CN100492180C - Projection objective detecting method - Google Patents

Projection objective detecting method Download PDF

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CN100492180C
CN100492180C CNB2007100436241A CN200710043624A CN100492180C CN 100492180 C CN100492180 C CN 100492180C CN B2007100436241 A CNB2007100436241 A CN B2007100436241A CN 200710043624 A CN200710043624 A CN 200710043624A CN 100492180 C CN100492180 C CN 100492180C
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projection objective
polarization spectroscope
wave
wavefront
detection
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CN101082777A (en
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刘国淦
段立峰
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Shanghai Micro Electronics Equipment Co Ltd
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Abstract

The invention discloses a detecting method of projective object lens of photo-etching machine, which comprises the following steps: (a1) moving working platform to the set position; (a2) sending illuminating order to the light source; separating the light source into measuring wave front and reference wave front to project on the optical detecting element separately through optical path separator; (a3) receiving the gathered image information through optical detecting element; (a4) calculating the image information to obtain true phase information; (a5) reducing the phase information into wave front error information; (a6) judging the position of the wave front to display the character of wave front according to the error information of the wave front. The invention can measure the wave front error, magnification ratio, distortion and field curvature of objective lens precisely, which reduces the size of optical detecting element with simple preparation, high precision and convenient operation.

Description

The method that projection objective detects
Technical field
The present invention relates to the method that a kind of projection objective detects, particularly the method for the detection of the projection lens of lithography machine in microdevice manufacturing process such as semiconductor element, liquid crystal display cells.
Background technology
In recent years, in the semiconductor lithography field, the projection lithography continuous advancement in technology, lines advance to meticulousr direction, and the current chip critical size can reach the photoetching resolution characteristic of 90nm~65nm.The image quality of the optical projection object lens in the etching system is the key factors that influence photolithography resolution.Projection objective can reach very high quality when design, but all can influence the optical quality of object lens in the process of processing, debuging and transport at optics, this guarantees that with regard to the optical detecting method that needs off-line object lens have image quality preferably when working in the working site; Even very high precision is arrived in Installation and Debugging in the working site in addition, but environmental change thereupon, or exposure all can cause the change of quality of optical imaging to the radiation effect of glass material, the detection system that this just needs an online objective lens image quality of energy to change.
At present the projection objective detection system has a variety of methods, the off-line checking method that PMI interferometer that adopts as Zeiss company or the company that has adopt Hartmann method etc. to carry out.Also designed the online test method that a kind of Hartmann of use method is carried out just like Nikon company, shown in U.S. Pat 6975387, this online test method adopts the laser instrument of extraneous frequency multiplication, produce continuous light source, shine on the mask of mask platform through illuminator, when measuring the image quality of projection objective, a pin hole that is used to produce the standard ball ground roll is arranged on the mask, this standard ball ground roll focuses on the work stage through behind the tested projection objective, there is a Hartmann detector on the work stage next door, before this detector can be converted to parallel wave with the standard ball ground roll, and the process lens arra converges on the ccd image sensor (CCD).In the image quality of measuring projection objective, when if there is aberration in projection objective, this aberration will be reflected on the plane wave front of process Hartmann sensor back, the position of the convergent point behind the process lens arra by more satisfactory plane wave and imperfect plane wave, the wavefront slope that just can obtain a non-standard plane wave changes, by the wavefront slope of measurement plane ripple, derive the wavefront error of plane wave.But the major defect of this online objective lens method is: 1. need to introduce extra light source and measure; 2. using the Hartmann sensor is that wavefront is carried out sampling Detection, because the restriction of making, Hartmann spatial sampling rate can not be too high, so the senior aberration of energy measurement projection objective not.3.CCD make strictly,,, will inevitably cause the site error of central point like this if itself there is scale error in the CCD manufacturing because the precision of Hartmann sensor directly determined by the spot center on the CCD.4. the manufacturing difficulty of array lens, the optical parallax that its is introduced influences the bearing accuracy of spot.5. in addition for measuring accuracy, also need to improve the focal length of array lens, also can bring the size of Hartmann sensor and CCD to become big so simultaneously.6. the algorithm complexity determined of the position of spot, its model are influenced by more multifactor aberration as CCD characteristic array lens etc. and are difficult to determine.In addition, in U.S. Pat 6573997, described a kind of grating that utilizes and realized that the phase shift point diffraction interference comes the method for objective lens, this method can effectively be measured the objective lens aberration situation near diffraction limit, but it need use two gratings to realize beam split, preparing grating is all very difficult with assembling, be not suitable on litho machine integratedly, this in addition method is to realize phase shift at one time, so need accurately control light source.
