JP2001324438A - Spm maintenance/management method and computer- readable recording medium having program for making computer execute the method recorded therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an SPM maintenance/management method for facilitating calibration of an SPM probe control mechanism and evaluation of a probe. SOLUTION: A standard sample with a known cycle pitch, e.g. a collective body of reference resin balls with a minute particle size of not larger than 1 μm or the like is set (step S101). Surface observation data is obtained for the standard sample (step S102). A cycle pitch of the reference resin balls in a designated range (step S105) is calculated from the obtained surface observation data (step S106). Thereafter, when the operated cycle pitch does not agree with the actual known cycle pitch, a control amount in the XY plane directions of an actuator for minutely moving the probe to the sample is corrected, on the basis of a quantity of the cycle pitch difference (step S108).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an SPM (Scanning Probe M) for observing a minute area (on the order of nanometers) of a sample surface using a sharpened probe.
The present invention relates to an SPM maintenance management method for performing maintenance management such as calibration of a probe control mechanism and evaluation of a probe, and a computer-readable recording medium storing a program for causing a computer to execute the method.

[0002]

2. Description of the Related Art At present, a scanning tunneling microscope (STM: Scanning Tuning Microscope) is used as a microscope for observing a minute region on the order of nanometers on a sample surface.
Neeling Microscope, Atomic Force Micros (AFM)
Cope) and a scanning near-field optical microscope (SNOM:
Scanning Near-field Optic
al Microscope) and the like.

All of these microscopes scan a sample surface using a sharpened probe.
Scanning probe microscope (SPM: Scanni)
ngProbe Microscope).

For example, the above-mentioned AFM uses a cantilever provided with a probe at the tip, and scans the probe of the cantilever along the surface of the sample to be observed, and moves the probe between the sample surface and the probe. The shape of the surface of the sample is measured by detecting the interatomic force (attraction or repulsion) generated in the cantilever as the amount of bending of the cantilever.

As described above, the SPM measures the interaction between the probe and the sample surface by bringing the probe close to the sample surface, and correlates the data obtained by the measurement with the position information that is changed by the scanning control of the probe. Two-dimensional or three-dimensional image information is obtained. Therefore, the measurement sensitivity and the resolution of the obtained image information greatly depend on the state of the probe tip used.

For example, the radius of curvature at the tip of the probe is small,
If the sample is ideally sharpened by one atom, the sample surface can be observed in atomic or molecular units, and a clear image can be obtained even when the observation range is on the order of several nanometers. In contrast, when the tip has a large radius of curvature and there are many atoms that can interact with the tip close to the sample surface, or when there are a plurality of sharp points at the tip (a so-called double The tip) cannot obtain a clear image even if the observation range is on the order of several nanometers, and the observation range needs to be larger.

Therefore, in the collection of sample surface data by SPM, in an extreme case, different observation data may be obtained before and after exchanging the probe even if the same observation target is used. Causes a problem in the reproducibility of. Therefore, when a probe is replaced, generally, a sample called a standard sample, which has a periodic surface structure, is first observed, and the state of the probe is evaluated based on whether known observation data can be obtained accurately. That is being done.

Further, the probe may be defective during observation due to adhesion of dust or breakage due to collision with the sample. In particular, when a gel-like soft material is used as an observation sample or when observation is performed in a submerged atmosphere, the above-described deterioration of the probe is remarkable. Therefore, in such a case, replacement of the probe frequently occurs, and it is necessary to evaluate the probe with the above-described standard sample every time the probe is replaced.

Regarding the shape of the probe, before mounting the probe on the SPM, a scanning electron microscope (SEM) is used.
It was a practical means to learn by observing with a Ctron Microscope).

[0010]

However, in the prior art, one of the above-mentioned standard samples, which has a lattice structure of about 2 to 3 μm on its surface, is one of the reasons that it is easily available. However, the probe could not be evaluated based on the observation result on the order of nanometer, which can be called the characteristic of SPM.

Prior to mounting the probe on the SPM, in addition to the above-mentioned SEM, devices for evaluating the probe based on the result of observation of a very sharp structure have been developed. A device capable of evaluating the state of the probe requires a long time for observation, and has a problem in that the probe is generally made of silicon (Si), and thus is likely to be damaged by a high-energy beam.

In the SPM, when the tip of the probe has a distorted shape, a distorted image depending on the tip shape is obtained in principle. However, when the probe is mounted on the SPM, Since the shape of the probe cannot be grasped, the above-described distortion cannot be removed.

