Abstract: An excimer or molecular fluorine laser system includes a discharge chamber containing a gas mixture, multiple electrodes connected to a power supply circuit for energizing the gas mixture, a resonator for generating a laser beam, a processor, and means for monitoring an amplified spontaneous emission (ASE) signal of the laser, such as preferably an ASE detector. The processor receives a signal from the preferred ASE detector indicative of the ASE signal of the laser. Based on the signal from the ASE detector, the processor determines whether to initiate a responsive action for adjusting a parameter of the laser system.

Abstract: Method and system provide a variable delay between the external trigger pulse for a laser system and the light pulse such that the total delay is maintained at a substantially constant level and the overall delay between the external trigger pulse of the laser system and the light pulse is not effected by the HV, temperature change or other parameters such as material properties. The variable delay may be implemented with digital delay lines.

Abstract: An excimer or molecular fluorine laser system includes a discharge chamber containing a gas mixture, multiple electrodes connected to a power supply circuit for energizing the gas mixture, a resonator for generating a laser beam, a processor, and means for monitoring an amplified spontaneous emission (ASE) signal of the laser, such as preferably an ASE detector. The processor receives a signal from the preferred ASE detector indicative of the ASE signal of the laser. Based on the signal from the ASE detector, the processor determines whether to initiate a responsive action for adjusting a parameter of the laser system.

Abstract: An apparatus and method are provided for bandwidth narrowing of an excimer laser to &Dgr;&lgr;≈6 pm or less with high spectral purity and minimized output power loss. Output stability with respect to pulse energy, beam pointing, beam size and beam output location is also provided. The excimer laser includes an active laser medium for generating a spectral beam at an original wavelength, means for selecting and narrowing the broadband output spectrum of the excimer laser, a resonator having at least one highly reflecting surface, and an output coupler. Means for adapting a divergence of the resonating band within the resonator is further included in the apparatus of the invention. The divergence adapting causes the spectral purity to improve by between 20% and 50% and the output power to reduce by less than 10%. A method according to the invention includes selecting and aligning the divergence adapting means.

Abstract: An excimer or molecular fluorine laser system is provided which emits a laser beam during operation and has a gas mixture with a gas composition initially provided within a discharge chamber. The laser system includes a discharge chamber containing a laser gas mixture at least including a halogen-containing species and a buffer gas, multiple electrodes within the discharge chamber and connected to a discharge circuit for energizing the gas mixture, a resonator for generating a laser beam, an electrostatic precipitator for having a voltage applied thereto and for receiving and precipitating contaminant particulates from a flow of the gas mixture, and a processor for monitoring the corona discharge ignition voltage of the electrostatic precipitator and for determining a status of said gas mixture based on the monitored voltage.

Abstract: A molecular fluorine (F2) laser system includes a seed oscillator and power amplifier. The seed oscillator includes a laser tube including multiple electrodes therein which are connected to a discharge circuit. The laser tube is part of an optical resonator for generating a laser beam including a first line of multiple characteristic emission lines around 157 nm. The laser tube is filled with a gas mixture including molecular fluorine and a buffer gas. A low pressure seed radiation generating gas lamp is alternatively used. The gas mixture is at a pressure below that which results in the generation of a laser emission including the first line around 157 nm having a natural linewidth of less than 0.5 pm. The power amplifier amplifies the power of the beam emitted by the seed oscillator to a desired power for applications processing.

Abstract: A F2-laser includes a discharge chamber filled with a gas mixture including molecular fluorine for generating a spectral emission in a wavelength range between 157 nm and 158 nm including a primary line and a secondary line, multiple electrodes coupled with a power supply circuit for producing a pulsed discharge to energize the molecular fluorine, a resonator including the discharge chamber and an interferometric device for generating a laser beam having a bandwidth of less than 1 pm, and a wavelength monitor coupled in a feedback loop with a processor for monitoring a spectral distribution of the laser beam. The processor controls an interferometric spectrum of the interferometric device based on the monitored spectral distribution such that sidebands within the spectral distribution are substantially minimized.

Abstract: A molecular fluorine laser system emitting a narrow bandwidth laser beam and having efficient line-selection of a main line &lgr;1 of multiple closely-spaced lines around 157 nm includes a discharge chamber filled with a laser gas including molecular fluorine and a buffer gas, a gas handling module for periodically replenishing the molecular fluorine in the discharge chamber for maintaining said gas mixture at a selected composition, multiple electrodes within the discharge chamber and connected to a discharge circuit for energizing the molecular fluorine, and a resonator including the discharge chamber for generating a laser beam around 157 nm. The resonator further includes line-selection optics for selecting a main line &lgr;1 and suppressing a secondary line &lgr;2 of said plurality of closely-spaced lines.

