JPH08233836A - Scanning probe microscope, standard for height direction calibration, and calibration method - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Providing a highly practical scanning probe microscope, calibration method, and calibration standard instrument that has a simple structure, is inexpensive, and can perform highly accurate calibration easily. To do. [Structure] Sample table 12 on which sample 14 is placed, and probe 22
Equipped with a cantilever 21, xyz scanner 20 that attaches the cantilever and displaces the relative position of the probe and sample,
Displacement detector 23 that detects the displacement of the cantilever, xyz
Equipped with a strain gauge 61X-61Z that detects the movement amount of the scanner,
While scanning the sample surface with the xyz scanner, the deflection amount of the cantilever based on the physical quantity acting between the probe and the sample is detected by the displacement detector, the deflection amount is controlled, and the sample surface is measured. A calibration measurement reference sample 51 having a grid pattern 53 in which a precision pitch p1 is determined, and the reference sample 51 is arranged so as to be inclined on a sample table so that one direction in which the pitch is determined matches the inclination direction. An inclined block 54 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning probe microscope suitable for measuring and analyzing the surface shape and surface physical properties of semiconductor devices, optical disks, etc., as well as a standard for height direction calibration and a calibration method.

[0002]

2. Description of the Related Art A scanning probe (probe) microscope has a measurement resolution of an atomic order and is used in various fields such as surface shape measurement. The scanning probe microscope includes a scanning tunneling microscope (STM), an atomic force microscope (AFM), a magnetic force microscope (MFM), etc., depending on the physical quantity to be detected. Among them, the atomic force microscope is suitable for detecting the shape of the sample surface with high resolution.
It is used to measure the surface shape of optical disks and magnetic disks.

An example of a conventional scanning probe microscope will be described with reference to FIG. The illustrated device shows an AFM, which is one of the scanning probe microscopes. This AFM is an AFM combined with an optical microscope. The XY stage 12 is arranged on the base 11, and the sample 14 to be measured is placed on the sample table 13 on the XY stage 12. X
The Y stage 12 has a function of arbitrarily moving the sample table 13 within an XY plane defined by the orthogonal X-axis direction and Y-axis direction. The XY plane is a plane that is horizontal in FIG. 4 and is perpendicular to the paper surface. Sample table 13
The sample 14 placed thereon is moved in an arbitrary direction within the XY plane as the sample table 13 moves. A mounting frame body 15 is provided on the base 11, and an optical microscope 16 and a Z coarse movement stage 17 are mounted on the mounting frame body 15. The objective lens 18 of the optical microscope 16 faces downward and faces the sample 14. The Z coarse movement stage 17 is a moving mechanism that enables coarse movement in the Z-axis direction perpendicular to the XY plane. Below the Z coarse movement stage 17, x
The yz scanner 20 is attached. xyz scanner 2
A cantilever 21 is attached to the lower surface of 0. xyz
The scanner 20 has three cantilevers 21 which are orthogonal to each other.
It has a function of finely moving in the directions of the axes X, Y, and Z. A probe 22 facing the surface of the sample 14 is provided at the tip of the cantilever 21. A displacement detector 23 attached to the attachment frame 15 is arranged above the cantilever 21. The displacement detector 23 is a device for detecting the displacement of the probe 22 at the tip of the cantilever 21, and the displacement detector 23 uses, for example, a detection optical system including a laser light source and a photodetector.

The Z coarse movement stage 17, the xyz scanner 20, the cantilever 21, the probe 22, and the displacement detector 23 form a mechanical portion 24 of the AFM.
During the measurement operation, the cantilever 21 and the probe 22 are moved in the Z axis direction by the Z coarse movement stage 17 and finely moved in the three axis directions by the xyz scanner 20.

