JP2021060432A - Scanning probe microscope and probe contact detection method thereof - Google Patents

Abstract

To provide a scanning probe microscope capable of improving a phenomenon in which the value of the pressing force for detecting contact between a probe and a sample surface changes compared to a horizontal plane in the case when the sample surface that the probe contact is a slope.SOLUTION: The scanning probe microscope brings a probe into contact with the surface of a sample and scans the surface of the sample with the probe. The scanning probe microscope includes: a cantilever that has the probe at the tip; a displacement detection unit that detects a deflection amount and a twist amount of the cantilever; and a contact determination unit configured to determine a primary contact of the probe to the surface of the sample based on the deflection amount and twist amount in all directions in the cantilever detected by the displacement detection unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a scanning probe microscope and a probe contact detection method thereof.

Conventionally, the sample surface is continuously scanned on the sample surface while keeping the interaction between the sample and the probe formed at the tip of the cantilever (for example, the amplitude of the cantilever and the deflection of the cantilever) constant. A scanning probe microscope for measuring the uneven shape of a sample is known (see Patent Document 1). However, in the scanning probe microscope described in Patent Document 1, since the probe and the sample are always in contact with each other, the probe may be worn or the sample may be damaged.

On the other hand, in Patent Documents 2 and 3, the uneven shape of the sample surface is obtained by intermittently scanning the sample surface by bringing the probe into contact with the sample surface only at a plurality of preset measurement points on the sample surface. An intermittent measurement method has been proposed. In this method, when the force (deflection) applied to the cantilever exceeds a certain value, it is determined that the probe and the sample surface are in contact with each other, and the height of the probe when the probe is in contact with the sample is measured. As a result, in the intermittent measurement method, as compared with Patent Document 1, the probe and the sample surface are in contact with each other only at the measurement point, so that the minimum contact is required, and wear of the probe and damage to the sample can be reduced. ..

Japanese Unexamined Patent Publication No. 10-62158 Japanese Unexamined Patent Publication No. 2001-33373 Japanese Unexamined Patent Publication No. 2007-85764

However, the deflection of the cantilever is affected by the shape of the sample surface to be pressed in addition to the force by which the probe presses the sample surface (hereinafter referred to as "pressing force"). For example, when the surface of the sample with which the probe comes into contact is a slope, a larger pressing force may be required in order for the deflection of the cantilever to exceed a certain value, as compared with the horizontal plane. Therefore, when the sample surface, which is the measurement point, is a slope, the value of the pressing force for detecting the contact between the probe and the sample surface may change as compared with the horizontal plane. Therefore, an error may occur in the shape measurement on the slope of the sample surface, and the probe may be worn or the sample may be deformed. Such a problem is not limited to the intermittent measurement method, but is a problem common to measurement methods having a step of bringing the probe into contact with the sample surface.

The present invention has been made in view of such circumstances, and an object of the present invention is to make contact between the probe and the sample surface with respect to the amount of change in the value of the force generated when the sample surface with which the probe contacts is a slope. Scanning probe that can be improved by targeting not only deflection but also twist as the deformation of the cantilever to be detected, and then targeting all directions from no deformation to vertical deflection and left and right twist as the respective deformation directions. The present invention provides a microscope and a method for detecting contact with a probe thereof.

One aspect of the present invention is a scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe, the cantilever having the probe at the tip, and the amount of deflection and twist of the cantilever. A displacement detection unit that detects the above, and a contact determination unit that determines the primary contact of the probe with the sample surface based on the amount of deflection and the amount of twist in the cantilever detected by the displacement detection unit. , A scanning probe microscope.

One aspect of the present invention is a scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe, the cantilever having the probe at the tip, and the amount of deflection and twist of the cantilever. It is possible to determine the primary contact of the probe with the sample surface by using the displacement detecting unit for detecting the above and the value of the amount of deflection in the −Z direction in the cantilever detected by the displacement detecting unit. It is a scanning probe microscope including a contact determination unit.

Further, one aspect of the present invention is the scanning probe microscope described above, and the contact determination unit uses the probe when at least one of the deflection amount and the twist amount exceeds a predetermined range. Is in contact with the surface of the sample.

Further, one aspect of the present invention is the above-mentioned scanning probe microscope, which is a relative distance at which one of the probes is relatively moved with respect to the other when the probe and the surface of the sample are brought into contact with each other. A measuring unit for measuring a distance is further provided.

Further, one aspect of the present invention is the scanning probe microscope described above, in which the probe is retracted in a direction away from the sample after the relative distance is measured by the measuring unit, and the next measurement of the sample is performed. It further includes a moving drive unit that moves to a position.

Further, one aspect of the present invention is the scanning probe microscope described above, which further includes a unit for calculating the evacuation distance of the probe in the direction away from the sample based on the amount of deflection and the amount of twist.

Further, one aspect of the present invention is the scanning probe microscope described above, in which the moving drive unit moves to a measurement descending position located directly above the next measurement position that does not come into contact with the probe after the evacuation. , The probe is lowered from the measurement lowering position to the measurement position.

Further, one aspect of the present invention is the scanning probe microscope described above, wherein the amount of deflection detected by the displacement detection unit is within the first range, and the amount of twist is within the second range. A moving drive unit that scans with the probe is further provided.

Further, one aspect of the present invention is a probe contact detection method of a scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe, and the amount of deflection of the cantilever provided with the probe at the tip. A contact for determining the primary contact of the probe with the sample surface based on the displacement detection step for detecting the twist amount and the twist amount, and the omnidirectional deflection amount and the twist amount of the cantilever detected by the displacement detection step. It is a probe contact detection method of a scanning probe microscope including a determination step.

As described above, according to the present invention, when the sample surface with which the probe contacts is a slope, the value of the pressing force for detecting the contact between the probe and the sample surface changes as compared with the horizontal plane. It is possible to provide a scanning probe microscope and a method for detecting probe contact thereof, which can be improved.

