CN203133474U - Device for online detection of wave aberration of projection objective - Google Patents

Abstract

The utility model discloses a device for online detection of wave aberration of a projection objective. The device comprises a laser source (LA), the projection objective (PO), a reference mark (RP), a detector (DE) and a mask plate (MA). The mask plate (MA) is used for converting the laser emitted from the laser source (LA) into two beams of coherent light; the two beams of coherent light are interfered with each other on a focal plane of the projection objective (PO) to produce interference fringes after passing through the projection objective (PO); the interference fringes irradiate onto the detector (DE) to be converted into electrical signals after passing through the reference mark (RP); the position offset of the interference fringes is obtained according to the intensity of the electrical signals; and then the wave aberration of the projection objective (PO) can be obtained according to the size of the offset. The device disclosed by the utility model can be used for measuring all the 37 Zernike coefficients, simplifying the test process and the wave aberration calculation, and improving the measurement accuracy.

Description

On-line detection device of wave aberration of projection lens

Technical field

The utility model optical recording technical field is specifically related to the wave aberration on-line measurement device of the projection objective of litho machine, particularly based on the on-line detection device of wave aberration of projection lens of two-beam interference.

Background technology

The wave aberration of projection objective can influence the image quality of exposure lines, can influence the resolving power of litho machine as spherical aberration, and coma can influence asymmetry and the alignment precision of lines, and astigmatism can influence the imaging lines unevenness of X, Y both direction.Along with the litho machine characteristic dimension is more and more littler, wave aberration to projection objective requires also more and more stricter, not only require rudimentary aberration (as spherical aberration, coma and astigmatism) very little, but also strict requirement is proposed senior aberration (up to 37 Zernike coefficients), this just requires projection objective wave aberration on-line measurement device can measure whole wave aberrations simultaneously, in order to adjust the wave aberration of projection objective in real time, to satisfy the demand of photoetching process.

Prior art 1 (Hans van der laan, Marcel Dierichs, Henk van Greevenbroek, etc. " Aerial image measurement methods for fast aberration set-up and illumination pupil verification ", Proc.SPIE2001,4346,394-407) a kind of measuring method based on transmission image-position sensor (TIS) has been proposed, TIS is made up of measurement markers and square hole and light intensity detector, square hole is used for the variation of measurement light source intensity, be used for the normalization measuring-signal, to eliminate intensity of light source fluctuation to the influence of measurement result.The light beam irradiates measurement markers of different light illumination modes, because be subjected to the influence of projection objective wave aberration, the horizontal level of imaging mark and upright position can change, utilize light intensity detector to measure the position offset of marker image, the position that the recycling software emulation goes out can obtain the wave aberration of projection objective to the sensitivity matrix of wave aberration.It is simple in structure that this method is measured wave aberration, is easy to be integrated in litho machine inside, but can only measure the rudimentary aberration (rudimentary Zernike coefficient) of projection objective, comprise spherical aberration (Z4, Z9, Z16), directions X coma (Z2, Z7, Z14), Y-direction coma (Z3, Z8, Z15) and astigmatism (Z5, Z12, Z21), can not measure whole 37 Zernike coefficients.

The patent US6646729B2 of ASML company utilizes FOCAL (FOcus CALibration use alignment system) technology and DISTO (Distortion-measuring technique) technology, measure the vertical and horizontal offset of marker image, obtain the wave aberration of projection objective, the patent CN100474115C of Shanghai Microelectronic Equipment Co., Ltd (SMEE), CN1312464C, CN101241312B, and the patent CN100428058C of Shanghai optical precision optical machinery research institute, CN100561359C, CN101551594B improves prior art 1 in mask design and method of testing, improve the measuring accuracy of wave aberration, but still can not measure whole 37 Zernike coefficients.