The operation of the XY stage 12 is performed under the control of the XY stage control circuit 25.
The movement amount of is detected by the stage displacement meter 26. The XY stage control circuit 25 receives data regarding the control amount from the computer 27, and the stage displacement meter 26 sends data regarding the detected movement amount to the computer 27. The operation of the Z coarse movement stage 17 is controlled by the Z coarse movement stage control circuit 28,
The operation of the xyz scanner 20 is performed by the xyz scanner control circuit 2
Controlled by 9. In the position control of the probe 22 in the Z-axis direction based on the Z coarse movement stage control circuit 28 and the xyz scanner control circuit 29, the atomic force acting between the probe 22 and the surface of the sample 14 is kept constant. As described above, it is performed to adjust the distance between the two. Therefore, the displacement detection data detected by the displacement detector 23 is taken out and the displacement detection data and the force set value related to the atomic force are set by the force setter 30. And the control data such that the interatomic force acting between the probe and the sample surface always agrees with the force set value is sent from the force setter 30 to the Z coarse movement stage control circuit 28 and the xyz scanner control circuit 29. Given. The calculator 27 is the force setting device 3
The force setting value is given to 0, and the Z coarse movement stage control circuit 28 and the xyz scanner control circuit 29 are connected to exchange data with these circuits. The computer 27 is equipped with a monitor 31, and the image of the sample surface obtained by the measurement is displayed on this monitor 31.

The operation and operation of the AFM having the above structure is as follows. The sample 14 is placed on the sample table 13 on the XY stage 12, and the optical microscope 1 is used while moving the sample 14 in the XY plane using the XY stage 12.
6 is used to find the observation position of the sample 14. Next, the probe 22 of the cantilever 21 is aligned with that position. Probe 2
When the second position is aligned with the observation position of the sample 14, the XY stage 12 is also used to move the sample 14 by a distance d1 shown in FIG. The probe 22 aligned with the observation position of the sample 14 is brought close to the surface of the sample 14 by the Z coarse movement stage 17 up to the position where the atomic force acts. Next, while using the Z-direction driving unit of the xyz scanner 20 to control so that the force received by the probe 22 of the cantilever 21 from the sample surface becomes constant, at the same time, using the XY-direction driving unit of the xyz scanner 20. The probe 22 is scanned. The computer 27 calculates the sample 14 based on the control drive signal provided to the xyz scanner 20 at this time.
An image of the observation surface of is created and displayed on the monitor 31. In this way, an atomic level image of the observation surface of the sample 14 can be observed.

According to the AFM having the above structure, for example, the range of 88 × 66 μm in the 100 × optical microscope 16 is 0.25 μm in the horizontal direction and 0.5 μm in the vertical direction.
In addition, the AFM 24 can measure a range of about 10 × 10 μm with a resolution of 0.1 nm in the horizontal direction and 0.01 nm in the vertical direction.

Next, a specific example of the xyz scanner 20 will be described with reference to FIGS. The xyz scanner shown in FIG. 5 is a tube type scanner 32 in which the cantilever 21 is attached to the edge of the lower end. The tube-type scanner 32 has an X-shaped structure on the outer surface of the piezoelectric cylinder 33 that is deformed by voltage application.
X-electrode 34 that causes displacement in each direction of the axis, Y-axis, and Z-axis
The y electrode 35 and the z electrode 36 are provided, and a common ground electrode is provided on the inner surface of the piezoelectric cylinder 33. The piezoelectric cylinder 33 is formed of a piezoelectric element. The x-axis electrode 34 in the X-axis direction and the y-electrode 35 in the Y-axis direction each consist of two electrodes, and the two x-electrodes 34 forming a set are arranged at positions on the opposite sides of the surface of the piezoelectric cylinder 33. The two y-electrodes 35, which are also arranged on the surface of the piezoelectric cylindrical body 33, are also arranged at opposite positions. x electrode 34
The y-electrodes 35 and the y-electrodes 35 are arranged around the circumference of the piezoelectric cylinder 33 at 90-degree angles. In FIG. 5, for example, when a positive voltage is applied to the left x electrode 34 and a negative voltage is applied to the right x electrode 34, X is proportional to the applied voltage.
Displacement occurs on the positive side on the axis. Further, when the voltage application is reversed in the two x electrodes 34, the displacement occurs in the negative direction opposite to the X axis. The operation in the Y-axis direction is similarly performed by the y-electrode 35.

The problem of the xyz scanner 20 will be described. For example, the probe 2 in the tube-type scanner 32
2, the upper end, that is, the upper end of the piezoelectric cylinder 33 is attached to the Z coarse movement stage 17 as described with reference to FIG. Therefore, a geometrical movement error occurs in the X-axis direction and the Y-axis direction. Furthermore, when the piezoelectric cylinder 33 of the tube scanner 32 is deformed by applying a voltage in each of the X, Y, and Z axis directions, hysteresis and a creep phenomenon occur, and scanning is performed with good reproducibility in proportion to the applied voltage. I can't. Xyz as above
In the scanner 20, the measurement image is distorted due to movement error, hysteresis, and creep phenomenon, and accurate measurement cannot be performed.