For the precision that improves the online detection of object lens satisfying higher optical patterning requirement, the present invention propose a kind of accurately, the detection method of projection lens of lithography machine easily.
Summary of the invention
The object of the present invention is to provide a kind of detection method of projection lens of lithography machine, this detection method is the accuracy of detection height not only, and makes simple and easy to operate.
In order to reach described purpose, the invention provides the method that a kind of projection objective detects, wherein, described detection method comprises the following steps: that (a1) is divided into two bundles with the light beam that light source penetrates, a branch of preceding inlet of reference light wave that projects the aberration detection system, another bundle becomes the standard wave anteroposterior diameter and crosses the measuring light wavefront inlet that the projection objective imaging optical path projects the aberration detection system through the pin hole on the mask; (a2) mobile aberration detection system is to assigned address, and wherein this assigned address scans the scanning position of above-mentioned pin hole for the aberration detection system; (a3) the aberration detection system receives the image information that collects; (a4) above-mentioned image information is carried out computing and obtain phase shift information; (a5) above-mentioned phase shift information is reduced to the wavefront error information of projection objective;
In the method that above-mentioned projection objective detects, further comprising the steps of afterwards in described step (5): (a6) according to above-mentioned wavefront error information, whether the wavefront of judging this moment is in the optimum position, if wavefront is to be in the optimum position, the feature of carrying out wavefront shows; If wavefront is not to be in the optimum position, then get back to step (a2), continue execution in step (a2) to step (a6) and be in the optimum position up to wavefront.
In the method that above-mentioned projection objective detects, described aberration detection system is interferometer and is assemblied on the work stage, and described work stage can and vertically accurately be located in level.
In the method that above-mentioned projection objective detects, described interferometer comprises first polarization spectroscope, being positioned at being respectively applied for of the first polarization spectroscope incidence surface, one side introduces before the reference light wave and two collimation lens set of measuring light wavefront, be positioned at second, third polarization spectroscope of the first polarization spectroscope exiting surface, one side, dispose 1/2nd wave plates and quarter-wave plate between first polarization spectroscope and the 3rd polarization spectroscope, dispose quarter-wave plate between first polarization spectroscope and second polarization spectroscope.
In the method that above-mentioned projection objective detects, described collimation lens enters polarization spectroscope after making the spherical wave of incident become plane wave.
In the method that above-mentioned projection objective detects, dispose ccd image sensor on the exiting surface of described second, third polarization spectroscope.
In the method that above-mentioned projection objective detects, optical range is identical between described collimation lens set and the ccd image sensor.
In the method that above-mentioned projection objective detects, the surface of described first, second, third polarization spectroscope, 1/2nd wave plates, quarter-wave plate and ccd image sensor is the plane.
In the method that above-mentioned projection objective detects, described image information is the light intensity value that ccd image sensor receives, and wherein the light intensity value that the ccd image sensor at the exiting surface place vertical with its incidence surface receives on second polarization spectroscope is I 1The light intensity value that the ccd image sensor at the exiting surface place parallel with its incidence surface receives on second polarization spectroscope is I 2The light intensity value that the ccd image sensor at the exiting surface place vertical with its incidence surface receives on the 3rd polarization spectroscope is I 3The light intensity value that the ccd image sensor at the exiting surface place parallel with its incidence surface receives on the 3rd polarization spectroscope is I 4
In the method that above-mentioned projection objective detects, the wavefront error of described projection objective
Figure C200710043624D0007083143QIETU
Calculate by following formula:
φ ( x , y ) = arctg ( I 4 ( x , y ) - I 2 ( x , y ) I 1 ( x , y ) - I 3 ( x , y ) ) .