Further, in the SPM, the probe is slightly displaced in the XYZ directions by a driving device such as a piezoelectric actuator. Due to this, the probe movement amount due to the control value of the piezoelectric actuator may deviate from the actual probe deviation amount, especially in a minute range such as on the order of nanometers, and it is necessary to calibrate the probe control value. There was a problem that there is.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and uses an aggregate of reference resin balls having a diameter of 1 μm or less, which is easily available, as a standard sample. The present invention provides an SPM maintenance management method for calibrating a probe control mechanism of an SPM and evaluating a probe, and a computer-readable recording medium storing a program for causing a computer to execute the method. The purpose is.

[0015]

Means for Solving the Problems To solve the above-mentioned problems,
In order to achieve the object, the SPM maintenance management method according to the first aspect of the present invention provides an SPM (Scan) for finely moving a stage or a probe on which a sample is mounted in a horizontal plane direction (XY directions).
In an SPM maintenance management method for calibrating a control value of an actuator of a Ning Probe Microscope), observation data of a surface microstructure of a standard sample having a periodic structure of a known size is acquired for a standard sample having a periodic structure of a known size.
Deriving the periodic pitch of the standard sample from the acquired observation data, comparing the derived periodic pitch with the known periodic pitch of the standard sample, and comparing the results, the derived periodic pitch and the known periodic pitch of the standard sample Is different, it is determined that calibration of the control value of the actuator is necessary.

According to the first aspect of the present invention, the conventional SP
While maintaining the device configuration of M, acquire surface observation data of a standard sample having a periodic pitch of a known size, and calibrate the control value of the actuator using the periodic pitch information indicated by the acquired surface observation data. It can be determined whether or not it is necessary.

In the SPM maintenance management method according to a second aspect of the present invention, in the first aspect of the present invention, the derivation of the periodic pitch is obtained by performing a differentiation process on the acquired observation data, and obtained by the differentiation process. The observation is performed by setting a position in the XY direction plane where a peak in the vertical direction (Z direction) of the observation data exceeds a predetermined value as a boundary position that defines the periodic pitch.

According to the second aspect of the present invention, the boundary position defining the periodic pitch in the observation data is emphasized by differentiating the obtained observation data, and the vertical direction (Z) obtained by the emphasis is obtained. The periodic pitch can be derived by determining that it is a boundary position only at a position (in the XY direction plane) where the peak in the (direction) exceeds a predetermined value.

In the SPM maintenance management method according to the third aspect of the present invention, in the first or second aspect of the present invention, when it is determined that calibration of the control value of the actuator is necessary, the derived periodic pitch and A difference from a known periodic pitch of the standard sample is calculated, and a control value of the actuator in the X and Y directions is calibrated based on the difference.

According to the third aspect of the invention, the control value of the actuator in the X and Y directions can be calibrated based on the difference between the derived periodic pitch and the known periodic pitch of the standard sample.

According to a fourth aspect of the present invention, there is provided an SPM maintenance management method for calibrating a control value of an actuator for finely moving a stage or a probe for mounting a sample in a vertical direction (Z direction). Obtain observation data of the surface microstructure of the standard sample for a standard sample having a step of size, derive the step of the standard sample from the obtained observation data, and derive the step and the known step of the standard sample. And when the derived step is different from the known step of the standard sample, it is determined that the control value of the actuator needs to be calibrated.

According to the invention of claim 4, the conventional SP
It is necessary to acquire surface observation data of a standard sample having a step of a known size while retaining the apparatus configuration of M, and to calibrate the control value of the actuator using the step information indicated by the acquired surface observation data. It can be determined whether or not there is.

According to a fifth aspect of the present invention, in the SPM maintenance management method according to the fourth aspect of the present invention, when it is determined that calibration of the control value of the actuator is necessary, the derived step and the standard sample are determined. And calculating a difference between the actuator and a known step, and calibrating a control value of the actuator in the Z direction based on the difference.

According to the fifth aspect of the present invention, the control value of the actuator in the Z direction can be calibrated based on the difference between the derived step and the known step of the standard sample.

Further, the SPM maintenance management method according to the invention of claim 6 uses the SPM equipped with a probe to be evaluated, with respect to a standard sample having a valley of a known depth. Obtaining the observation data of the surface microstructure, deriving the depth of the valley of the standard sample from the obtained observation data, based on the result of comparing the derived depth and the known depth of the standard sample, The method is characterized in that the shape of the tip such as the aspect ratio and the radius of curvature of the probe is determined.

According to the sixth aspect of the present invention, a standard sample having a valley of a known depth is observed with the probe to be evaluated attached to the SPM, and the standard sample derived from the observation data is observed. Using the depth information of the valley of the sample, the shape of the tip of the probe (the aspect ratio, the radius of curvature, etc.) can be determined.

According to a seventh aspect of the present invention, there is provided the SPM maintenance management method according to any one of the first to sixth aspects, wherein the standard sample is an aggregate of particles having a known particle size. Features.

