CN106517086B - A kind of large area high-resolution wide visual field on-line measurement device and its measurement method - Google Patents
A kind of large area high-resolution wide visual field on-line measurement device and its measurement method Download PDFInfo
- Publication number
- CN106517086B CN106517086B CN201610921773.2A CN201610921773A CN106517086B CN 106517086 B CN106517086 B CN 106517086B CN 201610921773 A CN201610921773 A CN 201610921773A CN 106517086 B CN106517086 B CN 106517086B
- Authority
- CN
- China
- Prior art keywords
- measured
- unit
- nano structure
- light
- imaging
- 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
- 238000005259 measurement Methods 0.000 title claims abstract description 55
- 230000000007 visual effect Effects 0.000 title abstract description 18
- 238000000691 measurement method Methods 0.000 title abstract description 8
- 238000003384 imaging method Methods 0.000 claims abstract description 139
- 230000010287 polarization Effects 0.000 claims abstract description 107
- 239000002086 nanomaterial Substances 0.000 claims abstract description 93
- 239000012528 membrane Substances 0.000 claims abstract description 72
- 238000000572 ellipsometry Methods 0.000 claims abstract description 26
- 230000003595 spectral effect Effects 0.000 claims abstract description 21
- 230000003287 optical effect Effects 0.000 claims description 51
- 239000011159 matrix material Substances 0.000 claims description 31
- 239000010408 film Substances 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 27
- 239000013307 optical fiber Substances 0.000 claims description 18
- 239000005262 ferroelectric liquid crystals (FLCs) Substances 0.000 claims description 14
- 239000000835 fiber Substances 0.000 claims description 14
- 238000004458 analytical method Methods 0.000 claims description 13
- 230000021615 conjugation Effects 0.000 claims description 8
- 230000001360 synchronised effect Effects 0.000 claims description 7
- 239000010409 thin film Substances 0.000 claims description 7
- 238000000605 extraction Methods 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 description 15
- 238000005516 engineering process Methods 0.000 description 9
- 230000014509 gene expression Effects 0.000 description 9
- 238000000391 spectroscopic ellipsometry Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000008901 benefit Effects 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 5
- 238000013461 design Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000005457 optimization Methods 0.000 description 4
- 238000000411 transmission spectrum Methods 0.000 description 4
- 239000013598 vector Substances 0.000 description 4
- 101150118300 cos gene Proteins 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 238000005286 illumination Methods 0.000 description 3
- 239000004973 liquid crystal related substance Substances 0.000 description 3
- 241000208340 Araliaceae Species 0.000 description 2
- 101100234408 Danio rerio kif7 gene Proteins 0.000 description 2
- 101100221620 Drosophila melanogaster cos gene Proteins 0.000 description 2
- 240000007594 Oryza sativa Species 0.000 description 2
- 235000007164 Oryza sativa Nutrition 0.000 description 2
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 description 2
- 235000003140 Panax quinquefolius Nutrition 0.000 description 2
- 101100398237 Xenopus tropicalis kif11 gene Proteins 0.000 description 2
- 230000008033 biological extinction Effects 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 238000007405 data analysis Methods 0.000 description 2
- 230000001066 destructive effect Effects 0.000 description 2
- 230000005672 electromagnetic field Effects 0.000 description 2
- 235000008434 ginseng Nutrition 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 238000001259 photo etching Methods 0.000 description 2
- 235000009566 rice Nutrition 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 238000000205 computational method Methods 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005621 ferroelectricity Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005305 interferometry Methods 0.000 description 1
- 238000012886 linear function Methods 0.000 description 1
- 238000012417 linear regression Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000000879 optical micrograph Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82B—NANOSTRUCTURES FORMED BY MANIPULATION OF INDIVIDUAL ATOMS, MOLECULES, OR LIMITED COLLECTIONS OF ATOMS OR MOLECULES AS DISCRETE UNITS; MANUFACTURE OR TREATMENT THEREOF
- B82B3/00—Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
- B82B3/0085—Testing nanostructures
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y35/00—Methods or apparatus for measurement or analysis of nanostructures
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Nanotechnology (AREA)
- Crystallography & Structural Chemistry (AREA)
- Analytical Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses one kind towards nano structure membrane large area, high-resolution, wide visual field on-line measurement device and measurement method.The light that light source is sent out becomes Single wavelength light beam and is converted into elliptical polarization light beam to project on nano structure membrane to be measured by wavelength selector.The film reflector light beam obtains the imaging spectral ellipsometry data of nano structure membrane to be measured by imaging unit and Polarization unit into planar array detector.The data and theoretical value matching, extraction obtain the parameter value of nano structure membrane to be measured at corresponding pixel points, and the parameter value extracted constitutes the three-dimensional microstructure of nano structure membrane to be measured.Correspondingly, the invention also discloses a kind of measurement methods.The present invention can solve the problems, such as that existing apparatus instrument depth of focus value very little, device are difficult to realize that wide visual field blur-free imaging and high lateral resolution measure simultaneously, really realize that the large area high-resolution of nano structure membrane accurately measures.
Description
Technical field
The invention belongs to large-area nano structures in nanometer manufacture, the especially manufacture of scale nanometer and flexible electronic manufacture
The online process of film monitors and optimization control field, and in particular to a kind of nano structure membrane large area high-resolution (including
Longitudinal resolution and lateral resolution) wide visual field on-line measurement measuring device and its measurement method.
Background technology
Nanometer manufacture refers to the manufacturing technology that product feature size is nanometer scale, i.e., characteristic size is within 100nm
Manufacturing technology.In order to reduce a nanometer manufacturing cost, in recent years in new industries such as flexible electronic, photovoltaic, FPD
In field, mostly uses roll-to-roll (roll-to-roll) or piece and work is manufactured to the extensive nanometer such as piece (sheet-to-sheet)
Skill.In order to realize effective process monitoring, to the light of nano structure membrane in the especially extensive nanometer manufacture of nanometer manufacture
Learn constant, film thickness, nano structure line width, line height, the geometric parameters such as side wall angle carry out large area, quickly, low cost, non-break
The accurate measurement of bad property has a very important significance.In addition, in some extensive nanometer manufactures, to large-area nano structure
When film measures, often require that measurement means are provided simultaneously with higher longitudinal resolution and lateral resolution.It is aobvious with tablet
For Organic Light Emitting Diode (OLED) manufacturing process shown, the organic film in OLED is usually very thin, only hundred nanometers
Magnitude, and each pixel in OLED is made of R sub-pixels, G sub-pixel and each one of B sub-pixels, each sub-pixel unit
Size in micron dimension.In order to realize the accurate survey to organic film thickness in each sub-pixel unit and optical characteristics
Amount, the lateral resolution of the longitudinal resolution and micron dimension of nanometer scale must be provided simultaneously with this requires measurement means.
The measurements such as conventional scanning electron microscope (SEM), atomic force microscope (AFM) and transmission electron microscope (TEM)
Means can meet the measurement request of nano-grade size, but the disadvantage is that speed is slow, of high cost, equipment operation is complicated, is difficult to
The optical characteristics such as the optical constant for being integrated on manufacturing process line and realizing on-line measurement, and be not used to characterization material.With
Compare, measuring method has many advantages, such as fast measuring speed, at low cost, contactless, non-destructive and is easy to Online integration,
Thus it is applied widely with optimization control field in advanced process-monitor always.Traditional optical measurement method such as optical microphotograph
Mirror can realize the measurement of micron dimension lateral resolution geometric dimension, can reach especially by optimization instrument light path design
Lateral resolution corresponding to optical resolution limit, but light microscope cannot be normal to the thickness and its optics of thin-film material
Number measures.The interference micrometering technology further developed on the basis of light microscope, can realizeMagnitude
The accurate measurement of longitudinal resolution and 1 μm or so lateral resolution geometric dimension, but cannot be to the optical constant of thin-film material
Carry out accurate characterization.Although also there is the report for measuring refractive index using interferometry in document, often needed in specific measure
The thickness of sample is known in advance, and device is more complicated.
