KR102236590B1 - High-speed atomic force microscope - Google Patents

Abstract

A high-speed atomic force microscope is disclosed. A high-speed atomic force microscope according to the present invention comprises: a first scanner capable of adjusting displacement in a plane direction; A second scanner capable of adjusting a displacement in a direction perpendicular to the plane direction; and a displacement controlled by the first scanner and a displacement controlled by the second scanner may be independent of each other. The high-speed atomic force microscope according to the present invention further includes an objective lens for focusing a laser on a sample disposed on the first scanner, and the second scanner may be coupled to the objective lens through a coupling device. The first scanner may be physically separated from the second scanner, a groove in which the second scanner can be mounted may be formed on one side of the coupling device, and a side different from the side where the groove is formed in the coupling device The side surface may be formed to have a surface parallel to a surface on which the sample is disposed on the first scanner.

Description

High-speed atomic force microscope {HIGH-SPEED ATOMIC FORCE MICROSCOPE}

The present invention relates to a high-speed atomic force microscope.

A device that observes the surface of a sample using a very small probe is called a scanning probe microscope (SPM). Scanning probe microscopes are divided into scanning tunneling microscopes (STM) and atomic force microscopes (AFM), depending on how they are observed.

Atomic force microscope is a device made to compensate for the shortcomings of a scanning tunneling microscope.It is a device that can measure various properties including surface shape by using a micro-atomic interaction between the sample and the tip of the probe by bringing a fine probe close to the sample. to be. Contact mode for measuring by scratching the surface of a very small tip attached to the microscope's cantilever, tapping mode for measuring by tapping the surface of the tip, and non-contact measuring using van der Waals force between the tip and the atom. There is a non-contact mode.

1 is an example showing the structure of a scanner of a conventional high-speed atomic force microscope. More specifically, an X-Y-Z axis scanner in a conventional high-speed atomic force microscope is shown.

According to FIG. 1, in the conventional high-speed atomic force microscope, the AFM head and the scanner are provided in a separate structure, so that the XYZ axis scanner is provided as an integrated unit, or even if the XY axis scanner and the Z axis scanner are used separately, they are physically combined. The structure used in the form was used.

In the conventional high-speed atomic force microscope, there was a cross-coupling problem due to this. Cross coupling (cross talk) means that when displacement occurs in one axis, it is affected by the other axis as well. For example, in an XY-axis scanner, when a voltage is applied to the X-axis piezoelectric actuator, the actuator expands and the sample position area must be displaced only in the X-axis direction, but due to the cross-coupling problem, slight displacement occurs in the Y-axis. do.

In the X-Y-Z axis scanner in the conventional high-speed atomic force microscope, cross-coupling between the X, Y, and Z axes occurs. In other words, cross-coupling occurs between the X-Y axis, Y-Z axis, and X-Z axis. Accordingly, in the case of X-Y axis cross coupling, information in the lateral direction of the image may be distorted, and in the case of X-Z axis or Y-Z axis cross coupling, information in the height direction of the image may be distorted. This makes it difficult to accurately observe, and there is a problem in that an image distortion phenomenon exists.

In the present invention, it is intended to disclose a high-speed atomic force microscope capable of solving the cross-coupling problem.

In the present invention, it is intended to disclose a bonding structure of a high-speed atomic force microscope capable of solving the cross coupling problem.

In the present invention, it is intended to propose a coupling device capable of mounting a second scanner on a microscope.

The problem to be solved by the present invention is not limited to the problems mentioned above. Other technical problems not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

A high-speed atomic force microscope is disclosed.

A high-speed atomic force microscope according to an embodiment of the present invention includes: a first scanner capable of adjusting displacement in a plane direction; A second scanner capable of adjusting a displacement in a direction perpendicular to the plane direction; and a displacement controlled by the first scanner and a displacement controlled by the second scanner may be independent of each other.

