Abstract: Methods and systems capable of measuring gas temperatures utilizing plasma discharges. Such a method performs a measurement of a temperature of a gas by generating a probing nanosecond plasma pulse in the gas, and then using an optical emission spectroscopy technique to measure the temperature of the gas by processing a light emission signal excited by the probing nanosecond plasma pulse.

Abstract: Aluminum oxide provides, at a thickness of 5 mm, an internal transmittance of 90% or higher for light at a wavelength of 193 nm.

Abstract: Disclosed is a laser discharge chamber in which useful lifetime is extended by local electrical tuning using one or a combination of design of the chamber internal geometry, placement and distribution of components within the chamber such as electrodes, current returns, and capacitors, and selective electrical isolation of portions of the components.

Abstract: Disclosed is a low pressure wire ion plasma discharge source including an elongated ionization chamber housing at least two parallel anode wires extending longitudinally within the ionization chamber. A first of the at least two anode wires is connected to a DC voltage supply and a second of the at least two anode wires is connected to a pulsed voltage supply.

Abstract: A slab laser includes first and second slabs defining an ionizing chamber intermediate the first slab and the second slab. A Radio Frequency Power Amplifier (RFPA) generates pulses to the ionizing chamber. The laser has a viewing window with access to the ionizing chamber and an optical sensor mounted to access the ionizing chamber through the viewing window. A controller is in communication with the optical sensor, and varies RFPA pulse power in response to the detection of glowing plasma by the optical sensor.

Abstract: An RF powered CO2 gas-discharge laser includes discharge electrodes and a lasing gas mixture between the electrode. The lasing gas mixture is ionized when the RF power is applied to the electrodes and laser action is initiated when the RF power has been applied for a duration sufficient to ignite a discharge in the lasing gas mixture. The gas mixture is pre-ionized by periodically applying the RF power to the electrodes for a predetermined period during which ignition of a discharge is not expected to occur. RF power reflected back from the electrodes is monitored. If the monitored power falls below a predetermined level indicative of the imminent onset of laser action before the predetermined duration has elapsed, application of the RF power to the electrodes is terminated to prevent the laser action from occurring.

Abstract: Arcing is minimized in a discharge chamber of a gas laser system by utilizing an electrode which comprises a surface portion capable of functioning as one of an anode and a cathode in order to energize a gas mixture in a discharge chamber of the gas discharge laser system, a shoulder portion being positioned on either side of the surface portion and being exposed to the gas mixture, and a coating layer made of electrically insulating material, wherein the coating layer is attached to the shoulder portion by a cold spraying method.

Abstract: Local magnetic field strength in a trapped ion atomic clock is measured in real time, with high accuracy and without degrading clock performance, and the measurement is used to compensate for ambient magnetic field perturbations. First and second isotopes of an element are co-located within the linear ion trap. The first isotope has a resonant microwave transition between two hyperfine energy states, and the second isotope has a resonant Zeeman transition. Optical sources emit ultraviolet light that optically pump both isotopes. A microwave radiation source simultaneously emits microwave fields resonant with the first isotope's clock transition and the second isotope's Zeeman transition, and an optical detector measures the fluorescence from optically pumping both isotopes.

Abstract: A method and system for maintaining an item of equipment supports the provision of predictive maintenance in a manner which eliminates or reduces downtime of the equipment. The method includes tracking performance data on the equipment or a particular component of the equipment. At least one required maintenance activity is predicted based upon the performance data with respect to a defined performance standard. Performance of the required maintenance activity is scheduled at a defined respective time based upon the prediction.

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

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 corona-discharge type, preionizer assembly for a gas discharge laser is disclosed. The assembly may include an electrode and a hollow, dielectric tube that defines a tube bore. In one aspect, the electrode may include a first elongated 0o conductive member having a first end disposed in the bore of the tube. In addition, the electrode may include a second elongated conductive member having a first end disposed in the bore and spaced from the first end of the first conductive member. For the assembly, the first and second conductive members may be held at a same voltage potential.

Abstract: The object of the invention in an arrangement for generating extreme ultraviolet radiation based on an electrically operated gas discharge is to reduce the time required for charging the electrodes by reducing the inductance of the discharge circuit. A high-voltage power supply connected to the electrodes which are constructed as disk electrodes and are rotatably mounted has a capacitor battery comprising capacitor elements which are arranged along a ring concentric to the axis of rotation of the electrodes with a ring plane directed parallel to the disk surface. Electrical connections are guided to the disk surfaces from the capacitor elements along a ring concentric to the axis of rotation.

