CN1653359A - Objective with crystal lenses - Google Patents

Abstract

The invention relates to an objective lens, in particular to a projection objective lens with at least one lens made of fluoride crystal used in micro-printing projection exposure equipment. If the lens is provided with an axis of lens (100), the axis is approximately vertical to (100) crystal plane or the crystal plane of fluoride crystal equivalent to the (100) crystal plane, which can reduce the interference of double refraction. If the fluoride crystal lenses are arranged in terms of relative rotation, the objective lens with at least two fluoride crystal lenses can be benefited. The axis of fluoride crystal lens points not only to the (100) crystal plane, but also to (111) crystal plane or (110) crystal plane. A lens group of counter-rotary (100) lenses or counter-rotary (111) lenses or counter-rotary (110) lenses can further reduce the interference of double refraction. An optical component coated with a compensatory coating layer can be configured to further reduce the interference of double refraction.

Description

Object lens with crystalline lens

The present invention relates to a kind of as claim 1 object lens as described in the preamble.

By US 6,201,634 known this projection objectives.Open there, when processing crystal of fluoride lens desirable mode be make lens axis perpendicular alignmnet crystal of fluoride { the 111} crystal face is so that stress birefrin minimizes.US 6,201, and 634 make crystal of fluoride not have the intrinsic birefringence thus.

But the internet publication of being write by John H.Buernett, Eric L.Shirley and the Zachary H.Levine of America NI ST Gaithersburg MD 20899 " Prelminary Determination of an Intrinsic Birefringence inCaF2 " (on May 7th, 01 delivered) is known, and calcium-fluoride single crystal does not have birefringence stress induction, that be intrinsic yet.The content of being introduced is pointed out there, for＜110〉wavelength X=156.1nm of the birefringence produce (6.5 ± a 0.4) nm/cm when to(for) calcium-fluoride of the radiation propagation of crystallographic direction, when wavelength X=193.09nm, produce the birefringence of (3.6 ± a 0.2) nm/cm and the birefringence that when wavelength X=253.65nm, produces (1.2 ± a 0.1) nm/cm.And for＜100〉crystallographic direction and＜111〉the radiation propagation calcium-fluoride of crystallographic direction do not have the intrinsic birefringence, and this point is just foretold as theory.Therefore intrinsic birefringence and direction is closely related and along with the obvious increase that reduces of wavelength.

Below the indication of crystallographic direction symbol＜between provide, and the indication of crystal face provides between symbol { }.Always provide the face normal direction of corresponding crystal face in this crystallographic direction.So crystallographic direction＜100〉expression crystal face { the face normal direction of 100}.Crystal of fluoride belongs to cubic crystal, cubic crystal has host crystal direction＜110 〉,＜110 〉,＜1 10 〉,＜101 〉,＜10 1 〉,＜101 〉,＜10 1 〉,＜011 〉,＜0 11 〉,＜01 1 〉,＜011 〉,＜111 〉,＜11 1 〉,＜1 11 〉,＜11 1 〉,＜1 11 〉,＜111 〉,＜1 11 〉,＜111 〉,＜1 11 〉,＜11 1 〉,＜100 〉,＜010 〉,＜001 〉,＜100 〉,＜0 10〉and＜00 1.Described host crystal direction＜100 〉,＜010 〉,＜011 〉,＜100 〉,＜0 10〉and＜00 1 be that the basis is equivalence mutually with the symmetry characteristic of cubic crystal, the crystallographic direction of therefore pointing to a direction in these host crystal directions below comprises prefix " (100)-".Crystal face perpendicular to a direction in these host crystal directions correspondingly comprises prefix " (100)-".Host crystal direction＜110 〉,＜110 〉,＜1 10 〉,＜101 〉,＜10 1 〉,＜101 〉,＜10 1 〉,＜011 〉,＜011 〉,＜01 1〉and＜01 1 be mutually equivalence equally, the crystallographic direction of therefore pointing to a direction in these host crystal directions below comprises prefix " (110)-".Crystal face perpendicular to a direction in these host crystal directions correspondingly comprises prefix " (110)-".Host crystal direction＜111 〉,＜111 〉,＜1 11 〉,＜11 1 〉,＜111 〉,＜111 〉,＜1 11 〉,＜111 〉,＜1 11〉and＜11 1 be mutually equivalence equally, the crystallographic direction of therefore pointing to a direction in these host crystal directions below comprises prefix " (111)-".Crystal face perpendicular to a direction in these host crystal directions correspondingly comprises prefix " (111)-".In a word, related below above-mentioned host crystal direction is always effective for equivalent host crystal direction.

For example by patent application PCT/EP00/13148 and the document known projection object lens of quoting therein and little printing-apparatus for projection exposure.The embodiment of this application points out that the pure reflection that is fit to and catadioptric projection objective have 0.8 and 0.9 digital lattice ommatidium for the driving wavelength of 193nm and 157nm.

Declare the rotation of also having described the lens element that is used for the compensated birefringence effect in the patented claim of 10055P and date of application 2001.05.15 " apparatus for projection exposure of little printing, optical system and manufacture method " (DE 10123725.1) having volume label.The content of this application also is the application's a part.

The objective of the invention is, a kind of little printing-apparatus for projection exposure projection objective that is used for is provided, wherein greatly reduce the birefringent influence of birefringence, especially intrinsic.

This purpose is achieved according to claim 1,8 and 31 object lens, little printing-apparatus for projection exposure according to claim 47, method that is used to make semiconductor construction according to claim 48, method that is used to make object lens according to claim 49, a method and the lens job operation according to claim 54 that is used for the compensated birefringence effect according to claim 53 by one.

Preferred version of the present invention is provided by the feature of dependent claims.

For the birefringent influence of intrinsic is minimized, claim 1 suggestion, adjust the lens axis like this for the lens of making by fluoride-crystal, when the maximum deviation between lens axis and the host crystal direction less than 5 ° the time, make lens axis and＜100-crystallographic direction overlaps.At this is not that all fluoride-crystalline lens of object lens all must have such crystal face direction.Those lens axis are perpendicular to { lens of 100} crystal face are called (100)-lens below.The lens axis is＜100 〉-orientation on the crystallographic direction has advantage, for＜110-light on the crystallographic direction propagate the birefringent disturbing effect of intrinsic that provides only light ray with great visual angle the time just feel as the lens axis＜111-a orientation on the crystallographic direction.Relevant therewith, the visual angle can be understood as in angle between the outside light ray of lens and this optical axial and the angle between inner this light ray of lens and this lens axis.Like this when the visual angle＜100-crystallographic direction and＜110-angular range between the crystallographic direction in the time, corresponding light ray is just felt the birefringence influence.At this＜110-crystallographic direction and＜100-angle between the crystallographic direction is 45 °.And if light ray aims at＜111 〉-crystallographic direction, then the birefringent disturbing effect of intrinsic just has been felt for less visual angle, because＜110 〉-crystallographic direction and＜111-angle between the crystallographic direction is 35 °.

If described birefringent angle influence for example is to cause that owing to the job operation of crystal of fluoride or mechanical stress, the especially stress birefrin of lens then disclosed solution can be used to reduce birefringent disturbing effect equally.

Said lens axis for example provides by the axis of symmetry of a rotation symmetric lens.If lens do not have the axis of symmetry, then the lens axis can provide by the center of an incident beam or by a straight line, and all light rays are minimum with respect to this ray angle in lens inside.For example can consider lens that reflect or diffraction and have the rectification plate that free forming is corrected face as lens.Also can use surface plate as lens, as long as they are arranged on the light path the inside of object lens.The lens axis of a surface plate is at this lens surface perpendicular to the plane.

But for the preferably rotational symmetric lens of lens.

Described lens have an optical axis that extends to image surface from the object lens face.(100)-lens are that the center constitutes with this optical axis preferably, make lens axis and optical axis coincidence.

Advantageously the present invention can be used for a little printing-apparatus for projection exposure for projection objective, because for this lens resolution has been proposed extra high requirement.But for the check object lens, for example detect by the wave front that measurement has large opening for the lens of projection objective by them, interference effect is played in birefringent influence.

For have big image-side numeral lattice ommatidium, especially greater than 0.7 object lens at the inner visual angle that produces of (100)-lens, they are greater than 25 °, especially greater than 30 °.Big hereto visual angle the present invention just in time plays and makes lens axis alignment＜100 〉-effect of crystallographic direction.If lens axis alignment＜111 〉-crystallographic direction, then light ray is with greater than 25 °, especially produces tangible birefringence disturbing effect greater than 30 ° visual angle, if do not take a following corrective measure.

Because the birefringent disturbing effect of intrinsic can become maximum for 45 ° of visual angles, therefore the design projection objective is favourable like this, and all visual angles that make light ray are less than 45 °, especially smaller or equal to

Wherein NA presentation video side numeral lattice ommatidium and n _FKThe refractive index of expression crystal of fluoride.At this

The result provide the visual angle, when disconnecting on the plane critical surface at light ray, it is corresponding at the image-side of crystal of fluoride lens inside numeral lattice ommatidium.This point by be arranged near the image surface lens have the lens face on the lens face that converges, plane or at most slightly the lens face of micro-scattering be achieved, if the lens face back in scattering produces a stronger lens face that converges in light direction.

For producing near lens main with great visual angle plane on the scene, the especially image surface.Therefore preferably (100)-lens to be contained in a place, plane.To install therein the position of (100)-lens can the scioptics diameter and the ratio of diaphragm diameter determine.Therefore the lens diameter of (100)-lens preferably be to the maximum diaphragm diameter 85%, especially be 80% to the maximum.

Usually be positioned at the nearest lens the inside generation of image surface for the maximum visual angle of projection objective.Therefore for the described lens axis of this lens preferably aim at＜100-crystallographic direction.

The intrinsic birefringence of crystal of fluoride lens is not only depended on the visual angle of a light ray but also is depended on the position angle of this light ray.Therefore can set up a birefringence configuration Δ n (α to each crystal of fluoride lens _L, θ _L), this configuration is a view angle theta on the one hand _LFunction, be azimuth angle alpha on the other hand _LFunction.At this birefringence configuration Δ n for one by view angle theta _LAnd azimuth angle alpha _LThe characteristic that the directions of rays of determining provides the optical path difference of two mutually orthogonal straight line polarized states is used at the ray stroke of crystal of fluoride with the mobile physics of unit [nm/cm].Therefore described intrinsic birefringence and ray path and lens shape are irrelevant.Correspondingly obtain the optical path difference of a ray by the birefringence and the product of the ray path that moves.Described view angle theta _LBetween directions of rays and lens axis, determine described azimuth angle alpha _LIn perpendicular to the crystal face of lens axis the directions of rays of projection with one with reference direction that the fixed logic of lens is connected between determine.

The angular relationship of the birefringence of each crystal of fluoride lens configuration causes a ray that occurs the beam of a picture point at the object lens image surface to obtain the optical path difference Δ OPL (α relevant with angle for two mutually orthogonal polarized states _R, θ _R).At this optical path difference Δ OPL according to view angle theta _LAnd azimuth angle alpha _LProvide.View angle theta at this ray _RDetermine between the optical axis in directions of rays and image surface, and azimuth angle alpha _RDetermine between the reference direction of image surface internal fixation the directions of rays that is projected in image surface and one.If object lens have at least two lens or lens elements of being made by crystal of fluoride now, then advantageously, when host crystal direction of lens orientation of its axis of these lens or lens element and lens or lens element is mutual like this is provided with rotatably around the lens axis, make optical path difference Δ OPL (α _R, θ _R) configuration is compared with a device has the numerical value that greatly reduces, install for the identical host crystal direction of this device lens orientation of its axis and lens or lens element same orientation ground.But, make configuration Δ OPL (α by the lens devices that rotates because the birefringence configuration has an orientation dependence _R, θ _R) maximal value compare with the installation of a same orientation and be reduced to 20%, especially 25%.

About lens element for example is single lens, and it seamlessly is spliced into single lens by bonding optics.Usually lens element is represented the assembly of single lens, and wherein the lens axis of lens element points to the direction of the lens axis of single lens respectively.

Installation fluoride lens by rotation especially can make configuration Δ OPL (α _R, θ _R) to azimuth angle alpha _RDependence obviously reduce, therefore obtain an almost rotational symmetric configuration Δ OPL (α _R, θ _R).

If host crystal direction of lens orientation of its axis, the then birefringence of lens configuration Δ OPL (α _R, θ _R) have a k azimuthal symmetry.For example (100)-lens are pointed in the birefringence configuration, lens orientation of its axis＜100 wherein 〉-crystallographic direction, have 4 azimuthal symmetry, (111)-lens are pointed in the birefringence configuration, lens orientation of its axis＜111 wherein 〉-crystallographic direction, have 3 azimuthal symmetry, and (110)-lens are pointed in the birefringence configuration, lens orientation of its axis＜110 wherein 〉-crystallographic direction, have 2 azimuthal symmetry.Be provided with rotatably around the lens axis with a given rotation angle γ each other according to each lens or lens element in one group of the number of azimuthal symmetry.Measure between the reference direction of per two lens or lens element at this rotation angle γ.For the lens in a group, the host crystal direction that the lens orientation of its axis is identical or one is the host crystal direction of equivalence therewith.The reference direction of the lens in a group is connected with the lens logic like this, makes birefringence configuration Δ n (α _L, θ ₀) for a given view angle theta ₀Has an identical orientation curve.Therefore produce the scope in orientation with greatest birefringence for identical position angle for all lens in a group.Provide by following formula for the rotation angle between per two lens of n lens in a group:

Provide the multiplicity of azimuthal symmetry at this k, n is the number of lenses in a group and m is an arbitrary integer.Such fact ° is considered in error ± 10, and may there be deviation in described rotation angle with theoretic desired angle, so that can consider other boundary condition for the object lens adjustment.Cause to realize best the orientation compensation of the lens light path difference in a group with a deviation of desirable rotation angle.But this point can be tolerated with certain degree.

Therefore provide the predetermined value of following rotation angle for (100)-lens:

If this group comprises two (100)-lens, then the rotation angle between these two lens is 45 ° for lens, perhaps 135 °, and 225 ° ....

Therefore provide the predetermined value of following rotation angle for (111)-lens:

Therefore provide the predetermined value of following rotation angle for (110)-lens:

But at the configuration Δ OPL of this optical path difference (α _R, θ _R) also can provide influence for single group of lens, only consider these lens and suppose that other lens right and wrong are birefringent by calculating for birefringence.

Lens in one group for example determine thus that the aperture ray of the ragged edge of a beam has approximate respectively visual angle in these lens inside, wherein advantageously the visual angle of the aperture ray of ragged edge in these lens inside greater than 15 °, especially greater than 20 °.Aperture ray as ragged edge is called a ray, and it is sent by an object point, and therefore its ray height radius and this ray corresponding to diaphragm in the diaphragm face have an angle according to image-side numeral lattice ommatidium in image surface.Therefore consider the aperture ray of ragged edge for the resolution of lens combination, because they have maximum visual angle usually and obtain maximum interference by birefringence thus in lens inside.Therefore the optical path difference for two mutually orthogonal straight line polarized states of the aperture ray of ragged edge provides conclusion by the maximum interference of birefringent waveplates front really surely.

In addition advantageously, the aperture ray of ragged edge moves an identical ray path respectively in these lens.Obtain being used for orientation summation well balanced of optical path difference configuration by these measures, optical path difference is caused by each lens in a group, so the configuration that optical path difference causes almost is rotational symmetric.

In addition advantageously, the aperture ray of ragged edge each lens the inside in a group obtains the optical path difference of similar size for two mutually orthogonal straight line polarized states for identical lens orientation.If satisfy this condition, when arranging, the lens rotation produces the orientation summation balance an of the best.