Transmission spectra ellipsometry method is that a kind of change by measuring the polarization state of light is thin to obtain sample to be tested
The measuring method of the information such as film thickness and its optical constant, film thickness measuring precision (longitudinal resolution) can reachIts optical constant measurement accuracy can generally achieve 10-4Magnitude.Spectroscopic ellipsometry technology starts before and after 2000
Applied to the measurement of sub-wavelength nanostructure critical size, be usually otherwise known as optical scattering measurement technology at this time.In recent years, with
The continuous promotion of nanometer manufacturing technology level, the optical scattering measurement technology based on transmission spectra ellipsometry is received in scale
The metric system makes middle nano structure membrane geometric parameter and the on-line measurement aspect of optical constant etc. is more and more widely used.
Although spectroscopic ellipsometry method has higher longitudinal resolution, lateral resolution is by exposing to the light of sample surfaces
Spot diameter is determined with sample stage mobile accuracy, usually in millimeter magnitude.It is even added after micro- laser spot detection light path, transverse direction
Resolution ratio is general at most also can only be in 25~50 μm of magnitudes.It is ellipse that a kind of imaging spectral is disclosed in patent CN201410733437.6
Inclined measuring technique, which is combined spectroscopic ellipsometry technology with micro-imaging technique, to make full use of Spectroscopic Ellipsometry
The advantages of high longitudinal resolution of measuring technique is with micro-imaging technique high lateral resolution.Dress is but measured disclosed in the patent
It sets due to its one-step image reconstruction light channel structure based on conventional bevel mirror image system, the depth of focus value very little of instrument so that the dress
It sets and is difficult to realize that wide visual field blur-free imaging is measured with high lateral resolution simultaneously, also just can not really realize nano structure membrane
Large area high-resolution accurately measures.
Invention content
The defect of measurement demand and existing measuring technique in being manufactured for extensive nanometer, the present invention provide one kind and receive
Rice structural membrane geometric parameter large area high-resolution wide visual field on-line measurement device and its measurement method, to solve existing dress
Set instrument depth of focus value very little, device is difficult to realize that wide visual field blur-free imaging and high lateral resolution measure problem, real reality simultaneously
The large area high-resolution of existing nano structure membrane accurately measures.
Technical solution of the present invention is：A kind of nano structure membrane large area high-resolution wide visual field on-line measurement device, packet
It includes and is polarized arm (8) and analyzing arm (24) wherein：
Arm (8) and the analyzing arm (24) of being polarized is respectively with thin film planar normal to be measured at identical inclination angle；
It is described to be polarized arm (8) and incident light is coaxial, for collimating external light source incident light, collimated light beam is obtained,
Polarization state modulation is carried out to incident light simultaneously, obtains elliptically polarized light；
The analyzing arm (24) is located at light reflecting thin film road to be measured, single by relay imaging unit (14), vertical imaging
First (18) and Polarization unit (22) put composition successively；Wherein：
The relay imaging unit (14) is put by front lens (12) and rear lens (13) according to optical axis coincidence, focal length conjugation
Composition；Its front focus is overlapped with thin film center to be measured；
The vertical imaging unit (18) is put by high-NA objective (16) and tube lens (17) common optical axis conjugation；
The back focal plane of tube lens (17) is equipped with the sensitive chip of planar array detector (23), for realizing blur-free imaging；
Relay imaging unit (14) back focal length is conjugated with the front focal length of vertical imaging unit (18), and between the two
Optical axis included angle meets formula, wherein the incidence angle for external light source relative to film to be measured, and front lens (12) is corresponded to respectively
The front focal plane focal length of back focal plane focal length and rear lens (13)；Vertical imaging unit (18) is with Polarization unit (22) using altogether
Optical axis is put；To realize the wide visual field blur-free imaging and high resolution measurement of instrument；
The Polarization unit (22) is used to carry out Polarization to the light beam that vertical imaging unit (18) is emitted,
To measure the ellipsometric parameter of sample to be tested.
Further, the arm that is polarized includes that collimation lens (5) and polarization state generate unit PSG (7), and the two is set with optical axis
It sets, the collimation lens is sent into polarization state and generates unit PSG (7) realization polarizations for being collimated to external light source incidence light
The modulation of state.
Further, it includes the polarizer (6) that the polarization state, which generates unit PSG (7), corresponds to Polarization unit at this time
(22) it is made of the phase compensator (20) and analyzer (21) that rotate；
Further, the polarization state generates phase compensator (28) groups of unit PSG (7) by the polarizer (6) and rotation
At corresponding to Polarization unit at this time and be made of analyzer (21).
Further, the polarization state generates the polarizer, the preceding ferroelectric liquid crystals device that unit (7) is arranged by sequentially common optical axis
Part, quarter wave plate and rear ferroelectric liquid crystal devices (4) composition, correspond to Polarization unit (22) by ferroelectric liquid crystal devices at this time
(5), quarter wave plate (6), ferroelectric liquid crystal devices (7) and analyzer (8) common optical axis are put successively；By controlling 4 ferroelectric liquid crystals devices
The voltage direction of part generates 2 kinds of different conditions of ferroelectric phase and paraelectric phase, to generate the polarised light of 4 kinds of different polarization states, warp
Polarization unit obtains all 16 elements in the Muller matrix M of sample to be tested.
Further, the polarization state generates unit (7) and is made of the phase compensator (28) of the polarizer (6) and rotation,
It corresponds to Polarization unit at this time to be made of the phase compensator (20) and analyzer (21) rotated, and phase compensator (28)
Fast axle with phase compensator (20) is with certain rotating ratio synchronous rotary；Rotating ratio is preferably 5:1,5:2 and 5:3.
Further, the external light source includes light source (1), wavelength selector (2), fiber coupler (3) and output light
Fine (4)；The light that light source (1) generates is changed into single-wavelength light through wavelength selector (2), and output optical fibre is sent through fiber coupler (3)
(4), output optical fibre (4) is the output end of external light source.
Further, further include control system, the control system and it is synchronous setting be connected, the synchronizing device be located at
It is polarized the first hollow motor (29) in arm (8) with the second hollow motor (19) in analyzing arm (24) to be connected, for controlling in two-arm
Phase compensator with certain rotating ratio synchronous rotary, and then realize the modulation and demodulation of polarization state.
It is another aspect of this invention to provide that the present invention also proposes a kind of nano structure membrane large area high-resolution wide visual field
On-line Measuring Method includes the following steps：
(1) nano structure membrane to be measured is placed on sample stage；
(2) imaging optical path is adjusted, the blur-free imaging in sample region to be measured is obtained on planar array detector；
(3) Single wavelength collimated light beam is obtained elliptically polarized light and be projected to after polarization state generation unit is modulated
Nano structure membrane surface to be measured；
(4) it after carrying out polarization state demodulation to nano structure membrane surface reflection to be measured, enters in planar array detector, obtains
Reflective light intensity signal under to different polarization state；
(5) nano structure membrane corresponding surface battle array detection to be measured is calculated in the reflective light intensity signal obtained according to (4) step
Measurement ellipsometric parameter on device at each pixel, the corresponding measurement ellipsometric parameter of all pixels point are constituted in entire field of view
The imaging ellipsometry data of sample to be tested
(6) change incident beam wavelength and incident beam incidence angle, rotation sample stage with change incident beam with
Institute is at azimuth between nano structure membrane to be measured；(2) step~the (5) step is repeated, different wave length, incidence can be calculated
Actual imaging ellipsometric data under angle and azimuth configuration；
(7) under given wavelength, incidence angle and azimuth configuration, calculate nano structure membrane to be measured it is corresponding it is theoretical at
As ellipsometric data；When sample is film, calculated using fresnel formula；When sample is nanostructure, using stringent
Coupled Wave Analysis (RCWA), FInite Element (FEM), boundary element method (BEM) or finite time-domain calculus of finite differences (FDTD) are calculated；
(8) it calculates actually measuring arbitrary pixel on obtained imaging spectral ellipsometric data, the picture can be obtained
The parameter value to be measured of corresponding nanostructure at vegetarian refreshments；The parameter value to be measured for completing the corresponding nanostructure of all pixels point is asked
Solution finally obtains the three-dimensional microstructure of nanostructure to be measured in entire field of view.
