CN101078813B - Polarizing transforming element, optical lighting device, exposure device and exposure method - Google Patents

Abstract

A polarization conversion element capable of converting, with a limited light quantity loss, a linearly polarized incident light having a polarization direction in an almost single direction into a circumferentially polarized light having a polarization direction in an almost circumferential direction. A polarization conversion element (10) for converting the polarization state of an incident light into a specified polarization state. It is formed of an optical material having optical rotation, for example, quartz, and has a thickness distribution changing in a circumferential direction. The thickness distribution is so set that a linearly polarized light having a polarization direction in an almost single direction is converted into a circumferentially polarized light having a polarization direction in an almost circumferential direction. It has a plurality of circumferentially divided areas (10A-10D), and two arbitrary adjacent areas in the plurality of areas are different in thickness from each other. Also, two arbitrary facing areas in the plurality of areas have optical rotation angles almost equal to each other.

Description

Polarization conversion element, illumination optical apparatus, exposure device and exposure method

The application is original application application number 200580003186.5 (international application no PCT/JP2005/000407), at on 01 14th, 2005 applying date, what denomination of invention was " polarization conversion element, illumination optical apparatus, exposure device and exposure method " divides an application.

Technical field

The invention relates to polarization conversion element, illumination optical apparatus, exposure device and exposure method, and particularly relevant for a kind of exposure device, for making the micro-photographing process of the first-class microcomponent of semiconductor element, image capturing element, liquid crystal display cells, thin film magnetic.

Background technology

About some typical exposure devices, the light beam penetrating from light source is by the compound eye as optical integrator (optical integrator) (fly eye) lens, to form the secondary souce of the material surface light source being consisted of a plurality of light source.The light beam being penetrated by secondary souce (being generally that the illumination pupil of illumination optical apparatus or near the illumination pupil being formed on it distribute), after being limited, is incident in light collecting lens by being configured near the aperture rear side focus face of fly's-eye lens.

Utilize light collecting lens and by the light beam of light harvesting, and be formed the cover curtain of determining to some extent pattern and overlap and throw light on.Light through covering the pattern of curtain, images on wafer by projection optical system.Then,, on wafer, cover curtain pattern is projected exposure (transfer printing).Again, be formed on the pattern of cover curtain, when by high productive set, for this fine pattern, will be correctly transferred on wafer, it is indispensable on wafer, will obtaining homogeneous Illumination Distribution.

For example, at No. 3246615 open source information of Jap.P. of inventor, announcement is in order to realize the lighting condition with verily transfer printing by the fine pattern of any direction, at the rear side focus face of fly's-eye lens, form the secondary souce of wheel belt shape, and setting and to make the light beam through this wheel belt shape secondary souce, is linear polarization state (being designated hereinafter simply as " Zhou Fangxiang polarized condition ") at the polarization direction of Zhou Fangxiang.

But the technology of above-mentioned open source information, utilizes by the formed circular light beam of fly's-eye lens, restriction has the aperture of wheel belt shape opening, to form wheel belt shape secondary souce.This result, for conventional art, can make aperture produce a large amount of light losses, and then make the production capacity of exposure device low, is therefore not suitable for.

Summary of the invention

Because aforesaid problem, the present invention proposes a kind of polarization conversion element, can will there is the incident light of the linear polarization state of the polarization direction that is about single direction, be transformed into the light of the Zhou Fangxiang polarized condition of the polarization direction that is about Zhou Fangxiang, and can prevent light loss.

Again, the object of this invention is to provide illumination optical apparatus, use polarization conversion element, can the incident light of the linear polarization state of the polarization direction that is about single direction will be had, be transformed into the light of the Zhou Fangxiang polarized condition of the polarization direction that is about Zhou Fangxiang, can well prevent light loss, the wheel belt shape illumination pupil that forms Zhou Fangxiang polarized condition distributes.

Again, the invention provides exposure device and exposure method, use illumination optical apparatus can well prevent light loss, the wheel belt shape illumination pupil that forms Zhou Fangxiang polarized condition distributes, with suitable lighting condition, and can be by fine pattern verily and high yield transferability.

In order to solve foregoing problems, the first embodiment of the present invention provides a kind of polarization conversion element, and the polarized condition of conversion incident light becomes fixed polarized condition, utilizes active optical material, to be formed on Zhou Fangxiang, has thickness variation profile.

According to second embodiment of the invention, an illumination optical apparatus is provided, comprise the light source that illumination light is provided, and the light path between this light source and plane of illumination is configured the polarization conversion element of the first embodiment.

In third embodiment of the invention, illumination optical apparatus is provided, for according to the illumination light of being supplied with by light source, throw light in the illumination optical apparatus of plane of illumination,

The illumination pupil face of aforementioned illumination optical apparatus or with the face of this illumination pupil face conjugation in the light intensity distributions that is formed, about the average specific polarizing coefficient of the 1st direction polarisation in its fixed efficient light sources region with RSP _h(Ave) represent, about the average specific polarizing coefficient of the 2nd direction polarisation with RSP _v(Ave) represent, meet

RSP _h(Ave)＞70％，RSP _v(Ave)＞70％。

Again,

RSP _h(Ave)＝Ix(Ave)/(Ix+Iy)Ave；

RSP _v(Ave)＝Iy(Ave)/(Ix+Iy)Ave。

In this, Ix (Ave) is by any the light beam that passes through fixed efficient light sources region and arrive image planes, average in the intensity of the 1st direction polarized component.Iy (Ave) is by any the light beam that passes through fixed efficient light sources region and arrive image planes, average in the intensity of the 2nd direction polarized component.(Ix+Iy) Ave is average by the intensity of whole beam intensities of passing through fixed efficient light sources region.Again, the illumination pupil face of aforementioned illumination optical apparatus, be defined as the face of the optical Fourier transformational relation of corresponding aforementioned plane of illumination, in the situation of aforementioned illumination optical apparatus and projection optical system combination, can define the face in the illumination optical apparatus with the aperture optical conjugate of projection optical system.Again, the face with the illumination pupil face conjugation of aforementioned illumination optical apparatus, is not limited to the face in aforementioned illumination optical apparatus, for example, when aforementioned illumination optical apparatus and projection optical system combination, and the face in also can projection optical system.More also can be the face detecting in the polarimetry device of polarized condition of illumination optical apparatus (or projection aligner).

Fourth embodiment of the invention, provides exposure device, comprises the illumination optical apparatus of the second embodiment or the 3rd embodiment, through this illumination optical apparatus by the pattern exposure on cover curtain on photonasty substrate.

Fifth embodiment of the invention, provides exposure method, uses the illumination optical apparatus of the second embodiment or the 3rd embodiment, by the pattern exposure on cover curtain on photonasty substrate.

Sixth embodiment of the invention, provides a kind of method of manufacturing polarization conversion element, is the polarized condition of incident light to be transformed into the manufacture method of this polarization conversion element of fixed polarized condition, and it comprises: prepare active optical material; And set this optical material in the thickness distribution of Zhou Fangxiang variation.

Polarization conversion element of the present invention, for example, utilize the optical material just like crystal optical activity to be formed, in the Zhou Fangxiang thickness distribution that changes.In this, thickness distribution, for example, is set the light of the linear polarization state of the polarization direction that makes to be about single direction, is transformed into the light of the Zhou Fangxiang polarized condition of the polarization direction that is about Zhou Fangxiang.Its result, in the present invention, can realize and prevent light loss, will have the incident light of the linear polarization state of the polarization direction that is about single direction, is transformed into the polarisation converting means of light of the Zhou Fangxiang polarized condition of the polarization direction that is about Zhou Fangxiang.Particularly, because utilize active optical material to form polarisation converting means, and then there is wavelength plate on relatively, to be easy to the advantage of manufacturing.

In addition, in illumination optical apparatus of the present invention, because use polarisation converting means, can the incident light of linear polarization state of the polarization direction of single direction will be about, be transformed into the light of the Zhou Fangxiang polarized condition of the polarization direction that is about Zhou Fangxiang, can well prevent light loss, and form the wheel belt shape illumination pupil distribution of Zhou Fangxiang polarized condition.Again, exposure device of the present invention and exposure method, use illumination optical apparatus, can well prevent light loss, and the wheel belt shape illumination pupil that forms Zhou Fangxiang polarized condition distributes, in suitable lighting condition, can loyal and high production capacity ground replicated fine pattern, and then element manufacture also has good production capacity.

For above and other object of the present invention, feature and advantage can be become apparent, preferred embodiment cited below particularly, and coordinate appended graphicly, be described in detail below.

Accompanying drawing explanation

Fig. 1 illustrates the exposure device structural representation according to the embodiment of the present invention.

Fig. 2 illustrates relative wheel belt shape secondary souce, the Action Specification of circular cone prismatic mirror system.

Fig. 3 illustrates relative wheel belt shape secondary souce, the Action Specification of flexible lens.

Fig. 4 illustrates the inner structure signal oblique view of the polarisation monitor of Fig. 1.

Fig. 5 illustrates the inner structure schematic diagram of the polarization conversion element of Fig. 1.

Fig. 6 illustrates crystal optical activity key diagram.

Fig. 7 illustrates the effect that utilizes polarization conversion element, is configured to the wheel belt shape secondary souce schematic diagram of Zhou Fangxiang polarized condition.

Fig. 8 illustrates the effect that utilizes polarization conversion element, is configured to the wheel belt shape secondary souce schematic diagram of footpath direction polarized condition.

Fig. 9 illustrates the variation schematic diagram that a plurality of polarization conversion elements can exchange.

The turntable 10T that Figure 10 illustrates as the exchange mechanism of Fig. 9 is loaded multiple polarization conversion element 10a～10e schematic diagram.

Figure 11 A～11E illustrates multiple polarization conversion element 10a～10e and divides other structural representation.

Figure 12 A～12C illustrates an illustration intention of the secondary souce that utilizes the effect of polarization conversion element to be configured to Zhou Fangxiang polarized condition.

Figure 13 illustrates the structural representation of the rotatable polarization conversion element 10f of optical axis AX that is arranged to unroll.

Figure 14 A～14C illustrates the effect that utilizes polarization conversion element 10f, is configured to an illustration intention of the secondary souce of Zhou Fangxiang polarized condition.

Figure 15 A～15C illustrates the polarization conversion element consisting of 8 fan-shaped basic building blocks, an illustration intention of the rotatable secondary souce of optical axis AX that obtains unrolling.

Figure 16 illustrates polarization conversion element, is configured near the pupil of lamp optical system in position, positive anterior locations (near the position light incident side) illustration of circular cone prismatic mirror system 8 is intended to.

Figure 17 illustrates variation example as shown in figure 16, is the explanation schematic diagram of the formula of satisfying condition (1) with (2).

Figure 18 illustrates polarization conversion element, is configured near the pupil of lamp optical system in position, position one illustration is intended near the pupil of imaging optical system 15.

Figure 19 illustrates in order to detect the polarized condition of light of illumination wafer W and the structural representation of the wafer face polarisation monitor 90 of light intensity.

Figure 20 illustrates and uses the 4 polarization conversion element 10f of cutting apart, and carries out 4 and cuts apart the illumination of Zhou Fangxiang polarisation wheel band, to obtain wheel belt shape secondary souce 31 schematic diagram.

Figure 21 illustrates the actual processing procedure obtaining as the semiconductor element of microcomponent.