It is a figure which shows an example of the schematic structure of the scanning probe microscope 1 in this embodiment. It is a perspective view of the sample S having a slope in this embodiment, and the cantilever 2. It is a figure explaining the 1st range and the 2nd range in this embodiment. It is a plan view of the dome-shaped sample S in this embodiment, and is the figure which shows the measurement point (1)-(7) of the shape measurement of a sample S. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (1) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (2) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (3) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (4) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (5) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (6) of the sample S in this embodiment. It is a figure which shows the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (7) of the sample S in this embodiment. It is a figure which shows the flow of the contact detection process which detects the contact between the probe 2a and the surface of a sample S in the control device 7 of this embodiment. It is a figure which shows the flow of another example of the contact detection process which detects the contact between the probe 2a and the surface of a sample S in the control device 7 of this embodiment.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the inventions that fall within the scope of the claims. Also, not all combinations of features described in the embodiments are essential to the means of solving the invention. In the drawings, the same or similar parts may be designated by the same reference numerals to omit duplicate explanations.

The scanning probe microscope in the embodiment scans the sample surface by bringing the probe into contact with the sample surface, and whether or not the probe has come into contact with the sample surface based on the amount of deflection and the amount of twist of the probe. Is determined. Hereinafter, the scanning probe microscope of the embodiment will be described with reference to the drawings.

FIG. 1 is a diagram showing an example of a schematic configuration of the scanning probe microscope 1 of the present embodiment. As shown in FIG. 1, the scanning probe microscope 1 includes a cantilever 2, a sample table 4, a moving drive unit 5, a displacement detection unit 6, and a control device 7.

The cantilever 2 includes a probe 2a at its tip. The base end of the cantilever 2 is fixed, and the tip is a free end. The cantilever 2 is an elastic lever member having a small spring constant K, and when the probe 2a at the tip comes into contact with the surface of the sample S, the probe 2a at the tip bends according to the pressing force pressing the surface of the sample S. .. Further, when the cantilever 2 comes into contact with the probe 2a at the tip and the surface of the sample S, if the surface of the sample S has an inclination, the inclination and the inclination of the probe 2a at the tip and the surface of the sample S Twisting and bending occur according to the fulcrum reaction force of the fulcrum, which is the contact point. One of the features of the scanning probe microscope 1 in the present embodiment is the deflection and twist of the cantilever 2 caused by the contact between the probe 2a at the tip and the surface of the sample S, and the surface of the probe 2a and the sample S. It is in the place to detect the contact of.

The mobile drive unit 5 includes a Z-direction drive device 22 and an XY scanner 25.
A cantilever 2 is attached to the lower end of the Z-direction drive device 22, and the cantilever 2 is moved in a direction perpendicular to the horizontal plane (Z direction). For example, the Z-direction drive device 22 is a piezoelectric element. The Z-direction drive device 22 brings the cantilever 2 closer to the surface of the sample S or retracts (or detaches) the cantilever 2 from the surface of the sample S based on the first drive signal output from the control device 7. However, the Z-direction drive device 22 and the XY scanner 25 are arranged as long as they can be relatively scanned for three-dimensional shape observation, such as an arrangement integrated with the sample side or an arrangement integrated with the cantilever side. The relationship does not matter.

A sample table 4 is placed on the XY scanner 25. The sample S is placed on the sample table 4 so as to face the probe 2a of the cantilever 2. When the second drive signal is output from the control device 7, the XY scanner 25 moves the probe 2a and the sample S relative to the XY direction according to the voltage value and polarity of the second drive signal. Let me. In FIG. 1, the plane parallel to the surface of the sample table 4 is a horizontal plane, and here, it is defined as an XY plane by the two orthogonal axes X and Y.

The displacement detection unit 6 detects the amount of deflection and the amount of twist of the cantilever 2. In the present embodiment, the case where the displacement detection unit 6 detects the amount of deflection and the amount of twist of the cantilever 2 by using the optical lever type will be described.
The displacement detection unit 6 includes a light irradiation unit 31 and a light detection unit 33.
The light irradiation unit 31 irradiates the laser beam L1 on a reflective surface (not shown) formed on the back surface of the cantilever 2.

The photodetector 33 receives the laser beam L2 reflected by the reflecting surface. The photodetector 33 is a photodetector provided with a quadrant light receiving surface 27 that receives the laser beam L2 reflected on the back surface. That is, the laser beam L2 reflected by the back surface of the cantilever 2 adjusts the optical path (usually near the center of the light receiving surface 27) so as to be incident on the plurality of light receiving surfaces 27 divided into four by the photodetector 33. To do. Hereinafter, a method for detecting the amount of deflection and the amount of twist of the cantilever 2 in the present embodiment will be described with reference to FIGS. 1 and 2.
FIG. 2 is a perspective view of the sample S having a slope and the cantilever 2.

When the probe 2a and the surface of the sample S come into contact with each other, the cantilever 2 is displaced in either one or both of the Z direction and the Y direction. In the present embodiment, the displacement of the cantilever 2 that occurs in the Z direction is referred to as the amount of deflection, and the displacement of the cantilever 2 that occurs in the Y direction is referred to as the amount of twist. For example, in the initial condition, the incident spot position on the light receiving surface 27 of the photodetector 33 of the laser beam L2 reflected in the state where no force is applied to the probe 2a is set as the center position of the light receiving surface 27. The state in which no force is applied to the probe 2a is, for example, a state in which the cantilever in which the probe 2a and the surface of the sample S are not in contact is not deformed.

In the contact mode, when the probe 2a and the surface of the sample S come into contact with each other, a force is applied to the probe 2a, so that the cantilever 2 is bent or twisted. Therefore, the position of the reflection spot of the laser beam L2 reflected on the back surface of the cantilever 2 in which the amount of deflection and the amount of twist are generated is displaced from the center position thereof. Therefore, the scanning probe microscope 1 can detect the magnitude and direction of the force applied to the probe 2a by capturing the moving direction of the spot position on the light receiving surface 27 of the photodetector 33. For example, in FIG. 1, when a twist amount is generated in the cantilever 2, the change in the spot position in the α direction can be captured on the light receiving surface 27 of the photodetector 33. Further, when the amount of deflection occurs in the cantilever 2, the light receiving surface 27 can capture the change in the spot position in the β direction. The amount of change in the spot position from the center position depends on the amount of twist and the amount of deflection. Further, when the cantilever 2 is bent in the + Z direction, the reflection spot of the laser beam L2 on the light receiving surface 27 of the photodetector 33 changes in the + β direction. Further, when the cantilever 2 is bent in the −Z direction, the reflection spot of the laser beam L2 on the light receiving surface 27 of the photodetector 33 changes in the −β direction. On the other hand, when the cantilever 2 is twisted in the + Y direction, the reflection spot position of the laser beam L2 on the light receiving surface 27 of the photodetector 33 changes in the + α direction. When the cantilever 2 is twisted in the −Y direction, the reflection spot of the laser beam L2 on the light receiving surface 27 of the photodetector 33 changes in the −α direction.

