CN108803248B - On-line detection device and method for numerical aperture of projection objective - Google Patents
On-line detection device and method for numerical aperture of projection objective Download PDFInfo
- Publication number
- CN108803248B CN108803248B CN201810416484.6A CN201810416484A CN108803248B CN 108803248 B CN108803248 B CN 108803248B CN 201810416484 A CN201810416484 A CN 201810416484A CN 108803248 B CN108803248 B CN 108803248B
- Authority
- CN
- China
- Prior art keywords
- numerical aperture
- projection
- projection objective
- detector
- line detection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 55
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000005259 measurement Methods 0.000 claims abstract description 28
- 239000000758 substrate Substances 0.000 claims description 47
- 239000010453 quartz Substances 0.000 claims description 44
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 44
- 238000001459 lithography Methods 0.000 claims description 20
- 239000011148 porous material Substances 0.000 claims description 13
- 238000005286 illumination Methods 0.000 claims description 12
- 238000003384 imaging method Methods 0.000 claims description 11
- 239000002184 metal Substances 0.000 claims description 9
- 239000000047 product Substances 0.000 claims description 4
- 239000012467 final product Substances 0.000 claims description 3
- 238000001259 photo etching Methods 0.000 abstract description 10
- 238000011065 in-situ storage Methods 0.000 abstract description 7
- 238000009434 installation Methods 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000000306 component Substances 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
- G03F7/7085—Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/02—Testing optical properties
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
- G03F7/70591—Testing optical components
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Epidemiology (AREA)
- Public Health (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to the technical field of detection of performance parameters of a photoetching machine, in particular to an on-line detection device and method for numerical aperture of a projection objective. The invention aims to solve the technical problem that numerical apertures detected by projection objective before and after installation are different. For this purpose, the invention provides an on-line detection device for the numerical aperture of a projection objective, comprising a scattering element which can be arranged on a mask table, a numerical aperture measurement device which can be arranged on a workpiece table, the scattered light beam of a light source passing through the scattering element covering the projection objective and being projected by the projection objective onto the numerical aperture measurement device, the numerical aperture measurement device being able to detect the numerical aperture of the projection objective from the projection beam of the scattered light beam onto the numerical aperture measurement device. The on-line detection device can perform in-situ on-line and rapid measurement on the numerical aperture of the projection objective after the installation is completed, so that the accuracy of the numerical aperture detection of the projection objective is improved.
Description
Technical Field
The invention relates to the technical field of detection of performance parameters of a photoetching machine, in particular to an on-line detection device and method for numerical aperture of a projection objective.
Background
This section provides merely background information related to the present disclosure and is not necessarily prior art.
The projection objective, the light source and the illumination system are arranged in parallel as three core components of the photoetching machine, the numerical aperture of the projection objective is a key parameter for measuring the performance of the projection objective and is also one of key parameters for influencing the photoetching resolution, and along with the improvement of the photoetching resolution, the numerical aperture of the projection objective is continuously increased, wherein the numerical aperture of the immersion photoetching machine reaches 1.35, so that the numerical aperture of the accurate projection objective becomes a key factor for influencing the photoetching resolution. Wherein the Numerical Aperture (NA) is the product of the refractive index (n) of the medium between the projection objective and the object to be projected (e.g. a chip) and the sine of the half angle θ of the illumination cone of the image side. The formula is na=n×sin θ.
At present, before the projection objective is integrated into the lithography machine, the method for measuring the numerical aperture of the projection objective in an offline mode is more and is easier to realize, but because the projection objective is sensitive to factors such as temperature, vibration and the like, the performance of the projection objective can change to a certain extent relative to the performance before the projection objective is integrated into the lithography machine, so that the method has great significance in the in-situ online measurement of the numerical aperture after the projection objective is integrated into the lithography machine.
Patent CN1021116706a proposes a device and a method for in-situ on-line measurement of numerical aperture of a projection objective, which adopts a specially designed object plane substrate, one side of the substrate is provided with a scattering element, a beam is filled with the projection objective through the scattering element, the other side of the substrate is provided with a pinhole mark, incident light emitted by the scattering element is imaged on an image plane after passing through the projection objective, and the pinhole mark achieves the purpose of measuring the numerical aperture through imaging measurement.