The high-speed atomic force microscope further includes an objective lens for focusing a laser on a sample disposed on the first scanner, and the second scanner may be coupled to the objective lens through a coupling device.

The first scanner may be physically separated from the second scanner.

A groove in which the second scanner may be mounted may be formed on one side of the coupling device.

The coupling device may be formed to have a surface parallel to a surface on which the sample is disposed on the first scanner on a side other than the side where the groove is formed.

The second scanner may be configured to include a piezoelectric chip having a resonant frequency of 270 kHz or higher.

An AFM probe including a cantilever is mounted on the second scanner, and the AFM probe may have a mass adjusted so that the resonance frequency of the second scanner on which the AFM probe is mounted has a resonance frequency of 50 kHz or more.

The AFM probe may be provided to protrude from the coupling device.

In the present invention, a high-speed atomic force microscope and a bonding structure in which the cross-coupling problem is solved are disclosed, so that more accurate microscopic observation results can be obtained.

The effects of the present invention are not limited to the above-described effects. Effects not mentioned will be clearly understood by those of ordinary skill in the art from the present specification and the accompanying drawings.

1 is a perspective view showing the structure of a scanner of a conventional high-speed atomic force microscope.
2 is a side view of a high-speed atomic force microscope according to an embodiment of the present invention.
3 is a diagram showing the arrangement of optical elements of a high-speed atomic force microscope according to the present invention.
4(a) to 4(d) are views showing a coupling device and an AFM probe according to an embodiment of the present invention.
5 is a view for explaining a structure in which the coupling device is coupled to the high-speed atomic force microscope according to the present invention.
6(a) to 6(b) are views as viewed from the side of the bonding structure of the high-speed atomic force microscope of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in describing a preferred embodiment of the present invention in detail, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, the same reference numerals are used throughout the drawings for parts having similar functions and functions.

"Including" a certain component means that other components may be further included rather than excluding other components unless specifically stated to the contrary. Specifically, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features or It is to be understood that the presence or addition of numbers, steps, actions, components, parts, or combinations thereof does not preclude the possibility of preliminary exclusion.

Terms such as first and second may be used to describe various constituent elements, but the constituent elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer explanation.

1 is a diagram showing the structure of a scanner of a conventional high-speed atomic force microscope. As described above, in the conventional high-speed atomic force microscope, the XYZ axis scanner is not separated but provided as an integral unit, so that even when moving in one direction, accurate results can be obtained due to the cross-coupling phenomenon that is affected by the displacement in the other direction. There was a problem that could not be.

The high-speed atomic force microscope according to the present invention is configured to include a first scanner that generates displacement in a plane direction, and a second scanner that generates displacement in a direction perpendicular to the plane direction. 2 The displacement controlled by the scanner can be provided independently of each other, thereby improving the cross-coupling problem that existed in the previous high-speed atomic force microscope. The first scanner and the second scanner of the high-speed atomic force microscope according to the present invention are provided to be physically separated, and the second scanner may be coupled to the high-speed atomic force microscope through a separate coupling device. In this case, the first scanner may be an X-Y scanner, and the second scanner may be a Z scanner. The second scanner of the high-speed atomic force microscope according to the present invention is coupled to the objective lens through a separate coupling device, thereby obtaining a complete separation structure of the first scanner and the second scanner, whereby the first scanner and the second scanner are Can operate independently. The second scanner is configured to reduce unnecessary mass by being provided to include only a minimum number of parts, so that a high resonant frequency can be secured. For this reason, there is an effect of securing a high-speed scan of the second scanner.

Hereinafter, with reference to the drawings, the structure of the high-speed atomic force microscope according to the present invention will be described in detail. However, before describing the detailed structure in the following, a detailed description will be given of the field of application of the present invention.

The present invention relates to the structure of a high-speed atomic force microscope. This is somewhat different from the conventional atomic force microscope.