Abstract: A laser waveguide, where the laser waveguide can be formed by electrodes and at least one sidewall in a manner allowing a more compact structure than previously provided. Protrusions in the electrodes allow easier laser starts, and sectional sidewall(s) allow easier fabrication of sidewall(s), decreasing manufacturing costs.

Abstract: A method and system for maintaining an item of equipment supports the provision of predictive maintenance in a manner which eliminates or reduces downtime of the equipment. The method includes tracking performance data on the equipment or a particular component of the equipment. At least one required maintenance activity is predicted based upon the performance data with respect to a defined performance standard. Performance of the required maintenance activity is scheduled at a defined respective time based upon the prediction.

Abstract: A laser waveguide, where the laser waveguide can be formed by electrodes and at least one sidewall in a manner allowing a more compact structure than previously provided. Protrusions in the electrodes allow easier laser starts, and sectional sidewall(s) allow easier fabrication of sidewall(s), decreasing manufacturing costs.

Abstract: A waveguide gas laser includes an enclosure filled with a lasing gas. A ceramic block is provided with one or more waveguide channels. At least one of the waveguide channels includes an open region which is in fluid communication with a waveguide channel. Lasing gas in the enclosure fills the waveguide channels and the lateral extension. An electric field is applied across the lateral extension of the waveguide channel while simultaneously applying a smaller electric field across the waveguide channel. The electric field across the lateral extension ignites a discharge in the lateral extension that spreads into the lasing gas in the waveguide channel. The electric field across the waveguide channel is sufficient to sustain the discharge in the lasing in the waveguide channel.

Abstract: Precise timing control can be obtained for a gas discharge laser, such as an excimer or molecular fluorine laser, using a timed trigger ionization. Instead of using a standard approach to control the timing of the emission or amplification of an optical pulse using the discharge of the main electrodes, the timing of which can only be controlled to within about 10 ns, a trigger ionization pulse applied subsequent to the charging of the main electrodes can be used to control the timing of the discharge, thereby decreasing the timing variations to about 1 ns. Since ionization of the laser gas can consume relatively small amounts of energy, such a circuit can be based on a fast, high-voltage, solid state switch that is virtually free of jitter. Trigger ionization also can be used to synchronize the timing of dual chambers in a MOPA configuration. In one such approach, ionization trigger can include at least a portion of the optical pulse from the oscillator in a MOPA configuration.

Abstract: A method and apparatus is provided for stabilizing output beam parameters of a gas discharge laser by maintaining a molecular fluorine component of the laser gas mixture at a predetermined partial pressure using a gas supply unit and a processor. The molecular fluorine is provided at an initial partial pressure and is subject to depletion within the laser discharge chamber. Injections of gas including molecular fluorine are performed each to increase the partial pressure of molecular fluorine by a selected amount in the laser chamber preferably less than 0.2 mbar per injection, or 7% of an amount of F2 already within the laser chamber. A number of successive injections may be performed at selected intervals to maintain the constituent gas substantially at the initial partial pressure for maintaining stable output beam parameters.

Abstract: A pre-ionizing arrangement for a gas laser includes two ceramic-jacketed ionizer electrodes extending into an enclosure including spaced-apart slab electrodes of the laser and a lasing gas at reduced pressure. RF power is applied to the dielectric-jacketed ionizer electrodes creating a gas discharge between the dielectric-jacketed ionizer electrodes. This discharge provides ions in the laser gas. The presence of these ions in the lasing gas facilitates ignition of a gas discharge between the slab electrodes for energizing the laser.

Abstract: A novel and inexpensive excitation circuit based on a single switch and a single source drives helium-free TEA CO2 lasers, mini to conventional types, providing low divergent output. By varying the partial pressure of either CO2 or N2, the duration (FWHM) and the peak power of the laser pulse (for a system with active volume about 70 cc) is made to vary by a factor of about 7 and about 5 respectively. The fact that expensive and scarce helium is not a constituent of the laser gas mixture makes it an ideal system for high repetition rate operation as the gas re-circulatory loop consisting of the heat exchanger and the catalytic re-converter, a mandatory requirement for conventional systems to recycle helium gas, can be readily dispensed with here. This laser can be used wherever a TEA CO2 laser with conventional gas mixture containing helium is used.

