摘要:
A laser produced plasma (“LPP”) extreme ultraviolet (“EUV”) light source and method of operating same is disclosed which may comprise an EUV plasma production chamber having a chamber wall; a drive laser entrance window in the chamber wall; a drive laser entrance enclosure intermediate the entrance window and a plasma initiation site within the chamber and comprising an entrance enclosure distal end opening; at least one aperture plate intermediate the distal opening and the entrance window comprising at least one drive laser passage aperture. The at least one aperture plate may comprise at least two aperture plates comprising a first aperture plate and a second aperture plate defining an aperture plate interim space. The at least one drive laser aperture passage may comprise at least two drive laser aperture passages. The laser passage aperture may define an opening large enough to let the drive laser beam pass without attenuation and small enough to substantially reduce debris passing through the laser passage aperture in the direction of the entrance window.
摘要:
An DPP EUV source is disclosed which may comprise a debris mitigation apparatus employing a metal halogen gas producing a metal halide from debris exiting the plasma. The EUV source may have a debris shield that may comprise a plurality of curvilinear shield members having inner and outer surfaces connected by light passages aligned to a focal point, which shield members may be alternated with open spaces between them and may have surfaces that form a circle in one axis of rotation and an ellipse in another. The electrodes may be supplied with a discharge pulse shaped to produce a modest current during the axial run out phase of the discharge and a peak occurring during the radial compression phase of the discharge. The light source may comprise a turbomolecular pump having an inlet connected to the generation chamber and operable to preferentially pump more of the source gas than the buffer gas from the chamber. The source may comprise a tuned electrically conductive electrode comprising: a differentially doped ceramic material doped in a first region to at least select electrical conductivity and in a second region at least to select thermal conductivity. The first region may be at or near the outer surface of the electrode structure and the ceramic material may be SiC or alumina and the dopant is BN or a metal oxide, including SiO or TiO2. The source may comprise a moveable electrode assembly mount operative to move the electrode assembly mount from a replacement position to an operating position, with the moveable mount on a bellows. The source may have a temperature control mechanism operatively connected to the collector and operative to regulate the temperature of the respective shell members to maintain a temperature related geometry optimizing the glancing angle of incidence reflections from the respective shell members, or a mechanical positioner to position the shell members. The shells may be biased with a voltage. The debris shield may be fabricated using off focus laser radiation. The anode may be cooled with a hollow interior defining two coolant passages or porous metal defining the passages. The debris shield may be formed of pluralities of large, intermediate and small fins attached either to a mounting ring or hub or to each other with interlocking tabs that provide uniform separation and strengthening and do not block any significant amount of light.
摘要:
The present invention provides a modular high repetition rate ultraviolet gas discharge laser light source for a production line machine. The system includes an enclosed and purged beam path with beam pointing control for delivery the laser beam to a desired location such as the entrance port of the production line machine. In preferred embodiments, the production line machine is a lithography machine and 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. This MOPA system is capable of output pulse energies approximately double the comparable single chamber laser system with greatly improved beam quality. A pulse stretcher more than doubles the output pulse length resulting in a reduction in pulse power (mJ/ns) as compared to prior art laser systems. This preferred embodiment is capable of providing illumination at a lithography system wafer plane which is approximately constant throughout the operating life of the lithography system, despite substantial degradation of optical components.
摘要:
A trussed cross-flow blower comprising truss elements on the inside of a cylindrically-shaped cross-flow blower element form at least three trusses which provide rigidity to the blower element. Preferably three trusses are provided, and they are located at radial 120.degree. spacings.