In order accurately to detect the rudimentary and senior wave aberration of projection objective, NIKON company proposes a kind of AIS technology (prior art 2:Jacek.K.Tyminski, Tsuneyuki Hagiwara, Naoto Kondo, etc.Aerial Image Sensor:In-Situ Scanner Aberration Monitor.Proc.Of SPIEVol.6152), it is under high coherent light illumination condition, irradiation has (0 ° of different cycles and different directions, 30 °, 45 °, 90 °, 120 °, 135 °) the mask plate of 36 kinds of grating markers, go out not at the same level time light through the beam diffraction of grating, utilize+1,-1 and 0 grade of interference of light obtains the picture of grating marker, utilize detector to obtain the physical location of grating picture, the calculating picture departs from the ideal picture, and recycling partial coherence imaging theory obtains the wave aberration of projection objective.The grating marker of different cycles different directions is finished the measurement to whole pupil plane wave aberration, therefore can obtain whole 37 the Zernike coefficients of projection objective, but the label orientation of reference needs that also a plurality of directions are arranged on this technical requirement detector, require work stage to survey along a plurality of scanning directions, performance requirement height to detector and work stage, in addition, wave aberration retrieving algorithm complexity is difficult for improving measuring accuracy.

The utility model content

(1) technical matters that will solve

Technical problem to be solved in the utility model is the on-line measurement device that proposes a kind of projection objective wave aberration for litho machine, the rudimentary aberration of projection objective can only be measured to overcome prior art, or whole aberrations can be measured but the shortcoming of measurement flow process and method complexity.

(2) technical scheme

For solving the problems of the technologies described above, the utility model proposes a kind of on-line detection device of wave aberration of projection lens, comprise light source, projection objective, reference marker and detector, described light source is used for shoot laser, described device also comprises mask plate, incides described projection objective by described light source emitting laser after via this mask plate; Described mask plate comprises the test badge that is used to form interference fringe, and test badge constitutes the phase grating pattern; Described reference marker is arranged on the focal plane place of described projection objective, constitutes the amplitude grating pattern, and the cycle of this amplitude grating is the twice of the phase grating of described test badge, and the ratio of its size and the size of phase grating is the enlargement factor of projection objective; Described detector is arranged on the rear of reference marker in the described light path; Wherein, described mask plate is used for and will be converted to two bundle coherent lights by described light source emitting laser, and this two bundles coherent light place, focal plane at described projection objective behind described projection objective interferes, and produces interference fringe; This interference fringe is radiated on the described detector through behind the described reference marker, is converted into electric signal; According to the intensity of this electric signal, can obtain the position offset of described interference fringe, obtain the wave aberration of described projection objective again according to the big I of side-play amount.

(3) beneficial effect

The measurement mechanism of projection objective wave aberration of the present utility model can be measured whole 37 Zernike coefficients by double beam interferometry, has simplified testing process and wave aberration computing method, has improved measuring accuracy.

Description of drawings

Fig. 1 is wave aberration of photo-etching machine projection objective pick-up unit synoptic diagram;

Fig. 2 is the index path that mask plate produces vertical and inclination coherent light;

Fig. 3 is that the wave aberration of coherent light vertical irradiation when phase grating measured index path;

Fig. 4 causes interference image and desirable image position deviation because of aberration;

Fig. 5 is that the wave aberration of coherent light oblique illumination when phase grating measured index path;

Fig. 6 is the spatial distribution map of phase grating on the mask plate;

The synoptic diagram of all the light beam projecting points when Fig. 7 is diffracted beam through pupil plane to the wave aberration uniform sampling on the pupil plane;

Fig. 8 is the index path that microprism array changes the coherent light incident angle.

Embodiment

For making the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the utility model is described in further detail.

Fig. 1 is the structural representation of wave aberration of photo-etching machine projection objective on-line measurement device of the present utility model.Shown in Figure 1 as Fig. 1, this device comprises light source LA, illuminator IL, mask plate MA, projection objective PO, reference marker RP, detector DE and work stage ST.Light source LA is used for emission laser, the laser that it is launched shines on the illuminator IL through mirror M I, illuminator IL expands this laser, impinge upon on the mask plate MA after the shaping, homogenising, one cover illumination path is arranged on the mask plate MA, the illuminating bundle of partial coherence is converted to two bundle coherent lights, interfere at the place, focal plane of projection objective PO behind this two bundles coherent light process projection objective PO, produce interference fringe.Reference marker RP is arranged on the focal plane place of projection objective PO, and detector DE is arranged on the rear of reference marker RP in the laser optical path, and reference marker RP and detector DE are installed in movably on the work stage ST jointly.

Mask plate MA comprises the test badge that is used to form interference fringe, test badge can constitute a kind of phase grating pattern, reference marker RP constitutes the amplitude grating pattern, and the cycle of this amplitude grating is 1/2nd of the enlargement factor that the cycle of the phase grating of the phase grating pattern that constitutes of described test badge multiply by described projection objective PO.