Figure 22 illustrates the actual processing procedure obtaining as the liquid crystal display cells of microcomponent.

1: light source 4: polarized condition transformation component

4a:1/4 wavelength plate 4b:1/2 wavelength plate

4c: depolariser 5: diffractive optical elements

6: afocal lens 8: circular cone prismatic mirror system

9: flexible lens 10: polarization conversion element

10A～10D: each primary element 10E: middle section

11: micro-fly's-eye lens 12: polarisation monitor

12a: optical splitter 13: light collection system

14: cover curtain shield 15: imaging optical system

104c: polarisation is cleared up the material M of portion: cover curtain

PL: projection optical system W: wafer

Embodiment

Fig. 1 illustrates the exposure device schematic diagram according to the embodiment of the present invention.In Fig. 1, the normal direction that to set respectively along photonasty substrate be wafer W is Z axis, and in the face of wafer W, the direction parallel with the paper of Fig. 1 is Y-axis, and the interior direction vertical with the paper of Fig. 1 of face of wafer W is X-axis.Please refer to Fig. 1, the exposure device of the present embodiment, comprises in order to supply with the light source 1 of the light (illumination light) of exposure.

As light source 1, for example, can use the KrF quasi-molecule laser source of supplying with 248nm wavelength light or the ArF quasi-molecule laser source of supplying with 193nm wavelength light.The approximately parallel beam penetrating from light source 1 along Z direction, has the rectangular-shaped section of elongated extension, and is incident in the optical beam expander 2 (expander) consisting of a pair of lens 2a and 2b along directions X.Each other lens 2a and 2b, in the paper of Fig. 1, (in YZ plane) has respectively negative refracting power and positive refracting power.Therefore, be incident in the light beam of optical beam expander 2, in the paper of Fig. 1, be exaggerated, and be shaped as the light beam of fixed to some extent rectangular cross section.

About parallel light beam through the optical beam expander 2 as shaping optical system, it is tended to after Y-direction by catoptron 3 warpages, through 1/4 wavelength plate 4a, 1/2 wavelength plate 4b, depolariser (depolarizer) 4c and wheel, be with illuminating diffractive optical elements 5, and be incident in without focus (afocal) lens 6.In this, 1/4 wavelength plate 4a, 1/2 wavelength plate 4b and depolariser 4c, as described later, form polarized condition transformation component 4.Without focus optical system, be set as: make afocal lens 6, its focal position, front side is approximately consistent with the position of diffractive optical elements 5, and rear side focal position is approximately consistent with the position of determining as shown in phantom in FIG. face 7.

Generally, diffractive optical elements, substrate is formed with difference in height, and it is spaced apart light (illumination light) the wavelength degree of exposure, makes incident beam have diffraction in desired angle.Particularly, wheel is with illuminating diffractive optical elements 5, when to have section be rectangular-shaped parallel beam incident, has in far field the function that (far-field) (or Fraunhofer diffraction region) forms wheel belt shape light intensity distributions.

Therefore, be incident in the approximately parallel beam as the diffractive optical elements 5 of light beam conversion element, form after the light intensity distributions of wheel belt shape at the pupil face of afocal lens 6, about parallel beam is penetrated from afocal lens 6.Near pupil face in light path between the front lens group 6a of afocal lens 6 and rear lens group 6b or its, be configured circular cone prismatic mirror (axicon) system 8, after its detailed structure and effect are described in again.Below, be simple declaration, ignore circular cone prismatic mirror system 8, basic structure and effect are described.

Light beam through afocal lens 6, through the flexible lens 9 (zoom lens) and polarization conversion element 10 of variable σ value use, and be incident in the micro-fly's-eye lens (or fly's-eye lens) 11 as optical integrator (optical integrator).The structure of polarization conversion element 10 and Action Specification are in rear.Micro-fly's-eye lens 11 is by length and breadth and the optical element that forms of a plurality of micro lens with positive refracting power of intensive assortment.Generally speaking, micro-fly's-eye lens is for example that to utilize planopaallel plate to apply etch processes made to form micro lens group.

Then, form each micro lens of micro-fly's-eye lens, more small than each lens unit (lens element) that forms fly's-eye lens.Again, micro-fly's-eye lens, the fly's-eye lens forming from lens unit by mutually isolated is different, and a plurality of micro lens (small flexion face) are mutually not isolated and integrally formed.Yet in the viewpoint being configured in length and breadth at the lens unit with positive refracting power, micro-fly's-eye lens is the optical integrator of the corrugated Splittable identical with fly's-eye lens.

Determine face 7 position be configured in flexible lens 9 focal position, front side near, and the plane of incidence of micro-fly's-eye lens 11 be configured in flexible lens 9 rear side focal position near.In other words, the plane of incidence that flexible lens 9 are configured to determine face 7 and micro-fly's-eye lens 11 is essentially fourier transform relation, and then is configured to the pupil face of afocal lens 6 and the plane of incidence of micro-fly's-eye lens 11 for optical conjugate roughly.

Then, on the plane of incidence of micro-fly's-eye lens 11, identical with the pupil face of afocal lens 6, be for example formed the wheel belt shape range of exposures as center with optical axis AX.All shapes of this wheel belt shape range of exposures are that the focal length with the lens 9 that stretch is interdependent and similarly change.Each micro lens that forms micro-fly's-eye lens 11 has rectangular-shaped section, and it is similar to the shape shape of exposure area (and then will form on wafer W) that will form range of exposures on cover curtain M.

The light beam of the micro-fly's-eye lens 11 of incident is utilize a plurality of micro lens and cut apart by two dimension, its rear side focus face or its neighbouring (and then illumination pupil), by incident beam, having the secondary souce with the about same light intensity distributions of the range of exposures being formed, is that the secondary souce being formed as the material surface light source of the wheel belt shape at center with optical axis AX is formed.From the rear side focus face of micro-fly's-eye lens 11 or near the light beam of the secondary souce being formed it, after optical splitter 12a (beam splitter) and light collection system 13, with cover curtain shield (mask blind) overlapping ground illumination.

Then, the cover curtain shield 14 as illumination visual field aperture, has formed rectangular-shaped range of exposures, its corresponding shape and focal length that forms each micro lens of micro-fly's-eye lens 11.Moreover inside is provided with the polarisation monitor 12 of optical splitter 12a, its inner structure and effect are as described later.Through the light beam that covers the rectangular-shaped peristome (transmittance section) of curtain shield 14, after the light harvesting effect that is subject to imaging optical system 15, be radiated at formation to overlapping and determine to some extent on the cover curtain M of pattern.

That is, imaging optical system 15, is formed on cover curtain M the picture of the rectangular-shaped peristome of cover curtain shield 14.Through the light beam that covers the pattern of curtain M, again through projection optical system PL, it is on wafer W that the picture of cover curtain pattern is formed to photonasty substrate.Then, in the vertical plane of the optical axis AX with projection optical system PL (XY face), utilize and drive two-dimensionally control wafer W to carry out all or scan exposure, the pattern of cover curtain M is sequentially exposed to each exposure area of wafer W.

Again, in polarized condition switching part 4,1/4 wavelength plate 4a is configured and can rotates freely on the crystal optics axle as center with optical axis AX, by the elliptical polarized light optical beam transformation of the incident light beam of polarized light that is in line.Again, 1/2 wavelength plate 4b is configured and can rotates freely on the crystal optics axle as center with optical axis AX, and the plane of polarisation of the linear polarization of incident is changed.Again, depolariser 4c utilizes and to have the wedge shape crystal prism of complementary shape and wedge shape quartz prism and be configured.Crystal prism and quartz prism, as the prism assembly of one, are configured illumination path can freely be inserted and be taken off.

Use under KrF quasi-molecule laser source or the situation of ArF quasi-molecule laser source as light source 1, the light being penetrated from these light sources, generally has more than 95% degree of polarization, and the light of about linear polarization is incident in 1/4 wavelength plate 4a.But, in light path between light source 1 and polarized condition switching part 4, while having the situation as the right-angle prism of back reflector, the plane of polarisation of the linear polarization of incident is not consistent with P plane of polarisation or S plane of polarisation, utilizes the total reflection of right-angle prism to make linear polarization become elliptical polarized light.

Polarized condition switching part 4, although be for example the elliptical polarized light light beam incident that the total reflection due to right-angle prism causes, utilizes the effect of 1/4 wavelength plate 4a to be transformed into linear polarization light beam, is incident in 1/2 wavelength plate 4b.The crystal optics axle of 1/2 wavelength plate 4b, when the plane of polarisation of the polarisation that is in line of corresponding incident is set 0 degree or 90 for and spent, is incident in the light beam of the linear polarization of 1/2 wavelength plate 4b, and its plane of polarisation can not change and pass through.

Again, the crystal optics axle of 1/2 wavelength plate 4b, the plane of polarisation of the linear polarization of corresponding incident, with the situation of 45 degree settings, is incident in the plane of polarisation of the linear polarization light beam of 1/2 wavelength plate 4b, only with 90 degree, changes the light that is transformed into linear polarization.Moreover, the crystal optics axle of the crystal prism of depolariser 4c, the plane of polarisation of the linear polarization of corresponding incident is configured to the situation of 45 degree, and the light of the linear polarization of incident crystal prism is transformed into the light of non-polarized condition (non-polarization light).

In polarized condition switching part 4, when depolariser, 4c locates in illumination path, and making the plane of polarisation of linear polarization of the relative incident of crystal optics axle of crystal prism is 45 degree.In addition, the plane of polarisation of the linear polarization of the relative incident of crystal optics axle of crystal prism, while being set as the angle of 0 degree or 90 degree, the plane of polarisation of the linear polarization of incident crystal prism can not change and pass through.Again, the plane of polarisation of the linear polarization of the relative incident of crystal optics axle of 1/2 wavelength plate 4b, while being set as the angle of 22.5 degree, the light of the linear polarization of incident 1/2 wavelength plate 4b, is transformed into and contains that plane of polarisation can not change and the light of non-polarized condition by linear polarization composition and the plane of polarisation linear polarization composition that only 90 degree change.

For polarized condition switching part 4, as above-mentioned, the light of linear polarization is incident in 1/2 wavelength plate 4b, is for following simple declaration, the light in the Z of Fig. 1 direction with the linear polarization (hereinafter referred to as Z direction polarisation) of polarization direction (direction of an electric field), it is incident in 1/2 wavelength plate 4b.When depolariser 4c locates in illumination path, the plane of polarisation (polarization direction) that is incident in the relative Z direction of the crystal optics axle polarisation of 1/2 wavelength plate 4b is set as 0 degree or 90 degree, and be incident in the Z direction polarisation of 1/2 wavelength plate 4b, the Z direction polarisation that its plane of polarisation can not change passes through, and is incident in the crystal prism of depolariser 4c.The crystal optics axle of crystal prism, the plane of polarisation of the Z direction polarisation of relative incident, because be set as the angle of 45 degree, the light of incident crystal prism Z direction polarisation is transformed into the light of non-polarized condition.

