KR101476808B1 - Scanner apparatus and atomic force microscope including the same - Google Patents

Abstract

The present invention relates to a scanner apparatus capable of preventing unnecessary resonance, and an atomic force microscope including the same. A scanner apparatus according to an embodiment of the present invention includes a fixing body which is fixed on the outside; a driving part which relatively moves with regard to the fixing body; an actuator which has one end supported by the fixing body and the other end operating the driving part; and a main connection part and a sub connection part which have a structure of flexure mechanism and connect the fixing body and the driving part. The main connection part and the sub connection part are positioned so that a change in the distance between the fixing body and the driving part according to the driving of the driving part in the position of the main connection part is greater than a change in the distance between the fixing body and the driving part according to the driving of the driving part in the position of the sub connection part.

Description

[0001] SCANNER APPARATUS AND ATOMIC FORCE MICROSCOPE INCLUDING THE SAME [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanner device and an atomic force microscope including the same, and more particularly, to a scanner device capable of preventing unnecessary resonance and increasing a resonance frequency, and an atomic force microscope including the same.

Scanning Probe Microscope (SPM) is a microscope that scans microscopic probes produced through MEMS processes, etc., and scans the surface of the specimens, and displays the 3D surface images of the specimens. Such a scanning probe microscope is subdivided into an AFM (Atomic Force Microscope), a Scanning Tunneling Microscope (STM), and the like depending on a measurement method. Since scanning to make relative movement between the probe and the sample is essential, Are commonly used.

[0003] As a scanner device, a tube scanner that uses a tube-shaped piezo to scan in the X and Y directions and feedback in the Z direction has been generally used. However, in the case of such a tube scanner, the movement in the X direction directly affects the movement in the Y direction in the correlation (coupling) between the movement in the X direction and the movement in the Y direction. As a result, the linearity of the XY scan can not be expected and there is a fatal disadvantage that accurate measurement data can not be obtained.

In order to solve these problems, an atomic microscope in which an XY scanner is constructed using a flexure structure and a Z scanner is separated therefrom has been developed (see Patent Document 1).

FIG. 1 is a schematic perspective view of an atomic microscope in which a conventional XY scanner and a Z scanner are separated, and FIG. 2 is a front view schematically showing the structure of the Z scanner of FIG.

1, the atomic force microscope 10 includes a cantilever 11 that follows a surface of a measurement target 1 in contact or noncontact state, an XY scanner (not shown) that scans an object to be measured in the XY plane in X and Y directions A Z scanner 13 connected to the cantilever 11 to move the cantilever 11 at a relatively small displacement in the Z direction and a Z scanner 13 connected to the cantilever 11 to move the cantilever 11 and the Z scanner 13 at a relatively large displacement Z And a stationary frame 15 for fixing the XY scanner 12 and the Z stage 14. The XY scanner 14 and the XY scanner 14 are fixed to each other.

The atomic force microscope 10 scans the surface of the measurement target 1 with the cantilever 11 to obtain an image such as a topography. The relative movement between the surface of the measurement target 1 and the cantilever 11 can be performed by the XY scanner 12. Moving the cantilever 11 up and down along the surface of the measurement target 1 can be performed by the Z scanner (13).

Referring to FIG. 2, the Z scanner 13 includes a fixed body 21, a driving unit 22 that moves relative to the fixed body 21, one end supported by the fixed body 21, And an actuator 23 for driving the driving part 22. The fixed body 21 and the driving part 22 are connected to each other through a connection part 24 of a flexure mechanism.

The fixed body 21 is fixedly mounted on the head (not shown) of the atomic force microscope 10 or the outer frame through the fixing hole 25 and the probe 22 for mounting the cantilever 11 The probe arm (16 in Fig. 1) is fixed. That is, the driving unit 22 can move the cantilever 11 up and down (that is, in the Z direction) through the probe arm 16.

When the length of the actuator 23 is increased, the driving plates 22 are moved to the lower side of FIG. 2 while the connecting plates of the connecting plates 24 are bent. When the length of the actuator 23 is decreased, The connecting plates are returned to the opposite side and the driving unit 22 is moved to the upper side of Fig.