Abstract: A preionization device for a gas laser includes an internal preionization electrode having a dielectric housing around it such that the preionization device is of corona type. The internal electrode connects to advantageous electrical circuitry, preferably external to the discharge chamber via a conductive feedthrough. The circuitry reduces the voltage across the dielectric tube of the preionization unit to reduce over-flashing at tube ends and oscillations due to residual energies stored in the dielectric. A semi-transparent mesh electrode between the preionization unit and the discharge area prevents field distortions and discharge instabilities.

Abstract: The present invention relates to an excimer laser comprising a charging circuit including a parallel connection of a storage capacitor (CB) with a series connection of a reoscillation inductance (LB), a charging inductance (LL) and a firing device (Z) for firing the excimer laser, wherein the storage capacitor (CB) has at least a terminal for connecting a power supply (UL), a peaking capacitor (CP) connected in parallel with the charging inductance (LL), a discharge path including two opposed electrodes (E1, E2), connected in parallel with the peaking capacitor (CP), and a driving device for driving the firing device (Z), wherein the firing device (Z) is formed as a MOSFET array. The invention also relates to a corresponding method of operating such an excimer laser.

Abstract: The present invention is a device for avoiding sliding discharges in pre-ionization in a gas laser with corona discharge. The invention uses a pair of main electrodes provided in a closed gas discharge volume, and at least one pair of corona electrodes which are arranged in the immediate vicinity of the pair of main electrodes. The individual electrodes, which include a tube-like sheathing of dielectric material, are designed to be open on both ends and contain an electrically conducting rod, or core, introduced into the interior and projecting beyond the sheathing. The invention is distinguished by the provision that the material selection, the shaping of various elements associated with the gas discharge volume, or a combination of material selection and shaping is made in such a way that a specific capacitance per unit area is provided in the surface region on both ends of the sheathing is lower than the capacitance in the central region of the sheathing between its both ends.

Abstract: A device for use with a repetitively pulsed gas laser provides self-initiated UV preliminary ionization of the active volume of a laser, which has extended high-voltage and grounded electrodes disposed parallel to one another, to which peaking capacitors distributed along the length of the electrodes are connected in a low-inductance manner. The low-voltage contacts of the peaking capacitors are either connected directly to the grounded electrode or, if this connection is interrupted, dielectric plates are inserted that are disposed either on one side or on both sides of the grounded electrode. If the capacitors are charged rapidly, a surface discharge which effects UV pre-ionization of the volume of the main discharge and is uniformly distributed over the whole surface of the dielectric plates is produced on the surface of the dielectric plates.

Abstract: A corona preionization electrode unit for use in gas laser apparatus, wherein the electric field for corona discharge is concentrated, and ultraviolet radiation is not blocked, and further the laser gas stream is not obstructed, thereby allowing efficient, stable and uniform corona preionization. The corona preionization electrode unit is disposed in a gas laser apparatus together with a pair of main discharge electrodes for ionizing and exciting a laser gas. The corona preionization electrode unit includes a first electrode covered with a dielectric material and a second electrode placed in contact with the outer surface of the dielectric material around the first electrode. The corona preionization electrode unit is positioned in the vicinity of either one of the main discharge electrodes. The second electrode is a plate-shaped member having a straight edge contacting at least the outer surface of the dielectric material.

Abstract: A preionization device for a gas laser comprises an internal preionization electrode having a dielectric housing around it and an external preionization electrode displaced from the dielectric housing by a small gap. The dielectric housing includes two cylindrical regions of differing outer radii of curvature. An open end of the housing has a larger radius of curvature than the other end which is closed. The internal electrode connects to circuitry external to the discharge chamber via a conductive feedthrough which penetrates through the housing. The external circuitry prevents voltage oscillations caused by residual energy stored as capacitance in the dielectric housing. The external preionization electrode, which is connected electrically to one of the main discharge electrodes, is formed to shield the internal preionization electrode from the other main discharge electrode to prevent arcing therebetween.

Abstract: An ArF excimer laser device and a fluoride laser device for exposure which is structured so that primary current that infuses energy from a magnetic pulse compression circuit to discharge electrodes via a peaking capacitor overlaps secondary current that infuses energy from the capacitor in the final stage of the magnetic pulse compression circuit to the discharge electrodes, the oscillation cycle of the secondary current is set longer than the oscillation cycle of the primary current, and a pulse of laser oscillation operation is effected by the initial half-cycle of the discharge oscillation current waveform that reverses the polarity of the primary current being overlapped by the secondary current and by at least two half-cycles continuing thereafter, as a result of which a high repetition rate, pulse stretch, line-narrowed ArF excimer laser device and fluorine laser device can be implemented at repetition rate exceeding 2 kHz.