Therefore, in order to solve the above problem and enable accurate measurement, there is an example in which a configuration as shown in FIG. 6 is conventionally added. That is, the tube scanner 32 is provided with a lever 37, and the lever 37
Are provided with external displacement sensors 38X, 38Y, 38Z that detect displacements in the X, Y, Z axial directions. As the external displacement sensor, for example, a capacitance displacement meter (resolution of 1 nm) or the like is used. When the tube-type scanner 32 is operated, its displacement amount is detected by the external displacement sensors 38X, 38Y, 38Z, and this detection signal is fed back to a controller (not shown) that controls the operation of the scanner 32, and such feedback control is performed. Based on the above, the scanner 32 is caused to perform a desired scanning movement.

Another example of the conventional configuration is shown in FIG. This configuration corresponds to the X of the tube type scanner 32.
A configuration is shown in which a strain gauge 39 for detecting the amount of movement is attached to the portion of the piezoelectric element involved in the displacement in each direction of the axis, the Y axis, and the Z axis. In this configuration example, calibration is performed before actual measurement, and when displacement calibration of the scanner 32 is performed, the external displacement sensor shown in FIG. 6 is combined and each electrode 34, 35, 36 is connected. The scanner 32 is operated by applying a required voltage, and each strain gauge 39 at that time is operated.
Then, the relationship between the output signal of 1 and the detection signal of the external displacement sensor is obtained. The relationship between the output signal of the strain gauge 39 and the detection signal of the external displacement sensor is the relationship of the amount of strain of the piezoelectric element in each axial direction corresponding to the actual amount of displacement. Scanner 3 using AFM
2 is operated to perform an actual measurement, the scanning operation is performed using the calibration value obtained by the strain gauge 39. This makes it possible to obtain an accurate measurement image.

Further, as an apparatus configured to perform calibration, there is an apparatus disclosed on pages 879 to 880 of "Proceedings of the 1993 Precision Engineering Society Spring Conference Academic Lectures" (Reference 1). In this device, a mirror is provided on the inner surface of one end surface of a cylindrical piezoelectric body, and light is emitted to the mirror through the inside of the cylindrical piezoelectric body to accurately detect the displacement amount of the cylindrical piezoelectric body. Is attached. This makes it possible to correct the distortion of the AFM image due to the cylindrical piezoelectric body.

[0013]

The tube type scanner 3
The conventional configuration for solving the above problem No. 2 has the following problems. According to the configuration provided with the external displacement sensor shown in FIG. 6, the number of components increases, the cost increases, and it is not practical. The configuration shown in FIG. 7 has a problem in that calibration must be performed from time to time, and an expensive external displacement sensor is required in the calibration from time to time, which is also impractical. Further, the device disclosed in Document 1 also requires an expensive optical displacement sensor, which is problematic in terms of practicality. Further, according to the configuration using the external displacement sensor or the optical displacement sensor, there is a problem that the calibration value is changed or becomes inaccurate due to a change in a mounting state of the displacement sensor.

An object of the present invention is to solve the above problems, a scanning probe microscope having a simple structure, a low cost, and a highly practical calibration that can be easily performed, a calibration method therefor, and a calibration method therefor. To provide a reference device.

[0015]

A method of calibrating a scanning probe microscope according to a first aspect of the present invention includes a sample table on which a sample is placed, a cantilever having a probe facing the sample, and a cantilever attached. The three-axis fine movement mechanism includes a three-axis fine movement mechanism that displaces the relative position of the probe and the sample, a displacement detection device that detects the displacement of the cantilever, and a movement amount sensor that detects the movement amount of the three-axis fine movement mechanism. Applied to a scanning probe microscope that measures the surface of the sample by detecting the deflection of the cantilever based on the physical quantity acting between the probe and the sample while scanning the surface of the sample with a displacement detector and controlling the deflection. This is a calibration method that is performed by arranging a reference sample on a sample table, operating the 3-axis fine movement mechanism to measure the surface of the reference sample, and measuring the movement amount of the 3-axis fine movement mechanism during the measurement. It detected as a calibration value capacitors, a method of performing an actual sample measurement using a calibration value obtained by the operation amount sensor.

