JP7346778B2 - An atomic microscope equipped with an optical measurement device and a method for obtaining information on the surface of a measurement target using the same - Google Patents

Description

The present invention relates to an atomic microscope equipped with an optical measurement device and a method using the same to obtain information on the surface of a measurement target, and more specifically, the present invention relates to an atomic microscope equipped with an optical measurement device and a method for obtaining information on the surface of a measurement target using the same. The present invention relates to an atomic microscope equipped with an optical measurement device that obtains shape information using an optical measurement device by referring to characteristic values, and a method of obtaining information about the surface of a measurement target using the same.

Optical measurement equipment constructs a simulation model of a repeated structure (lattice) on the surface of the object to be measured, and then uses light properties such as diffraction and polarization to fit the simulation model constructed from the measurement results. It refers to a measurement device implemented using scatterometry or OCD (Optical Critical Dimension) technology, which is based on fitting.

Recently, optical measurement devices have been used to measure not only repeated structures but also non-periodic structures using machine learning methodologies. Of course, the use of such machine learning methodologies has also been exploited with repeated structures (periodic structures).

Such optical measurement devices have the advantage of being able to perform high-speed measurements and have excellent reproducibility even after repeated measurements, but they require a long setup time before making measurements, making it difficult to As the number of parameters increases, the fitting calculation becomes complicated, which has the disadvantage that it is difficult to obtain an accurate shape.

To compensate for the shortcomings of such optical measuring devices, additional measuring devices such as CD-SEM can be utilized, but the accuracy of CD-SEM is not sufficient to compensate for the shortcomings of optical measuring devices. is the reality.

The present invention was devised to solve the above-mentioned problems, and the problem to be solved by the present invention is to refer to characteristic values extracted using shape information obtained by an atomic microscope. An object of the present invention is to provide an atomic microscope equipped with an optical measurement device, which obtains shape information using an optical measurement device, and a method for obtaining shape information of a surface of a measurement object using the same.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above problems, an atomic microscope equipped with an optical measuring device according to an embodiment of the present invention utilizes an XY scanner that supports the measurement object to scan the measurement object on the XY plane while scanning the measurement object with a probe. ) along the surface of the measurement object to obtain characteristics of the surface of the measurement object, an illumination unit that makes light incident on the surface of the measurement object, and detecting light reflected from the surface of the measurement object. an optical measurement device that obtains characteristics of the surface of the measurement target through scanning with the XY scanner; and a detection unit that controls the operation of the atomic microscope and the optical measurement device; and a control device for receiving the obtained data. The control device is controlled so that the position measured by the atomic microscope and the position measured by the optical measurement device can be matched with each other.

According to another feature of the invention, the illumination section is configured to make light incident near the probe.

According to still another feature of the present invention, the illumination section makes light obliquely incident on the surface of the measurement object so that the probe is located between the illumination section and the detection section.

According to yet another feature of the present invention, the illumination unit is configured to vertically enter light from above the probe.

According to still another feature of the present invention, by moving the probe relative to the surface of the object to be measured or moving the optical measuring device relative to the surface of the object to be measured, the atomic microscope measures The position is configured to match the position measured by the optical measuring device.

According to still another feature of the invention, the atomic microscope and the optical measuring device are arranged such that an offset occurs between a position measured by the atomic microscope and a position measured by the optical measuring device. is placed.

A method of obtaining surface information of a measurement target according to an embodiment of the present invention to solve the above problem is a method of obtaining shape information of a measurement target surface using an atomic microscope equipped with the above-mentioned optical measurement device. an atomic microscope measurement step of obtaining shape information of a specific point on the surface of the object to be measured using the atomic microscope; and a characteristic value for the shape through the shape information of the specific point obtained in the atomic microscope measurement step. and an optical measurement step of obtaining shape information of a region including the specific point on the surface of the object to be measured using the optical measurement device while referring to the characteristic value.

According to another feature of the present invention, the characteristic value is at least one of height, top width, bottom width, corner rounding radius, surface roughness, period, and sidewall angle (SWA).

A method of obtaining surface information of a measurement target according to another embodiment of the present invention to solve the above problems uses an atomic microscope equipped with the above-mentioned optical measurement device to obtain shape information of the measurement target surface. The method includes the steps of measuring a specific region with the optical measurement device, and measuring a partial region with the atomic microscope based on measurement data by the optical measurement device.