Thus, be radiated on the detector DE behind the interference fringe process reference marker RP, be converted into electric signal.When there is wave aberration in projection objective PO, be introduced into a phasic difference between the two bundle coherent lights, cause position of interference fringe to be moved, when work stage ST moves, intensity according to electric signal, the position offset of interference fringe can be judged, again according to the size of side-play amount, the wave aberration of projection objective can be obtained.

Embodiment 1

Fig. 2 is the index path that mask plate MA produces vertical and inclination coherent light.As

Shown in Figure 2, mask plate MA of the present utility model comprises diffusion sheet 1, first lens 2, spatial filter 3, second lens 4 and the test badge 5 that sets gradually along optical path direction.Illuminator IL emitting laser light beam at first is radiated on the diffusion sheet 1 of mask plate MA, the main effect of diffusion sheet 1 is further homogenising laser beam, diffusion sheet 1 can be common diffusion sheet, or holographic diffusion plate, DOE (diffraction optical element), microlens array etc., light beam through diffusion sheet 1 is radiated on the test badge 5 through first lens 2, spatial filter 3 and second lens 4, first lens 2 and second lens 4 constitute a lens combination, make the light beam of incident form telecentric beam path, spatial filter 3 is arranged at the pupil plane place of lens combination.Wave filter 3 is provided with aperture, and the effect of aperture is to produce coherent light at test badge 5, and the position of aperture can also determine the angle of illuminating bundle, when aperture during at the pupil plane center, light collimated illumination, as

Shown in the A figure among Fig. 2; When aperture during not at the pupil plane center, light oblique illumination, as

Among Fig. 2 shown in the B figure.The size of aperture is set to micron order.

Test badge 5 among this embodiment 1 constitutes a plurality of phase grating patterns, and the cycle of each phase grating pattern is d.It for example is cosine distribution that the position of phase grating pattern distributes mutually ,-1 ,+1 grade of its order of diffraction time existence.Certainly, the position of phase grating pattern distributes mutually and also can be other distributions, but must make its diffraction energy mainly concentrate on-1, on+1 grade.Described a plurality of phase grating pattern is arranged at directions X and Y-direction, and the diffraction fringe of the phase grating pattern of arranging at directions X distributes at directions X, the diffraction fringe of the phase grating pattern of arranging in Y-direction distributes in Y-direction, and X, Y-direction are two orthogonal directions on the test badge plane.

Thus, the angle of diffraction of diffraction light that is radiated at 5, two orders of diffraction of test badge time of mask plate MA through the coherent light of wave filter 3 and lens combination is respectively θ ₁And θ ₂，

Fig. 3 is that the wave aberration of coherent light vertical irradiation when the phase grating pattern measured index path.As shown in Figure 3, when described coherent light vertical irradiation is on the phase grating pattern, can get according to grating equation:

dsinθ ₁＝-λ (1)

dsinθ ₂＝λ (2)

When projection objective did not have wave aberration, the electric field intensity that two bundle diffraction lights 6 and 7 are radiated on the focal plane, picture side of projection objective PO can be expressed as:

$E_1={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j---\left(3\right)$

${\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">E</figure-callout>}}_2={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j---\left(4\right)$

Wherein M is the inverse of the enlargement factor of projection objective PO, during light beam process projection objective PO, pass through b and c 2 points on the pupil plane respectively, if there is wave aberration in projection objective, light can be introduced bit phase delay during through b and c at 2, and the bit phase delay of establishing introducing is respectively φ ₂And φ ₃, at this moment, two- beam 6 and 7 electric-field intensity distribution can be expressed as:

${E_1}^{\&prime;}={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\&CenterDot;e^{j{\mathrm{\&phi;}}_2}---\left(5\right)$

${{\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">E</figure-callout>}}_2}^{\&prime;}={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\&CenterDot;e^{j{\mathrm{\&phi;}}_3}---\left(6\right)$

Two-beam interferes at place, projection objective PO focal plane, and electric field intensity is:

$E={E_1}^{\&prime;}+{{\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">E</figure-callout>}}_2}^{\&prime;}={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\&CenterDot;e^{j{\mathrm{\&phi;}}_2}+{\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">e</figure-callout>}}^j\&CenterDot;e^{j{\mathrm{\&phi;}}_3}---\left(7\right)$

