EP1145303A1 - Dispositif et procede de controle optique de processus de fabrication de surfaces microstructurees dans la production de semi-conducteurs - Google Patents

Dispositif et procede de controle optique de processus de fabrication de surfaces microstructurees dans la production de semi-conducteurs

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Publication number
EP1145303A1
EP1145303A1 EP99961050A EP99961050A EP1145303A1 EP 1145303 A1 EP1145303 A1 EP 1145303A1 EP 99961050 A EP99961050 A EP 99961050A EP 99961050 A EP99961050 A EP 99961050A EP 1145303 A1 EP1145303 A1 EP 1145303A1
Authority
EP
European Patent Office
Prior art keywords
reference signatures
measuring
classification
diffraction
production
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.)
Withdrawn
Application number
EP99961050A
Other languages
German (de)
English (en)
Inventor
Norbert Benesch
Claus Schneider
Lothar Pfitzner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Original Assignee
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Semiconductor 300 GmbH and Co KG
Infineon Technologies SC300 GmbH and Co KG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE19922614A external-priority patent/DE19922614A1/de
Application filed by Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV, Semiconductor 300 GmbH and Co KG, Infineon Technologies SC300 GmbH and Co KG filed Critical Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Publication of EP1145303A1 publication Critical patent/EP1145303A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
    • H01L22/30—Structural arrangements specially adapted for testing or measuring during manufacture or treatment, or specially adapted for reliability measurements
    • H01L22/34—Circuits for electrically characterising or monitoring manufacturing processes, e. g. whole test die, wafers filled with test structures, on-board-devices incorporated on each die, process control monitors or pad structures thereof, devices in scribe line
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/21—Polarisation-affecting 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
    • G03F7/70491—Information management, e.g. software; Active and passive control, e.g. details of controlling exposure processes or exposure tool monitoring processes
    • 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
    • G03F7/70605—Workpiece metrology
    • G03F7/70616—Monitoring the printed patterns
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
    • H01L22/10—Measuring as part of the manufacturing process
    • H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions

Definitions

  • the invention relates to a method for the optical control of manufacturing processes of finely structured surfaces in semiconductor production and an apparatus for carrying out the method.
  • a comparison is made with existing diffraction patterns of tested structures.
  • semiconductor manufacturing often have to during the manufacturing process
  • Line widths and profiles of structured layers can be checked. Exact compliance with the specifications for the line width is of crucial importance for the functionality of the product. In addition, other structural parameters such as B. trench depth or side slopes of great importance. Suitable measuring devices are required to check these production parameters on lithography masks, semiconductor wafers or other finely structured surfaces.
  • the measuring area to be examined is illuminated in this method and the surface properties of the measuring area are inferred from the characteristics of the reflected light. If there are periodic structures on the substrate, diffraction and interference effects occur when the light wavelength is selected, which prevent measurement in conventional optical devices, but are explicitly recorded and evaluated in the scattered light measurement or diffraction measurement, since they are characteristic of the structure sizes . With the help of complex model calculations, it is already possible to determine different structure sizes such as line width, bevel or line height by means of scattered light measurement.
  • the reflection of coherent light on periodic structures called amplitudes or
  • Phase grating causes the formation of diffraction and interference effects. If the wavelength of the light used is at least longer than half the grating period, further higher-order diffraction maxima arise in addition to the directly reflected 0th order beam.
  • the position or the angle ⁇ "of the nth diffraction order depends only on the angle of incidence 6>, on the grating period g and on the wavelength:
  • the intensities and the phases of the diffraction orders depend on the properties of the incident beam (angle, Polarization, wavelength), on the examined lattice structure (lattice periods, line width, line height, layer structure, edge rounding, roughness) and on the material properties of the substrate (refractive index, absorption index).
  • the position of the diffraction maxima is only influenced by the angle of incidence, the grating period and the wavelength. If these variables are constant, the other grating parameters can be inferred from the intensity evaluation of the locally fixed diffraction orders. Because of the many grid influencing variables, however, a clear determination of the grid parameters is only possible if a sufficient number of intensity measurement values are available for the measurement point under investigation. The determination of lattice parameters by comparing the measured
  • Diffraction patterns with reference diffraction patterns which were calculated with enormous effort from the circuit layout, have not yet been satisfactorily achieved in the experimental stage, namely only in the case of exclusively parallel lines.
  • Measuring devices for measuring the diffraction patterns according to the prior art are disclosed, for example, in DE 198 24 624 and US 5,703,692. These devices are used with great effort to determine lattice parameters on strictly periodic structures in the production of DRAMs by using the following.