Pass crystal prism by the light of non-polarization light, through the quartz prism of (compensa tor) as compensation is incident in diffractive optical elements 5 with non-polarized condition for compensating light direct of travel.On the one hand, the plane of polarisation that is incident in the relative Z direction of the crystal optics axle polarisation of 1/2 wavelength plate 4b is set as 45 while spending, be incident in the light of the Z direction polarisation of 1/2 wavelength plate 4b, its plane of polarisation only 90 degree changes, as the directions X at Fig. 1 has the light of the linear polarization (hereinafter referred to as directions X polarisation) of polarization direction (direction of an electric field), be incident in the crystal prism of depolariser 4c.Relatively be incident in the plane of polarisation of directions X polarisation of the crystal optics axle of crystal prism, because be set as 45 degree, the light of the directions X polarisation of incident crystal prism, is transformed into non-polarized condition, and through quartz prism, and be incident in diffractive optical elements 5 with non-polarized condition.

Otherwise, when depolariser 4c backs out from illumination path, when the crystal optics axle that is incident in 1/2 wavelength plate 4b is set as 0 degree or 90 and spends with respect to the plane of polarisation of Z direction polarisation, the light that is incident in the Z direction polarisation of 1/2 wavelength plate 4b can not change and pass through, and with Z direction polarized condition, is incident in diffractive optical elements 5.On the other hand, the crystal optics axle that is incident in 1/2 wavelength plate 4b is set as 45 while spending with respect to the plane of polarisation of Z direction polarisation, be incident in the light of the Z direction polarisation of 1/2 wavelength plate 4b, plane of polarisation can only change 90 degree and become the light of directions X polarisation, and is incident in diffractive optical elements 5 with directions X polarized condition.

As above-mentioned, for polarized condition switching part 4, utilize and determine that depolariser 4c inserts the location of illumination path, can make the light of non-polarized condition be incident in diffractive optical elements 5.Again, depolariser 4c is backed out from illumination path, and utilize to set the crystal optics axle that makes 1/2 wavelength plate 4b be 0 degree or 90 degree with respect to the plane of polarisation of the Z direction polarisation of incident, can make the light of Z direction polarized condition be incident in diffractive optical elements 5.Moreover depolariser 4c backs out from illumination path, and utilize to set the crystal optics axle that makes 1/2 wavelength plate 4b be 45 degree with respect to the plane of polarisation of the Z direction polarisation of incident, can make the light of directions X polarized condition be incident in diffractive optical elements 5.

In other words, for polarized condition switching part 4, the effect of the polarized condition switching part that utilization is comprised of 1/4 wavelength plate 4a, 1/2 wavelength plate 4b and depolariser 4c, the polarized condition (and then polarized condition of the light of illuminating cover curtain M and wafer W) of the incident light of past diffractive optical elements 5, can between linear polarization state and non-polarized condition, switch, in the situation of linear polarization state, can switch in (between Z direction polarized condition and directions X polarized condition) between orthogonal polarized condition.

Moreover, for polarized condition switching part 4,1/2 wavelength plate 4b is backed out from illumination path together with depolariser 4c, and utilize the crystal optics axle of 1/4 wavelength plate 4a to set desired angle with respect to the elliptical polarized light of incident, the light of rotatory polarization can be incident in diffractive optical elements 5.Upper as another, utilize the effect of 1/2 wavelength plate 4b, the polarized condition of the incident light of past diffractive optical elements 5, can set for and have in any direction the linear polarization of polarization direction state.

Take second place, circular cone prismatic mirror system 8, along light source side, by subtend light source side, be that plane and subtend cover curtain side are the 1st 8a of prism portion of recessed cone shape flexion face, with subtend cover curtain side be that the 2nd 8b of prism portion that plane and subtend light source side are protruding cone shape flexion face is formed.The dome taper flexion face of the recessed coniform flexion face of the 1st 8a of prism portion and the 2nd 8b of prism portion is can engage and complementary shape.Again, at least one of the 1st 8a of prism portion and the 2nd 8b of prism portion is configured and can moves along optical axis AX.Interval between the dome taper flexion face of the recessed coniform flexion face of the 1st 8a of prism portion and the 2nd 8b of prism portion is variable.

In this, for the recessed coniform flexion face of the 1st 8a of prism portion and the dome taper flexion face of the 2nd 8b of prism portion, be the state being bonded with each other, circular cone prismatic mirror system 8 is as the function of planopaallel plate, and can not have influence on the wheel belt shape secondary souce being formed.Yet, make between the recessed coniform flexion face of the 1st 8a of prism portion and the dome taper flexion face of the 2nd 8b of prism portion from time, circular cone prismatic mirror system 8 is as the function of so-called optical beam expander.Therefore,, along with the interval variation of circular cone prismatic mirror system 8, change the incident angle of light to determined face 7.

Fig. 2, illustrates relative wheel belt shape secondary souce, the Action Specification of circular cone prismatic mirror system.With reference to Fig. 2, at the state (hereinafter referred to as standard state) of setting the focal length minimum value that is spaced apart zero and flexible lens 9 of circular cone prismatic mirror system 8, be formed minimum wheel belt shape secondary souce 30a, utilization makes the interval of circular cone prismatic mirror system 8 expand to institute's definite value from zero, its width (1/2 of the difference of external diameter and internal diameter: represent with arrow in figure) can not change, external diameter expands together with internal diameter, and is varied to wheel belt shape secondary souce 30b.In other words, utilize the effect of circular cone prismatic mirror system 8, the width of wheel belt shape secondary souce can not change, and it is taken turns band and changes than (inner/outer diameter) and size (external diameter).

Fig. 3 illustrates relative wheel belt shape secondary souce, the Action Specification of flexible lens.With reference to Fig. 3, the wheel belt shape secondary souce 30a being formed in standard state, utilizes the focal length of flexible lens 9 to expand to institute's definite value from minimum value, and its all shape similarly expands and is varied to wheel belt shape secondary souce 30c.In other words, utilize the effect of flexible lens 9, the wheel band of wheel belt shape secondary souce can not change than, and its width changes with size (external diameter).

Fig. 4 illustrates the inner structure signal oblique view of the polarisation monitor of Fig. 1.With reference to Fig. 4, polarisation monitor 12 comprises: the 1st optical splitter 12a that is configured in the light path between micro-fly's-eye lens 11 and light collection system 13.The 1st optical splitter 12a is for example the kenel of utilizing the parallel panel (being plain glass) that there is no coating that quartz glass forms, and it has the function from light path taking-up by the reflected light of the different polarized condition of the polarized condition with incident light.

The light that utilizes the 1st optical splitter 12a and be removed from light path, is incident in the 2nd optical splitter 12b.The 2nd optical splitter 12b is identical with the 1st optical splitter 12a, for example, be the parallel panel kenel that there is no coating of utilizing quartz glass to form, and it has the function of the reflected light generation that makes the polarized condition different with the polarized condition of incident light.Then, set the S polarisation that makes the P polarisation of relative the 1st optical splitter 12a become relative the 2nd optical splitter 12b, and the S polarisation of relative the 1st optical splitter 12a becomes the P polarisation of relative the 2nd optical splitter 12b.

Again, see through only the utilizing the 1st photometric detector 12c of the 2nd optical splitter 12b and be detected, what at the 2nd optical splitter 12b, be reflected only utilizes the 2nd photometric detector 12d and is detected.The output of the 1st photometric detector 12c and the 2nd photometric detector 12d, is defeated by respectively control part (not being shown in figure).Control part drives 1/4 wavelength plate 4a, 1/2 wavelength plate 4b and the depolariser 4c that forms polarized condition switching part 4 according to need.

As above-mentioned, about the 1st optical splitter 12a and the 2nd optical splitter 12b, for the reflectivity of P polarisation and the reflectivity of S polarisation, be in fact different.Therefore, for polarisation monitor 12, reflected light from the 1st optical splitter 12a, for example contain approximately 10% the S polarized component (being the P polarized component to the 2nd optical splitter 12b to the S polarized component of the 1st optical splitter 12a) toward the incident light of the 1st optical splitter 12a, and for example toward approximately 1% P polarized component (being the S polarized component to the 2nd optical splitter 12b to the P polarized component of the 1st optical splitter 12a) of the incident light of the 1st optical splitter 12a.

Again, reflected light from the 2nd optical splitter 12b, for example contain toward the P polarized component (being the S polarized component to the 2nd optical splitter 12b to the P polarized component of the 1st optical splitter 12a) of the approximately 10% * 1%=0.1% of the incident light of the 1st optical splitter 12a, with for example toward the approximately 1% * 10%=0.1% of the incident light of the 1st optical splitter 12a S polarized component (being the P polarized component to the 2nd optical splitter 12b to the S polarized component of the 1st optical splitter 12a).

So, for polarisation monitor 12, the 1 optical splitter 12a, respond its reflection characteristic and there is the function that the reflected light with the different polarized condition of incident light polarized condition is taken out from light path.Its result, seldom be subject to the impact of the polarisation change that the 2nd optical splitter 12b causes, according to the output of the 1st photometric detector 12c (about the light intensity data that sees through of the 2nd optical splitter 12b, be the light intensity data from the approximately identical polarized condition of reflected light of the 1st optical splitter 12a), can detect toward the polarized condition (degree of polarization) of the incident light of the 1st optical splitter 12a, and then toward the polarized condition of covering the illumination light of curtain M.

Again, for polarisation monitor 12, the P polarisation that is set to relative the 1st optical splitter 12a is the S polarisation to the 2nd optical splitter 12b, and is the P polarisation to the 2nd optical splitter 12b to the S polarisation of the 1st optical splitter 12a.Its result, according to the output of the 2nd photometric detector 12d (about the 1st optical splitter 12a and the 2nd optical splitter 12b by catoptrical intensity data in turn), be not subject in fact toward the impact of the variation of the polarized condition of the incident light of the 1st optical splitter 12a, can detect toward the light quantity (intensity) of the incident light of the 1st optical splitter 12a, and then toward the light quantity of covering the illumination light of curtain M.

Then, use polarisation monitor 12, detect toward the polarized condition of the incident light of the 1st optical splitter 12a, and then can determine whether that toward the illumination light of cover curtain M be desired non-polarized condition, linear polarization state or rotatory polarization state.Control part is according to the result that detects by polarisation monitor 12, confirm whether toward the illumination light of cover curtain M (and then wafer W) be the situation of desired non-polarized condition, linear polarization state or rotatory polarization state, driving and adjust 1/4 wavelength plate 4a, 1/2 wavelength plate 4b and the depolariser 4c that forms polarized condition switching part 4, is desired non-polarized condition, linear polarization state or rotatory polarization state and can adjust toward the state that covers the illumination light of curtain M.

Moreover, replace wheel with 4 extremely illuminating diffractive optical elements (not being shown in figure) of illuminating diffractive optical elements 5, by being set in illumination path, can carry out 4 utmost point illuminations.4 extremely illuminating diffractive optical elements, have the situation of the parallel beam of rectangular-shaped section in incident, have the function that forms the light intensity distributions of 4 utmost point shapes in its far field.Therefore,, through the light beam of 4 extremely illuminating diffractive optical elements, at the plane of incidence of micro-fly's-eye lens 11, for example form 4 utmost point shape irradiation areas that formed as 4 toroidal irradiation areas at center with optical axis AX.Its result, near the rear side focus face of micro-fly's-eye lens 11 or its, identical with the irradiation area that is formed on the plane of incidence, be formed the secondary souce of 4 utmost point shapes.