With formula (1), (2) bring formula (7) into, can get:

$E=2e^{\mathrm{j\&phi;}}{e}^{i\frac{{\mathrm{\&phi;}}_3-{\mathrm{\&phi;}}_2}{2}}\cos (\frac{2\mathrm{\&pi;M}}{d}x+\frac{{\mathrm{\&phi;}}_3-{\mathrm{\&phi;}}_2}{2})---\left(8\right)$

Then light distribution is:

$I={\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">E</figure-callout>}}^2=2+2\cos (\frac{4\mathrm{\&pi;M}}{d}x+({\mathrm{\&phi;}}_3-{\mathrm{\&phi;}}_2))---\left(9\right)$

When projection objective did not have aberration, light distribution was:

$I_0=2+2\cos \left(\frac{4\mathrm{\&pi;M}}{d}x\right)---\left(10\right)$

In this embodiment, reference marker RP constitutes the amplitude grating pattern, and the cycle of this amplitude grating is 1/2nd of the enlargement factor that the cycle of the phase grating of the phase grating pattern that constitutes of described test badge multiply by described projection objective PO.

When work stage ST moves, reference marker RP is along the scanning direction of interference fringe, and when the energy of light intensity detector DE reached maximal value, the displacement that work stage ST moves was the deviation delta x of actual light intensity distribution and desirable light distribution, as shown in Figure 4, then the phasic difference of 2 of b, c is

${\mathrm{\&phi;}}_3-{\mathrm{\&phi;}}_2=-\frac{4\mathrm{\&pi;M}}{d}\mathrm{\&Delta;x}---\left(11\right)$

When on the phase grating pattern that tilts to impinge upon test badge 5 from the coherent light of mask MA outgoing with incident angle β (β＞0), as shown in Figure 5, can get according to grating equation:

dsinθ ₁+dsinβ＝-λ (12)

dsinθ ₂+dsinβ＝λ (13)

Because the angle of diffraction difference, light is selected suitable inclination angle through the position difference of projection objective, and-1 order diffraction light 6 when making+1 order diffraction light 9 and vertical irradiation overlaps, and then the position of two bundle diffracted raies introducings is respectively φ mutually ₁And φ ₂, through deriving, can obtain and the identical result of formula (11):

${\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1=-\frac{4\mathrm{\&pi;M}}{d}\mathrm{\&Delta;}{x}_1---\left(14\right)$

Therefore, by changing the incident angle of incident ray, can obtain projection objective (PO) all light beam projecting points of pupil plane (as Fig. 7. shown in) along the difference of directions X:

${\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1=-\frac{4\mathrm{\&pi;M}}{d}{\mathrm{\&Delta;x}}_1$

${\mathrm{\&phi;}}_3-{\mathrm{\&phi;}}_2=-\frac{4\mathrm{\&pi;M}}{d}{\mathrm{\&Delta;x}}_2$

${\mathrm{\&phi;}}_{n+1}-{\mathrm{\&phi;}}_n=-\frac{4\mathrm{\&pi;M}}{d}{\mathrm{\&Delta;x}}_n---\left(15\right)$

Formula (15) difference form is approximately differential form, can obtains:

$s\frac{\&PartialD;W({\mathrm{\&rho;}}_x,{\mathrm{\&rho;}}_y)}{{\&PartialD;\mathrm{\&rho;}}_x}=-\frac{4\mathrm{\&pi;M}}{d}\stackrel{\&OverBar;}{\mathrm{\&Delta;X}}---\left(16\right)$

Wherein

Be the matrix that all side-play amounts are formed, s is the distance of-1 ,+1 order of interference on pupil plane.

In like manner, use the phase grating of the beam lighting Y-direction of different directions, can obtain the equation between Y-direction wave aberration and the side-play amount:

$s\frac{\&PartialD;W({\mathrm{\&rho;}}_x,{\mathrm{\&rho;}}_y)}{{\&PartialD;\mathrm{\&rho;}}_y}=-\frac{4\mathrm{\&pi;M}}{d}\stackrel{\&OverBar;}{\mathrm{\&Delta;Y}}---\left(17\right)$

Numerical integration is carried out in formula (16), (17), can obtain projection objective wave aberration W (ρ _x, ρ _y).Should be noted that, in order to obtain whole 37 the Zernike coefficients of projection objective wave aberration, at least need 36 groups of lighting conditions (different illumination direction), therefore, need there be 36 groups of directions Xs at least in the test badge 5 of mask plate MA, the phase grating pattern of 36 groups of Y-directions, as shown in Figure 6, the light illumination mode of the corresponding different directions of each phase grating pattern, the light illumination mode of different directions is realized by the aperture position that changes on the spatial filter 3.

