Classifications

• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
  • G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
  • G02B26/0875—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more refracting elements
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
  • G02B26/06—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the phase of light
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
  • G02B27/0025—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for optical correction, e.g. distorsion, aberration
  • G02B27/0068—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for optical correction, e.g. distorsion, aberration having means for controlling the degree of correction, e.g. using phase modulators, movable elements
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B3/00—Simple or compound lenses
  • G02B3/02—Simple or compound lenses with non-spherical faces
  • G02B3/04—Simple or compound lenses with non-spherical faces with continuous faces that are rotationally symmetrical but deviate from a true sphere, e.g. so called "aspheric" lenses
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70058—Mask illumination systems
  • G03F7/7015—Details of optical elements
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70058—Mask illumination systems
  • G03F7/70191—Optical correction elements, filters or phase plates for controlling intensity, wavelength, polarisation, phase or the like
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70216—Mask projection systems
  • G03F7/70308—Optical correction elements, filters or phase plates for manipulating imaging light, e.g. intensity, wavelength, polarisation, phase or image shift
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B3/00—Simple or compound lenses
  • G02B3/0081—Simple or compound lenses having one or more elements with analytic function to create variable power

Definitions

• Optical correction arrangement projection objective with such an optical correction arrangement as well as a microlithographic apparatus with such a projection objective
• the invention relates to an optical correction arrangement with a first and a second correction component, which are arranged along an optical axis one behind the other, wherein the first and the second correction component are provided with aspheric surface contours, which in a zero position of the optical correction arrangement at least approximately total to zero, a manipulator for moving the first correction component in a first direction at a first speed and for moving the second correction component in a second direction at a second speed.
• the invention further relates to a projection objective having such an optical correction arrangement and to a microlithographic apparatus for microlithography, in particular a projection exposure apparatus, having such a projection objective.
• An optical correction arrangement of the type mentioned is known from DE 10 2007 046 419 A1.
• Such an optical correction arrangement is used in microlithography in order to change optical wavefronts of a projection objective, in particular in order to correct them.
• Microlithography also known as photolithography or lithography, is one of the central technologies of semiconductor and microsystem technology for the manufacture of integrated circuits, semiconductor devices, and other electronic products.
• the basic idea of microlithography is to transfer predefined structures to a substrate by means of exposure processes.
• the predefined structures are mounted on a reticle (also known as a "photomask") and typically include micro and / or nanostructures.
• the substrate for example a silicon wafer, is coated with a photosensitive material.
• the exposure light acts on the photosensitive material after passing through the projection lens, so that the areas of the photosensitive coating exposed to the exposure light change with regard to their chemical properties.
• the photosensitive material is subsequently removed with a solvent.
• the substrate material in the now exposed areas of the substrate surface is removed by means of an etchant in order to transfer the predefined structures of the reticle to the substrate surface.
• the imaging properties of the projection lens are subject to ever increasing demands.
• aberrations may be both production-related aberrations that are inherent even after production of the projection lens, as well as occurring only during operation of the projection lens aberrations.
• optical elements of the projection lens may be compromised due to exposure to high energy short wavelength exposure light, particularly ultraviolet (UV), vacuum ultraviolet (VUV), and extreme ultraviolet (EUV) light, and the concomitant overheating.
• correction arrangements are known from the prior art.
• the cited prior art discloses a projection lens having an optical correction arrangement of a plurality of optical correction elements.
• the correction elements are provided with aspheric surface contours, which add up to a total of at least approximately zero in a zero position.
• at least one of the correction elements is movable relative to at least one of the other correction elements in the direction of the optical axis in order to set a desired correction effect.
• EP 0 851 304 A2 discloses a further correction arrangement with a plurality of movable plates, wherein the different plates are movable in two opposite horizontal directions perpendicular to the optical axis.
• the above-mentioned known correction devices have a significant drawback that they are unable to satisfactorily correct aberrations that occur during the scanning process.
• the on the reticle entering light beam along a horizontal direction perpendicular to the optical axis of the projection lens moves the reticle.
• so-called "overlay" errors occur, which come about as a consequence, for example, of telecentric errors in connection with the change of the focal position during the scanning.
• Such aberrations can take on complicated field curves which can be mathematically described only with Zernike coefficients of higher orders. Such aberrations can not be corrected or are only partially corrected by the correction arrangements known from the prior art.