摘要:
A beam delivery unit and method of delivering a laser beam from a laser light source for excimer or molecular fluorine gas discharge laser systems in the DUV and smaller wavelengths is disclosed, which may comprise: a beam delivery enclosure defining an output laser light pulse beam delivery pat from an output of a gas discharge laser to an input of a working apparatus employing the light contained in the output laser light pulse beam; a purge mechanism operatively connected to the beam delivery enclosure; an in-situ beam parameter monitor and adjustment mechanism within the enclosure, comprising a retractable bean redirecting optic; a beam analysis mechanism external to the enclosure; and, a retraction mechanism within the enclosure and operable from outside the enclosure and operative to move the retractable beam redirecting optic from a retracted position out of the beam path to an operative position in the beam path. The BDU may also include a beam attenuator unit contained within the enclosure adjustably mounted within the enclosure for positioning within the beam delivery pat. The BDU may have at least two enclosure isolation mechanisms comprising a first enclosure isolation mechanism on a first side of the enclosure from the at least one optic module and a second enclosure isolation mechanism on a second side of the enclosure from the at least one optic module, each respective enclosure isolation mechanism comprising a flapper valve having a metal to metal seating mechanism and a locking pin assembly. A precision offset ratchet driver operative to manipulate actuator mechanisms in difficult to reach locations may be provided. An external kinematic alignment tool may be provided. A method of contamination control for a BDU is disclosed comprising selection of allowable materials and fabrication processes.
摘要:
The present invention provides an electric discharge gas laser having a laser cavity in which is contained a laser gas and a fan for circulating the laser gas. The fan is supported by an active radial magnetic bearing system and driven by a brushless DC motor in which the rotor of the motor and the rotors of at least two radial bearings are sealed within the gas environment of the laser cavity and the motor stator and the coils of the bearing magnets are located outside the gas environment. No thrust bearing is provided. Axial positioning of the shaft is provided by reluctance centering produced by the at least two radial magnetic bearings and the brushless DC motor. In a preferred embodiment the motor stator is larger in the axial direction than the rotor to increase the magnetic centering effect.
摘要:
The present invention provides a modular high repetition rate ultraviolet gas discharge laser light source with a beam delivery to a production line machine. The system includes an enclosed and purged beam path with beam pointing control for delivery the laser beam to a desired location such as the entrance port of the production line machine. Preferred embodiments include equipment for beam attenuation, equipment for automatic feedback beam alignment and equipment for accurate optics module positioning at installation and during maintenance. In preferred embodiments, the production line machine is a lithography machine and 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. This MOPA system is capable of output pulse energies approximately double the comparable single chamber laser system with greatly improved beam quality. A pulse stretcher more than doubles the output pulse length resulting in a reduction in pulse power (mJ/ns) as compared to prior art laser systems. This preferred embodiment is capable of providing illumination at a lithography system wafer plane which is approximately constant throughout the operating life of the lithography system, despite substantial degradation of optical components.
摘要:
An improved applanation lens and method for use in an interface between a patient's eye and a surgical laser system does not discolor or lose light transmittance when subjected to gamma radiation. The improved applanation lens has an applanation surface configured to contact the eye upon application of a pressure. The lens is formed of high purity silicon dioxide (SiO2) with purity great enough to resist discoloration upon prolonged irradiation by high-energy radiation such as UV, x-rays, gamma rays or neutrons, and is preferably a fused silica.
摘要:
A support bar member for supporting an electrode member of a pulsed laser system is described. The support bar member includes an aerodynamic nose configured to reduce an aerodynamic load applied against a blower assembly of the laser system by the support bar member. The nose provides an aerodynamic cut-off region on the support bar member such that, when the blower assembly is operating, the blower assembly does not vibrate significantly.
摘要:
A tangential fan and cutoff assembly for recirculating a lasing gas mixture has blade members, which vary in circumferential position stepwise from end to end, and/or a tapered anode assembly. The number of blade members can be constant or variable between ends. The circumferential position of blade members can shift monotonically or reversibly between ends. Blade members are stiffened by optimally selecting the number and placement of hub members to control the natural vibration frequency of the fan. Methods of forming tangential fans include casting, and machining from a solid block. Monolithic structures can be joined, typically by electron-beam welding. Casting, welding, and machining processes introduce no additional contaminants. Tangential fans produced have mechanical rigidity, accurate tolerances, and low contaminant concentrations. Blade members can be formed into air foil shapes.