In the method that above-mentioned projection objective detects, described step (a1) also comprises step before: (b0) at the mask of mask platform carrier tape pinhole array; Described step (a5) also comprises step afterwards: (b6) control information before the marking wave; (b7) vertical moving after the described aberration detection system, repeating step (a2) is to step (b6); (b8) determine wavefront error a hour corresponding vertical position be that the best is practised physiognomy.
In the method that above-mentioned projection objective detects, described step (b8) also comprises step afterwards: (b9) scan all pin holes of mask face, and measure the image planes position of different hole points on the mask; (b10) the best image point position and the physical location of pin hole on mask plate of all pin holes of comparison pinhole mask; (b11) magnification or the distortion or the curvature of field of calculating projection objective.
In the method that above-mentioned projection objective detects, the magnification of described calculating projection objective or the method for distortion get a curve for optimum position deviation and the position of pin hole on mask plate by more described all pin holes of pinhole mask, wherein linear segment is the magnification deviation of projection objective, and non-linear partial is the distortion of projection objective.
In the method that above-mentioned projection objective detects, the vertical described projection objective vertical moving of described aberration detection system, the upright position of measuring different field positions calculates the curvature of field of projection objective.
In the detection method of above-mentioned projection objective, described aberration detection system is interferometer and is assemblied on the work stage that described work stage can accurately be located with vertical direction in the horizontal direction.
In the method that above-mentioned projection objective detects, described interferometer comprises first polarization spectroscope, being positioned at being respectively applied for of the first polarization spectroscope incidence surface, one side introduces before the reference light wave and two collimation lens set of measuring light wavefront, be positioned at second, third polarization spectroscope of the first polarization spectroscope exiting surface, one side, dispose 1/2nd wave plates and quarter-wave plate between first polarization spectroscope and the 3rd polarization spectroscope, dispose quarter-wave plate between first polarization spectroscope and second polarization spectroscope.
In the method that above-mentioned projection objective detects, described collimation lens set is a condenser lens.
In the method that above-mentioned projection objective detects, dispose ccd image sensor on the exiting surface of described second, third polarization spectroscope.
In the method that above-mentioned projection objective detects, optical range is identical between described collimation lens set and the ccd image sensor.
In the method that above-mentioned projection objective detects, the surface of described first, second, third polarization spectroscope, 1/2nd wave plates, quarter-wave plate and ccd image sensor is the plane.
The present invention makes it compared with prior art owing to adopted above-mentioned technical scheme, has following advantage and good effect:
1. the wavefront space employing rate of optical system can be significantly improved, the details of more wavefront medium-high frequency can be reflected;
2. the present invention has the advantage of PMI (phase-shift measurement interferometer) interferometer, does not need standard reference lens simultaneously, but realizes the standard spherical wave front by aperture;
3. the present invention does not need LASER Light Source that good coherence is arranged, and can directly use existing laser pulse light source.
4. detection method of the present invention reduces the size linearity and the noise requirements of CCD, thereby can improve the wavefront error susceptibility and the accuracy of detection of wavefront system greatly.
Description of drawings
To the description of one embodiment of the invention, can further understand purpose, specific structural features and the advantage of its invention by following in conjunction with its accompanying drawing.Wherein, accompanying drawing is:
Fig. 1 is the structural representation of projection objective pick-up unit of the present invention;
Fig. 2 is the inner structure synoptic diagram of the interferometer in the projection objective pick-up unit of Fig. 1;
Fig. 3 is the process flow diagram of a kind of projection objective detection method of the present invention;
Fig. 4 is the process flow diagram of another kind of projection objective detection method of the present invention.