The face of same thickness parallel adjacent (100)-or the situation of four parallel adjacent (110)-lens of face of (111)-lens or same thickness under scioptics obtain the rotational symmetric configuration of optical path difference Δ OPL according to above-mentioned formula rotation.Also realize an about rotational symmetric optical path difference configuration for lens by compatibly selecting lens in one group or the thickness by correspondingly selecting lens and radius by the rotation of two lens with curved surface.For (100)-lens and (111)-lens advantageously, one group has two lens.Adjust an about rotational symmetric optical path difference configuration for (110)-lens for four lens in a group.

If lens are adjacent to be provided with, then the rotation of lens is effective especially.Particularly advantageously be a lens separated into two parts and for example seamlessly be spliced into lens element by bonding mutual rotation.

For a projection objective with a plurality of lens advantageously, constitute multiple lens.Lens in this group are provided with rotatably around the lens axis like this, make caused configuration Δ OPL (α _R, θ _R) almost irrelevant with the position angle.

The configuration Δ OPL (α that causes when each group _R, θ _R) because the lens in a group rotate when almost haveing nothing to do with the position angle mutually, can obviously reduce total configuration Δ OPL (α of whole lens thus _R, θ _R) maximal value, described projection objective not only has at least one group of (100)-lens but also has at least one group of (111)-lens.When except one group of (100)-lens, at least one group of (110)-lens being set also, also can realize good compensation in object lens inside.

Described compensation can realize, because birefringence not only has an absolute value but also has a direction.When disposing Δ OPL (α by lens of all (100)-lens combination or the optical path difference that lens element causes _R, θ _R) and by the lens of all (111)-lens or (110)-lens combination or the optical path difference configuration Δ OPL that lens element causes ₂(α _R, θ _R) have approximate equally greatly peaked the time, can realize the compensation of birefringence disturbing effect best.

Another favorable method that reduces the birefringence disturbing effect is to be equipped with a projection objective optical element with compensating coating.Be derived from such knowledge at this, each optical layers for example anti-reflection layer or specular layer itself is also always brought the optical path difference of two mutually orthogonal straight line polarized states except its transmission and reflection characteristic.They are different for s with the p polarization layer and depend on the incident angle of ray to coating.Also there is a kind of birefringence of depending on incident angle.Is rotational symmetric with beam birefringence value and the direction that 0 ° of incident angle produces on compensating coating with respect to central ray for its central ray.Constitute compensating coating like this, make it represent a given characteristic, as a beam ray function of viewing angle about birefringent summation.

At first determine optical path difference configuration Δ OPL (α at this for two mutually orthogonal straight line polarized states of a beam in the projection objective image surface _R, θ _R).The view angle theta of a ray _RBetween the optical axis in directions of rays and the image surface, determine, and azimuth angle alpha _RBetween the fixed reference direction of directions of rays that projects to image surface and image surface inside, determine.At the optical path difference configuration Δ OPL of these two mutually orthogonal straight line polarized states (α _R, θ _R) all have been described owing to crystal of fluoride lens, stress birefrin, be furnished with the intrinsic birefringent influence that the lens optics thereto of anti-reflection layer or specular layer causes.

By optical path difference configuration Δ OPL (α _R, θ _R) determine to be coated to effective birefringence configuration of a compensating coating on the optical element with element axis.For example use lens, surface plate or the mirror of reflection or diffraction as optical element.The optical surface of described optical element by optics utilization district, be that common front end face and rear end face provides.Described element axis for example provides by the axis of symmetry of a rotationally symmetric axis.If lens do not have the axis of symmetry, then the element axis can provide by the center of incident beam or by a straight line, is that the ray angle of all light rays of benchmark is minimum in lens inside with it.Effectively birefringence value depends on the azimuth angle alpha with respect to the reference direction of perpendicular elements axis _FAlso with respect to the view angle theta of element axis _F

Numerical value pair (the α of ray in image surface _R, θ _R) at this corresponding to a numerical value pair (α on optical element _F, θ _F).

Determine effective birefringence configuration of described compensating coating like this, make the optical path difference configuration of two mutually orthogonal straight line polarized states comprise for total system that the configuration of compensating coating is compared obviously with the configuration that does not have compensating coating and reduce.

Described effective compensating coating can be by selecting material, thickness curve and exerting one's influence for the evaporation angle of each coating of compensating coating.Provide coating design and processes parameter at this by using the coating designing computer programs, this program is determined each coating and technological parameter according to effectively birefringence configuration, the material of optical element and the predetermined value of physical dimension.

Can be coated on a plurality of optical elements at this compensating coating.This point improve to be determined the degree of freedom of compensating coating, and these compensating coatings also will guarantee to have higher coating transmissivity except will guaranteeing to compensate.

The Typical Disposition Δ OPL (α of the optical path difference of two mutually orthogonal straight line polarized states _R, θ _R) for view angle theta _RHad small optical path difference at=0 o'clock.If therefore the birefringence effect of compensating coating is for view angle theta _RIt is favourable almost disappearing in=0 o'clock.If when the processing compensating coating, do not use bigger evaporation angle can realize this point.Therefore thereon the optical surface of the optical element of coated compensate coating to have a small as far as possible curvature be favourable.

The birefringent birefringence configuration that also can make compensating coating have a localized variation, therefore generation has the more or less position of phase place division.Not only comprise the variation of phase place division absolute value but also comprise the variation of direction that in this birefringent variation promptly, for example by the given direction relations of main axis orientation, they describe birefringence effect.The birefringence configuration for example can be rotated symmetry with an element axis of being furnished with the element of coating.This for example can stipulate one radially, the increase that promptly defines to the edge or the birefringence of minimizing from the optical element center.Can make compensation effect adapt to the different surfaces curvature of configuration surface best by on purpose controlling radially birefringence configuration.

Also can make birefringence dispose non-rotating symmetry.It can have for example orientation modulation of a birefringence intensity, and especially by a birefringence configuration, it is that benchmark has a plurality of radial symmetry axis with the element axis, especially 2,3,4 or 6 axis of symmetry.For example the modulation of the orientation of a birefringent characteristic with the birefringent substrate of intrinsic can compensate at least partly thus, and for example one by＜110 〉-,＜111 〉-or＜100-substrate that the crystal of fluoride of orientation is made.

The coating of at least one optical surface of the opticator of an optical system also can be made of and coating by way of compensation for example anisotropic coating.Being independent of further feature of the present invention uses and has the element of " anisotropy " coating and be discussed in more detail below.

By have＜100-or＜111-lens of orientation be rotated in the image surface the rotational symmetric configuration Δ OPL (α that obtains an optical path difference that is similar to aforesaid way mutually _R, θ _R), it is only and view angle theta _RRelevant.Described optical path difference can further reduce by the compensating coating of an optical element, and its effective birefringence is configured in primary side only and view angle theta _FRelevant.This point is thick layer by layer by each of compensating coating to be uniformly on optical element and not to have bed thickness to change to be achieved.

Can advantageously use the present invention by making optical element constitute removable element with compensating coating.

It is favourable using from the nearest optical element of image surface at this.

In this present invention's regulation, in first step, determine the optical path difference configuration Δ OPL (α of two mutually orthogonal straight line polarized states for a beam in the image surface _R, θ _R).All optical elements of considering object lens simultaneously comprise the influence of coating.At next step optical element that is equipped with coating at this equally in the light path the inside of beam.

In second step, determine variation in thickness of effective birefringence configuration of a compensating coating and each layer that causes thus and the technological parameter of each layer of processing by stating method.

In the 3rd step, make optical element leave light path and dispose compensating coating.If the optical surface of this optical element is coating, then this coating is being removed before the coating again.The optical element that to be furnished with compensating coating in the 4th step again is arranged to the original position of object lens inside.

In projection objective, preferably use calcium-fluoride as lens material, because it is particularly suitable that the quartz crystal that calcium-fluoride is 193nm for an operation wavelength is used in order to revise color, perhaps provide enough transmissivity for 157nm for operation wavelength.But also is effectively in this conclusion of doing for the crystal of fluoride of strontium-fluoride or barium-fluoride, because crystal has identical cubic crystal type.

When light ray had big visual angle in lens inside, the birefringent disturbing effect of intrinsic can be awared especially.This point for projection objective corresponding to the digital lattice ommatidium of image-side greater than 0.7, especially greater than 0.8 o'clock situation.

Described intrinsic birefringence is along with the reduction of operation wavelength obviously increases.The intrinsic birefringence doubles the wavelength of 248nm for the wavelength of 193nm, for the wavelength of 157nm then 5 times to the wavelength of 248nm.Therefore if when light ray has less than 200nm, especially less than the wavelength of 160nm, can particularly advantageously use the present invention.

For object lens here can be the projection objective of a pure reflection, and it is made of around the lens that optical axis is provided with symmetrically a plurality of rotations, or the projection objective of catadioptric objective type.

These projection objectives can be advantageously used in little printing apparatus for projection exposure, and they comprise structure, a projection objective, a body locating system and a photosensitive substrate of a luminescent system, a mask positioning system, a supporting mask since a light source.

By this little printing apparatus for projection exposure can processing micro structure the semiconductor structure element.

The present invention also provides an appropriate methodology that is used to process object lens.Lens that made by crystal of fluoride according to this method, a host crystal direction of its lens orientation of its axis or lens element are provided with rotatably around the lens axis like this, make configuration Δ OPL (α _R, θ _R) compare with a lens layout and to have the numerical value that reduces especially, for the identical host crystal direction of the lens orientation of its axis of these lens layout crystal of fluoride lens and with identical orientation setting.

This method regulation constitutes lens combination and parallel connection with (100)-lens and (111)-lens or (110)-lens and uses them in addition.For example be applied to a projection objective in this this method, it comprises that at least two crystal of fluoride lens and at least two are＜111 〉-lens on the orientation.At this by these lens position of known reference direction also.This method makes full use of knowledge of the present invention, makes optical path difference configuration Δ OPL (α by the crystal of fluoride lens around the optical axis rotation _R, θ _R) numerical value greatly reduce.Make from the beam of an object point by suitable analogy method and to propagate by projection objective and determine configuration Δ OPL (α in image surface according to the optical characteristics of known crystal of fluoride lens _R, θ _R).Rotation angle between the crystal of fluoride lens is changed so for a long time, have tolerable setting up to birefringence.Also consider other boundary condition in this optimization step, as the lens errors of the non-rotating symmetry of scioptics rotation compensation.Can make configuration Δ OPL (α by this optimization step _R, θ _R) maximal value compare with the projection objective of crystal of fluoride lens same orientation setting and be reduced to 30%, especially be reduced to 50%.Described optimization method also can have an intermediate steps.Form lens combination by the crystal of fluoride lens in this step, wherein the lens in a group produce an approximate optical path difference for the aperture ray of a ragged edge for the lens layout of same orientation between two mutually orthogonal straight line polarized states.Make lens only in the inner rotation of group, to reduce optical path difference in the optimization step below.(100)-lens are rotated like this, make the optical path difference that causes by (100)-lens reduce, (111)-lens are rotated like this, make the optical path difference that causes by (111)-lens reduce.Must realize like this when crystal of fluoride lens being configured on the lens with (100)-orientation and (111)-orientation optimized, make caused (100)-dispose Δ OPL ₁₀₀(α _R, θ _R) and caused (111)-configuration Δ OPL ₁₁₁(α _R, θ _R) compensated as much as possible.Correspondingly also effective for (the 100)-lens and (the 110)-lens of parallel connection use.

The invention still further relates to a kind of method of making lens, wherein in the first step, a plurality of crystal of fluoride plate optics seamlessly are spliced into a plane, in second step, lens are processed by known job operation from the plane.Said plate centers on a face normal and is provided with rotatably each other lens or lens element are described as top.

Its face normal point to identical host crystal direction or almost the plate of the host crystal direction of equivalence have identical axial width in an advantageous manner.

If (100)-plate and (111)-plate optics are seamlessly spliced, then to make (111)-plate thickness and with the thickness of (100)-plate and ratio be 1.5 ± 0.2.

If (100)-plate and (110)-plate optics are seamlessly spliced, then to make (110)-plate thickness and with the thickness of (100)-plate and ratio be 4.0 ± 0.4.

The invention still further relates to the optical element of " anisotropy " coating that has at least one.Especially the coating of at least one optical surface of the optical element of an optical system is made of anisotropic layer and coating by way of compensation for example." anisotropy " on the application's meaning layer is meant a kind of coating, and it demonstrates the tangible direction dependent form of a kind of its optical effect to the electric field intensity direction of the ray that produces in generating plane.Therefore an anisotropic coating has a fast axle and a slow axis in a range of observation, and it is corresponding to a useful direction of coating.

The anisotropic thin film of the known anisotropic properties that has special, the microstructure that can exert one's influence by processing conditions and cause thus.The blastic texture of different very thin films has been described in the article " Play the angles tocreate exotic thin films " that " vacuum melt " 2000/3/4 monthly magazine 26-31 page or leaf is write by M.Weto and M.Brett, they can (glancing angle deposition GLAD) produces under the condition in big deposition angles by evaporation.The very thin film of this porous often has the aciculiform structure, and it has the feature by the decision of coating direction, and the very thin film of this porous also can be used for optical application.For example for the polarization element of this form at I.Hodgkinson and Q.H.Wu at OIC 2000/2001, the the 1st and 2 page article " Review of birefringent and chiral opticalinterference coatings " and I.Hodgkinson and Q.H.Wu are at WorldScientific Singapore, New Jesrsey, London, Hong Kong, provide in the article among the ISBN981-02-2906-2 " Birefringent Thin Film PolarizingElement ", its content is described the basis of content as this.

Anisotropy coating with anisotropy localized variation is particularly suitable for compensation.These variations can comprise the direction and/or because the absolute value of the phase place division that coating produces of polarised direction according to qualifications.

Can adopt all the known cladding process that is suitable for the technological process modification, especially PVD technologies in order to process coating, as electron beam evaporation or sputter with the birefringent birefringence configuration of localized variation.On at least one position of the coating that for a preferred embodiment clad material is coated to substrate surface with a cone of coverage, especially evaporation angle or has existed when producing local anisotropy coating at least, this evaporation angle is arrived greatly and is produced an anisotropic layer structure.By known evaporated device the height distance between material source and the substrate is obviously reduced, to realize the inclination evaporation of a clad material, can be between 30 ° to 40 ° or are bigger in wherein typical evaporation angle for this reason.As the evaporation angle here can be understood as clad material between the face normal of the collision direction of substrate surface and substrate surface in the angle at coating place.

Verified, the suitable remodeling by known diaphragm technology can process on flat, weak bending or strong crooked optical substrate to have definite birefringent characteristic configuration, especially has definite anisotropic anisotropy coating of layer.Carry out following step for a variation in order to control birefringence configuration and/or layer anisotropy.Produce a substrate rotation around the substrate rotation.Preferably use a planar system, wherein each substrate is arranged on the substrate carrier for this reason, and it carries out self rotating and the comprehensive rotation around a main rotating shaft line of planetary system around its substrate axis.Substrate surface passes through the material of a material source with big coating angle coating in this equipment.Realize that at this clad material covering of a time mode is used for producing a coating time of depending on the radial position in coating place according to a given radially time profile during the substrate rotation.Cover and to carry out like this by one or more diaphragms at this, make little coating angle (for example＜30 ° to 35 °) cover, make material only or at least the overwhelming majority on substrate surface, occur with selected direction with very large evaporation angle (for example 40 ° or bigger).Can produce the variation of birefringent any radial symmetry with different anisotropy rates by the suitable shape of diaphragm.

The present invention also relates to a kind of method that is used to make a light polarizing element, i.e. optics component or layout, it has certain effect to the polarized state tool of generation ray, and this element also can be independent of further feature of the present invention to be used and is protected.Described light polarizing element for example can be a delay element (delayer).This method is defined in the coating process and finishes the local birefringence configuration that the back changes a coating.This change can be carried out local assault according to a given space distribution to the coating that machines by the energy that is suitable for the coating morphotropy with and be achieved.Can carry out the local afterwards of coating characteristic for the interference coating system of form of ownership (for example reflection horizon, anti-reflection layer) changes.It is effective especially for anisotropic coating, is the non-equilibrium structure that typically has marginal stability because be responsible for anisotropic morphotropy.With energy load the position really usual practice as realizing by means of one or more masks.The morphotropy of a coating especially can be changed by applying heat affecting.For example by realizing with an infrared laser or other radiation that produces the forms of radiation of enough heat energy.Also can realize above-mentioned processing with an electron irradiation.Also can select or additionally can mechanically apply energy, for example by means of ion irradiation and/or heating drift for thermal energy.Allow to adjust the birefringence configuration of non-rotating symmetry as the back processing of the described layer of special advantage structure, wherein can realize the characteristic adjustment in a very little space in case of necessity, for example with the typical range size of mm or cm scope.