The atomic force microscope 10 performs feedback by the Z scanner 13 such that the cantilever 11 has a constant interaction force (for example, Van der Waals force, magnetic force, etc.) with the surface of the measurement target 1 It is necessary to perform an XY scan on the surface of the object 1 to be measured by the XY scanner 12 so that the measurement speed is lower than other measurement devices such as an electron microscope have. When the speed of the XY scan is increased to overcome this, the Z scanner 13 must be capable of feedback at a high speed, and such quick feedback can be achieved by the vibration control of the Z scanner 13. [ In particular, when resonance occurs in the Z scanner 13, appropriate feedback can not be performed, so that a desired image can not be obtained.

Therefore, unnecessary resonance of the Z scanner 13 needs to be prevented. If resonance occurs, it is desirable to increase the resonance frequency as much as possible.

(Patent Document 1)

Korean Patent No. 10-0646441

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a scanner device which removes unnecessary resonance to enhance response characteristics and an atomic microscope using the same.

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

According to an aspect of the present invention, there is provided a scanner device including: a stationary body fixed to the outside; A driving unit that moves relative to the fixed body; An actuator having one end supported by the fixed body and the other end driving the driving unit; A main connection part and a sub connection part having a shape of a flexure mechanism and connecting the fixed body and the driving part; Wherein a variation amount of the distance between the fixed body and the driving part due to the driving of the driving part at the position of the main connection part is larger than a variation amount of the distance between the fixed body and the driving part due to the driving of the driving part at the position of the sub- The main connection part and the sub connection part are positioned so that the main connection part and the sub connection part are positioned.

According to another aspect of the present invention, the shape of the driving unit is a rectangle, the main connection unit is located at a side of the driving unit perpendicular to the driving direction of the driving unit, and the sub connection unit is parallel to the driving direction of the driving unit , And is located at a side of the driving unit.

According to another aspect of the present invention, the sub connection unit is formed of a coupling plate formed on each of two sides of the driving unit.

According to another aspect of the present invention, the connection plates are spaced apart from each other so as to be adjacent to edge portions of the driving unit.

According to another aspect of the present invention, the actuator is a stacked piezo, and a preload is applied to the driving unit in a direction opposite to the stretching direction of the laminated piezo.

According to another aspect of the present invention, a connection pin is interposed between the actuator and the fixed body, and between the actuator and the pin, and between the pin and the fixed body are in line contact with each other.

An atomic force microscope according to an embodiment of the present invention for solving the above-mentioned problems is characterized in that the above-described scanner device is used as a Z scanner and the cantilever is driven in the Z direction.

According to the scanner device of the present invention, unnecessary resonance can be prevented, and the vibration characteristic is excellent. Accordingly, the atomic microscope using such a scanner device can obtain an image such as a topography in a short period of time and obtain an image with low noise because the response characteristic is excellent even when high-speed scanning is performed.

1 is a schematic perspective view of an atomic force microscope in which a conventional XY scanner and a Z scanner are separated.
Fig. 2 is a front view schematically showing the structure of the Z scanner of Fig. 1;
3A and 3B are exploded perspective views of a Z scanner including a scanner device according to an embodiment of the present invention.
Figure 4 is a schematic front view of the scanner device of Figure 3;
Figure 5 is a schematic rear view of the scanner device of Figure 3;
FIGS. 6A and 6B are schematic rear views of a scanner device having a driving unit, a main connecting unit, and a sub-connecting unit, which are different from the scanner unit of FIGS.
FIG. 7 is a schematic perspective view of a Z scanner for explaining a vibration mode of the driving unit of FIG. 3. FIG.
FIGS. 8A and 8B are rear views of a scanner device in which the sub-connection portions of FIG. 5 are provided at different positions.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

It is to be understood that elements or layers are referred to as being "on " other elements or layers, including both intervening layers or other elements directly on or in between.

Although the first, second, etc. are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may be the second component within the technical scope of the present invention.

Like reference numerals refer to like elements throughout the specification.

The sizes and thicknesses of the individual components shown in the figures are shown for convenience of explanation and the present invention is not necessarily limited to the size and thickness of the components shown.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other partially or entirely and technically various interlocking and driving is possible as will be appreciated by those skilled in the art, It may be possible to cooperate with each other in association.

Hereinafter, a scanner device according to the present invention and an atomic force microscope using the same will be described with reference to the accompanying drawings.

The scanner device according to the present invention will be described below with reference to an example of the scanner device used in the Z scanner 13 of the atomic force microscope shown in FIG. 1, but the present invention is not limited thereto .