The photodetector 33 outputs a first detection signal corresponding to the position of the reflection spot of the laser beam L2 in the ± Z direction of the light receiving surface 27 to the control device 7. That is, the first detection signal is a DIF signal (deflection signal) corresponding to the amount of deflection of the cantilever 2. Further, the photodetector 33 outputs a second detection signal corresponding to the position of the reflection spot of the laser beam L2 in the ± Y direction of the light receiving surface 27 to the control device 7. That is, the second detection signal is an FFM signal (twist signal) corresponding to the amount of twist of the cantilever 2.

As shown in FIG. 1, the control device 7 includes a contact determination unit 42, a drive unit 43, and a measurement unit 44.
The contact determination unit 42 determines whether or not the probe 2a has come into contact with the surface of the sample S based on the first detection signal and the second detection signal output from the light detection unit 33. That is, the contact determination unit 42 determines whether or not the probe 2a has come into contact with the surface of the sample S based on the amount of deflection and the amount of twist of the cantilever 2.

The contact determination unit 42 includes a first determination unit 421 and a second determination unit 422.
The first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S when the amount of deflection indicated by the first detection signal output from the light detection unit 33 exceeds the first range. When the first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S, the first determination unit 421 outputs a first contact signal indicating that the probe 2a has come into contact with the surface of the sample S to the drive unit 43.

The second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S when the amount of twist indicated by the second detection signal output from the light detection unit 33 exceeds the second range. When the second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S, the second determination unit 422 outputs a second contact signal indicating that the probe 2a has come into contact with the surface of the sample S to the drive unit 43. As described above, the contact determination unit 42 has the first condition that the amount of deflection indicated by the first detection signal output from the light detection unit 33 exceeds the first range, and the second detection signal output from the light detection unit 33. When at least one of the second conditions in which the twist amount indicated by the above exceeds the second range is satisfied, it is determined that the probe 2a has come into contact with the surface of the sample S. In the above, the first detection signal and the second detection signal are determined independently, but in the contact determination unit 42, "square of the first detection signal" and "square of the second detection signal". , And the positive number of the square root of the sum is determined to be in contact when the value exceeds a certain level.

Hereinafter, the first range and the second range in the present embodiment will be described with reference to FIG. FIG. 3 is a diagram illustrating a first range and a second range in the present embodiment.

As shown in FIG. 3, the first range includes a deflection upper limit threshold and a deflection lower limit threshold. The upper limit of the deflection is the amount of deflection of the cantilever 2 that is deflected in the + Z direction due to the contact between the surface of the probe 2a and the sample S. On the other hand, the lower limit of deflection is the amount of deflection of the cantilever 2 that is deflected in the −Z direction due to the contact between the surface of the probe 2a and the sample S. Therefore, in the first determination unit 421, when the amount of deflection indicated by the first detection signal output from the light detection unit 33 exceeds the upper limit value of the deflection, or the amount of deflection indicated by the first detection signal falls below the lower limit value of the deflection. In this case, it is determined that the probe 2a has come into contact with the surface of the sample S.

The second range includes a twist upper limit threshold and a twist lower limit threshold. The upper limit of twist is the amount of twist of the cantilever 2 twisted in the + Y direction due to the contact between the surface of the probe 2a and the sample S. On the other hand, the lower limit of twist is the amount of twist of the cantilever 2 twisted in the −Y direction due to contact between the probe 2a and the surface of the sample S. Therefore, in the second determination unit 422, when the twist amount indicated by the second detection signal output from the light detection unit 33 exceeds the twist upper limit value, or the twist amount indicated by the second detection signal falls below the twist lower limit value. In this case, it is determined that the probe 2a has come into contact with the surface of the sample S. In this way, in the two-dimensional coordinates of the amount of deflection and the amount of twist shown in FIG. 3, the positions indicated by the amount of deflection indicated by the first detection signal and the amount of twist indicated by the second detection signal are in the range indicated by diagonal lines. When the probe 2a is located outside the sample S, it is determined that the probe 2a has come into contact with the surface of the sample S.

Hereinafter, a method for determining the contact between the probe 2a and the surface of the sample S in the present embodiment will be described. FIG. 4 is a plan view of the dome-shaped sample S, and is a diagram showing positions where the probe 2a and the surface of the sample S come into contact with each other, that is, measurement points (1) to (7) for shape measurement of the sample S.

FIG. 5 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (1) of the sample S in the present embodiment. FIG. 5A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (1), and FIG. 5B shows the probe 2a at the measurement point (1). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 5 (c) shows a side view of the cantilever 2 as seen from the −Y direction in a state where the probe 2a comes into contact with the measurement point (1) and then further pushed in, and FIG. 5 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 1) and then pushed further is shown.

As shown in FIGS. 5A and 5B, in the primary contact state in which the probe 2a is in contact with the measurement point (1), the cantilever 2 is slightly deflected, but the measurement point (1) Since the surface of the surface is not tilted (horizontal), no twist amount is generated. Further, as shown in FIGS. 5 (c) and 5 (d), in the secondary contact state in which the probe 2a is pressed against the measurement point (1) from the state in which the probe 2a is in contact, the cantilever 2 has a deflection amount corresponding to the pressing force. appear. However, since the surface of the measurement point (1) is not tilted, no twist amount is generated. Therefore, the contact determination unit 42 determines whether or not the probe 2a has come into contact with the surface of the sample S based on whether or not the amount of deflection indicated by the first detection signal exceeds the upper limit of the deflection.