Disclosure of Invention
The invention aims at providing an on-line detection device for the numerical aperture of a projection objective, which aims at overcoming the defects of the prior art, and the on-line detection device can be used for carrying out in-situ on-line and rapid measurement on the numerical aperture of the projection objective after the installation is completed, so that the accuracy of the numerical aperture detection of the projection objective is improved. The aim is achieved by the following technical scheme.
The first aspect of the invention provides an on-line detection device for a numerical aperture of a projection objective, the projection objective being used in a lithography machine, the lithography machine comprising a light source, a mask table arranged at an object plane of the projection objective, a workpiece table arranged at an image plane of the projection objective, wherein the on-line detection device comprises a scattering element capable of being arranged on the mask table, and a numerical aperture measurement device capable of being arranged on the workpiece table, a scattered light beam of the light source passing through the scattering element covers the projection objective and is projected onto the numerical aperture measurement device by the projection objective, and the numerical aperture measurement device is capable of detecting the numerical aperture of the projection objective from a projection light beam of the scattered light beam projected onto the numerical aperture measurement device.
Preferably, the light source is an excimer laser, and when the scattering element is disposed on the mask stage and the outlet of the scattering element is disposed facing the projection objective, the scattering element can uniformly scatter the laser beam emitted by the excimer laser onto the projection objective.
Preferably, the numerical aperture measuring device comprises a projection detector and a small aperture plate arranged on the side of the projection detector facing the projection objective, through which the projection beam is projected onto the projection detector in a small aperture imaging manner.
Preferably, the aperture plate comprises a quartz substrate and a metal film layer partially covered on one side of the quartz substrate facing the projection objective, wherein a through hole is arranged in the middle of the metal film layer, and the projection light beam passes through the through hole and is refracted on the projection detector through the quartz substrate to form a projection light spot.
Preferably, the projection detector is a CCD detector, and the projection detector is used for acquiring the radius size of the projected light spot.
Preferably, the numerical aperture measurement device further comprises a controller connected to the projection detector, the controller determining the numerical aperture based on the thickness of the quartz substrate, the refractive index of the quartz substrate, the distance between the quartz substrate and the projection detector, and the radius of the projected spot.
The second aspect of the present invention also provides an on-line detection method for the numerical aperture of a projection objective, wherein the on-line detection method is implemented by the on-line detection device for the numerical aperture of the projection objective according to the first aspect of the present invention, and the on-line detection method comprises the steps of: s10, an excimer laser emits an excimer laser beam; s12, uniformly scattering a scattered light beam formed by the excimer laser beam passing through the scattering element on a projection object lens; s14, projecting the scattered light beam on a numerical aperture measuring device by a projection objective; and S16, the numerical aperture measuring device determines the numerical aperture of the projection objective according to the projection beam projected on the numerical aperture measuring device by the scattered beam.
Preferably, step S14 includes: s142, the projection objective projects the scattered light beam on a small pore plate on the numerical aperture measuring device to form a projection light beam; s144, forming a projection light spot on the projection detector in a small hole imaging mode by the projection light beam through the small hole plate.
Preferably, step S16 includes: the controller determines a numerical aperture according to the radius of the projection light spot, the thickness of the quartz substrate, the refractive index of the quartz substrate and the distance between the quartz substrate and the projection detector, wherein the measurement principle of the numerical aperture of the projection objective is as follows: the controller is configured to control the light beam to be projected according to the three points A (x 1 , y 1 )、B(x 2 ,y 2 ) And C (x) 3 ,y 3 ) The radius of the circle where the three points A, B and C are located is calculated, the center coordinates of the circle where the three points A, B and C are located are (a, b), and the radius is R, and then:
subtracting the second formula and the third formula from the first formula in the formula (1), and finishing to obtain the final product:
the expression for the radius R calculated by equation (2) is:
let the incidence angle of the scattered light beam incident on the through hole be theta, after the scattered light beam is refracted by the quartz substrate for the first time, the refraction angle is theta', and according to the refraction law and the geometric theory, the method comprises the following steps:
wherein t is the thickness of the quartz substrate, n' is the refractive index of the quartz substrate, h is the distance between the quartz substrate and the projection detector, the magnitude of the incident angle theta is calculated by the formula (4), the angle is the half angle of the illumination cone of the image side,
the numerical aperture of the projection objective is defined as the product of the refractive index n and the sine of the half angle θ of the illumination cone of the image side, expressed by the formula:
na=n×sin θ (5)
The numerical aperture NA of the projection objective is determined according to equation (5).