A method for obtaining shape information on the surface of a measurement target according to another embodiment of the present invention to solve the above problems uses an atomic microscope equipped with the above-mentioned optical measurement device to obtain information on the surface of the measurement target. The method includes the steps of: bringing a probe of the atomic microscope close to the surface of the object to be measured; and irradiating light between the probe and the surface of the object using an illumination section of the optical measurement device. generating localized surface plasmon resonance in the localized surface plasmon resonance; obtaining information about the measurement target from the probe that interacts with the electric field generated by the localized surface plasmon resonance; and obtaining at least amplified information from the detection section of the optical measurement device. obtaining a signal including a Raman spectral signal, the probe being coated with metal.

According to another feature of the invention, the proximate step is a step of approaching the probe in a non-contact mode.

According to yet another feature of the invention, the step of obtaining the signal further includes obtaining a signal related to an absorption spectrum.

According to the atomic microscope equipped with the optical measuring device of the present invention and the method of obtaining the shape information of the surface of the object to be measured using the same, the disadvantage of the atomic microscope is the long measurement time and the inaccuracy of the optical measuring device due to the complicated shape. By mutually complementing the shortcomings of the short fitting, more accurate profile shape data can be obtained in a short time. Furthermore, since the optical measurement device is integrally attached to the atomic microscope, it is easy to combine data obtained from the atomic microscope and data obtained from the optical measurement device. Furthermore, it is possible to improve the overall measurement speed by measuring only the necessary portions with an atomic microscope based on the measurement data of the optical measurement device. In addition, by integrating an optical measurement device and an atomic microscope, companies that manufacture components such as semiconductors and displays, which frequently use both measurement devices, can reduce investment costs, maintenance costs, labor costs, and other costs. You can save money.

FIG. 2 is a schematic perspective view of an atomic microscope in which an XY scanner and a Z scanner are separated. FIG. 2 is a conceptual diagram illustrating a method of measuring a measurement target using an optical system. 1 is a schematic front view of an atomic microscope including an optical measurement device according to an embodiment of the present invention; FIG. FIG. 2 is a schematic front view of an atomic microscope including an optical measurement device according to another embodiment of the present invention. 5 is a flowchart sequentially illustrating a method for obtaining shape information on a surface of a measurement target using an atomic microscope equipped with the optical measurement device of FIG. 3 or 4. FIG. FIG. 3 is a conceptual diagram showing an example of characteristic values. 2 is a graph of an image of a physical model generated using a CD-SEM and a spectrum measured using characteristic values from the physical model. 2 is a graph of an image of a physical model generated using an atomic microscope and a spectrum measured using characteristic values from the physical model. 6 is a flowchart sequentially illustrating a method for obtaining shape information on the surface of a measurement target, which is different from the method shown in FIG. 5. FIG. FIG. 4 is a schematic front view of an atomic microscope including the optical measurement device of FIG. 3, which is operated to measure physical property values by localized surface plasmon resonance. 11 is a flowchart of a method of obtaining information on the surface of a measurement target using the apparatus of FIG. 10.

The advantages and features of the invention, as well as the manner in which they are achieved, will become clearer with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various forms different from each other, and these embodiments are merely intended to complete the disclosure of the present invention, and are not limited to the embodiments disclosed herein. It is provided to fully convey the scope of the invention to those of ordinary skill in the art, and the invention is defined only by the scope of the claims that follow.

Although the terms first, second, etc. are used to describe various components, it should be understood that these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may also be the second component within the technical spirit of the present invention. Furthermore, it goes without saying that the description that the second coating is performed after the first coating is also included within the technical idea of the present invention, as well as the description that the second coating is performed after the first coating.

When using drawing numbers in this specification, even if the drawings are different, if the same configuration is illustrated, the same drawing numbers are used as much as possible.

The size and thickness of each structure shown in the drawings are illustrated for convenience of explanation, and the present invention is not necessarily limited to the size and thickness of the illustrated structure.

<Configuration of atomic microscope>
First, the configuration of an atomic microscope without an optical measurement device will be described.

FIG. 1 is a schematic perspective view of an atomic microscope in which an XY scanner and a Z scanner are separated, and FIG. 2 is a conceptual diagram illustrating a method of measuring an object using an optical system.

Referring to FIG. 1, the atomic microscope 100 includes a probe 110, an XY scanner 120, a head 130, a Z stage 140, a fixed frame 150, and a controller 160.