  • a geometrically simple test structure consisting of parallel strips is applied to a wafer. Only their diffraction pattern is then measured and compared with slightly varied reference spectra of the geometrically simple test structure. The lattice parameters of the test structure result from this comparison. The lattice parameters of the DRAM circuits are inferred from these. This conclusion cannot take into account, for example, systematic errors of the lithography machine or an uneven plasma when producing a layer or a speck of dust under the wafer.
  • the invention has for its object to provide an inexpensive and non-destructive method and a device for the optical control of manufacturing processes of finely structured surfaces in semiconductor manufacturing.
  • the use of the method should significantly reduce the device costs, enable in-situ or in-line use and accelerate the measurement and the evaluation of measurement data considerably. Description of the invention
  • the object is achieved by the features of the independent method claim.
  • a device for performing the method is proposed in the independent device claim.
  • the preferred embodiments are the subject of the dependent claims.
  • the classification for checking the semiconductor production during production is carried out as follows. In a preliminary run, a sufficiently large number of the structures to be examined (prototypes with typical production deviations) are measured, for example with the measuring device proposed below, and thus diffraction and / or scattered light images (signatures) are recorded. A number of reference signatures are thus obtained.
  • the samples are examined with a measuring device according to the state of the art, which delivers absolute measured values (e.g. electron microscope).
  • a database which contains the classification of the reference signatures and which enables an assignment of defective parts to the diffraction / scattered light images of the surfaces of samples from production (measurement signatures).
  • a classifying system for example a neural network capable of learning, can now be trained and in the future it can make a good / bad classification itself.
  • the measurements with the electron microscope can then be omitted. Finer divisions into several classes (e.g. direction of the deviations) can also be carried out.
  • the effects of deviations from different parameters can be separated and also integrated into the classification model (the database only has to be large enough for this, e.g. a few 100 samples). This method can be used to examine samples that are difficult to model due to their complexity.
  • This product detection / process step assignment can be used with diffraction analysis not only for periodic structures. Even with general non-periodic (logic) structures, characteristic intensity profiles can occur and enable classification. This extension to non-periodic structures is also possible for the classification of parameter deviations.
  • the described method is particularly suitable for the continuous control of regular structures, e.g. B. of memory elements, which for the most part have symmetrical lattice structures. While the previous methods with numerical Simulations are mainly suitable for simple test structures, the concept proposed here can also be used directly for complex product structures.
  • a classifying system capable of learning e.g. a neural network or fuzzy logic.
  • the intensity profiles are compared with curve profiles of specified samples (prototypes).
  • a learning system e.g. B. a neural network
  • a classification or classification of the relevant sample surface is made (z. B. good / bad).
  • the neural network was trained with a sufficient number of sample structures (prototypes). After a defective structure has been identified, it can be examined in detail using the complex methods of the prior art. The great advantage of this process is its simplicity. There is no need for a highly skilled professional whose job is to model the sample surface as accurately as possible and to predict the stray light and diffraction effects in order to obtain an absolute reading for one or more grating parameters.
  • a faulty adjustment of the sample can be recognized as a further application of the present invention.
  • An unintentional tilting or twisting of the sample during the measurement represents a change in the angle of incidence of light and leads u. U. to significant deviations in the intensity curves.
  • Such random tiltings are also included in the training data for a classifying neural network, which originate from real tests, so that the system automatically takes such effects into account and the design effort to avoid and detect such tiltings can be kept relatively small.
  • the intensities of the higher order diffraction maxima can also be used for correct alignment of the disk.
  • the diffraction orders on the right and left of the direct reflection have different intensities, if the grating vector describing the periodicity of the structures is not in the plane of incidence of the light beam or the sample is twisted. A very simple and sensitive means is thus obtained for determining a rotation of the disk, which has an effect on the intensity profiles to be measured and can thus falsify the measurement result for the structure sizes.
  • Parameter combinations simulated and the resulting intensity curves z. B. be entered in a table.
  • the back calculation then essentially consists of a comparison of the table curves with the curve currently measured. In the case of complex lattice structures, these preliminary simulations can become very extensive / complex and can take days or weeks.
  • the measurement values available with it depend on the structure parameters (line width / layer thickness etc.) in a complex manner. Absolute structure sizes are therefore difficult to determine, but a simple distinction between different structures is possible. Regardless of the actual measurement principle, the basis of the method is the generation of measurement signatures that can be clearly assigned to different grid parameters.
  • a measurement setup for generating polarization-dependent signatures is described below.
  • a light source provides coherent, linearly polarized light of one wavelength.
  • unpolarized light can be linearly polarized by appropriate polarizers.
  • several beams of different wavelengths can be combined into one beam in order to obtain a larger number of bending maxima.
  • the coherent light can also come from a spectral light source (for example a xenon lamp), with different wavelength ranges being extracted with the aid of a filter.
  • the evaluation of the light intensity reflected from the surface which is described below, can thus also be carried out as a function of the wavelength. With the help of the additional parameter, the measuring accuracy and the sensitivity of the method can be increased.
  • a suitable optical element e.g. a ⁇ / 2 plate
  • an electro-optical element can be used to rotate the polarization, or the linearly polarized light source (the laser) is rotated itself.
  • the beam is guided with the help of lenses, mirrors and prisms, the exact arrangement of which does not change the underlying measuring principle. However, they have to
  • the mirrors, prisms or panes can be arranged in any order between the light source, ⁇ / 2 plate and the sample to be examined. It is crucial that a linearly polarized light beam hits the sample surface, the polarization angle of which is varied between 0 ° and 180 °. Alternatively, another angle range between 0 ° and 360 ° can be selected. However, angles above 180 ° do not give fundamentally new information, but represent a repetition of the measurement between 0 ° and 180 °.
  • the measurement method can also be carried out with elliptically polarized light.
  • the ⁇ / 2 plate specifies the azimuth angle (polarization angle), which determines the main axis of the elliptically polarized light.
  • a suitable optical element e.g. a ⁇ / 4 plate
  • the required elliptical polarization arises from linearly polarized light.
  • the noise of the light source z. B. with a photodiode the intensity of a with a beam splitter (z. B. prism or beam plate) decoupled reference beam measured.
  • an angle of incidence suitable for the respective sample is realized (see above for beam guidance). This constant angle of incidence of the light beam on the sample represents an important difference to similar measuring devices previously presented and considerably simplifies the measurement setup.
  • the light beam With a diameter of approx.0.5 mm, the light beam generally hits to several thousand individual structures, so that the measurement result represents an average of the relevant lattice parameters. If desired, the light beam can be expanded using optics to increase the number of individual structures viewed simultaneously. Non-periodic structures may also be recorded. In the case of largely non-periodic structures, the measurement method provides information about the roughness or the average surface quality of the sample.
  • the light steel can also be focused to cover only a few individual structures if the area of periodic structures is small or because the properties of these individual structures are of particular interest. With the help of a traversing table, different measuring points can be approached on a larger sample surface (mapping). Alternatively, the measuring unit can also be moved and positioned.
  • the grating sizes determine the light distribution from the reflection point.
  • only the intensity of the directly reflected beam as a function of the polarization angle is measured with a photodiode.
  • the reflected beam can in turn be examined by a changeable polarizer (analyzer) at specific polarization angles.
  • mirrors and prisms can be used for beam guidance and beam deflection without affecting the measuring principle. If higher diffraction orders occur, they can also be measured with adjustable photodiodes.
  • One or more curves are obtained for each measuring point, which are used for the classification or also for the absolute determination of a lattice parameter.
  • Lattice parameters are lattice periods, line widths, trench depths, layer thicknesses (also transparent multilayer systems), side wall bevels, rounded edges and surface roughness and material properties (e.g. refractive index).
  • the sample surface can be covered by metals (e.g. aluminum), semiconductors (e.g. polysilicon) or non-metals (e.g. paints).
  • the field of application of the measuring principle or the possible size of the fine surface structures depends on the wavelength of the electromagnetic used Radiation from: The structure sizes should coincide with the wavelength in the order of magnitude.
  • spatially resolved measuring systems e.g. a CCD camera (possibly with a screen in between) can be used for intensity detection. Because of its simple structure with fixed components and the
  • the proposed structure is suitable for integration as an in-situ or in-line device.
  • the result of the measurement is the intensity curves of the diffraction orders (in the simplest case only the 0th diffraction order) depending on the polarization angle between 0 ° and 180 °.
  • the grating vector indicating the direction of the periodicity must not lie in the plane of incidence of the light beam in order for conical diffraction to occur.
  • the application of the method according to the invention is not limited to the variation of the polarization of the light beam used for the measurement.
  • the variation of the angle of incidence (perpendicular and / or azimuthal angle) of the light beam onto the sample is equally suitable for producing different diffraction images.
  • a device for varying the angle of incidence can e.g. look like this.
  • the measuring arrangement as in DE 198 24 624 A1 can be used.
  • the beam splitter is replaced by an electrically controlled rotating mirror.
  • the electrically controlled rotating mirror (so-called galvanometer scanner) is used in conjunction with a fixed, non-planar mirror surface in order to vary the angle of incidence of the measuring beam for a 2 ⁇ diffraction analysis of a fixed measuring point.
  • galvanometer scanner is used in conjunction with a fixed, non-planar mirror surface in order to vary the angle of incidence of the measuring beam for a 2 ⁇ diffraction analysis of a fixed measuring point.
  • Such an arrangement enables large angular positions to be approached within milliseconds with an accuracy of a few ⁇ rad.
  • the variation of the angle of incidence can thus be carried out within a few tenths of a second.
  • only a robust, movable component (galvanometer scanner) is required to generate different angles of incidence, thus reducing the susceptibility to faults.
  • the two first order diffraction maxima with conical diffraction have the same intensity only at a certain angle of rotation of the disk on the measuring station. This provides a simple way of precisely adjusting the angle of rotation that influences the intensity profiles.
  • the intensity curves can be used conventionally with the help of a model for determining absolute grating sizes by parameter regression.
  • FIG. 1 is a schematic diagram of an apparatus according to the invention.
  • FIG. 2 shows the construction of a device for measuring signatures within the implementation of the device from FIG. 1 in an embodiment in which the polarization of the light used for the measurement is varied;
  • FIG. 4 shows a flowchart of the method according to the invention in a further embodiment
  • FIG. 5 shows a flow chart of the use of the method according to the invention
  • the device 10 shows a device 10 for monitoring manufacturing processes of finely structured surfaces in semiconductor manufacturing according to the present invention.
  • the device 10 consists of a device for providing 12
  • Reference signatures of finely structured surfaces a device for measuring 14 at least one signature of the sample surface to be checked, a module for comparing 16 the measured signature with the reference signatures and a module for classifying 18 parameters of the sample surface based on the comparison results.
  • the device for providing 12 reference signatures is designed to carry out a measurement of the reference signatures by measuring the spatial and / or intensity distribution of diffraction images on qualitatively specified production prototypes.
  • Device 10 is integrated in a semiconductor production line and enables in-situ and in-line production monitoring.
  • Production prototypes with the Measure device for measurement 14 and a signature of the sample surface is obtained from each production prototype. Then the production prototypes are quantitatively measured quantitatively and qualitatively specified by analysis with other methods. This qualitative specification encompasses a predetermined classification range with very good, good, still usable, inadequate and very bad classes.
  • the reference signatures are transmitted via connection 20 to the device for providing 12 reference signatures. The signatures, the classifications and the parameters are assigned to one another and stored in the device for the provision 12.
  • the device 10 is now prepared for the control of manufacturing processes of finely structured surfaces in semiconductor manufacturing.
  • Production processes are now checked by measuring the samples to be checked in the device for measurement 14 and measuring a signature of the sample surface to be checked in each case.
  • the signature of a sample is transmitted via connection 22 and reference signatures via connection 24 to the module for comparison 16 of the measured signature with the reference signatures and compared with one another in the module for comparison 16. Results of this comparison of the signatures are forwarded to the module for classification 18 of parameters of the sample surface via connection 26.
  • the module for classification 18 receives classification data and parameters of the reference samples from the device for providing 12 via connection 28, which parameters are assigned to those reference signatures which have been found to be relevant in the comparison.
  • the module for classification 18 uses this data to classify the currently measured sample surface and determines its absolute profile parameters with the aid of a diffraction simulator.
  • FIG. 2 shows the construction of a device for measuring signatures 14 within the device 10 from FIG. 1 in an embodiment in which the polarization of the light used for the measurement is varied.
  • the device for measuring polarization-dependent signatures 30 has a light source 32 which supplies linearly polarized light of a wavelength coherent with beam 33.
  • unpolarized light can be linearly polarized by appropriate polarizers.
  • a polarizer 34 for example a ⁇ / 2 plate
  • an electro-optical element can be used to rotate the polarization, or the linearly polarized light source (the laser) is rotated itself.
  • a linearly or elliptically polarized light beam 36 strikes the surface of the sample 40, whose polarization angle (azimuth) is preferably varied between 0 ° and 180 °.
  • another angle range between 0 ° and 360 ° can be selected or the measurement can be repeated with other angles in order to increase the measuring accuracy.
  • detector 42 e.g. B. a photodiode
  • the intensity of a with a beam splitter 44 z. B. prism or beam plate
  • Reference beam 46 measured.
  • an adjustable beam deflection 48 which is fixed during the measurement, an angle of incidence suitable for the respective sample 40 is selected.
  • This constant angle of incidence of the light beam 36 on the sample represents a simplification compared to those measuring devices which measure a signature as a function of the angle of incidence.
  • a traversing table 50 different measuring points can be approached on a larger sample surface.
  • the grating sizes determine the light distribution from the reflection point.
  • a detector 52 e.g. a photodiode
  • only the intensity of the directly reflected beam 54 (reflex) is measured as a function of the polarization angle. If higher diffraction orders occur, secondary reflections 56, 58, these can also be adjusted with adjustable detectors 60, e.g. Photodiodes or a CCD camera can be measured.
  • the evaluation of the measurement data and the control of the system take place with a computer system connected to the individual device parts, which likewise contains the classification module, preferably the adaptive system, consisting of a neural network. If, according to the prior art, a physical model is used to simulate the diffraction effects, the intensity curves measured with the arrangement can also be used to calculate absolute sample data, in particular profile parameters.
  • the device for measuring a polarization-dependent measurement is preferably present
  • Signature 30 consisting of a coherent electromagnetic radiation source 32, a device for the continuous or small-scale rotation of the polarization 34 of the electromagnetic radiation and at least one electromagnetic radiation detector 52, 60, wherein coherent electromagnetic radiation strikes a finely structured sample surface and the location at a fixed angle of incidence and / or intensity distribution of the diffraction image generated by the reflection of the radiation on the surface is measured with at least one radiation detector 52, 60, as a function of the polarization of the illuminating radiation 36.
  • the illuminating electromagnetic radiation is either linearly or elliptically polarized. Your Wavelength is in the range of the structure sizes of the structures on the finely structured surface and comprises several wavelengths or wavelength ranges.
  • the measurement is carried out either depending on the wavelengths or wavelength ranges in succession or with all wavelengths or wavelength ranges simultaneously.
  • the coherent light advantageously comes from a spectral lamp and the various wavelength ranges are extracted with a filter.
  • the device for the continuous or small-scale rotation of the polarization of the electromagnetic radiation consists of a ⁇ / 2 plate or two ⁇ / 4 plates or an electro-optical element or a device for mechanical rotation of the light source itself.
  • the sample with the finely structured surface is preferably fixed on a traversing table or the entire measuring device is moved relative to the sample and measurements of the spatial and / or intensity distributions of diffraction images are carried out on different areas of the sample surface.
  • the electromagnetic radiation reflected by the finely structured surface is also advantageously examined as a function of its polarization.
  • FIG. 3 shows a flowchart 70 of the method according to the invention for checking manufacturing processes of finely structured surfaces in semiconductor manufacturing.
  • the method consists of the steps of providing reference signatures 72 of finely structured surfaces; Measurement of at least one signature 74 of a sample surface to be checked; Comparison 76 of the measured signature with the reference signatures; and classification 78 of parameters of the sample surface based on the comparison results, the provision of the reference signatures 72 comprising the step of measuring the location and / or intensity distribution of diffraction images on qualitatively specified production prototypes.
  • the signatures are preferably generated optically by measuring the diffraction and / or scattering of electromagnetic radiation on the finely structured surfaces.
  • the comparison of the signature of the sample surface with the reference signatures and their classification are carried out with the help of an adaptive neural network and / or fuzzy logic.
  • the signatures are generated by measuring the intensity distribution of diffraction and / or scattered light images with variation of at least one from the group consisting of polarization, angle of incidence and wavelength of the electromagnetic radiation.
  • the classification of the sample surface consists of a division into good or bad and / or a division into finer graded quality classes and / or the classification of certain production defects.
  • the method is advantageously used to control the production of periodic memory element structures and / or non-periodic logic structures.
  • the provision of the reference signatures comprises the creation of a classification system with an assignment of a classification of the qualitatively specified production prototypes to the measurement data of the reference signatures on the same production prototypes.
  • the provision of reference signatures comprises different products and the classification of parameters of the sample surface includes the identification of the product of the sample.
  • the provision of reference signatures preferably comprises different adjustments of the same production prototypes, and the classification of parameters of the sample surface comprises an incorrect adjustment of the sample.
  • the method according to the invention is represented by a flow chart.
  • the process steps are divided into process sections preliminary run 100 and
  • Production process section 200 divided.
  • the process section preliminary run 100 contains the process step provision of reference signatures and describes them in substeps.
  • advance 100 (teaching in the system)
  • a sufficiently large number of the structures to be examined are measured by measuring the location and / or intensity distribution of diffraction patterns on qualitatively specified production prototypes, 101.
  • a number of reference signatures 103 are obtained
  • the samples are examined 102 with a measuring device according to the state of the art, which delivers absolute measured values 104 (eg electron microscope).
  • the reference signatures can thus be assigned to the absolute measured values of these samples (production prototypes).
  • This provides a database that enables the assignment of defective parts to the diffraction / scattered light images of the surfaces of samples from production (measurement signatures).
  • a neural network will be trained 105 and make a good / bad classification in the future.
  • This provides reference signatures for finely structured surfaces for the production process section 200.
  • At least one signature of a sample surface to be checked is first measured in 201 by measuring the diffraction and / or scatter of electromagnetic radiation on the finely structured surfaces.
  • the signatures are obtained by measuring the intensity distribution of Diffraction and / or scattered light images generated with variation of at least one from the group consisting of polarization, angle of incidence and wavelength of the electromagnetic radiation.
  • the measured signature is then compared with the reference signatures in 202.
  • the similarity of the signature to reference signatures is evaluated and at least one reference signature is normally identified as similar.
  • the parameters of the sample surface are classified based on the comparison results. According to the invention, it is concluded that the sample surface has properties similar to the identified reference sample and is to be classified in the same class as this.
  • FIG. 5 shows the use of the method according to the invention for product detection by means of a flow chart.
  • the process steps are divided into process sections preliminary run 300 and production process section 400.
  • the process section preliminary run 300 contains the process step provision of reference signatures and describes them in substeps.
  • advance 300 (teaching in the system), a sufficiently large number of the structures to be examined (different product types in different manufacturing stages and / or with different production errors) are measured. Measurement of the location and / or intensity distribution of diffraction patterns on qualitatively specified production prototypes, 301 such a number of reference signatures 303.
  • a neural network can now be trained 305 and in the future perform product recognition itself. This provides reference signatures for finely structured surfaces for the production process section 400.
  • At least one signature of a sample surface to be checked is first measured in 401 by the measurement of Diffraction and / or scattering of electromagnetic radiation on the finely structured surfaces.
  • the measured signature is then compared with the reference signatures in 402.
  • the similarity of the signature to reference signatures is evaluated and at least one reference signature is normally identified as similar.
  • the parameters of the sample surface are then classified in 403 on the basis of the comparison results. According to the invention, it is concluded that the sample surface has properties similar to the identified reference sample and that the sample is identified as the same product as this reference sample. In this context, different stages of manufacture during the manufacture of a product type are understood as different products. If no reference signature is identified as similar, it is concluded according to the invention that the sample is faulty.
  • a precise fault analysis can be carried out 404 using absolute measuring devices in accordance with the prior art. This fault analysis can lead to a correction of the manufacturing process 405. With this method, product lots can be identified and faulty lines can be corrected. In addition, different stages of manufacture can be distinguished up to the completion of the semiconductor product.
  • Detector 52 directly reflected beam 54 secondary reflections 56, 58
  • Reference signatures 103 are used to examine the samples with a measuring device according to the prior art 102 which supplies absolute measured values 104 neural network is trained 105
  • a neural network can be trained 305

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Abstract

Procédé de contrôle de processus de fabrication de surfaces microstructurées dans la production de semi-conducteurs, qui consiste à disposer de signatures de référence (72) de surfaces microstructurées, à mesurer au moins une signature (74) de la surface d'échantillon à contrôler, à comparer (76) la signature mesurée aux signatures de référence, et à classifier (78) les paramètres de la surface d'échantillon à l'aide des résultats de la comparaison. Ledit procédé est caractérisé en ce que la mesure des signatures de référence est effectuée par mesure de la répartition spatiale et/ou d'intensité d'images de diffraction sur des prototypes de production qualitativement spécifiés. La classification (78) est effectuée de préférence avec un réseau neuronal adaptatif et/ou une logique floue. La présente invention concerne en outre un dispositif destiné à mettre en oeuvre ledit procédé. Les signatures sont produites par rotation des plans de polarisation du faisceau de lumière incidente sur l'échantillon.
EP99961050A 1998-12-04 1999-12-02 Dispositif et procede de controle optique de processus de fabrication de surfaces microstructurees dans la production de semi-conducteurs Withdrawn EP1145303A1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE19855983 1998-12-04
DE19855983 1998-12-04
DE19922614 1999-05-17
DE19922614A DE19922614A1 (de) 1998-12-04 1999-05-17 Verfahren und Vorrichtung zur optischen Kontrolle von Fertigungsprozessen feinstrukturierter Oberflächen in der Halbleiterfertigung
PCT/EP1999/009410 WO2000035002A1 (fr) 1998-12-04 1999-12-02 Dispositif et procede de controle optique de processus de fabrication de surfaces microstructurees dans la production de semi-conducteurs

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EP1145303A1 true EP1145303A1 (fr) 2001-10-17

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US (1) US7003149B2 (fr)
EP (1) EP1145303A1 (fr)
JP (1) JP3654630B2 (fr)
IL (1) IL143478A (fr)
WO (1) WO2000035002A1 (fr)

Families Citing this family (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6483580B1 (en) * 1998-03-06 2002-11-19 Kla-Tencor Technologies Corporation Spectroscopic scatterometer system
DE10014816B4 (de) 2000-03-27 2012-12-06 Nawotec Gmbh Verfahren zur Brechzahlbestimmung
US7115858B1 (en) 2000-09-25 2006-10-03 Nanometrics Incorporated Apparatus and method for the measurement of diffracting structures
IL139368A (en) 2000-10-30 2006-12-10 Nova Measuring Instr Ltd Process control for microlithography
US7225107B2 (en) * 2001-05-24 2007-05-29 Test Advantage, Inc. Methods and apparatus for data analysis
US6898537B1 (en) 2001-04-27 2005-05-24 Nanometrics Incorporated Measurement of diffracting structures using one-half of the non-zero diffracted orders
US6713753B1 (en) 2001-07-03 2004-03-30 Nanometrics Incorporated Combination of normal and oblique incidence polarimetry for the characterization of gratings
US7061615B1 (en) 2001-09-20 2006-06-13 Nanometrics Incorporated Spectroscopically measured overlay target
DE10146944A1 (de) * 2001-09-24 2003-04-10 Zeiss Carl Jena Gmbh Meßanordnung
DE10146945A1 (de) * 2001-09-24 2003-04-10 Zeiss Carl Jena Gmbh Meßanordnung und Meßverfahren
JP2005505929A (ja) * 2001-10-10 2005-02-24 アクセント オプティカル テクノロジーズ，インク． 断面解析による焦点中心の決定
US6560751B1 (en) * 2001-11-06 2003-05-06 Sony Corporation Total overlay feed forward method for determination of specification satisfaction
US7280230B2 (en) 2001-12-19 2007-10-09 Kla-Tencor Technologies Corporation Parametric profiling using optical spectroscopic systems
JP3578144B2 (ja) * 2002-01-16 2004-10-20 住友電気工業株式会社 回折型光学部品の光学特性測定装置及び測定方法
US6562635B1 (en) * 2002-02-26 2003-05-13 Advanced Micro Devices, Inc. Method of controlling metal etch processes, and system for accomplishing same
US6982793B1 (en) 2002-04-04 2006-01-03 Nanometrics Incorporated Method and apparatus for using an alignment target with designed in offset
US6949462B1 (en) 2002-04-04 2005-09-27 Nanometrics Incorporated Measuring an alignment target with multiple polarization states
EP1527320A1 (fr) * 2002-07-12 2005-05-04 Luka Optoscope ApS Procede et dispositif de mesure optique de la topographie de structures periodiques approximativement planes
US6992764B1 (en) 2002-09-30 2006-01-31 Nanometrics Incorporated Measuring an alignment target with a single polarization state
WO2004046655A2 (fr) * 2002-11-20 2004-06-03 Mehrdad Nikoohahad Systeme et procede pour caracterisation de structures tridimensionnelles
WO2004057317A1 (fr) * 2002-12-19 2004-07-08 Aminova Vision Technology Aps Procede pour classifier la qualite d'une surface
DE10302868B4 (de) * 2003-01-25 2008-07-03 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Verfahren zur Bestimmung von Strukturparametern einer Oberfläche mit einem lernfähigen System
US7265364B2 (en) * 2004-06-10 2007-09-04 Asml Netherlands B.V. Level sensor for lithographic apparatus
US7310155B1 (en) * 2004-10-04 2007-12-18 Advanced Micro Devices, Inc. Extraction of tool independent line-edge-roughness (LER) measurements using in-line programmed LER and reliability structures
US20070091325A1 (en) * 2005-01-07 2007-04-26 Mehrdad Nikoonahad Multi-channel optical metrology
US11024527B2 (en) 2005-06-18 2021-06-01 Frederick A. Flitsch Methods and apparatus for novel fabricators with Cleanspace
EP2050075A4 (fr) * 2006-07-18 2011-07-20 Univ Pennsylvania Procédé de séparation et d'accroissement de contrastes de composants d'ombre projetée se chevauchant et procédé de détection de cibles se trouvant dans l'ombre faisant intervenir la polarisation
US8699027B2 (en) * 2007-07-27 2014-04-15 Rudolph Technologies, Inc. Multiple measurement techniques including focused beam scatterometry for characterization of samples
TWI462048B (zh) * 2011-08-24 2014-11-21 Inotera Memories Inc 建立蝕刻側寫資料庫的方法
US20140011323A1 (en) * 2012-07-06 2014-01-09 Frederick Flitsch Processes relating to cleanspace fabricators
DE102012022966A1 (de) * 2012-11-21 2014-05-22 Friedrich-Schiller-Universität Jena Verfahren zur Auswertung von durch schmalbandige, kurzwellige, kohärente Laserstrahlung erzeugten Streubildern von Objektiven, insbesondere zur Verwendung in der XUV-Mikroskopie
CN105513985B (zh) * 2014-09-26 2018-08-10 中芯国际集成电路制造(上海)有限公司 光学量测方法
US10067072B2 (en) * 2015-07-10 2018-09-04 Kla-Tencor Corporation Methods and apparatus for speckle suppression in laser dark-field systems
EP3208657A1 (fr) * 2016-02-22 2017-08-23 Paul Scherrer Institut Procédé et système d'inspection de défaut à haut rendement utilisant le contraste dans le domaine de fréquence spatiale réduite
US11867891B2 (en) * 2016-12-22 2024-01-09 Advanced Optical Technologies, Inc. Polarimeter with multiple independent tunable channels and method for material orientation imaging
TWI768092B (zh) * 2017-08-07 2022-06-21 美商克萊譚克公司 用於臨界尺寸量測之檢測導引臨界位點選擇
CN107797391B (zh) * 2017-11-03 2020-04-24 上海集成电路研发中心有限公司 光学邻近校正方法
US11327012B2 (en) * 2018-05-07 2022-05-10 Unm Rainforest Innovations Method and system for in-line optical scatterometry
KR102589004B1 (ko) * 2018-06-18 2023-10-16 삼성전자주식회사 반도체 불량 분석 장치 및 그것의 불량 분석 방법
GB201816526D0 (en) * 2018-10-10 2018-11-28 Univ Nottingham Surface topography sensing

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60224041A (ja) 1984-04-23 1985-11-08 Toray Ind Inc 生理活性物質の検出方法
JPS61169750A (ja) 1985-01-23 1986-07-31 Hitachi Ltd ウエハパターン欠陥検査装置
JPH0610656B2 (ja) 1986-02-27 1994-02-09 株式会社神戸製鋼所 表面欠陥検出装置
US4964726A (en) * 1988-09-27 1990-10-23 General Electric Company Apparatus and method for optical dimension measurement using interference of scattered electromagnetic energy
IL99823A0 (en) * 1990-11-16 1992-08-18 Orbot Instr Ltd Optical inspection method and apparatus
US5830611A (en) 1992-03-05 1998-11-03 Bishop; Kenneth P. Use of diffracted light from latent images in photoresist for optimizing image contrast
US5703692A (en) 1995-08-03 1997-12-30 Bio-Rad Laboratories, Inc. Lens scatterometer system employing source light beam scanning means
DE19600423C2 (de) 1996-01-08 2001-07-05 Siemens Ag Elektrisch programmierbare Speicherzellenanordnung und Verfahren zu deren Herstellung
JPH09191032A (ja) 1996-01-11 1997-07-22 Hitachi Ltd プロセス異常監視方法および装置
JP3586970B2 (ja) 1996-05-27 2004-11-10 ソニー株式会社 微細パターンの検査方法および検査装置
US5768192A (en) 1996-07-23 1998-06-16 Saifun Semiconductors, Ltd. Non-volatile semiconductor memory cell utilizing asymmetrical charge trapping
US6366861B1 (en) * 1997-04-25 2002-04-02 Applied Materials, Inc. Method of determining a wafer characteristic using a film thickness monitor
DE19824624A1 (de) 1997-07-23 1999-02-25 Univ Ilmenau Tech Meßanordnung zur optischen Diffraktionsanalyse periodischer Submikrometerstrukturen
US6768165B1 (en) 1997-08-01 2004-07-27 Saifun Semiconductors Ltd. Two bit non-volatile electrically erasable and programmable semiconductor memory cell utilizing asymmetrical charge trapping
US6137570A (en) * 1998-06-30 2000-10-24 Kla-Tencor Corporation System and method for analyzing topological features on a surface

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0035002A1 *

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IL143478A0 (en) 2002-04-21
US20020051564A1 (en) 2002-05-02
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US7003149B2 (en) 2006-02-21
WO2000035002A1 (fr) 2000-06-15
IL143478A (en) 2005-09-25

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