A second aspect of the present invention is characterized in that, in the first aspect, the reference sample has a grid pattern in which a highly precise pitch is defined in at least one direction.

According to a third aspect of the present invention, in the second aspect, the reference sample is arranged at a known angle on the sample table so that one direction in which the pitch is determined coincides with the tilt direction.
It is characterized in that the sine value of the pitch is used to obtain a calibration value in the height direction.

A fourth aspect of the present invention is characterized in that, in the third aspect, the sine value of the pitch is a value having a nano-order accuracy.

A calibration standard for a scanning probe microscope according to a fifth aspect of the present invention is a sample table on which a sample is placed, a cantilever having a probe facing the sample, a cantilever attached and the probe and the sample. Is provided with a three-axis fine movement mechanism for displacing the relative position of the sample, a displacement detection device for detecting the displacement of the cantilever, and a movement amount sensor for detecting the movement amount of the three-axis fine movement mechanism. It is used in a scanning probe microscope that detects a deflection amount of a cantilever based on a physical amount acting between a probe and a sample while scanning with a displacement detection device and controls the deflection amount to measure the surface of a sample. The sample pattern has a grid pattern with a highly precise pitch, and is tilted at a known angle on the sample table so that one direction with the pitch matches the tilt direction. Is constructed by using a reference sample to be placed in and used as a reference distance sine value of the pitch is determined calibration values in the height direction.

According to a sixth aspect of the present invention, in the fifth aspect, an inclined block having an inclined surface of a known angle is prepared on a sample table, and a reference sample is inclined so that one direction and the inclined direction of the inclined block coincide with each other. It is characterized in that it is arranged on the inclined surface of the block.

A seventh aspect of the present invention is characterized in that, in the fifth or sixth aspect, the sine value of the pitch is a value having a nano-order accuracy.

A scanning probe microscope according to an eighth aspect of the present invention is a sample table on which a sample is placed, a cantilever having a probe facing the sample, a cantilever attached, and a relative position between the probe and the sample. A three-axis fine movement mechanism for displacement, a displacement detection device for detecting displacement of the cantilever, and
With an operation amount sensor that detects the operation amount of the shaft fine movement mechanism,
Measuring the surface of the sample by detecting the deflection of the cantilever based on the physical quantity acting between the probe and the sample by the displacement detector while scanning the surface of the sample by the three-axis fine movement mechanism and controlling the deflection. And a reference sample for calibration measurement having a grid pattern in which a highly precise pitch is defined in at least one direction, and this reference sample are placed on a sample table so that the one direction in which the pitch is defined matches the tilt direction. It is configured to include an arrangement means for arranging at an angle.

A ninth aspect of the present invention is characterized in that, in the eighth aspect, the arrangement means is an inclined block having an inclined surface whose inclination angle is known.

[0024]

In the present invention, a planar reference sample having a grid pattern having a known fine pitch is used,
In particular, by arranging this at a known angle and using it as a reference sample, it becomes possible to use it as a reference sample that can be calibrated in the height direction. For height calibration,
The sine value of the fine pitch based on the known angle is used as the reference distance, and the reference distance on the order of nanometers can be obtained by appropriately setting the inclination angle. In this way, the standard for height calibration can be easily prepared in the scanning probe microscope.

[0025]

Embodiments of the present invention will be described below with reference to FIGS. FIGS. 1 and 2 show an example of a calibration standard used in the method for calibrating a scanning probe microscope according to the present invention, and FIG. 3 shows a method of using the calibration standard and an apparatus configuration required for the method. . In FIG. 3, elements that are substantially the same as the elements described in FIG. 4 above are given the same reference numerals.