FIG. 6 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (2) of the sample S in the present embodiment. FIG. 6A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (2), and FIG. 6B shows the probe 2a at the measurement point (2). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 6 (c) shows a side view of the cantilever 2 as viewed from the −Y direction in a state where the probe 2a comes into contact with the measurement point (2) and then is further pushed in, and FIG. 6 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 2) and then pushed further is shown.

As shown in FIGS. 6A and 6B, in the primary contact state in which the probe 2a is in contact with the measurement point (2), the cantilever 2 is placed on the surface of the sample S by a normal force corresponding to the pressing force. A amount of deflection in the −Z direction corresponding to the force for tilting the probe 2a and the pressing force is generated in the vertical axial direction. However, since the surface of the measurement point (2) has no inclination in the ± Y direction, no twist amount is generated. On the other hand, as shown in FIGS. 6 (c) and 6 (d), in the case of a secondary contact state in which the probe 2a is pressed against the measurement point (2) from the state in which the probe 2a is in contact with the measurement point (2), the pressing force of the cantilever 2 is deflected by the normal force. When the force that generates the amount is exceeded, the bending direction changes, and the amount of bending in the + Z direction is generated. However, since the surface of the measurement point (2) has no inclination in the ± Y direction, no twist amount is generated.

The conventional scanning probe microscope determines that the probe 2a has come into contact with the surface of the sample S only when the amount of deflection in the + Z direction exceeds a certain value. Therefore, in the conventional scanning probe microscope, the amount of deflection is generated in the −Z direction in the primary contact state (FIGS. 6A and 6B) in which the probe 2a is in contact with the measurement point (2). , The contact between the probe 2a and the sample S cannot be determined. Therefore, the conventional scanning probe microscope presses the sample S with a larger pressing force, and the probe 2a is in a secondary contact state in which the cantilever 2 is bent in the + Z direction (FIGS. 6 (c) and 6 (d)). The contact between the sample S and the sample S will be determined. Therefore, the probe 2a may be worn or the sample S may be deformed. Since the scanning probe microscope 1 of the present embodiment determines that the probe 2a has come into contact with the surface of the sample S when the amount of deflection of the cantilever 2 exceeds the first range, the probe 2a is determined to be in contact with the surface of the sample S. The primary contact state between the sample S and the sample S can be determined. Therefore, wear of the probe 2a and deformation of the sample S can be suppressed.

FIG. 7 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (3) of the sample S in the present embodiment. FIG. 7A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (3), and FIG. 7B shows the probe 2a at the measurement point (3). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 7 (c) shows a side view of the cantilever 2 as viewed from the −Y direction in a state where the probe 2a comes into contact with the measurement point (3) and then is further pushed in, and FIG. 7 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 3) and then pushed further is shown.

As shown in FIGS. 7A and 7B, when the probe 2a comes into contact with the measurement point (3), the cantilever 2 is subjected to a vertical drag corresponding to the pressing force in the axial direction perpendicular to the surface of the sample S. In addition, the amount of deflection in the + Z direction corresponding to the force for tilting the probe 2a and the pressing force is generated. However, since the surface of the measurement point (3) has no inclination in the ± Y direction, no twist amount is generated. On the other hand, as shown in FIGS. 7 (c) and 7 (d), when the probe 2a is pressed against the measurement point (3) from the state of being in contact with the measurement point (3), the cantilever 2 generates a deflection amount according to the pressing force. However, since the surface of the measurement point (3) has no inclination in the ± Y direction, no twist amount is generated. Therefore, the contact determination unit 42 determines whether or not the probe 2a has come into contact with the surface of the sample S based on whether or not the amount of deflection indicated by the first detection signal exceeds the upper limit of the deflection.

FIG. 8 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (4) of the sample S in the present embodiment. FIG. 8A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (4), and FIG. 8B shows the probe 2a at the measurement point (4). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 8 (c) shows a side view of the cantilever 2 as seen from the −Y direction in a state where the probe 2a comes into contact with the measurement point (4) and then further pushed in, and FIG. 8 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 4) and then pushed further is shown.

As shown in FIGS. 8A and 8B, when the probe 2a comes into contact with the measurement point (4), the cantilever 2 generates a slight amount of deflection, and the vertical drag corresponding to the pressing force causes the cantilever 2 to bend in the + Y direction. A twist amount is generated. This is because the surface of the sample S at the measurement point (4) has an inclination in the + Y direction. Further, as shown in FIGS. 8 (c) and 8 (d), when the probe 2a is pressed against the measurement point (4) from the state of being in contact with the measurement point (4), the cantilever 2 generates a deflection amount corresponding to the pressing force and the pressing force. The amount of twist in the + Y direction is generated by the normal force corresponding to.

Here, the amount of deflection generated in the cantilever 2 is affected by the inclination of the surface of the sample S to be pressed in addition to the pressing force. For example, when the surface of the sample S with which the probe 2a comes into contact is a slope, a larger pressing force is required in order for the amount of deflection of the cantilever 2 to exceed a certain value, as compared with a horizontal plane. Therefore, when the measurement point (1) and the measurement point (4) are compared, a larger pressing force is required to generate the same amount of deflection as the measurement point (1).

In the conventional scanning probe microscope, the constant value is set to the amount of deflection when the probe 2a comes into contact with the measurement point (1). This is because in the conventional scanning probe microscope, the deflection of the cantilever 2 is set to be constant. Therefore, in the conventional scanning probe microscope, the contact between the probe 2a and the sample S cannot be detected in the state where the probe 2a is in contact with the measurement point (4) (FIGS. 8A and 8B). Therefore, the conventional scanning probe microscope presses the sample S with a larger pressing force, and when the amount of deflection in the −Z direction to the extent that the cantilever 2 exceeds a certain value is generated, the probe 2a and the sample S come into contact with each other. It will be detected (FIGS. 8 (c) and 8 (d)). Therefore, the probe 2a may be worn or the sample S may be deformed. The scanning probe microscope 1 of the present embodiment can detect the contact between the probe 2a and the sample S based on the amount of twist of the cantilever 2. That is, in the scanning probe microscope 1, when the probe 2a comes into contact with the measurement point (4) having a slope (FIGS. 8A and 8B), the probe 2a and the sample S are based on the amount of twist of the cantilever 2. Contact with can be detected. Therefore, wear of the probe 2a and deformation of the sample S can be suppressed.