Embodiment
Below will be described in further detail projection objective detection method of the present invention.
Object lens pick-up unit of the present invention is on the basis of existing litho machine work stage and Laser Transmission light path to be transformed, adopt reference light and measuring light to carry out relevant method of moment, eliminate the influence of the fluctuation of measurement light source, realize the online detection of projection objective optical measurement.Concrete device is as follows:
At first see also Fig. 1, Fig. 1 is the overall construction drawing of the projection objective detection system of one embodiment of the present of invention.After the light source 9 of litho machine passes through bottom module, transmission light path 10 and illuminator 1, shine on the mask 2, be imaged on the silicon chip face 11 by projection objective 4 then.Measuring light of the present invention is also transmitted by such light path, and what place on mask platform 3 is pinhole mask version 2, produces the standard spherical wave front, uses optical detection elements such as interferometer 6 to receive on the image planes of object lens.
Interferometer 6 is assemblied on the angle of work stage 5, it can be moved on to the optional position of the visual field of projection objective 4 by work stage 5, the concrete structure of interferometer 6 as shown in Figure 2, the focus of interferometer convergent lens 23b is exactly image planes 21 positions of object lens, the reference light source of interferometer 6 is introduced by light path resolution element in the Laser Transmission light path 10 such as spectroscope 8, before the light wave that spectroscope 8 beam split are come out, be coupled to the optical fiber 12, be transferred to together in the interferometer 6 on the work stage by optical fiber 12 and other cable before the above-mentioned light wave.High-quality in order to produce with reference to spherical wave front, the light of optical fiber outgoing place is coupled in the pin hole flat board 22 again, the orifice size of pin hole flat board 22 is got the Airy disk size of diffraction limit, just can obtain high-quality spherical wave front like this after small holes.
Before the measurement wavefront and reference light wave through projection objective 4 outgoing, reference light and measuring light are coherent light, after entering the measurement wavefront inlet and the preceding inlet of reference light wave of interferometer 6 respectively, at first all through two collimation lens set 23a, 23b, collimation lens set 23a, 23b are condenser lens, and condenser lens 23a, 23b enter first polarization spectroscope 24 after making the spherical wave of incident become plane wave.Be divided into the mutually perpendicular S light in polarization direction (polarization direction and the vertical light of the plane of incidence) and P light (light that the polarization direction is parallel with the plane of incidence) from the light of polarization spectroscope 24 outgoing.Because reference light and measuring light are from the both direction incident of polarization spectroscope, so all comprise S light and P light through the two-beam of polarization spectroscope.
Interferometer 6 comprises first polarization spectroscope 24, being positioned at being respectively applied for of first polarization spectroscope, 24 incidence surfaces, one side introduces before the reference light wave and two condenser lens 23a of measuring light wavefront, 23b, be positioned at second polarization spectroscope 25 of first polarization spectroscope, 24 exiting surfaces, one side, the 3rd polarization spectroscope 28, dispose 1/2nd wave plates 26 and quarter-wave plate 27a between first polarization spectroscope 24 and the 3rd polarization spectroscope 28, configuration quarter-wave plate 27b between first polarization spectroscope 24 and second polarization spectroscope 25, and second spectroscope 25, four ccd image sensor 29a of configuration on the exiting surface of the 3rd polarization spectroscope 28,29b, 29c, 29d.Wherein, the quarter-wave plate 27a of configuration is near the 3rd polarization spectroscope 28 between first polarization spectroscope 24 and the 3rd polarization spectroscope 28, described 1/2nds wave plates are near first polarization spectroscope 24, and the surface of first polarization spectroscope 24, second polarization spectroscope 25, the 3rd polarization spectroscope 28,1/2nd wave plates 26, quarter- wave plate 27a, 27b and ccd image sensor 29a, 29b, 29c, 29d is the plane.Optical range is identical between collimation lens set 23a, 23b and four ccd image sensor 29a, 29b, 29c, the 29d, and four ccd image sensor 29a, 29b, 29c, 29d image data simultaneously.