Preferably, between step S12 and step S14, further comprises: s13, adjusting the position of the numerical aperture measuring device by moving the workpiece table, so that the small pore plate on the numerical aperture measuring device is positioned at the image plane of the projection objective.
It can be understood by those skilled in the art that the on-line detection device for the numerical aperture of the projection objective can perform in-situ on-line and rapid measurement on the numerical aperture of the projection objective after the installation is completed, so that the accuracy of detecting the numerical aperture of the projection objective is improved. Specifically, after the projection objective is mounted to the lithography system, the scattering element of the online detection device is mounted to the mask table located at the object plane of the projection objective, the numerical aperture measuring device of the online detection device is mounted to the workpiece table located at the image plane of the projection object, the light source and the scattering element of the lithography system are utilized to project the light source and the scattering element of the lithography system to the numerical aperture measuring device through the projection objective, and the numerical aperture measuring device measures the numerical aperture of the projection objective according to the projection light beam, so that the purpose of in-situ online measurement of the numerical aperture of the projection objective is achieved, and the numerical aperture detection accuracy of the projection objective is improved.
Furthermore, the numerical aperture measuring device comprises a projection detector and a small pore plate arranged on one side of the projection detector facing the projection objective, the projection beam is projected on the projection detector through the small pore plate in a small pore imaging mode, and the projection detector determines the numerical aperture of the projection objective according to the projection light spots projected on the projection detector, so that the effect of accurately and rapidly measuring the numerical aperture of the projection objective is realized.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:
FIG. 1 is a schematic diagram of an on-line detection device for numerical aperture of a projection objective according to an embodiment of the present invention;
FIG. 2 is a schematic view of a projection beam passing through the on-line inspection apparatus of FIG. 1 according to one embodiment of the present invention;
FIG. 3 is a flow chart of an online detection method for detecting the numerical aperture of a projection objective according to an embodiment of the present invention;
12, a mask stage; 14. a work table; 16. a projection objective; 22. a scattering element; 24. a numerical aperture measuring device; 242. a metal film layer; 243. a quartz substrate; 244. a projection detector.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that, the application of the in-line detection device to detect the numerical aperture of the projection objective in the lithography system is only a preferred embodiment, and is not a limitation on the application range of the in-line detection device, for example, the in-line detection device of the present invention may also be used in other devices having a similar structure of the projection objective, and the adjustment does not deviate from the protection range of the in-line detection device of the present invention.
It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," and "having" are inclusive and therefore specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.
In the description of the present invention, unless explicitly stated and limited otherwise, the terms "disposed" and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention can be understood by those skilled in the art according to the specific circumstances.
For ease of description, spatially relative terms, such as "facing," "middle," "side," "inner," "outer," and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative relationship descriptors used herein interpreted accordingly.
Fig. 1 is a schematic structural view of an on-line detection device for numerical aperture of a projection objective according to an embodiment of the present invention.