Conventional atomic force microscopes have a low bandwidth, and through closed-loop control, the displacement of the scanner can be measured and corrected in real time to enable accurate position movement, and operates at a scan speed of several Hz or less.

The high-speed atomic force microscope, which is the technical field of the present invention, has a high bandwidth and can operate at a scan speed of several hundred Hz or less.

In the scanners of the existing atomic force microscope, it is confirmed that the scanners are formed at the 3 kHz level even if the resonance frequency of the scanners is the highest. Therefore, in the conventional atomic force microscope, since the scan speed is limited by the resonance frequency, the scan is performed at a slower speed.

However, in the case of a scanner of a high-speed atomic force microscope, there is a difference in that it is confirmed that the resonance frequency of the X-Y scanner is provided at 5 kHz or more.

The maximum scan speed when scanning in an atomic force microscope can be affected by the width of the sample area to be scanned, the number of lines in the frame, and the feedback bandwidth. The maximum scan rate has a characteristic proportional to the feedback bandwidth, and the feedback bandwidth may be determined in consideration of all of a controller bandwidth and a detector bandwidth, a bandwidth of a Z-scanner, and a bandwidth of a cantilever.

In the case of the conventional atomic force microscope, the bandwidth is formed relatively small. According to an example, in the case of a voltage amplifier of a conventional atomic force microscope, the bandwidth is confirmed to be less than 50 kHz. On the other hand, the bandwidth of the voltage amplifier of the high-speed atomic force microscope is confirmed to be about 8 MHz.

In the aspect as described above, there is a difference between the conventional atomic force microscope and the high-speed atomic force microscope. The structure of the high-speed atomic force microscope according to the present invention will be described below on the premise that the present invention relates to a high-speed atomic force microscope capable of scanning at high speed.

2 is a view showing a side view of a high-speed atomic force microscope according to an embodiment of the present invention. The high-speed atomic force microscope according to the present invention may include a variety of components.

According to FIG. 2, the high-speed atomic force microscope includes a camera 1, an aspherical lens 2, a readout circuit 3, a PSPD 4, a first filter 5, a first beam splitter 6, and a first Mirror (7), second beam splitter (8), polarizing plate (9), second mirror (10), objective lens (11), coupling device (12), second scanner mount (13'), second scanner ( 13), an AFM probe mount 14', an AFM probe 14, and a first scanner 15.

It is obvious that the above embodiment corresponds to an embodiment of a high-speed atomic force microscope, and that one component can be replaced with another component having the same function. One component of the high-speed atomic force microscope may be provided with a change within the range that can be changed by a person skilled in the art. The role of each component included in the high-speed atomic force microscope can be described as follows.

Using the camera 1, the sample positioned on the first scanner 15 and the blue laser and the red laser in focus with the rear surface of the cantilever can be easily observed. This can be used for optical alignment. The camera 1 may be a CCD camera. An aspheric lens 2 may be mounted at a portion adjacent to the CCD camera 1. The aspherical lens 2 can form an image on the CCD camera 1.

The readout circuit (3) is used to convert the current signal from the photodiode into a voltage signal, and then calculate the signal and sum signal according to the degree of left/right deflection related to the AFM feedback function.

The position sensitive photo diode (PSPD) 4 may be a sensor used to detect a position of a red laser incident on the surface of the PSPD.

The first filter 5 has a cut-off wavelength of 550 nm. That is, wavelengths less than 550 nm can be blocked. The first filter may be a yellow filter. The first filter 5 may prevent unwanted light other than the reflected red laser from entering the PSPD 4.

The first beam splitter 6 splits the reflected and incoming red laser so that part of it is directed to the camera 1 and the rest is directed to the PSPD 4. The first beam splitter 6 may be glass. The first beam splitter 6 may be a non-polarizing beam splitter.

The first mirror 7 reflects the red laser and directs it in the direction of the PSPD 4.

The second beam splitter 8 splits the red laser into S-waves and P-waves. The second beam splitter 8 reflects the S wave and transmits the P wave from the spectroscopic red laser. The second beam splitter 8 may be a polarizing beam splitter.