Again, replace the diffractive optical elements (not being shown in figure) that wheel is used with the circular illumination of illuminating diffractive optical elements 5, by being set in illumination path, can carry out general circular illumination.The diffractive optical elements that circular illumination is used, has the situation of the parallel beam of rectangular-shaped section in incident, have the function that forms the light intensity distributions of toroidal in its far field.Therefore, the light beam of the diffractive optical elements of using through circular illumination, at the plane of incidence of micro-fly's-eye lens 11, for example forms 4 utmost point shape irradiation areas that formed as the toroidal irradiation area at center with optical axis AX.Its result, near the rear side focus face of micro-fly's-eye lens 11 or its, identical with the irradiation area that is formed on the plane of incidence, be formed the secondary souce of toroidal.

Moreover, replace wheel with other multipole illuminating diffractive optical elements (not being shown in figure) of illuminating diffractive optical elements 5, by being set in illumination path, can carry out various multipole illuminations (2 utmost point illuminations, 8 utmost point illuminations etc.).Similarly, replace wheel with the diffractive optical elements that has appropriate characteristics of illuminating diffractive optical elements 5, by being set in illumination path, can carry out the conversion illumination of various forms.

Fig. 5 illustrates the inner structure schematic diagram of the polarization conversion element of Fig. 1.Fig. 6 illustrates crystal optical activity key diagram.Fig. 7 illustrates the effect that utilizes polarization conversion element, is configured to the wheel belt shape secondary souce schematic diagram of Zhou Fangxiang polarized condition.According to the polarization conversion element 10 of the embodiment of the present invention, be configured in micro-fly's-eye lens 11 just before, be near the pupil of illumination optics device (1～PL) or its.Therefore,, in the situation of wheel band illumination, to polarization conversion element, 10 incidents have the about wheel belt shape of section and the light beam as center with optical axis AX.

With reference to Fig. 5, polarization conversion element 10, has all optical axis AX as the effective coverage of centre wheel band shape, the effective coverage of its wheel belt shape with optical axis AX as center, utilize circumferencial direction be divided into 8 fan shape primary element be configured.At these 8 primary elements, clip a pair of primary element phase mutual identical characteristics that optical axis AX is relative.That is, 8 primary elements, are prolonging light and are respectively containing 2 through 4 kinds of mutual different primary element 10A～10D of the thickness (length of optical axis direction) of direction (Y-direction).

Particularly, the thickness of setting the 1st primary element 10A for is maximum, and the thickness of the 4th primary element 10D is minimum, and the thickness of the Thickness Ratio of the 2nd primary element 10B the 3rd primary element 10C is large.Its result, a side's of polarization conversion element 10 face (for example plane of incidence) is plane, and another side (for example exit facet) utilizes the thickness of each primary element 10A～10D different, becomes concavo-convex.Together with can two-sided (plane of incidence and exit facet) of polarization conversion element 10, form concavo-convex again.

Again, the present embodiment, each primary element 10A～10D is to utilize active optical material that is is that crystal as crystalline material forms, and the crystal optics axle of each primary element 10A～10D is approximately consistent with optical axis AX, be set for approximately consistent with the direct of travel of incident light.Below, with reference to Fig. 6, for the optical activity of crystal, be briefly described.With reference to Fig. 6, the parallel panel optics portion material 100 that the crystal that is d by thickness forms, its crystal optics axle is configured to consistent with optical axis AX.Like this situation, utilizes the optical activity of optics portion material 100, and the polarization direction of the linear polarization of incident only rotates angle θ state to optical axis AX is penetrated.

Now, the optical activity of optics portion material 100 causes the rotation angle of polarization direction (optically-active angle) θ, utilizes thickness d and the optically-active energy ρ of optics portion material 100, with following formula (a), represents.

θ＝d.ρ(a)

Generally, the optically-active energy ρ of crystal, for wavelength interdependence (its different optically-actives of interdependent use light wavelength can be worth: optically-active disperses), particularly, is used light wavelength short, has larger tendency.According to the record of the 167th page at < < applied optics II > >, with respect to the light with the wavelength of 250.3nm, the optically-active energy ρ of crystal is 153.9 degree/mm.

At the present embodiment, the 1st primary element 10A, is configured to thickness d A, and in the situation of the light incident of the linear polarization of Z direction polarisation, Z direction, around the direction of make+180 degree rotations of Y-axis, is to have the light of the linear polarization of polarization direction to make to penetrate in Z direction.Therefore, in this situation, among wheel belt shape secondary souce 31 as shown in Figure 7, be subject to the light beam of the optically-active effect of a pair of the 1st primary element 10A, the polarization direction of the light beam by a pair of circular-arc region 31A that forms is in Z direction.

The 2nd primary element 10B, is configured to thickness d B, and when the light incident of the linear polarization of Z direction polarisation, Z direction, around the direction of make+135 degree rotations of Y-axis, is in Z direction, around Y-axis, to make the direction of-45 degree rotations, has the light of the linear polarization of polarization direction to penetrate.Therefore, in this situation, among wheel belt shape secondary souce 31 as shown in Figure 7, be subject to the light beam of the optically-active effect of a pair of the 2nd primary element 10B, the polarization direction of the light beam by a pair of circular-arc region 31B that forms is that Z direction makes the directions of rotation-45 degree around Y-axis.

The 3rd primary element 10C, is configured to thickness d C, and when the light incident of the linear polarization of Z direction polarisation, Z direction, around the direction of make+90 degree rotations of Y-axis, is to have the light of the linear polarization of directions X polarization direction to penetrate.Therefore, in this situation, among wheel belt shape secondary souce 31 as shown in Figure 7, be subject to the light beam of the optically-active effect of a pair of the 3rd primary element 10C, the polarization direction of the light beam by a pair of circular-arc region 31C that forms is at directions X.

The 4th primary element 10D, is configured to thickness d D, and when the light incident of the linear polarization of Z direction polarisation, Z direction has the light of the linear polarization of polarization direction to penetrate around the directions of make+45 degree rotations of Y-axis.Therefore, in this situation, among wheel belt shape secondary souce 31 as shown in Figure 7, be subject to the light beam of the optically-active effect of a pair of the 4th primary element 10D, the polarization direction of the light beam by a pair of circular-arc region 31D that forms is that Z direction makes the directions of rotation+45 degree around Y-axis.

Moreover, be formed respectively 8 primary elements are combined and can obtain polarization conversion element 10, also can utilize the quartz wafer of planopaallel plate is formed to desired concaveconvex shape (section is poor) and obtains polarization conversion element 10.When polarization conversion element 10 is not backed out from light path, can carry out common circular illumination again,, and set the middle section 10E of toroidal, the footpath direction size that its size is the effective coverage of polarization conversion element 10 be more than or equal to 3/10, be preferably and be more than or equal to 1/3, and there is no optical activity.In this, middle section 10E, can utilize and not have active optical material for example quartzy and form, and can be also simple toroidal opening.But middle section 10E is not the necessary element of polarization conversion element 10.Moreover the size of middle section 10E is that the border by Yu Feici region, Zhou Fangxiang polarized condition region is determined.

In the present embodiment, in Zhou Fangxiang polarisation when illumination wheel band (light beam of the secondary souce by wheel belt shape is configured to the deformation illumination of Zhou Fangxiang polarized condition), there is the light of the linear polarization of Z direction polarisation to be incident in polarization conversion element 10.Its result, near the rear side focus face of micro-fly's-eye lens 11 or its, as shown in Figure 7, the secondary souce of wheel belt shape (pupil of wheel belt shape distributes) 31 is formed, and the light beam of the secondary souce 31 by this wheel belt shape is configured to Zhou Fangxiang polarized condition.For Zhou Fangxiang polarized condition, respectively by forming the light beam of circular-arc region 31A～31D of the secondary souce 31 of wheel belt shape, along the circumferencial direction of each circular-arc region 31A～31D, and be approximately with consistent as the tangential direction of the circle at center with optical axis AX at the polarization direction of the linear polarization state of center.

Then, in the present embodiment, different from the conventional art that light loss occurs greatly because of aperture, utilize the optically-active effect of polarization conversion element 10, can tangible light loss not occur, can form the secondary souce 31 of the wheel belt shape of Zhou Fangxiang polarized condition.In other words, for the illumination optics device of the present embodiment, suppress well light loss, can form the illumination profile of the wheel belt shape of Zhou Fangxiang polarized condition.Moreover for the present embodiment, because use the polarisation effect of optical element, polarization conversion element easy to manufacture, can very slow setting for the thickness deviation of typical each primary element, reaches excellent results.

Again, the Zhou Fangxiang polarisation wheel belt shape illumination distributing according to the wheel belt shape illumination pupil of Zhou Fangxiang polarized condition, only take as the final wafer W of illuminated is irradiated the polarized condition that S polarisation is Main Ingredients and Appearance.In this, S polarisation, is the linear polarization (direction of vertical incidence face is the polarisation of vector vibrations electrically) that has the polarization direction of relative plane of incidence vertical direction.But the plane of incidence, is defined as the interface (plane of illumination: wafer W surface), be included in interface normal on its aspect and the face of incident light that arrives medium when light.

Its result, for the illumination of Zhou Fangxiang polarisation wheel belt shape, can promote the optical property (depth of focus etc.) of projection optical system, can obtain the cover curtain pattern image in the upper high contrast of wafer (photonasty substrate).That is, for the embodiment of the present invention, because use, can suppress well light loss, and to form the illumination optics device that the wheel belt shape illumination pupil of Zhou Fangxiang polarized condition distributes, with suitable lighting condition can be loyal and high production capacity by fine pattern transcription.

Then, in the present embodiment, utilization has the light of the linear polarization of directions X polarization direction to make its incident polarization conversion element 10, light beam by wheel belt shape secondary souce 32 is set as footpath direction polarized condition as shown in Figure 8, and carries out footpath direction polarisation wheel band illumination (being configured to the deformation illumination of footpath direction polarized condition by the light beam of wheel belt shape secondary souce 32).In footpath direction polarized condition, respectively by forming the light beam of the circular-arc region 32A～32D of wheel belt shape secondary souce 32, along the circumferencial direction of each circular-arc region 32A～32D, and linear polarization state in center is approximately with consistent as the radius of a circle mode at center with optical axis AX.

The footpath direction polarisation wheel band illumination distributing according to the wheel belt shape illumination pupil of footpath direction polarized condition, is irradiated to the light as the final wafer W of illuminated, is to take the polarized condition that P polarisation is Main Ingredients and Appearance.In this, P polarisation, is the linear polarization (parallel plane of incidence direction is the polarisations of vector vibrations electrically) of polarization direction of the parallel direction of the plane of incidence relatively defined above.Its result, the illumination of footpath direction polarisation wheel belt shape, the light reflectivity of applied photoresistance on wafer reduces, upper at wafer (photonasty substrate), can obtain good cover curtain pattern image.

Again, in above-described embodiment, the light beam of incident polarization conversion element 10, utilizes in Z direction and has the linear polarization state of polarization direction and the switching having at directions X between the linear polarization state of polarization direction, and realize the illumination of Zhou Fangxiang polarisation wheel band, throws light on footpath direction polarisation wheel band.But, be not limited to this, for example, for there is the incident beam of the linear polarization state of polarization direction at Z direction or directions X, utilize polarization conversion element 10 at the 1st state as shown in Figure 5 and around optical axis AX, make only between rotating the 2nd state of 90 degree, to switch, can realize the illumination of Zhou Fangxiang polarisation wheel band and the illumination of footpath direction polarisation wheel band.