All light beam projecting point synoptic diagram when Fig. 7 is diffracted beam through pupil plane to the wave aberration uniform sampling on the pupil plane.Wherein stain is that diffracted beam is in the position of projection objective pupil plane.The deflection of coherent light beam is determining light in the position of pupil plane, and preferential selection can realize the coherent light beam deflection of projection objective pupil plane uniform sampling, as shown in Figure 7.Should be noted that the inhomogeneous sampling for pupil plane, can obtain the wave aberration of whole pupil plane by the method for data interpolating, but can increase the complicacy of algorithm.

Embodiment 2

The key of projection objective wave aberration pick-up unit of the present utility model is to produce two bundle coherent light beams at mask position.Utilize phase grating to realize among the embodiment 1, light beam has added the aberration at two some places when the projection objective like this, and two points can be along the pupil plane scanning sample, thereby obtains the wave aberration of whole projection objective.Illumination path at mask plate among the embodiment 1 utilizes each aperture diverse location to finish scanning sample, then adopts a kind of method of utilizing microprism array to finish change to beam direction in present embodiment 2, thereby realizes that diffracted beam is to the sampling of pupil plane.

In this embodiment 2, mask plate MA also comprises diffusion sheet 1, first lens 2, spatial filter 3, second lens 4, microprism array 11 and a plurality of test badge 12 that sets gradually along optical path direction, wherein, spatial filter 3 is arranged at the pupil plane place of the lens combination that is made of described first lens 2, second lens 4, and has aperture (not shown, with the same among the embodiment 1) on it.Test badge 12 also with embodiment 1 in test badge 5 similar, form the phase grating pattern.As different from Example 1, the stationkeeping of aperture, the partial coherence light beam of illuminator IL outgoing is converted into the coherent light 10 of vertical irradiation, as shown in Figure 8, coherent light 10 is radiated on the test badge 12 through behind the microprism array 11, and diffraction impinges upon detector DE upward (not drawing among Fig. 8) through projection objective PO after going out two bundle coherent light beams.Concrete measuring method is the same with embodiment 1.In the present embodiment, the test badge 12 of the corresponding phase grating pattern of each microprism, each prism angle θ difference above the test badge 12, the vertical like this light beam that impinges upon on the prism will produce deflection through behind the prism, and deflection angle β can be expressed as:

$\sin \mathrm{\&beta;}=(\sqrt{n^2-{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HDA00002806078300012.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2\mathrm{\&theta;}}-\cos \mathrm{\&theta;})\&CenterDot;\sin \mathrm{\&theta;}---\left(18\right)$

Wherein n is the refractive index of prism, and when the prism angle was smaller, deflection angle β can be expressed as:

β＝(n-1)θ (19)

Wherein deflection angle determines the position of light on pupil plane, utilize formula (18) or (19) can obtain the inclination angle of prism, should be noted that, the microprism of microprism array 11 can also can stick together with the phase grating pattern of test badge 12 on phase grating 12 patterns of test badge 12.In order to eliminate microprism angle mismachining tolerance to the influence of measuring accuracy, should measure the physical location of light on pupil plane through microprism before the test, the error that calibration one by one causes because of the prism inclination angle.

In this embodiment 2, use be the deflection that refracting prisms are finished light beam, but the utility model is not limited thereto, and also can use catoptron to realize, perhaps uses dynamically the pendulum mirror to finish light deflection.

Utilize the coherent light illumination phase grating in the utility model, and the diffracted ray of phase grating only exists-1 ,+1 grade, therefore, it is just relevant through the aberration of two some positions of pupil plane with diffraction grating to influence grating interference image position side-play amount, and use partial coherence to throw light on and the multistage interference of light in prior art 1 and the prior art 2, light is a face through the zone of pupil plane, and all aberrations all influence the position of grating picture in the face.Compared to existing technology 1 and prior art 22, the utility model not only can be measured whole 37 Zernike coefficients, and measuring method is simple, the measuring accuracy height.