The probe 110 includes a tip and a cantilever, and is configured such that the tip follows the surface of the measurement object 1 in contact or in a non-contact state. The probe 110 can be freely selected from various forms used in an atomic microscope.

The XY scanner 120 is configured to move the measurement object 1 such that the tip moves relative to the surface of the measurement object 1 in at least a first direction. Specifically, the XY scanner 120 functions to scan the measurement object 1 in the X direction and the Y direction on the XY plane.

The head 130 is configured such that the probe 110 can be attached thereto, and includes an optical system capable of measuring vibration or deflection of the cantilever, and a distance between the tip and the surface to be measured based on the data obtained by the optical system. A Z-scanner 131 is configured to controllably move the probe 110 in at least the second direction and the opposite direction. The optical system will be described below with reference to FIG. Here, the Z scanner 131 moves the probe 110 with a relatively small displacement.

Z stage 140 moves probe 110 and head 130 in the Z direction with a relatively large displacement.

Fixed frame 150 fixes XY scanner 120 and Z stage 140.

Controller 160 is configured to control at least XY scanner 120, head 130, and Z stage 140. The controller 160 may be a control device itself, which will be described later, or may be included in a separate control device.

Meanwhile, the atomic microscope 110 may further include an XY stage (not shown) configured to move the XY scanner 120 on the XY plane with a large displacement. In this case, the XY stage is fixed to fixed frame 150.

The atomic microscope 100 scans the surface of the measurement object 1 with a probe 110 to obtain images such as topography. The relative movement between the surface of the measurement object 1 and the probe 110 can be performed by the XY scanner 120, and the movement of the probe 110 up and down along the surface of the measurement object 1 can be performed by the Z scanner 131. I can do it. Meanwhile, the probe 110 and the Z scanner 131 are connected by a probe arm (132).

Referring to FIG. 2, the XY scanner 120 supports the measurement object 1 and scans the measurement object 1 in the XY directions. The driving of the XY scanner 120 can be generated by, for example, a piezoelectric actuator, and if it is separated from the Z scanner 131 as in this embodiment, a stacked piezoelectric actuator is used. You can also do that. Regarding the XY scanner 120, Korean registered patent No. 10-0523031 (Title of invention: XY scanner in scanning probe microscope and its driving method) and No. 10-1468061 (Title of invention) of which the present applicant is the registration right holder. : Scanner control method and scanner device using the same).

The Z scanner 131 is connected to the probe 110 and can adjust the height of the probe 110. The Z scanner 131 can also be driven by a piezoelectric actuator like the XY scanner 120. Regarding the Z scanner 131, reference is made to Korean Patent No. 10-1476808 (title of invention: scanner device and atomic microscope including the same), of which the present applicant is the registered right holder. When the Z scanner 131 contracts, the probe 110 moves away from the surface of the measurement object 1, and when the Z scanner 131 expands, the probe 110 moves closer to the surface of the measurement object 1.

Since the XY scanner 120 and the Z scanner 131 are separated and exist as separate members as shown in FIGS. 1 and 2, the optical measuring device can perform measurements by scanning the measurement object 1 with the XY scanner 120.

The head 130 has an optical system capable of measuring vibration or deflection of the cantilever of the probe 110, and the optical system includes a laser generating unit 133 and a detector 134.

The laser generation unit 133 irradiates the surface of the cantilever of the probe 110 with a laser beam (shown by a dotted line), and the laser beam reflected from the surface of the cantilever is transmitted to a biaxial detector 134 such as a PSPD (Position Sensitive Photo Detector). It is reflected. A signal detected by such a detector 134 is sent to a controller 160 for control.

The AFM controller 160 is connected to the XY scanner 120 and the Z scanner 131 and controls the driving of the XY scanner 120 and the Z scanner 131. Further, the AFM controller 160 converts the signal obtained from the detector 134 into a digital signal using an ADC converter, and can utilize this to determine the degree of bending, twisting, etc. of the cantilever of the probe 110. A computer may be integrated into the AFM controller 160, or a separate computer and controller 160 may be connected. The AFM controller 160 may be integrated into one and placed in a rack, or may be divided into two or more pieces.