Three-dimensional microstructure of the present invention includes nanometer size of three-dimensional structure cross direction profiles and longitudinal height.It is described
Ellipsometric parameter includes the amplitude ratio angle for measuring sample to be tested, phase angle and the full Muller matrix M for measuring sample to be tested.
Nano structure membrane geometric parameter large area high-resolution wide visual field on-line measurement device provided by the invention, it is special
Sign is that the device adds wavelength selector (such as adjustable filtering of monochromator, acousto-optic in being polarized in light path for transmission spectra ellipsometer
Device or liquid crystal tunable filter), to realize continuously adjusting for wavelength, two step imaging optical path systems are had additional in analyzing light path
System, corresponds to relay imaging unit and vertical imaging unit respectively, while by the linear array detector (such as spectrometer) in analyzing light path
Planar array detector (such as CCD CMOS cameras) is replaced with, to collect nano structure membrane to be measured in entire imaging viewing field region
Imaging spectral ellipsometry data.After the imaging spectral ellipsometry data for obtaining sample to be tested, by image
Each pixel carries out independent Ellipsometry Measurement, can accurately reconstruct the large area region for including entire imaging viewing field in real time
The geometric parameter three-dimensional microstructure of interior nano structure membrane to be measured and optical constant three-dimensional microstructure.
Compared with imaging spectral elliptical bias detector disclosed in patent CN201410733437.6, survey provided by the invention
Measuring device has and its comparable longitudinal resolution (measurement accuracy for depending on spectroscopic ellipsometers).The difference is that patent
The lateral resolution of imaging spectral elliptical bias detector is relatively low disclosed in CN201410733437.6 and cannot achieve wide visual field
Blur-free imaging, and measuring device provided by the invention can be realized simultaneously high lateral resolution and measure and comprising entire imaging viewing field
The wide visual field blur-free imaging in region.This is because imaging spectral ellipsometry disclosed in patent CN201410733437.6 fills
It sets, imaging optical path is substantially a tilting mirrors imaging system, angle of inclination, that is, incident beam optical axis and sample to be tested surface
Angle theta between normal (for different materials, θ values are generally at 55 °~75 °) generally near Brewster angle.It is tilting
Under imaging pattern, due to the limitation of system depth of focus, in entire imaging viewing field sample to be tested surface clearly region only one
Long and narrow belt-like zone, the sample surfaces except this region are all fuzzy.Be capable of the width of blur-free imaging belt-like zone with
The numerical aperture (NA) of imaging len and sin θ are inversely proportional in imaging system.Obviously, in the case where θ is certain, NA is smaller, clearly
Imaging region is wider.However, NA is bigger, the lateral resolution of system is lower.
The image-forming principle of two steps imaging optical path system provided by the invention is as shown in Figure 1.Wherein, θ is incidence angle (reflection
Angle), lens 3 and lens 4 constitute relay imaging unit 2；Lens 7 and lens 8 constitute vertical imaging unit 6.Lens 3 and lens 4
Optical axis coincidence arrange that the optical axis coincidence of lens 7 and lens 8 is using conjugate focal distances arrangement, the preceding coke of lens 7 using conjugate focal distances
Away from the back focal length with lens 4 also using conjugation arrangement.Between the optical axis of relay imaging unit and the optical axis of vertical imaging unit at
Certain angle theta ', the relationship between θ ' and θ is determined by following formula：
Wherein f1And f2The focal length of lens 3 and lens 4, f are corresponded to respectively2/f1It is also the times magnification of relay imaging unit simultaneously
Rate.Sample region 1 to be measured is located at the front focal plane of lens 3, is located at lens 4 by the image 5 obtained after relay imaging unit 2
Back focal plane at, while also being located at the front focal plane of lens 7.Image 5 obtains image 9, image after vertical imaging unit 6
9 are further obtained by the photosurface of planar array detector and carry out subsequent data processing.
The numerical aperture NA of lens 3 in two steps imaging optical path system provided by the invention1Determine entire imaging system
Lateral resolution, numerical value can estimate by following formula：
Wherein c is constant, and λ is illumination light wavelength, and ε is that the minimal transverse distance that imaging system can be respectively (can be according to setting
Meter requires to determine).Under the conditions of incoherent illumination, c=0.61；Under the conditions of coherent illumination, c=0.77.The main use of lens 7
Way is to collect the light beam being emitted from relaying imaging unit, numerical aperture NA as much as possible2Value can be estimated by following formula：
NA2=nsin θ ' (3)
Wherein n is object space medium refractive index.When medium is air, n=1.The selection of lens 4 and lens 8 is mainly simultaneous
Care for the enlargement ratio M of entire imaging system：
Wherein f3And f4The focal length of lens 7 and lens 8, f are corresponded to respectively4/f3For the enlargement ratio of vertical imaging unit.For
So that analyzing light path is compact, the enlargement ratio f of general relay imaging unit2/f1≤1。
As an improvement of the above technical solution, apparatus of the present invention specifically include light source, wavelength selector, fiber coupler,
Optical fiber, collimating mirror are drawn, polarization state generates unit (PSG), is polarized arm, the rotation sample for placing nano structure membrane to be measured
Platform, goniometer, relay imaging unit, vertical imaging unit, Polarization unit (PSA), analyzing arm, planar array detector, control
Device processed, synchronizing device and computer.Light source, wavelength selector and fiber coupler are located in same light path, lead between three
Optical fiber connection is crossed, the one end for drawing optical fiber is connected on fiber coupler, is located at standard from the light beam that the optical fiber other end is drawn is drawn
The focal position of straight mirror.Collimating mirror and polarization state generation unit, which are located at, is polarized light path, and is mounted on and is polarized on arm；Relay imaging
Unit, vertical imaging unit and Polarization unit are located at analyzing light path, and on analyzing arm.It is polarized arm and analyzing
Arm is symmetrically arranged in identical inclination angle theta on goniometer, and polarization state therein generates unit with Polarization unit by controlling
Device controls and is connected with computer.Vertical imaging unit and Polarization unit in analyzing light path are designed using common optical axis,
Its optical axis and relay imaging cell optic axis form an angle θ ', and the angle can by the goniometer on analyzing arm into
Row is adjusted.The region to be measured of sample is located in the front end focus of relay imaging unit, relay imaging unit and vertical imaging unit
Between focal length using conjugation arrange, planar array detector be mounted on vertical imaging unit rear end focal plane after, to ensure to acquire
The clarity of image.
It is provided by the invention to carry out nano structure membrane optical constant and film thickness, nano structure using above-mentioned apparatus
The geometric parameters large area such as line width, line height, side wall angle, high-resolution, wide visual field, on-line measurement method, specifically include following
Step：
Nano structure membrane to be measured is placed on specimen rotating holder by the 1st step, debugs light path, so that planar array detector is obtained to be measured
The blur-free imaging in region；
The light beam that 2nd step is sent out by light source successively becomes parallel beam by wavelength selector and collimation lens, then
It is generated after unit obtains elliptical polarization light beam by polarization state and is projected to nano structure membrane surface to be measured；
3rd step elliptical polarization light beam successively passes through relay imaging unit after nano structure membrane surface reflection to be measured
With vertical imaging unit planar array detector is finally entered using Polarization unit.It collects to obtain using planar array detector
Reflected light (when sample to be tested is periodic nano-structure, reflected light corresponds to survey the zero-order diffraction light of nanostructure) is corresponding
Light intensity signal generates unit with Polarization unit to collect to obtain reflected light under different polarization state by controlling polarization state
Light intensity signal；
Nano structure membrane corresponding surface to be measured is calculated in the light intensity signal for the reflected light that 4th step is collected into according to the 3rd step
Measurement ellipsometric parameter (i.e. amplitude ratio angle Ψ and phase angle Δ or Muller matrix M) on array detector at each pixel,
The corresponding imaging ellipsometry data for measuring ellipsometric parameter and constituting sample to be tested in entire field of view of all pixels point；
5th step changes the wavelength X of incident beam using wavelength selector, and rotation is polarized arm and analyzing arm to change incident light
The incidence angle θ (needing to adjust the angle theta ' between relay imaging cell optic axis and vertical imaging unit optical axis simultaneously) of beam, rotation
Sample stage is (square when sample to be tested is film at azimuth φ to change institute between incident beam and nano structure membrane to be measured
Parallactic angle φ can be fixed as arbitrary value；When sample to be tested is periodic nano-structure, azimuth φ is defined as the plane of incidence and sample
Product surface intersection line is with nanostructure period to be measured direction angulation)；The step of the 2nd step~the 4th is repeated, different wave length, incidence are obtained
Imaging ellipsometry data under angle and azimuth configuration；
6th step calculates the corresponding theory of nano structure membrane to be measured under given wavelength, incidence angle and azimuth configuration
Ellipsometric parameter；
7th step will be each on the theoretical ellipsometric parameter that the 6th step is calculated and imaging ellipsometry data that the 5th step obtains
Pixel or the corresponding measurement ellipsometric parameter of every group of pixel are matched, and the nano junction at corresponding pixel points is therefrom extracted
The parameter to be measured of structure film；The parameter value to be measured of the corresponding nano structure membrane of all pixels point finally constitutes entire visual field area
The three-dimensional microstructure of nano structure membrane to be measured in domain.