As shown in fig. 1, a first aspect of the present invention provides an on-line detection device for a numerical aperture of a projection objective 16, the projection objective 16 being used in a lithography machine system, the lithography machine system comprising a light source (not shown in the figures), a mask table 12 arranged at an object plane of the projection objective 16, a workpiece table 14 arranged at an image plane of the projection objective 16, wherein the on-line detection device comprises a scattering element (described in detail below) which can be arranged on the mask table 12, a numerical aperture measuring device 24 which can be arranged on the workpiece table 14, a scattered light beam of the light source passing through the scattering element covering the projection objective 16 and being projected by the projection objective 16 onto the numerical aperture measuring device 24, the numerical aperture measuring device 24 being capable of detecting the numerical aperture of the projection objective 16 from the projected light beam of the scattered light beam onto the numerical aperture measuring device 24. Specifically, after the projection objective 16 is integrated into the lithography system, the scattering element of the in-line detection device of the present invention is mounted on the mask stage 12 of the lithography system at the object plane of the projection objective 16, and the numerical aperture measurement device 24 is mounted on the workpiece stage 14 of the lithography system at the image plane of the projection objective 16, wherein the scattered light beam emitted by the light source via the scattering element can cover the entire projection objective 16 and project the scattered light beam onto the numerical aperture measurement device 24 through the projection objective 16, and the numerical aperture measurement device 24 detects the numerical aperture of the projection objective 16 from the projected light beam of the scattered light beam. After the projection objective 16 is integrated into the photoetching machine system, the on-line detection device utilizes the mask table 12 and the workpiece table 14 of the photoetching machine system to measure the numerical aperture of the projection objective 16, thereby realizing the purpose of in-situ on-line measurement of the numerical aperture of the projection objective 16 and improving the accuracy of numerical aperture detection of the projection objective 16. It should be noted that, the mounting structure of the scattering element to the mask stage 12 may be a mounting structure of the mask to the mask stage 12, and the mounting structure of the numerical aperture measuring device 24 to the workpiece stage 14 may be a mounting structure of the chip to the workpiece stage 14, and the specific mounting manner will not be described herein.
With continued reference to fig. 1, according to an embodiment of the present invention, the light source is an excimer laser, and when the scattering element 22 is disposed on the mask stage 12 and the exit of the scattering element 22 is disposed facing the projection objective 16, the scattering element 22 can uniformly scatter the laser beam emitted by the excimer laser onto the projection objective 16. The excimer laser can use a laser emitter in a photoetching machine system, so that the cost of the online detection device is reduced, and the detection precision of the online detection device is improved.
With continued reference to FIG. 1, in accordance with an embodiment of the present invention, the numerical aperture measurement device 24 includes a projection detector 244 and an aperture plate (described in detail below) disposed on a side of the projection detector 244 facing the projection objective 16 through which the projection beam is projected onto the projection detector 244 in an aperture imaging manner. Specifically, the aperture plate is fixedly disposed on a side of the projection detector 244 facing the projection objective 16, and a gap is formed between the aperture plate and the projection detector 244, and the projection beam passes through the aperture plate and is projected onto the projection detector 244 in an aperture imaging manner.
FIG. 2 is a schematic diagram of a projection beam passing through the on-line inspection apparatus shown in FIG. 1 according to an embodiment of the present invention.
With continued reference to fig. 1 and reference to fig. 2, fig. 2 is a schematic diagram illustrating a projection beam passing through the on-line detection apparatus shown in fig. 1 according to an embodiment of the present invention. According to an embodiment of the invention, the aperture plate comprises a quartz substrate 243 and a metal film layer 242 partially covering one side of the quartz substrate 243 facing the projection objective 16, wherein a through hole is arranged in the middle of the metal film layer 242, and a projection light beam passes through the through hole and is refracted by the quartz substrate 243 to form a projection light spot on a projection detector 244. The quartz substrate 243 has a supporting light spot for the metal film 242.
With continued reference to fig. 1 and 2, in accordance with an embodiment of the invention, projection detector 244 comprises a CCD detector, and projection detector 244 is configured to collect the radial dimension of the projected spot. The CCD detector is a silicon-based multichannel array detector which can sense ultraviolet, visible and near infrared light, and as a preferred embodiment, the CCD detector of the invention can be an ultraviolet CCD detector.