• this object is achieved in terms of the above-mentioned optical correction arrangement in that the first speed is higher than the second speed.
• the first and second correction components are provided with aspherical surface contours.
• the respective aspherization can be provided on the inside of the first or second correction component, which faces the intermediate space between the two correction components.
• an outer side of the first and / or the second correction component facing away from the intermediate space can be provided with an aspherical surface contour.
• the aspherical surface contours add up to at least approximately zero in the zero position of the optical correction arrangement.
• the optical effects of the aspheric surface contours compensate each other in the zero position of the correction arrangement, so that in the zero position the exposure light is transmitted at least approximately unchanged by the optical correction arrangement.
• the first and second correction components are movable by means of the manipulator, so that they are displaced relative to one another can.
• the manipulator is configured to move the first correction component at a first speed and to move the second correction component at a second speed, wherein the first speed is higher than the second speed.
• a desired correction effect can be achieved in order to correct optical aberrations, in particular field-dependent aberrations.
• aberrations such as overlay errors associated with defective surfaces or surface roughnesses of the reticle surface in the object plane and / or the substrate surface in the image plane can be corrected with increased accuracy and reliability.
• a shift of the object plane or the image plane and thus also the focus position of the projection lens is accompanied.
• the surfaces of the reticle and / or the substrate can be measured before the scanning process.
• the measured data can be supplied to the manipulator for controlling the correction components.
• the manipulator moves the first and / or the second correction component to effect a relative movement between the two correction components. Because the travel speeds of the first and second correction components can be selected differently from one another, the relative movement generated can be advantageously adapted to the measured surface course of the reticle surface or the substrate surface.
• the first speed is at least an order of magnitude higher than the second speed.
• the first and the second correction component can be moved at significantly different speeds from each other.
• the first correction component can be moved much faster than the second correction component, for example, it can be moved faster by at least a factor of 10.
• a fast relative movement between the correction components which is adapted to the temporally rapidly changing focus shift of the projection lens, is thereby achieved.
• dynamic correction of aberrations such as overlay errors during the scan, for example during exposure of a wafer or semiconductor die, is advantageously accomplished.
• aberrations which change comparatively slowly over time can be effectively corrected by the method of the second correction component.
• the manipulator is adapted to move the first correction component in accordance with a vibrational movement along the first direction.
• the oscillation movement is a periodic oscillation movement whose period is adapted to an exposure time for a semiconductor chip.
• the exposure of a single die typically occurs in two steps: a first step of preparation to adjust the projection lens and a second scan to scan through the die.
• the exposure time for a die is therefore calculated by adding the duration of both steps ("step and scan").
• step and scan the movement of the first correction component along the first direction produces a periodic compensation of the focus shift of the projection lens. Consequently, temporally recurring overlay errors can be corrected with particularly high accuracy.
• the period of the oscillatory movement is below 100 ms, preferably below 80 ms, more preferably below 40 ms.
• a frequency of the oscillatory motion which is at least 10 Hz, preferably at least 12.5 Hz, more preferably at least 25 Hz.
• the oscillation movement of the first correction component can thus be adapted particularly effectively to a scan rhythm of the projection objective which is typical in microlithography.
• the first speed of the first correction component is variable within the period of the oscillatory motion.
• the defective surface of the reticle and / or the substrate may have a non-uniform course, for example, a non-uniform wavy course.
• the first direction is parallel to the optical axis.
• the second direction is perpendicular to the optical axis.
• the manipulator is designed to simultaneously move the first and the second correction components.
• the manipulator is at least partially disposed in an edge region of the first and / or the second correction component, wherein the edge region is formed outside the aspherical surface contours.
• the manipulator is thus arranged at a distance from the optical action surfaces of the correction arrangement defined by the aspherical surface contours of the correction components.
• an impairment the exposure process in the process of the first and / or the second correction component excluded or at least reduced to a very low level.
• the manipulator has a magnetic arrangement.
• the magnetic arrangement may comprise a magnet, for example a permanent magnet and / or an electromagnet.
• Permanent magnets are advantageous because they can be used without power supply such as power supply.
• electromagnets an electromagnetic force effect can be set with particularly high accuracy, since the strength of the force effect can be varied by regulating the current intensity fed into the coils of the electromagnet. The current can be varied with high accuracy and fast switching cycle. Therefore, the displacement of the first correction component along the first direction on a fast time scale and simultaneously variable with increased accuracy, which is difficult to achieve with conventional mechanical travel drives.