Nano structure membrane large area, high-resolution, wide visual field, on-line measurement device and measurement side provided by the invention
Method is on the basis of transmission spectra ellipsometer, by having additional wavelength selector in being polarized light path, to realize the company of wavelength
It is continuous to adjust, introduce two step imaging optical path systems, i.e. relay imaging unit and vertical imaging unit in analyzing light path, and by analyzing
Linear array detector in light path is replaced with planar array detector, to collect nano structure membrane to be measured in entire imaging viewing field region
Imaging spectral ellipsometry data.By selecting the lens in appropriate value aperture and enlargement ratio, it can be realized simultaneously width and regard
Field blur-free imaging is measured with high lateral resolution.It is independent by being carried out to each pixel in imaging spectral ellipsometry data
Ellipsometry Measurement can accurately reconstruct nano structure membrane to be measured in the large area region including entire imaging viewing field in real time
Three-dimensional microstructure.Meanwhile measuring device and measuring method provided by the invention are substantially still a kind of measuring method,
Meet optical constant (refractive index n and extinction coefficient k) that nanometer manufacture is especially in extensive nano structure membrane manufacturing process
It is thick with geometric parameter such as characteristic line breadth, line height, side wall angle, period spacing, overlay error and the line side of thickness, nanostructure
The on-line measurement of rugosity and line width roughness, the advantage that large area of the invention, quick, low cost, non-destructive accurately measure,
Online process in the manufacture of scale nanometer is monitored and is had a wide range of applications with optimization control field.
Description of the drawings
Fig. 1 is two steps imaging optical path system imaging principle schematic provided by the invention；
Fig. 2 is that polarization state generates unit when the present invention provides the amplitude ratio angle Ψ and phase angle Δ that measure sample to be tested
(PSG) with the embodiment schematic diagram of Polarization unit (PSA)；
Fig. 3 is that polarization state generates unit (PSG) and polarization state when the present invention provides the full Muller matrix M for measuring sample to be tested
The embodiment schematic diagram of analytic unit (PSA)；
Fig. 4 is the measuring device structure provided by the present invention for measuring sample to be tested amplitude ratio angle Ψ and phase angle Δ
Schematic diagram；
Fig. 5 is the measuring device structural schematic diagram provided by the present invention for measuring the full Muller matrix M of sample to be tested；
Fig. 6 is typical film samples schematic diagram；
Fig. 7 is the typical nanostructure schematic diagram in photoetching process.
Specific implementation mode
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to the accompanying drawings and embodiments, right
The present invention is described in further detail.It should be appreciated that described herein, specific examples are only used to explain the present invention, and does not have to
It is of the invention in limiting.
For ease of description, in combination with ellipsometry method the characteristics of, is divided into two when illustrating specific implementation mode
Divide and carry out, is respectively：(1) imaging spectral ellipsometric data measures part；(2) measurement data analysis part.Wherein DATA REASONING portion
Point, according to the difference of apparatus measures parameter, illustrate the amplitude ratio angle Ψ and phase angle Δ instrument that measure sample to be tested respectively
The specific implementation mode of specific implementation mode and the full Muller matrix M instruments for measuring sample to be tested.
According to the difference of apparatus measures parameter, the polarization state in apparatus of the present invention generates unit and Polarization unit tool
Body can be divided into two kinds of embodiments：(1) the amplitude ratio angle Ψ and phase angle Δ of sample to be tested, embodiment such as Fig. 2 are measured
It is shown.Wherein, polarization state generates unit and is made of the polarizer 1, corresponds to Polarization unit at this time by whirl compensator 2 and inspection
Inclined device 3 forms.It can be also made of the polarizer 1 and whirl compensator 2 in addition, polarization state generates unit, correspond to polarization state point at this time
Analysis unit is made of analyzer 3.It is of equal value that both schemes, which measure sample amplitude ratio angle Ψ and the principle of phase angle Δ,.
(2) the full Muller matrix M of sample to be tested is measured, embodiment is as shown in Figure 3.Wherein, polarization state generates unit by the polarizer 1
It is formed with whirl compensator 2, corresponds to Polarization unit at this time and be made of whirl compensator 3 and analyzer 4, and rotation compensation
The fast axle of device 2 and whirl compensator 3 has 5 with certain rotating ratio synchronous rotary, common rotating ratio:1,5:2 and 5:3.In addition,
Polarization state generates unit and can also be made of the polarizer 1, ferroelectric liquid crystal devices 2, quarter wave plate 3 and ferroelectric liquid crystal devices 4, at this time
Corresponding Polarization unit is made of ferroelectric liquid crystal devices 5, quarter wave plate 6, ferroelectric liquid crystal devices 7 and analyzer 8.4 ferroelectricities
Liquid crystal device can be switched by controlling voltage between 2 kinds of different conditions so that polarization state, which generates unit, can generate 4 kinds
The polarised light of different polarization state, corresponding Polarization unit can analyze the polarization state of 4 kinds of different polarization light, and then obtain
The full Muller matrix of sample to be tested.
(1) imaging spectral ellipsometric data measures
Fig. 4 is the measuring device provided by the present invention for measuring sample to be tested amplitude ratio angle Ψ and phase angle Δ.It is main
To include light source 1, wavelength selector 2, fiber coupler 3, output optical fibre 4, collimation lens 5, the polarizer 6, polarization state generates single
Member 7, is polarized arm 8, specimen rotating holder 9, nano structure membrane 10 to be measured, goniometer 11, front lens 12, rear lens 13, relaying at
As unit 14, goniometer 15, high-NA objective 16, tube lens 17, vertical imaging unit 18, hollow motor 19, phase
Compensator 20, analyzer 21, Polarization unit 22, planar array detector 23, analyzing arm 24, synchronizing device 25, controller 26,
Computer 27.
Light source 1, wavelength selector 2 and fiber coupler 3 are located in same light path, are connected by optical fiber between three, defeated
The one end for going out optical fiber 4 is connected on fiber coupler, and the light beam drawn from the output optical fibre other end is located at the focus position of collimating mirror 5
It sets, the polarizer 6 in collimation lens 5 and polarization state generation unit 7, which is located at, to be polarized in light path, and is fixed on and is polarized on arm 8.It is preceding
Mirror 12 and rear lens 13 are in same light path, and two focal length of lens conjugation put composition relay imaging unit 14.It is polarized 8 He of arm
Relay imaging unit 14 abides by the principle of reflection of light, is symmetrically arranged on goniometer 11 with identical inclination angle, and nano junction to be measured
At the front focal plane of 10 front lens 12 of structure film.
