electrode lifetime is increased by annealing them after the electrodes are machined. This annealing relieves the surface stress caused by the machining operation and reduces the exposed metallic grain boundary length per unit area on the surface of the electrodes, which provides substantial reduction in erosion caused by fluorine chemical attack. Annealing after machining also reduces the stress throughout the bulk of the electrode material. In preferred embodiments the anode is a copper-aluminum alloy and the cathode is a copper-zinc alloy.

Abstract: An optical pulse extender includes a delay loop formed by a plurality of mirrors and a graded reflectivity beamsplitter. The mirrors and the beamsplitter are configured and aligned such that a pulse to be broadened makes a predetermined number of round trips in the delay loop and is incident on a different zone of the beamsplitter after each round trip. The different zones of the beamsplitter have different reflection values and different transmission values. These values are selected such that the pulse extender delivers a plurality of temporally and spatially separated replica pulses each thereof having about the same energy. The delivered replica pulses together provide an extended pulse having a longer duration than the input pulse. The replica pulses may be passed through a beam homogenizer to spatially homogenize the temporal characteristics of the extended pulse.

Abstract: Improved temperature stabilization can be obtained for pulsed gas discharge laser systems, such as excimer laser systems, using information about the energy dissipation of the system. Temperature sensors have a limited response time, which can lead to undesirable instability in gas temperature. By determining the heat energy provided to the discharge chamber over sufficiently small periods of time, a system controller can account for rapid variations in the temperature of the laser gas. The temperature regulation controller can adjust a flow of cooling liquid into the discharge chamber to account for these rapid variations on a scale that is much shorter than the response time of the temperature sensors. For variations over longer periods of time, the temperature regulation controller can utilize an active heater in contact with the laser tube to heat the laser tube body, thereby uniformly heating the gas in the tube.

Abstract: Pulse parameters of a gas discharge laser system can be optimized and controlled for precision applications such as microlithography. Important laser pulse parameters typically vary in the beginning of a pulse burst, and the directionality of the output beam typically varies throughout the burst. In order to improve the performance of the laser system, the variation at the beginning of a pulse burst can be eliminated by extending the pulse pattern and shuttering the output during periods of significant parameter variation. A fast shutter such as an acousto-optical modulator can be used to prevent output during the burst transition processes. Elements such as acousto-optical cells also can be used in combination with a fast position sensor to steer the direction of the output beam, in order to adjust for variations in the direction of the beam between pulses in a burst.

Abstract: Apparatus/method providing bandwidth control in narrow band short pulse duration gas discharge laser output light pulse beam producing systems, producing a beam comprising pulses at selected pulse repetition races, e.g., comprising a dispersive bandwidth selection optic selecting at least one center wavelength for each pulse determined at least in part by the angle of incidence of the beam containing the respective pulse on the optic; a tuning mechanism operative to select at least one angle of incidence of the beam containing the respective pulse upon the optic; the tuning mechanism comprising a plurality of incidence angle selection elements each defining an angle of incidence for a different spatially separated but not temporally separated portion of the pulse to return from the optic a laser light pulse comprising a plurality of spatially separated but not temporally separated portions, each having one of at least two different selected center wavelengths.

Abstract: An apparatus and method for the production of polymeric films by a blown film process is disclosed. Polymeric films produced from crystallizable linear polymers are extruded through a die extruder, expanded by the injection of a gas inside the tubular film, cooled at the point of extrusion from the die, and further cooled at the point of maximal expansion or the frost line to produce a film having substantially enhanced optical characteristics.