• the magnetic arrangement comprises at least a first magnet and at least one second magnet, wherein the at least one first magnet on the first correction component and the at least one second magnet on the second correction component are arranged.
• At least one magnet is arranged both on the first and on the second correction component.
• the method of the two correction components is thereby particularly effective, so that a desired optical correction effect is set particularly reliably.
• the at least one first magnet and the at least one second magnet may also be arranged with at least partial vertical overlap, so that the magnetic fields of the first and the second magnet may spatially overlap one another.
• a force action between the at least one first Magnet and the at least one second magnet particularly effective, so that the correction effect of the optical correction device according to the invention is further improved.
• the at least one first magnet is a permanent magnet, and / or the at least one second magnet is an electromagnet.
• Such an embodiment has the advantage that only the at least one second magnet needs to be controlled in order to accomplish a relative movement or a displacement between the correction components. This is typically done by applying an electrical voltage to the coil of the electromagnet, which has the additional advantage that the force between the electromagnet and the permanent magnet is particularly accurate adjustable.
• the desired correction effect is particularly precise thanks to the precisely adjustable relative position between the correction components.
• the magnetic arrangement has an annular distribution.
• This measure allows a magnetic force distribution in the region of the annularly distributed magnets, wherein the force distribution is particularly uniform. This promotes high force stability of the optical correction device both in its zero position and in a state in which the correction components are displaced relative to each other.
• the manipulator cooperates with a guide means for guiding the first and / or the second correction component parallel and / or perpendicular to the optical axis.
• the guide means may comprise a sliding guide device.
• the optical correction arrangement comprises a third correction component.
• the mean in the direction of the optical axis correction component may be formed stationary relative to the optical axis.
• at least one electromagnet may be attached to the middle correction component.
• the first, the second and / or the third correction component is held by means of a spring device.
• the spring device has at least one return spring whose spring force is superimposed on the electromagnetic attraction or repulsion force of the magnetic arrangement.
• the magnetic assembly can be held in its zero position or in a state in which the various correction components are displaced relative to each other with increased force stability.
• the restoring force of the spring device can advantageously at least partially compensate the weight force of the first and / or second correction component.
• the manipulator has at least one actuator.
• the at least one actuator is used for moving the first and / or the second correction component in at least one direction.
• the at least one actuator may comprise an ultrasonic motor, a linear motor.
• the at least one actuator may be based on electroactive polymers, plunger coils and / or pressure bellows.
• An inventive projection lens for microlithographic applications has at least one optical correction arrangement according to one or more of the embodiments described above.
• the projection objective can be used, for example, in a microlithographic apparatus according to the invention, in particular a projection exposure apparatus, preferably integrated.
• FIG. 1 shows an optical correction arrangement in a schematic side view
• FIG. 2 shows a further optical correction arrangement in a schematic side view, wherein the optical correction arrangement has a magnetic arrangement
• FIG. 3 shows the optical correction arrangement from FIG. 2, wherein the first correction component is displaced in the direction parallel and perpendicular to the optical axis relative to the second correction component;
• FIG. 4 shows a correction component in a schematic plan view, wherein the correction component has an annular magnetic arrangement;
• FIG. 5 is a schematic side view of another optical correction arrangement having an actuator, the first correction component being displaced in the direction parallel and perpendicular to the optical axis relative to the second correction component;
• FIG. 6 shows a schematic representation of a microlithographic apparatus using the example of a projection exposure apparatus which has a projection objective with an optical correction arrangement.
• an optical correction arrangement generally indicated by reference numeral 10a, is shown in a highly schematized, not to scale side view.
• the optical correction arrangement 10a has a first correction component 12 and a second correction component 14, the first and the second correction components 12, 14 being arranged along an optical axis 16 one behind the other.
• the first correction component 12 is in the direction of the optical axis 16, d. H. in the vertical direction, spaced from the second correction component 14, so that a gap or a gap 17 between the two correction components 12, 14 is formed.
• the first and second correction components 12, 14 are each provided with an aspherical surface contour 18, 20 on their inner side facing the intermediate space 17.