The polarizing plate 9 serves to change the polarization direction of the red laser by 45 degrees. The S wave incident on the polarizing plate 9 passes through the polarizing plate 9 and then changes the polarization direction by 45 degrees and then goes toward the cantilever. After that, the red laser reflected by the cantilever and returned passes through the polarizing plate 9 again, and the polarization direction is changed by 45 degrees to change to a P wave. The changed P wave is transmitted from the second beam splitter 8 configured on the polarizing plate 9 and is directed toward the first mirror 7.

The second mirror 10 may be a dichroic mirror. The second mirror 10 has a property of reflecting or transmitting light of a specific wavelength. The second mirror 10 according to the present invention may pass the red laser and reflect the blue laser.

The objective lens 11 is used to focus the red laser and the blue laser. The two focused lasers are focused on the back of the cantilever. At this time, spots having a diameter of less than 40 micrometers may be formed.

The coupling device 12 may physically connect the second scanner 13 and the objective lens 11. The coupling device 12 may be equipped with a second scanner mount 13 ′, a second scanner 13, an AFM probe mount 14 ′, and an AFM probe 14. A second scanner mount 13 ′ may be mounted between the coupling device 12 and the second scanner 13. The AFM probe 14 may be composed of a holder 14a, a cantilever 14b, and a tip 14c. An AFM probe mount 14 ′ may be mounted between the AFM probe 14 and the second scanner 13. A more detailed structure of the coupling device 12 will be described later in FIG. 4.

The second scanner 13 may operate a fine displacement in the vertical direction to maintain a constant feedback parameter during operation of the high-speed atomic force microscope. The second scanner 13 may be a Z-axis scanner.

AFM probe (14) at the end of the cantilever A pointed tip 14c may be formed. The AFM probe 14 may interact with the sample through the tip 14c at the end of the cantilever 14b. The sample may be located on the upper surface of the first scanner 15.

The first scanner 15 may operate a fine displacement movement in a plane direction during scanning. The first scanner 15 may be an X-Y axis scanner.

As described above, a high-speed atomic force microscope can include a variety of components. Components characterized in the high-speed atomic force microscope according to the present invention will be additionally described below.

The readout circuit 3 according to the present invention can be set to have a high bandwidth. The readout circuit 3 according to the present invention may be set to have a bandwidth corresponding to the speed of a high-speed atomic force microscope. The readout circuit 3 is set to have a bandwidth corresponding to the speed of the high-speed atomic force microscope, thereby having the effect of processing the signal of the high-speed atomic force microscope more quickly.

The second scanner 13 according to the present invention may include a piezoelectric chip having a certain resonance frequency or more. The second scanner 13 may include a piezoelectric chip having a resonant frequency of 270 kHz or higher. The second scanner 13 may not include other components and may include only a piezoelectric chip.

When the mass of other elements coupled to the second scanner 13 increases, the resonant frequency of the second scanner 13 decreases. That is, as the mass of other elements coupled to the second scanner 13 decreases, the resonant frequency of the second scanner 13 increases, thereby enabling high-speed scanning.

The scan speed in the high-speed atomic force microscope may be affected by the mass of the AFM probe mount 14 ′ and the AFM probe 14 mounted under the second scanner 13. Therefore, the second scanner 13 in the high-speed atomic force microscope is required to reduce the mass to enable high-speed scanning.

Z-axis scanners in conventional atomic force microscopes are in the form of metal structures. Depending on the detailed model of the Z-axis scanner, it can be provided to have a resonant frequency of 2 to 3 kHz. A piezoelectric element may be mounted inside the Z-axis scanner of a conventional atomic force microscope. As an example of a commercially available Z-axis scanner of an atomic force microscope, the P-752.21C model may be used. In the P-752.21C model, a PICMA® P-885 piezoelectric actuator may be included and provided. The Z-axis scanner model is capable of a high displacement stroke and is equipped with a capacitive sensor, so that accurate position movement can be performed. However, the resonant frequency of the Z-axis scanner decreases due to the increase in mass generated from the structural aspect, and thus, it is not suitable for high-speed scanning.