Vertical imaging unit 18 is made of high-NA objective 16 and tube lens 17, wherein vertical imaging unit 18 with
Relay imaging unit 14 is placed on the both sides of goniometer 15 according to the angle that formula (1) describes.In hollow motor 19
Phase compensator 20 and analyzer 21 collectively constitute Polarization unit 22, vertical imaging unit 18, Polarization unit
22 and planar array detector 23 be located in same light path, be fixed on together 24 on analyzing arm with relay imaging unit 14.Face battle array is visited
23 sensitive chip of device is surveyed to be located on the back focal plane of tube lens 17.
Computer 27 is rotated by controller 26 to control hollow motor 19, while operating synchronizing device 25 to capture rotation
The high level signal that motor 19 is sent out carries out the acquisition and storage of data to trigger planar array detector 23.
Fig. 5 is the measuring device provided by the present invention for measuring the full Muller matrix M of sample to be tested.Include mainly light source 1,
Wavelength selector 2, fiber coupler 3, output optical fibre 4, collimation lens 5, the polarizer 6, hollow motor 28, phase compensator 29,
Polarization state generates unit 7, is polarized arm 8, specimen rotating holder 9, nano structure membrane 10 to be measured, goniometer 11, front lens 12, it is rear thoroughly
Mirror 13, relay imaging unit 14, goniometer 15, high-NA objective 16, tube lens 17, vertical imaging unit 18 are hollow
Motor 19, phase compensator 20, analyzer 21, Polarization unit 22, planar array detector 23, analyzing arm 24, synchronizing device
25, controller 26, computer 27, phase compensator 28 and hollow motor 29.
Light source 1, wavelength selector 2 and fiber coupler 3 are located in same light path, are connected by optical fiber between three, defeated
The one end for going out optical fiber 4 is connected on fiber coupler, and the light beam drawn from the output optical fibre other end is located at the focus position of collimating mirror 5
It sets, the polarizer 6 in collimation lens 5 and polarization state generation unit 7, which is located at, to be polarized in light path, and is fixed on and is polarized on arm 8.It is preceding
Mirror 12 and rear lens 13 are in same light path, and two focal length of lens conjugation put composition relay imaging unit 14.It is polarized 8 He of arm
Relay imaging unit 14 abides by the principle of reflection of light, is symmetrically arranged on goniometer 11 with identical inclination angle, and nano junction to be measured
At the front focal plane of 10 front lens 12 of structure film.
Vertical imaging unit 18 is made of high-NA objective 16 and tube lens 17, wherein vertical imaging unit 18 with
Relay imaging unit 14 is placed on the both sides of goniometer 15 according to the angle that formula (1) describes.In hollow motor 19
Phase compensator 20 and analyzer 21 collectively constitute Polarization unit 22, vertical imaging unit 18, Polarization unit
22 and planar array detector 23 be located in same light path, be fixed on together 24 on analyzing arm with relay imaging unit 14.Face battle array is visited
The sensitive chip for surveying device 23 is located on the back focal plane of tube lens 17.
Computer 27 drives phase compensator 29 respectively by controller 26 to control hollow motor 28 and hollow motor 19
With phase compensator 20 with certain rotating ratio synchronous rotary, common rotating ratio has 5:1,5:2 and 5:3.Operate synchronization simultaneously
Device 25 come capture two hollow motors synchronization the positions HOME signal, triggering planar array detector 23 progress data acquisition and deposit
Storage.
In two kinds of instrument specific embodiments provided by the invention, the light source 1 can select xenon source, can also
Select laser light source.
In two kinds of instrument specific embodiments provided by the invention, monochromator, acousto-optic can be selected in the wavelength selector 2
Tunable filter or liquid crystal tunable filter etc. have the relevant device of wavelength selection function.
In two kinds of instrument specific embodiments provided by the invention, the polarizer 6 and analyzer 21 are that can will appoint
Meaning light beam becomes the polarizer of linearly polarized light or the polarization state of detection light.
In two kinds of instrument specific embodiments provided by the invention, the phase compensator 20 and 28 is can be at two
The optics anisotropic device of certain phase-delay difference is generated in mutually perpendicular direction.
In two kinds of instrument specific embodiments provided by the invention, the high-NA image-forming objective lens 16 are unlimited distance light
It learns and designs unstressed half apochromatism of flat field or unstressed flat field apochromatic objective.
In two kinds of instrument specific embodiments provided by the invention, CCD camera may be used in the planar array detector 23
Or CMOS cameras.
Nano structure membrane to be measured is measured using above-mentioned measuring device to obtain its imaging spectral ellipsometry number
According to mainly including the following steps that：
Nano structure membrane 10 to be measured is placed on specimen rotating holder 9 by the 1st step；
2nd step conditioning instrumentation imaging optical path so that planar array detector 23 can obtain the blur-free imaging in sample region to be measured；
The light that 3rd step is sent out from light source 1 after wavelength selector 2 through becoming monochromatic light, and monochromatic light is through 3 He of fiber coupler
Optical fiber 4 is drawn to be introduced into and is polarized 8 one end of arm, after by collimating mirror 5 become collimated light beam, using polarization state generate unit 7 into
It is incident to nano structure membrane 10 to be measured after the modulation of row polarization state；
4th step collimated light beam successively passes through relay imaging unit 14 after 10 surface reflection of nano structure membrane to be measured
It is entered in planar array detector 23 after carrying out polarization state demodulation using Polarization unit 22 with vertical imaging unit 18,
Planar array detector the image collected is eventually transferred in computer 27.Computer is obtained according to planar array detector the image collected
To the corresponding light intensity signal of reflected light, controlling polarization state generation unit by controller 26 can obtain with Polarization unit
The light intensity signal of reflected light under different polarization state；
10 corresponding surface of nano structure membrane to be measured is calculated in the light intensity signal for the reflected light that 5th step is obtained according to the 4th step
Measurement ellipsometric parameter on array detector 23 at each pixel, the corresponding measurement ellipsometric parameter composition of all pixels point entirely regard
The imaging ellipsometry data of sample to be tested in field areas.
Data acquisition principle on planar array detector at each pixel is the same, and can specifically be detected with face battle array
For data acquisition on device at arbitrary m rows and the n-th corresponding pixel of row.
For measuring device shown in Fig. 4, the reflected beams Stokes Vector S corresponding with incident beamout, SinBetween
Relational expression be：
Sout=[MAR(θA)]·[R(-θC)MC(δ)R(θC)]·MS·[R(-θP)MP]·Sin (5)
Wherein MP、MA、MC(δ) and MSRespectively the polarizer 6, analyzer 21, phase compensator 20 and nanostructure to be measured are thin
10 corresponding Muller matrix of film；δ is the corresponding phase-delay quantity of phase compensator；R (α) is that rotation angle is α (α=θP,θA,θC)
Rotation Muller matrix；θPAnd θARespectively (i.e. light transmission axis direction is pressed from both sides with the plane of incidence at the light transmission shaft azimuth of the polarizer and analyzer
Angle), θCFor the phase retardation (i.e. fast axis direction with plane of incidence angle) of phase compensator, and θC=ω t-CS, ω is phase benefit
Repay the rotation angular frequency of device, CSIndicate the fast axle initial orientation angle of phase compensator.Expression formula (5) expansion can be reflected
The corresponding light intensity expression of light beam：
By expression formula (6) it is found that nano structure membrane to be measured corresponds to the arbitrary m rows of planar array detector and the n-th row pixel
It is the cyclical signal changed over time to locate collected light intensity signal, therefore can carry out Fourier analysis, Er Qieyou to it
The harmonic constant of this obtained light intensity signal is the linear letter of corresponding parameter cos2 Ψ, sin2 Ψ cos Δs and sin2 Ψ sin Δs
Number.It follows that after collecting the light intensity signal of the reflected beams, by carrying out Fourier analysis to it, believed by light intensity
Number harmonic constant can obtain the value of cos2 Ψ, sin2 Ψ cos Δs and sin2 Ψ sin Δs, and can further acquire whole
Amplitude ratio angle Ψ (- 180 °≤Ψ≤180 °) in value range and phase angle Δ (0 °≤Ψ≤90 °).It is visited by opposite battle array
Surveying the above-mentioned Fourier analysis of light intensity signal progress collected at device all pixels point can obtain in entire field of view
The imaging ellipsometry data of nano structure membrane to be measured.In addition, in addition to carrying out Fourier to each pixel on planar array detector
Except leaf analysis, can also Fourier analysis be carried out to improve the noise of collected light intensity signal to multiple pixels simultaneously
Than.