FIG. 9 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (5) of the sample S. FIG. 9A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (5), and FIG. 9B shows the probe 2a at the measurement point (5). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 9 (c) shows a side view of the cantilever 2 as viewed from the −Y direction in a state where the probe 2a comes into contact with the measurement point (5) and then is further pushed in, and FIG. 9 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 5) and then pushed further is shown.

As shown in FIGS. 9A and 9B, when the probe 2a comes into contact with the measurement point (5), the cantilever 2 generates a slight amount of deflection, and the vertical drag corresponding to the pressing force causes the cantilever 2 to bend in the + Y direction. A twist amount is generated. This is because the surface of the sample S at the measurement point (5) has an inclination in the −Y direction. Further, as shown in FIGS. 9 (c) and 9 (d), when the probe 2a is pressed against the measurement point (5) from the state of being in contact with the measurement point (5), the cantilever 2 generates a deflection amount corresponding to the pressing force and the pressing force. The amount of twist in the -Y direction is generated by the normal force corresponding to.

Here, the amount of deflection generated in the cantilever 2 is affected by the inclination of the surface of the sample S to be pressed in addition to the pressing force. For example, when the surface of the sample S with which the probe 2a comes into contact is a slope, a larger pressing force is required in order for the amount of deflection of the cantilever 2 to exceed a certain value, as compared with a horizontal plane. Therefore, when the measurement point (1) and the measurement point (5) are compared, a larger pressing force is required to generate the same amount of deflection as the measurement point (1).

In the conventional scanning probe microscope, the constant value is set to the amount of deflection when the probe 2a comes into contact with the measurement point (1). Therefore, in the conventional scanning probe microscope, the contact between the probe 2a and the sample S cannot be detected in the state where the probe 2a is in contact with the measurement point (5) (FIGS. 9A and 9B). Therefore, the conventional scanning probe microscope presses the sample S with a larger pressing force, and detects the contact between the probe 2a and the sample S when the amount of deflection in the + Z direction to the extent that the cantilever 2 exceeds a certain value is generated. (Fig. 9 (c), (d)). Therefore, the probe 2a may be worn or the sample S may be deformed. The scanning probe microscope 1 of the present embodiment can detect the contact between the probe 2a and the sample S based on the amount of twist of the cantilever 2. That is, in the scanning probe microscope 1, when the probe 2a comes into contact with the measurement point (5) having a slope (FIGS. 9A and 9B), the probe 2a and the sample S are based on the amount of twist of the cantilever 2. Contact with can be detected. Therefore, wear of the probe 2a and deformation of the sample S can be suppressed.

FIG. 10 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (6) of the sample S. FIG. 10A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (6), and FIG. 10B shows the probe 2a at the measurement point (6). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 10 (c) shows a side view of the cantilever 2 as seen from the −Y direction in a state where the probe 2a comes into contact with the measurement point (6) and then is further pushed in, and FIG. 10 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 6) and then pushed further is shown.

As shown in FIGS. 10A and 10B, when the probe 2a comes into contact with the measurement point (6), the cantilever 2 is subjected to a vertical drag corresponding to the pressing force in the axial direction perpendicular to the surface of the sample S. In addition, the amount of deflection in the + Z direction corresponding to the force for tilting the probe 2a and the pressing force is generated. Further, the cantilever 2 is twisted in the −Y direction due to the normal force corresponding to the pressing force. Further, as shown in FIGS. 10 (c) and 10 (d), when the probe 2a is pressed against the measurement point (6) from the state of being in contact with the measurement point (6), the cantilever 2 generates a deflection amount corresponding to the pressing force and the pressing force. The amount of twist in the -Y direction is generated by the normal force corresponding to. Therefore, in the contact determination unit 42, the probe 2a determines whether the deflection amount indicated by the first detection signal exceeds the deflection upper limit threshold value or the twist amount indicated by the second detection signal exceeds the twist upper limit threshold value. It is possible to determine whether or not it has come into contact with the surface of the.

FIG. 11 is a diagram showing the displacement of the cantilever 2 when the probe 2a comes into contact with the measurement point (7) of the sample S. FIG. 11A shows a side view of the cantilever 2 as seen from the −Y direction when the probe 2a is in contact with the measurement point (7), and FIG. 11B shows the probe 2a at the measurement point (7). The side view of the cantilever 2 seen from the −X direction in the contact state is shown. FIG. 11 (c) shows a side view of the cantilever 2 as seen from the −Y direction in a state where the probe 2a comes into contact with the measurement point (7) and then is further pushed in, and FIG. 11 (d) shows the measurement point (d). The side view of the cantilever 2 seen from the −X direction in the state where the probe 2a is brought into contact with 7) and then pushed further is shown.

As shown in FIGS. 11A and 11B, in the primary contact state in which the probe 2a is in contact with the measurement point (7), the cantilever 2 has a normal force corresponding to the pressing force on the surface of the sample S. The amount of deflection in the −Z direction corresponding to the force for tilting the probe 2a and the pressing force is generated in the axial direction perpendicular to. Further, the cantilever 2 is twisted in the −Y direction due to the normal force corresponding to the pressing force. On the other hand, as shown in FIGS. 11 (c) and 11 (d), in the case of a secondary contact state in which the probe 2a is pressed against the measurement point (6) from the state in which the probe 2a is in contact with the measurement point (6), the pressing force of the cantilever 2 is deflected by the normal force. When the force for generating the amount is exceeded, the bending direction changes, and the bending amount is generated in the + Z direction. Further, the cantilever 2 is twisted in the −Y direction due to the normal force corresponding to the pressing force.

