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 beam parameter monitoring unit for coupling with a molecular fluorine (F2) or ArF laser resonator that produces an output beam having a wavelength below 200 nm includes a detector and a beam path enclosure. The unit may also include a beam splitter within the enclosure for separating the output beam into first and second components, or first and second beam are attained by other means. The detector measures at least one optical parameter of the second component of the output beam. The beam path enclosure includes one or more ports for purging the beam path enclosure with an inert gas to maintain the enclosure substantially free of sub-200 nm photoabsorbing species.

Abstract: A technique of stabalizing during operation a gas mixture with a gas composition initially provided within a discharge chamber of an excimer or molecular fluorine gas discharge laser includes monitoring a temporal pulse shape of the laser beam and adjusting and/or determining the status of the gas mixture based on the monitored temporal pulse shape. The monitored temporal pulse shape is preferably compared with a reference temporal pulse shape. The difference or deviation between the monitored temporal pulse shape and a reference temporal pulse shape is calculated. The amount of and intervals between gas replenishment actions are determined based on the calculated deviation. The energy of the beam is also monitored and the driving voltage and gas actions are adjusted to stabilize the energy, energy stability and/or energy dose.

Abstract: The invention relates to a device for monitoring the transport process of flat despatches with a sensor, a store and an evaluation device, in which the device, takes the form of a flat despatch having a number of different regions, especially rigid and flexible regions. According to the invention, the regions are formed in such a way that the device has comparable machine compatibility and solidity to ordinary despatches. The regions consist of component, stamping and franking (1), belt-running (2, 3), buffer and intake (4) and bend and fold regions (6).

Abstract: An F.sub.2 -laser has a discharge chamber containing a laser gas mixture including fluorine as a laser active component and neon as a buffer gas. The gas mixture is surrounded by a resonator and supplied with a pulsed discharge by a pair of electrodes connected to a power supply circuit. The concentration of neon within the gas mixture is preferably higher than any other constituent gas, and is more preferably the only gas accompanying the laser active molecular fluorine. In addition, the gas mixture is preferably maintained at an elevated temperature such as near, yet below, a temperature at which outgassing occurs within the discharge chamber.

Abstract: An electrode for a gas discharge laser. Electrodes which consist, at least in part, of zirconium are suggested for use in gas discharge lasers containing fluorine.

Abstract: An apparatus for purifying laser gas, in particular for excimer and F.sub.2 lasers, employs liquid nitrogen (12) for freezing impurities out of the laser gas, the freeze-out temperature being set by means of the pressure above the surface (14) of the liqid nitrogen (12).

Abstract: An excimer laser including a gas reservoir in which gas discharge is effected with the participation of halogen gas, comprises a collecting receptacle which communicates both with the gas reservoir and a halogen gas supply through conduits provided with shutoff valves. This apparatus is suitable for carrying out a method of refilling the gas reservoir of the excimer laser with halogen gas even if the pressure of the halogen gas supply is low and its volume restricted.

Abstract: Laser comprising at least one anode (1) and one cathode (2) for preionization and main discharge, the anode (1) and the cathode (2) having different standard potentials. The laser is distinguished by high reliability and long life. After several hours of operation, practically no material erosion at all is found at the electrodes.

Abstract: An excimer laser having a chamber (10) in which a gas-discharge is performed with participation of hydrogen-chloride comprises means with which the hydrogen chloride is formed by hydrolysis.

Abstract: An apparatus for purifying laser gas, in particular for excimer and F.sub.2 lasers, employs liquid nitrogen (12) for freezing impurities out of the laser gas, the freeze-out temperature being set by means of the pressure above the surface (14) of the liquid nitrogen (12).

Abstract: In an apparatus for purifying laser gas, comprising a cooling circuit for cleaning of the laser gas, the cooling circuit is separable from the laser and operable by way of a shunt line, independently of the laser.

Abstract: An apparatus for purifying laser gas comprises first and second tubes 20, 22 in good thermal contact, liquid nitrogen flowing through the first tube 20 and laser gas flowing through the second tube 22. The laser gas is precooled in an arrangement of third and fourth tubes 24, 26, the laser gas to be cleaned entering the third tube 24 which opens into the second tube 22 so that precooled laser gas enters the second tube which opens into the fourth tube to effect the precooling.