The AFM controller 160 sends a signal to drive the XY scanner 120 so that the object 1 to be measured can be scanned by the XY scanner 120 in the XY directions, while at the same time sending a signal to drive the XY scanner 120 so that the probe 110 has a constant mutual force with the surface of the object 1 to be measured (i.e. , the Z scanner 131 is controlled so that the cantilever maintains a certain degree of deflection, or so that the cantilever vibrates with a certain amplitude. That is, the AFM controller 160 has closed loop feedback logic, which may be software or electrical circuitry. The controller 160 may also measure the length of the Z scanner 131 (or the length of the actuator used in the Z scanner 131), or measure the voltage applied to the actuator used in the Z scanner 131. Then, topography data of the surface of the measurement object 1 is obtained.

Here, the tip of the probe 110 can also move relative to the surface of the measurement object 1 while in contact with the surface of the measurement object 1 (this is referred to as "contact mode"), or vibrate while not in contact with the surface. It is also possible to move relative to the surface of measurement object 1 while touching the surface of measurement object 1 (this is called "non-contact mode"), or to move relative to the surface of measurement object 1 while vibrating while hitting the surface of measurement object 1. (This is called "tapping mode"). These various modes correspond to previously developed modes, so a detailed description thereof will be omitted.

On the other hand, the data regarding the surface of the measurement target 1 obtained by the AFM controller 160 can be various in addition to the shape data. For example, data regarding the magnetic force on the surface of the measurement object 1, data regarding the electrostatic force, etc. can be obtained by floating a magnetic force on the probe 110 or performing special processing to apply an electrostatic force or the like. Modes of such an atomic microscope include magnetic force microscopy (MFM) and electrostatic force microscopy (EFM), which can be implemented using known methods. In addition, the data regarding the surface of the measurement object 1 may include surface voltage, surface current, and the like.

On the other hand, it should be noted that in the configuration of the head 130, only essential components are described for convenience of explanation, and specific configurations such as other optical systems are omitted. The structure disclosed in Registered Patent No. 10-0646441 may also be included.

<Configuration of an atomic microscope including an optical measurement device>
Hereinafter, embodiments of an atomic microscope including an optical measuring device of the present invention will be described with reference to the accompanying drawings.

FIG. 3 is a schematic front view of an atomic microscope including an optical measuring device according to an embodiment of the present invention, and FIG. 4 is a schematic diagram showing an atomic microscope including an optical measuring device according to another embodiment of the present invention. This is a schematic conceptual diagram of an atomic microscope viewed from the front.

For reference, FIGS. 3 and 4 are views of an atomic microscope including the optical measuring device of the present invention in the Y direction of FIG.

Referring to FIG. 3, the optical measurement device 200 includes an illumination section 210, a detection section 220, and an optical controller 230. For example, the optical measurement device 200 may be a scatterometer, regardless of the method of measuring an area or the method of measuring a spot. For example, a spectroscopic ellipsometer may be used as the optical measurement device 200.

The illumination unit 210 is configured to generate light and irradiate the measurement target 1, and may include a light source, a polarization/phase adjustment unit, and a lens, although not shown. That is, the illumination unit 210 generates light from a light source, adjusts polarization or phase, creates a desired beam shape using a lens, and irradiates the measurement object 1 with the light.

The light source of the illumination unit 210 can be appropriately selected depending on the measurement method to be applied, but to use a spectroscopic ellipsometer as an example, the light source emits light in a selected wavelength range (for example, 100 to 2500 nm). can be configured to generate.

Meanwhile, the illumination unit 210 may be configured so that light is incident on the measurement object 1 in the form of a spot, or may be configured so that light is incident on the measurement object 1 while forming an area.

The detection unit 220 is configured to receive light reflected from the surface of the measurement object 1. Although not shown, the detection unit 220 may include a polarization/phase adjustment unit and a slit unit. The detection unit 220 transmits information about the detected light to the optical controller 230.

The optical controller 230 uses the data obtained by the detection unit 220 to fit the shape of the structure on the surface of the measurement object 1. Optical controller 230 may include a computer system and may be integrated with AFM controller 160 described above and commonly referred to as a controller.

Optical measuring devices using the illumination unit 210 and the detection unit 220 include optical reflectometers, spectroscopic scatterometers, overlay scatterometers, angle-resolved beam profile reflectometers, and polarization-resolved beam profile reflectometers. A beam profile reflectometer, a beam profile reflectometer, a beam profile ellipsometer, an arbitrary angle or multi-wavelength ellipsometer, etc. can be applied without limitation.