The reference sample 51 used as the calibration reference device shown in FIG. 1 is a calibration that is performed before the actual sample measurement, if necessary, when the installation position of the device is changed or the measurement conditions are changed. It is used as a sample in measurement. The reference sample 51 is a flat two-dimensional (XY) substrate 52.
A lattice pattern 53 in the X-axis direction is formed on the surface 52a. The illustrated lattice pattern 53 is an example, and the ridge portion 5 having a triangular cross-sectional shape and extending in the Y-axis direction.
A plurality of 3a are arranged in the X-axis direction at a pitch (p1) of 0.2 μm, for example. Reference sample 5
The grid pattern 53 of No. 1 is formed by using, for example, a semiconductor manufacturing technique, and is preferably formed by placing an etching mask on the surface of a silicon substrate and applying isotropic etching. Therefore, the pitch p1 of the grid pattern 53 is 0.
The dimension of 2 μm is extremely accurate.

In the reference sample 51, the grid pattern 53 is formed by a plurality of convex ridges having a triangular cross section, but the cross section may have a quadrangular or other shape, and the convex ridges may be used instead of the concave ridges. It may be a strip. As a preferred specific reference sample, for example, the minimum reference sample described in the article on page 8 of the Nikkan Kogyo Shimbun dated February 25, 1994 can be mentioned.

On the sample table, the reference sample 51 is parallel to the sample table, and the direction in which the ridges 53a of the lattice pattern 53 are arranged (the X-axis direction in FIG. 1 or the direction in which the pitch p1 is determined). When the grid pattern 53 is arranged so as to match the X-axis direction defined by, and the grid pattern 53 is measured by AFM, an accurate length p1 that can be used as a scale in the X-axis direction in the grid pattern 53 can be obtained. By using this length p1 as the reference distance, it is possible to obtain the calibration value of the piezoelectric drive unit involved in the movement of the xyz scanner 20 in the X-axis direction. In addition, the reference sample 51 is parallel to the sample table and the grid pattern 5 is formed.
3 is arranged so as to match the arrangement direction of the convex streak portions 53a and the Y-axis direction defined on the sample table, and the lattice pattern 53 is measured by AFM, the movement of the xyz scanner in the Y-axis direction is similarly performed. The calibration value of the piezoelectric drive involved can be obtained.

When performing calibration in the Z-axis direction (height direction) using the calibration reference sample 51 of FIG. 1, preferably, for example, an inclination angle θ (which can be arbitrarily set as shown in FIG.
Inclined block 54 having (as known) inclined surface 54a
Is separately prepared and the reference sample 51 is arranged on the inclined surface of the inclined block 54 to be used as a reference device for obtaining a calibration value in the height direction (Z-axis direction). When the reference sample 51 is arranged so as to be inclined as described above, for example, when the inclination angle θ is 30 degrees, the plurality of ridge portions 5 described above are provided.
3a makes it possible to form steps having a pitch p2 of 0.1 μm in the Z-axis direction. That is, the ridge 53a
The pitch p2 formed by is generally p1 · sin θ
Since it is given as (the sine value of the pitch p1), the smaller the θ, the smaller the pitch p2 in the Z-axis direction can be obtained as the scale (reference distance) for performing the calibration. As described above, the above-described reference sample 51 having the lattice pattern 53 is used, and, for example, the tilt block 54 is prepared, and the reference sample 54 is tilted so that the tilt direction matches the direction in which the pitch p1 is defined. By arranging it, it is possible to make a calibration standard having a resolution of, for example, nano-order in the Z-axis direction, that is, in the height direction.
The Z-axis calibration standard can be made by simply tilting the reference sample 51 by a known angle, and tilting block 54
Is not necessary.

The Z-axis direction reference device realized by inclining the reference sample 51 has a very high accuracy in the height direction, and for example, there is an error of 1 degree in the inclination block 54 where θ is 30 degrees. Even if it does, it has the advantage of changing only about 3 nm.

FIG. 3 shows an AFM with an optical microscope in which the above calibration standard is used. About this AFM, 11
Is a base, 12 is an XY stage, 13 is a sample table, 15 is a mounting frame, 16 is an optical microscope, 17 is a Z coarse movement stage, 20 is an xyz scanner, 21 is a cantilever, 22 is a probe, 23 Is a cantilever displacement detector, and 24 is an AFM. The mounting structure, configuration, and function of each of the above components are as described with reference to FIG.