Abstract: A preionization device for a gas laser comprises an internal preionization electrode having a dielectric housing around it and an external preionization electrode displaced from the dielectric housing by a small gap. The dielectric housing includes two cylindrical regions of differing outer radii of curvature. An open end of the housing has a larger radius of curvature than the other end which is closed. The internal electrode connects to circuitry external to the discharge chamber via a conductive feedthrough which penetrates through the housing. The external circuitry prevents voltage oscillations caused by residual energy stored as capacitance in the dielectric housing. The external preionization electrode, which is connected electrically to one of the main discharge electrodes, is formed to shield the internal preionization electrode from the other main discharge electrode to prevent arcing therebetween.

Abstract: In a preionization discharge circuit 10, when a switch SW14 is turned on, an electric current i10 from a constant current source 13 flows through a loop of a coil L12, en electrode 11A and the switch SW14. When it is assumed that an inductance of the coil L12 is L (H) and the current i10 flowing through the coil L12 is I (A), energy EL of (1/2)·L·I{circumflex over ( )}2 is accumulated in the coil 12. Meanwhile, in a preionization discharge control section 40, a preionization discharge timing signal (namely, a corona emission timing signal) Ydt is output to the switch SW14 after lapse of a time ty (=Tds−tyd) after a pulse oscillation synchronizing signal TRL is received so that preionization discharge is caused earlier by a preset time tyd than the preionization discharge timing signal Ydt.

Abstract: Injection efficiency is greatly improved by chemically bonding an organic light emission molecule to an electrode, so as to realize a high efficiency light emission type of flat panel display and a high efficiency laser device, and realize a light emission type of flat panel display and a laser device which have higher performance than conventional organic light emission molecular devices.

Abstract: The amount of pre-ionization by the pre-ionization electrode provided on the gas outflow side of the main discharge space, out of at least one pair of pre-ionization electrodes, is adjusted so as to attain the desired beam profile. As a result, the pre-ionization intensity of the laser gas remaining on the gas outflow side of the main discharge space is made lower than the pre-ionization intensity of the laser gas flowing into the main discharge space. In other words, the intensity of the laser light on the gas outflow side of the main discharge space is made weaker than the intensity of the laser light in the center of the main discharge space. Accordingly, the location of the maximum light intensity of the beam profile does not deviate from the center of the discharge width.

Abstract: To reduce the cross-sectional area of a discharge circuit loop in the excitation circuit of a gas laser device that discharges ultraviolet rays, thereby reducing the inductance and enhancing the laser oscillation efficiency, the gas laser device is provided with a laser chamber (1) in which laser gas is sealed and which has a circulation means that circulates the laser gas within the chamber, a pair of main discharge electrodes (3, 4) disposed at a prescribed separation within said laser chamber (1), a discharge circuit having peaking capacitors (C3) that are connected in parallel with the pair of main discharge electrodes (3, 4,) and a preionization unit (15) in which a first electrode (9) and a second electrode (7) are disposed facing each other with a dielectric (8) interposed between them, the preionization unit (15) being disposed running along each side of one of the main discharge electrodes (4), that one of the main discharge electrodes (4) and the peaking capacitors (C3) being connected via a conduct

Abstract: A method and device for providing power to a load are disclosed. A beam of free electrons is directed from a free-electron source, such as an electron gun, into an enclosing conductive surface. The free-electron source includes a cathode, which is maintained at a negative voltage with respect to the enclosing conductive surface. A region around the free-electron source is maintained in a vacuum. The system is configured to switch over a time period between two configurations. In the first configuration, the enclosing conductive surface is isolated from a ground. In the second configuration, the enclosing conductive surface is in electrical communication with the ground. Capacitive energy is discharged from the enclosing conductive surface when in the second configuration with an electrical circuit arrangement and provided to the load.

Abstract: An excimer or molecular fluorine laser includes one or more sliding surface discharge preionization units each including an elongated preionization electrode spaced from one or more associated preionization electrodes by an elongated dielectric within the discharge chamber. The dielectric includes a sliding discharge surface at a long axis, or side, surface of its cross-section substantially facing the discharge volume of the laser. A portion of each of the elongated and associated preionization electrodes conductively contacts a surface of the dielectric portion preferably at a cross-sectional short axis, or top or bottom, side of the dielectric. A significant area of the surface of at least one, and preferably both, of the elongated and associated electrodes contacts the corresponding surface of the dielectric such that the contact area is substantially larger than the area of the sliding discharge surface.