The S light of reference light and the P light of measuring light, from the 24 following outgoing of first polarization spectroscope, 90 degree phase shifts will all be introduced through a quarter-wave plate 27b between two kinds of polarized lights earlier, if originally reference light and by between the photometry the position be X and Y mutually, behind this quarter-wave plate 27b, because the polarization direction between them is vertical, the optical axis of quarter-wave plate 27b and these two polarization directions all are 45 degree, so behind quarter-wave plate 27b (the branch optical axis is consistent with quarter-wave plate), their phase change is: reference light partly becomes X and X+45 degree; Measuring light partly becomes Y and Y-45 degree (not considering the phase shift of common road part).Through behind the second following polarization spectroscope 25, S and P light enter two CCD29c and 29d respectively, and the phase shift between them is respectively X-Y and X-Y+90 degree.
And the S light of the P light of reference light and measuring light, from the 24 the right outgoing of first polarization spectroscope, earlier will all introduce the half-wavelength phase shift between two kinds of polarized lights through one 1/2nd wave plate 26 (slow-axis direction and always) with reference to direction of light, position between the orthogonal polarized light of such two bundles becomes X+180 and Y mutually, after this two-beam passes through this quarter-wave plate 27a again (optical axis becomes 45 degree with two polarized lights), the position of two-beam becomes X+180 and X+180+45 mutually respectively; Y and Y-45 degree; Again through behind the 3rd polarization spectroscope 28 of back (divide optical axis consistent), resolve into S light and P light enters 29b and 29a respectively with quarter-wave plate.Phase shift between them is respectively X-Y+180 and X-Y+270 degree;
Obtaining reference light and the phase shift between the measuring light that four CCD receive from last analysis is respectively X-Y, X-Y-90, X-Y-180, X-Y+270 degree.Four width of cloth images that utilize these four CCD to gather just can calculate wavefront, and relevant with reference to corrugated and tested corrugated, the light distribution of interference field can be expressed as:
I(x,y,t)=I d(x,y)+I a(x,y)cos[φ(x,y)-δ(t)] (2-1)
In the formula, I d(x y) is the direct current light distribution of interference field;
I a(x y) is the interchange light distribution of interference field;
φ (x, y) be tested corrugated and phase differential with reference to the corrugated distributes, i.e. the measuring object of PMI;
δ (t) is the variable phase in two optical interference circuits.
Change phase place δ (t) by top method, measure light distribution I in the interferogram of four width of cloth phase change (x, y, t), and to φ (x y) accurately finds the solution.
Formula (2-1) can be rewritten as:
I(x,y,δ i)=a 0(x,y)+a 1(x,y)cosδ i+a 2(x,y)sinδ i
A in the formula 0(x, y)=I d(x, y)
a 1(x,y)=I a(x,y)cos[φ(x,y)]
a 2(x,y)=-I a(x,y)sin[φ(x,y)]
(x y) can pass through a to tested phase 2(x, y) and a 1(x, ratio y) is tried to achieve:
φ ( x , y ) = arctg ( a 2 ( x , y ) a 1 ( x , y ) )
For four step phase shift: δ of the present invention 1=0, δ 2=pi/2, δ 3=π, δ 4=3 pi/2s, bring above formula into and obtain:
φ ( x , y ) = arctg ( I 4 ( x , y ) - I 2 ( x , y ) I 1 ( x , y ) - I 3 ( x , y ) )
I in the following formula 1, I 2, I 3, I 4Distinguish the light intensity value in four width of cloth images, obtain the phase value of each point of wavefront like this by four light intensity values of each pixel location, preferably by fitting the phase value that obtains whole wavefront.