3 is an exploded perspective view of a Z scanner including a scanner device according to an embodiment of the present invention. FIG. 4 is a schematic front view of the scanner device of FIG. 3, and FIG. 5 is a schematic Respectively.

3A and 3B, the Z scanner 1000 includes a scanner device 100 and a probe arm 200. The Z-

The probe arm 200 can fix the cantilever at the end thereof and connect the cantilever and the driving unit 120 to move the cantilever up and down by the movement of the driving unit 120. The probe arm 200 is fitted to the driving unit 120 while being slid, and can be fixed by a plurality of bolts. The coupling between the probe arm 200 and the driving unit 120 may be performed by a known method, and thus a detailed description thereof will be omitted.

3A, 3B, 4 and 5, the scanner apparatus 100 of the present embodiment includes a fixed body 110, a driving unit 120, an actuator 130, a main connecting unit 140, A sub connection unit 150, and a preload device 160. [

The fixed body 110 surrounds the driving unit 120, which will be described later, and is fixed to the outside through a fixing hole 111 formed on the outer side. The fixed body 110 may be fixed to, for example, a head device. The head device includes a laser device and a photodiode sensor capable of measuring the degree of bending of the cantilever and may be a head device mounted on XE-100 or XE-150 of PARK SYSTEMS Co., Ltd., the applicant of the present specification . Detailed configuration of the head device can be found on the website of Park Systems Inc. (http://www.parkafm.com).

The driving unit 120 is located inside the fixed body 110. The driving unit 120 may be formed of the same material as the fixed body 110 and may be separated from the fixed body 110 by a thin through-hole 101 formed by laser processing, for example, 140 and the sub-connection unit 150. The sub-

In the central part of the driving part 120, a seating groove 121 in which the actuator 130 is seated is formed. A contact portion 122 is formed on the lower side of the seating groove 121 so as to contact one end of the actuator 130 and apply a force to the driving portion 120. The other end of the actuator 130 is disposed on the upper side of the seating groove 121 And a fixed body side contact surface 123 fixed to the fixed body 110 is formed via a connection pin 102 to be described later.

Meanwhile, the fixed body 110 and the driving unit 120 may be made of an alloy of SUS series, but the present invention is not limited thereto.

One end of the actuator 130 is in contact with the contact surface 122 of the drive portion and the other end of the actuator 130 is fixed to the contact surface 123 of the fixed body via the connection pin 102. [ As the actuator 130, a stacked piezo may be used, but it is not limited thereto, and any actuator can be used as long as it can generate a displacement in a straight line.

When the actuator 130 is extended, one end of the actuator 130 pushes the driving unit 120, and the driving unit 120 moves to the lower side of FIGS. 3A, 3B, 4, and 5. Accordingly, the cantilever connected by the driving unit 120 and the probe arm 200 can be moved downward.

On the other hand, the fixing method between the driving unit 120 and the probe arm 200 can be freely performed by a known method such as bolt fastening, adhesion, etc., and a detailed method is omitted in the present embodiment. In addition, the shape of the probe arm 200 may be variously set.

On the contrary, when the actuator 130 is contracted, the driving unit 120 is also moved upward due to the elasticity of the main connection unit 140 and the sub connection unit 150. However, since the force is not sufficient, It is difficult to return. Therefore, it is preferable to apply a preload applied to the driving unit 120 upward.

The preload device 160 is a device for applying a preload to the driving part 120 and comprises a bolt 161 and a preload spring 165 in this embodiment. The preload can be applied in the direction opposite to the direction in which the actuator 130 is extended by the preload spring 165. [

The other end of the actuator 130 is fixed to the fixed body 110 through the connection pin 102 to induce line contact between the actuator 130 and the fixed body 110. [ As described above, when a preload is applied to the actuator 130, which is a laminated piezoelectric actuator, hysteresis motion may occur, which can be mitigated by such line contact.

The main connecting part 140 connects the fixed body 110 and the driving part 120, and has a flexure structure, and two pieces are arranged on the upper and lower sides, respectively. The main connection part 140 utilizes the rigidity of the connection plate formed by laser machining or the like. The main connection part 140 provides the main elasticity in the upward and downward movement of the driving part 120 and guides the movement of the driving part 120.