For example coating, the especially anisotropic coating system of evaporation can change its birefringent characteristic partly by laser beam when hanging down coating temperature (cold).Can produce a Polarization filter by this method, it has local phase division modulation targetedly.

The back change of described birefringence configuration also allows to change targetedly its auroral poles characteristic on the projection objective of finishing the optical system of assembling, for example little printing.

Described for this reason optical system can at first be assembled into and measure with an anisotropy coating or another non-equilibrium coating under at least one component condition of use.Effective birefringence that can be obtained at least one desired compensation coating by measurement result is disposed, and it determines that for auroral polesization ground system is essential.Pull down the optical element of being furnished with coating then, so that carry out the back change of layer characteristic partly by suitable adding energy.Described optical system has desired characteristic after the optical element that changes by this way of packing into.Therefore the present invention also relates to a kind of particular method of manufacture that is used for optical system, especially little printing optical system.

Describe the present invention in detail by means of accompanying drawing.

Fig. 1 illustrates one perpendicular to { the lens sectional view together of the crystal of fluoride piece of 100}-crystal face and a projection objective with synoptic diagram;

Fig. 2 A-C with a schematic three dimensional views illustrate each face parallel (100)-, (111)-and (110)-lens;

Fig. 3 illustrates one and is used to define visual angle and azimuthal coordinate system;

Fig. 4 A-F illustrates for the birefringence of (100)-lens configuration with different views, and for two each other with the birefringence configuration of (the 100)-lens of 45 ° of rotations;

Fig. 5 A-F illustrates for the birefringence of (111)-lens configuration with different views, and for two each other with the birefringence configuration of (the 111)-lens of 60 ° of rotations;

Fig. 6 A-G illustrates for the birefringence of (111)-lens configuration with different views, and for two each other with (the 110)-lens of 90 ° of rotations or for four mutually with the birefringence configuration of (the 110)-lens of 45 ° of rotations;

Fig. 7 illustrates the lens sectional view of reflective projection object lens;

Fig. 8 illustrates the lens sectional view of a Catadioptric projection objective;

Fig. 9 illustrates a little printing apparatus for projection exposure with synoptic diagram;

Figure 10 is a curve map, and its expression for one uniformly and the phase place division Δ PH that causes by birefringence for an anisotropic compensating coating and the relation of incident direction;

Figure 11 is a curve map, phase place division Δ PH that its expression causes by birefringence and relation for the incident direction of the coating of individual layer with varying number and different processing conditionss;

Figure 12 letter is illustrated in the Coating installation with planetary system the processing of the anisotropy coating on the lens;

Figure 13 letter illustrates by means of the physical dimension of covering of covering diaphragm processing coating;

Figure 14 letter illustrates the method for a polarizer of a kind of processing, and this polarizer has the back change of an anisotropy coating characteristic.

Fig. 1 letter illustrates the sectional view of a crystal of fluoride piece 3.Select this cross section like this, will { 100}-crystal face 5 be regarded single straight line as, makes therefore that { 100}-crystal face 5 is perpendicular to paper.Described crystal of fluoride piece 3 is as the bright body or the original material of (100)-lens 1.At (100)-lens 1 described in this example is a biconvex lens with lens axis EA, and this lens axis is the axis of symmetry of lens simultaneously.Described lens 1 are processed by the crystal of fluoride piece like this, make lens axis EA perpendicular to { 100}-crystal face.

In Fig. 2 A, represent with a three-dimensional plot, when lens axis EA points to＜100-during crystallographic direction, how relevant with crystallographic direction the intrinsic birefringence is.A parallel plate of being made by calcium-fluoride 201 of circular flat is shown.Described lens axis EA is in this sensing＜100〉crystallographic direction.Except＜100〉crystallographic direction also by arrow illustrate＜101-,＜1 10 〉-,＜10 1 〉-and＜110-crystallographic direction.Schematically by four " lobe " 203 expressions, its surface provides for the birefringent numerical value of the intrinsic of each radiation direction of a light ray in described intrinsic birefringence.Maximum intrinsic birefringence is＜101 〉-,＜1 10 〉-,＜10 1〉and＜110-provide on the crystallographic direction, promptly have 45 ° of visual angles and one 0 °, 90 °, 180 ° and 270 ° of position angles in lens inside for light ray.Provide the birefringent minimum value of intrinsic for 45 °, 135 °, 225 ° and 315 ° of position angles.Disappear for 0 ° of visual angle intrinsic birefringence.

In Fig. 2 B, represent with a three-dimensional plot, when lens axis EA points to＜111-during crystallographic direction, how relevant with crystallographic direction the intrinsic birefringence is.A parallel plate of being made by calcium-fluoride 201 of circular flat is shown.Described lens axis EA is in this sensing＜111〉crystallographic direction.Except＜111〉crystallographic direction also by arrow illustrate＜011-,＜101 〉-and＜110-crystallographic direction.Schematically by three " lobe " 207 expressions, its surface provides for the birefringent numerical value of the intrinsic of each radiation direction of a light ray in described intrinsic birefringence.Maximum intrinsic birefringence is＜011 〉-,＜101 〉-and＜110-provide on the crystallographic direction, promptly have 35 ° of visual angles and one 0 °, 120 ° and 240 ° of position angles in lens inside for light ray.Provide the birefringent minimum value of intrinsic for 60 °, 180 ° and 300 ° of position angles.Disappear for 0 ° of visual angle intrinsic birefringence.

In Fig. 2 C, represent with a three-dimensional plot, when lens axis EA points to＜110-during crystallographic direction, how relevant with crystallographic direction the intrinsic birefringence is.A parallel plate of being made by calcium-fluoride 209 of circular flat is shown.Described lens axis EA is in this sensing＜110〉crystallographic direction.Except＜110〉crystallographic direction also by arrow illustrate＜01 1-,＜10 1 〉-,＜101 〉-and＜011-crystallographic direction.Schematically by five " lobe " 211 expressions, its surface provides for the birefringent numerical value of the intrinsic of each radiation direction of a light ray in described intrinsic birefringence.Maximum intrinsic birefringence provides in lens axis EA direction on the one hand, on the other hand respectively＜01 1 〉-,＜10 1 〉-,＜101〉and＜011-provide on the crystallographic direction, promptly have 0 ° of visual angle or 60 ° of visual angles and four position angles in lens inside for light ray, they are by＜01 1 〉-,＜10 1 〉-,＜101 〉-and＜011-being projected in of crystallographic direction { provide in the 110}-crystal face.But in crystalline material, do not produce with great visual angle this because the refractive index of maximum visual angle by crystal is limited in less than 45 °.

The definition of view angle theta shown in Figure 3 and azimuth angle alpha.For (the 100)-lens among Fig. 2 be illustrated in＜100-z axle on the crystallographic direction, the x axle is by＜110 〉-crystallographic direction is { on the direction that the projection on the 100}-crystal face provides.Be equal to the lens axis and the x axle is equal to reference direction at this z axle.

Known by the internet publication of quoting, for＜110〉ray expansion on the crystallographic direction to measure one be the birefringence value of (6.5 ± 0.4) nm/cm of λ=156.1 o'clock for calcium-fluoride wavelength.Can derive in theory and be subordinated to as canonical parameter with this measured value a calcium-fluoride lens of crystal orientation birefringence configuration Δ n (θ, α).This formula that calculates index ellipsoid by known being used to of crystal optics is drawn the radiation direction of subordinate.Theoretic ultimate principle for example finds under the entry word " crystal optics " in " optics encyclopaedia " (Heidelberg Berlin SpektrumAkademischer publishing house, 1999).

Newer measurement of the present invention draws, for＜110〉radiation expansion on the crystallographic direction is that λ=156.1 an o'clock intrinsic birefringence value is 11m/cm for calcium-fluoride wavelength.Below for canonical parameter Δ n _MaxThe conclusion that=6.5nm/cm draws can be converted to canonical parameter Δ n no problemly _Max=11nm/cm.

Shown in Fig. 4 A for (100)-lens the relation of intrinsic birefringence value and view angle theta during in azimuth angle alpha=0 °.The intrinsic birefringence value of 6.5nm/cm is corresponding to measured value during for view angle theta=45 °.Curve is according to being determined by the known formula of crystal optics.

Shown in Fig. 4 B for (100)-lens the relation of intrinsic birefringence value and azimuth angle alpha during in view angle theta=45 °.Four azimuthal symmetry are obviously visible.

Shown in Fig. 4 C for (100)-lens (θ, α) birefringence of each directions of rays configuration Δ n in the space, angle (θ, α).Every straight line is represented a numerical value and a direction by the directions of rays of view angle theta and azimuth angle alpha definition.The length of straight line and birefringent numerical value or crossing oval main axis length difference are proportional, and the direction of straight line provides the orientation that intersects oval longer main shaft.By obtaining intersecting ellipse with the index ellipsoid of a plane cutting for the direction ray, this plane is perpendicular to directions of rays and pass the center of index ellipsoid.Not only the length of the direction of straight line but also straight line is all represented the tetrad that disposes.The length of straight line and relevant therewith birefringence are maximum for 0 ° at position angle, 90 °, 180 ° and 270 °.

Fig. 4 D illustrates birefringence configuration Δ n, and (θ, α), the birefringence when it provides (100)-lens when the parallel same thickness of two adjacent planar with 45 ° of rotary setting is disposed.Caused birefringence configuration Δ n (θ, α) irrelevant with azimuth angle alpha.The longer main shaft of described crossing ellipse tangentially extends.The optical path difference of caused two mutually orthogonal polarized states obtains by the physical wavelength that birefringence value multiply by at the ray of parallel plane (100)-lens inside.When parallel plane (the 100)-lens of n same thickness are provided with like this, obtain rotational symmetric birefringence configuration, make rotation angle β=90 °/n+m90 ° ± 5 ° between per two lens, wherein n provides the quantity of parallel plane (100)-lens and m is an integer.Reduce 30% when comparing birefringent maximal value with the lens layout of a same orientation for view angle theta=30 °.When all rays of a beam have the angle of approximate size respectively and in that lens are inner when moving equally big wavelength, obtain an almost rotational symmetric configuration of the optical path difference of two mutually orthogonal polarized states for lens arbitrarily.Therefore described lens make up in groups like this, make ray satisfy above-mentioned specified criteria as much as possible.

Relation in (the 100)-lens of the parallel same thickness of two adjacent planar of Fig. 4 D shown in Fig. 4 E intrinsic birefringence value and view angle theta during for α=0 °.Intrinsic birefringence maximal value during in θ=41 ° is 4.2nm/cm and therefore reduces to 6.5nm/cm peaked 35% among Fig. 4 A.

Relation in (the 100)-lens of the parallel same thickness of two adjacent planar of Fig. 4 D shown in Fig. 4 F intrinsic birefringence value and azimuth angle alpha during for θ=41 °.Described intrinsic birefringence and azimuth angle alpha are irrelevant.

Relation in intrinsic birefringence value and the view angle theta during of (111)-lens shown in Fig. 5 A for α=0 °.The intrinsic birefringence value of 6.5nm/cm is corresponding to measured value during in θ=35 °.According to determining curve by the known formula of crystal optics.

Relation in intrinsic birefringence value and the azimuth angle alpha during of (111)-lens shown in Fig. 5 B for θ=35 °.Obvious visible three azimuthal symmetry.

Fig. 5 C with the view of in Fig. 4 C, having quoted illustrate for (111)-lens (θ, α) birefringence of each directions of rays configuration Δ n in the space, angle (θ, α).Not only the length of the direction of straight line but also straight line is all represented the triplets that dispose.The length of straight line and relevant therewith birefringence are maximum for 0 ° at position angle, 120 ° and 240 °.Opposite with (100)-lens, when a ray replaces 0 ° of position angle to pass lens with 180 ° of position angle, the birefringent orientation half-twist.Therefore when the ray angle of a beam between two lens exchanges its symbol, for example can pass through (111)-lens compensation birefringence of two same orientation.

Fig. 5 D illustrates birefringence configuration Δ n, and (θ, α), the birefringence when it provides (111)-lens when the parallel same thickness of two adjacent planar with 60 ° of rotary setting is disposed.Caused birefringence configuration Δ n (θ, α) irrelevant with azimuth angle alpha.But different with Fig. 4 C, intersect oval longer main shaft diameter to extension.The optical path difference of caused two mutually orthogonal polarized states obtains by the physical wavelength that birefringence value multiply by at the ray of (111)-lens inside.When parallel plane (the 111)-lens of n same thickness are provided with like this, obtain rotational symmetric birefringence configuration equally, make rotation angle γ=90 °/k+1120 ° ± 5 ° between per two lens, wherein k provides the quantity of parallel plane (111)-lens and 1 is an integer.Reduce 68% when comparing birefringence value with the lens layout of a same orientation for view angle theta=30 °.When all rays of a beam have the angle of approximate size respectively and in that lens are inner when moving equally big wavelength, also obtain an almost rotational symmetric configuration of the optical path difference of two mutually orthogonal polarized states for lens arbitrarily.Therefore described lens will make up in groups like this, make ray satisfy above-mentioned specified criteria as much as possible.

Relation in (the 111)-lens of the parallel same thickness of two adjacent planar of Fig. 5 D shown in Fig. 5 E intrinsic birefringence value and view angle theta during for α=0 °.Intrinsic birefringence maximal value during in θ=41 ° is 2.8nm/cm and therefore reduces to 6.5nm/cm peaked 57% among Fig. 5 A.

Relation in (the 111)-lens of the parallel same thickness of two adjacent planar of Fig. 5 D shown in Fig. 5 F intrinsic birefringence value and azimuth angle alpha during for θ=41 °.Described intrinsic birefringence and azimuth angle alpha are irrelevant.

If projection objective inner will (100)-lens combination and (111)-lens combination combined, then can compensate the optical path difference of two mutually orthogonal linear states that bring by these lens as much as possible.Require at first to rotate an almost rotational symmetric configuration that realizes optical path difference and two configurations passing through (100)-lens combination and the combined compensation optical path difference of (111)-lens combination at the inside of these groups scioptics for this reason.Make full use of for this reason intersect oval longer main shaft for the orientation of the birefringence configuration of (the 100)-lens combination of a rotation perpendicular to intersecting the orientation of oval longer main shaft for the birefringence configuration of (the 111)-lens combination of a rotation, this point is as being seen by Fig. 4 D and 5D.It is important in this that produce an almost rotational symmetric optical path difference configuration by each group on the one hand, (100)-lens combination summation is numerically almost the same big with (111)-lens summation on the other hand.

Relation in intrinsic birefringence value and the view angle theta during of (110)-lens shown in Fig. 6 A for azimuth angle alpha=0 °.The intrinsic birefringence value of 6.5nm/cm is corresponding to measured value during in θ=0 °.According to determining curve by the known formula of crystal optics.

Relation in intrinsic birefringence value and the azimuth angle alpha during of (110)-lens shown in Fig. 6 B for θ=35 °.Obvious visible two azimuthal symmetry.

Fig. 6 C with the view of in Fig. 4 C, having quoted illustrate for (110)-lens (θ, α) birefringence of each directions of rays configuration Δ n in the space, angle (θ, α).Not only the length of the direction of straight line but also straight line all demonstrates two one group of property of configuration.Provide the straight line of maximum length and relevant therewith greatest birefringence during for view angle theta=0 °.