In addition, components such as an AFM probe are additionally mounted on the outside of the Z-axis scanner, so that the resonance frequency is further lowered. This is suitable for general atomic force microscopy, but it is not suitable for high speed atomic force microscopy due to the low resonance frequency due to the mechanical structure.

In order to implement a high-speed atomic force microscope, all electronic equipment connected together with mechanical components must achieve high speed. In a high-speed atomic force microscope, the curve of the sample to be observed needs to be followed at a high speed, but if the Z-axis scanner is running slowly, the shape of the sample surface cannot be read properly. One of the problems in the prior art when driving the atomic force microscope at high speed is the feedback problem of the Z scanner.

That is, in a high-speed atomic force microscope, fast feedback control is required, and the resonance frequency of the cantilever must be sufficiently high in order to avoid the resonance phenomenon of the cantilever due to fast feedback.

The second scanner 13 of the high-speed atomic force microscope according to the present invention may include a piezoelectric chip having a resonant frequency of 270 kHz. In the second scanner 13 according to the present invention, by adjusting the mass of the AFM probe 14 and the AFM probe mount 14', the AFM probe 14 and the AFM probe mount 14' in the second scanner 13 It can have a resonant frequency of 50kHz or more when is mounted. Even if the AFM probe 14 and AFM probe mount 14' are mounted under the second scanner 13, the resonant frequency is constant by selecting the masses of the AFM probe 14 and AFM probe mount 14' as light as possible. High-speed scan can be secured by maintaining it above the level of resonant frequency. The resonant frequency of a certain level may be 50 kHz. In addition, a compact and simple structure can be secured by not adding a separate structure to the second scanner 13.

According to an embodiment of the present invention, the masses of the AFM probe mount 14 ′ and the AFM probe 14 may be measured as 549 mg. When the AFM probe mount 14' and the AFM probe 14 are mounted on a piezoelectric chip having a resonance frequency of 270 kHz, that is, under the second scanner 13, the resonance frequency decreases due to an increase in mass. Since the second scanner 13 is composed of only a piezoelectric chip, other mechanical structures are not mounted, and thus a high resonant frequency can be secured by itself, and additionally, the AFM probe 14 and the AFM probe mount 14' Even if is installed, high-speed scanning is possible by securing a resonant frequency of 50 kHz or more.

The second scanner 13 of the high-speed atomic force microscope according to the present invention has an effect of enabling rapid processing by being controlled by an open loop.

3 is a diagram showing optical elements for explaining how a sample can be observed by the high-speed atomic force microscope according to the present invention based on the components of the high-speed atomic force microscope described in FIG. 2. 3 schematically shows the components of the high-speed atomic force microscope according to FIG. 2. The first laser 20 and the second laser 30 may be applied respectively on the same height as the second beam splitter 8 and the second mirror 10. The first laser 20 may be a red laser. The second laser 30 may be a blue laser. The red laser is a laser with a wavelength of 635 nm and can be used for detection. The blue laser is a laser with a wavelength of 405 nm and can be used for excitation. The blue laser can force the cantilever to vibrate by utilizing the photothermal excitation property. When used in a contact mode, a red laser can be used, and when used in a non-contact mode and a tapping mode, both a red laser and a blue laser can be used.

Hereinafter, it is assumed that a sample is observed using a red laser. The red laser may apply a red laser toward the second beam splitter 8. The second beam splitter 8 speculates the red laser into S waves and P waves, and the S waves may be reflected in the direction of the polarizing plate 9. The red laser incident on the polarizing plate 9 may be applied toward the cantilever by changing the polarization direction by a predetermined angle. The second mirror 10 may pass the red laser and reflect the blue laser. The objective lens 11 focuses the red laser and blue laser applied from the second mirror 10 and forms a focus on the back side of the cantilever. The second scanner 13 and the first scanner 15 may adjust minute displacement during scanning using a cantilever.