In other words, the main connection portion 140 is located at a portion where the distance between the driving portion 120 and the fixed body 110 is varied by the driving of the actuator 130. In other words, the main connection part 140 is located on the side of the driving part 120 perpendicular to the driving direction of the driving part 120. That is, the main connection part 140 may be positioned in the driving direction of the driving part 120. As described above, the position of the main connection unit 140 can be determined, but the present invention is not limited thereto, and the positional relationship determined in relation to the sub connection unit 150 will be described later.

The sub connection unit 150 connects the fixed body 110 and the driving unit 150 in the same manner as the main connection unit 140. In the present embodiment, In other words, the sub connection unit 150 is located at a position where the distance between the driving unit 120 and the fixed body 110 does not vary. In other words, the driving unit 120, which is parallel to the driving direction of the driving unit 120, .

Meanwhile, the sub-connection unit 150 can be configured by the connection plate 151, and the interval d between the connection plates 151 can be variously set. The optimization of the interval d between the connection plates 151 will be described later.

FIGS. 6A and 6B are schematic rear views of a scanner device having a driving unit, a main connecting unit, and a sub connecting unit, which are different from the scanner unit of FIGS.

Referring to FIG. 6A, in the scanner device 100a according to another embodiment of the present invention, the driving unit 120a has a substantially hexagonal shape, and the main connection unit 140a has upper and lower sides and the sub connection unit 150a, One at each corner. Here, the pair of sub connection parts 150a may be located on the sides of the side part.

6B, in the scanner device 100b according to another embodiment of the present invention, the driving part 120b has an octagonal shape, and the main connection part 140b is positioned one by one on the upper and lower sides, 150b are positioned one on each side of the side.

Other configurations, that is, configurations of the fixed bodies 110a and 110b and the like are the same as those of the fixed body 110 of FIG. 3, and therefore, detailed description thereof will be omitted.

6A and 6B, the positions of the main connection parts 140a and 140b and the sub connection parts 150a and 150b are determined by the positions of the main connection parts 140a and 140b, The amount of distance between the driving units 120a and 120b and the driving units 120a and 120b is determined by the distance between the fixed bodies 110a and 110b driven by the driving units 120a and 120b and the driving units 120a and 120b at the positions of the sub- 120b, respectively. This is also applied to the scanner device 100 of FIG.

That is, the driving units 120a and 120b can be driven by only the main connecting units 140, 140a and 140b, and the sub connecting units 150, 150a and 150b are driven by the rotation of the driving units 120, 120a and 120b It is installed to prevent movement. This will be described later.

Hereinafter, improvement of the vibration characteristics of the scanner devices 100, 100a, and 100b having the above-described configuration will be described.

FIG. 7 is a schematic perspective view of a Z scanner for explaining a vibration mode of the driving unit of FIG. 3. FIG.

7, when the vibration mode of the driving unit 120 is largely divided, the driving unit 120 is rotated about the X axis (hereinafter, referred to as 'first mode') in which the driving unit 120 vibrates vertically (Hereinafter, referred to as a 'second mode') and a mode in which the driving unit 120 rotates and oscillates about the Z axis (hereinafter referred to as a 'third mode').

Here, the first mode can be alleviated or eliminated by the rigidity of the actuator 130 inserted into the scanner device 100, and by adjusting the magnitude of the preload applied to the driver 120 by the preload device 160 The resonant frequency can be adjusted. The second mode can also be mitigated by the preload applied to the driving unit 120. [ However, the degree to which the third mode is relaxed by the preload applied to the driving unit 120 is weak.

In order to prevent the vibration of the third mode, the present invention adopts the sub connection units 150, 150a and 150b. The sub connection portions 150, 250 and 350 relax the third mode by restricting the vibration of the third mode by the connection plate 151. [ Also, it is possible to adjust the resonance frequency of the third mode which is inevitably generated depending on how the sub connection portions 150, 150a, 150b are disposed.

FIGS. 8A and 8B are rear views of a scanner device in which the sub-connection portions of FIG. 5 are provided at different positions. The sub connecting portion 150 of FIG. 8A is disposed at a center portion of the driving portion 120 while keeping the connecting plate 151 at an interval smaller than the distance d between the connecting plates of FIG. 3, and the sub connecting portion 150 of FIG. The connecting plate 151 is held at an interval smaller than the distance d between the connecting plates of FIG.