For measuring device shown in Fig. 5, the reflected beams Stokes Vector S corresponding with incident beamout, SinBetween
Relational expression be：
Wherein MP, MA, MC1(δ1), MC2(δ2) and MSRespectively the polarizer 5, analyzer 21, polarization state generate unit phase and mend
Repay 10 corresponding Muller matrix of device 28, Polarization unit phase compensator 20 and nano structure membrane to be measured；δ1And δ2Respectively
Unit phase-delay quantity corresponding with Polarization unit phase compensator is generated for polarization state；R (α) is that rotation angle is α (α
=θP,θA,θC1,θC2) rotation Muller matrix；θPAnd θAThe respectively light transmission shaft azimuth of the polarizer and analyzer, θC1And θC2
Respectively polarization state generates the phase retardation of unit and Polarization unit phase compensator, and θC1=ω1t-CS1, θC2
=ω2t-CS2, ω1And ω2For the rotation angular frequency of two phase compensators, CS1And CS2At the beginning of fast axle for two phase compensators
Beginning azimuth.Polarization state generates unit phase compensator and Polarization unit phase compensator in data acquisition
Fast axle is with certain rotating ratio ω1:ω2Synchronous rotary, common rotating ratio have 5:1,5:2 and 5:3.Formula (7) expansion can be obtained
To the corresponding light intensity expression of the reflected beams：
Wherein ck=cos2(δk/ 2), sk=sin2(δk/ 2) and KiIt is intermediate variable, MijFor nano structure membrane to be measured
Corresponding Muller matrix MSIn element (i, j=1,2,3,4；K=1,2).
By the time-domain expression (8) of light intensity signal with (9) it is found that nano structure membrane to be measured corresponds to planar array detector takes up an official post
Collected light intensity signal at m rows and the n-th row pixel of anticipating is the cyclical signal changed over time, thus can to its into
Row Fourier analysis, and the harmonic constant of thus obtained light intensity signal is the linear function of corresponding Muller matrix element.By
This is it is found that after collecting the light intensity signal of the reflected beams, by carrying out Fourier analysis to it, by the humorous of light intensity signal
Wave system number can obtain on planar array detector the Muller matrix element of nano structure membrane to be measured at corresponding pixel points.By right
The light intensity signal collected at planar array detector all pixels point, which carries out above-mentioned Fourier analysis, can obtain entire visual field area
The imaging Muller matrix measurement data of nano structure membrane to be measured in domain.In addition, for isotropism sample to be tested, Muller square
Battle array theoretically should be：
Wherein R is the reflectivity of sample to be tested.Obviously, it when sample to be tested is isotropism sample, is surveyed using shown in Fig. 5
Device is measured after obtaining its Muller matrix, its corresponding amplitude ratio angle Ψ and phase angle Δ can also be acquired.
6th step changes the wavelength X of incident beam using wavelength selector 2, and arm 8 and analyzing are polarized by the adjusting of goniometer 11
Inclination angle between arm 24 (needs to adjust relay imaging unit 14 by goniometer 15 simultaneously with the incidence angle θ for changing incident beam
With the angle theta ' between 18 optical axis of vertical imaging unit), rotation sample stage 9 is to change incident beam and nano structure membrane to be measured
Institute is at azimuth φ between 10；Repeat the step of the 2nd step~the 5th, can obtain under different wave length, incidence angle and azimuth configuration at
As ellipsometry data.
(2) measurement data is analyzed
It is to analyze it after the imaging spectral ellipsometry data for obtaining nano structure membrane to be measured, so as to
The ginsengs to be measured such as optical constant and film thickness, nano structure line width, line height, the side wall angle of sample are extracted from measurement data
Number.Measurement data analysis mainly includes the following steps that：
It is corresponding that 7th step calculates nano structure membrane to be measured under given wavelength X, incidence angle θ and azimuth φ configuration
Theory imaging ellipsometric data；
The calculating of the corresponding theoretical imaging ellipsometric data of nano structure membrane to be measured, may be used not according to the characteristic of sample
Same computational methods.Specifically, when sample is film, can directly be calculated using fresnel formula；And work as sample
For nanostructure when, rigorous couple-wave analysis (RCWA), FInite Element (FEM), boundary element method (BEM) or limited may be used
FD―TD method (FDTD) etc. is calculated, below analytic explanation.
Fig. 6 is a typical film samples, it is the thin film on substrate.The complex refractivity index of wherein basal layer is
N2, the complex refractivity index of film layer is N1, thickness d, N0For the refractive index of film sample surrounding medium.When surrounding medium is sky
When gas, N0=1.The definition of complex refractivity index N is the refractive index and extinction coefficient that N=n-ik, n and k are respectively medium, and i is imaginary number
Unit.Under normal circumstances, the optical constant N of film layer1And its thickness d is parameter to be measured.In Fig. 6, θ0Expression incidence angle (θ=
θ0), θ1For light beam from surrounding medium enter film layer after refraction angle, θ2Enter after basal layer from film layer for light beam
Refraction angle.According to snell law：
N0sinθ0=N1sinθ1=N2sinθ2 (11)
According to fresnel formula can in the hope of light beam at film layer upper surface p light (perpendicular to the electric field component of the plane of incidence)
The corresponding amplitude reflection coefficient r with s light (electric field component for being parallel to the plane of incidence)01,pAnd r01,s：
Similarly, interface p light and s light of the light beam between film layer and basal layer can also be acquired according to fresnel formula
Corresponding amplitude reflection coefficient r12,pAnd r12,s：
After being incident to film sample reflection according to formula (12)-(15) in the hope of light beam, corresponding p light and s light correspond to
Amplitude reflection coefficient rppAnd rss：
The π of wherein β=2 dN1cosθ1/λ.Amplitude ratio angle Ψ and phase angle may further be acquired by formula (16) and (17)
Δ, i.e.,：
By obtained amplitude ratio angle Ψ and phase angle Δ, it is corresponding that sample can further be acquired according to formula (10)
Muller matrix M.
Fig. 7 is the typical cycle nanostructure in a photoetching process, and RCWA methods is selected to calculate its corresponding Muller square
Battle array M, the main step that calculates include：
(i) electromagnetic field expressions of incidence zone and transmission area are acquired by Maxwell equation；
(ii) fourier expansion is carried out to the dielectric constant of grating region and electromagnetic field, then by Maxwell equation or
Helmholtz equation exports coupledwave equation group；
(iii) field boundary condition is used in the up-and-down boundary of grating region, it can by certain matrix operation
Acquire the amplitude coefficient of each level diffracted wave.Cashier can be further calculated according to the amplitude coefficient of obtained Zero-order diffractive wave
The Jones matrix J of rice optical grating construction：
Wherein the left and right sides of Jones matrix J indicates reflection Jones's vector corresponding with incident polarization light beam, E respectivelyp,sPoint
The electric field component of the plane of incidence Biao Shi be parallel and perpendicular to.When fevering sodium effect is not present in measurement process, corresponding Muller square
There are following relational expressions between battle array M and Jones matrix J：
WhereinIndicate Kronecker product, J*For the complex-conjugate matrix of Jones matrix J, A-1For the inverse matrix of matrix A, matrix
A is：
8th step is by the theoretical imaging spectral ellipsometric data that the 7th step is calculated and the ellipse inclined survey of imaging spectral that the 6th step obtains
Each pixel or the corresponding spectroscopic ellipsometry data of every group of pixel are matched in amount data, therefrom extract correspondence
The parameter to be measured of nano structure membrane at pixel.