• the aspheric surface contours 18, 20 are designed such that they add at least approximately to zero in a zero position of the optical correction arrangement 10a. In other words, the optical effects of the aspherical surface contours 18, 20 in the zero position of the correction arrangement 10a mutually compensate each other, so that in the zero position of the correction arrangement the exposure light is transmitted at least approximately unchanged by the optical correction arrangement.
• the aspherical surface contours 18, 20 respectively drawn as a wavy contour, which is not limiting for the present invention.
• the first correction component 12 and the second correction component 14 are movable by means of a manipulator M, which is shown schematically here.
• the first correction component 12 is movable parallel to the optical axis 16 in both directions, as illustrated by the double arrow 22.
• the second correction component 14 is perpendicular to the optical axis 16 also movable in both directions, as illustrated by the double arrow 24.
• optical aberrations that occur during the scanning process can be corrected particularly effectively, in contrast to the correction arrangements known from the prior art.
• aberrations such as overlay errors associated with defective surfaces or surface roughnesses of the reticle surface in the object plane and / or the substrate surface in the image plane can be corrected with increased accuracy and reliability.
• a shift of the object plane or the image plane and thus also the focus position of the projection lens is accompanied.
• This undesired shift in the focus position can be compensated by the surfaces of the reticle surface and / or the Substrate surface are measured.
• the measured data can be supplied to the manipulator M for controlling the correction components 12, 14.
• the manipulator M moves the first and / or the second correction component 12, 14 in order to effect a relative movement between the two correction components 12, 14. Because the travel speeds of the first and second correction components can be selected differently from one another, the relative movement generated can advantageously be adapted to the measured surface profile of the reticle or the substrate surface.
• an exemplary basic distance of 100 ⁇ between the surface contours 18, 20 can be adjusted along the optical axis 16 with an exemplary accuracy of 1 ⁇ .
• the first and / or the second correction component 12, 14 can additionally be moved parallel or perpendicular to the optical axis 16.
• FIG. 2 shows a further optical correction arrangement 10b in a schematic side view.
• the optical correction arrangement 10b has all the features of the optical correction arrangement 10a shown in FIG.
• the aspherical surface contours 18, 20 do not extend completely over the respective inner side of the first and the second correction component 12, 14. Instead, the aspheric surface contours 18, 20 are in one of the optical axis 16 outgoing central region of the optical correction assembly 10b so that an edge region 19, 21 of the respective correction component 12, 14 is exposed without aspherization.
• two permanent magnets 30a, 30b are mounted, wherein the two permanent magnets 30a, b are spaced from each other by the aspherical surface contour 18.
• two electromagnets 32 a, b are mounted, which are spaced apart by the aspheric surface contour 20.
• the permanent magnets 30 a, b and the electromagnets 32 a, b are mounted on the inside of the respective correction component 12, 14 facing the gap 17.
• the permanent and electromagnets 30a, b, 32a, b form thus, a magnetic arrangement with two pairs of magnets: the first pair of magnets consists of the permanent magnet 30a and the electromagnet 32a; the second magnet pair consists of the permanent magnet 30b and the electromagnet 32b.
• the first correction component 12 is spaced in the vertical direction from the second correction component 14, wherein the two correction components in the direction perpendicular to the optical axis, d. H. in a horizontal direction, aligned with each other.
• the permanent magnets 30a, b and the electromagnets 32a, b are arranged such that the two magnets of each pair of magnets are overlapped in the vertical direction.
• the magnetic arrangement thus forms a manipulator for moving the first and the second correction component 12, 14.
• a repulsive electromagnetic force effect between the permanent magnet 30a, b and the electromagnet 32a, b of the respective magnet pair used which will be explained in more detail below ,
• the first and second correction components 12, 14 are preferably brought so close to each other vertically that a small gap between the aspheric surface contours 18, 20 is just the process of the second correction component 14 in the horizontal direction 24 allowed.
• This gap (measured along the optical axis 16) corresponds, for example, to the height of the maximum elevation of the aspheric surface contour 18, 20.
• the zero position can be generated by applying a voltage to the electromagnets 32a, b generated repulsive electromagnetic forces between the two magnets of the respective magnet pair be maintained. In this case, the electromagnetic forces counteract the weight force of at least the first correction component 12 and the permanent magnets 30a, b.
• the two correction components 12, 14 In order to produce a desired correction effect, the two correction components 12, 14 must be moved or displaced relative to each other.