The AFM probe 14 contacts the sample surface using a tip 14c located at the tip, or recognizes the sample using a non-contact mode or a tapping mode. Nuclear power between the atoms on the sample surface and the tip 14c attached to the end of the cantilever deflects the cantilever downward or upward, and the angular displacement of the cantilever deflects the angle of the laser beam reflected from the cantilever. By measuring the degree of deflection of the laser beam reflected from the cantilever with a photodiode (PSPD) 4, it is possible to find out the curvature of the sample surface.

4(a) to 4(c) are views showing an embodiment of the coupling device 12 according to the present invention. Fig. 4(a) is a side view of a coupling device 12 according to the invention. Fig. 4(b) is a cross-sectional view of the coupling device 12 of Fig. 4(a) taken along the B axis. Fig. 4(c) is a perspective view of a coupling device 12 according to the present invention. 4(d) is a perspective view of the AFM probe 14 according to the present invention.

For better understanding, the coupling device 12 in FIG. 4 includes a second scanner 13, a second scanner mount 13', an AFM probe mount 14', and an AFM probe in the coupling device 12 according to the present invention. (14) is shown combined. However, the coupling device 12 includes a second scanner 13, a second scanner mount 13', an AFM probe mount 14', and an AFM. It may be an object separate from the probe 14.

According to FIG. 4A, an upper groove having a diameter corresponding to the objective lens 11 may be formed so that the upper surface of the coupling device 12 may be coupled to the objective lens 11 in the form of a screw. An upper groove for physically coupling with the objective lens 11 may be formed on the upper surface of the coupling device 12. The diameter of the upper surface of the coupling device 12 may be configured to have a larger diameter than that of the objective lens 11. The coupling device 12 may be formed in a shape surrounding the objective lens 11 when forming a coupling structure with the objective lens 11.

A groove 120 into which the second scanner 13 can be mounted may be formed on the lower surface of the coupling device 12. The groove 120 formed on the lower surface of the coupling device 12 may be formed by being dug to a depth corresponding to a length in the vertical direction of the second scanner 13. The groove 120 formed on the lower surface of the coupling device 12 may be formed by being dug to a depth corresponding to the length of the second scanner 13 and the second scanner mount 13 ′ in the vertical direction. The depth of the groove 120 formed on the lower surface of the coupling device 12 may be a depth corresponding to a focal length of the objective lens.

Fig. 4(b) is a cross-sectional view of the coupling device 12 of Fig. 4(a) taken along the B axis. The coupling device 12 may be coupled to the objective lens 11 through a screw 16. A groove 120 may be formed on a lower surface of the coupling device 12, and a cut side surface 121 may be formed on a side adjacent to the groove 120 formed on the lower surface. The groove 120 formed on the lower surface of the coupling device 12 may be formed in either direction with respect to the central axis of the coupling device 12. The cut side surface 121 may be formed in a direction different from the side surface in which the groove 120 is formed based on the central axis of the coupling device 12.

The coupling device 12 may mount the second scanner 13 through the groove 120 formed on the lower surface. The groove 120 may be formed on the lower surface of the coupling device, and the second scanner 13 may be mounted on the groove 120 formed in the coupling device 12 to form a coupling structure.

The second scanner 13 may be connected to the coupling device 12 through the second scanner mount 13 ′. The second scanner mount 13 ′ is mounted on the innermost side of the groove of the coupling device 12, and may serve to connect the second scanner to the coupling device 12. The AFM probe mount 14 ′ may be mounted on the lower surface of the second scanner 13, and the AFM probe 14 may be coupled to the AFM probe mount 14 ′. An embodiment of the AFM probe 14 is shown in FIG. 4(d). According to FIG. 4D, the AFM probe 14 may include a holder 14a, a cantilever 14b, and a tip 14c. The AFM probe mount 14 ′ is connected to the AFM probe 14 to support and fix the AFM probe 14.