The illuminating section 210 and the detecting section 220 cause light to enter the surface of the measurement object 1 obliquely so that the probe 110 is located between them. That is, the position measured by the optical measuring device 200 can be set close to the position measured by the atomic microscope 100.

However, the illumination unit 210 does not necessarily have to make the light incident on the surface of the measurement object 1 obliquely. For example, the optical measuring device may be configured in such a manner that the illumination unit 210 vertically illuminates the surface of the measurement object 1 from above the probe 110.

More preferably, the position measured by the optical measuring device 200 should match the position measured by the atomic microscope 100. Such matching can be achieved by moving the probe 110 relative to the surface of the measurement object 1 or by moving the optical measurement device 200 relative to the surface of the measurement object 1.

For example, the atomic microscope 100 includes an optical microscope (not shown) so that the probe 110 can be seen from above, and the position of the probe 110 can be identified through such an optical microscope, and light can be detected at the position of the probe 110. By adjusting the incident angle and position of the illumination unit 210 so that the light reflected from the surface of the measurement object 1 is reflected, and by adjusting the position of the detection unit 220 so that the light reflected from the surface of the measurement object 1 is received, the position measured by the optical measurement device 200 can be adjusted. can be matched to the position measured by the atomic microscope 100.

The incident angle of the light from the illumination unit 210 with respect to the surface of the measurement object 1 can be set in various ways, and it is preferable that the illumination unit 210 is configured so that the incident angle can be adjusted.

On the other hand, unlike FIG. 3, as shown in FIG. 4, the atomic microscope 100 and an optical measurement device 200 can also be arranged.

As shown in FIG. 4, when the optical measurement device 200 is installed in the atomic microscope 100 so that the offset A occurs, the angle of incidence through the illumination unit 210 can be set variously, and the angle of incidence through the illumination unit 210 can be set in various ways, and the angle of incidence can be set vertically. included. When the light is incident perpendicularly, the illumination unit 210 and the detection unit 220 may be formed of one member.

A control device (not shown) includes an AFM controller 160 and an optical controller 230, controls the operation of the atomic microscope 100 and the optical measurement device 200, and receives data obtained from the atomic microscope 100 and the optical measurement device 200.

The control device is controlled so that the position measured by the atomic microscope 100 and the position measured by the optical measurement device 200 can be matched with each other. For example, the control device moves the atomic microscope 100 or the optical measurement device 200 so that the position measured by the atomic microscope 100 and the position measured by the optical measurement device 200 are physically matched as shown in FIG. Each device can be controlled in a manner that allows Further, for example, the control device performs matching after the fact, taking into account the offset A, data obtained by measurements made by the atomic microscope 100 and the optical measurement device 200 at physically different measurement positions as shown in FIG. can be done. That is, matching may be physical matching or ex-post data matching that takes physical distance into consideration.

<Method of obtaining shape information of the surface to be measured using an atomic microscope including the above-mentioned optical measurement device>
FIG. 5 is a flowchart sequentially showing a method of obtaining shape information on the surface of a measurement object using an atomic microscope equipped with the optical measurement device of FIG. 3 or 4, and FIG. 6 shows an example of characteristic values. FIG.

First, in an atomic microscope measurement step (S110), shape information of a specific point on the surface of the measurement object 1 is obtained using the above-described atomic microscope 100. Here, the specific point can be a structure of a repeated pattern.

Thereafter, characteristic values for the shape are extracted (S120) using the shape information of the specific point obtained in the atomic microscope measurement step (S110). Referring to FIG. 6, the characteristic values for the shape are height, top width, bottom width, corner rounding radius (rounding 1, rounding 2), surface roughness, It may be at least one of a period and a sidewall angle (SWA).

In the optical measurement step (S130), shape information of a region including the specific point on the surface of the measurement object 1 is obtained using the optical measurement device 200 described above while referring to the characteristic value. At this time, measurement is performed by scanning the measurement object 1 using the XY scanner 120 of the atomic microscope 100.

FIG. 7 is a graph of a spectrum measured using an image of a physical model generated using a CD-SEM and characteristic values from the physical model, and FIG. 8 is a graph of a spectrum measured using an atomic microscope. 2 is a graph of an image generated from a physical model and a spectrum measured using characteristic values from the physical model.