With continued reference to fig. 1 and 2, according to an embodiment of the present invention, the numerical aperture measurement apparatus further includes a controller (not shown) connected to the projection detector 244, where the controller determines the numerical aperture according to the thickness t of the quartz substrate 243, the refractive index n' of the quartz substrate 243, the distance h between the quartz substrate 243 and the projection detector 244, and the radius R of the projection spot, the projection detector 244 collects three pixel points on the circumference of the projection spot, the controller obtains the radius R of the circumference of the projection spot according to the coordinates of the three pixel points, and then obtains the incident angle θ of the scattered light beam incident on the through hole on the aperture plate according to the refraction law and the aperture imaging principle, where the incident angle θ is the half angle of the illumination cone of the image side of the projection objective 16, thereby obtaining the numerical aperture of the projection objective 16.
With continued reference to fig. 1 and 2, in particular, the principle of measuring the numerical aperture of the projection objective 16 is: projection detector 244 collects three points a (x 1 ,y 1 )、B(x 2 ,y 2 ) And C (x) 3 ,y 3 ) The radius of the circumference where the three points A, B and C are located is calculated. Let the center coordinates of the circles where the three points A, B and C are located be (a, b), and the radius be R, then there are:
subtracting the second formula and the third formula from the first formula in the formula (1), and finishing to obtain the final product:
the expression for the radius R calculated by equation (2) is:
let the incidence angle of the scattered light beam incident on the through hole be θ, the refraction angle of the scattered light beam after first refraction through the quartz substrate 243 be θ', and there are:
wherein t is the thickness of the quartz substrate, n' is the refractive index of the quartz substrate, h is the distance between the quartz substrate and the projection detector, and the magnitude of the incident angle theta is calculated by the formula (4), and the angle is the half angle of the illumination cone of the image space.
The numerical aperture of the projection objective 16, defined as the product of the refractive index n and the positive chord value of the half angle θ of the illumination cone of the image space, is expressed as:
na=n×sin θ (5)
The numerical aperture NA of the projection objective 16 is determined according to equation (5).
Fig. 3 is a flow chart of an on-line detection method for detecting the numerical aperture of a projection objective according to an embodiment of the present invention.
With continued reference to fig. 1, 2 and 3, a second aspect of the present invention provides an on-line detection method of a numerical aperture of a projection objective 16 for an on-line detection apparatus of a numerical aperture of a projection objective 16 of the first aspect of the present invention, the on-line detection method comprising integrating the projection objective 16 into a lithography system and mounting a mask table 12 in the lithography system at an object plane of the projection objective 16, mounting a scattering element 22 onto the mask table 12, mounting an excimer laser onto a side of the scattering element 22 opposite the projection objective 16, mounting a workpiece table 14 in the lithography system at an image plane of the projection objective 16, mounting a numerical aperture measurement apparatus 24 onto the workpiece table 14, and then performing the steps of:
step S10: the excimer laser emits an excimer laser beam and the illumination system is adjusted to a suitable mode so that the excimer laser beam can be emitted to the scattering element 22;
step S12: the scattered light beam formed after the excimer laser beam passes through the scattering element 22 is scattered uniformly on the projection objective 16;
step S13: adjusting the position of the numerical aperture measuring device 24 by moving the workpiece stage 14 such that the aperture plate on the numerical aperture measuring device 24 is located at the image plane of the projection objective 16, in particular such that the aperture plate on the numerical aperture measuring device 24 is located at the focal distance at the image plane of the projection objective 16;
step S14: the projection objective 16 projects the scattered light beam onto a numerical aperture measuring device 24, the numerical aperture measuring device 24 comprising a small aperture plate and a projection detector 244 connected in sequence in the direction of the projection objective 16, wherein step S14 comprises: step S142, the projection objective 16 projects the scattered light beam onto the aperture plate on the numerical aperture measuring device 24 to form a projection light beam; step S144, forming a projection light spot on the projection detector 244 in a small hole imaging mode by the projection light beam through the small hole plate;
step S16: the numerical aperture measuring device 24 determines the numerical aperture of the projection objective 16 according to the projection spot of the scattered light beam projected on the numerical aperture measuring device 24, wherein the step S16 comprises: the controller determines the numerical aperture according to the radius of the projection spot, the thickness of the quartz substrate 243, the refractive index of the quartz substrate 243, and the distance between the quartz substrate 243 and the projection detector 244, and it should be noted that the workpiece stage 14 is a movable workpiece stage 14 controlled by the controller, and the controller controls the workpiece stage 14 to move according to the projection beam of the projection objective 16 until the aperture plate on the workpiece stage 14 is located at the image plane of the projection objective 16.