Interferometer of the present invention can also be used to the NA (NA represents the numerical aperture of projection lens of lithography machine) of direct objective lens and the light distribution of illumination iris except the imaging with above-mentioned measurement object lens.Measuring method is as follows: by the image that receives on any one CCD that analyzes interferometer; The focal length of supposing the condenser lens of interferometer is f, if the size of the circular light spot that receives on CCD is D, the NA of object lens is sin (atan (D/ (2f))) so.Analyze the coherence of object lens illumination and the characteristic of off-axis illumination (two utmost points, four utmost points, annular) according to the feature of the concrete image that receives on the CCD in addition.The present invention is owing to adopt polarization spectroscope, and it is the polarization information of the wavefront of objective lens easily.When the NA of object lens is big, owing to, can cause bigger Polarization Dependent Loss in the incident angle difference of lens surface.Can accurately measure these polarization informations by interferometer of the present invention.Provide more fully information for analyzing image quality.
Fig. 3 is the process flow diagram of a kind of object lens detection method of the present invention, is the process flow diagram of objective lens aberration specifically.As shown in Figure 3, at first open work stage, work stage is moved on to appointed positions, send instruction for then the light source of litho machine and throw light on, interferometer is accepted four images that CCD collects simultaneously, the more relevant method calculation process of four width of cloth imagery exploitations is obtained real phase shift information, and be wavefront error information by four width of cloth phase shift information image restorings, whether the wavefront of judging this moment at last is in the optimum position, if wavefront is to be in the optimum position, the feature of carrying out wavefront shows; If wavefront is not to be in the optimum position, then get back to the step that worktable is moved on to appointed positions, and the above step of continuation execution is in the optimum position up to wavefront.
Fig. 4 is the process flow diagram of another kind of object lens detection method of the present invention, is the process flow diagram of objective lens distortion and magnification specifically.This method is to place the mask that has pinhole array on mask platform, the travelling workpiece platform allows the work stage band interferometer at these apertures of best image plane scanning, when the imaging wavefront is best in quality, write down the real standard position of work stage, represent the position of the picture of this point on the mask.Repeat above-mentioned steps and be scanned end up to all pin holes.By measuring the image planes position of the point in different holes on the mask, then by comparing these image planes position deviations and their physical locations on mask, they are fitted obtain a curve, linear segment is the magnification deviation of object lens, and non-linear partial can be regarded as the distortion of object lens.
When measuring magnification and distortion, if work stage tilts, the shape of stripes that receives on the interferometer can not change, and this is that same inclination also takes place reference light source because when work stage tilts, and this two goes on foot branch and be tilted in and be cancelled relevant the time.And if picture point is when moving in the horizontal direction, the striped on inclination corrugated just can appear in the striped of interferometer at once.The focal length of supposing condenser lens is f, and the diameter of CCD epigraph is D, and the fringe number of appearance is n, and wavelength is λ, and the size of transversal displacement d is about n * λ * f/D so; So can directly infer the horizontal level of picture point, thereby can get rid of the influence of the inclination of work stage by the variation of striped.
In like manner, the present invention utilizes the object lens detection method of Fig. 4 can also be used for measuring the position of best image planes and the information of the curvature of field.When interferometer carries out vertical move under the control of vertical measuring equipment (7 among Fig. 1), the position of finding the wavefront error minimum is exactly the position of best image planes.And just can obtain the information of the object lens curvature of field by the vertical position of measuring different field positions.
Light source as optical detecting method of the present invention and device can be continuously or pulsed light, do not need special extraneous measuring light to realize the continuous coverage light source, and because the length of optical fiber can be regulated, and four light path basically identicals that CCD receives, so light source can not need good coherence, the light source that it can be deep ultraviolet wavelength or other wave band detects.
Adopt object lens detection method of the present invention and device, can significantly improve the wavefront space employing rate of optical system, can reflect the details of more wavefront medium-high frequency, and have the advantage of PMI interferometer, do not need simultaneously standard reference lens, but realize the standard spherical wave front by aperture; In addition, detection method of the present invention reduces the size linearity and the noise requirements of CCD, thereby can improve the wavefront error susceptibility and the accuracy of detection of wavefront system greatly.