First, referring to FIG. 7(a), when discretization is applied in the height direction to form a physical model of a repeated structure, considering the CD-SEM image, the blue line A physical model of a unit pattern having an outline as follows is defined. When applying the OCD (Optical Critical Dimension) methodology using the unit pattern of such a physical model, the actually measured n spectrum, c spectrum, and s spectrum (respectively (shown as blue, red, and green solid lines) and the theoretical value (or simulated value) (shown as circles, squares, and triangles). In other words, such a result indicates that the modeling is incorrect.

On the other hand, in this embodiment, n, c, and s are exemplified as measured values, but the present invention is not limited to these, and other measured values can also be used. For example, Psi, delta may be used, and Mueller matrix values may be used.

Such modeling errors can be caused by various factors. For example, it may be caused by a measurement error of the CD-SEM itself, or it may be caused by a difference between the point measured by the CD-SEM and the point measured by the optical measurement device. Of course, the two factors may act in combination.

Since it is not easy to match the measurement positions between the CD-SEM and the optical measurement device, modeling errors as shown in FIG. 7 are easily caused.

Such a problem can be solved by using a structure that allows measurement positions to be easily matched with each other, as in the apparatus of the present invention, where the measurement of the atomic microscope 100 and the measurement of the optical measurement device 200 are performed through the XY scanner 120 of the atomic microscope 100. It can be solved by choosing.

Referring to (a) of FIG. 8, the physical model (solid blue line discretized in the height direction) formed by the profile shape data (solid sky blue line) obtained by the atomic microscope 100 is shown in (a) of FIG. It has a somewhat different shape from a).

When the n-spectrum, c-spectrum, and s-spectrum are measured using such a physical model, it can be seen that they exactly match the theoretical values as shown in FIG. 8(b).

On the other hand, although n, c, and s have been described here as examples of measured values, the present invention is not limited to these, and other measured values may also be used. For example, Psi, delta may be used, and Mueller matrix values may be used.

To elaborate, the difference between FIG. 7 and FIG. This can be said to have occurred by applying the shape modeled in the OCD methodology.

When applying the OCD methodology as reliable characteristic values in this way, the number of variables to be measured can be reduced, thereby improving the precision and repeatability of predictions made by applying the OCD methodology.

FIG. 9 is a flowchart sequentially showing a method for obtaining shape information on the surface of a measurement target, which is different from the method shown in FIG.

Referring to FIGS. 3, 4, and 9, the optical measuring device 200 first measures a wide specific area (S210), the atomic microscope 100 measures a partial area (S220), and the measurement data by the optical measuring device 200 By combining the data measured by the atomic microscope 100 (S230), shape information on the surface of the measurement target can be obtained.

The partial area measured by the atomic microscope 100 may be a part of the specific area measured by the optical measurement device 200, or may be an area not included in the specific area.

The partial region to be measured with the atomic microscope 100 may be appropriately selected depending on the characteristics of the measurement object 1, but for example, it is better to select a structure having a complex and characteristic shape. Furthermore, the user may specify an area that he or she particularly wishes to confirm.

Since the atomic microscope 100 requires a relatively long measurement speed, after quickly measuring a wide area with the optical measurement device 200 having a fast measurement speed, a complex pattern is formed based on the measurement data by the optical measurement device 200. By identifying the position of the structure and performing measurement using the atomic microscope 100 at this position, it is possible to achieve high measurement speed while maintaining accuracy over a wide area.

<Method for measuring the physical properties of a measurement target based on the principle of localized surface plasmon resonance (LSPR) generation>
Localized surface plasmon resonance is a phenomenon in which when an electric field is applied to a metal nanostructure with a size smaller than the wavelength of light, a collective vibration phenomenon of electrons generated by the interaction between the electric field and conduction electrons of the metal at a specific wavelength occurs on the surface. This is a resonance phenomenon caused by Plurasmon. Localized surface plasmon resonance is greatly influenced by the size, morphology, and arrangement of metal nanostructures, the type of metal, and the surrounding environment.

FIG. 10 is a schematic front view of an atomic microscope including the optical measurement device of FIG. 3, which is operated to measure physical property values by localized surface plasmon resonance.

A localized surface plasmon resonance phenomenon can be induced from the configuration of an atomic microscope including the optical measurement device illustrated in FIG. 3, and thereby the characteristics of the object to be measured can be understood.