When the coupling device 12 is coupled to the objective lens 11, the cut one side 121 formed on the lower surface of the coupling device 12 is a sample on one side 121 and the first scanner 15. The disposed surfaces may be cut at an angle having a structure parallel to each other to be formed. In a state in which the coupling device 12 is coupled to the objective lens 11, by forming a coupling structure to have a surface 121 parallel to the surface on which the sample is placed on the first scanner 15, the first scanner 15 The distance to the sample located on the upper surface of the can be kept parallel.

Fig. 4(c) is a perspective view of a coupling device 12 according to the present invention. According to the perspective view of the coupling device 12 of FIG. 4C, the AFM probe 14 may be formed to protrude from the lower surface of the coupling device 12. According to the perspective view of the coupling device 12 of FIG. 4C, the second scanner 13 may be formed to protrude from the coupling device 12 by a certain portion. Alternatively, the second scanner 13 may be formed without protruding from the coupling device 12. Since the AFM probe 14 is formed to protrude toward the lower surface of the coupling device 12, the sample may be more easily accessed.

In the foregoing, Fig. 4 shows the structure of the coupling device 12 according to an embodiment of the present invention. However, one embodiment of the coupling device 12 is not limited thereto, and may be configured to couple the second scanner 13 to the objective lens 11, and when combined, complete separation from the first scanner 15 is achieved. If it is a structure, it may be designed in a range that can be changed at the level of knowledge of a person skilled in the art.

5 is a view for explaining a structure in which the coupling device 12 is coupled to the objective lens 11 in a high-speed atomic force microscope according to the present invention. The coupling device 12 according to the present invention may be coupled to the objective lens 11 through a screw method.

In the structure in which the coupling device 12 is coupled to the objective lens 11, the cut side 121 of the coupling device 12 is coupled at a position parallel to the surface on which the sample is placed on the first scanner 15. Can be. At the structural position where the coupling device 12 is coupled to the objective lens 11, the cut side 121 is compared with the groove 120 with respect to the central axis of the coupling device 12 as the first scanner 15 It can be located closer to the sample located on the image, The groove 120 may have a coupling structure so as to be positioned farther from the sample positioned on the first scanner 15 compared to the cut side 121. A criterion for determining a position closer to and further away from the sample may be determined based on a vertical distance between the sample and the cut side surface 121 and the sample and the groove 120.

That is, when viewed from the side, the coupling device 12 may be coupled to the objective lens 11 so that the vertical distance between the sample and the cut side 121 is closer than the vertical distance between the sample and the groove 120. When measuring the vertical distance between the sample and the groove 120, the distance between the sample and the surface on which the groove 120 is formed may be measured. In this case, it is assumed that the height of the sample when measuring the vertical distance to the sample is all constant.

When the coupling device 12 is coupled to the objective lens 11, the AFM probe mount 14' and the AFM probe 14 may be coupled to the lower portion of the second scanner 13 coupled to the groove 120. . The AFM probe 14 may include a holder 14a, a cantilever 14b, and a tip 14c. Of the end of the cantilever 14b The tip 14c may be formed to extend in a direction toward the sample.

According to an embodiment of the present invention, included in the AFM probe 14 under the second scanner 13 mounted on one side 121 of the coupling device 12 and the groove 120 of the coupling device 12 The vertical distance to the tip 14c of the cantilever may be 3.2 mm. In the present invention, the coupling device 12 on which the AFM probe 14 and the second scanner 13 are mounted is tightly coupled to the objective lens 11, so that the cantilever can be easily found through the monitor. In addition, optical alignment also has an easy effect.

6 is a side view of a high-speed atomic force microscope according to the present invention.