That more than introduces only is based on preferred embodiment one by one of the present invention, can not limit scope of the present invention with this.Any method of the present invention is done replacement, the combination, discrete of step well know in the art, and the invention process step is done well know in the art being equal to change or replace and all do not exceed exposure of the present invention and protection domain.

Claims (20)

1, a kind of method of projection objective detection is characterized in that described detection method comprises the following steps:
(a1) light beam that light source is penetrated is divided into two bundles, a branch of preceding inlet of reference light wave that projects the aberration detection system, another bundle becomes the standard wave anteroposterior diameter and crosses the measuring light wavefront inlet that the projection objective imaging optical path projects the aberration detection system through the pin hole on the mask;
(a2) mobile aberration detection system is to assigned address, and wherein this assigned address scans the scanning position of above-mentioned pin hole for the aberration detection system;
(a3) the aberration detection system receives the image information that collects;
(a4) above-mentioned image information is carried out computing and obtain phase shift information;
(a5) above-mentioned phase shift information is reduced to the wavefront error information of projection objective;
2, the method for projection objective detection as claimed in claim 1, it is characterized in that: (a5) is further comprising the steps of afterwards in described step:
(a6) according to above-mentioned wavefront error information, judge whether the wavefront of this moment is in the optimum position, if wavefront is to be in the optimum position, the feature of carrying out wavefront shows; If wavefront is not to be in the optimum position, then get back to step (a2), continue execution in step (a2) to step (a6) and be in the optimum position up to wavefront.
3, the method that detects of projection objective as claimed in claim 1 or 2 is characterized in that: described aberration detection system is interferometer and is assemblied on the work stage, and described work stage can and vertically accurately be located in level.
4, the method for projection objective detection as claimed in claim 3, it is characterized in that: described interferometer comprises first polarization spectroscope, being positioned at being respectively applied for of the first polarization spectroscope incidence surface, one side introduces before the reference light wave and two collimation lens set of measuring light wavefront, be positioned at second, third polarization spectroscope of the first polarization spectroscope exiting surface, one side, dispose 1/2nd wave plates and quarter-wave plate between first polarization spectroscope and the 3rd polarization spectroscope, dispose quarter-wave plate between first polarization spectroscope and second polarization spectroscope.
5, the method for projection objective detection as claimed in claim 4, it is characterized in that: described collimation lens enters polarization spectroscope after making the spherical wave of incident become plane wave.
6, the method for projection objective detection as claimed in claim 4, it is characterized in that: dispose four imageing sensors on the exiting surface of described second, third polarization spectroscope, wherein said imageing sensor lays respectively on two exiting surfaces of two exiting surfaces of second polarization spectroscope and the 3rd polarization spectroscope.
7, the method that detects of projection objective as claimed in claim 6 is characterized in that: described first collimation lens set, second collimation lens set are identical with optical range between four ccd image sensors.
8, the method for projection objective detection as claimed in claim 6, it is characterized in that: the surface of described first, second, third polarization spectroscope, 1/2nd wave plates, quarter-wave plate and ccd image sensor is the plane.
9, the method for projection objective detection as claimed in claim 6, it is characterized in that: described image information is the light intensity value that ccd image sensor receives, and wherein the light intensity value that the ccd image sensor at the exiting surface place vertical with its incidence surface receives on second polarization spectroscope is I 1The light intensity value that the ccd image sensor at the exiting surface place parallel with its incidence surface receives on second polarization spectroscope is I 2The light intensity value that the ccd image sensor at the exiting surface place vertical with its incidence surface receives on the 3rd polarization spectroscope is I 3The light intensity value that the ccd image sensor at the exiting surface place parallel with its incidence surface receives on the 3rd polarization spectroscope is I 4
10, the method for projection objective detection as claimed in claim 9 is characterized in that: the wavefront error of described projection objective Calculate by following formula:
φ ( x , y ) = arctg ( I 4 ( x , y ) - I 2 ( x , y ) I 1 ( x , y ) - I 3 ( x , y ) ) .