Referring to FIG. 10, unlike FIG. 3, the probe 110 is placed very close to the surface of the measurement object 1. The probe 110 only needs to be close to the surface of the measurement object 1 to the extent that it can be affected by the electric field amplified by localized surface plasmon resonance. For example, it is preferable that the probe 110 be set in a state in which it is interacting with the surface of the measurement target 1 in the above-described non-contact mode (this is generally referred to as an approach state). This utilizes the principle of measuring an electric field in a non-contact mode in an EFM (Electrostatic Force Microscopy) mode for measuring an electric field.

After the probe 110 approaches the surface of the measurement object 1 so that an electric field can be measured, the illumination section 210 is used to irradiate light (for example, a laser) between the probe 110 and the surface of the measurement object 1. At this time, the probe 110 is preferably coated with a metal such as gold to measure the electric field.

When irradiated with light, localized surface plasmon resonance occurs between the probe 110 and the surface of the measurement object 1. Specifically, when nano-sized metal nanoparticles are irradiated with light from a laser or a multi-wavelength light source, the energy of localized surface plasmon resonance is excited, and at this time, an electric field is induced within a certain range. The induced electric field shows a local electric field enhancement phenomenon near the metal nanoparticles. Such local electric fields are formed differently depending on the size, pattern, and arrangement of metal nanoparticles.

Such a local electric field affects not only the probe 110 but also the detection unit 220. That is, the local electric field causes a change in the behavior of the probe 110 to which the bias voltage is applied, and the characteristics of the local electric field can be measured using the EFM mode of a general atomic microscope. Of course, at this time, topography information can also be obtained. Additionally, additional information can be obtained by measuring the spectrum and intensity of the light reflected by the detection unit 220. In particular, since the chemical properties of a sample are closely related to the absorption spectrum of light, by measuring the absorption spectrum by localized surface plasmon resonance, it is possible to determine the nature of the surface substance of measurement object 1. In addition, by focusing on the fact that there are spectral components that are amplified by localized surface plasmon resonance, it is possible to obtain Raman spectral signals related to the intrinsic properties of a substance by amplifying them by localized surface plasmon resonance. In other words, the absorption spectrum due to the inherent properties of the substance on the surface of the measurement object 1 and the amplified Raman spectrum can be measured through the detection unit 220, and through this, the physical properties of the surface of the measurement object 1 can be determined.

The local electric field generated here can be generated by metal nanoparticles on the surface of the probe 110 and/or metal nanoparticles on the surface of the measurement object 1.

FIG. 11 is a flowchart of a method for obtaining information on the surface of a measurement target using the apparatus shown in FIG.

Referring to FIGS. 10 and 11, the method for obtaining information on the surface of a measurement target using an atomic microscope equipped with an optical measurement device includes the step of bringing the probe 110 of the atomic microscope close to the surface of the measurement target 1 (S310). ), a step (S320) of causing localized surface plasmon resonance (LSPR) by irradiating light between the probe and the surface of the measurement target using the illumination unit 210 of the optical measurement device; The method includes the steps of obtaining information about the measurement target from a probe that interacts with an electric field generated by resonance (S330), and obtaining a signal including at least an amplified Raman spectrum signal from the detection unit 220 of the optical measurement device (S340). .

The step of bringing the probe of the atomic microscope close to the surface of the measurement target (S310) can be performed by approaching the probe 110 in a non-contact mode. In addition, the step of obtaining a signal (S340) may further include obtaining a signal regarding an absorption spectrum.

Of course, the step of obtaining information from the probe 110 (S330) and the step of obtaining a signal from the detection unit 220 (S340) can be performed at the same time.

The atomic microscope that includes the optical measurement device of this embodiment, which utilizes localized surface plasmon resonance, can be used for quality measurement and defect analysis of nanopatterns formed or processed in the semiconductor manufacturing process, and for protein analysis. , measurement of properties of biomaterials such as cells, measurement of properties of gases/environment/chemicals, etc.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those with ordinary knowledge in the technical field to which the present invention pertains will be able to understand without changing the technical idea or essential features of the present invention. It will be appreciated that other specific forms may be implemented. Therefore, the embodiments described above should be understood to be illustrative in all respects and not limiting.