Abstract: An F2-excimer laser has multiple closely-spaced spectral lines of interest around 157 nm, and one of the lines is selected by wavelength selection optics. The wavelength selection optics of a first preferred embodiment include a birefringent Brewster window enclosing the laser gas volume of the discharge chamber. The window preferably comprises MgF2 and is located at one end of the discharge chamber. One line is selected of the two when the optical thickness of the window is selected in coordination with rotatably adjustable, orthogonal refractive indices of the window. The transmissivity of the window is dependent on the orthogonal refractive indices and the optical thickness of the window. The wavelength selection optics of a second preferred embodiment include are at least partially within the laser active volume. In this way, line selection is performed in a manner which optimizes the combination of optical and discharge efficiency, resonator size and cost.

Abstract: Method and system for providing an excimer or molecular fluorine laser including a laser tube filled with a laser gas surrounded by an optical resonator, where the laser tube has multiple electrodes including a pair of main discharge electrodes connected to a discharge circuit for exciting the laser gas to produce a laser output beam. The discharge circuit has an all solid state switch and preferably does not include a transformer. The solid state switch includes multiple solid state devices that may be capable of switching voltages in excess of 12 kV, such as 14-32 kV or more, or the voltage needed to switch the laser. The series of switches has a rise time of approximately less than 300 ns, and preferably around 100 ns or less. The switch may be capable of switching voltages of slightly more than half, but less than the entire voltage needed to produce laser pulses of desired energies, and a voltage doubling circuit may be used to produce the voltage required to produce the desired output pulse energies.

Abstract: An F2-excimer laser has multiple closely-spaced spectral lines of interest around 157 nm, and one of the lines is selected by wavelength selection optics. The wavelength selection optics of a first preferred embodiment include a birefringent Brewster window enclosing the laser gas volume of the discharge chamber. The window preferably comprises MgF2 and is located at one end of the discharge chamber. One line is selected of the two when the optical thickness of the window is selected in coordination with rotatably adjustable, orthogonal refractive indices of the window. The transmissivity of the window is dependent on the orthogonal refractive indices and the optical thickness of the window. The wavelength selection optics of a second preferred embodiment include are at least partially within the laser active volume. In this way, line selection is performed in a manner which optimizes the combination of optical and discharge efficiency, resonator size and cost.

Abstract: An F2-excimer laser has multiple closely-spaced spectral lines of interest around 157 nm, and one of the lines is selected by wavelength selection optics. The wavelength selection optics of a first preferred embodiment include a birefringent Brewster window enclosing the laser gas volume of the discharge chamber. The window preferably comprises MgF2 and is located at one end of the discharge chamber. One line is selected of the two when the optical thickness of the window is selected in coordination with rotatably adjustable, orthogonal refractive indices of the window. The transmissivity of the window is dependent on the orthogonal refractive indices and the optical thickness of the window. The wavelength selection optics of a second preferred embodiment include are at least partially within the laser active volume. In this way, line selection is performed in a manner which optimizes the combination of optical and discharge efficiency, resonator size and cost.

Abstract: A wavelength calibration system determines an absolute wavelength of a narrowed spectral emission band of an excimer or molecular laser system. The system includes a module including an element which optically interacts with a component of an output beam of the laser within the tunable range of the laser system around the narrowed band. An inter-level resonance is detected by monitoring changes in voltage within the module, or photo-absorption is detected by photodetecting equipment. The absolute wavelength of the narrowed band is precisely determinable when the optical transitions occur and are detected. When the system specifically includes an ArF-excimer laser chamber, the module is preferably a galvatron containing an element that photo-absorbs around 193 nm and the element is preferably a gas or vapor selected from the group consisting of arsenic, carbon, oxygen, iron, gaseous hydrocarbons, halogenized hydrocarbons, carbon-contaminated inert gases, germanium and platinum vapor.