Again, in above-described embodiment, the dead ahead of micro-fly's-eye lens 11 configuration polarization conversion element 10.But, be not limited to this, near the pupil of general illumination device (1～PL) or its, for example, near the pupil of projection optical system PL or its, near the pupil of imaging optical system 15 or its, the dead ahead of circular cone prismatic mirror system 8 (pupil of afocal lens 6 or its near) etc. can configure polarization conversion element 10.

Therefore,, if configure polarization conversion element 10 in projection optical system PL with imaging optical system 15, because the desired effective diameter of polarization conversion element 10 is easily large, considering has any problem obtains the present situation of high-quality large quartz wafer and not good.Again, if the dead ahead of circular cone prismatic mirror system 8 configuration polarization conversion element 10, can make the desired effective diameter of polarization conversion element 10 reduce, but to the distance of the wafer W of final plane of illumination, prevent factor that the coating of reflection from lens and the reflectance coating of mirror etc. can change polarized condition easily intervention in its light path and not good.That is, the reflectance coating that prevents reflection coating and mirror of lens, the easy variation due to the reflectivity of polarized condition (P polarisation and S polarisation) and incident angle, and then easily change polarized condition.

Again, in above-described embodiment, (for example outgoing plane) of at least its one side of polarization conversion element 10 is formed concavo-convex, and then polarization conversion element 10 has discrete (discontinuous) variable thickness to distribute at Zhou Fangxiang.But, be not limited to this, as polarization conversion element 10 has the thickness distribution of approximately discontinuous variation at Zhou Fangxiang, at least its one side (for example outgoing plane) of polarization conversion element 10 can form curved surface shape.

Again, in above-described embodiment, utilize the primary element of 88 fan shapes cutting apart of the effective coverage of corresponding wheel belt shape, form polarization conversion element 10.But, be not limited to this, can for example utilize the primary element of 8 fan shapes that 8 of corresponding circle shape effective coverage cuts apart, or utilize the primary element of 44 fan shapes cutting apart of the effective coverage of corresponding circle shape or wheel belt shape, or utilize the primary element of 16 16 fan shapes cutting apart of the effective coverage of corresponding circle shape or wheel belt shape to form polarization conversion element 10.That is, the effective coverage shape of polarization conversion element 10, effective coverage Segmentation Numbers (quantity of primary element) etc., can have multiple different variation.

Again, in above-described embodiment, the brilliant various primary element 10A～10D (and then polarization conversion element 10) that form of water.But, be not limited to this, use active other suitable optical materials can form each primary element.Situation, also can be used correspondence to use the light of wavelength to have the optical material of optically-active energy more than 100 degree/mm therewith.That is, if use the little optical material of optically-active energy, the required thickness that obtain the desired rotation angle of polarization direction can be blocked up, and due to the former of light loss thereby not good.

Again, in above-described embodiment, the corresponding illumination path of polarization conversion element 10 is fixing to be set, and also can make the corresponding illumination path of polarization conversion element 10 can insert de-setting.Again, in above-described embodiment, although the S polarisation of wafer W is combined into example with wheel band illumination group relatively, the also multipole illumination of the S polarisation of wafer W and 2 utmost points or 4 utmost points etc. and circular illumination combination relatively.In above-described embodiment, toward the lighting condition of cover curtain M and image-forming condition (numerical aperture and aberration) toward wafer W, such as the kind of the pattern of cover curtain M etc., therefore can automatically set again.

Fig. 9 illustrates the variation schematic diagram that a plurality of polarization conversion elements can exchange.Again, the distortion of Fig. 9 has the example similar structure of embodiment as shown in Figure 1, and its discrepancy is that it has the turntable 10T (turret) that a plurality of polarization conversion elements can be exchanged.

The turntable 10T that Figure 10 illustrates as the exchange mechanism of Fig. 9 is loaded multiple polarization conversion element 10a～10e schematic diagram.As shown in Figures 9 and 10, for variation, upper as the rotatable turntable 10T of axle with optical axis AX parallel direction, the polarization conversion element 10a～10e of multiple kind is set, utilize the turning effort of turntable 10T can exchange the polarization conversion element 10a～10e of multiple kind.Again, in Fig. 9, among the polarization conversion element 10a～10e of multiple kind, polarization conversion element 10a only, 10b is shown in figure.Again, for the exchange mechanism as polarization conversion element, be not limited to turntable 10T, for example sliding part also can.

Figure 11 A～11E illustrates multiple polarization conversion element 10a～10e and divides other structural representation.In Figure 11 A, the 1st polarization conversion element 10a has the structure identical with the polarization conversion element 10 of the embodiment shown in Fig. 5.In Figure 11 B, the 2nd polarization conversion element 10b, although have the similar structure with polarization conversion element 10a shown in Figure 11 A, difference is in middle section 10E, to be provided with polarisation to clear up the material 104c of portion.This polarisation is cleared up the material 104c of portion, has and the depolariser 4c same structure shown in Fig. 1, and has the function that the light of the linear polarization of incident is transformed into the light of non-polarized condition.

In Figure 11 C, the 3rd polarization conversion element 10c has the similar structures with polarization conversion element 10a shown in Figure 11 A, and the size that difference is middle section 10E is large (width of the 1st～4th primary element 10A～10D is narrower).Again, in Figure 11 D, the 4th polarization conversion element 10d has the similar structures with polarization conversion element 10c shown in Figure 11 C, and discrepancy is that middle section 10E arranges polarisation and clears up the material 104c of portion.

In Figure 11 E, the 5th polarization conversion element 10e, is consisted of 8 primary elements, but is consisted of 6 primary element 10C, 10F, 10G combination.The 5th polarization conversion element 10e, with the optical axis AX as all, as center, there is the effective coverage of wheel belt shape, and the effective coverage of this wheel belt shape is with optical axis AX as center, and utilization is slit into 6 fan shape primary element 10C, 10F, 10G at circumferencial direction decile and is configured.At these 6 fan shape primary element 10C, 10F, 10G, clip a pair of primary element phase mutual identical characteristics that optical axis AX is relative.That is, 6 primary element 10C, 10F, 10G, along the thickness (length of optical axis direction) that sees through direction (Y-direction) of light mutually each other different 3 kind primary element 10C, 10F, 10G respectively containing 2.

Then, primary element 10C, has identical function portion material with the 3rd primary element 10C shown in Fig. 7, and omits its function explanation.Primary element 10F, has been set thickness d F, has the linear polarization incident situation of polarization direction in Z direction, and Z direction makes the directions of rotation+150 degree around Y-axis, and being Z direction penetrates the light of linear polarization of polarization direction of the directions of rotation-30 degree around Y-axis.Primary element 10G, has been set thickness d G, has the linear polarization incident situation of polarization direction in Z direction, and Z direction makes the light of linear polarization of the polarization direction of rotation+30 degree directions penetrate around Y-axis.Again, replace middle section 10E, polarisation also can be set and clear up the material 104c of portion.

Again, get back to Figure 10, in the upper setting of turntable 10T, do not load the peristome 40 of polarization conversion element, for the situation that is not the polarizing illumination of Zhou Fangxiang polarizing illumination, the situation of carrying out the non-polarizing illumination of large σ value (the cover curtain side numerical aperture of the cover curtain side numerical aperture/projection optical system of σ value=illumination optics device), this peristome 40 is arranged in illumination path.

Again, as above-mentioned, loaded in the central portion of polarization conversion element 10a～10e of turntable 10T, although take by the opening of toroidal or do not have active material to form middle section 10E or arrange polarisation clear up the material 104c of portion as illustration it, also can configure and middle section 10E or polarisation are not set clear up the polarization conversion element of the material 104c of portion (polarization conversion element being formed by the primary element of fan shape).

Figure 12 A～12C illustrates an illustration intention of the secondary souce that utilizes the effect of polarization conversion element to be configured to Zhou Fangxiang polarized condition.In Figure 12 A～12C, for holding intelligible polarization conversion element, redraw in diagram again.

Figure 12 A, replace diffractive optical elements 5, in far field, the diffractive optical elements (light beam conversion element) of the light intensity distributions of (or Fraunhofer diffraction region) formation 8 utmost point shapes is arranged in light path, and polarization conversion element 10a or 10b are arranged at the situation of illumination path, with the secondary souce 33 of 8 utmost point shapes, show it.Therefore, the light beam of the secondary souce 33 by 8 utmost point shapes is configured to Zhou Fangxiang polarized condition.For Zhou Fangxiang polarized condition, respectively by forming the light beam of 8 border circular areas 33A～33D of the secondary souce 33 of 8 utmost point shapes, by 8 border circular areas 33A～33D, being combined into round circumferencial direction, is the linear polarization state of the polarization direction approximately consistent with the tangential direction of the circle of these 8 border circular areas 33A～33D combinations.Again, in Figure 12 A, although the secondary souce 33 of 8 utmost point shapes with 8 border circular areas illustrations that 33A～33D is configured to it, be not limited to 8 region shapes for circular.

Figure 12 B, replace diffractive optical elements 5, in far field, the diffractive optical elements (light beam conversion element) of the light intensity distributions of (or Fraunhofer diffraction region) formation 4 utmost point shapes is arranged in light path, and polarization conversion element 10c or 10d are arranged at the situation of illumination path, with the secondary souce 34 of 4 utmost point shapes, show it.Therefore, the light beam of the secondary souce 34 by 4 utmost point shapes is configured to Zhou Fangxiang polarized condition.For Zhou Fangxiang polarized condition, respectively by forming the light beam of 4 region 34A, 34C of the secondary souce 34 of 4 utmost point shapes, by 4 region 34A, 34C, being combined into round circumferencial direction, is the linear polarization state of the polarization direction approximately consistent with the tangential direction of the circle of these 4 region 34A, 34C combination.Again, in Figure 12 B, although the secondary souce 34 of 4 utmost point shapes with 4 elliptical region 34A, illustration that 34C is configured to it, be not limited to 4 region shapes for oval.

Figure 12 C, replace diffractive optical elements 5, in far field, the diffractive optical elements (light beam conversion element) of the light intensity distributions of (or Fraunhofer diffraction region) formation 6 utmost point shapes is arranged in light path, and polarization conversion element 10e is arranged at the situation of illumination path, with the secondary souce 35 of 6 utmost point shapes, show it.Therefore, the light beam of the secondary souce 35 by 6 utmost point shapes is configured to Zhou Fangxiang polarized condition.For Zhou Fangxiang polarized condition, respectively by forming 6 region 35C, 35F of the secondary souce 35 of 6 utmost point shapes, the light beam of 35G, by 6 region 35C, 35F, 35G, being combined into round circumferencial direction, is the linear polarization state of the polarization direction approximately consistent with the tangential direction of the circle of these 6 region 35C, 35F, 35G combination.Again, in Figure 12 C, although the secondary souce 35 of 6 utmost point shapes with 6 about trapezoidal shape region 35C, 35F, illustration that 35G is configured to it, being not limited to 6 region shapes is about trapezoidal shape.

Again, in above-described embodiment and variation, although polarization conversion element is fixed around optical axis, polarization conversion element also can make rotation around optical axis.Figure 13 is the structure skeleton diagram of being arranged to around the rotatable polarization conversion element 10f of optical axis.