100: Atomic microscope 110: Probe 120: XY scanner 130: Head 131: Scanner 132: Probe arm 133: Laser generation unit 134: Detector 140: Stage 150: Fixed frame 160: AFM controller 200: Optical measurement device 210: Illumination section 220 :Detection unit 230: Optical controller

Claims (13)

an atomic microscope that scans the measurement object on an XY plane using an XY scanner that supports the measurement object and moves a probe along the surface of the measurement object to obtain characteristics of the surface of the measurement object;
An optical measurement device that includes an illumination unit that makes light enter the surface of the measurement target and a detection unit that detects light reflected from the surface of the measurement target, and obtains characteristics of the surface of the measurement target through scanning with the XY scanner. and,
Controlling the operation of the atomic microscope and the optical measurement device, receiving shape information of a specific point on the surface of the measurement target from the atomic microscope, and calculating characteristic values regarding the shape from the shape information of the specific point obtained from the atomic microscope. a control device that extracts shape information of a region including a specific point on the surface of the measurement target using the optical measurement device while referring to the characteristic value;
An atomic microscope equipped with an optical measurement device, wherein the control device is controlled so that a position measured by the atomic microscope and a position measured by the optical measurement device can be matched with each other. An atomic microscope equipped with the optical measuring device according to claim 1, wherein the illumination section is configured to make light incident near the probe. 3. An atom equipped with an optical measurement device according to claim 2, wherein the illumination section makes light obliquely incident on the surface of the measurement target so that the probe is located between the illumination section and the detection section. microscope. 3. The atomic microscope equipped with the optical measuring device according to claim 2, wherein the illumination unit is configured to vertically enter light from above the probe. By moving the probe with respect to the surface of the measurement target or moving the optical measurement device with respect to the surface of the measurement target, the position measured by the atomic microscope and the position measured by the optical measurement device An atomic microscope equipped with the optical measuring device according to claim 2, which is configured to be able to match the position. The atomic microscope and the optical measurement device are arranged such that an offset occurs between a position measured by the atomic microscope and a position measured by the optical measurement device. An atomic microscope equipped with an optical measuring device. An atomic microscope equipped with the optical measurement device according to claim 1, wherein the control device generates a physical model using shape information of a specific point on the surface of the measurement target obtained from the atomic microscope. . an atomic microscope that scans the measurement object on an XY plane using an XY scanner that supports the measurement object and moves a probe along the surface of the measurement object to obtain characteristics of the surface of the measurement object; An optical measurement device that includes an illumination unit that makes light enter the surface of the measurement target and a detection unit that detects light reflected from the surface of the measurement target, and obtains characteristics of the surface of the measurement target through scanning with the XY scanner. and a control device that controls the operation of the atomic microscope and the optical measurement device and receives data obtained from the atomic microscope and the optical measurement device, and the control device is configured to control the operation of the atomic microscope and the optical measurement device, and the control device A method of obtaining information on the surface of a measurement target using an atomic microscope equipped with an optical measurement device that is controlled to match a position with a position measured by the optical measurement device, the method comprising:
an atomic microscope measurement step of obtaining shape information of a specific point on the surface of the measurement target using the atomic microscope;
extracting characteristic values for the shape based on the shape information of the specific point obtained in the atomic microscope measurement step;
obtaining information on the surface of the measurement target using the optical measurement device while referring to the characteristic value; and an optical measurement step of obtaining shape information of a region of the surface of the measurement target including the specific point Method. 9. The characteristic value of the surface of the object to be measured according to claim 8 , wherein the characteristic value is at least one of height, top width, bottom width, corner rounding radius, surface roughness, period, and side wall angle (SWA). How to get information. A method for obtaining information on the surface of a measurement target using an atomic microscope equipped with the optical measurement device according to claim 1,
measuring a specific area with the optical measurement device;
A method for obtaining information on a surface of a measurement target, the method comprising the step of measuring a partial area with the atomic microscope based on measurement data by the optical measurement device. A method for obtaining information on the surface of a measurement target using an atomic microscope equipped with the optical measurement device according to claim 3,
bringing a probe of the atomic microscope close to the surface of the object to be measured;
causing localized surface plasmon resonance by irradiating light between the probe and the surface of the measurement target using an illumination unit of the optical measurement device;
obtaining information about the measurement target from the probe interacting with the electric field generated by the localized surface plasmon resonance;
obtaining a signal including at least an amplified Raman spectral signal from a detection section of the optical measurement device;
The probe is coated with metal, and the method obtains information about the surface of the object to be measured. 12. The method of obtaining information on a surface of a measurement target according to claim 11 , wherein the step of approaching is a step of approaching the probe in a non-contact mode. The method for obtaining information on a surface of a measurement target according to claim 11 , further comprising obtaining a signal regarding an absorption spectrum in the step of obtaining the signal.

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