In the conventional scanning probe microscope, it is determined that the probe 2a has come into contact with the surface of the sample S only when the amount of deflection in the + Z direction exceeds a certain value. In the contact state (FIGS. 11A and 11B), the contact between the probe 2a and the sample S cannot be determined. Therefore, as described above, in the conventional scanning probe microscope, the sample S is pressed with a larger pressing force, and the cantilever 2 is bent in the + Z direction in the secondary contact state (FIGS. 11 (c) and 11 (d)). Occasionally, the contact between the probe 2a and the sample S will be detected. Therefore, the probe 2a may be worn or the sample S may be deformed. Since the scanning probe microscope 1 of the present embodiment determines that the probe 2a has come into contact with the surface of the sample S when the amount of deflection of the cantilever 2 exceeds the first range, the probe 2a is determined to be in contact with the surface of the sample S. The primary contact state between the sample S and the sample S can be determined. Therefore, wear of the probe 2a and deformation of the sample S can be suppressed.

As described above, in the conventional scanning probe microscope, the pressing force at the time of contact detection for detecting the contact between the probe 2a and the sample S varies depending on the shape of the sample surface with which the probe contacts. In the scanning probe microscope 1 of the present embodiment, the state in which the probe 2a is in contact with the sample S is measured in the lifting direction (−Z direction) and the twisting direction (± Y direction) in addition to the amount of deflection in the lifting direction (+ Z direction). Since even the displacement (twist amount) of the sample S is detected and judged in all directions, the variation in the pressing force due to the influence of the inclination of the surface of the sample S is reduced, and the probe 2a is prevented from being excessively pressed against the sample S. it can.

Returning to FIG. 1, the drive unit 43 controls the drive of the cantilever 2 by the mobile drive unit 5. The drive unit 43 brings the probe 2a into contact with the surface of the sample S by lowering the cantilever 2 by the moving drive unit 5. Then, the measuring unit 44 measures the uneven shape of the surface of the sample S by measuring the distance that the cantilever has moved when the probe 2a and the surface of the sample S come into contact with each other. In this way, the measuring unit 44 determines the relative distance (hereinafter, simply referred to as “relative distance”), which is the distance moved relative to the other when the probe 2a and the surface of the sample S are brought into contact with each other. Measure. In the present embodiment, the relative distance is the moving distance in which the cantilever 2 is lowered until the probe 2a and the surface of the sample S come into contact with each other, but the sample S is raised until the probe 2a and the surface of the sample S come into contact with each other. It may be the distance traveled. The measuring unit 44 may measure the physical characteristics of the surface of the sample S. For example, the measuring unit 44 may measure the uneven shape of the surface of the sample S by continuously scanning the surface of the sample S in a state where the probe 2a and the surface of the sample S are in contact with each other. Further, the driving unit 43 intermittently scans the surface of the sample S by bringing the probe 2a and the surface of the sample S into contact with each other only at the measurement points on the surface of the plurality of sample S set in advance, and the surface of the sample S. It may be measured by an intermittent measuring method for measuring the uneven shape of the sample. In the intermittent measurement method, when the probe 2a moves between a plurality of preset measurement points, the probe 2a is separated from the surface of the sample S by a certain distance (hereinafter, “pulled apart” in order to avoid contact with the convex portion of the sample S. The probe 2a is moved closer to the surface of the sample S at the next measurement point by moving with a distance (referred to as "distance"). Then, the probe 2a is brought into contact with the surface of the sample S to measure the uneven shape of the surface of the sample S, and then the probe 2a is retracted to a position separated by the separation distance again.
In the present embodiment, a case where the control device 7 uses the intermittent measurement method will be described.

The drive unit 43 includes a first drive unit 431 and a second drive unit 432.
When scanning the surface of the sample S, the first drive unit 431 outputs a first drive signal to the Z-direction drive device 22 in order to bring the probe 2a into contact with the surface of the sample S, and lowers the cantilever 2. As a result, the first driving unit 431 brings the probe 2a and the surface of the sample S close to each other.

The first drive unit 431 stops the output of the first drive signal to the Z-direction drive device 22 when at least one of the first contact signal and the second contact signal is output from the contact determination unit 42. As a result, the lowering operation of the cantilever 2 is stopped.

After the lowering operation of the cantilever 2 is stopped by the first driving unit 431, the measuring unit 44 measures the relative distance. When the measurement of the relative distance by the measuring unit 44 is completed, the first driving unit 431 pulls the probe 2a away from the surface of the sample S and retracts it by the distance. Then, the second drive unit 432 outputs the second drive signal to the XY scanner 25 in order to move the probe 2a to the measurement lowering position located immediately above the next measurement position. Then, the first drive unit 431 lowers the cantilever 2 from the measurement lowering position, contacts the probe 2a at the next measurement position, and the measurement unit 44 starts measuring the relative distance again.

The measuring unit 44 measures the uneven shape of the surface of the sample S in a state where the probe 2a and the surface of the sample S are in contact with each other. That is, the measuring unit 44 measures the uneven shape of the surface of the sample S by acquiring the relative distance for each measurement position. For example, the measuring unit 44 may calculate the relative distance based on the voltage value of the first drive signal in a state where the probe 2a and the surface of the sample S are in contact with each other. Further, the measuring unit 44 may directly measure the displacement of the first driving unit 431 by a sensor (not shown), or may directly measure the height of the probe by a sensor (not shown).

The flow of the contact detection process for detecting the contact between the probe 2a and the surface of the sample S in the control device 7 of the present embodiment will be described below. FIG. 12 is a diagram showing a flow of a contact detection process for detecting contact between the probe 2a and the surface of the sample S in the control device 7 of the present embodiment. As an initial condition, it is assumed that the probe 2a is located at the measurement descending position at a predetermined measurement point.

The first drive unit 431 outputs a first drive signal to the Z-direction drive device 22 in order to bring the probe 2a into contact with the surface of the sample S, and lowers the cantilever 2 to bring the probe 2a closer to the surface of the sample S. The approaching operation is started (step S100).