11, the method for projection objective detection as claimed in claim 1 is characterized in that:
Described step (a1) also comprises step before:
(b0) at the mask of mask platform carrier tape pinhole array;
Described step (a5) also comprises step afterwards:
(b6) control information before the marking wave;
(b7) vertical moving after the described aberration detection system, repeating step (a2) is to step (b6);
(b8) determine wavefront error a hour corresponding vertical position be that the best is practised physiognomy.
12, the method for projection objective detection as claimed in claim 11 is characterized in that:
Described step (b8) also comprises step afterwards:
(b9) scan all pin holes of mask face, and measure the image planes position of different hole points on the mask;
(b10) the best image point position and the physical location of pin hole on mask plate of all pin holes of comparison pinhole mask;
(b11) magnification or the distortion or the curvature of field of calculating projection objective.
13, the method for projection objective detection as claimed in claim 12, it is characterized in that: the magnification of described calculating projection objective or the method for distortion get a curve for optimum position deviation and the position of pin hole on mask plate by more described all pin holes of pinhole mask, wherein linear segment is the magnification deviation of projection objective, and non-linear partial is the distortion of projection objective.
14, the method for projection objective detection as claimed in claim 13, it is characterized in that: the vertical described projection objective vertical moving of described aberration detection system, the upright position of measuring different field positions calculates the curvature of field of projection objective.
15, as the method for claim 11 or 12 or 13 or 14 described projection objectives detections, it is characterized in that: described aberration detection system is interferometer and is assemblied on the work stage that described work stage can accurately be located with vertical direction in the horizontal direction.
16, the method for projection objective detection as claimed in claim 15, it is characterized in that: described interferometer comprises first polarization spectroscope, being positioned at being respectively applied for of the first polarization spectroscope incidence surface, one side introduces before the reference light wave and two collimation lens set of measuring light wavefront, be positioned at second, third polarization spectroscope of the first polarization spectroscope exiting surface, one side, dispose 1/2nd wave plates and quarter-wave plate between first polarization spectroscope and the 3rd polarization spectroscope, dispose quarter-wave plate between first polarization spectroscope and second polarization spectroscope.
17, the method for projection objective detection as claimed in claim 16, it is characterized in that: described collimation lens set is a condenser lens.
18, the method for projection objective detection as claimed in claim 16, it is characterized in that: dispose four imageing sensors on the exiting surface of described second, third polarization spectroscope, wherein said imageing sensor lays respectively on two exiting surfaces of two exiting surfaces of second polarization spectroscope and the 3rd polarization spectroscope.
19, the method that detects of projection objective as claimed in claim 18 is characterized in that: described first collimation lens set, second collimation lens set are identical with optical range between four ccd image sensors.
20, the method for projection objective detection as claimed in claim 18, it is characterized in that: the surface of described first, second, third polarization spectroscope, 1/2nd wave plates, quarter-wave plate and ccd image sensor is the plane.
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CN102073217B (en) * 2009-11-20 2012-06-20 上海微电子装备有限公司 Real-time measuring device and method for wave aberration
CN101799633B (en) * 2010-03-15 2011-12-21 上海微电子装备有限公司 Method and device for off-line measurement of optimal object plane of imaging system
CN102375329B (en) * 2010-08-20 2013-04-10 上海微电子装备有限公司 Test mask and method for measuring exposure system parameters therewith
CN103091993B (en) * 2011-11-02 2015-02-11 上海微电子装备有限公司 Test mark and measuring method used in lithography machine lens thermal effect measuring
CN103324036A (en) * 2013-07-04 2013-09-25 中国科学院光电技术研究所 Device and method for detecting ratio and distortion of projection objective
CN104865799B (en) * 2015-05-14 2017-06-27 中国科学院光电技术研究所 A kind of photoetching projection objective lens polarize simulating analysis
CN110686871B (en) * 2019-05-20 2021-08-27 苏州大学 Numerical aperture measuring device and method of self-focusing lens

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