Abstract: The present invention provides a novel and improved technique for achieving a combined RF-DC gas discharge in the optical cavity of the gas laser. The combination of the fast pre-ionization with the transverse RF discharge and the high power excitation with the highly-efficient longitudinal DC discharge allows for a high-speed laser gain modulation of the active medium of the high-power gas laser. At the same time, the all-metal electrode system allows for a very compact, reliable and low cost design of the gas laser.

Abstract: An emission timing control apparatus for a pulsed laser including a magnetic pulse compression circuit having a switching section for carrying out a switching operation to connect and disconnect a charging power source to and from the magnetic pulse compression circuit. The pulsed laser executes pulsed laser oscillation at a prescribed repetition frequency by turning on the switching section with a pulse oscillation synchronizing signal having the prescribed repetition frequency received from a semiconductor exposure apparatus, in which the emission timing control apparatus includes a reference delay time setting section for setting a prescribed reference delay time, and delay section for delaying a pulse oscillation synchronizing signal received from the semiconductor exposure apparatus by the time difference &tgr; calculated in the delay time calculating section and outputting to the switching section.

Abstract: The present invention provides a novel metal-vapor pulsed laser capable of being manufactured without using a large-sized laser tube or an expensive discharging circuit. The output and the efficiency of the laser can be improved economically and easily. The laser includes a laser tube having a cathode and an anode. A discharging circuit induces an electric discharge in the laser tube. A grid electrode is mounted close to the cathode of the laser tube. A preliminary discharge is produced between the grid electrode and the cathode to thereby induce a main discharge.

Abstract: A pulser with solid dielectrics including a pulse compressor and pulse transformer apparatus, which is able to produce short bursts of electrical energy at high voltage utilizing a coaxial structure. Both the transformer and the compressor utilize ferromagnetic cores having an inner and an outer diameter, and isolating members of similar geometry. The cores and ceramic members are held in place using conducting plates and bus bars. The overall structure of the compressor and the transformer is built around a central axis.

Abstract: An extremely compact soft x-ray and/or extreme ultraviolet laser is disclosed that can be repetitively fired within short time intervals. The laser generates a plasma within a capillary (3) by flowing through the capillary (3) a fast high current pulse generated by a very compact liquid dielectric (1) transmission line (9) geometry.

Abstract: A new cartridge excimer laser system and method for generating an excimer laser beam using the system are provided. The system utilizes a cartridge (10) which contains a halogen-noble gas mixture (19), electrodes (50, 60) having external electrical connections (30, 40), and assembly (20) for transmitting a laser beam output (400), and an external gas port (90). The cartridge (10) fits onto a receptacle (100) located within a receiving compartment (200) of the laser base (300) of the new system. The cartridge (10) is easily replaced by the system operator and is refurbished by the manufacturer when the gas mixture (19) therein is exhausted.

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz or greater. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control. These improvements include an increased capacity high voltage power supply with a voltage bleed-down circuit for precise voltage trimming, an improved commutation module that generates a high voltage pulse from the capacitors charged by the high voltage power supply and amplifies the pulse voltage 23 times with a very fast voltage transformer having a secondary winding consisting of a single four-segment stainless steel rod.

Abstract: A gas laser includes an enclosure forming a first chamber, a second chamber and a lasing chamber which communicates through a first opening to the first chamber and through a second opening to the second chamber. The lasing chamber has a pair of reflectors defining a Fabry-Perot cavity. Separate inlets enable different gases to be introduced into the first and second chambers. A first cathode within the first chamber is provided to produce positive ions which travel into the lasing chamber and a second cathode of a pin-hollow type within the second chamber is provided to produce negative ions which travel into the lasing chamber. A third inlet introduces a molecular gas into the lasing chamber, where the molecular gas becomes excited by the positive and negative ions and emits light which lases in the Fabry-Perot cavity.

Abstract: The description relates to a discharge device (1) for pulsed gas lasers in which there are laser electrodes (8, 9) in the space (15) between which discharges with intense UV emission are produced by an arrangement on at least one side, by which the space (15) between the laser electrodes (8, 9) is pre-ionized. Essentially in the invention, the arrangement (2, 3, 4) includes at least one rod electrode (2) which is surrounded by an insulating, preferably ceramic, material (4) and has a conductive contact (5) with the surface (6) of the insulating ceramic material (4), and on this surface (6) there is at least one counter-electrode (7) spaced from the rod electrode (2), the counter-electrode (7) being conductively connected to one of the laser electrodes (8), so that sliding discharge tracks or paths (13) are formed between the at least one rod electrode (2) and the counter-electrode (7).