The first determination unit 421 determines whether or not the amount of deflection indicated by the first detection signal output from the light detection unit 33 is out of the first range (step S101). The first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S when the amount of deflection indicated by the first detection signal output from the light detection unit 33 is out of the first range, and the first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S. The contact signal is output to the first drive unit 431. The second determination unit 422 outputs a second detection signal from the light detection unit 33 when it is determined that the amount of deflection indicated by the first detection signal output from the light detection unit 33 is within the first range. It is determined whether or not the amount of twist indicated by is out of the second range (step S102). The second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S when the amount of twist indicated by the second detection signal output from the light detection unit 33 is out of the second range, and the second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S. The contact signal is output to the first drive unit 431. The second determination unit 422 continues the approaching operation of the cantilever when the twist amount indicated by the second detection signal output from the light detection unit 33 is not outside the second range. In FIG. 12, the process of step S102 is executed after the process of step S101, but the present invention is not limited to this. The control device 7 in the present embodiment may perform the process of step S101 after the process of step S102, or may execute the process of step S101 and the process of step S102 in parallel.

When the first drive unit 431 acquires at least one of the first contact signal and the second contact signal, the first drive unit 431 stops the output of the first drive signal to the Z-direction drive device 22 to cause the cantilever 2 to operate. The approaching operation is stopped (step S103).

The measuring unit 44 measures the uneven shape of the surface of the sample S by calculating the relative distance based on the voltage value of the first drive signal in a state where the probe 2a and the surface of the sample S are in contact with each other (the uneven shape of the surface of the sample S is calculated. Step S104).

When the measurement of the uneven shape at a predetermined measurement position by the measurement unit 44 is completed, the first drive unit 431 pulls the probe 2a away from the surface of the sample S and retracts it by a distance (step S105). Then, the second drive unit 432 outputs the second drive signal to the XY scanner 25 to move the probe 2a to the measurement lowering position located immediately above the next measurement position (step S106).

In the contact detection process, the scanning probe microscope 1 may perform not only the time-series measurement as described above but also parallel measurement (hereinafter, referred to as “parallel measurement”). For example, the measuring unit 44 measures the relative distance when at least one of the first contact signal and the second contact signal is output from the contact determination unit 42, and at the same time, the first driving unit 431 is in the Z direction. By inverting the output of the first drive signal to the drive device 22, the lowering operation of the cantilever 2 is reversed. Hereinafter, the parallel measurement in the present embodiment will be described. FIG. 13 is a diagram showing a flow of parallel measurement of the contact detection process in the present embodiment.

The first drive unit 431 outputs a first drive signal to the Z-direction drive device 22 in order to bring the probe 2a into contact with the surface of the sample S, and lowers the cantilever 2 to bring the probe 2a closer to the surface of the sample S. The approaching operation is started (step S200).

The first determination unit 421 determines whether or not the amount of deflection indicated by the first detection signal output from the light detection unit 33 is out of the first range (step S201). The first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S when the amount of deflection indicated by the first detection signal output from the light detection unit 33 is out of the first range, and the first determination unit 421 determines that the probe 2a has come into contact with the surface of the sample S. The contact signal is output to the first drive unit 431. The second determination unit 422 outputs a second detection signal from the light detection unit 33 when it is determined that the amount of deflection indicated by the first detection signal output from the light detection unit 33 is within the first range. It is determined whether or not the amount of twist indicated by is out of the second range (step S202). The second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S when the amount of twist indicated by the second detection signal output from the light detection unit 33 is out of the second range, and the second determination unit 422 determines that the probe 2a has come into contact with the surface of the sample S. The contact signal is output to the first drive unit 431.

For example, the measuring unit 44 continuously measures the relative distance when the contact detection process is started. Then, the measuring unit 44 sets the relative distance when at least one of the first contact signal and the second contact signal is output from the contact determination unit 42, and the relative distance when the probe 2a comes into contact with the sample S. The distance is determined (step S203). The measuring unit 44 may measure the relative distance only when the first contact signal and the second contact signal are output from the contact determination unit 42.
At the same time that the relative distance is determined by the measuring unit 44, the first driving unit 431 pulls the probe 2a away from the surface of the sample S and retracts it by the distance (step S203). Then, the second drive unit 432 outputs the second drive signal to the XY scanner 25 to move the probe 2a to the measurement lowering position located immediately above the next measurement position (step S204).

As described above, in the parallel measurement in the present embodiment, the relative distance when the probe 2a of the cantilever comes into contact with the sample S can be measured without stopping the cantilever 2. When the relative distance is measured after the cantilever 2 is stopped, an overrun occurs for a short time until the cantilever 2 is stopped, the error of the measured value of the measuring unit 44 increases, and the force on the sample S increases. It may be pushed hard by the amount of error.
Since the scanning probe microscope 1 of the present embodiment can simultaneously detect the contact between the probe 2a and the sample S and measure the relative distance at the time of the contact, the overrun of the cantilever 2 is suppressed and the measurement is performed. It is possible to suppress an increase in the error of the measured value of the unit 44. Therefore, the scanning probe microscope 1 can reduce the strong pressing of the force on the sample S.

As described above, the scanning probe microscope 1 in the present embodiment is a scanning probe microscope in which the probe 2a is brought into contact with the surface of the sample S and the surface of the sample S is scanned by the probe 2a, and the deflection of the cantilever 2 is obtained. It is determined whether or not the probe 2a has come into contact with the surface of the sample S based on the amount and the amount of twist. Specifically, the scanning probe microscope 1 has at least one of a first condition in which the amount of deflection of the cantilever 2 exceeds the first range and a second condition in which the amount of twist of the cantilever 2 exceeds the second range. When it is established, it is determined that the probe 2a has come into contact with the surface of the sample S. As a result, when the surface of the sample S with which the probe 2a comes into contact is a slope, the value of the contact detection pressing force for detecting the contact between the probe 2a and the surface of the sample S changes as compared with the horizontal plane. Can be improved.

Further, in the above-described embodiment, the scanning probe microscope 1 determines whether or not the surface of the sample S in the scanning direction is inclined based on the amount of twist indicated by the second detection signal output by the photodetector 33. You may judge. Further, the scanning probe microscope 1 predicts the magnitude (angle) of the surface inclination of the sample S in the scanning direction based on the magnitude of the twist amount indicated by the second detection signal output by the photodetector 33. You may. Further, the scanning probe microscope 1 determines whether the inclination of the surface of the sample S in the scanning direction is a downward inclination or an upward inclination based on the code of the amount of twist indicated by the second detection signal output by the photodetector 33. You may.

