摘要:
A line narrowed gas discharge laser system and method of operation are disclosed which may comprise: an oscillator cavity; a laser chamber comprising a chamber housing containing a lasing medium gas; at least one peaking capacitor electrically connected to the chamber housing and to a first one of a pair of electrodes; a second one of the pair of electrodes connected to an opposite terminal of the at least one peaking capacitor; a current return path connected to the chamber housing; the one terminal, the first one of the electrodes, the lasing medium gas, the second one of the electrodes, the current return path and the second terminal forming a head current inductive loop having an inductance unique to the particular head current inductive loo; a spectral quality tuning mechanism comprising a mechanism for changing the particular head current inductive loop inductance value for the particular head current inductance loop.
摘要:
An oscillator-amplifier gas discharge laser system and method is disclosed which may comprise a first laser unit which may comprise a first discharge region which may contain an excimer or molecular fluorine lasing gas medium; a first pair of electrodes defining the first discharge region containing the lasing gas medium, a line narrowing unit for narrowing a spectral bandwidth of output laser light pulse beam pulses produced in said first discharge region; a second laser unit which may comprise a second discharge chamber which may contain an excimer or molecular fluorine lasing gas medium; a second pair of electrodes defining the second discharge region containing the lasing gas medium; a pulse power system providing electrical pulses to the first pair of electrodes and to the second pair of electrodes producing gas discharges in the lasing gas medium between the respective first and second pair of electrodes, and laser parameter control mechanism modifying a selected parameter of a selected laser output light pulse beam pulse produced by said gas discharge laser system by controlling the timing of the occurrence of the gas discharge between the first pair of electrodes and the occurrence of the gas discharge between the second pair of electrodes.
摘要:
An oscillator-amplifier gas discharge laser system and method is disclosed which may comprise a first laser unit which may comprise a first discharge region which may contain an excimer or molecular fluorine lasing gas medium; a first pair of electrodes defining the first discharge region containing the lasing gas medium, a line narrowing unit for narrowing a spectral bandwidth of output laser light pulse beam pulses produced in said first discharge region; a second laser unit which may comprise a second discharge chamber which may contain an excimer or molecular fluorine lasing gas medium; a second pair of electrodes defining the second discharge region containing the lasing gas medium; a pulse power system providing electrical pulses to the first pair of electrodes and to the second pair of electrodes producing gas discharges in the lasing gas medium between the respective first and second pair of electrodes, and laser parameter control mechanism modifying a selected parameter of a selected laser output light pulse beam pulse produced by said gas discharge laser system by controlling the timing of the occurrence of the gas discharge between the first pair of electrodes and the occurrence of the gas discharge between the second pair of electrodes.
摘要:
A method and apparatus for debris removal from a reflecting surface of an EUV collector in an EUV light source is disclosed which may comprise the reflecting surface comprises a first material and the debris comprises a second material and/or compounds of the second material, the system and method may comprise a controlled sputtering ion source which may comprise a gas comprising the atoms of the sputtering ion material; and a stimulating mechanism exciting the atoms of the sputtering ion material into an ionized state, the ionized state being selected to have a distribution around a selected energy peak that has a high probability of sputtering the second material and a very low probability of sputtering the first material. The stimulating mechanism may comprise an RF or microwave induction mechanism.
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:
An EUV light source collector erosion mitigation system and method is disclosed which may comprise a collector comprising a multilayered mirror collector comprising a collector outer surface composed of a capping material subject to removal due to a removing interaction with materials created in an EUV light-creating plasma; a replacement material generator positioned to deliver replacement material comprising the capping material to the collector outer surface at a rate sufficient to replace the capping material removed due to the removing interaction. The replacement material generator may comprise a plurality of replacement material generators positioned to respectively deliver replacement material to a selected portion of the collector outer surface, which may comprise a sputtering mechanism sputtering replacement capping material onto the collector outer surface.