Nano structure membrane parameter extraction process to be measured is a typical reverse temperature intensity process.The input of the inverse problem
For the imaging spectral ellipsometry data of nano structure membrane to be measured, the parameter value to be measured for nano structure membrane is exported.It is inverse to ask
The solution target of topic is, arbitrary pixel in corresponding imaging spectral ellipsometry data, can find one group of nano structure membrane
Parameter value to be measured so that the spectroscopic ellipsometry data that its theoretical spectral ellipsometric data can be at the best match pixel.Still
With arbitrary m rows on planar array detector and the spectroscopic ellipsometry data instance at the n-th row corresponding pixel points, above-mentioned inverse problem is asked
Solution preocess mathematical linguistics can be expressed as：
Wherein yex(λi, θ, φ) and indicate a wavelength points λ of i-th (i=1,2 ..., N)iUnder the conditions of incidence angle θ, azimuth φ
Corresponding ellipsometry data (can be amplitude ratio angle Ψ and phase angle Δ or Muller matrix element)；ycal(p,λi,θ,
φ) indicate corresponding wavelength λi, theoretical ellipsometric data under the conditions of incidence angle θ and azimuth φ, p is nano structure membrane ginseng to be measured
Array at K dimensional vectors, Ω be parameter value range to be measured,For final parameter extraction value to be measured；δ y indicate ellipsometry
The standard deviation of data；M is total data point number, when measurement parameter is amplitude ratio angle Ψ and phase angle Δ, M=2N, when
When measurement parameter is Muller matrix, M=15N.Such as Levenberg- specifically may be used in solution for formula (22)
The non-linear regression method of Marquardt algorithms etc can also use " a kind of use disclosed in patent document CN102798342A
In the storehouse matching method based on error of fitting interpolation of optical scattering measurement ", or using Chen Xiuguo et al. in " Improved
measurement accuracy in optical scatterometry using correction-based library
" one kind being based on modified storehouse matching method " proposed in search " papers.
To arbitrary pixel solution formula (22) in imaging spectral ellipsometry data, can obtain corresponding at the pixel
Nano structure membrane parameter value to be measured.The parameter value to be measured of the corresponding nano structure membrane of all pixels point, finally constitutes
The three-dimensional microstructure of nano structure membrane to be measured in entire field of view.
The present invention is not limited in above-mentioned specific implementation mode, and persons skilled in the art are according to disclosed by the invention interior
Hold, other a variety of specific implementation modes may be used and implement the present invention.Therefore, every design structure using the present invention and think of
Road does some simple designs changed or change, both falls within the scope of protection of the invention.
Claims (9)
1. a kind of nano structure membrane on-line measurement device, which is characterized in that including being polarized arm (8) and analyzing arm (24) wherein：
Arm (8) and the analyzing arm (24) of being polarized is respectively with thin film planar normal to be measured at identical inclination angle theta；
It is described to be polarized arm (8) and incident light is coaxial, for collimating external light source incident light, collimated light beam is obtained, simultaneously
Polarization state modulation is carried out to incident light, obtains elliptically polarized light；
The analyzing arm (24) is located at light reflecting thin film road to be measured, by relay imaging unit (14), vertical imaging unit
(18) and Polarization unit (22) puts composition successively；Wherein：
The relay imaging unit (14) puts group by front lens (12) and rear lens (13) according to optical axis coincidence, focal length conjugation
At；Its front focus is overlapped with thin film center to be measured；
The vertical imaging unit (18) is put by high-NA objective (16) and tube lens (17) common optical axis conjugation；Lens barrel
The back focal plane of lens (17) is equipped with the sensitive chip of planar array detector (23), for realizing blur-free imaging；
Relay imaging unit (14) back focal length is conjugated with the front focal length of vertical imaging unit (18), and optical axis between the two
Angle theta ' meet formulaWherein θ is incidence angle of the external light source relative to film to be measured, f1And f2Respectively
The front focal plane focal length of the back focal plane focal length and rear lens (13) of corresponding front lens (12)；Vertical imaging unit (18) and polarization state point
Analysis unit (22) is put using common optical axis；To realize blur-free imaging and the measurement of instrument；
The Polarization unit (22) is used to carry out Polarization to the light beam that vertical imaging unit (18) is emitted, to
Measure the ellipsometric parameter of sample to be tested.
2. on-line measurement device as described in claim 1, which is characterized in that it is described be polarized arm include collimation lens (5) and partially
Polarization state generates unit PSG (7), and the two is arranged with optical axis, and the collimation lens is sent for being collimated to external light source incidence light
Enter polarization state and generates the modulation that unit PSG (7) realizes polarization state.
3. on-line measurement device as claimed in claim 2, which is characterized in that the polarization state generates unit PSG (7) and includes
Inclined device (6), corresponds to Polarization unit (22) and is made of the phase compensator (20) and analyzer (21) rotated at this time；
4. on-line measurement device as claimed in claim 2, which is characterized in that the polarization state generates unit PSG (7) by being polarized
Device (6) and the phase compensator (28) of rotation composition, correspond to phase of the Polarization unit by analyzer (21) and rotation at this time
Position compensator (20) forms.
5. on-line measurement device as claimed in claim 2, which is characterized in that the polarization state generates unit (7) by sequentially total
The polarizer, preceding ferroelectric liquid crystal devices, quarter wave plate and rear ferroelectric liquid crystal devices (4) composition of optical axis setting, correspond to polarization state at this time
Analytic unit (22) by ferroelectric liquid crystal devices (5), quarter wave plate (6), ferroelectric liquid crystal devices (7) and analyzer (8) common optical axis successively
It puts；By controlling the voltage direction of 4 ferroelectric liquid crystal devices, 2 kinds of different conditions of ferroelectric phase and paraelectric phase are generated, to generate
The polarised light of 4 kinds of different polarization states obtains all 16 members in the Muller matrix M of sample to be tested through Polarization unit
Element.
6. on-line measurement device as claimed in claim 2, which is characterized in that the polarization state generates unit (7) by the polarizer
(6) with the phase compensator (28) of rotation composition, correspond at this time Polarization unit by the phase compensator (20) that rotates and
Analyzer (21) forms, and the fast axle of phase compensator (28) and phase compensator (20) is with certain rotating ratio synchronous rotary；
Rotating ratio is preferably 5:1,5:2 and 5:3.
7. on-line measurement device as described in claim 1, which is characterized in that the external light source includes light source (1), wavelength choosing
Select device (2), fiber coupler (3) and output optical fibre (4)；The light that light source (1) generates is changed into Single wavelength through wavelength selector (2)
Light, it is the output end of external light source to send output optical fibre (4), output optical fibre (4) through fiber coupler (3).
8. on-line measurement device as claimed in claim 4, which is characterized in that further include control system, the control system with it is same
Step setting is connected, during the synchronizing device and being located at is polarized in arm (8) second in the first hollow motor (29) and analyzing arm (24)
Empty motor (19) is connected, and for controlling the phase compensator in two-arm with certain rotating ratio synchronous rotary, and then realizes polarization
The modulation and demodulation of state.