Further, in the above-described embodiment, the scanning probe microscope 1 calculates the separation distance for retracting the probe 2a in the direction away from the sample S based on the amount of twist indicated by the second detection signal output by the photodetector 33. A calculation unit may be further provided. That is, in the intermittent measurement method, the scanning probe microscope 1 may determine the pulling distance when moving to the next measurement lowering position based on the twist amount of the cantilever 2. For example, the calculation unit determines the separation distance based on the magnitude and sign of the twist amount indicated by the second detection signal output by the light detection unit 33. Further, the calculation unit includes a table in which the twist amount and the separation distance are associated with each other, and by selecting the separation distance corresponding to the twist amount indicated by the second detection signal output by the photodetection unit 33 from the above table. , The separation distance may be determined. The optimum value of the pulling distance depends on the shape of the surface of the sample S. Therefore, when scanning an unknown sample whose surface shape is unknown, it is necessary to estimate the optimum separation distance in advance. In the present embodiment, the pulling distance can be determined according to the inclination of the slope of the sample S in the scanning direction. Therefore, when the probe 2a is moved to the measurement descending position located directly above the next measurement position, the probe 2a It is possible to reduce the contact between the sample S and the sample S and shorten the measurement time.

Further, in the above-described embodiment, the scanning probe microscope 1 is indicated by a second detection signal output by the photodetector 33 when the probe 2a is moved to a measurement descending position located immediately above the next measurement position. The contact between the probe 2a and the surface of the sample S may be detected based on the amount of twist. For example, when the scanning probe microscope 1 detects contact between the probe 2a and the surface of the sample S when the probe 2a is moved to the measurement descending position located immediately above the next measurement position, the movement is performed. The probe 2a is stopped and retracted from the surface of the sample S in the + Z direction. As a result, when the probe 2a is moved to the measurement lowering position, even if the probe 2a and the sample S come into contact with each other, it is possible to suppress the wear of the probe 2a and the damage of the sample S as compared with the conventional case.

Further, in the above-described embodiment, the scanning probe microscope 1 has the probe 2a and the probe 2a based on the amount of deflection indicated by the first detection signal and the amount of twist indicated by the second detection signal in the retracting operation in the intermittent measurement method. It may be determined that the surface of the sample S is not in contact with the surface.

Further, in the above-described embodiment, when the scanning probe microscope 1 continuously scans the surface of the sample S in a state where the probe 2a and the surface of the sample S are in contact with each other, the amount of deflection indicated by the first detection signal is large. The Z-direction drive device 22 may be controlled so that it is within the first range and the amount of twist indicated by the second detection signal is within the second range. As a result, even when the surface of the sample S has a slope, the distance between the probe 2a and the surface of the sample S can be maintained at a constant distance.

Further, in the above-described embodiment, the probe 2a and the sample S may be moved relative to the XY direction by moving the cantilever 2 instead of moving the sample table 4.

The control device 7 in the above-described embodiment may be realized by a computer. In that case, the program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. In that case, a program may be held for a certain period of time, such as a volatile memory inside a computer system serving as a server or a client. Further, the above program may be for realizing a part of the above-mentioned functions, and may be further realized for realizing the above-mentioned functions in combination with a program already recorded in the computer system. It may be realized by using a programmable logic device such as FPGA (Field Programmable Gate Array).

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention.

The execution order of each process such as operation, procedure, step, and step in the device, system, program, and method shown in the claims, the specification, and the drawing is particularly "before" and "prior to". It should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Even if the scope of claims, the specification, and the operation flow in the drawings are explained using "first", "next", etc. for convenience, it means that it is essential to carry out in this order. It's not a thing.

1 Scanning probe microscope 2 Cantilever 5 Moving drive unit 6 Displacement detection unit 7 Control device 42 Contact judgment unit 43 Drive unit 44 Measurement unit 421 1st judgment unit 422 2nd judgment unit

Claims (9)

A scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe.
A cantilever equipped with the probe at the tip,
A displacement detection unit that detects the amount of deflection and the amount of twist of the cantilever,
A contact determination unit that determines the primary contact of the probe with the sample surface based on the amount of deflection and the amount of twist in the cantilever detected by the displacement detection unit.
A scanning probe microscope equipped with. A scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe.
A cantilever equipped with the probe at the tip,
A displacement detection unit that detects the amount of deflection and the amount of twist of the cantilever,
A contact determination unit capable of determining the primary contact of the probe with the sample surface using the value of the amount of deflection in the −Z direction of the cantilever detected by the displacement detection unit.
A scanning probe microscope equipped with. The first or second aspect of the present invention, wherein the contact determination unit determines that the probe has come into contact with the sample surface when at least one of the deflection amount and the twist amount exceeds a predetermined range. Scanning probe microscope. Any of claims 1 to 3, further comprising a measuring unit that measures a relative distance, which is a distance that one of the probes is relatively moved relative to the other when the probe and the surface of the sample are brought into contact with each other. The scanning probe microscope according to one item. The scanning probe according to claim 4, further comprising a moving drive unit that retracts the probe in a direction away from the sample and moves to the next measurement position of the sample after the relative distance is measured by the measuring unit. microscope. The scanning probe microscope according to claim 5, further comprising a calculation unit for a retracting distance of the probe in a direction away from the sample based on the amount of deflection and the amount of twist. The movement driving unit moves to a measurement lowering position located directly above the next measurement position that does not come into contact with the probe after the evacuation, and lowers the probe from the measurement lowering position to the measurement position. The scanning probe microscope according to claim 6. Claim 3 or claim 3, further comprising a moving drive unit that scans with the probe so that the amount of deflection detected by the displacement detection unit is within the first range and the amount of twist is within the second range. 4. The scanning probe microscope according to 4. This is a probe contact detection method of a scanning probe microscope in which a probe is brought into contact with the sample surface and the sample surface is scanned by the probe.
A displacement detection step for detecting the amount of deflection and the amount of twist of the cantilever provided with the probe at the tip,
A contact determination step for determining the primary contact of the probe with the sample surface based on the amount of deflection and the amount of twist in the cantilever detected by the displacement detection step.
A method for detecting probe contact with a scanning probe microscope.

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