Fig. 6 D illustrates birefringence configuration Δ n, and (θ, α), the birefringence when it provides (110)-lens when the parallel same thickness of two adjacent planar with 90 ° of rotary setting is disposed.(θ α) has four azimuthal symmetry to caused birefringence configuration Δ n.Occurring maximum birefringence value when azimuth angle alpha-45 °, 135 °, 225 ° and 315 °, is 2.6nm/cm when wherein birefringence value is for view angle theta=40 °.

Fig. 6 E illustrates birefringence configuration Δ n, and (θ, α), it provides the combination when (the 110)-lens of (the 110)-lens of the same thickness of two parallel plane Fig. 6 C and two parallel plane same thickness.Rotation angle between per two (110)-lens is 45 °.Caused birefringence configuration Δ n (θ, α) irrelevant with azimuth angle alpha.But different with Fig. 4 C, intersect oval longer main shaft diameter to extension, promptly with the collocation approximation of Fig. 5 C.The optical path difference of caused two mutually orthogonal polarized states obtains by the physical wavelength that birefringence value multiply by at the ray of (110)-lens inside.When parallel plane (the 110)-lens of 4n same thickness are provided with like this, obtain rotational symmetric birefringence configuration equally, make rotation angle β=45 °/n+m90 ° ± 5 ° between per two lens, wherein 4n provides the quantity of parallel plane (100)-lens and m is an integer.When all rays of a beam have the angle of approximate size respectively and in that lens are inner when moving equally big wavelength, also obtain an almost rotational symmetric configuration of the optical path difference of two mutually orthogonal polarized states for lens arbitrarily.Therefore described lens will make up in groups like this, make ray satisfy above-mentioned specified criteria as much as possible.

Relation in (the 110)-lens of the parallel same thickness of four adjacent planar of Fig. 6 E shown in Fig. 6 F intrinsic birefringence value and view angle theta during for azimuth angle alpha=0 °.Intrinsic birefringence value during in view angle theta=41 ° is 1.0nm/cm and therefore reduces to 6.5nm/cm peaked 84% among Fig. 5 A.

Relation in (the 110)-lens of the parallel same thickness of four adjacent planar of Fig. 6 E shown in Fig. 6 G intrinsic birefringence value and azimuth angle alpha during for θ=41 °.Described intrinsic birefringence and azimuth angle alpha are irrelevant.

If projection objective inner will (110)-lens combination and (100)-lens combination combined, then can compensate the optical path difference of two mutually orthogonal linear states that bring by these lens as much as possible.Require at first to rotate an almost rotational symmetric configuration that realizes optical path difference and two configurations passing through (110)-lens combination and the combined compensation optical path difference of (100)-lens combination at the inside of these groups scioptics for this reason.Make full use of for this reason intersect oval longer main shaft for the orientation of the birefringence configuration of (the 110)-lens combination of a rotation perpendicular to intersecting the orientation of oval longer main shaft for the birefringence configuration of (the 100)-lens combination of a rotation, this point is as being seen by Fig. 4 D and 6E.It is important in this that produce an almost rotational symmetric optical path difference configuration by each group on the one hand, (110)-lens combination summation is numerically almost the same big with (100)-lens summation on the other hand.

A lens cross section that reflective projection object lens wavelength is 157nm shown in Figure 7.The optical data of object lens is concentrated in table 1 and is provided hereto.Present embodiment can by obtain among patent application PCT/EP00/13148 and corresponding to the there Fig. 7 or table 6.For the principle of work of describing object lens in more detail sees also patent application PCT/EP00/13148.All lens of these object lens are made by calcium-crystal of fluoride.These object lens are 0.9 at the digital lattice ommatidium of image-side.Revise the imaging efficiency of these object lens so well, make with the deviation of the wave front of an ideal ball ripple be that benchmark is less than 1.8m λ with the wavelength of 157nm.Just in time require to reduce as much as possible for example birefringent disturbing effect of intrinsic for this efficient object lens.

Calculate the view angle theta and the light path RL of the aperture ray 609 of ragged edge for each lens L601 to L630 for the embodiment of Fig. 7 _LFrom the object point of coordinate x=0mm and y=0mm and to have one image surface be the angle of benchmark with the optical axis, it is corresponding to the digital lattice ommatidium of image-side at this for the aperture ray 609 of ragged edge.Therefore consider the aperture ray 609 of ragged edge, because almost draw maximum visual angle in lens inside for it.

Lens	View angle theta [°]	Light path RL L[mm]	Optical path difference (111)-lens α L＝0°[mm]	Optical path difference (111)-lens α L＝60°[mm]	Optical path difference (111)-lens α L＝0°[mm]	Optical path difference (100)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝0°[mm]	Optical path difference (110)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝90°[mm]	Optical path difference (110)-lens α L＝135°[mm]
											L601	????8.1	????15.1	????2.9	????-2.2	????-0.8	????-0.4	????-9.0	????-9.0	????-9.1	????-9.0
L602	????8.7	????8.2	????1.7	????-1.2	????-0.5	????-0.2	????-4.9	????-4.8	????-4.9	????-4.8
											L603	????7.8	????9.5	????1.7	????-1-3	????-0.4	????-0.2	????-5.7	????-5.7	????-5.7	????-5.7
L604	????10.7	????7.2	????1.9	????-1.3	????-0.6	????-0.3	????-4.1	????-4.1	????-4.1	????-4.1
											L605	????9.4	????6.5	????1.5	????-1.0	????-0.4	????-0.2	????-3.8	????-3.8	????-3.8	????-3.8
L606	????10.3	????8.5	????2.1	????-1.4	????-0.7	????-0.3	????-4.8	????-4.8	????-4.8	????-4.8
											L607	????21.8	????12.7	????6.6	????-2.7	????-3.9	????-1.8	????-4.2	????-4.2	????-4.3	????-4.2
L608	????25.4	????22.2	????12.8	????-4.4	????-8.7	????-3.9	????-5.3	????-5.7	????-5.8	????-5.7
											L609	????16.3	????36.1	????14.3	????-7.6	????-6.8	????-3.3	????-16.5	????-16.5	????-16.7	????-16.5
L610	????12.2	????15.2	????4.5	????-2.9	????-1.7	????-0.8	????-8.2	????-8.2	????-8.2	????-8.2
											L611	????2.3	????26.6	????1.4	????-1.3	????-0.1	????-0.1	????-17.2	????-17.2	????-17.2	????-17.2
L612	????2.3	????32.2	????1.6	????-1.5	????-0.1	????-0.1	????-20.8	????-20.8	????-20.8	????-20.8
											L613	????-18.3	????30.4	????-6.6	????13.5	????-7.0	????-3.3	????-12.5	????-12.6	????-12.7	????-12.6
L614	????-18.7	????22.0	????-4.8	????10.0	????-5.3	????-2.5	????-8.9	????-8.9	????-9.0	????-8.9
											L615	????-14.0	????10.2	????-2.0	????3.5	????-1.5	????-0.7	????-5.1	????-5.1	????-5.2	????-5.1
L616	????-1.3	????29.8	????-0.8	????0.9	????0.0	????0.0	????-19.3	????-19.3	????-19.3	????-19.3
											L617	????26.4	????31.6	????18.6	????-6.1	????-13.0	????-5.7	????-6.7	????-7.6	????-7.5	????-7.6
L618	????33.5	????14.3	????9.3	????-2.0	????-7.9	????-3.1	????-0.6	????3.2	????-1.4	????3.2
											L619	????26.5	????7.5	????4.4	????-1.4	????-3.1	????-1.4	????-1.6	????-1.8	????-1.8	????-1.8
L620	????19.3	????6.4	????3.0	????-1.4	????-1.6	????-0.8	????-2.5	????-2.5	????-2.5	????-2.5
											L621	????6.7	????8.0	????1.3	????-1.0	????-0.3	????-0.1	????-4.9	????-4.9	????-4.9	????-4.9
L622	????-10.3	????7.7	????-1.3	????1.9	????-0.6	????-0.3	????-4.4	????-4.4	????-4.4	????-4.4
											L623	????-11.9	????9.6	????-1.8	????2.8	????-1.0	????-0.5	????-5.2	????-5.2	????-5.2	????-5.2
L624	????0.3	????17.8	????0.1	????-0.1	????0.0	????0.0	????-11.6	????-11.6	????-11.6	????-11.6
											L625	????6.0	????16.3	????2.3	????-1.8	????-0.5	????-0.2	????-9.9	????-9.9	????-10.0	????-9.9
L626	????-24.0	????9.0	????-1.9	????5.0	????-3.2	????-1.5	????-2.5	????-2.6	????-2.6	????-2.6
											L627	????-35.6	????8.0	????-0.9	????5.2	????-4.7	????-1.7	????0.1	????2.1	????-0.5	????2.1
L628	????-39.4	????12.0	????-1.0	????7.6	????-7.5	????-2.5	????1.0	????4.0	????-0.3	????4.0
											L629	????-35.3	????27.3	????-3.3	????17.7	????-15.7	????-5.9	????0.5	????6.9	????-1.9	????6.9
L630	????-35.3	????26.0	????-3.1	????16.9	????-15.0	????-5.6	????0.4	????6.5	????-1.9	????6.5
											Summation			????64,5	????42,3	????112,9	????47,4	????-198.2	????-178.7	????-208.0	????-178.8

Table 2

For the aperture ray of ragged edge except view angle theta and light path RL _LProvide the optical path difference of two mutually orthogonal straight line polarized states to concentrate in the external table 2 for different lens orientation.For (111)-lens, (100)-lens and the establishment of (110)-lens optical path difference, the wherein azimuth angle alpha of ragged edge marginal ray _LIs 0 ° and 60 ° in lens inside for (111)-lens, is 0 ° and 45 ° and be 0 ° for (110)-lens for (100)-lens, 45 °, and 90 ° and 135 °.

Can be drawn by table 2, view angle theta is for lens L608, and L617, L618, L619, L627, L628, L629 and L630 be greater than 25 °, for L618, and L619, L627, L628, L629 and L630 even greater than 30 °.With relevant especially with great visual angle be to be positioned at the nearest L627 to L630 of image surface.

Realized making the maximum visual angle of all light rays less than 45 ° by the projection objective design.Maximum visual angle for the aperture ray of lens L628 ragged edge is 39.4 °.It is useful directly using two thick planar lens L629 and L630 before image surface.

Diaphragm diameter between lens L621 and L622 is 270mm.The diameter of lens L618 is 207mm and the diameter of lens L627 to L630 is 190mm.Therefore these have with great visual angle lens diameter less than 80% of diaphragm diameter.

As can be seen from Table 2, it is favourable being orientated on (100)-direction with big visual angle for each lens, because birefringence value is lower generally.Its reason is, for (100)-lens＜110 〉-influence of crystallographic direction is only for bigger angle be felt the same with (111)-lens.For example for lens L608, the described optical path difference of L609 and L617 is low more than 30%.

Can represent well that by means of two plane parallel lens L629 and L630 mutual rotation that how can scioptics obviously reduces birefringence.Two lens have identical visual angle for 35.3 ° ragged edge aperture ray and the approximate light path of 27.3mm or 26.0mm.If two lens same orientation ground that are made of (100)-lens are installed, then will be obtained the optical path difference of a 30.7nm.But when two (100)-lens rotated 45 ° relatively, then optical path difference was reduced to 20.9nm, promptly reduced 32%.If two lens same orientation ground that are made of (111)-lens are installed, then will be obtained the optical path difference of a 34.6nm.But when two (111)-lens rotated 60 ° relatively, then optical path difference was reduced to 13.6nm, promptly reduced 61%.

If lens L629 splits into L6291 and L6292 and lens L630 splits into lens L6301 and L6302, then can realize the almost completely compensation of the optical path difference of two mutually orthogonal straight line polarized states according to the intrinsic birefringence that causes by lens L629 and L630, wherein lens L6291 is that a thickness is 9.15mm (100)-lens, lens L6292 is that a thickness is 13.1mm (111)-lens, lens L6301 is that a thickness is 8.33mm (100)-lens, and lens L6302 is that a thickness is 12.9mm (111) one lens.45 ° of the relative rotations of lens L6291, and 60 ° of relative rotations of lens L6292 with L6302 with L6301.Caused in this case maximum optical path difference is 0.2nm.Described lens L6291 the same with L6292 and lens L6301 with L6302 can optics seamlessly, for example by bonding splicing.When projection objective includes only a crystalline lens, also can use this principle.These lens are divided at least two lens, and they are provided with the relative rotation.By bonding realization splicing.Other method is at first each planar optics of desired crystal orientation seamlessly to be connected and is processed in another processing step the lens of mutual splicing.

The method that another scioptics L629 and L630 reduce intrinsic birefringence disturbing effect is, lens L629 splits into L6293 and L6294 and lens L630 splits into lens L6303 and L6304, wherein lens L6293 is that a thickness is 11.13mm (110)-lens, thickness of lens L6294 is (110)-lens of 11.13, lens L6303 is that a thickness is 10.62mm (110)-lens, and lens L6304 is that a thickness is 10.62mm (110)-lens.Lens L6293 and L6294 and lens L6303 and the relative half-twist of L6304 difference, wherein the rotation angle between lens L6293 and the L6303 is 45 °.Caused in this case maximum optical path difference is 4.2nm.Described lens L6293 the same with L6294 and lens L6303 with L6304 can optics seamlessly, for example by bonding splicing.

When each lens splits into three lens element L6295, L6296 and L6297 and L6305, when L6306 and L6307, then almost completely realize because the compensation of the optical path difference of the lens L629 of high load capacity and two mutually orthogonal linear states that L630 causes, wherein lens L6295 is that a thickness is 4.45mm (100)-lens, lens L6296 and L6297 are that a thickness is 8.90 (110)-lens, lens L6305 is that a thickness is 4.25mm (100)-lens, and lens L6306 and L6307 are that a thickness is 8.49mm (110)-lens.45 ° of the relative rotations of lens L6294 with L6304, per two lens L6295, L6297,45 ° of the relative rotations of L6306 with L6307.Caused maximum optical path difference is reduced to below the 0.1nm in this combination.Lens L6295 to L6297 the same with lens L6305 to L6307 can optics seamlessly, for example by bonding splicing.

The method that another scioptics L629 and L630 reduce intrinsic birefringence disturbing effect is to make two (110)-lens and (100)-combination of lenses.Two (110)-lens are installed with 90 ° each other rotatably at this, and the rotation angle between (100)-lens and (the 110)-lens is 45 °+m90 °, and wherein m is an integer.Lens L629 is split into L6298 and L6299 for this reason and lens L630 is split into lens L6308 and L6309, wherein lens L6298 is that a thickness is 17.40mm (110)-lens, lens L6299 is that a thickness is 4.87mm (110)-lens, lens L6308 is that a thickness is 12.53mm (110)-lens, and lens L6309 is that a thickness is 8.70mm (100)-lens.Caused maximum optical path difference is 3.1nm.Described lens L6298 the same with L6299 and lens L6308 with L6309 can optics seamlessly, for example by bonding splicing.

A catadioptric projection objective 711 shown in Figure 8 is the lens cross section of 157nm for wavelength.The optical data of object lens is concentrated in table 3 and is provided hereto.Present embodiment can by obtain among patent application PCT/EP00/13148 and corresponding to the there Fig. 9 or table 8.For the principle of work of describing object lens in more detail sees also patent application PCT/EP00/13148.All lens of these object lens are made by calcium-crystal of fluoride.These object lens are 0.8 at the digital lattice ommatidium of image-side.

Calculate the view angle theta and the light path RL of the aperture ray 715 of the aperture ray 713 of top ragged edge and bottom ragged edge for each lens L801 to L817 for the embodiment of Fig. 8 _LFrom the object point of coordinate x=0mm and y=0mm and to have one image surface be the angle of benchmark with the optical axis, it is corresponding to the digital lattice ommatidium of image-side at this for the aperture ray 713 of ragged edge and 715.Calculate the aperture ray of upper and lower ragged edge, leave the thing field of axis and therefore aperture ray and optical axis are asymmetricly extended, just as the situation of the aperture ray of the ragged edge of Fig. 7 embodiment because relate to one.

