Abstract: A thermally regulated component is an optical element or chuck for holding an optical element, or a stage for same, or combination thereof. The component has first and second heat-transfer zones. The first has a first component surface that receives a heating influence such as incident electromagnetic radiation. The second has a second component surface. A conduit circuit extends in the component serially through the first and second heat-transfer zones, back to the first heat-transfer zone, and contains an electrically conductive liquid (e.g., liquid metal). A vibration-free pump (e.g., MFD pump) coupled to the conduit circuit induces flow of the liquid through the circuit. A heat-exchanger is in thermal contact, but not actual contact, with the second component surface. Thus, heat delivered to the second heat-transfer zone by the liquid flowing in the conduit circuit flows from the second component surface to the heat-exchanger.

Abstract: An exemplary thermally regulated component is an optical element or chuck for holding an optical element, or a stage for same, or combination thereof. The component has first and second heat-transfer zones. The first has a first component surface that receives a heating influence such as incident electromagnetic radiation. The second has a second component surface. A conduit circuit extends in the component serially through the first and second heat-transfer zones, back to the first heat-transfer zone, and contains an electrically conductive liquid (e.g., liquid metal). A vibration-free pump (e.g., MFD pump) coupled to the conduit circuit induces flow of the liquid through the circuit. A heat-exchanger is in thermal contact, but not actual contact, with the second component surface. Thus, heat delivered to the second heat-transfer zone by the liquid flowing in the conduit circuit flows from the second component surface to the heat-exchanger.

Abstract: Apparatus are disclosed for measuring the position of an object surface along an axis. An exemplary apparatus has at least one actuator coupled to a fixed member such as a metrology frame. At least one analog proximity sensor is coupled to the at least one actuator. The at least one actuator is controllably operated to position the at least one proximity sensor at a fixed distance along the axis from a surface that is fixed relative to the fixed me+mber. A controller, coupled to the actuator and to the proximity sensor, is configured to compute a position of the object surface along the axis based on a known location of the fixed surface along the axis, the fixed distance from the fixed surface, and position signals from the at least one proximity sensor.

Abstract: Apparatus are disclosed for measuring the position of an object surface along an axis. An exemplary apparatus has at least one actuator coupled to a fixed member such as a metrology frame. At least one analog proximity sensor is coupled to the at least one actuator. The at least one actuator is controllably operated to position the at least one proximity sensor at a fixed distance along the axis from a surface that is fixed relative to the fixed me+mber. A controller, coupled to the actuator and to the proximity sensor, is configured to compute a position of the object surface along the axis based on a known location of the fixed surface along the axis, the fixed distance from the fixed surface, and position signals from the at least one proximity sensor.

Abstract: An exemplary apparatus includes a controllably movable body, a holding device, and a coolant circulation device. The body comprises a wall including a planar contact surface that receives the reverse surface of the article. The wall co-extends with at least a heat-receiving area of the utility surface whenever the article is being held by the body. The wall also includes a second surface separated from but proximal to the contact surface, and is thermally conductive from the contact surface to the second surface. The holding device holds the article to the contact surface with the reverse surface contacting the contact surface. The coolant circulation device delivers flow of a coolant fluid to the second surface to urge conduction of heat from the contact surface to the second surface. The holding device and coolant-circulation device operate in concert to actively control shape of the article being held by the apparatus.

Abstract: A fluid gauge (222) for measuring the position of a work piece (200) includes a gauge body (236), a fluid source assembly (238), and a gauge control system (240). The gauge body (236) includes a measurement conduit (246), a first reference conduit (248A), a second reference conduit (248B), a first reference surface (250A) that is spaced apart a first reference gap (242A) from an outlet (254) of the first reference conduit (248A), and a second reference surface (250B) that is spaced apart a second reference gap (242B) from an outlet (254) of the second reference conduit (248B). The gauge body (236) is positioned so that an outlet (254) of the measurement conduit (246) is spaced apart a measurement gap (244) from the work piece (200). Further, the fluid source assembly (238) directs a fluid (260) into the conduits (246), (248A), (248B).