Abstract: A molecular fluorine laser system includes a discharge tube filled with a gas mixture including molecular fluorine and at least one buffer gas and having a total pressure of less than substantially 2500 mbar, multiple electrodes within the discharge tube, a pulsed discharge circuit connected to the electrodes for energizing the gas mixture, a line-selection optic for selecting one of multiple closely-spaced lines around 157 nm emitted from the discharge tube, and a laser resonator including the line-selection optic and the discharge tube for generating a beam of laser pulses having a wavelength around 157 nm at a bandwidth of less than 0.6 pm.

Abstract: A method is provided for determining the status of a gas mixture of a laser system including a gas discharge laser which generates an output beam and has a discharge chamber containing a gas mixture within which energy is supplied to the gas mixture by a power supply via application of a driving voltage to a discharge circuit. A master data set of an output parameter such as any of output beam energy, bandwidth, spectrum width, long axial beam profile, short axial beam profile, beam divergence, energy stability, energy efficiency, width of the discharge, temporal beam coherence, spatial beam coherence, spatial pulse width, amplified spontaneous emission and temporal pulse width versus an input parameter such as driving voltage is generated corresponding to an optimal gas mixture status, preferably after a new fill and typically at the factory, and alternatively following a new fill at the fab.

Abstract: An ultraviolet light detection system is provided wherein a dark current background growth rate with total accumulated exposure dose is avoided, and parameters of an ultraviolet radiation source such as an ArF-excimer laser may be monitored without rapid degradation of the signal by the superposition of the dark current background over a desired signal. The invention provides a detector including a light sensitive element having a frequency conversion coating on its surface. The coating is preferably directly on the light sensitive element, absorbing incident ultraviolet light and re-emitting visible light in a direction toward the light sensitive element. The coating minimizes a dark current background that would otherwise appear when incident ultraviolet light impinges directly upon the light sensitive element, and thereby extends a lifetime of the light sensitive element.

Abstract: A system is provided for delivering a laser beam of wavelength less than 200 nm from a laser, such as an F2 laser or ArF laser, through a sealed enclosure sealably connected to the laser, and preferably to another housing, leading ultimately to a workpiece. The enclosure is preferably evacuated and back-filled with an inert gas to adequately deplete any air, water, hydrocarbons or oxygen within the enclosure. Thereafter or alternatively, an inert gas flow is established and maintained within the enclosure during operation of the laser. The inert gas preferably has high purity, e.g., more than 99.5% and preferably more than 99.999%, wherein the inert is preferably nitrogen or a noble gas. The enclosure is preferably sealed by a window transparent to the sub-200 nm radiation for preventing contaminants generated in the enclosure from entering the housing and contaminating surfaces therein. The enclosure is preferably made of steel and/or copper, and the window is preferably made of CaF2.

Abstract: A diagnostic system is disclosed for monitoring the operation of an excimer laser. A typical excimer laser generates a light pulse in response to a trigger signal. The trigger signal propagates from an external source through a number of electrical modules to the gas discharge. In accordance with the subject invention, outputs from each of the various modules are supplied to digital counters. When the laser is operating properly, each counter will record a single count for each trigger signal. When a fault occurs, the number of counts counted by the counter connected to the faulty module will not match the number of trigger signals. The service engineer can use the information in the counters to help identify which module in the trigger chain is experiencing problems.

Abstract: An ultraviolet light detection system is provided wherein a dark current background growth rate with total accumulated exposure dose is avoided, and parameters of an ultraviolet radiation source such as an ArF-excimer laser may be monitored without rapid degradation of the signal by the superposition of the dark current background over a desired signal. The invention provides a detector including a light sensitive element having a frequency conversion coating on its surface. The coating is preferably directly on the light sensitive element, absorbing incident ultraviolet light and re-emitting visible light in a direction toward the light sensitive element. The coating minimizes a dark current background that would otherwise appear when incident ultraviolet light impinges directly upon the light sensitive element, and thereby extends a lifetime of the light sensitive element.

Abstract: A laser for an excimer or molecular fluorine laser includes an electrode chamber connected with a gas flow vessel and having a pair of main electrodes and a preionization unit each connected to a discharge circuit. A spoiler is provided within the electrode chamber and is shaped to provide a more uniform gas flow through the discharge area between the main electrodes, to shield one of the preionization units from one of the main electrodes, and to reflect acoustic waves generated in the discharge area into the gas flow vessel for absorption therein. A spoiler unit may include a pair of opposed spoiler elements on either side of the discharge area. One or both main electrodes includes a base portion and a center portion which may be a nipple protruding from the base portion. The center portion substantially carries the periodic discharge current such that the discharge width is and may be significantly less than the width of the base portion.