In table 4, provide the top ragged edge the aperture ray data and in table 5, provide the data of the aperture ray of bottom ragged edge.For the aperture ray of ragged edge except view angle theta and light path RL _LProvide the optical path difference of two mutually orthogonal straight line polarized states with in external table 4 and the table 5 for different lens orientation.For (111)-lens, (100)-lens and (110)-lens establishment optical path difference; And be used for (111)-lens, (100)-lens and (110)-lens, the wherein azimuth angle alpha of ragged edge marginal ray _LIs 0 ° and 60 ° in lens inside for (111)-lens, is 0 ° and 45 ° and be 0 ° for (110)-lens for (100)-lens, 45 °, and 90 ° and 135 °.

Lens	View angle theta [°]	Light path RL L[mm]	Optical path difference (111)-lens α L＝0°[mm]	Optical path difference (111)-lens α L＝60°[mm]	Optical path difference (100)-lens α L＝0°[mm]	Optical path difference (100)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝0°[mm]	Optical path difference (110)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝90°[mm]	Optical path difference (110)-lens α L＝135°[mm]
											????801	????1.4	????28.1	????0.8	????-0.8	????0.0	????0.0	????-18.2	????-18.2	????-18.2	????-18.2
????802	????-10.8	????30.7	????-5.3	????8.0	????-2.7	????-13	????-17.2	????-17.2	????-17.3	????-17.2
											????803	????-15.6	????32.4	????-6.8	????12.4	????-5.7	????-2.7	????-15.3	????-15.3	????-15.4	????-15.3
????803	????-24.4	????31.8	????-6.5	????17.8	????-11.7	????-5.2	????-8.4	????-8.8	????-9.0	????-8.8
											????802	????-19.5	????26.6	????-5.8	????12.4	????-6.8	????-3.2	????-10.2	????-10.3	????-10.4	????-10.3
????804	????6.4	????20.1	????3.0	????-2.4	????-0.6	????-0.3	????-12.4	????-12.4	????-12.4	????-12.4
											????805	????10.8	????34.4	????9.0	????-6.0	????-3.0	????-1.5	????-19.3	????-19.3	????-19.3	????-19.3
????806	????0.2	????10.0	????0.1	????-0.1	????0.0	????0.0	????-6.5	????-6.5	????-6.5	????-6.5
											????807	????-11.1	????22.0	????-3.9	????5.9	????-2.1	????-1.0	????-12.2	????-12.2	????-12.3	????-12.2
????808	????0.1	????18.5	????0.0	????0.0	????0.0	????0.0	????-12.0	????-12.0	????-12.0	????-12.0
											????809	????-0.8	????9.0	????-0.1	????0.2	????0.0	????0.0	????-5.8	????-5.8	????-5.8	????-5.8
????810	????1.1	????12.4	????0.3	????-0.3	????0.0	????0.0	????-8.0	????-8.0	????-8.0	????-8.0
											????811	????-16.8	????9.4	????-2.0	????3.8	????-1.9	????-0.9	????-4.2	????-4.2	????-4.2	????-4.2
????812	????-10.4	????29.8	????-5.0	????7.5	????-2.4	????-1.2	????-16.9	????-16.9	????-16.9	????-16.9
											????813	????-8.8	????34.7	????-5.2	????7.3	????-2.1	????-1.0	????-20.5	????-20.5	????-20.5	????-20.5
????814	????-9.4	????17.5	????-2.8	????4.0	????-1.2	????-0.6	????-10.2	????-10.2	????-10.2	????-10.2
											????815	????-27.4	????28.1	????-5.3	????16.9	????-12.2	????-5.3	????-5.2	????-6.4	????-6.1	????-6.4
????816	????-28.7	????40.2	????-7.1	????24.8	????-18.6	????-7.9	????-6.2	????-8.5	????-7.6	????-8.5
											????817	????-30.8	????39.0	????-6.3	????24.7	????-19.6	????-8.1	????-3.9	????-8.0	????-5.7	????-8.0
Summation			????-48.9	????136.1	????-90.9	????-40.3	????-212.9	????-220.9	????-218.0	????-220.9

Table 4

Lens	View angle theta [°]	Light path RL L[mm]	Optical path difference (111)-lens α L＝0°[mm]	Optical path difference (111)-lens α L＝60°[mm]	Optical path difference (the 100)-sub-α of lens L＝0°[mm]	Optical path difference (100)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝0°[mm]	Optical path difference (110)-lens α L＝45°[mm]	Optical path difference (110)-lens α L＝90°[mm]	Optical path difference (110)-lens α L＝135°[mm]
											????801	????-11.6	????32.1	????-5.8	????9.0	????-3.2	????-1.6	????-17.6	????-17.6	????-17.6	????-17.6
????802	????19.5	????28.3	????13.3	????-6.1	????-7.3	????-3.4	????-10.9	????-10.9	????-11.1	????-10.9
											????803	????24.7	????33.8	????19.1	????-6.9	????-12.7	????-5.7	????-8.6	????-9.2	????-9.3	????-9.2
????803	????17.7	????34.3	????14.7	????-7.4	????-7.5	????-3.6	????-14.6	????-14.6	????-14.8	????-14.6
											????802	????12.7	????31.6	????9.7	????-6.0	????-3.8	????-1.8	????-16.7	????-16.7	????-16.8	????-16.7
????804	????-5.2	????27.7	????-2.7	????3.3	????-0.6	????-0.3	????-17.4	????-17.4	????-17.4	????-17.4
											????805	????-4.5	????34.6	????-3.0	????3.5	????-0.5	????-0.3	????-21.9	????-21.9	????-21.9	????-21.9
????806	????-8.6	????19.5	????-2.9	????4.0	????-1.1	????-0.6	????-11.6	????-11.6	????-11.6	????-11.6
											????807	????-0.5	????16.5	????-0.2	????0.2	????0.0	????0.0	????-10.7	????-10.7	????-10.7	????-10.7
????808	????-8.2	????25.6	????-3.7	????5.0	????-1.3	????-0.7	????-15.3	?????-15.3	????-15.3	????-15.3
											????809	????-7.5	????10.1	????-1.3	????1.8	????-0.4	????-0.2	????-6.1	????-6.1	????-6.1	????-6.1
????810	????-9.1	????13.1	????-2.0	????2.9	????-0.8	????-0.4	????-7.7	????-7.7	????-7.7	????-7.7
											????811	????9.0	????9.9	????2.1	????-1.5	????-0.6	????-0.3	????-5.8	????-5.8	????-5.8	????-5.8
????812	????2.6	????30.7	????1.8	????-1.6	????-0.2	????-0.1	????-19.8	????-19.8	????-19.8	????-19.8
											????813	????0.9	????34.0	????0.6	????-0.6	????0.0	????0.0	????-22.1	????-22.1	????-22.1	????-22.1
????814	????1.3	????10.4	????0.3	????-0.3	????0.0	????0.0	????-6.7	????-6.7	????-6.7	????-6.7
											????815	????23.5	????16.3	????8.9	????-3.4	????-5.7	????-2.6	????-4.7	????-4.8	????-4.9	????-4.8
????816	????24.6	????37.2	????21.0	????-7.6	????-13.9	????-6.2	????-9.6	????-10.2	????-10.3	????-10.2
											????817	????29.4	????29.6	????18.5	????-5.1	????-14.1	????-5.9	????-4.0	????-6.2	????-5.2	????-6.2
Summation			????88.3	????-16.8	????-73.7	????-33.5	????-231.9	????-235.4	????-235.2	????-235.4

Table 5

Can draw by table 4 and table 5, view angle theta for lens L815 to L817 greater than 25 °.Be positioned at the nearest lens L815 to L817 of image surface in this embodiment and have big visual angle.Design by projection objective L815 to L817 realized making maximum visual angle smaller or equal to

Maximum visual angle for the aperture ray of lens L817 ragged edge is 30.8 °.

Diaphragm diameter between lens L811 and L812 is 193mm.The diameter of lens L815 to L817 is all less than 162mm.Therefore these diameters with lens with great visual angle are all less than 85% of diaphragm diameter.

Can be drawn by table 4 and table 5, be favourable for lens to be orientated on (100)-direction with great visual angle, because birefringence value is littler generally.For example low more than 20% for lens L815 to L817 optical path difference.

Embodiment by means of Fig. 8 will point out below, how can compensate the intrinsic birefringence as much as possible by parallel use (100)-lens combination of rotating mutually and (the 111)-lens combination of rotating mutually.

At first all calcium-fluorides being installed in does not have on (111)-orientation that (111)-lens rotate mutually.Produce maximum optical path difference in this case for two mutually orthogonal straight line polarized states of 136nm.Can make maximum optical path difference be reduced to about 38nm by rotation (111)-lens.Lens L801 and L804 are formed a group and lens L802 and L803 are formed another group for this reason, wherein the rotation angle between the lens is respectively 60 °.Lens L808, L809 and L810 and lens L815, L816 and L817 respectively form one three lens combination, and the rotation angle between wherein per two lens is 40 °.Lens L811, L812, relative rotation angle of L813 and L814 composition is 30 ° four lens combination.

Do not have then to obtain maximum optical path difference on (100)-orientation that (100)-lens rotate mutually if all calcium-fluorides are installed in for two mutually orthogonal straight line polarized states of 90.6nm.Can make maximum optical path difference be reduced to about 40nm by rotation (100)-lens.Lens L801 and L804 are formed a group and lens L802 and L803 are formed another group for this reason, wherein the rotation angle between the lens is respectively 45 °.Lens L808, L809 and L810 and lens L815, L816 and L817 respectively form one three lens combination, and the rotation angle between wherein per two lens is 30 °.Lens L811, L812, relative rotation angle of L813 and L814 composition is 22.5 ° four lens combination.

If with (100)-lens combination and the combination of (111)-lens combination, then can obtain the maximum optical path difference of two mutually orthogonal straight line polarized states.Lens L801 and L804 are formed (111)-lens combination, wherein the rotation angle between the lens is 60 ° for this reason.Lens L802 and L803 are formed (100)-lens combination, and wherein the rotation angle between the lens is 45 °.With lens L808, L809 and L810 form three lens combination of (100)-lens, and the rotation angle between wherein per two lens is 30 °.With lens L811, L812, L813 and L814 form four lens combination of (111)-lens, and wherein the rotation angle between the lens is 22.5 °.The lens axis of lens L805 in groups and L807 is not＜111 〉-be orientated on the crystallographic direction, and lens L806 is＜100 〉-be orientated on the crystallographic direction.All groups can at random be provided with around optical axis each other rotatably.This rotary freedom can fully be used for the compensation of the aberration that for example scioptics of non-rotating symmetry focus on to produce.

To point out by means of reflecting objective 611 below, how by arranging that an optical element with compensating coating 612 obviously reduces the disturbing effect of birefringence effect.For this considers the birefringence summation of two lens L629 and L630, they are made and therefore demonstrate the intrinsic birefringence by calcium-fluoride.Two lens have one (111)-orientation and in this embodiment each other with 60 ° of rotations.Realize an almost rotational symmetric optical path difference Δ OPL configuration thus.For the aperture ray maximum optical path difference Δ OPL of a ragged edge according to azimuth angle alpha _RBetween 13.6nm to 14.6nm.On the optical surface of the lens L630 that faces image surface 0 ', be coated in the compensating coating 613 described in the table 6.This compensating coating 613 is made up of 15 layers of independently being made by magnesium-fluoride (GgF2) and lanthanum-fluoride (LaF3) material.N and k provide refractive index real number and imaginary part in table 6.Bed thickness is the thickness curve that does not have side direction uniformly.Evaporation angle during the coating is perpendicular to the optical surface of lens L630.By compensating coating caused optical path difference is added up to 1.1nm and therefore compares obvious reduction with the object lens that do not have compensating coating.

Coating	Thickness [nm]	Material
				Substrate	?CaF2
????1	????103.54	?MgF2
			????2	????41.54	?LaF3
????3	????33.35	?MgF2
			????4	????30.8	?LaF3
????5	????39.53	?MgF2
			????6	????35.34	?LaF3
????7	????32.05	?MgF2
			????8	????27.25	?LaF3
????9	????28.57	?MgF2
			????10	????26.48	?LaF3
????11	????27.64	?MgF2
			????12	????26.17	?LaF3
????13	????27.36	?MgF2
			????14	????26.11	?LaF3
????15	????8.66	?MgF2

Optical constant	????n	????k
			LaF3	????1.760026	????0.00118471
MgF2	????1.506675	????0.00305275

Table 6

If replace latter two lens to consider whole object lens, can realize that is also similarly carried out a mode.Replace a birefringence also can design a plurality of optical elements with compensating coating by a compensating coating optical element.

For compensated birefringence in a total system also can be used this method, wherein this birefringent reason may be stress birefrin, intrinsic birefringence and the birefringence that caused by other layer.

Finally adjust the back in system and determine the optical path difference Δ OPL configuration of one or more beams in image surface.Calculating essential compensating coating by a coating optimization procedure also for example is coated on the nearest system surfaces of image surface.If it is favourable can changing from the nearest optical element of image surface.So also can revise and have only the birefringence effect that just produces by the object lens operation.

In order to compensate the crystal birefringence among the UV, can the crystal element with different crystal axle orientation be set ground, front and back as mentioned above.If ground is provided with the lens with different crystal direction before and after in an optical system, then have problems, multiple lens is with different angle transmissions, and then compensation can only realize limitedly.Compensation for this form of optical system that only contains a crystalline lens can not realize at all.

A solution is, with the counterrotating lens of two divisions of the structurally bonding one-tenth of lens.In fact this method is born the stress that makes the path distortion and two halfbodies are laterally located with the micron precision.

Suggestion processing by mutually bonding, be orientated the bright body that counterrotating single plate is made with respect to crystal axis, they are by milling and be polished to lens.All foregoings about orientation also are effective at this.

Except typical bonding (wringing) of optical system processing, also can realize all other splicing and included by the present invention with inner contact and small as far as possible stress adding.Described bonding especially can be supported by the coating of for example making by quartz glass.Importantly, do not produce the refraction or the reflection of interference at stitching position.

Realize the selection that is orientated according to above-mentioned rule.

Provide bright body as embodiment, can process the lens L816 of the projection objective that is used for Fig. 8 by it.The aspheric layer radius that these lens L816 has a projection is that the front of 342.13mm and the layer radius of a recessed sphere are the back side of 449.26mm.Axial width is 37.3mm.Lens material is calcium-fluoride.Lens diameter is 141mm.Must have the total thickness of 45mm and the diameter of 150mm at least by its bright body that will process lens.Said bright body can be formed with thick (the 111)-plate of the 13.5mm of 60 ° of rotations with thick (the 100)-plate of the 9.0mm of 45 ° of rotations and two each other each other by two, and their optics seamlessly splices.(100)-plate and (111)-plate will be adjacent to respectively be provided with at this.

Six seamlessly to be spliced with thick (the 111)-plate optics of the 4.5mm of 60 ° of rotations each other with thick (the 100)-plate of the 3.0mm of 45 ° of rotations and six each other in another embodiment, wherein respectively at two (111)-plates of two (100)-plate back linkings.

Four seamlessly will be spliced with thick (the 100)-plate optics of the 4.5mm of 45 ° of rotations each other with thick (the 110)-plate of the 9.0mm of 45 ° of rotations and two each other in another embodiment, wherein two (100)-plates are connected on four (111)-plates.

Eight seamlessly to be spliced with thick (the 100)-plate optics of the 2.25mm of 45 ° of rotations each other with thick (the 110)-plate of the 4.5mm of 45 ° of rotations and four each other in another embodiment, wherein be connected two (100)-plates respectively four (110)-plate back.