A computer simulation was performed to determine which value the resonance frequency of the third mode has according to the arrangement of the sub connection portions 150. [ Here, the computer simulation can be performed by various programs, but the computer simulation is performed using the Ansys workbench.

When the sub connection unit 150 is located as shown in FIG. 5, the resonance frequency of the third mode is simulated at 19.9 kHz. 8A and 8B, while maintaining the same stiffness, i.e., elastic modulus, of the main connection portion 140 and maintaining the same thickness and length of the connection plate 151 of the sub connection portion 150, And other conditions such as material were kept the same, and then simulation was performed.

As a result, in the case of the driving unit 120 of the scanner device 100 'of FIG. 8A, the resonance frequency of the third mode is 15 kHz, and a lower resonance frequency value is simulated as compared with the scanner device 100 of FIG. 5 . In the case of the driving unit 120 of the scanner device 100 '' of FIG. 8B, the resonance frequency of the third mode is 12.5 kHz, and the scanner device 100 of FIG. 5 and the scanner device 100 'of FIG. The lowest resonance frequency value was simulated.

According to the computer simulation results described above, the positioning of the sub connection part 150 in either direction lowers the resonance frequency of the third mode, and the sub connection part 150 is positioned symmetrically with respect to the center of the driving part 120 The resonance frequency of the third mode is increased and the resonance frequency of the third mode is increased by increasing the interval.

When the scanner device according to the present invention is used as a Z scanner in the atomic microscope 10 in which the XY scanner 12 and the Z scanner 13 are separated as shown in FIG. 1, the scanning speed of the XY scanner 12 is increased Since it is necessary to increase the resonance frequency of the Z scanner 13 in order to increase the speed, it is preferable to dispose the sub connection unit 150 as shown in FIG. 3 to FIG. That is, it is preferable to dispose the connection plate 151 of the sub connection unit 150 adjacent to the edge of the driving unit 120 to widen the distance d.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

For example, although it is described in the present specification that a pair of sub-connection portions 150 are arranged on both sides, one sub-connection portion 150 may be disposed on either side, or only one sub-connection portion 150 may be disposed on either side. Conversely, three or more sub connection portions 150 may be disposed on both sides.

102 ... The connection pins 110, 110a, 110b ... Fixed body
120, 120a, 120b ... The driving unit 121 ... Seat groove
130 ... The actuators 140, 140a, 140b ... Main connection part
150, 150a, 150b ... Sub-connection 151 ... Connecting plate
160 ... Preload device 161 ... volt
165 ... Preload spring 200 ... Probe arm
100, 100a, 100b, 100 ', 100 " The scanner device
1000 ... Z Scanner

Claims (7)

A fixed body fixed to the outside;
A driving unit that moves relative to the fixed body;
An actuator having one end supported by the fixed body and the other end driving the driving unit; And
A main connection part and a sub connection part having a shape of a flexure mechanism and connecting the fixed body and the driving part; And it includes a
Wherein a distance variation amount between the fixed body and the driving unit according to the driving of the driving unit at the position of the main connection unit is larger than a variation amount of distance between the fixed body and the driving unit due to the driving of the driving unit at the position of the sub- Wherein the vibrating mode of the driving unit that rotates about an axis along the driving direction of the driving unit is relaxed by positioning the connection unit and the sub connection unit. The method according to claim 1,
The shape of the driving portion is a square,
Wherein the main connection part is located on a side of the driving part perpendicular to a driving direction of the driving part,
Wherein the sub-connection portion is located at a side of the driving portion, which is parallel to a driving direction of the driving portion. 3. The method of claim 2,
Wherein the sub connection unit comprises a connection plate formed on each of two sides of the driving unit. The method of claim 3,
Wherein the connecting plate is spaced apart from each other so as to be adjacent to a corner of the driving unit. The method according to claim 1,
The actuator is a stacked piezo,
Wherein a preload is applied to the driving unit in a direction opposite to the stretching direction of the laminated piezo. The method according to claim 1,
Wherein a connection pin is interposed between the actuator and the fixed body so that the actuator and the pin and the pin and the fixed body are in line contact with each other. An atomic force microscope characterized by driving the cantilever in the Z direction using the scanner device according to any one of claims 1 to 6 as a Z scanner.

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