9. a kind of nano structure membrane On-line Measuring Method, which is characterized in that include the following steps：
(1) nano structure membrane to be measured is placed on sample stage；
(2) imaging optical path is adjusted, the blur-free imaging in sample region to be measured is obtained on planar array detector；
(3) by Single wavelength collimated light beam after polarization state generation unit is modulated, acquisition elliptically polarized light is projected to be measured
Nano structure membrane surface；
(4) it after carrying out polarization state demodulation to nano structure membrane surface reflection to be measured, enters in planar array detector, obtains not
With reflective light intensity signal under polarization state；
(5) the reflective light intensity signal obtained according to (4) step is calculated nano structure membrane to be measured and corresponds on planar array detector
Measurement ellipsometric parameter at each pixel, the corresponding measurement ellipsometric parameter of all pixels point constitute to be measured in entire field of view
The imaging ellipsometry data of sample
(6) change the wavelength X of incident beam and the incidence angle θ of incident beam, rotation sample stage is to change incident beam and wait for
Institute is at azimuth φ between surveying nano structure membrane；(2) step~the (5) step is repeated, different wave length, incidence can be calculated
Actual imaging ellipsometric data under angle and azimuth configuration；
(7) under given wavelength X, incidence angle θ and azimuth φ configuration, calculate nano structure membrane to be measured it is corresponding it is theoretical at
It is poor using rigorous couple-wave analysis (RCWA), FInite Element (FEM), boundary element method (BEM) or finite time-domain as ellipsometric data
Point-score (FDTD) is calculated；
(8) it calculates actually measuring arbitrary pixel on obtained imaging spectral ellipsometric data, obtains at the pixel pair
The parameter value to be measured for the nanostructure answered；The parameter value to be measured for completing the corresponding nanostructure of all pixels point solves, final
The three-dimensional microstructure of nanostructure to be measured in entire field of view.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610921773.2A CN106517086B (en) | 2016-10-21 | 2016-10-21 | A kind of large area high-resolution wide visual field on-line measurement device and its measurement method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610921773.2A CN106517086B (en) | 2016-10-21 | 2016-10-21 | A kind of large area high-resolution wide visual field on-line measurement device and its measurement method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106517086A CN106517086A (en) | 2017-03-22 |
| CN106517086B true CN106517086B (en) | 2018-10-30 |
Family
ID=58291880
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610921773.2A Active CN106517086B (en) | 2016-10-21 | 2016-10-21 | A kind of large area high-resolution wide visual field on-line measurement device and its measurement method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106517086B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11428630B2 (en) * | 2019-12-02 | 2022-08-30 | Nankai University | System and method for determining second order nonlinear susceptibility of material |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109405749B (en) * | 2018-11-19 | 2024-03-26 | 清华大学深圳研究生院 | Laser imaging ranging method and system |
| WO2020215199A1 (en) * | 2019-04-23 | 2020-10-29 | 合刃科技（深圳）有限公司 | Surface defect detection system and method |
| KR102802193B1 (en) * | 2019-07-22 | 2025-04-30 | 삼성전자주식회사 | Inspection method based on IE(Imaging Ellipsometry), and method for fabricating semiconductor device using the inspection method |
| CN110440926B (en) * | 2019-08-13 | 2020-11-13 | 北京环境特性研究所 | Time-sharing infrared polarization imaging device and method for dynamic target measurement |
| CN112432908A (en) * | 2019-08-25 | 2021-03-02 | 南京理工大学 | Laboratory simulation sea surface oil spill detection method based on polarization characteristics |
| CN110596011B (en) | 2019-08-26 | 2020-12-29 | 华中科技大学 | A kind of material dielectric tensor measurement method |
| CN111799189A (en) * | 2020-07-11 | 2020-10-20 | 天津大学 | Online optical measurement system and method for influence of rotation centrifugal quantity on crystalline state of spin-coated film |
| CN112540044A (en) * | 2020-07-14 | 2021-03-23 | 深圳中科飞测科技股份有限公司 | Elliptical polarization measuring equipment and focusing method and measuring method thereof |
| CN112362592A (en) * | 2020-10-30 | 2021-02-12 | 华中科技大学 | Polarization reflection measurement system and detection method thereof |
| CN112880574B (en) * | 2021-01-08 | 2023-02-03 | 上海精测半导体技术有限公司 | Film thickness measuring method |
| CN114754705B (en) * | 2022-04-11 | 2023-05-05 | 华侨大学 | Vertical scanning white light interference spectrum auxiliary Mueller matrix ellipsometry system and method |
| TWI804401B (en) | 2022-07-28 | 2023-06-01 | 國立成功大學 | Optical measurement system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5076696A (en) * | 1989-03-16 | 1991-12-31 | The Johns Hopkins University | Dynamic imaging microellipsometry |
| US5333052A (en) * | 1990-11-27 | 1994-07-26 | Orbotech Ltd. | Method and apparatus for automatic optical inspection |
| JPH11183132A (en) * | 1997-12-25 | 1999-07-09 | Jasco Corp | Optical system of particle measuring device |
| CN1699967A (en) * | 2004-05-18 | 2005-11-23 | 中国科学院力学研究所 | Incident angle scanning ellipsometry imaging measurement method and device |
| CN101398293A (en) * | 1998-12-02 | 2009-04-01 | 西门子公司 | Measurement system and method for measuring critical dimensions using ellipsometry |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101881599B (en) * | 2010-07-12 | 2012-01-25 | 华中科技大学 | Method and device for measuring three-dimensional topography of nano structure |
| CN103134592B (en) * | 2013-01-31 | 2015-11-04 | 华中科技大学 | A transmission type full Muller matrix spectroscopic ellipsometer and its measurement method |
| CN104501738B (en) * | 2014-12-31 | 2017-08-11 | 华中科技大学 | The method for fast measuring and device of large area scattered field under nanoscale |
-
2016
- 2016-10-21 CN CN201610921773.2A patent/CN106517086B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5076696A (en) * | 1989-03-16 | 1991-12-31 | The Johns Hopkins University | Dynamic imaging microellipsometry |
| US5333052A (en) * | 1990-11-27 | 1994-07-26 | Orbotech Ltd. | Method and apparatus for automatic optical inspection |
| JPH11183132A (en) * | 1997-12-25 | 1999-07-09 | Jasco Corp | Optical system of particle measuring device |
| CN101398293A (en) * | 1998-12-02 | 2009-04-01 | 西门子公司 | Measurement system and method for measuring critical dimensions using ellipsometry |
| CN1699967A (en) * | 2004-05-18 | 2005-11-23 | 中国科学院力学研究所 | Incident angle scanning ellipsometry imaging measurement method and device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11428630B2 (en) * | 2019-12-02 | 2022-08-30 | Nankai University | System and method for determining second order nonlinear susceptibility of material |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106517086A (en) | 2017-03-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106517086B (en) | A kind of large area high-resolution wide visual field on-line measurement device and its measurement method | |
| CN106595521B (en) | vertical objective lens type Mueller matrix imaging ellipsometer based on liquid crystal phase modulation | |
| Shimizu et al. | An insight into optical metrology in manufacturing | |
| Garcia-Caurel et al. | Application of spectroscopic ellipsometry and Mueller ellipsometry to optical characterization | |
| US7230717B2 (en) | Pixelated phase-mask interferometer | |
| US7777895B2 (en) | Linear-carrier phase-mask interferometer | |
| CN110987817B (en) | Ellipsometer integrating dark field observation based on large-numerical-aperture objective lens and measurement method | |
| US7177030B2 (en) | Determination of thin film topography | |
| Garcia-Caurel et al. | Advanced Mueller ellipsometry instrumentation and data analysis | |
| US6721094B1 (en) | Long working distance interference microscope | |
| CN113777049B (en) | Angle-resolved snapshot ellipsometer and measuring system and method thereof | |
| US5784163A (en) | Optical differential profile measurement apparatus and process | |
| US20100309476A1 (en) | Linear-carrier phase-mask interferometer | |
| US10054423B2 (en) | Optical method and system for critical dimensions and thickness characterization | |
| CN101666630B (en) | A Precision Wafer Inspection Method and Device Based on Parallel Flat Crystal Split Polarized Beam and Phase Shift Interferometry | |
| CN104482878A (en) | Large-area online measurement device and method for geometrical parameters of nano-structure | |
| JP2013117533A (en) | Low coherence interferometric system for phase stepping shearography combined with 3d surface shape measurement | |
| CN1187600C (en) | Apparatus and method for measuring equivalent refraction power of optical film and physical thickness | |
| US6693711B1 (en) | Ellipsometer using radial symmetry | |
| CN100492179C (en) | Interferometer | |
| CN109341554B (en) | Device and method for measuring film thickness | |
| CN107923735B (en) | Method and device for deducing the topography of an object surface | |
| Jung et al. | A breakthrough on throughput and accuracy limitation in ellipsometry using self-interference holographic analysis | |
| US11668645B2 (en) | Spectroscopic ellipsometry system for thin film imaging | |
| Kim et al. | LASIE: large area spectroscopic imaging ellipsometry for characterizing multi-layered film structures |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | 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 |