• the electrical voltage applied to the electromagnets 32a, b is first is increased or decreased in order to move the first correction component 12 vertically further from the second correction component 16 or closer to it.
• the electrical voltage can be kept constant following the adjustment process.
• the first correction component 12 can also be moved vertically (eg by applying a gradual increase or decrease in electrical voltage) or with a comparatively small and fast "stroke”.
• the second correction component 14 can be deflected horizontally stepwise or with a comparatively large and slow "stroke", wherein the deflection per step / stroke is preferably greater than in the first correction component 12.
• the applied electrical voltage can be calibrated for noise and / or production-related error contributions.
• the same electrical voltage is applied to the two magnet pairs, so that the force components in the horizontal direction equalize in order to avoid accidental horizontal displacement of the second correction component 14.
• the electromagnets 32a, b are preferably activated by means of a control unit, not shown in FIG. 2, which has, for example, a control circuit.
• a control unit not shown in FIG. 2, which has, for example, a control circuit.
• a first guide means 26 for guiding the first correction component 12 in the vertical direction is provided.
• the first guide means 26 is preferably formed as a vertical rail for vertical sliding of the first correction component 12 between two facing sliding surfaces 27a, 27b.
• the sliding surfaces 27a, b extend in the vertical direction, wherein the distance between the sliding surfaces 27a, b substantially corresponds to the width of the first correction component 12. This advantageously ensures that the first correction component 12 can only be moved in the vertical direction.
• the second correction component 14 is, as also shown in FIG. 2, along a second Guide means 28 movable in the horizontal direction.
• the second guide means 28 is preferably designed as a slide extending in the horizontal direction, more preferably as a mechanical plunger.
• FIG. 3 shows the optical correction arrangement 10b from FIG. 2, wherein the first correction arrangement 12 is spaced further from the second correction arrangement 14 in the vertical direction in comparison with the position shown in FIG. 2, which is indicated by the arrow 22 '. is illustrated.
• the second correction component 14 is deflected relative to the first correction component 12 in the horizontal direction along the second guide means 28, which is illustrated by the arrow 24 '. This can be accomplished by applying a higher electrical voltage to one of the two electromagnets 32a, b (here, for example, the electromagnet 32a) than to the other electromagnet (here, for example, the electromagnet 32b).
• the exposure light Upon exposure of a single die of a semiconductor wafer by means of a projection lens, the exposure light is applied to a reticle.
• the light entry point shifts in a first horizontal direction, for example, to traverse the entire width / length of the reticle or a predefined field on the reticle surface.
• the duration of such a scan varies, which may typically be 34 milliseconds (ms).
• a preparation phase for adjusting the optical correction arrangement by means of the manipulator takes place, the preparation phase typically lasting 54 ms. This results in a total exposure time of about 88 ms per die.
• the focus position of the projection lens may shift due to defective surfaces of the reticle and / or the substrate, wherein the shift may be highly variable in time.
• the first correction component 12 is correspondingly rapidly deflected in the vertical direction 22, 22 'by means of the manipulator M. This presupposes that the surface profile of the reticle / substrate has been previously measured and fed to the control unit (not shown here for reasons of clarity) of the manipulator M, so that it deflects the first correction component 12 according to the measured surface profile.
• the deflection during the scanning process can be uniform or uneven, ie with constant or variable speed / acceleration. Also conceivable is an additional deflection of the second correction component 14 in the horizontal direction 24, 24 'during the scanning process.
• the above scanning process In order to scan a plurality of dies on a semiconductor wafer, the above scanning process must be repeated according to the number of dies, and before the scanning step ("scan") of each further die, the projection lens in one
• Step is set again. In this way, the entire wafer can be exposed by means of a "step and scan” method.
• the successive scans for the plurality of dies result in a vibratory motion of the first correction component 12, which is at least approximately periodic. Assuming the above total exposure time of a Dies of 88 ms, results in a frequency of about 1 1, 4 Hz, which is accomplished for example by applying an AC voltage with the same frequency or a periodically variable voltage constant sign. Thus, the vertical displacement of the first correction component 12 relative to the second correction component 14 is advantageously adjusted to the typical scan rhythm.
• further permanent and / or electromagnets may be attached to the optical correction assembly 10b.