The on-line detection apparatus and method of the present invention will be described in further detail with reference to one embodiment.
Specific examples:
the illumination mode of the lithography system is set as a traditional illumination mode, and a projection objective 16 with a numerical aperture NA=0.75 is selected, a square through hole with a side length of 100 μm is arranged in the center of the small-aperture plate metal film layer 242, the thickness t of the quartz substrate 243 is set to be 2.28mm, the refractive index n' of the small-aperture plate quartz substrate 243 in 193nm wave band is= 1.5608, the distance from the small-aperture plate quartz substrate 243 to the projection detector 244 is 1.838 +/-0.037 mm, the workpiece stage 14 is set as a movable workpiece stage, the position of the projection detector 244 is adjusted through the movable workpiece stage, when the small-aperture plate on the projection detector 244 is positioned at the image plane of the projection objective 16, the position of a projection spot on the projection detector 244 is acquired, and the controller calculates the numerical aperture of the projection objective 16 to be 0.7505 according to formulas (1) - (5).
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the technical scope of the present invention should be covered by the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (9)
1. An on-line detection device for a numerical aperture of a projection objective, the projection objective being used in a lithography machine system, the lithography machine system comprising a light source, a mask table arranged at an object plane of the projection objective, a workpiece table arranged at an image plane of the projection objective, characterized in that the on-line detection device comprises a scattering element capable of being arranged on the mask table, a numerical aperture measurement device capable of being arranged on the workpiece table, a scattered light beam of the light source passing through the scattering element covers the projection objective and is projected on the numerical aperture measurement device by the projection objective, the numerical aperture measurement device being capable of detecting the numerical aperture of the projection objective from a projection light beam of the scattered light beam projected on the numerical aperture measurement device;
the numerical aperture measuring device comprises a projection detector and a small pore plate arranged on one side of the projection detector facing the projection objective, and the projection beam is projected on the projection detector through the small pore plate in a small pore imaging mode;
the workpiece stage is arranged as a movable workpiece stage, and the position of the projection detector is adjusted through the movable workpiece stage.
2. The device according to claim 1, wherein the light source is an excimer laser, and the scattering element is capable of uniformly scattering a laser beam emitted by the excimer laser onto the projection objective when the scattering element is disposed on the mask stage and an outlet of the scattering element is disposed facing the projection objective.
3. The on-line detection device for the numerical aperture of the projection objective according to claim 1, wherein the aperture plate comprises a quartz substrate and a metal film layer partially covering one side of the quartz substrate facing the projection objective, a through hole is arranged in the middle of the metal film layer, and the projection light beam passes through the through hole and is refracted by the quartz substrate to form a projection light spot on the projection detector.
4. An on-line detection device for the numerical aperture of a projection objective according to claim 3, wherein the projection detector is a CCD detector for acquiring the radial dimension of the projected spot.
5. The on-line detection device of the numerical aperture of the projection objective according to claim 4, further comprising a controller connected to the projection detector, the controller determining the numerical aperture based on a radius of the projected spot in combination with a thickness of the quartz substrate, a refractive index of the quartz substrate, a distance between the quartz substrate and the projection detector.
6. An on-line detection method of the numerical aperture of a projection objective, characterized in that the on-line detection method is implemented according to an on-line detection device of the numerical aperture of a projection objective according to any one of claims 1 to 5, the on-line detection method comprising the steps of:
s10: the excimer laser emits an excimer laser beam;
s12, uniformly scattering the scattered light beam formed by the excimer laser beam passing through the scattering element on the projection objective;
s14, the projection objective projects the scattered light beam on the numerical aperture measuring device;
s16, the numerical aperture measuring device determines the numerical aperture of the projection objective according to the projection beam projected on the numerical aperture measuring device by the scattered beam;
the numerical aperture measuring device comprises a projection detector and a small pore plate arranged on one side of the projection detector facing the projection objective, and the projection beam passes through the small pore plate and is projected on the projection detector in a small pore imaging mode.