Abstract: An electrostatic chuck (230) for holding a device (200) includes a chuck body (244), a Coulomb electrode assembly (246), a Johnsen-Rahbek (J-R) electrode assembly (248), and a control system (224). The chuck body (244) includes a chucking surface (250) that engages the device (200), and the chuck body (244) is made of a dielectric having a relatively high resistance. The J-R electrode assembly (248) is positioned spaced apart from the chucking surface (250). The Coulomb electrode assembly (246) is also positioned spaced apart from the chucking surface (250). The control system (224) selectively directs a first voltage to the J-R electrode assembly (248) to generate a J-R type force that attracts the device (200) towards the chucking surface (250), and selectively directs a second voltage to the Coulomb electrode assembly (246) to generate a Coulomb type force that also attracts the device (200) towards the chucking surface (250).

Abstract: An exemplary apparatus includes a controllably movable body, a holding device, and a coolant circulation device. The body comprises a wall including a planar contact surface that receives the reverse surface of the article. The wall co-extends with at least a heat-receiving area of the utility surface whenever the article is being held by the body. The wall also includes a second surface separated from but proximal to the contact surface, and is thermally conductive from the contact surface to the second surface. The holding device holds the article to the contact surface with the reverse surface contacting the contact surface. The coolant circulation device delivers flow of a coolant fluid to the second surface to urge conduction of heat from the contact surface to the second surface. The holding device and coolant-circulation device operate in concert to actively control shape of the article being held by the apparatus.

Abstract: A fluid gauge (222) for measuring the position of a work piece (200) includes a gauge body (236), a fluid source assembly (238), and a gauge control system (240). The gauge body (236) includes a measurement conduit (246), a first reference conduit (248A), a second reference conduit (248B), a first reference surface (250A) that is spaced apart a first reference gap (242A) from an outlet (254) of the first reference conduit (248A), and a second reference surface (250B) that is spaced apart a second reference gap (242B) from an outlet (254) of the second reference conduit (248B). The gauge body (236) is positioned so that an outlet (254) of the measurement conduit (246) is spaced apart a measurement gap (244) from the work piece (200). Further, the fluid source assembly (238) directs a fluid (260) into the conduits (246), (248A), (248B).

Abstract: Methods and apparatus for compensating for forces applied by a system which measures a height of a photoresist-coated surface of a wafer are disclosed. According to one aspect, a method for measuring a height associated with a wafer includes utilizing a measurement of an air flow through an air gauge or air bearing to estimate the height, determining a first magnitude of a bearing load exerted on the wafer from the air flow measurement, and compensating for the bearing load. The bearing load is exerted by an arrangement configured to determine the height associated with the wafer a first direction. Compensating for the bearing load includes applying an opposing force to the wafer that includes at least a vacuum preload force. The vacuum preload force is applied in a second direction that is opposite from the first direction. The opposing force is calculated to have a second magnitude that is approximately equal to the first magnitude.

Abstract: Apparatus and methods are disclosed for reducing particle contamination of a surface of an object such as a reticle used in an EUV lithography system. An exemplary apparatus includes a thermophoresis device and an electrophoresis device. The thermophoresis device is situated relative to and spaced from the surface, and is configured to produce a thermophoretic force, in a gas flowing past and contacting the surface, sufficient to inhibit particles in the gas from contacting the surface. The electrophoresis device is situated relative to a region of the surface contacted by the gas and is configured to deflect particles, having an electrostatic charge, in the gas away from the region as the gas flows past the region.

Abstract: Process tools and methods are disclosed that involve interferometric and other measurements of movements and positions relative to a process position, such as movements and positions of a stage relative to a lithographic optical system. An exemplary apparatus includes a stage that places a workpiece relative to the tool, and that is movable in at least one direction relative to the tool. At least one first interferometer system is situated relative to the stage to determine stage position in a movement direction relative to the process position. A movement-measuring device determines displacement of the tool from the process position. Using data from the interferometer system and movement-measuring device a processor determines a position of the stage relative to the tool. The processor also corrects the determined position for displacement of the tool.

Abstract: An enclosure for protecting at least a pattern side and an opposing side of a reticle is disclosed. The enclosure includes a first and second part that form an enclosure around a reticle to be protected during handling, inspection, storage, and transport. A method for transporting the reticle to an exposure position from a position outside an exposure chamber is disclosed, including a method for use of a load-lock chamber.