• the other permanent and / or Electromagnets on the second correction component 14 facing away from the first correction component 12 are attached.
• at least one of the correction components 12, 14 may be held by means of a spring device.
• the optical correction arrangement 10b may have a third correction component, which is connected downstream, for example, in the direction of the optical axis 16 of the second correction component 14.
• the second correction component 14, which is the mean correction component of the correction arrangement 10b can be arranged in a stationary manner in the vertical direction and / or in the horizontal direction relative to the guide means 26, 28.
• FIG. 4 shows a correction component 13 in a schematic plan view with a viewing direction along the optical axis.
• the correction component 13 may correspond to the first 12 or the second correction component 14 of the optical correction arrangement 10b shown in FIG. 2-3 and has a magnetic arrangement 33.
• the correction component 13 is formed square in the horizontal direction.
• the aspheric surface contours 18, 20 are formed in an optical region 34 indicated by the dashed circle 35 whose center 36 lies on the optical axis.
• the magnetic arrangement 33 is arranged in the edge region 19, 21 of the correction component 13 outside the optical action region 34.
• the magnetic assembly 33 is further formed circular around the center 36.
• the magnetic assembly 33 has eight circular arcuate segments, each segment comprising an outer magnet 33o and an inner magnet 33i.
• the outer magnets 33o form an outer circle, with the inner magnets 33i forming an inner circle concentric with the outer circle.
• the segments are distributed so evenly that their respective circular arc form ⁇ encloses the same angle.
• the manipulator for the process of the first and / or the second correction component may comprise an actuator.
• FIG. 5 shows such an actuator 38a, b for vertically moving the first correction component 12 of a further optical correction arrangement 10c.
• the actuator 38a, b is arranged in the edge region 19 of the first component 12 and extends from a holder 39a, b to the inside of the edge region 19 of the first correction component 12.
• the holder 39a, b is connected to a vertical guide rail and forms with this first guide means 26.
• the actuator 38a, b is preferably fixed at one end to the holder 39a, b, wherein the vertical extent of the actuator 38a, b is variable. As a result, the first correction component 12 can be moved in the vertical direction.
• the actuator 38a, b may comprise an ultrasonic motor, a linear motor, a pressure bellows, an actuator based on electroactive polymers and / or an actuator acting on plunger coils.
• FIG. 6 shows a schematic representation of a microlithographic apparatus which is designed, for example, as a projection exposure apparatus 40.
• the projection exposure apparatus 40 has a light source 42 for generating the exposure light, an illumination optics 44 for guiding the exposure light in the direction of a reticle 54 and a projection objective 46.
• the reticle 54 contains microstructures or nanostructures which are to be imaged on the surface of a substrate 58 by means of the projection objective 46.
• the microstructures or nanostructures define the object plane 56.
• the substrate surface defines the image plane 60. Further, the substrate is supported by a wafer table 62.
• the projection objective 46 has an optical correction arrangement, for example one of the optical correction arrangements 10a, b, c described above, for manipulating the optical wavefront of the exposure light. Furthermore, as shown in FIG. 6, the projection objective 46 has further optical elements, in particular lenses 48, 50, along the optical axis 16.
• the correction components of the optical correction arrangement 10a, b, c can be moved by means of a manipulator (not shown here for reasons of clarity), wherein the manipulator is controlled by a control unit 52. By operating the control unit 52, the various correction components of the optical correction arrangement 10a, b, c can be displaced relative to one another in the vertical or in the horizontal direction. In particular, the correction components can be moved at different speeds.
• imaging aberrations in field and / or pupil imaging in particular field courses of higher order of individual Zernikes (for example Z2 third to fifth order, Z5 first and second order and Z10 first and third order, ...) can be corrected with high accuracy.
• Such corrections lead to a significant reduction of the overlay error.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
• Mounting And Adjusting Of Optical Elements (AREA)
• Optical Elements Other Than Lenses (AREA)
• Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)

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• 2015
  • 2015-09-24 DE DE102015218329.7A patent/DE102015218329A1/de not_active Withdrawn
• 2016
  • 2016-09-06 WO PCT/EP2016/070981 patent/WO2017050565A1/de not_active Ceased
  • 2016-09-06 CN CN201680055946.5A patent/CN108027502B/zh active Active
  • 2016-09-06 KR KR1020187011256A patent/KR102683680B1/ko active Active
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