7. The method of on-line detection of the numerical aperture of a projection objective according to claim 6, wherein step S14 comprises:
s142, the projection objective projects the scattered light beam on a small pore plate on the numerical aperture measuring device to form a projection light beam;
s144, forming a projection light spot on a projection detector in a small hole imaging mode through the small hole plate by the projection light beam.
8. The method of on-line detection of the numerical aperture of a projection objective according to claim 7, wherein step S16 comprises: the controller determines the numerical aperture based on the radius of the projected spot in combination with the thickness of the quartz substrate, the refractive index of the quartz substrate, the distance between the quartz substrate and the projection detector,
the measuring principle of the numerical aperture of the projection objective is as follows: the controller is configured to control the light beam to be projected according to the three points A (x 1 ,y 1 )、B(x 2 ,y 2 ) And C (x) 3 ,y 3 ) The radius of the circle where the three points A, B and C are located is calculated, the center coordinates of the circle where the three points A, B and C are located are (a, b), and the radius is R, and then:
subtracting the second formula and the third formula from the first formula in the formula (1), and finishing to obtain the final product:
the expression for the radius R calculated by equation (2) is:
let the incidence angle of the scattered light beam incident on the through hole be theta, after the scattered light beam is refracted by the quartz substrate for the first time, the refraction angle is theta', and according to the law of refraction and the geometric theory, the method comprises the following steps:
wherein t is the thickness of the quartz substrate, n' is the refractive index of the quartz substrate, h is the distance between the quartz substrate and the projection detector, the magnitude of the incident angle theta is calculated by the formula (4), the angle is the half angle of the illumination cone of the image side,
the numerical aperture of the projection objective is defined as the product of the refractive index n and the sine of the half angle θ of the illumination cone of the image side, expressed as:
na=n×sin θ (5)
The numerical aperture NA of the projection objective is determined according to equation (5).
9. The method of on-line detection of the numerical aperture of a projection objective according to claim 8, further comprising between step S12 and step S14:
and S13, adjusting the position of the numerical aperture measuring device by moving the workpiece table, so that the small pore plate on the numerical aperture measuring device is positioned at the image plane of the projection objective.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810416484.6A CN108803248B (en) | 2018-05-03 | 2018-05-03 | On-line detection device and method for numerical aperture of projection objective |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810416484.6A CN108803248B (en) | 2018-05-03 | 2018-05-03 | On-line detection device and method for numerical aperture of projection objective |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108803248A CN108803248A (en) | 2018-11-13 |
| CN108803248B true CN108803248B (en) | 2024-04-02 |
Family
ID=64093573
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810416484.6A Active CN108803248B (en) | 2018-05-03 | 2018-05-03 | On-line detection device and method for numerical aperture of projection objective |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108803248B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109916598A (en) * | 2019-04-26 | 2019-06-21 | 北京航空航天大学 | A kind of microcobjective numerical aperture measurement method based on diffraction grating |
| CN110686871B (en) * | 2019-05-20 | 2021-08-27 | 苏州大学 | Numerical aperture measuring device and method of self-focusing lens |
| CN110082077B (en) * | 2019-06-19 | 2024-05-28 | 无锡奥普特自动化技术有限公司 | Optical fiber numerical aperture measuring instrument |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116706A (en) * | 2010-01-04 | 2011-07-06 | 上海微电子装备有限公司 | Measurement device and method for numerical aperture of projection objective |