摘要:
An apparatus and method for providing bandwidth control in a narrow band short pulse duration gas discharge laser output light pulse beam producing system, producing a beam comprising laser output light pulses at a selected pulse repetition rate, is disclosed which may comprise 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 laser light pulse beam containing the respective pulse on the dispersive wavelength selection optic; a tuning mechanism operative to select at least one angle of incidence of the a laser light pulse beam containing the respective pulse upon the dispersive center wavelength selection 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 laser light pulse to return from the dispersive center wavelength selection optic a laser light pulse comprising a plurality of spatially separated but not temporally separated portions, each portion having one of at least two different selected center wavelengths. The tuning mechanism may comprise a temporal angle of incidence selection element defining an angle of incidence for different temporally separated portions of the pulse to return from the dispersive bandwidth selection optic a laser beam comprising a plurality of temporally separated portions of each pulse, each temporally separated portion of each pulse having one of at least two different selected center wavelengths. The tuning mechanism may comprise a plurality of spatial incidence angle selection elements each defining an angle of incidence for a spatially separated but not temporally separated portion of the laser light pulse, and a plurality of temporal angle of incidence selection elements each defining at least a first angle of incidence for at least a first temporally separated portion of each spatially separated but not temporally separated portion of the pulse and a second angle of incidence for a second temporally separated but not spatially separated portion of each spatially separated portion of the pulse.
摘要:
Systems and methods are disclosed for reducing the influence of plasma generated debris on internal components of an EUV light source. In one aspect, an EUV metrology monitor is provided which may have a heater to heat an internal multi-layer filtering mirror to a temperature sufficient to remove deposited debris from the mirror. In another aspect, a device is disclosed for removing plasma generated debris from an EUV light source collector mirror having a different debris deposition rate at different zones on the collector mirror. In a particular aspect, an EUV collector mirror system may comprise a source of hydrogen to combine with Li debris to create LiH on a collector surface; and a sputtering system to sputter LiH from the collector surface. In another aspect, an apparatus for etching debris from a surface of a EUV light source collector mirror with a controlled plasma etch rate is disclosed.
摘要:
The present invention provides a reliable, high-repetition rate, production line compatible high energy photon source. A very hot plasma containing an active material is produced in vacuum chamber. The active material is an atomic element having an emission line within a desired extreme ultraviolet (EUV) range. A pulse power source comprising a charging capacitor and a magnetic compression circuit comprising a pulse transformer, provides electrical pulses having sufficient energy and electrical potential sufficient to produce the EUV light at an intermediate focus at rates in excess of 5 Watts. In preferred embodiments designed by Applicants in-band, EUV light energy at the intermediate focus is 45 Watts extendable to 105.8 Watts.
摘要:
An apparatus and method is described for effectively and efficiently providing plasma irradiation laser light pulses in an LPP EUV light source which may comprise a laser initial target irradiation pulse generating mechanism irradiating a plasma initiation target with an initial target irradiation pulse to form an EUV generating plasma having an emission region emitting in-band EUV light; a laser plasma irradiation pulse generating mechanism irradiating the plasma with a plasma irradiation pulse after the initial target irradiation pulse so as to compress emission material in the plasma toward the emission region of the plasma. The plasma irradiation pulse may comprise a laser pulse having a wavelength that is sufficiently longer than a wavelength of the initial target irradiation pulse to have an associated lower critical density resulting in absorption occurring within the plasma in a region of the plasma defined by the wavelength of the plasma irradiation pulse sufficiently separated from an initial target irradiation site to achieve compression of the emission material, and the may compress the emission region. The laser plasma irradiation pulse may produce an aerial mass density in the ablating cloud of the plasma sufficient to confine the favorably emitting plasma for increased conversion efficiency. The deposition region for the plasma irradiation pulse may be is removed enough from the initial target surface so as to insure compression of the favorably emitting plasma. A high conversion efficiency laser produced plasma extreme ultraviolet (“EUV”) light source may comprise a laser initial target irradiation pulse generating mechanism irradiating a plasma initiation target with a target irradiation pulse to form an EUV generating plasma emitting in-band EUV light; a plasma tamper substantially surrounding the plasma to constrain the expansion of the plasma.