In the control circuit, an XY stage control circuit 25 and a stage displacement gauge 26 are provided for the XY stage 12, and a Z coarse movement stage 17 is provided with a Z stage.
A coarse movement stage control circuit 28 is provided, and an xyz scanner control circuit 29 is provided for the xyz scanner 20. The Z coarse movement stage control circuit 28 and the xyz scanner control circuit 29 receive control data from the force setting device 30 so that the atomic force acting between the probe and the sample surface always matches the force setting value. Given. The above circuits 25, 28,
A computer 27 including a monitor 31 is provided for the 29, the force setting device 30, and the like. The mounting structure, configuration, and function of each of the above components are as described with reference to FIG.

The following new configuration is added to the above device configuration. The amount of movement of each piezoelectric drive unit (the amount of displacement associated with the movement) in the piezoelectric drive unit in each of the X-axis, Y-axis, and Z-axis of the xyz scanner 20 that is a triaxial (X, Y, Z) fine movement mechanism
Strain gauges 61X, 61Y, 61Z for detecting
A signal related to the operation amount output from each strain gauge is input to the strain gauge detector 62, and the operation amount of the xyz scanner 20 is transmitted through the strain gauges 61X to 61Z.
It is configured to detect at 2. In the calibration measurement using the above-described calibration standard, the scanner calibrator 63 obtains a calibration value based on the signal in each axial direction detected by the strain gauge detector 62. The calibration value obtained by the scanner calibrator 63 is sent to the computer 27 and stored in its storage unit.
Used as a calibration value in actual sample measurement.

In the apparatus configuration shown in FIG. 3, the calibration measurement is performed as follows using the reference device 51. Before the actual sample measurement is performed, the reference sample 51 is placed on the sample stage 13 with the tilt block 54 tilted. The observation area of the reference sample 51 is determined by the optical microscope 16, and the AFM 24 measures the lattice pattern 53 formed on the surface of the reference sample 51. At this time, particularly in the Z-axis direction (height direction), the pitch p2 can be used as a known reference distance as a step between the ridges 53a. Therefore, the piezoelectric drive that takes charge of the operation of the xyz scanner 20 in the Z-axis direction. The calibration value can be obtained based on the actual operation amount of the xyz scanner 20 in the Z-axis direction in relation to the control data of the unit (usually, the driving applied voltage). The actual operation amount in the Z-axis direction of the xyz scanner 20 is obtained through the strain gauge 61Z and the strain gauge detector 62, and the scanner calibrator 63 obtains a calibration value. The calibration value is obtained in the form of a correspondence relationship between the applied voltage of the Z axis direction piezoelectric drive unit in the xyz scanner 20 and the actual operation amount (displacement amount). In the actual measurement, the operation amount of the Z-axis direction piezoelectric drive unit in the xyz scanner 20 is controlled based on the obtained correspondence relationship to enable highly accurate length measurement.

In the above-mentioned embodiment, the calibration in the Z-axis direction is described in particular. However, even when the reference sample 51 is installed horizontally or inclined, the reference in the X-axis direction and the Y-axis direction is set. When the distance is clear, the calibration can be similarly performed in each of the X-axis and Y-axis directions.

In the above-mentioned embodiment, the optical microscope A
Although the FM has been described, the configuration according to the present invention can be similarly applied to other scanning probe microscopes.

[0037]

As is apparent from the above description, according to the present invention, a scanning probe microscope such as an AFM for measuring a fine three-dimensional shape of a sample surface is calibrated as necessary before actual sample measurement. In this calibration measurement, a planar reference sample having a grid pattern with a fine pitch that is already known is used, and this is used as a reference sample by arranging it at a known angle. As a result, since the sample is used as a reference sample that can be calibrated in the height direction, highly accurate calibration in the height direction can be performed with a simple configuration. In this calibration in the height direction, the sine value of the fine pitch is used as the reference distance based on the known angle, and the reference distance on the order of nanometers can be obtained by appropriately setting the inclination angle. In this way, it is possible to realize a calibration standard in the height direction in a scanning probe microscope simply, inexpensively, and highly practical.

[Brief description of drawings]

FIG. 1 is an external perspective view of a reference sample used in a calibration reference device of a scanning probe microscope according to the present invention.

FIG. 2 is a side view when the reference sample of FIG. 1 is installed while being inclined.

FIG. 3 is a diagram showing an embodiment of a scanning probe microscope according to the present invention.

FIG. 4 is a diagram showing an example of a conventional scanning probe microscope.

FIG. 5 is a front view showing an example of a conventional tube scanner.