| CN102375329A (en) * | 2010-08-20 | 2012-03-14 | 上海微电子装备有限公司 | Test mask and method for measuring exposure system parameters therewith |
| CN103439868A (en) * | 2013-09-01 | 2013-12-11 | 中国科学院光电技术研究所 | Device and method for measuring numerical aperture of projection objective |
| CN104198159A (en) * | 2014-07-31 | 2014-12-10 | 中国科学院长春光学精密机械与物理研究所 | Detection device and method for wave aberration of high-numerical aperture objective lens |
| CN106324996A (en) * | 2015-06-15 | 2017-01-11 | 中国科学院上海光学精密机械研究所 | Photoetching machine in-situ multichannel imaging quality detection apparatus and photoetching machine in-situ multichannel imaging quality detection method |
| CN208207508U (en) * | 2018-05-03 | 2018-12-07 | 中国科学院光电研究院 | On-line measuring device for Optical Coatings for Photolithography |
-
2018
- 2018-05-03 CN CN201810416484.6A patent/CN108803248B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102116706A (en) * | 2010-01-04 | 2011-07-06 | 上海微电子装备有限公司 | Measurement device and method for numerical aperture of projection objective |
| CN102375329A (en) * | 2010-08-20 | 2012-03-14 | 上海微电子装备有限公司 | Test mask and method for measuring exposure system parameters therewith |
| CN103439868A (en) * | 2013-09-01 | 2013-12-11 | 中国科学院光电技术研究所 | Device and method for measuring numerical aperture of projection objective |
| CN104198159A (en) * | 2014-07-31 | 2014-12-10 | 中国科学院长春光学精密机械与物理研究所 | Detection device and method for wave aberration of high-numerical aperture objective lens |
| CN106324996A (en) * | 2015-06-15 | 2017-01-11 | 中国科学院上海光学精密机械研究所 | Photoetching machine in-situ multichannel imaging quality detection apparatus and photoetching machine in-situ multichannel imaging quality detection method |
| CN208207508U (en) * | 2018-05-03 | 2018-12-07 | 中国科学院光电研究院 | On-line measuring device for Optical Coatings for Photolithography |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108803248A (en) | 2018-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7420670B2 (en) | Measuring instrument and method for operating a measuring instrument for optical inspection of an object | |
| CN103309169B (en) | The method of pick-up unit, exposure device and manufacture device | |
| CN108803248B (en) | On-line detection device and method for numerical aperture of projection objective | |
| KR101149842B1 (en) | Method of determining defects in a substrate and apparatus for exposing a substrate in a lithographic process | |
| JP2008275612A (en) | Device equipped with high resolution measurement structure on substrate for manufacturing semiconductor, and use of aperture in measuring device | |
| JPWO2005096354A1 (en) | Exposure apparatus, exposure method and device manufacturing method, and surface shape detection apparatus | |
| US9400436B2 (en) | Detection device, exposure apparatus, and device manufacturing method using same | |
| JP2016539375A (en) | Apparatus and method for positioning a photolithographic mask using non-contact optical methods | |
| JP3477777B2 (en) | Projection exposure apparatus and method | |
| JP2006337374A (en) | Device and method for improving measurement precision when finding structural data | |
| CN101169594B (en) | Photo-etching machine imaging quality measuring method | |
| TWI460559B (en) | Level sensor arrangement for lithographic apparatus, lithographic apparatus and device manufacturing method | |
| US9036152B2 (en) | Method and apparatus for determining the absorption in a blank | |
| TWI505040B (en) | Lithographic apparatus, method for measuring radiation beam spot focus and device manufacturing method | |
| CN208207508U (en) | On-line measuring device for Optical Coatings for Photolithography | |
| US11221565B2 (en) | Level sensor and lithographic apparatus | |
| US6580492B2 (en) | Reticle system for measurement of effective coherence factors | |
| CN102200690B (en) | On-line measuring mark of image plane of lithography machine projection objective and measuring method | |
| US11106144B2 (en) | Lithographic method and apparatus | |
| JPH026709A (en) | Surface displacement detector | |
| JPH09120940A (en) | Alignment and aligner | |
| Horie et al. | Film thickness measurement tool with a stress measurement function | |
| JPS61180436A (en) | Projection exposure device | |
| JPH04177822A (en) | Observation device | |
| JP2011171477A (en) | Exposure device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |