WO2021125944A1 - A method and system for performing characterization measurements on an elongated substrate - Google Patents

A method and system for performing characterization measurements on an elongated substrate Download PDF

Info

Publication number
WO2021125944A1
WO2021125944A1 PCT/NL2020/050787 NL2020050787W WO2021125944A1 WO 2021125944 A1 WO2021125944 A1 WO 2021125944A1 NL 2020050787 W NL2020050787 W NL 2020050787W WO 2021125944 A1 WO2021125944 A1 WO 2021125944A1
Authority
WO
WIPO (PCT)
Prior art keywords
substrate
cantilevers
locations
cantilever
guided
Prior art date
Application number
PCT/NL2020/050787
Other languages
English (en)
French (fr)
Inventor
Paul ZABBAL
Original Assignee
Nearfield Instruments B.V.
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
Application filed by Nearfield Instruments B.V. filed Critical Nearfield Instruments B.V.
Priority to EP20828160.0A priority Critical patent/EP4078191A1/en
Publication of WO2021125944A1 publication Critical patent/WO2021125944A1/en

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01QSCANNING-PROBE TECHNIQUES OR APPARATUS; APPLICATIONS OF SCANNING-PROBE TECHNIQUES, e.g. SCANNING PROBE MICROSCOPY [SPM]
    • G01Q60/00Particular types of SPM [Scanning Probe Microscopy] or microscopes; Essential components thereof
    • G01Q60/24AFM [Atomic Force Microscopy] or apparatus therefor, e.g. AFM probes
    • G01Q60/32AC mode
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04Analysing solids
    • G01N29/06Visualisation of the interior, e.g. acoustic microscopy
    • G01N29/0654Imaging
    • G01N29/0681Imaging by acoustic microscopy, e.g. scanning acoustic microscopy
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01QSCANNING-PROBE TECHNIQUES OR APPARATUS; APPLICATIONS OF SCANNING-PROBE TECHNIQUES, e.g. SCANNING PROBE MICROSCOPY [SPM]
    • G01Q70/00General aspects of SPM probes, their manufacture or their related instrumentation, insofar as they are not specially adapted to a single SPM technique covered by group G01Q60/00
    • G01Q70/06Probe tip arrays
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00Indexing codes associated with group G01N29/00
    • G01N2291/04Wave modes and trajectories
    • G01N2291/042Wave modes
    • G01N2291/0427Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever

Definitions

  • the invention relates to a method for performing characterization measurements on an elongated substrate using a scanning probe microscopy system.
  • the invention further relates to a scanning probe microscopy system for performing sub-surface measurements on a substrate. Further, the invention relates to a computer program product.
  • Scanning probe microscopy (SPM) devices such as atomic force microscopy (AFM) devices are for example applied in the semiconductor industry for scanning of semiconductor topologies on a surface, for characterization of the semiconductor.
  • AFM atomic force microscopy
  • Other uses of this technology are found in biomedical industry, nanotechnology, and scientific applications.
  • AFM may be used for critical dimension metrology (CD-metrology), particle scanning, stress- and roughness measurements.
  • CD-metrology critical dimension metrology
  • particle scanning stress- and roughness measurements.
  • AFM microscopy allows visualization of surfaces at very high accuracy, enabling visualization of surface elements at sub -nanometer resolution.
  • Other surface scanning measurement devices for example include optical near field scanning devices.
  • the probe in a SPM system comprises a cantilever and a probe tip. On one end of the cantilever, the probe is attached to a sensor head, for example (but not necessarily) through an actuator that allows to bring the probe in motion.
  • Probe tip is usually located on the other end of the cantilever.
  • the probe tip can be scanned over the surface of a substrate or substrate to measure the topography and mechanical properties thereof.
  • a sensor in many cases an optical sensor, monitors the position of the probe tip.
  • the sensor may monitor a reflected laser beam that is reflected by the cantilever or the back of the probe tip, and which changes angle when the probe tip moves up or down.
  • the signal-to-noise ratio may be low as the frequency used is often from GHz up to THz, which can make ultrasound imaging rather difficult.
  • the stack mechanical properties are usually unknown. As there could be an opaque layer, optical methods are often limited.
  • the sub- surface features may be buried deep in a structure, for example from a few hundreds of nanometers to micrometers deep. It is desired to accurately be able to extract relevant dimension, which can be used for defect inspection and/or process control.
  • the invention provides for a method for performing characterization measurements on an elongated substrate using a scanning probe microscopy system, the system comprising a plurality of cantilevers, each cantilever having a probe tip arranged thereon, the method comprising the steps of: moving the cantilevers towards a surface of the substrate for enabling contact between the probe tips of the plurality of cantilevers and the surface of the substrate; vibrating at least one first cantilever of the plurality of cantilevers for emitting ultrasonic waves in the substrate at one or more first locations on the surface of the substrate, wherein the ultrasonic waves are adapted so as to propagate one or more guided waves into the substrate; detecting the generated guided waves at a plurality of second locations on the surface of the substrate by means of at least one second cantilever of the plurality of cantilevers, the plurality of second locations being distanced from the one or more first locations; and performing substrate characterization based on the detected guided waves at the plurality of second locations.
  • the elongated substrate can be characterized with ultrasonic guided waves.
  • the method can be used for effective characterization of subsurface features and/or other properties of the substrate.
  • a quantitative ultrasound approach can be provided exploiting a multimode waveguide response of elongated substrates (e.g. semiconductor device) for assessing properties such as subsurface features, sublayer thickness, mechanical properties (e.g. stiffness), etc.
  • Guided waves are capable of propagating long distances, thus making them an ideal candidate to interrogate large plate and shell structures, such as the elongated substrate.
  • Guided waves which are propagated within the elongated substrate are dispersive and the relationship between the frequency and the wave number, which is specific to each guided mode, is determined by the geometric and elastic properties of the waveguide. For example, changes in a sublayer thickness or elastic properties (e.g. due to a presence of a subsurface feature) can change the propagation characteristics of the guided waves. Consequently, guided waves measurements on long/elongated substrates have the potential for yielding properties of the elongated substrate which can be used as markers for identifying subsurface characteristics of the elongated substrate or judge whether the elongated substrate has the desired or expected properties.
  • the method can be used for evaluating and/or quantifying the mechanical integrity of the elongated substrate and/or other small-scale structures.
  • the method can be used for detection of defects in adhesion and deviation interfacial stiffness.
  • the guided waves measurements are performed with the plurality of cantilevers.
  • wideband ultrasonic pulses at a central frequency are transmitted, and the received signals are recorded.
  • the experimental dispersion curves which represent the frequency-dependent wave numbers, i.e. k(f), of guided modes propagating in the waveguide, can be determined in various ways.
  • the detected generated guided waves are used in dispersion imaging in which dispersion curves are identified, wherein mechanical properties of the substrate are determined based on the identified dispersion curves.
  • the elongated substrate can be described by distributed mass and stiffness.
  • a finite number of modes can be analyzed using modal decomposition.
  • the elongated substrate can be represented as guided waves, since the substrate is relatively thin in one direction.
  • the substrate can have higher dimensions in the other two directions.
  • the waves can travel long distances within the substrate before they decay.
  • the wave modes can be represented through dispersion curves, which provide a relationship between the wave number and the frequency. The dispersion curves can be seen as separate lines that each represent an individual mode.
  • Dispersion curves can effectively explain the dynamics of the elongated substrate (which can be seen as a coupled system). Dispersion curves also provide insight into what happens inside the system at different frequencies.
  • the elongated substrate is modelled, guided waves propagating along it are computed, and such waves are represented by means of dispersion curves.
  • the substrate characterization is performed based on one or more guided wave variations, wherein the detected generated guided waves at the plurality of second locations are used for determining the one or more guided wave variations.
  • Lamb waves can be dispersive and change shape as they propagate, meaning that the higher harmonics may travel at different group velocities than the fundamental portion. Lamb waves are multimode by nature, which can make it potentially difficult to separate the individual mode contributions from a complicated time-domain wave form.
  • the characteristics of the inspection waves after interacting with subsurface features can be determined.
  • One or more of the plurality of cantilevers can generate ultrasonic-guided waves which propagate into the structure of the elongated substrate, interacting with subsurface features, and carrying the subsurface information with them. These ultrasonic-guided waves having interacted with the internal structure of the elongated substrate can then be picked up again by cantilevers, e.g.
  • the subsurface features within the elongated substrate can be considered as a new wave source at a location of the subsurface feature.
  • the method can also be employed for determining thickness variations (e.g. of a sublayer of the elongated substrate).
  • An accurate and reliable procedure can be provided for measuring an harmonic of a guided wave (e.g. lamb wave) propagating in the elongated plate.
  • the elongated plate can be sufficiently long in order to ensure that the received signals are not influenced by boundary reflections.
  • the plurality of cantilevers are arranged in a cantilever array, the array including a first subset and a second subset, the first subset including the at least one first cantilever, and the second subset including the at least one second cantilever, wherein the second subset includes multiple cantilevers regularly spaced with respect to each other enabling detection of the generated guided waves at the plurality of second locations on the surface of the substrate.
  • the guided waves measurements can be performed with a plurality of cantilevers arranged in one or more arrays.
  • the one or more arrays each having multiple cantilevers can be brought in contact with the substrate for performing measurements.
  • the first subset includes multiple cantilevers arranged for successively emitting ultrasonic waves in the substrate so as to generate successive guided waves propagating into the substrate, and wherein the cantilevers of the second subset are used for retrieving each successively generated guided wave in response to the emitted ultrasonic waves.
  • the probe tips of the array of cantilevers can touch the sample surface and one or more of the probe tips of the first subset can coordinately emit a guided wave within the sample.
  • the return signal can then be measured by the probe tips.
  • the cantilevers of the array can both act as an emitter and receiver. In an example, one cantilever emits a wave in the sample, and then all the cantilevers are used for measuring the return signal.
  • the array and the substrate are movable with respect to each other, wherein the array is scanned over an area of the surface of the substrate for performing multiple measurements.
  • two or more cantilevers of the first subset are used for concurrently emitting ultrasonic waves in the substrate, wherein the concurrently emitted ultrasonic waves are coordinated in order to select a guided mode.
  • a guided mode selection can be performed based on the AFM/SPM emission reception.
  • the mode can be selected using the cantilevers (e.g. multilayer case).
  • the right mode that is sensitive to a layer for example for thickness extraction, or sensitive to a subsurface feature can be selected.
  • a line of cantilevers with an arbitrary waveform generator can be employed, for performing a guided mode selection in order to excite the specific desired mode.
  • the selected guided mode has a higher sensitivity to at least one of: a subsurface feature of the substrate, or one layer of the substrate having multiple layers. For example, if a specific mode is found sensitive to a layer that causes issue in the semiconductor device, this technique can be used.
  • the guided wave selection can be done using the cantilevers as emitters. For each selected mode, different signals can be emitted.
  • a plurality of guided modes are selected, wherein substrate characterization is performed by emitting the plurality of selected guided modes into the substrate.
  • the at least one second cantilever is scanned over the surface of the substrate for detecting at the plurality of locations the emitted guided waves.
  • a multi-layer substrate preferably a multi-layer semiconductor substrate, is characterized.
  • the substrate characterization includes at least one of: characterization of subsurface features in the substrate, characterization mechanical properties of the substrate, characterization of one or more layers or thickness variations of a multi-layer substrate, characterization of heterogeneities or voids in the substrate, or non-destructive testing of the substrate.
  • more than three cantilevers are provided, more preferably more than five cantilevers, even more preferably more than ten cantilevers.
  • an inverse method using an elongated plate model is applied for retrieving properties (e.g. thickness, stiffness) of the elongated plate from experimental data obtained by means of the cantilevers.
  • a singular value decomposition is applied to a response matrix at each frequency.
  • Signal-to-noise ratio (SNR) enhancement can be achieved by removing the singular vectors corresponding to the lowest singular values.
  • Different dispersion curves imaging techniques can be used for the detection of subsurface features in a semiconductor device.
  • the system can be operated in different modes in order to obtain high quality imaging.
  • a single emitter e.g. 2D-FT, Linear Radon Transform etc.
  • more advanced techniques can be used, such as for instance SVD- based method.
  • Dispersion curves are highly sensitive to the mechanical properties of the sample and therefore can be used for acoustic inspection: detection of subsurface features but also the determination of thickness variation in a multilayer, or even for non-destructive testing with the possibility to detect heterogeneities or voids.
  • the mechanical properties of a device can be determined based on dispersion curves. If the mechanical properties are determined, it is possible to accurately characterize the subsurface feature.
  • a subsurface feature in the elongated substrate can act as a new wave source (cf. transmission + mode conversion and reflection + mode conversion).
  • the system can be configured to launch a lamb mode into the substrate.
  • a lamb wave propagating into the elongated substrate can then be measured.
  • the generated lamb wave(s) can be detected by one or more cantilevers of the array, which can effectively measure the out-of-plane displacement and/or velocity of a point location on the surface of the substrate. By means of the array, the measurements can be performed over a range of propagation distances.
  • the elongated substrate can be a plate-like sample.
  • the substrate can be sufficiently long in order to ensure that the received signals are not influenced by boundary reflections.
  • the wave propagating into the elongated substrate can interact with one or more subsurface features. After the interaction with the subsurface substrate feature(s), information can be carried with them (subsurface feature can act as a new wave source), and this additional information, relating to the subsurface feature(s) can be picked up by one or more cantilevers of the array (cf. different from the emitter cantilever(s)).
  • the invention provides for a computer program product downloadable from a communication network and/or stored on a computer- readable and/or microprocessor-executable medium, comprising program code instructions that, when executed by a scanning probe microscopy system including a processor, causes the system to perform a method according to the invention.
  • Fig. 1 shows a schematic diagram of an embodiment of a system
  • Fig. 2 shows a schematic diagram of an embodiment of a system
  • Fig. 3 shows a schematic diagram of an embodiment of a system
  • Fig. 4 shows a schematic diagram of dispersion curves
  • Fig. 5 shows a schematic diagram of dispersion curves
  • Fig. 6 shows a schematic diagram of plots
  • Fig. 7 shows a schematic diagram of a system
  • Fig. 8 shows a schematic diagram of a method.
  • Fig. 1 shows a schematic diagram of an embodiment of a system 1.
  • the system 1 is a scanning probe microscopy system for performing sub -surface measurements on an elongated substrate 3.
  • the system 1 includes a sensor head 5 including a plurality of cantilevers 9, each cantilever 9 having a probe tip 11 arranged thereon.
  • the system 1 further comprises a processor configured to perform the steps of: moving the cantilevers 9 towards a surface 3a of the substrate 3 for enabling contact between the probe tips 11 of the plurality of cantilevers 9 and the surface 3a of the substrate 3; vibrating at least one first cantilever of the plurality of cantilevers 9 for emitting ultrasonic waves in the substrate at one or more first locations on the surface 3a of the substrate 3, wherein the ultrasonic waves are adapted so as to propagate one or more guided waves into the substrate 3; detecting the generated guided waves at a plurality of second locations on the surface of the substrate by means of at least one second cantilever of the plurality of cantilevers 9, the plurality of second locations being distanced from the one or more first locations; and performing substrate characterization based on the detected guided waves at the plurality of second locations.
  • the sample is a multi-layer sample including a first layer 17a and a second layer 17b. It will be appreciated that also a single layer sample 3 can be used. It is also possible to use a sample 3 with a larger number of layers.
  • the sensor head 5 and the sample 3 can be moveable with respect to each other as indicated by arrows 19.
  • the array of probes 7 may be moveable with respect to the sample along a surface 3a therefor for performing multiple measurements at different locations on said surface 3a. It will be appreciated that other relative moving directions are also possible.
  • a set of cantilevers 9 can be placed in a line regularly spaced and separated by a pitch.
  • the cantilevers or probes can be arranged in a matrix arrangement (e.g. multi-array).
  • the arbitrary waveform is generated with as many channels as the number of cantilevers in the array of probes.
  • an ultrasound piezo/PZT phased arrays may have between 32 up to 256 transducers or probes. However other numbers are also possible, for instance up to thousands of probes (e.g. piezo/PZT transducers).
  • Different excitation mechanisms can be employed for the cantilevers, such as at least one of piezo, photo-thermal, etc.
  • reception systems for the cantilevers can be employed. Examples are piezo-electric (PZT), optical beam deflection (OBD), etc.
  • a plurality of cantilevers are employed for generating guided waves and determining dispersion curves, wherein imaging of the sample is performed based on the dispersion curves.
  • An ultrasound wave can be emitted in a substrate by means a first cantilever, the substrate can be scanned by a second cantilever for detecting one or more guided waves variations, and a subsurface location can be determined based on the detected one or more guided waves variation.
  • Different types of dispersion imaging methods can be employed, such as for example 2D Fourier transfer, linear radon transform, etc.
  • multiple cantilevers are arranged in an array and brought in contact with a surface of the elongated substrate, providing different contact points.
  • the array of cantilevers may have a subset of emitters (e.g. one or more cantilevers) and a subset of receivers (e.g. one or more cantilevers) in the array. Different configurations are possible, for example 5 emitters, 20 receivers; 1 emitter, 100 receivers; etc.
  • the subset of receivers includes multiple cantilevers, providing a plurality of measuring locations on the surface of the substrate by the cantilevers being regularly spaced from each other.
  • An emitter cantilever can send one or more pulses at a frequency in GHz.
  • Fig. 2 shows a schematic diagram of an embodiment of a system 1.
  • the system includes an array of probes 7 for performing (subsurface) characterization of the substrate 3.
  • the array of probes 7 is brought in contact to the surface 3a of the substrate 3.
  • the substrate is a semiconductor device includes a subsurface feature 15 (Si02) and two layers (a Si bottom layer attached to an upper layer).
  • the upper layer may for instance have a thickness around 200 nm
  • the lower layer may for instance have a thickness around 150 nm.
  • the subsurface feature may for instance have a thickness of 100 nm.
  • At least one first cantilever of the plurality of cantilevers can be vibrated for emitting ultrasonic waves in the substrate at one or more first locations on the surface of the substrate. These ultrasonic waves are adapted so as to propagate one or more guided waves into the substrate. An exemplary excitation signal in time domain and frequency domain is shown. Subsequently, the generated guided waves at a plurality of second locations on the surface of the substrate can be detected by means of at least one second cantilever of the plurality of cantilevers, the plurality of second locations being distanced from the one or more first locations. This process may be optionally repeated a coupled of times.
  • the substrate characterization can be carried out based on the detected guided waves at the plurality of second locations.
  • Fig. 3 shows a schematic diagram of an embodiment of a system 1 with a plurality of probes arranged in an array of probes 7.
  • the probes 7i are schematically represented as boxes next to each other. This figure illustrates a measurement technique employed using the array of probes 7, namely different successive steps (a)-(i) are illustrated.
  • a first probe 7-1 is actuated.
  • the cantilever of the first probe 7-1 is vibrated in order to emit an ultrasonic wave in the sample. This emitting cantilever is also indicated by “E”.
  • the ultrasonic wave is adapted so as to propagate one or more guided waves into the substrate.
  • a generated guided wave is determined by each of the cantilevers 7-R (also indicated with letter “R”.
  • a second probe 7-2 is vibrated in order to emit an ultrasonic wave in the sample.
  • the induced guided wave is again determined by each of the cantilevers 7-R of the receiving subset of cantilever.
  • a next probe, third probe 7-3 is vibrated in order to emit an ultrasonic wave in the sample, again propagating one or more guided waves in the elongated substrate.
  • a subsequent sixth step (f) the generated guided wave(s) is again retrieved by each of the cantilevers 7-R.
  • This process can be repeated until all probes 7-E of a first subset of emitting probes have been actuated individually, and a resulting return signal is measured by all the probes of a receiving subset 7-R of probes.
  • a single probe is vibrated at a time during actuation, it is also possible that successive measurements are performed wherein consecutively a subset of cantilevers are concurrently vibrated in order to emit an acoustic wave in the sample.
  • a return signal can be retrieved by each of the cantilevers of the second subset of probes 7-R.
  • the array of probes 7 includes a total number of twenty probes 7-1 to 7-20 arranged next to each other.
  • a different number of probes may also be arranged in accordance with the invention.
  • Fig. 4 shows a schematic diagram of dispersion curves 20.
  • Dispersion curves are a representation in frequency and wavenumber, or frequency and phase velocity of the guided waves in a structure and are depending on the parameters of the structure (cf. elastic Modulus, thickness, density, Poisson’s ratio). Lamb modes can be subdivided in 2 categories, namely a symmetric and an asymmetric mode.
  • the cantilevers can be used for guided waves dispersion curves imaging and for selection of a guide mode.
  • the elongated substrate may for instance be a semiconductor device.
  • At least one cantilever can emit an ultrasound wave (preferably large band in order to obtain the higher number of modes) in a semiconductor device.
  • At least one second cantilever can detects the guided waves variation to determine the subsurface feature location for example.
  • Example of possible dispersion curves imaging method based on this configuration are 2D- Fourier Transform or Linear Radon Transform.
  • the plurality of probes can be used as multiple emitters.
  • One cantilever can be used at different locations, increasing the number of sources, or multiple cantilevers are used in a configuration as presented here. Increasing the number of sources can be useful and permit the use of better imaging methods such as: SVD- based methods, or Multichannel-MUSIC.
  • a scan of the surface under the multicantilever element can be scanned.
  • Dispersion curves can be used for detecting subsurface features.
  • the mechanical properties of the sample can be measured based on dispersion curves measurements. Therefore, possible material properties variations (thickness, Young’s modulus etc.), subsurface features, and also possible defects such as voids in the elongated substrate can be detected.
  • dispersion curves are depicted for a two cases.
  • a first case ON’ the elongated substrate has a subsurface feature
  • the second case OFF’ the elongated substrate is free of the subsurface feature.
  • FEM finite element method
  • the results are obtained with one cantilever acting as an emitter, and the other cantilevers in the array acting as receivers.
  • one cantilever was used as emitter, and 100 other cantilevers in the array were used as receivers. It is also possible to use a different number of cantilevers.
  • a specific lamb mode can be launched into the elongated plate, and the generated lamb waves can be detected with contact SPM probes/cantilevers of the array. In this way, the out-of-plane particle velocity of a point on the surface of the substrate can for instance be measured.
  • the measurements can be performed over a range of propagation distances by means of the multiple arrays of the array of probes.
  • Fig. 5 shows a schematic diagram of dispersion curves for the ON’ case (subsurface feature present) and the OFF’ case (subsurface feature not present).
  • the elongated substrate has a plurality of sublayers (multilayer substrate)
  • a guided mode selection can be achieved by using the plurality of arrays in order to excite the specific desired node.
  • the array may for instance have one or more lines of cantilevers providing an arbitrary waveform generator.
  • the guided mode selection can be based on AFM emission/reception. If a specific mode is found sensitive to a layer that causes issues (e.g. to be detected), this technique can be employed for obtaining improved results.
  • Fig. 6 shows a schematic diagram of plots relating to performing a mode selection.
  • a signal e.g. Gaussian signal
  • the response can then be measured in order to obtain the measured response.
  • This measured response can be fitted to a simulated response (e.g. least squares algorithm).
  • One or more relevant modes can be identified.
  • Plots (a), (b) and (c) relate to selecting mode in an OFF’ case (subsurface feature(s) not present).
  • Plots (d), (e) and (f) relate to selecting mode in an ON’ case (subsurface feature(s) present).
  • a fourth mode is select and excited.
  • a gain of almost 15dB is obtained after the mode selection in comparison to the other modes.
  • the plurality of cantilevers can be concurrently employed for shaping a wavefront, by applying different signals to different cantilevers. The wavefront can be shaped based on the selected mode.
  • Fig. 7 shows a schematic diagram of a system 1.
  • the system 1 includes a probe head 5 with an array 7 of probes. Each probe has a cantilever 9 with a probe tip 11.
  • two or more cantilevers of the first subset are used for concurrently emitting ultrasonic waves in the substrate, wherein the concurrently emitted ultrasonic waves are coordinated in order to select a guided mode.
  • the selected guided mode can have a higher sensitivity to at least one of: a subsurface feature of the substrate, or one layer of the substrate having multiple layers. For each selected mode, different signals can be emitted.
  • the signal to emit by the cantilevers can be determined by the following equation: in which s n (t) corresponds to a signal to emit by the cantilever n, G n (t) corresponds to a signal corresponding to the n th cantilever, / corresponds to the frequency, V ⁇ (f) corresponds to a phase velocity of selected mode, d n corresponds to a distance of n th cantilever from the first one, and FT corresponds to a Fourier Transform.
  • Fig. 8 shows a schematic diagram of a method 100 for performing characterization measurements on an elongated substrate using a scanning probe microscopy system, the system comprising a plurality of cantilevers, each cantilever having a probe tip arranged thereon.
  • the cantilevers are moved towards a surface of the substrate for enabling contact between the probe tips of the plurality of cantilevers and the surface of the substrate.
  • at least one first cantilever of the plurality of cantilevers are vibrated for emitting ultrasonic waves in the substrate at one or more first locations on the surface of the substrate, wherein the ultrasonic waves are adapted so as to propagate one or more guided waves into the substrate.
  • a third step 103 the generated guided waves are detected at a plurality of second locations on the surface of the substrate by means of at least one second cantilever of the plurality of cantilevers, the plurality of second locations being distanced from the one or more first locations.
  • substrate characterization is performed based on the detected guided waves at the plurality of second locations.
  • the method may include computer implemented steps. All above mentioned steps can be computer implemented steps.
  • Embodiments may comprise computer apparatus, wherein processes performed in computer apparatus.
  • the invention also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice.
  • the program may be in the form of source or object code or in any other form suitable for use in the implementation of the processes according to the invention.
  • the carrier may be any entity or device capable of carrying the program.
  • the carrier may comprise a storage medium, such as a ROM, for example a semiconductor ROM or hard disk.
  • the carrier may be a transmissible carrier such as an electrical or optical signal which may be conveyed via electrical or optical cable or by radio or other means, e.g. via the internet or cloud.
  • Some embodiments may be implemented, for example, using a machine or tangible computer-readable medium or article which may store an instruction or a set of instructions that, if executed by a machine, may cause the machine to perform a method and/or operations in accordance with the embodiments.
  • Various embodiments may be implemented using hardware elements, software elements, or a combination of both.
  • hardware elements may include processors, microprocessors, circuits, application specific integrated circuits (ASIC), programmable logic devices (PLD), digital signal processors (DSP), field programmable gate array (FPGA), logic gates, registers, semiconductor device, microchips, chip sets, et cetera.
  • software may include software components, programs, applications, computer programs, application programs, system programs, machine programs, operating system software, mobile apps, middleware, firmware, software modules, routines, subroutines, functions, computer implemented methods, procedures, software interfaces, application program interfaces (API), methods, instruction sets, computing code, computer code, et cetera.
  • API application program interfaces
  • any reference signs placed between parentheses shall not be construed as limiting the claim.
  • the word ‘comprising’ does not exclude the presence of other features or steps than those listed in a claim.
  • the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality.
  • the mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to an advantage.

Landscapes

  • Physics & Mathematics (AREA)
  • General Health & Medical Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Radiology & Medical Imaging (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Chemical & Material Sciences (AREA)
  • Biochemistry (AREA)
  • Analytical Chemistry (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Acoustics & Sound (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
PCT/NL2020/050787 2019-12-16 2020-12-15 A method and system for performing characterization measurements on an elongated substrate WO2021125944A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP20828160.0A EP4078191A1 (en) 2019-12-16 2020-12-15 A method and system for performing characterization measurements on an elongated substrate

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL2024470A NL2024470B1 (en) 2019-12-16 2019-12-16 A method and system for performing characterization measurements on an elongated substrate
NL2024470 2019-12-16

Publications (1)

Publication Number Publication Date
WO2021125944A1 true WO2021125944A1 (en) 2021-06-24

Family

ID=70295977

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL2020/050787 WO2021125944A1 (en) 2019-12-16 2020-12-15 A method and system for performing characterization measurements on an elongated substrate

Country Status (3)

Country Link
EP (1) EP4078191A1 (nl)
NL (1) NL2024470B1 (nl)
WO (1) WO2021125944A1 (nl)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19729280C1 (de) * 1997-07-09 1998-11-05 Fraunhofer Ges Forschung Ultraschallmikroskop
JP2012083130A (ja) * 2010-10-07 2012-04-26 Fujitsu Ltd 超音波検査方法及び超音波検査装置
EP3232192A1 (en) * 2016-04-14 2017-10-18 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Heterodyne scanning probe microscopy method, scanning probe microscopy system and probe therefore
CN104965105B (zh) * 2015-07-06 2018-03-23 中国科学院半导体研究所 集成超声换能器的afm探针阵列
EP3396390A1 (en) * 2017-04-24 2018-10-31 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Subsurface atomic force microscopy with guided ultrasound waves

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19729280C1 (de) * 1997-07-09 1998-11-05 Fraunhofer Ges Forschung Ultraschallmikroskop
JP2012083130A (ja) * 2010-10-07 2012-04-26 Fujitsu Ltd 超音波検査方法及び超音波検査装置
CN104965105B (zh) * 2015-07-06 2018-03-23 中国科学院半导体研究所 集成超声换能器的afm探针阵列
EP3232192A1 (en) * 2016-04-14 2017-10-18 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Heterodyne scanning probe microscopy method, scanning probe microscopy system and probe therefore
EP3396390A1 (en) * 2017-04-24 2018-10-31 Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO Subsurface atomic force microscopy with guided ultrasound waves

Also Published As

Publication number Publication date
EP4078191A1 (en) 2022-10-26
NL2024470B1 (en) 2021-09-02

Similar Documents

Publication Publication Date Title
US10001457B2 (en) Performance curve generation for non-destructive testing sensors
JP6392331B2 (ja) 誘電性物質の厚さまたは深さの非破壊的絶対測定
TWI766932B (zh) 外差式原子力顯微術裝置、方法以及微影製程系統
Trushkevych et al. Characterisation of small defects using miniaturised EMAT system
WO2009104811A9 (ja) 超音波計測装置及び超音波計測方法
KR20090017769A (ko) 콘크리트 포장의 비파괴검사 방법
Kuts et al. Study of parametric transducer operation in pulsed eddy current non-destructive testing
CN105572229A (zh) 部件无损测试系统的校准的验证方法及组装件
Etxaniz et al. Ultrasound-based structural health monitoring methodology employing active and passive techniques
EP2984479B1 (en) Ultrasonic inspection using incidence angles
NL2024470B1 (en) A method and system for performing characterization measurements on an elongated substrate
CN117169231A (zh) 一种基于声光技术的复合材料无损检测系统
Aldrin et al. Scattering of obliquely incident shear waves from a cylindrical cavity
NL2024466B1 (en) A method and system for performing sub-surface measurements on a sample
US20230228717A1 (en) Method for non-destructively testing objects, in particular planar objects, made of a fibre-reinforced composite material
NL2024467B1 (en) A method and system for performing sub-surface measurements on a sample
NL2025275B1 (en) Method of determining dimensions of features of a subsurface topography, scanning probe microscopy system and computer program.
JP2012083130A (ja) 超音波検査方法及び超音波検査装置
JP5853445B2 (ja) 検査装置及び検査方法
US11327092B2 (en) Subsurface atomic force microscopy with guided ultrasound waves
KR102116051B1 (ko) 배열형 초음파 센서를 이용한 펄스 에코형 비선형 검사 장치
Chen et al. Thickness measurement optimisation for permanently installed inductively coupled ultrasonic transducer systems
Yassin et al. Surface defects mapping using microwaves and ultrasonic phased array imaging
CN110609083A (zh) 基于超声相控阵的薄板三维机织层合板复合材料试件内部缺陷检测方法
CN103837580A (zh) 一种基于超声和电磁超声相结合的双模无损检测方法及装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20828160

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2020828160

Country of ref document: EP

Effective date: 20220718