FIG. 6 is a front view showing a modified example of a conventional tube scanner.

FIG. 7 is a front view showing another modification of the conventional tube scanner.

[Explanation of symbols]

 12 XY stage 13 Sample table 14 Sample 15 Mounting frame 16 Optical microscope 17 Z Coarse stage 20 xyz scanner 21 Cantilever 22 Probe 23 Displacement detector 51 Reference sample 52 Substrate 53 Lattice pattern 53a Convex ridge 54 Inclined block

Claims (9)

[Claims] 1. A sample table on which a sample is placed, a cantilever having a probe facing the sample, a triaxial fine movement mechanism for mounting the cantilever and displacing the relative position of the probe and the sample. A displacement detection device for detecting the displacement of the cantilever and an operation amount sensor for detecting the operation amount of the triaxial fine movement mechanism, and the probe and the probe while scanning the surface of the sample by the triaxial fine movement mechanism. A calibration method applied to a scanning probe microscope that detects a deflection amount of the cantilever based on a physical quantity acting between samples by the displacement detection device, and controls the deflection amount to measure the surface of the sample. A reference sample is placed on the sample table, the three-axis fine movement mechanism is operated to measure the surface of the reference sample, and the operation amount of the three-axis fine movement mechanism is measured during the measurement. Serial detected as the calibration value at operation amount sensor, a scanning probe microscope calibration method, which comprises carrying out the actual sample measurement using a calibration value obtained by the operation amount sensor. 2. The method for calibrating a scanning probe microscope according to claim 1, wherein the reference sample has a lattice pattern in which a highly precise pitch is defined in at least one direction. 3. The reference sample is tilted at a known angle on the sample table so that the one direction in which the pitch is determined matches the tilt direction, and the sine value of the pitch is used to determine the height direction. 3. The method for calibrating a scanning probe microscope according to claim 2, wherein the calibration value is obtained. 4. The method for calibrating a scanning probe microscope according to claim 3, wherein the sine value of the pitch is a value having nano-order accuracy. 5. A sample table on which a sample is placed, a cantilever having a probe facing the sample, a triaxial fine movement mechanism for mounting the cantilever and displacing the relative position of the probe and the sample. A displacement detection device for detecting the displacement of the cantilever and an operation amount sensor for detecting the operation amount of the triaxial fine movement mechanism, and the probe and the probe while scanning the surface of the sample by the triaxial fine movement mechanism. A calibration standard used in a scanning probe microscope that detects a deflection amount of the cantilever based on a physical amount acting between samples by the displacement detection device and controls the deflection amount to measure the surface of the sample. And having a grid pattern in which a highly precise pitch is defined in at least one direction, and the one direction in which the pitch is defined is tilted on the sample table. The scanning probe microscope is characterized by using a reference sample tilted at a known angle so as to match the direction, and the sine value of the pitch is used as a reference distance for obtaining a calibration value in the height direction. Calibration standard. 6. A tilted block having a tilted surface of a known angle is prepared on the sample table, and the reference sample is placed on the tilted surface of the tilted block so that the one direction and the tilt direction of the tilted block coincide with each other. The calibration standard for a scanning probe microscope according to claim 5, wherein 7. The calibration standard for a scanning probe microscope according to claim 5, wherein the sine value of the pitch is a value having nano-order accuracy. 8. A sample table on which a sample is placed, a cantilever having a probe facing the sample, a triaxial fine movement mechanism for mounting the cantilever and displacing the relative position of the probe and the sample. A displacement detection device for detecting the displacement of the cantilever and an operation amount sensor for detecting the operation amount of the triaxial fine movement mechanism, and the probe and the probe while scanning the surface of the sample by the triaxial fine movement mechanism. In a scanning probe microscope that detects a deflection amount of the cantilever based on a physical amount acting between samples with the displacement detection device and controls the deflection amount to measure the surface of the sample, high precision in at least one direction. And a reference sample for measuring a calibration value, which has a grid pattern with a fixed pitch, and the reference sample has the one direction in which the pitch is defined as an inclination direction. It matches the labels, characterized in that it comprises an arrangement means for arranging tilted to the sample table in the scanning probe microscope. 9. The scanning probe microscope according to claim 8, wherein the arranging means is an inclined block having an inclined surface with a known inclination angle.