In Figure 13, polarization conversion element 10f, is constituted by 4 primary element 10A, 10C.Polarization conversion element 10f has as the wheel belt shape effective coverage centered by all optical axis AX, and this wheel belt shape effective coverage centered by optical axis AX at halved primary element 10A, the 10C that is slit into 4 fan shape of circumferencial direction.In these 4 primary element 10A, 10C, clip a pair of primary element phase mutual identical characteristics that optical axis AX is relative.That is, 4 primary element 10A, 10C, along light through the thickness (length of optical axis direction) of direction (Y-direction) mutually each other different 2 kinds of primary element 10A, 10C respectively containing 2.

In this, because primary element 10A is that have portion's material of identical function, primary element 10C with the 1st primary element 10A shown in Fig. 7 be to have portion's material of identical function with the 3rd primary element 10C shown in Fig. 7, and omit its function explanation.Again, replacement middle section 10E's, polarisation also can be set and clear up the material 104c of portion.

This polarization conversion element 10f, sets for and can rotate as center with optical axis AX, and for example make centered by optical axis AX+45 degree or-45 degree can rotate.Figure 14 A～14C illustrates the effect that utilizes polarization conversion element 10f, is configured to an illustration intention of the secondary souce of Zhou Fangxiang polarized condition.Again, in Figure 14, be easy understanding, polarization conversion element 10f repeats to illustrate.

Figure 14 A, replace diffractive optical elements 5, in far field, the diffractive optical elements (light beam conversion element) of the light intensity distributions of (or Fraunhofer diffraction region) formation 2 utmost point shapes is arranged in light path, and polarization conversion element 10f is the state (normal condition) of 0 degree in the anglec of rotation, and the secondary souce 36 (36A) with 2 utmost point shapes under the situation in being arranged at illumination path shows it.In this, the light beam by secondary souce 36 (36A) is set to longitudinal direction polarization direction.

Figure 14 B, replace diffractive optical elements 5, in far field, the diffractive optical elements (light beam conversion element) of the light intensity distributions of (or Fraunhofer diffraction region) formation 4 utmost point shapes is arranged in light path, and polarization conversion element 10f is the state (normal condition) of 0 degree in the anglec of rotation, and the secondary souce 37 with 4 utmost point shapes under the situation in being arranged at illumination path shows it.In this, the light beam by secondary souce 37 is set to Zhou Fangxiang polarization direction.Again, in Figure 14 B, the light intensity distributions of 4 utmost point shapes is confined to upper and lower (Z direction) and left and right directions (directions X) in paper.

In Zhou Fangxiang polarized condition, respectively by forming the light beam of 4 border circular areas 37A, 37C of the secondary souce 37 of 4 utmost point shapes, the circumferencial direction of the circle being combined into by these 4 border circular areas 37A, 37C is the linear polarization state that has the polarization direction that the tangential direction of the circle being combined into these 4 border circular areas 37A, 37C is approximately consistent.Again, in Figure 14 B, although be that secondary souce 37 with 4 utmost point shapes is consisted of 4 border circular areas 37A, 37C and shows it, the shape in 4 regions is not defined as circle.

Figure 14 C, the diffractive optical elements that replaces Figure 14 B, in far field (or Fraunhofer diffraction region) limitation paper+-45 spend (+135 spend) direction in 45 degree (135 degree) directions and paper, the diffractive optical elements (light beam conversion element) that forms the light intensity distributions of 4 utmost point shapes is arranged in light path, and polarization conversion element 10f is state (the relative datum state of+45 degree in the anglec of rotation, the states of clockwise rotation 45 degree) make rotation and be arranged under the situation in illumination path, with the secondary souce 38 of 4 utmost point shapes, showing it.

In Figure 14 C, 1/2 wavelength plate 4b in polarized condition switching part 4 makes rotation around optical axis, and polarization conversion element 10f, makes+45 degree the linear polarization incident of (135 degree direction) polarization direction relatively.In this, because primary element 10A has the polarization direction of the linear polarization of the incident of making only to spend the function of (n is integer) in Rotate 180 degree ± n * 180, and primary element 10C has the polarization direction function of 90-degree rotation ± n * 180 degree (n is integer) only that makes incident linear polarization, the light beam of the secondary souce 38 by 4 utmost point shapes is set to Zhou Fangxiang polarized condition.

In the Zhou Fangxiang polarized condition shown in Figure 14 C, respectively by forming the light beam of 4 border circular areas 38B, 38D of the secondary souce 38 of 4 utmost point shapes, the circumferencial direction of the circle being combined into by these 4 border circular areas 38B, 38D is the linear polarization state that has the polarization direction that the tangential direction of the circle being combined into these 4 border circular areas 38B, 38D is approximately consistent.Again, in Figure 14 C, although be that the example that the secondary souce 38 with 4 utmost point shapes is consisted of 4 border circular areas 38B, 38D shows it, the shape in 4 regions is not defined as circle.

So, utilize the change action of the polarization direction of polarized condition switching part 4, turning effort with polarisation switching device 10f, although be confined to+45 degree of 4 utmost point shape secondary souces (135 degree) direction and-45 degree (+135 degree) direction, although it is direction in length and breadth that 4 utmost point shape secondary souces are confined to 0 degree (+180 degree) direction and 90 degree (270 degree), although it is direction in length and breadth that 2 utmost point shape secondary souces are confined to 0 degree (+180 degree) direction or 90 degree (270 degree), also can realize Zhou Fangxiang polarized condition.

Again, with optical axis AX as center halved the cutting of circumferencial direction and by the polarization conversion element that the primary element of 8 fan shapes forms, also can rotate around optical axis AX.As shown in Figure 15 A, the polarization conversion element for example being formed by 8 primary elements of cutting apart (for example polarization conversion element 10a), if make only to rotate+45 degree around optical axis AX, respectively by forming the light beam of 8 border circular areas 39A～39D of 8 utmost point shape secondary souces 39, the circumferencial direction (tangential direction of the circle that 8 border circular areas 39A～39D are combined into) with the circle being combined into relative to these 8 border circular areas 39A～39D makes only to rotate the linear polarization state of-45 polarization directions of spending.

Again, as shown in Figure 15 B, respectively by forming the light beam of 8 border circular areas of 8 utmost point shape secondary souces, there iing the circumferencial direction of the circle that relatively these 8 border circular areas are combined into (tangential direction of the circle that 8 border circular areas are combined into), long axis direction is by the situation of the elliptical polarized light of the polarization direction that only rotation+45 is spent, polarization conversion element as shown in Figure 15 A (for example polarization conversion element 10a), utilization makes only to rotate+45 degree around optical axis AX, as shown in Figure 15 C, can obtain about Zhou Fangxiang polarized condition.

Figure 16 illustrates that polarization conversion element is configured near the pupil of lamp optical system in position, the positive anterior locations (near the position of light incident side) of circular cone prismatic mirror system 8 is the schematic diagram of example.In the example of Figure 16, utilize the multiple variation effect of flexible lens combination 9, be projected to the size of picture of the plane of incidence middle section 10E of micro-fly's-eye lens 11, can be changed with the size of picture of each primary element 10A～10D that is projected to the plane of incidence of micro-fly's-eye lens 11, action by circular cone prismatic mirror system 8, the picture of each primary element 10A～10D that is projected to the plane of incidence of micro-fly's-eye lens 11, the amplitude of the radial direction centered by optical axis AX is changed.

Therefore, there is the polarization conversion element of the middle section 10E of variation (or polarisation is cleared up the material 104c of portion) as shown in figure 16, compared with there being the optical system (flexible lens 9) of conversion multiplying power effect, be arranged on the situation of light source side, consider that middle section 10E occupies region and utilizes the conversion multiplying power of flexible lens 9 and be changed, also can determine the size of middle section 10E.

Again, variation as shown in figure 16, at the polarization conversion element that has middle section 10E (or polarisation is cleared up the material 104c of portion), compared with there being change wheel band to liken the optical system (circular cone prismatic mirror system 8) of use to, be arranged on the situation of light source side, as shown in figure 17, at least one of better meeting the following conditions (1) and condition (2).

(1)(10in+ΔA)/10out＜0.75

(2)0.4＜(10i?n+ΔA)/10out.

Wherein,

10in: the effective radius of the middle section 10E of polarization conversion element 10,

10out: the outside effective radius of polarization conversion element 10,

Δ A: by there being change to take turns the increase part of the inner radius of the light beam of being with the optical system that likens use to.

In this, the situation of (1) does not satisfy condition, by polarization conversion element 10, make the region of the wheel belt shape that Zhou Fangxiang polarized condition is transformed narrow, because can not reach the wheel belt shape of steamboat band ratio or Zhou Fangxiang polarizing illumination that multipole shape secondary souce causes and bad.Again, the do not satisfy condition situation of (2), the diameter of the light beam of middle section that can be by polarization conversion element 10 obviously diminishes, for example, when this polarization conversion element 10 can not move from illumination path, polarized condition is constant, bad because there not being little σ illumination.

Again, as shown in figure 18, polarization conversion element is configured near the position of pupil of lamp optical system, compared with micro-fly's-eye lens 11, is the positions in cover curtain side, particularly, also can be arranged on the picture of cover curtain shield 14 is projected to near the position pupil of the imaging optical system 15 on cover curtain.At the embodiment shown in Figure 16 and Figure 18, identical to the embodiment of Figure 11 with Fig. 9, also can there be a plurality of permutable polarization conversion elements.

Again, at above-described embodiment, compared with polarization conversion element 10, when the optical system of wafer W side (lamp optical system and projection optical system) has the situation of polarisation aberration (delay), due to polarisation aberration, polarization direction can change.In this situation, in the impact of polarisation aberration of considering this optical system, utilize polarization conversion element 10, the better direction that can set the plane of polarisation being rotated.Again, utilize polarization conversion element 10, in the light path of wafer W side, be configured the situation of reflecting part material, by this reflecting part material, be reflected in each polarization direction and produce phase differential.Now, consider the light beam phase differential that the polarized light property by reflecting surface causes, utilize polarization conversion element 10 also can set the direction of the plane of polarisation being rotated.

The embodiment that comments metering method of polarized condition then, is described.In the present embodiment, maintenance is as the side of the crystal wafer platform (substrate stage) of the wafer W of photonasty substrate, and the wafer face polarisation monitor 90 that use can pass in and out, detects arrival as the polarized condition of the light beam of the wafer W of photonasty substrate.Again, wafer face polarisation monitor 90, also can be arranged in crystal wafer platform, and also this crystal wafer platform can be arranged on other instrumentation platform.

Figure 19 illustrates in order to detect the polarized condition of light of illumination wafer W and the structural representation of the wafer face polarisation monitor 90 of light intensity.As shown in figure 19, wafer face polarisation monitor 90, comprises position or near the pin hole portion material 91 it that can be positioned wafer W.The light of pin hole 91a by pin hole portion material 91, through being configured near the image planes position of projection optical system PL or its, as the aligning lens 92 of focal position, front side (collimated lens), become approximately parallel light beam, and after being reflected mirror 93 reflections, be incident in relay lens system 94 (relay lens).Approximately parallel beam through relay lens system 94, after 1/4 wavelength plate 95 and the polarisation optical splitter 96 as polarization element as phase shifts element, arrive the detection faces 97a of two-dimensional CCD 97 (Charge Coupled Device, charge-coupled image sensor).In this, the ejaculation pupil of the detection faces 97a of two-dimensional CCD 97 and projection optical system PL is optical conjugate roughly, so with the illumination pupil face of illumination optics device optical conjugate roughly.