Abstract: A new cartridge excimer laser system and method for generating an excimer laser beam using the system are provided. The system utilizes a cartridge (10) which contains a halogen-noble gas mixture (19), electrodes (50, 60) having external electrical connections (30, 40), and assembly (20) for transmitting a laser beam output (400), and an external gas port (90). The cartridge (10) fits onto a receptacle (100) located within a receiving compartment (200) of the laser base (300) of the new system. The cartridge (10) is easily replaced by the system operator and is refurbished by the manufacturer when the gas mixture (19) therein is exhausted.

Abstract: A pre-ionizing system in which the pre-ionizer elements are integral with the cathode insulating plate is provided. The cathode insulating plate includes a recessed region machined into the front surface into which the cathode fits, lying substantially flush with the insulator front surface. The back surface of the insulating plate contains a pair of slots running parallel to the long axis of the cathode. The pre-ionizing rods are located within these slots, the slots having sufficient depth to locate the rods approximately adjacent to the cathode. By maintaining the rods at ground, a capacitor is formed in which the insulating plate material between the rod and the cathode acts as the dielectric material of the capacitor. When a voltage pulse is applied, a capacitive corona discharge is formed which pre-ionizes the gases in the region near the cathode.

Abstract: The invention relate to a laser oscillator containing at least one pair of main electrodes within a laser tube. In accordance with the first invention, a downstream one of the main electrodes provided within the laser tube which is located downstream, as viewed in the direction of flow of a laser gas, is substantially L-shaped, with its distal end being supported to extend in a direction to intersect with the axial direction of the laser tube. This improves the oscillation efficiency in exciting the laser radiation as compared with the prior art. According to the second aspect of the invention, a pair of ring-shaped pre-ionization electrodes are disposed upstream of the main electrodes, and there is provided a pre-ionization power supply which applies a high voltage, which may be a pulse wave or an alternating voltage, across the pair of pre-ionization electrodes.

Abstract: An excimer laser chamber capable of arc-free operation at repetitive pulse rates of 1 kHz or greater is provided. The chamber balances the electrode design criteria required to produce a well-defined discharge channel with the flow design criteria required to achieve high clearing rates at comparatively high blower efficiency. A ceramic insulator located on either side of the cathode/pre-ionizer assembly enhances the flow of gas through the discharge region by reducing the turbulence in the electrode region. A series of specifically designed flow vanes further enhance the gas flow. The gas exiting the blower fan is guided into the discharge region with one vane. The anode support bar is extended downwardly, thus improving the efficiency of the tangential blower and also minimizing the amount of gas bypassing the discharge region. A pair of vanes downstream from the discharge region smoothly direct the heated gas towards the heat exchanger.

Abstract: A first object is to stabilize output of laser light. In order to achieve the first object, if it is detected by an output detection means (15) that the output (E) of laser light (La) has departed from a target value, whilst maintaining the voltage of a power source (17) at a fixed value or in a fixed range, the amount of laser gas supplied to a laser chamber (4) is controlled such that the output (E) of laser light becomes the target value. A second object is to reduce the wear of the pre-ionization electrodes and to prevent drop in output of laser light. The second object is achieved as follows. Specifically, the pulse current discharged from primary capacitor (C1) is stepped up in voltage by a pulse transformer and is charged onto a secondary capacitor (C2).

Abstract: The present invention provides a reliable modular production quality excimer laser capable of producing 10 mJ laser pulses in the range of 1000 Hz to 2000 Hz or greater. Replaceable modules include a laser chamber; a pulse power system comprised of three modules; an optical resonator comprised of a line narrowing module and an output coupler module; a wavemeter module, an electrical control module, a cooling water module and a gas control module. Important improvements have been provided in the pulse power unit to produce faster rise time and improved pulse energy control. These improvements include an increased capacity high voltage power supply with a voltage bleed-down circuit for precise voltage trimming, an improved communication module that generates a high voltage pulse from the capacitors charged by the high voltage power supply and amplifies the pulse voltage 23 times with a very fast voltage transformer having a secondary winding consisting of a single four-segment stainless steel rod.