The theory structure of a little printing apparatus for projection exposure is described by means of Fig. 9.Described apparatus for projection exposure 81 has a light-emitting device 83 and projection objective 85.This projection objective 85 comprises a lens devices 819, and it has an aperture diaphragm AP, wherein optical axis 87 of scioptics device 89 definition.In Fig. 6 and Fig. 7, provide the embodiment of lens devices 89.A mask 89 is set between light-emitting device 83 and projection objective 85, and it is fixed on the light path the inside by a mask fixed body 811.The mask 89 that is used for little printing like this has a micron-nanometer structure, and it for example is imaged on the image surface 813 with coefficient 4 or 5 by projection objective 85 with dwindling.Fix a photosensitive substrate 815, for example a substrate by a substrate support 817 location in image surface 813 the insides.

Still the minimal structure that can offer an explanation depends on the image-side numeral lattice ommatidium of the wavelength X that is used for luminous light and projection objective 85, and 81 highest resolutions that can realize of wherein said apparatus for projection exposure are along with the wavelength X of light-emitting device 83 reduces to improve with the increase of the digital lattice ommatidium of image-side of projection objective 85.By can realize resolution at the embodiment shown in Fig. 6 and Fig. 7 less than 150nm.Therefore the intrinsic birefringence is minimized.By the present invention the intrinsic birefringence is directly reduced greatly for the disturbing effect of the projection objective with big image-side numeral lattice ommatidium.

By means of Figure 10 the birefringent influence of a compensating coating anisotropy to working by coating described.Provide by the phasing degree Δ PH that phase place divides by birefringent absolute value and direction that coating works at this, promptly provide by the difference in the wave front between two mutually orthogonal straight line polarized states.This parameter also is suitable for describing birefringent direction relations.Provide the relation of phasing degree and ray incident angle in Figure 10, this incident angle is corresponding to the visual angle Θ of above-mentioned view.The phase place division is shown, and it is applied to an anisotropy on the planar substrate by one and interferes layer system (magnesium fluoride-lanthanum fluoride alternative layer combination) to work, and this layer system is with one 40 ° evaporation angle evaporations.This layer system is by an isotropic layer system balance.

The curve of representing with HOM in the centre provides the measured value for compensating coating 613 that provide, isotropic in table 6, its bed thickness is uniformly and does not have horizontal variation in thickness.As what stated, effective refraction of coating characterizes by phase place division, during in visual angle Θ=0 ° approximately zero.Mobile slightly to negative value for bigger visual angle owing to the light path that amplifies obtains a phase place division in layer inside.Continuous straight line illustrates and is used to be incident on a measured value perpendicular to the ellipsometry in first plane of clad surface, and this plane is called 0 °-plane here.Dotted line provides the numerical value for 90 ° perpendicular-plane.As can be seen, the numerical value of phase place division and direction are irrelevant with position angle basically.Therefore relate to an isotropic coating.

And demonstrate the directional dependence of the division of tangible phase place and position angle for anisotropic coating (AN).0 ° of measurement of incidence direction value that is illustrated in first plane of curve A N, this plane is corresponding to 0 ° of position angle.Compare with uniform coating and to demonstrate substantially the same angle curve, but birefringent numerical value obviously strengthens, wherein when 0 ° of incident angle, also present a tangible phase place division (about 10 °).When on the first identical plane when with the optical axis being the opposed direction incident of benchmark, obtain substantially the same numerical value.This point is benchmark Rotate 180 ° (180 ° of curve A N) with the direction of measurement corresponding to test specimen.

And in being incident on a plane vertical with first plane time (90 ° of curve A N), wherein the position angle although then present identical phase place division according to numerical value, has negative phasing degree with 90 ° of variations.Therefore proof, by means of an anisotropy coating can the control phase division direction, process one and has a given anisotropy coating of polarised direction according to qualifications, this direction field vector with respect to the electricity of incident ray on an assigned direction is orientated.

Describe by means of Figure 11, for anisotropic coating also on purpose the degree of control phase division, be birefringent intensity.Measured value is shown for phase place division and the relation of visual angle Θ for different coating.Corresponding to a MgF2/LaF3-alternating layer group with 8 independent stratums, they are with 150 ℃ of evaporations in this diamond indicia.The square mark is corresponding to a coating with the independent stratum with 6 this materials of uniform temp processing.The relatively expression of the birefringence effect of these two kinds of layer systems, the absolute value of attainable phase place division increases along with the increase of coating quantity.

Triangular marker is corresponding to a coating with 8 layers, and they are with 250 ℃, i.e. obvious higher temperature coating.Obtain significantly lower phase place division with comparing accordingly with 8 layers of 150 ℃ of coating.

This trend (the birefringence effect is strengthened along with the increase of number of plies amount, and birefringent effect weakens along with the increase of processing temperature) by with other layer system (six layer systems under the room temperature, the two layer system under 220 or 150 ℃) more also be tangible.

With the exemplary pass that illustrates is that the effectively optical element of polarization can be realized by means of anisotropic coating in the basis, and it has the birefringence of a given localized variation on numerical value and direction by the surface of coating.The processing of the rotation symmetry anisotropy coating of describing lens by means of Figure 12 in an evaporated device with planetary system.This planetary system has (unshowned) main support around 500 rotations of a main rotating shaft, arranges a plurality of substrate supports 502 around each substrate support axle 501 rotation on its circumference.Each substrate support has a substrate 503, and it is made of biconvex lens in example.At the main rotating shaft place material source 504 that is used for deposition material is set, be used for for example making magnesium fluoride and lanthanum fluoride by means of electron ray evaporation and evaporation to the substrate clad surface 505 that is positioned at the material source opposite.Biao Shi clad material occurs with an evaporation angle (coating angle) in each coating place by a dotted line, and this angle is determined by the physical dimension of equipment and the curvature of clad surface.

In order in this equipment, to produce an anisotropic coating 510, one of numerical value covers the seat of diaphragm 511 between material source 504 and substrate, cover diaphragm by this clad surface in the face of material source is partly covered with respect to material stream fully, the clad surface part that therefore only deviates from material source is with big evaporation angle coating.

The inclination evaporation play make layer material at one by effect oblique perverse symbolic expression, that grow in the aciculiform structure.Determine by main evaporation direction at this vergence direction.Manifesting of this morphotropism can be exerted one's influence by the coating temperature, and wherein anisotropy is for lower coating temperature, for example be compared to higher temperature as surpassing 120 ℃ for the temperature of room temperature between about 90 ℃, and 150 ℃ or 200 ℃ manifest more consumingly.

Obviously, can produce one and turning axle 501 rotational symmetric anisotropic coating by this method, wherein polarised direction (vergence direction of clad material post) is basic according to qualifications points to radially.Change because the curvature of minute surface also obtains an evaporation angle from the center to the edge, wherein this angle from inside to outside increases in example, so the anisotropy of coating is stronger at the center at the edge ratio.Opposite for recessed character of surface.It is evident that also can adjust the center of gravity that incident angle distributes by the height distance of adjusting between material source 504 and the coating, wherein less vertical range causes bigger evaporation angle.

By means of Figure 13 how to describe by for each coating place suitably cover mechanism of diaphragm provide one by coating place radial position decision according to the coating time of given radially time profile and the angular spectrum of a desired aciculiform structural growth direction.The bridging effect of described diaphragm is symbolically passed through diaphragm 511 ' at this, 511 "; 511 illustrate; they are at substrate 503 '; 503 ", 503 are around turning axle 501 ', 501 ", cover the substrate of the rotation of back in the time mode with respect to material source material stream 520 during 501 rotation by the arrow representative.

Figure 13 (a) illustrates one and has covering of a constant shield angle on entire radius, and this shield angle is measured on the circumferencial direction of rotation.This point realizes by the V-arrangement " window " in the material stream.This cover play make the coating time, promptly be positioned at material flow 520 inner loop around time in coating place for the essentially identical effect of all radial positions.Substrate surface this point for the plane causes a uniform as far as possible diametrically structure.For example outwards expand according to dotted line 515 if cover window, then provide a radially time profile, the position specific diameter in the middle of wherein radially being positioned at is to the position crested more longways that is positioned at the outside.Can realize a compensation that reduces towards the edge bed thickness that causes by geometric condition thus where necessary.But also can produce rotational symmetric layer, its bed thickness increases from the centre to the continuous edge.Narrow more by the evaporation direction scope of covering the diaphragm permission, the angular spectrum of aciculiform structural growth direction is just narrow or more little more.At this narrower angular spectrum usually corresponding to a stronger anisotropy.

The position that position specific diameter in the middle of being positioned on rectangular window in Figure 13 (b) plays and makes radially upwards is positioned at the outside on the longer time interval with the effect of evaporation under the condition of more different directions.Can produce coating where necessary thus, its bed thickness therefrom mind-set the edge and is reduced to reduce more consumingly than a thickness that only causes by surface curvature.And anisotropy at the edge than manifesting more consumingly at the center.Can between center and edge, realize a uniform bed thickness by this method where necessary for recessed coating face.

Diaphragm 511 geometric configuratioies in Figure 13 (c) play effect that the centre 525 that makes substrate 503 places material stream constantly and therefore coating isotropically basically.Obtain one at all the other positions and have the anisotropy of variation diametrically and/or the radial variations of bed thickness.

By suitable selection deposition material stream is the direction that the orientation of benchmark can be adjusted the coating main shaft with the diaphragm.If for example for according to being arranged in and going up evaporation with 90 ° of directions that are misplaced (dotted arrow) of Figure 13 (a), then produce the aciculiform structure, they are tangential orientation basically.

For filth such as hydrocarbon, water vapour or similar substance being difficult to or avoiding entering the layer structure of porous, can apply a protective seam, for example as the outermost layer of coating as the atresia as far as possible of diffusion fence.This layer can constitute optically by suitable bed thickness as far as possible neutrally, for example is made of semiconductor.

Describe a method modification by means of Figure 15, it can process the effective parts of auroral polesization (as delayer), and it has the local birefringence that almost can freely select and distributes.At first to a substrate, effective coating 551 of auroral polesization of parallel plane plate 550 configurations for example, its birefringence effect can be even substantially or anisotropic for this reason.Described coating has a non-equilibrium layer structure, and it allows by the blastic texture of autotelic partial accession energy change layer and changes it thus at the birefringent characteristic that loads the position.That works as example is that produce by the inclination evaporation, an anisotropy coating 551.Working position according to layer 551 loads layer partly by an energy according to a given distribution, this energy is suitable for changing the birefringent characteristic that blastic texture also changes layer material thus.For this reason in example the enough ray 552 of energy, for example ion irradiation or one suitably the perforate 553 of passing a mask 554 of the laser beam of expansion incide coating.Inducing a blastic texture variation of supporting diffusion by mask aperture 553 given 555 the insides, coating position thus, wherein for example the aciculiform growth structure of an anisotropy coating condenses and forms a thicker layer and a more small anisotropy.Also can successively use a plurality of masks of different hole shapes, to produce complicated local birefringence configuration.Also can realize not having masking method, for example by " write " a desired birefringence configuration by means of the enough rays of the energy of a focusing, for example laser beam.Can produce almost arbitrarily the local modulation of the phase place division of working by this method by a coating.Consistent phase place site of cleavage can be very little space, and for example several microns are big.

Under the condition of using the anisotropy original layers, can produce polarization mask (being polarizer or delay element) by this method with effect relevant with the position for different wavelength range in all objects front.For example can produce by " cold evaporation " for the original layers of visible wavelength region, wherein change can be by enough for example the producing from the radiation of the laser beam of UV scope of energy for blastic texture.For using in the UV scope, especially must stablizing with respect to operation wavelength for the described original layers of the wavelength below the 260nm.Be, to produce heat-staple coating thus what this suited with higher coating temperature, as 100 to 152 ℃ of generation original layers.The distortion of blastic texture realizes essential the adding by corresponding big energy, for example by infrared laser, by ion irradiation, electron ray or by suitable heating drift.

The phase shift mask that described method also is suitable for processing polarization especially uses at least one anisotropy coating as the effective parts of auroral polesization.For example can make the anisotropy coating that for example limits on space of a straight line configuration near the position that will form structure directly at this, so that produce favourable delayed-action.The phase shift mask of polarization (polarized phase shiftmasks, P:PSM) structure and working method for example at article " Polarized Phase ShiftMasks:Concept; Design; and Potential Advantages toPhotolithography Process and Physical Design " (by R.Wang, W.Grobmann, A.Reich and M.Thompson write, Proc.SPIE Vol.4562 406ff) the middle description, its disclosure is incorporated in this instructions.Can avoid or prevent " phaseconflict " problem by means of this mask, therefore can realize a disposable exposure for the imaging of enough quality in case of necessity.

Table 1

157.629nm?????????1/2

Refractive index when exposing the radius thickness glass

The mirror diameter

---------------------------------------------------------------------------------------

--

0??????????0.000000000???????????27.171475840????????N2????????1.00031429????????46.200

0.000000000???????????0.602670797?????????N2????????1.00031429????????52.673

L601???????900.198243311AS???????15.151264556????????CaF2??????1.55929035????????53.454

-235.121106435????????9.531971079?????????N2????????1.00031429????????54.049

L602???????-167.185917779????????8.294716452?????????CaF2??????1.55929035????????54.178

-132.673519510????????14.020355779????????N2????????1.00031429????????54.901

L603???????-333.194586652????????9.893809820?????????CaF2??????1.55929035????????53.988

-155.450516203????????15.930502944????????N2????????1.00031429????????54.132

L604???????-73.572316296?????????7.641977580?????????CaF2??????1.55929035????????53.748

-68.248613899AS???????2.881720302?????????N2????????1.00031429????????55.167

L605???????-86.993585564AS???????5.094651720?????????CaF2??????1.55929035????????52.580

-238.150965327????????5.379130780?????????N2????????1.00031429????????53.729

L606???????-165.613920870????????5.094651720?????????CaF2??????1.55929035????????53.730

153.417884485?????????34.150169591????????N2????????1.00031429????????56.762

L607???????-92.061009990?????????5.094651720?????????CaF2??????1.55929035????????58.081

8491.086261873AS??????19.673523795????????N2????????1.00031429????????74.689

L608???????-407.131300451????????30.380807138????????CaF2??????1.55929035????????87.291

-140.620317156????????0.761662684?????????N2????????1.00031429????????91.858

L609???????-4831.804853654AS?????50.269660218????????CaF2??????1.55929035????????117.436

-192.197373609????????1.688916911?????????N2????????1.00031429????????121.408

L610???????-367.718684892????????21.227715500????????CaF2??????1.55929035????????127.704

-233.628547894????????2.224071019?????????N2????????1.00031429????????129.305

L611???????709.585855080?????????28.736922725????????CaF2??????1.55929035????????137.016

1238.859445357????????9.120684720?????????N2????????1.00031429????????137.428

L612???????1205.457051945????????49.281218258????????CaF2??????1.55929035????????138.288

-285.321880705????????1.625271224?????????N2????????1.00031429????????138.379

L613???????137.549591710?????????56.718543740????????CaF2??????1.55929035????????108.652

-4380.301012978AS?????0.623523902?????????N2????????1.00031429????????106.138

L614???????2663.880214408????????6.792868960?????????CaF2??????1.55929035????????103.602

149.184979730?????????15.779049257????????N2????????1.00031429????????84.589

L615???????281.093106064?????????6.792868960?????????CaF2??????1.55929035????????83.373

184.030288413?????????32.341552355????????N2????????1.00031429????????77.968

L616???????-222.157416308????????5.094651720?????????CaF2??????1.55929035????????77.463

101.254238115AS???????56.792634221????????N2????????1.00031429????????71.826

L617???????-106.960638018????????5.094651720?????????CaF2??????1.55929035????????72.237

1612.305471130????????20.581065398????????N2????????1.00031429????????89.760

L618???????-415.596135628????????26.398111993????????CaF2??????1.55929035????????96.803

-204.680O44631????????0.713343960?????????N2????????1.00031429????????103.409

L619???????-646.696622394????????25.867340760????????CaF2??????1.55929035????????116.636

-231.917626896????????0.766268682?????????N2????????1.00031429????????118.569

L620???????-790.657607677????????23.400482872????????CaF2??????1.55929035????????128.806