Above-described specific embodiment; the purpose of this utility model, technical scheme and beneficial effect are further described; be understood that; the above only is specific embodiment of the utility model; be not limited to the utility model; all within spirit of the present utility model and principle, any modification of making, be equal to replacement, improvement etc., all should be included within the protection domain of the present utility model.

Claims (9)

1. an on-line detection device of wave aberration of projection lens comprises light source (LA), projection objective (PO), reference marker (RP) and detector (DE), and described light source (LA) is used for shoot laser, it is characterized in that:

Described device also comprises mask plate (MA), incides described projection objective (PO) by described light source (LA) emitting laser after via this mask plate (MA);

Described mask plate (MA) comprises the test badge that is used to form interference fringe, and test badge constitutes the phase grating pattern;

Described reference marker (RP) is arranged on the place, focal plane of described projection objective (PO), constitutes the amplitude grating pattern;

Described detector (DE) is arranged on the rear of reference marker in the described light path (RP);

Wherein, described mask plate (MA) can will be converted to two bundle coherent lights by described light source (LA) emitting laser, and this two bundles coherent light place, focal plane at described projection objective (PO) behind described projection objective (PO) interferes, and produces interference fringe; Be radiated on the described detector (DE) behind this interference fringe described reference marker of process (RP).

2. on-line detection device of wave aberration of projection lens as claimed in claim 1 is characterized in that: the cycle of the amplitude grating of described amplitude grating pattern is 1/2nd of the enlargement factor that the cycle of the phase grating of the phase grating pattern that constitutes of described test badge multiply by described projection objective (PO).

3. on-line detection device of wave aberration of projection lens as claimed in claim 1 is characterized in that:

Described mask plate (MA) comprises first lens (2), spatial filter (3), second lens (4) and the test badge (5) that sets gradually along optical path direction, wherein,

Described spatial filter (3) is arranged at the pupil plane place of the lens combination that is made of described first lens (2), second lens (4), and has aperture on it, and this aperture is used for described laser is converted into coherent light;

Described test badge (5) comprises a plurality of phase grating patterns that Y-direction is arranged on directions X, and the diffraction fringe of the phase grating pattern of arranging at directions X distributes at directions X, the diffraction fringe of the phase grating pattern of arranging in Y-direction distributes in Y-direction, and the diffraction energy of each phase grating pattern concentrates on-1, on+1 grade, described X, Y-direction is two orthogonal directions on the test badge plane, the light illumination mode of the corresponding different directions of each phase grating pattern, the light illumination mode of different directions is realized by the aperture position that changes on the described spatial filter 3.

4. on-line detection device of wave aberration of projection lens as claimed in claim 3, it is characterized in that: described mask plate (MA) also comprises diffusion sheet (1), it is arranged at the place ahead of first lens described in the light path (2).

5. on-line detection device of wave aberration of projection lens as claimed in claim 3, it is characterized in that: described test badge 5 comprises 36 groups of directions Xs at least, the phase grating pattern of 36 groups of Y-directions.

6. on-line detection device of wave aberration of projection lens as claimed in claim 5 is characterized in that: the relevant direction of light of described two bundles is chosen as the direction that the pupil plane that makes described projection objective (PO) can uniform sampling.

7. on-line detection device of wave aberration of projection lens as claimed in claim 1, it is characterized in that: described mask plate (MA) comprises first lens (2), spatial filter (3), second lens (4), light beam deviation element arrays (11) and a plurality of phase grating (12) that sets gradually along optical path direction, wherein

Described spatial filter (3) is arranged at the pupil plane place of the lens combination that is made of described first lens (2), second lens (4), and has aperture on it, the stationkeeping of this aperture, be used for described laser is converted into the coherent light of vertical outgoing, be radiated on the described phase grating (12) behind the described coherent light described light beam deviation element arrays of process (11), diffraction goes out two bundle coherent light beams.

8. described on-line detection device of wave aberration of projection lens as claimed in claim 7, it is characterized in that: described light beam deviation element arrays (11) comprises a plurality of light beam deviation elements, the corresponding phase grating (12) of each light beam deviation element, and each light beam deviation element is to the deflection angle difference of light beam.

9. described on-line detection device of wave aberration of projection lens as claimed in claim 8 is characterized in that: described light beam deviation element arrays (11) is for refracting prisms, catoptron or dynamically put mirror.

Images