Abstract: An exemplary thermally regulated component is an optical element or chuck for holding an optical element, or a stage for same, or combination thereof. The component has first and second heat-transfer zones. The first has a first component surface that receives a heating influence such as incident electromagnetic radiation. The second has a second component surface. A conduit circuit extends in the component serially through the first and second heat-transfer zones, back to the first heat-transfer zone, and contains an electrically conductive liquid (e.g., liquid metal). A vibration-free pump (e.g., MFD pump) coupled to the conduit circuit induces flow of the liquid through the circuit. A heat-exchanger is in thermal contact, but not actual contact, with the second component surface. Thus, heat delivered to the second heat-transfer zone by the liquid flowing in the conduit circuit flows from the second component surface to the heat-exchanger.

Abstract: Optical windows are provided that transmit light such as deep-UV (DUV) light. An exemplary window includes a window substrate that is transmissive to at least one wavelength of the light. The window substrate has an incidence surface decorated with sub-wavelength asperities arranged so as to render the incidence surface solvophobic to the light-transmissive liquid. The arrangement of sub-wavelength asperities can be configured to render the incidence surface super-solvophobic to the liquid. The sub-wavelength asperities can have any of various shapes and combinations thereof, and can be regularly or irregularly arranged.

Abstract: Optical windows are provided that transmit light such as deep-UV (DUV) light. An exemplary window includes a window substrate that is transmissive to at least one wavelength of the light. The window substrate has an incidence surface decorated with sub-wavelength asperities arranged so as to render the incidence surface solvophobic to the light-transmissive liquid. The arrangement of sub-wavelength asperities can be configured to render the incidence surface super-solvophobic to the liquid. The sub-wavelength asperities can have any of various shapes and combinations thereof, and can be regularly or irregularly arranged.

Abstract: An exemplary interferometer system includes an interferometer producing data from at least one interferometer beam. A source of gently flowing gas or gas mixture (atmosphere) produces a gas flow substantially normal to the beam pathway. A perturbation source (e.g., resistance heater) upstream of the beam pathway produces, in a repetitively pulsed manner, perturbed loci in the flowing atmosphere in selected locations upstream of the beam pathway. The perturbed loci flow to the interferometer beam(s). Data from the interferometer are received by a processor programmed with an algorithm that calculates, based on the data obtained during a perturbation pulse, the effect of the perturbed loci on the at least one interferometer beam as the loci pass through the interferometer beam. The processor also updates the algorithm based on data obtained from the interferometer during a subsequent perturbation pulse, compared to a previous perturbation pulse.

Abstract: Spectral-purity filters (SPFS) are disclosed that produce a stream of “SPF gas” through which a beam of light, particularly a beam including extreme ultraviolet (EUV) light, is allowed to pass. The SPF can be located in a system that receives a beam of EUV-containing light from a source and delivers the beam to a downstream EUV-optical system, wherein the beam from the source passes through the SPF to the optical system. The gaseous SPF is formulated and configured to enrich the beam in at least one EUV wavelength as the beam passes through the gaseous SPF. For enrichment of EUV wavelengths, an exemplary SPF gas is ZrCl4. The stream of SPF gas can be sheathed in an inert “sheath gas.” The gaseous SPF is usable in a vacuum environment, in which used SPF gas, and sheath gas if used, is collected.

Abstract: Gaseous neutral density (ND) filters are disclosed that produce a stream of gas to interact with and thereby attenuate a beam of extreme ultraviolet (EUV) radiation. The gaseous ND filter can be located in a system that receives the beam of EUV radiation from an EUV source and delivers the beam to a downstream EUV optical system, wherein the beam passes through the gaseous ND filter between the source and the optical system. The stream of gas used in the gaseous ND filter can be discharged at a supersonic velocity and the gas can be a single gas or a mixture of gases. An exemplary mixture of gases includes xenon and argon gases.

Abstract: Devices and methods are disclosed for reducing coherence, and thus speckle, of a coherent beam of light. An exemplary illumination device includes a source emitting a pulsed coherent light beam having a transverse spatial coherence length. A deflector positioned in the path spatially displaces a first portion of a beam pulse from a second portion of the beam pulse, where the second portion is later in time than the first portion. A diffuser situated in the path receives the first portion of the beam pulse on a first region of the diffuser and the second portion of the beam pulse on a second region of the diffuser, such that the first and second regions are separated by a distance at least equal to the transverse spatial coherence length.