-294.872053725????????0.721402031?????????N2????????1.00031429????????130.074

L621???????786.625567756?????????40.932308205????????CaF2??????1.55929035????????141.705

-431.247283013????????12.736629300????????N2????????1.00031429????????142.089

0.000000000???????????-8.491086200????????N2????????1.00031429????????134.586

1622???????295.022653593AS???????20.165109438????????CaF2??????1.55929035????????139.341

449.912291916?????????0.619840486?????????N2????????1.00031429????????137.916

L623???????358.934076212?????????48.662890509????????CaF2??????1.55929035????????136.936

-622.662988878????????30.955714157????????N2????????1.00031429????????135.288

L624???????-224.404889753????????12.736629300????????CaF2??????1.55929035????????134.760

-251.154571510AS??????16.079850229????????N2????????1.00031429????????134.853

L625???????-193.582989843AS??????16.510083506????????CaF2??????1.55929035????????134.101

-198.077570749????????0.880353a72?????????N2????????1.00031429????????136.109

L626???????206.241795157?????????19.927993542????????CaF2??????1.55929035????????101.240

338.140581666?????????0.925956949?????????N2????????1.00031429????????97.594

L627???????111.017549581?????????24.560089962????????CaF2??????1.55929035????????85.023

169.576109839?????????0.777849447?????????N2????????1.00031429????????81.164

L628????????117.982165264??????31.161065630??????CaF2?????1.55929035????????75.464

921.219058213AS????6.934980174???????N2???????1.00031429????????69.501

L629????????0.000000000????????22.260797322??????CaF2?????1.55929035????????63.637

0.000000000????????4.245543100???????N2???????1.00031429????????48.606

L630????????0.000000000????????21.227715500??????CaF2?????1.55929035????????41.032

0.000000000????????8.491086200???????N2???????1.00031429????????26.698

0.000000000????????0.000000000????????????????1.00000000????????11.550

Provide wavelength and refractive index with respect to vacuum

Non-spherical constant

The non-sphere of lens L601

K?????0.0000

C1????1.28594437e-007

C2????8.50731836e-013

C3????1.16375620e-016

C4????2.28674275e-019

C5????-1.23202729e-022

C6????3.32056239e-026

C7????-4.28323389e-030

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L604

K????-1.3312

C1????-4.03355456e-007

C2????2.25776586e-011

C3????-2.19259878e-014

C4????4.32573397e-018

C5????-7.92477159e-022

C6????7.57618874e-026

C7????-7.14962797e-030

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L605

K????-1.1417

C1????1.33637337e-007

C2????1.56787758e-011

C3????-1.64362484e-014

C4????3.59793786e-018

C5????-5.11312568e-022

C6????1.70636633e-026

C7????1.82384731e-030

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L607

K?????0.0000

C1????1.34745120e-007

C2????-2.19807543e-011

C3????1.20275881e-015

C4????4.39597377e-020

C5????-2.37132819e-023

C6????2.87510939e-027

C7????-1.42065162e-031

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L609

K?????0.0000

C1????6.85760526e-009

C2????-4.84524868e-013

C3????-6.28751350e-018

C4????-3.72607209e-022

C5????3.25276841e-026

C6????-4.05509974e-033

C7????-3.98843079e-035

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L613

K?????0.0000

C1????2.24737416e-008

C2????-4.45043770e-013

C3????-4.10272049e-017

C4????4.31632628e-021

C5????-3.27538237e-025

C6????1.44053025e-029

C7????-2.76858490e-034

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L616

K?????0.0000

C1????-2.83553693e-008

C2????-1.12122261e-011

C3????-2.05192812e-016

C4????-1.55525080e-020

C5????-4.77093112e-024

C6????8.39331135e-028

C7????-8.97313681e-032

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L622

K?????0.0421

C1????7.07310826e-010

C2????-2.00157185e-014

C3????-9.33825109e-020

C4????1.27125854e-024

C5????1.94008709e-027

C6????-6.11989858e-032

C7????2.92367322e-036

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L624

K?????0.0000

C1????3.02835805e-010

C2????-2.40484062e-014

C3????-3.22339189e-019

C4????1.64516979e-022

C5????-8.51268614e-027

C6????2.09276792e-031

C7????-4.74605669e-036

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L625

K?????0.0000

C1????-3.99248993e-010

C2????5.79276562e-014

C3????3.53241478e-018

C4????-4.57872308e-023

C5????-6.29695208e-027

C6????1.57844931e-031

C7????-2.19266130e-036

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L628

K?????0.0000

C1????4.40737732e-008

C2????1.52385268e-012

C3????-5.44510329e-016

C4????6.32549789e-020

C5????-4.58358203e-024

C6????1.92230388e-028

C7????-3.11311258e-033

C8????0.00000000e+000

C9????0.00000000e+000

Table 3

157.13nm??????????1/2

Refractive index when exposing the radius thickness glass

The mirror diameter

-----------------------------------------------------------------------------------

----

0???????0.000000000????????????34.000000000????????????????1.00000000????????82.150

0.000000000????????????0.100000000?????????????????1.00000000????????87.654

L801????276.724757380??????????40.000000000?????CaF2???????1.55970990????????90.112

1413.944109416AS???????95.000000000????????????????1.00000000????????89.442

SP1????0.000000000????????????11.000000000????????????????1.00000000????????90.034

0.000000000????????????433.237005445???????????????1.00000000????????90.104

L802????-195.924336384?????????17.295305525?????CaF2???????1.55970990????????92.746

-467.658808527?????????40.841112468????????????????1.00000000????????98.732

L803????-241.385736441?????????15.977235467?????CaF2???????1.55970990????????105.512

-857.211727400AS???????21.649331094????????????????1.00000000????????118.786

SP2?????0.000000000????????????0.000010000?????????????????1.00000000????????139.325

253.074839896??????????21.649331094????????????????1.00000000????????119.350

L803′??857.211727400AS????????15.977235467?????CaF2???????1.55970990????????118.986

241.385736441??????????40.841112468????????????????1.00000000????????108.546

L802′??467.658808527??????????17.295305525?????CaF2???????1.55970990????????102.615

195.924336384??????????419.981357165???????????????1.00000000????????95.689

SP3?????0.000000000????????????6.255658280?????????????????1.00000000????????76.370

0.000000000????????????42.609155219????????????????1.00000000????????76.064

Z1??????0.000000000????????????67.449547115????????????????1.00000000????????73.981

L804????432.544479547??????????37.784311058?????CaF2???????1.55970990????????90.274

-522.188532471?????????113.756133662???????????????1.00000000????????92.507

L805????-263.167605725?????????33.768525968?????CaF2???????1.55970990????????100.053

-291.940616829AS???????14.536591424????????????????1.00000000????????106.516

L806????589.642961222AS????????20.449887046?????CaF2???????1.55970990????????110.482

-5539.698828792????????443.944079795???????????????1.00000000????????110.523

L807????221.780582003??????????9.000000000??????CaF2???????1.55970990????????108.311

153.071443064??????????22.790060084????????????????1.00000000????????104.062

L808????309.446967518??????????38.542735318?????CaF2???????1.55970990????????104.062

-2660.227900099????????0.100022286?????????????????1.00000000????????104.098

L809????23655.354584194????????12.899131182?????CaF2???????1.55970990????????104.054

-1473.189213176????????9.318886362?????????????????1.00000000????????103.931

L810????-652.136459374?????????16.359499814?????CaF2???????1.55970990????????103.644

-446.489459129?????????0.100000000?????????????????1.00000000????????103.877

L811????174.593507050??????????25.900313780?????CaF2???????1.55970990????????99.267

392.239615259AS????????14.064505431????????????????1.00000000????????96.610

0.000000000????????????2.045119392?????????????????1.00000000????????96.552

L812????7497.306838492?????????16.759051656?????CaF2???????1.55970990????????96.383

318.210831711??????????8.891640764?????????????????1.00000000????????94.998

L813????428.724465129??????????41.295806263?????CaF2???????1.55970990????????95.548

3290.097860119AS???????7.377912006?????????????????1.00000000????????95.040

L814????721.012739719??????????33.927118706?????CaF2???????1.55970990????????95.443

-272.650872353?????????6.871397517?????????????????1.00000000????????95.207

L815????131.257556743??????????38.826450065?????CaF2???????1.55970990????????81.345

632.112566477AS????????4.409527396?????????????????1.00000000????????74.847

L816????342.127616157AS????????37.346293509?????CaF2???????1.55970990????????70.394

449.261078744??????????4.859754445?????????????????1.00000000????????54.895

L817????144.034814702??????????34.792179308?????CaF2???????1.55970990????????48.040

-751.263321098AS???????11.999872684????????????????1.00000000????????33.475

0′?????0.000000000????????????0.000127776?????????????????1.00000000????????16.430

Non-spherical constant

The non-sphere of lens L801

K?????0.0000

C1????4.90231706e-009

C2????3.08634889e-014

C3????-9.53005325e-019

C4????-6.06316417e-024

C5????6.11462814e-028

C6????-8.64346302e-032

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L803

K?????0.0000

C1????-5.33460884e-009

C2????9.73867225e-014

C3????-3.28422058e-018

C4????1.50550421e-022

C5????0.00000000e+000

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L803 '

K?????0.0000

C1????5.33460884e-009

C2????-9.73867225e-014

C3????3.28422058e-018

C4????-1.50550421e-022

C5????0.00000000e+000

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L805

K?????0.0000

C1????2.42569449e-009

C2????3.96137865e-014

C3????-2.47855149e-018

C4????7.95092779e-023

C5????0.00000000e+000

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L806

K?????0.0000

C1????-6.74111232e-009

C2????-2.57289693e-014

C3????-2.81309020e-018

C4????6.70057831e-023

C5????5.06272344e-028

C6????-4.81282974e-032

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L811

K?????0.0000

C1????2.28889624e-008

C2????-1.88390559e-014

C3????2.86010656e-017

C4????-3.18575336e-021

C5????1.45886017e-025

C6????-1.08492931e-029

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L813

K?????0.0000

C1????3.40212872e-008

C2????-1.08008877e-012

C3????4.33814531e-017

C4????-7.40125614e-021

C5????5.66856812e-025

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L81 5

K?????0.0000

C1????-3.15395039e-008

C2????4.30010133e-012

C3????3.11663337e-016

C4????-3.64089769e-020

C5????1.06073268e-024

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L816

K?????0.0000

C1????-2.16574623e-008

C2????-6.67182801e-013

C3????4.46519932e-016

C4????-3.71571535e-020

C5????0.00000000e+000

C6????0.00000000e+000

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

The non-sphere of lens L817

K?????0.0000

C1????2.15121397e-008

C2????-1.65301726e-011

C3????-5.03883747e-015

C4????1.03441815e-017

C5????-6.29122773e-021

C6????1.44097714e-024

C7????0.00000000e+000

C8????0.00000000e+000

C9????0.00000000e+000

Claims (82)

1. object lens (611,711), projection objective in particular for little printing apparatus for projection exposure (81), have a plurality of lens (L601-L630, L801-L817), have at least one lens of making by crystal of fluoride (1), it is characterized in that, described at least one lens (1) are (the 100)-lens with lens axis (EA), and it is approximately perpendicular to { the crystal face of 100}-crystal face or the crystal of fluoride equivalent with it.

2. object lens as claimed in claim 1, wherein (100)-lens are the lens deads in line with rotational symmetric lens and this axis of symmetry and (100)-lens of an axis of symmetry.

3. as each described object lens in the claim 1 to 2, has an optical axis (OA), wherein the lens axis of (100)-lens and the optical axis coincidence of object lens.

As claim 1 to 3 to each described object lens, wherein extend to an image surface (O ') and at least one light ray (609 from an object lens face (O) at object lens interior lights ray, 713,715) has a ray angle in (100)-lens inside with respect to the lens axis, it is greater than 25 °, especially greater than 30 °.

5. as each described object lens in the claim 1 to 4, wherein extend to an image surface and all light rays have a ray angle with respect to the lens axis in (100)-lens inside from an object lens face at object lens interior lights ray, it is 45 ° to the maximum, especially is arcsin to the maximum

Wherein NA is called the digital lattice ommatidium of image-side and n _FKRefractive index for crystal of fluoride.

6. as each described object lens in the claim 1 to 5, wherein apertured mask have a diaphragm diameter and wherein (100)-lens have a lens diameter, wherein lens diameter is less than 85% of diaphragm diameter, especially less than 80%.

7. as each described object lens in the claim 1 to 6, have an image surface, wherein (L630 is from the nearest lens of image surface L817) to (100)-lens.

8. object lens (611,711), projection objective in particular for little printing apparatus for projection exposure (81), the lens element that has at least two lens or make by crystal of fluoride, the lens axis of wherein said lens or lens element roughly points to a host crystal direction respectively, wherein occur the beam with ray on the picture point of an image surface, they have an azimuth angle alpha respectively _R, a view angle theta _RWith an optical path difference Δ OPL, it is characterized in that described lens or lens element are provided with the relative rotation around the lens axis, make the optical path difference Δ OPL (α of beam for two mutually orthogonal straight line polarized states _R, θ _R) dispose as azimuth angle alpha _RAnd view angle theta _RFunction have one and compare the numerical value that greatly reduces with lens or lens element, the host crystal direction that its lens orientation of its axis is identical and they are not to be provided with the relative rotation around the lens axis.

9. object lens as claimed in claim 8, wherein said optical path difference Δ OPL is as azimuth angle alpha _RFunction for a given view angle theta _RVariation less than 30%, especially less than 20%.

10. as each described object lens in claim 8 or 9, wherein said lens or lens element have a birefringence configuration Δ n (α respectively _L, θ _L), its birefringence value Δ n depends on an azimuth angle alpha with respect to the reference direction of vertical lens axis _LView angle theta with relative lens axis _R, wherein Δ n (α is disposed in birefringence _L, θ _L) have a k azimuthal symmetry, wherein between the reference direction of each lens or lens element, define rotation angle γ, wherein n lens or n lens element constitute a group, and Δ n (α is disposed in the host crystal direction that portion's lens orientation of its axis is identical within it or host crystal direction equivalent with it and portion's birefringence within it _L, θ _L) the relative datum direction has identical orientation and distribute, wherein be for per two lens in the group or the rotation angle γ between the lens element:

Wherein m is an integer.

11. object lens as claimed in claim 10, the aperture ray of a ragged edge of wherein said beam (609,713,715) has a view angle theta respectively at lens or lens element inside _LAnd view angle theta _LThe maximum of lens in a group or lens element inside is changed to 30%, and especially maximum is changed to 20%.

12. as each described object lens in claim 10 or 11, the aperture ray of a ragged edge of wherein said beam (609,713,715) moves a light path RL respectively at lens or lens element inside _LAnd this light path RL _LThe inner maximum of lens in one group or lens element is changed to 30%, and especially maximum is changed to 20%.

13. as each described object lens in the claim 10 to 12, wherein the optical path difference Δ OPL that each lens in for a group or lens element are determined when rotation angle γ=0 ° is for the aperture ray (609 of a ragged edge of beam, 713,715) maximum is changed to 30%, and especially maximum is changed to 20%.。

14. as each described object lens in the claim 10 to 13, wherein said lens combination comprises 2 to 4 lens or lens elements.

15. object lens as claimed in claim 14, wherein said lens (L629, L630) or lens element be adjacent to be provided with, bonding especially mutually.

16. as each described object lens in the claim 10 to 15, wherein said object lens have at least two groups, they have counterrotating lens or lens element respectively.

17. as each described object lens in the claim 8 to 16, wherein said lens orientation of its axis＜111 〉-the birefringence configuration Δ n (α of crystallographic direction or the host crystal direction equivalent and lens or lens element with it _L, θ _L) have 3 azimuthal symmetry.

18. as each described object lens in the claim 8 to 16, wherein said lens orientation of its axis＜100 〉-the birefringence configuration Δ n (α of crystallographic direction or the host crystal direction equivalent and lens or lens element with it _L, θ _L) have 4 azimuthal symmetry.