Figure 6 (a) is a view showing a high-speed atomic force microscope according to the present invention, Figure 6 (b) is a cross-sectional view of the high-speed atomic force microscope of Figure 6 (a) cut along the C axis. As shown in FIG. 6(b), in the high-speed atomic force microscope according to the present invention, due to the characteristics of the structure, the objective lens 11 may be provided while inclined at a predetermined angle with respect to an axis perpendicular to the first scanner 15. Since the coupling device 12 is coupled to the end of the inclined objective lens 11, when coupled, the coupling device 12 may be provided at an inclined angle with respect to an axis perpendicular to the first scanner 15. The coupling device 12 is coupled to the end of the objective lens 11 as described above, and the second scanner mount 13 ′ and the second scanner 13 are inserted into the groove 120 formed on the lower surface of the coupling device 12. ) Can be installed. The tip 14c of the AFM probe 14 mounted under the second scanner 13 may be formed to extend toward a position close to the position of the sample of the first scanner 15. One side 121 of the coupling device 12 may be formed to have an angle parallel to the first scanner 15. One side 121 of the coupling device 12 is formed to have an angle parallel to the first scanner 15 when it is coupled to the objective lens 11, thereby preventing unnecessary contact with the sample.

In the high-speed atomic force microscope according to the present invention, the cross-coupling problem between the first scanner 15 and the second scanner 13 is solved through a structure that completely separates the first scanner 15 and the second scanner 13. Can be solved. As a result, the cross-coupling problem between the first scanner 15 and the second scanner 13 is solved, but a cross-coupling problem on the first scanner 13 in which two axes coexist may remain. In the present invention, a cross-coupling problem on the first scanner 13 may be compensated by using a feedback circuit through computer coding.

It is to be understood that the above embodiments have been presented to aid understanding of the present invention, do not limit the scope of the present invention, and various deformable embodiments from this also fall within the scope of the present invention. The technical protection scope of the present invention should be determined by the technical idea of the claims, and the technical protection scope of the present invention is not limited to the literal description of the claims itself, but a scope that has substantially equal technical value. It should be understood that it extends to the invention of.

11: objective lens
12: coupling device
13: second scanner
13': 2nd scanner mount
14: AFM probe
14': AFM probe mount
15: first scanner

Claims (8)

A first scanner capable of adjusting displacement in a plane direction;
An objective lens for focusing a laser on a sample disposed on the first scanner;
Including; a second scanner capable of adjusting the displacement in a direction perpendicular to the plane direction;
The displacement controlled by the first scanner and the displacement controlled by the second scanner are independent of each other,
The second scanner is coupled to the objective lens through a coupling device,
The diameter of the upper surface of the coupling device is larger than the diameter of the lower surface of the objective lens, and an upper groove for physically coupling with the objective lens is formed on the upper surface of the coupling device,
The second scanner is a high-speed atomic force microscope mounted in a groove formed on a lower surface of the coupling device.
delete The method of claim 1,
The first scanner is a high-speed atomic force microscope, characterized in that the physical separation from the second scanner.
The method of claim 1,
A high-speed atomic force microscope in which the depth of the groove formed on the lower surface of the coupling device on which the second scanner is mounted is formed to a depth corresponding to a focal length of the objective lens.
The method of claim 1,
On the side where the groove is formed in the coupling device and on the other side
A high-speed atomic force microscope formed to have a plane parallel to a plane on which the sample is disposed on the first scanner.
The method according to any one of claims 3 to 5,
The second scanner is a high-speed atomic force microscope including a piezoelectric chip having a resonant frequency of 270 kHz or more.
The method of claim 6,
The second scanner is equipped with an AFM probe including a cantilever;
The AFM probe has a mass adjusted to have a resonant frequency of 50 kHz or more of a resonant frequency of the second scanner equipped with the AFM probe.
The method of claim 7,
The AFM probe is a high-speed atomic force microscope provided protruding from the coupling device.

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