1/4 wavelength plate 95, is configured and can, with optical axis as central rotation, for this 1/4 wavelength plate 95, be connected in order to be configured to the configuration part 98 as central rotation with optical axis.So, to the degree of polarization of the illumination light of wafer W, not 0 situation, by configuration part 98, make 1/4 wavelength plate 95 around optical axis rotation, and change in the detection faces 97a of two-dimensional CCD 97 light intensity distributions.Therefore, for wafer face polarisation monitor 90, one side is used configuration part 98 and is made 1/4 wavelength plate 95 make rotation around optical axis, and one side detects the variation in detection faces 97a light intensity distributions, and from then on testing result, to the method for utilizing rotatable phase moving meter, can be measured the polarized condition of illumination light.

Again, the method of rotatable phase moving meter, the described < < in crane field light pencil-give light operator's applied optics > >, as the detailed record of Co., Ltd.'s new technology communication (communications) for example.In fact, pin hole portion material 91 (and then pin hole 91a) makes two-dimensional movement along wafer face, in the polarized condition of a plurality of position finding illumination light of wafer face.Now, for wafer face polarisation monitor 90, because detect the variation in the light intensity distributions of two-dimensional detection face 97a, according to this detected Distribution Data, in the pupil of illumination light, can measure the distribution of polarized condition.

For wafer face polarisation monitor 90, as 1/4 wavelength plate 95 of phase shifts element, can replace and use 1/2 wavelength plate again.Use phase shifts element, polarized condition, be for measuring 4 Stokes parameters, variation is along the relative angle of the optical axis of phase shifts element and polarization element (polarisation optical splitter 96), make phase shifts element or polarization element back out from light path, the light intensity distributions going out at detection faces 97a at least 4 different state-detection according to need changes simultaneously.Again, in the present embodiment, although rotate around optical axis as 1/4 wavelength plate 95 of phase shifts element, also can make to rotate around optical axis as the polarisation optical splitter 96 of polarization element, the two rotates around optical axis also can to make phase shifts element and polarization element.Again, replace these operations or increase these operations, also can make from light path, to insert de-as the one of 1/4 wavelength plate 95 of phase shifts element and polarisation optical splitter 96 as polarization element or the two.

Again, for wafer face polarisation monitor 90, utilizing the polarized light property of catoptron 93, is the polarized condition that changes light.In this situation, because the polarized light property of the catoptron of knowing in advance 93, according to utilizing the resulting impact on the polarized condition of the polarized light property of catoptron 93 of needed calculating, the measurement result of revisal wafer face polarisation monitor 90, can and correctly measure the polarized condition of illumination light.Again, be not limited to catoptron, the situation that causes polarized condition by other opticses that change by lens etc., with revisal measurement result in the same manner, can correctly be measured the polarized condition of illumination light.

Below, illustrate the amount of commenting distributing about the polarized condition in the pupil of illumination light.First, by a bit (or tiny area) on pupil, and arrive the some light of (tiny area) in image planes, calculate one by one corresponding specific degree of polarization DSP.In following explanation, use the XYZ coordinate system of Fig. 1, Figure 16, Figure 18 again.A some picture element of (tiny area) corresponding two-dimensional CCD 97 on above-mentioned pupil, and a bit XY coordinate system of (tiny area) corresponding pin hole 91a in image planes.

This specific degree of polarization DSP, when a bit (or the tiny area) passing through on pupil, and the intensity of the directions X polarized component (polarisation of the direction of vibration of directions X on pupil) of the particular light ray of a bit (tiny area) in arrival image planes is Ix, when the intensity of the Y-direction polarized component of this particular light ray (polarisation of the direction of vibration of Y-direction on pupil) is Iy

(3)DSP＝(Ix-I?y)/(Ix+Iy)。

Again, this specific degree of polarization DSP, corresponding all strength S ₀horizontal linear polarisation intensity deduct vertical line polarisation strength S ₁, with (S ₁/ S ₀) identical.

Again, by a bit (or tiny area) of passing through on pupil, and the intensity of the directions X polarized component (polarisation of the direction of vibration of directions X on pupil) of the particular light ray of a bit (tiny area) in arrival image planes is Ix, and the intensity of the Y-direction polarized component of this particular light ray (polarisation of the direction of vibration of Y-direction on pupil) is Iy, by following formula (4), (5), can be defined in the specific polarizing coefficient RSP of horizontal polarisation (the diffraction light of the corresponding cover curtain pattern that horizontal direction is extended in pattern plane becomes the polarisation of S polarisation) _h, with the specific polarizing coefficient RSP of vertical polarisation (the diffraction light of the corresponding cover curtain pattern that vertical direction is extended in pattern plane becomes the polarisation of S polarisation) _v.

(4)RSP _h＝Ix/(Ix+I?y)，

(5)RSP _v＝Iy/(I?x+Iy)，

Wherein, RSP when desirable non-polarizing illumination _h, RSP _vthe two is 50%, RSP when desirable horizontal polarisation _hbe 100%, RSP when desirable vertical polarisation _vbe 100%.

Again, the corresponding light that arrives a bit (tiny area) in image planes by a bit (or tiny area) on pupil one by one, when in order to following formula (6)～(9) definition degree of polarization V, the corresponding light beam that arrives a bit (tiny area) in image planes by desired efficient light sources region, can define average degree of polarization V (Ave) with following formula (10).

(6)V＝(S ₁ ²+S ₂ ²+S ₃ ²) ^1/2/S ₀

＝(S ₁’ ²+S ₂’ ²+S ₃’ ²) ^1/2

(7)S ₁’＝S ₁/S ⁰

(8)S ₂’＝S ₂/S ₀

(9)S ₃’＝S ₃/S ₀

S wherein ₀for whole intensity, S ₁for horizontal linear polarisation intensity deducts vertical line polarisation intensity, S ₂be that 45 degree linear polarization intensity deduct 135 degree linear polarization intensity, S ₃for dextrorotation rotatory polarization intensity deducts left-handed rotatory polarization intensity.

(10)V(Ave)＝∑[S ₀(x _i，y _i).V(x _i，y _i)]/∑S ₀(x _i，y _i)。

Again, in formula (10), S ₀(x _i, y _i) be corresponding to desired efficient light sources region (x _i, y _i) on a bit (or tiny area) and arrive a bit whole strength S of the light of (tiny area) in image planes ₀, V (x _i, y _i) be corresponding to desired efficient light sources region (x _i, y _i) on a bit (or tiny area) and arrive some degree of polarization of the light of (tiny area) in image planes.

Again, the corresponding light that arrives a bit (tiny area) in image planes by desired efficient light sources region, can define the average specific polarizing coefficient RSP about horizontal polarisation with following formula (11) _h(Ave), with following formula (12), can define the average specific polarizing coefficient RSP about vertical polarisation _v(Ave).

(11)RSP _h(Ave)＝Ix(Ave)/(Ix+Iy)Ave

＝∑[S ₀(x _i，y _i).RSP _h(x _i，y _i)]/∑S ₀(x _i，y _i)，

(12)RSP _v(Ave)＝Iy(Ave)/(Ix+Iy)Ave

＝∑[S ₀(x _i，y _i).RSP _v(x _i，y _i)]/∑S ₀(x _i，y _i)，

Wherein Ix (Ave) passes through fixed efficient light sources region (x _i, y _i) and to arrive the light of a bit (tiny area) in image planes average in the intensity of directions X polarized component (polarisation of the direction of vibration of directions X on pupil), Iy (Ave) passes through fixed efficient light sources region (x _i, y _i) and to arrive the light of a bit (tiny area) in image planes average in the intensity of Y-direction polarized component (polarisation of the direction of vibration of Y-direction on pupil), RSP _h(x _i, y _i) be to pass through fixed efficient light sources region (x _i, y _i) and arrive a bit specific polarizing coefficient at horizontal polarisation of the light of (tiny area) in image planes, RSP _v(x _i, y _i) be to pass through fixed efficient light sources region (x _i, y _i) and arrive the specific polarizing coefficient at vertical polarisation of the light of a bit (tiny area) in image planes.Again, (Ix+Iy) Ave is that to pass through the intensity of whole light beams in fixed efficient light sources region average.

In this, RSP when desirable non-polarizing illumination _h(x _i, y _i), RSP _v(x _i, y _i) the two is 50%, RSP when desirable horizontal polarisation _h(x _i, y _i) be 100%, RSP when desirable vertical polarisation _v(x _i, y _i) be 100%.

Then, correspondence is passed through fixed efficient light sources region (x _i, y _i) and arrive the some light beam of (tiny area) in image planes, can define average specific degree of polarization DSP (Ave) with following formula (13).

(13)DSP(Ave)＝(Ix-Iy)Ave/(Ix+I?y)Ave

＝{∑[Ix(x _i，y _i)-Iy(x _i，y _i)]/∑[Ix(x _i，y _i)+Iy(x _i，y _i)]}

＝S ₁’(Ave)

＝{∑S ₁/∑S ₀}

In this, (Ix-Iy) Ave passes through fixed efficient light sources region (x _i, y _i) and the light beam that arrives a bit (tiny area) in image planes the intensity of directions X polarized component with on average pass through fixed efficient light sources region (x _i, y _i) and the light beam that arrives a bit (tiny area) in image planes the intensity of Y-direction polarized component differ average, Ix (x _i, y _i) be to pass through fixed efficient light sources region (x _i, y _i) and arrive the light beam of a bit (tiny area) in image planes at the intensity of directions X polarized component, Iy (x _i, y _i) be to pass through fixed efficient light sources region (x _i, y _i) and arrive the light beam of a bit (tiny area) in image planes at the intensity of Y-direction polarized component, S ₁' (Ave) be at fixed efficient light sources region (x _i, y _i) S ₁' composition average.

In formula (13), when desirable non-polarizing illumination, DSP (Ave) is 0, and when desirable horizontal polarisation, DSP (Ave) is 1, and when desirable vertical polarisation, DSP (Ave) is-1.

Now, the illumination optics device of the present embodiment, and then exposure device, at fixed efficient light sources region (x _i, y _i) average specific polarizing coefficient RSP _h(Ave), RSPv (Ave) meets

RSP _h(Ave)＞70％，RSP _v(Ave)＞70％，

Can see that be linear polarization in fixed efficient light sources region.In this, as average specific polarizing coefficient RSP _h(Ave), RSP _v(Ave) do not meet the situation of above formula condition, in the illumination of Zhou Fangxiang polarisation wheel band, or Zhou Fangxiang polarisation quadrupole illuminating, two utmost point illuminations of Zhou Fangxiang polarisation etc., in determined direction, there is plane of polarisation because be not desirable linear polarization state, for there being the thin pattern of the line width of particular orientation (pitch) direction can not upwards promote imaging capability.

Again, as shown in figure 13, use 4 to cut apart polarization conversion element 10 and carry out 4 situations of cutting apart the illumination of Zhou Fangxiang polarisation wheel band, as shown in figure 20, the secondary souce 31 of wheel belt shape is 4 to cut apart, average specific polarizing coefficient RSP that also can be to each cut zone 31A1,31A2,31C1,31C2 _h(Ave), RSP _v(Ave) amount of commenting.