19. as each described object lens, wherein lens orientation of its axis＜110 in the claim 8 to 16 〉-the birefringence configuration Δ n (α of crystallographic direction or the host crystal direction equivalent and lens or lens element with it _L, θ _L) have 2 azimuthal symmetry.

20., the lens in one of them first group or lens orientation of its axis＜100 of lens element as each described object lens in the claim 8 to 19 〉-crystallographic direction or the host crystal direction equivalent and one second group lens or lens orientation of its axis＜111 of lens element with it 〉-crystallographic direction or the host crystal direction equivalent with it.

21., the lens in one of them first group or lens orientation of its axis＜100 of lens element as each described object lens in the claim 8 to 19 〉-crystallographic direction or the host crystal direction equivalent and one second group lens or lens orientation of its axis＜110 of lens element with it 〉-crystallographic direction or the host crystal direction equivalent with it.

22. as claim 20 or 21 described object lens, wherein said optical path difference configuration Δ OPL (α _R, θ _R) by the first optical path difference Δ OPL that causes by all first group lens or lens element ₁(α _R, θ _R) configuration and the second optical path difference Δ OPL that causes by all second group lens or lens element ₂(α _R, θ _R) configuration is combined, and the first optical path difference Δ OPL ₁(α _R, θ _R) configuration the maximal value summation and the second optical path difference Δ OPL ₂(α _R, θ _R) configuration maximal value summation difference be 30% to the maximum, especially be 20% to the maximum.

23. as the described object lens of claim 8 to 22 (611), wherein said lens or lens element belong to a plurality of optical elements with optical surface, wherein at least one optical surface is furnished with a compensating coating, the optical path difference Δ OPL (α of described beam _R, θ _R) dispose as azimuth angle alpha _RAnd view angle theta _RFunction compare with the object lens that do not have compensating coating and have the numerical value that greatly reduces.

24. object lens as claimed in claim 23 (611), the optical element that wherein has compensating coating has an element axis, and wherein compensating coating has an effective birefringence configuration, and its effective birefringence value depends on the azimuth angle alpha with respect to the reference direction of perpendicular elements axis _FWith view angle theta with respect to the element axis _F

25. object lens as claimed in claim 24, effective birefringence configuration of wherein said compensating coating is for view angle theta _F=0 o'clock greatly on zero.

26. as each described object lens in claim 24 and 25, wherein effective birefringence is configured in primary side and only depends on view angle theta _F

27. as each described object lens in the claim 23 to 26, the optical element that wherein has compensating coating is lens of being made by crystal of fluoride, wherein said element axis is the lens axis of the lens made by crystal of fluoride.

28. to each described object lens, wherein a plurality of optical elements are furnished with compensating coating as claim 23 to 27.

29. to each described object lens, wherein all optical elements are furnished with compensating coating as claim 23 to 28.

30. to each described object lens, wherein said crystal of fluoride is a calcium-crystal of fluoride as claim 1 to 29, a strontium-crystal of fluoride or a barium-crystal of fluoride.

31. object lens (611), projection objective in particular for little printing apparatus for projection exposure, have a plurality of optical elements, especially lens of making by crystal of fluoride, has optical surface, beam with ray wherein appears on the picture point of an image surface, they have an optical path difference Δ OPL for two mutually orthogonal straight line polarized states respectively, it is characterized in that, at least one optical surface is furnished with a compensating coating (613), wherein said compensating coating disposes like this, the optical path difference Δ OPL of beam is compared with the object lens that do not have coating have the numerical value that greatly reduces.

32. object lens as claimed in claim 31, wherein said optical element with compensating coating has an element axis, and wherein compensating coating has an effective birefringence configuration, and its effective birefringence value depends on the azimuth angle alpha with respect to the reference direction of perpendicular elements axis _FWith view angle theta with respect to the element axis _F

33. object lens as claimed in claim 32, effective birefringence configuration of wherein said compensating coating is for view angle theta _F=0 o'clock greatly on zero.

34. as claim 32 and 33 described object lens, wherein said effective birefringence is configured in primary side and depends on view angle theta _F

35. as each described object lens in the claim 32 to 34, the optical element that wherein has compensating coating is removable.

36. as each described object lens in the claim 31 to 35, wherein at least two optical elements are lens of being made by crystal of fluoride, wherein said lens or lens element have the lens axis, wherein lens or lens element are provided with so rotatably around the lens axis each other, make the optical path difference configuration Δ OPL (α of beam _R, θ _R) as azimuth angle alpha _RAnd view angle theta _RFunction have one and compare the numerical value that greatly reduces with lens or lens element, the host crystal direction that its lens orientation of its axis is identical and they are not to be provided with the relative rotation around the lens axis.

37. object lens as claimed in claim 36, wherein said optical path difference Δ OPL is as azimuth angle alpha _RFunction for a given view angle theta _RVariation less than 30%, especially less than 20%.

38. as claim 36 or 37 described object lens, wherein said lens or lens element have a birefringence configuration Δ n (α respectively _L, θ _L), its birefringence value Δ n depends on an azimuth angle alpha with respect to the reference direction of vertical lens axis _LView angle theta with relative lens axis _R, wherein Δ n (α is disposed in birefringence _L, θ _L) have a k azimuthal symmetry, wherein between the reference direction of each lens or lens element, define rotation angle γ, wherein n lens or n lens element constitute a group, and Δ n (α is disposed in the host crystal direction that portion's lens orientation of its axis is identical within it or host crystal direction equivalent with it and portion's birefringence within it _L, θ _L) being as the criterion with reference direction has identical orientation and distribute, wherein be for per two lens in the group or the rotation angle γ between the lens element:

Wherein m is an integer.

39. as each described object lens in the claim 36 to 38, the wherein said optical element of being furnished with compensating coating is lens of being made by crystal of fluoride, and wherein the element axis is the lens axis of the lens made by crystal of fluoride.

40. as each described object lens in the claim 36 to 39, wherein a plurality of optical elements are furnished with compensating coating.

41. as each described object lens in the claim 1 to 40, wherein said object lens have the digital lattice ommatidium NA of digital lattice ommatidium NA and image-side existence greater than 0.7, especially greater than 0.8 in image-side.

42. as each described object lens in the claim 1 to 41, wherein said object lens are used for wavelength less than 200nm.

43. as each described object lens in the claim 1 to 42, wherein said object lens are used for wavelength less than 160nm.

44. as each described object lens in the claim 1 to 43, wherein said object lens (611) are reflecting objectives.

45. as each described object lens in the claim 1 to 44, wherein said object lens are catadioptric objectives (711), it has lens and at least one mirror (Sp2).

46. as each described object lens in the claim 1 to 45, wherein all lens are made by calcium-fluoride.

47. a little printing apparatus for projection exposure (81) comprises a luminescent system (83), one as each described object lens (85) in the claim 1 to 46, it is imaged on the photosensitive substrate (815) mask that is loaded with structure.

48. method by little printing apparatus for projection exposure processing semiconductor structure member as claimed in claim 47.

49. one kind is used to process object lens, method in particular for the projection objective of processing a little printing apparatus for projection exposure, these object lens have at least two lens or the lens elements made by crystal of fluoride, wherein said lens or lens element have the lens axis, they roughly point to a host crystal direction respectively, it is characterized in that for a beam with ray, they have an azimuth angle alpha respectively in an image surface _R, a view angle theta _RWith an optical path difference Δ OPL, determine optical path difference Δ OPL (α for lens or lens element for two mutually orthogonal straight line polarized states _R, θ _R) configuration, described lens or lens element are provided with the relative rotation around the lens axis, make the optical path difference Δ OPL (α of beam _R, θ _R) configuration has one and compare the numerical value that greatly reduces with lens or lens element, the host crystal direction that its lens orientation of its axis is identical and they are not to be provided with the relative rotation around the lens axis.

50. method as claimed in claim 49, wherein said object lens have first group and one second group with lens and lens element with lens or lens element, the lens in first group or lens orientation of its axis＜100 of lens element 〉-crystallographic direction or the host crystal direction equivalent and second group lens or lens orientation of its axis＜111 of lens element with it 〉-crystallographic direction or the host crystal direction equivalent with it.

51. method as claimed in claim 49, wherein said object lens have first group and one second group with lens and lens element with lens or lens element, the lens in first group or lens orientation of its axis＜100 of lens element 〉-crystallographic direction or the host crystal direction equivalent and second group lens or lens orientation of its axis＜110 of lens element with it 〉-crystallographic direction or the host crystal direction equivalent with it.

52. as each described method in the claim 49 to 51, wherein for a beam with ray, they have an azimuth angle alpha respectively in an image surface _R, a view angle theta _RWith an optical path difference Δ OPL for two mutually orthogonal straight line polarized states, an optical path difference Δ OPL (α _R, θ _R) configuration, wherein by optical path difference Δ OPL (α _R, θ _R) configuration determines that effective birefringence configuration of a compensating coating is used to reduce optical path difference Δ OPL (α _R, θ _R), wherein effective birefringence value of compensating coating depends on one with respect to the azimuth angle alpha perpendicular to the reference direction of the element axis of optical element _FBe the view angle theta of benchmark with the element axis _F, wherein by the structure of the definite compensating coating of birefringence configuration, wherein the optical element of object lens is furnished with compensating coating.

53. one kind is used in object lens, the especially method of compensated birefringence effect in the projection objective of little printing apparatus for projection exposure, wherein said object lens have a plurality of lens that have the optical element of optical surface, especially made by crystal of fluoride, wherein at least one optical element is removable, wherein occur the beam with ray on a picture point of image surface, they have an azimuth angle alpha respectively in an image surface _R, a view angle theta _RWith an optical path difference Δ OPL, wherein determine an optical path difference Δ OPL (α for two mutually orthogonal straight line polarized states _R, θ _R) configuration, wherein by optical path difference Δ OPL (α _R, θ _R) disposing effective birefringence configuration of determining a compensating coating, its effective birefringence value depends on an azimuth angle alpha with respect to the reference direction of the element axis of vertical optical element _FBe the view angle theta of benchmark with the element axis _F, wherein, wherein make removable optical element leave object lens by the structure of the definite compensating coating of effective birefringence configuration, wherein removable optical element is furnished with compensating coating, wherein removable optical element with compensating coating is reinstalled object lens.

54. lens job operation, it is characterized in that, by the crystalline material that on crystal orientation, rotates each other, preferably the plate optics made of crystal of fluoride and especially calcium-fluoride seamlessly splices, especially bonding and with a plurality of then as the bright body of a unanimity be shaped processing and polishing.

55. lens job operation as claimed in claim 54, wherein said plate have a birefringence configuration Δ n (α respectively _L, θ _L), its birefringence value Δ n depends on an azimuth angle alpha with respect to the reference direction of vertical lens axis _LView angle theta with relative lens axis _RAnd this birefringence configuration has k azimuthal symmetry, wherein defines rotation angle γ between the reference direction of each plate, for the rotation angle γ between per two plates is:

Wherein m is an integer.

56. lens job operation as claimed in claim 55, wherein two plates seamlessly splice.

57. as each described lens job operation in claim 55 and 56, wherein said plate has approximately identical thickness.

58., wherein point to＜111 for the first plate face normal as each described lens job operation in the claim 54 to 57 〉-crystallographic direction or host crystal direction equivalent with it and for second plate face normal sensing＜100-crystallographic direction or a host crystal direction equivalent with it.

The summation that second plate has about identical second thickness and first thickness 59. lens job operation as claimed in claim 58, wherein said first plate have about first an identical thickness is 1.5 ± 0.2 with the ratio of the summation of second thickness.

60., wherein point to＜110 for the first plate face normal as each described lens job operation in the claim 54 to 57 〉-crystallographic direction or host crystal direction equivalent with it and for second plate face normal sensing＜100-crystallographic direction or a host crystal direction equivalent with it.

The summation that second plate has about identical second thickness and first thickness 61. lens job operation as claimed in claim 60, wherein said first plate have about first an identical thickness is 4.0 ± 0.4 with the ratio of the summation of second thickness.

62. as each described lens job operation in claim 60 and 61, wherein two first plates and two second plate optics seamlessly splice.

63. as each described lens job operation in claim 60 and 61, wherein four first plates and two second plate optics seamlessly splice.

64. lens is characterized in that processing according to each described method in the claim 54 to 63.

65. object lens, especially a projection objective (611,711) that is used for little printing apparatus for projection exposure (81) is characterized in that, described object lens comprise one as the described lens of claim 64.

66., it is characterized in that described object lens comprise one as the described lens of claim 64 as each described object lens in the claim 1 to 46.

67. object lens, especially as each described object lens in the claim 31 to 36, wherein said compensating coating (510) has a birefringent birefringence configuration that effectively has localized variation.

68. as the described object lens of claim 67, wherein said compensating coating has an effective birefringence configuration, it rotates the element axis that is symmetrical in the element of being furnished with compensating coating substantially.

69. as claim 67 or 68 described object lens, wherein said compensating coating has an effective birefringence configuration, it has a birefringence that increases diametrically or reduce.

70. as each described object lens in claim 67 or 69, wherein said compensating coating has an effective birefringence configuration, it is non-rotational symmetric, especially the orientation modulation that has a birefringence intensity, wherein preferably stipulate a birefringence configuration, it has a plurality of symmetry with respect to the element axis of the optical element of being furnished with compensating coating, especially 2,3,4 or 6 symmetry.

71. as each described object lens in the claim 67 to 70, at least one optical surface of one of them optical element has an anisotropy coating, its preferred design becomes compensating coating.

72. as the described object lens of claim 71, wherein said anisotropy coating has an anisotropic localized variation, wherein this variation comprises the direction of the polarised direction of selecting the superior and/or the absolute value that divides by the phase place that coating produces.

73. one kind is used to process the effective element of auroral polesization, the especially method of a delay element, wherein an effective coating of auroral polesization with given effective birefringence configuration is coated at least one substrate surface of a substrate, by: clad material is coated at least one position of substrate surface or one on the coating that exists on the substrate surface, apply with so big coating angle, make an anisotropic coat structure to occur.

74., wherein carry out following step: make substrate center on a substrate turning axle rotation for the anisotropy of controlling birefringence configuration and/or coating as the described method of claim 73; Clad material by a material source with bigger coating angle to the substrate surface coating; During the substrate rotation, cover clad material in order to produce a coating time relevant with the radial position in coating place according to a given radially time profile in the time mode.

75. as the described method of claim 74, wherein cover like this, make especially＜30 ° to 35 ° little coating angle crested, make material only or at least the overwhelming majority appear on the substrate surface with selected direction with bigger especially 40 ° or bigger coating angle.

76. one kind is used to process the effective element of auroral polesization, the especially method of a delay element, wherein an effective coating of auroral polesization with given effective birefringence configuration is coated at least one substrate surface of a substrate, by: the local birefringence configuration that the back changes coating finished in the coating process.

77., wherein realize described change by completed coating is carried out local loading with an energy that is suitable for changing the coating blastic texture according to a given space distribution as the described method of claim 76.

78. as claim 76 or 77 described methods, wherein said coating is an anisotropic coating.

79. as each described method in the claim 76 to 78, wherein by means of the definite position that loads with energy of one or more masks.

80. as each described method in the claim 76 to 79, the change of the local birefringence of wherein said coating configuration realizes by local heat that limits and/or mechanical influence.

81. by processing auroral polesization effective element, especially delay element as each described method in the claim 73 to 80.

82. one kind is used to process an optical system, especially a method that is used for the projection objective of little printing, has the following step: by using at least one assembling of the element with anisotropy coating or other non-equilibrium coating optical system; Measure optical system and be used to obtain desired effective birefringence configuration of at least one coating, this coating must with described optical system harmonious aspect the auroral polesization; Pull down the optical element of being furnished with coating; The layer characteristic that afterwards changes coating by part qualification ground adding energy is used to produce desired effective birefringence configuration; The optical element that assembling changed.

Images