Exposure device for above-described embodiment, by illumination optics device with illuminating cover curtain (cross mark) (illumination step), by using projection optical system by being formed on pattern that the transfer printing of cover curtain uses in photonasty base plate exposure (step of exposure), can manufacture microcomponent (semiconductor element, capturing element, liquid crystal display cells, thin-film electro magnetic head etc.).Below, use the exposure device of above-described embodiment, with the wafer as photonasty substrate etc., form circuit pattern, and the practical methods obtaining as the semiconductor element of microcomponent is example, with reference to the process flow diagram of Figure 21, explain.

First, in the step 301 of Figure 21, deposited metal film on the wafer of a batch.In next step 302, on the metal film on these wafers of batch, be coated with photoresist.Afterwards, in step 303, use the exposure device of above-described embodiment, make the picture of the pattern on cover curtain by projection optical system, each shooting area on the wafer of this batch, is exposed transfer printing in turn.Afterwards, in step 304, carry out after the photoresist developing on the wafer of this batch, in step 305, by the photoetching agent pattern on the wafer of this batch, as cover curtain, carry out etching, therefore, corresponding cover curtain is the circuit pattern of pattern above, is formed on each shooting area of each wafer.Afterwards, by carrying out formation of the circuit pattern on upper strata more etc., make the element of semiconductor element etc. manufactured.Manufacture method according to above-mentioned semiconductor element etc., has the semiconductor element of atomic thin circuit pattern can have good production capacity.

Again, for the exposure device of above-described embodiment, utilize at dull and stereotyped (glass substrate) above, form fixed pattern (circuit pattern, electrode pattern etc.), can obtain the liquid crystal display cells as microcomponent.Below, with reference to the process flow diagram of Figure 22 as an example explanation.At Figure 22, in pattern, form step 401, use the exposure device of above-described embodiment, at the pattern of photonasty substrate (the applied glass substrate that has photoresist etc.) transfer printing exposure cover curtain, so-called micro-photographing process is carried out.Utilize this micro-photographing process step, on photonasty substrate, contain the fixed patterns such as a plurality of electrodes and be formed.Afterwards, the substrate being exposed, utilizes through development step, and etching step removes each step of photoresist step etc., and pattern fixed on substrate is formed, and then carries out chromatic filter (color filter) and forms step 402.

For chromatic filter, form step 402,3 points of corresponding red, green, blue are one group, are formed many rectangular assortments, or the light filter of 3 of red, green, blue is that an assembly is listed as into a plurality of horizontal scanning line directions, and form chromatic filter.Then,, after chromatic filter forms step 402, unit combination step 403 is carried out.In unit combination step 403, be assembled with the substrate that is formed resulting the determined pattern of step 401 by pattern, and use by chromatic filter and form chromatic filter that step 402 obtains etc., and obtain liquid crystal panel (liquid crystal cells).

Unit combination step 403, for example, is being formed the substrate of resulting the determined pattern of step 401 by pattern, and uses and to be formed between the resulting chromatic filter of step 402 and to be injected liquid crystal by chromatic filter, and manufacture liquid crystal panel (liquid crystal cells).Afterwards, in the combination step 404 of module, the circuit of the display action of the liquid crystal panel being combined (liquid crystal cells), each parts of backlight module etc. are installed, and have made as liquid crystal display cells.According to the manufacture method of above-mentioned liquid crystal display cells, can obtain the liquid crystal display part of atomic thin circuit pattern, and make it have good production capacity.

Again, for above-described embodiment, as the light of exposure, although use KrF excimer laser light (wavelength 248nm) or ArF excimer laser light (wavelength 193nm), but be not limited to this, the light source that other are applicable, for example, supply with the F of the laser light of wavelength 157nm ₂lASER Light Source etc., also can be suitable for the present invention.Moreover for above-described embodiment, the exposure device that comprises illumination optics device is that example explains, still for the general illumination optical devices of the plane of illumination beyond illuminating cover curtain or wafer, known ground, also can be used the present invention.

In above-described embodiment, in the light path between projection optical system and photonasty substrate, also can use and fill up the method that refractive index is more than or equal to 1.1 medium (typical liquid), i.e. so-called immersion method again.In this situation, as the method for filling up liquid in the light path between projection optical system and photonasty substrate, can adopt revealed part in international publication number WO99/49504 to fill up liquid, the platform that Unexamined Patent 6-124873 also discloses the substrate that keeps exposure object makes mobile method in liquid bath, Japanese patent laid-open 10-303114 is also disclosed in the liquid bath that forms institute's depthkeeping degree on platform, and keeps therein the method for substrate etc.

Again, as liquid, better use can have penetrability and high index of refraction to the light of exposure, and the applied photoresistance of relative projection optical system and substrate surface is stable liquid, the situation as the light of exposure with KrF excimer laser light or ArF excimer laser light for example, can be used pure water, deionized water as liquid.Use the F as the light of exposure again, ₂the situation of laser, can be used and can see through F as having of liquid ₂laser light, such as the fluorine prime system liquid of fluorine prime system oil or fluorinated polyether (PFPE) etc.

Claims (24)

1. a polarization conversion element, the polarized condition of the incident light that can be used in combination with lamp optical system and the light path along described lamp optical system be advanced is transformed into a fixed polarized condition, and described polarization conversion element is characterised in that:

Described polarization conversion element has divided a plurality of region on Zhou Fangxiang;

This polarization conversion element utilizes active optical material to form, and has the thickness distribution changing at Zhou Fangxiang;

Wherein, this thickness distribution is configured to:

Making to have the described incident light of linear polarization state of the polarization direction of single direction, in each of described a plurality of regions, be transformed into promising Zhou Fangxiang polarization direction Zhou Fangxiang polarized condition light or have the light in the footpath direction polarized condition of the polarization direction of radial direction;

The optical axis that this polarization conversion element is arranged to using along described lamp optical system can turn round as center.

2. polarization conversion element according to claim 1, is characterized in that the thickness in any 2 regions adjacent in those regions is wherein different.

3. polarization conversion element according to claim 2, is characterized in that wherein relative any 2 regions in those regions, has equal optically-active angle.

4. polarization conversion element according to claim 3, is characterized in that wherein these relative any 2 regions, has equal thickness.

5. polarization conversion element according to claim 4, is characterized in that wherein each those region, is fan shape.

6. polarization conversion element according to claim 1, is characterized in that wherein forming the optical material of this polarization conversion element, is that the crystalline material that is configured to the direct of travel of incident light by crystal optics axle is formed.

7. polarization conversion element according to claim 1, is characterized in that wherein this polarization conversion element is arranged to freely to insert from this fixed light path de-.

8. an illumination optical apparatus, is characterized in that comprising:

Polarization conversion element described in any one of claim 1 to 7, described polarization conversion element is arranged to freely to insert from the light path of illumination light de-.

9. illumination optical apparatus according to claim 8, is characterized in that wherein this polarization conversion element, is configured near the pupil or pupil of this illumination optical apparatus.

10. illumination optical apparatus according to claim 8, is characterized in that wherein more comprising a phase section, is configured in the light path of light incident side of this polarization conversion element, and making corresponding incident is that the polarization direction of the light of linear polarization state changes.

11. illumination optical apparatus according to claim 10, is characterized in that wherein this phase section has one 1/2 wavelength plates, can, on the crystal optics axle of the optical axis center as aforementioned illumination optical apparatus, rotate freely.

12. illumination optical apparatus according to claim 10, is characterized in that wherein more comprising one the 2nd phase section, are configured in the light path of light incident side of this phase section, make the light of the elliptical polarized light state of incident, are transformed into the light of linear polarization state.

13. illumination optical apparatus according to claim 12, is characterized in that wherein the 2nd phase section has one 1/4 wavelength plates, can, on the crystal optics axle of the optical axis center as aforementioned illumination optical apparatus, rotate freely.

14. illumination optical apparatus according to claim 8, is characterized in that wherein more comprising and take turns band than change optical system, to change the wheel band ratio of the secondary souce of the pupil that is formed on this illumination optical apparatus.

15. illumination optical apparatus according to claim 14, is characterized in that wherein this polarization conversion element, are configured in this and take turns band than in the light path of the light incident side of change optical system, meet:

(10in+ΔA)/10out＜0.75

0.4 < (10in+ Δ A)/10out, wherein

10in: the effective radius of the middle section of described polarization conversion element,

10out: the outside effective radius of described polarization conversion element,

Δ A: take turns band than the increase part of the inner radius of the light beam that changes optical system by described.

16. illumination optical apparatus according to claim 8, is characterized in that wherein forming the optical material of this polarization conversion element, are that the crystalline material that is configured to the direct of travel of incident light by crystal optics axle is formed.

17. 1 kinds of illumination optical apparatus, are the illumination optical apparatus that plane of illumination is thrown light on, and described illumination optical apparatus is characterised in that and comprises:

Polarization conversion element, the polarized condition of the incident light that the light path along illumination light is advanced is transformed into a fixed polarized condition;

This polarization conversion element has divided a plurality of region on Zhou Fangxiang,

This polarization conversion element utilizes active optical material to form, and has the thickness distribution changing at Zhou Fangxiang;

This polarization conversion element will have the described incident light of linear polarization state of the polarization direction of single direction, in each of described a plurality of regions, be transformed into promising Zhou Fangxiang polarization direction Zhou Fangxiang polarized condition light or have the light in the footpath direction polarized condition of the polarization direction of radial direction;

The optical axis that this polarization conversion element is arranged to using along described illumination optical apparatus can turn round as center.

18. illumination optical apparatus according to claim 17, it is characterized in that comprising:

The 1st light beam conversion element, is configured in the light path of illumination light, by the light intensity distributions in the section direction of incident light, is transformed into the light intensity distributions of the wheel belt shape different from described light intensity distributions;

The 2nd light beam conversion element, replaceable the 1st light beam conversion element, the 2nd light beam conversion element, by the light intensity distributions in the section direction of incident light, is transformed into the light intensity distributions of the multipole shape different from described light intensity distributions.

19. 1 kinds of exposure devices, is characterized in that comprising:

Illumination optical apparatus claimed in claim 8, by this illumination optical apparatus by fixed pattern exposure to photonasty substrate.

20. an exposure method, is characterized in that comprising:

Right to use requires the illumination optical apparatus described in 8, by fixed pattern exposure to photonasty substrate.

21. 1 kinds of manufacturing methods, is characterized in that comprising:

Right to use requires the illumination optical apparatus described in 8, by fixed pattern exposure to the step on photonasty substrate; And

The step that the described photonasty substrate having exposed is carried out to video picture.

22. 1 kinds of exposure devices, is characterized in that comprising:

Illumination optical apparatus described in claim 17～18 any one, by this illumination optical apparatus by fixed pattern exposure to photonasty substrate.

23. 1 kinds of exposure methods, is characterized in that comprising:

Right to use requires the illumination optical apparatus described in 17～18 any one, by fixed pattern exposure to photonasty substrate.

24. 1 kinds of manufacturing methods, is characterized in that comprising:

Right to use requires the illumination optical apparatus described in 17～18 any one, by fixed pattern exposure to the step on photonasty substrate; And

The step that the described photonasty substrate having exposed is carried out to video picture.