According to the seventh aspect of the present invention, since the aggregate of particles having a known particle size is used as the standard sample, the characteristics of the finely packed structure formed by the spherical aggregate and the sizes in the XY and Z directions are both reduced. By utilizing a spherical characteristic such as equality, both the periodic pitch and the step can be known as known sizes.

In a computer readable recording medium according to the present invention, a program for causing a computer to execute any one of the methods according to the first to seventh aspects is recorded. The program becomes machine-readable, so that the operation according to the method of claims 1 to 7 can be realized by a computer.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an SPM maintenance management method according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited by the embodiment.

(Embodiment 1) First, an SPM maintenance management method according to Embodiment 1 will be described. Embodiment 1
The SPM maintenance management method according to the above uses an aggregate of reference resin balls as a standard sample, and based on the observation results,
Of the probe or stage control mechanism (XYZ actuator).

Here, as the standard resin ball, highly reliable standard particle size particles having high traceability of the National Institute of Standards and Technology (NIST) are commercially available. For example, polystyrene particles having a particle size of 500 nm are converted into pure water. It is provided in a dispersed form. Therefore, by developing the above-described reference resin ball on a flat material (for example, a wall-opened surface of a layered polycrystalline material or a silicon [111] surface) that can ignore a fine surface shape on the order of nanometers. In addition, many of the reference resin balls can be self-formed into a more stable densely packed structure. The present embodiment is characterized in that an aggregate of reference resin balls in the form of the finely packed structure is used as a standard sample.

FIG. 1 is a flowchart showing a method of calibrating the SPM probe control mechanism in the SPM maintenance management method according to the first embodiment. Note that the SPM for realizing the present method has the same configuration as the conventional one, and here, XYZ
On a stage that can be finely moved in the Z-axis direction (vertical direction) and XY direction (in a horizontal plane) by an actuator,
The description will be made assuming that the sample is set and the probe is fixedly arranged above the stage. That is, the control value of the XYZ actuator is a calibration target in the present method.

The SPM is the same as that of the prior art.
Control means for controlling the SPM operation such as driving of the YZ actuator and detection of interaction (atomic force etc.) between the probe and the sample surface, and a general user interface (input means such as a keyboard and a mouse, a CRT display, etc.) And a computer for giving instructions such as the start of measurement and the measurement range to the control means described above via the display means). In particular, the method can be provided as a program executable on the computer.

First, in carrying out the present method, a user sets a standard sample, which is an aggregate of reference resin balls, on the above-mentioned stage (step S101), and mounts a probe at a predetermined position. The mounting of the probe can be completed before the setting of the standard sample, depending on the SPM device configuration.

In this state, the user instructs the start of the calibration operation via the above-mentioned user interface to start the process of acquiring and displaying the surface observation data for the standard sample (step S102). The acquisition of the surface observation data is the same as the acquisition of the surface observation data for a normal sample. (1) Automatic approach of the probe to the surface of the standard sample, (2) Probe scanning in the XY directions after completion of the automatic approach. (Actually, the stage moves) (3) Detection of interaction (atomic force or the like) between the probe and the sample surface and Z-axis feedback control of the probe (actually, the stage is controlled), (4) 2) The detected interaction amount is imaged in two or three dimensions.

FIG. 2 is a diagram showing an example of a three-dimensional image of the surface structure of the standard sample displayed in step S102. As shown in FIG. 2, the reference resin balls each having a separable spherical shape are stable in a finely packed structure. In particular, FIG.
Shows that the reference resin ball is spread almost uniformly in the direction within the XY plane.

Subsequently, the user designates an axis to be calibrated among the X, Y, and Z axes of the XYZ actuator (step S103). The designation of the calibration axis may be performed at a stage prior to the process of step S102. Here, first, the case where the calibration axis specified by the user is the X axis or the Y axis, that is, the case where the calibration is performed in the horizontal plane direction will be described (No in step S104). In particular, in the following, a case where the X axis is designated will be described as an example.

Next, the user designates a range to be used as the calibration reference data, that is, a range of a set of standard samples on the displayed image of the surface structure in which the periodic pitch is to be obtained (step S105). Specifically, as shown in FIG. 3A, the three-dimensional image shown in FIG.
On a two-dimensional display image on a plane, for example,
A plurality of reference resin balls in series are designated like the line A '.

FIG. 3B is a cross-sectional view of the reference resin ball arrangement in the range of the line AA ′ designated in FIG.
That is, it is a diagram showing data in the Z-axis direction. FIG.
As shown in (b), it can be seen that the reference resin ball arrangement along the line AA 'is arranged at a substantially constant pitch.
As shown in FIGS. 2 and 3, on the computer which is a part of the SPM device configuration, after acquiring the surface observation data of the sample, a three-dimensional structure or a two-dimensional structure by a combination of desired axes is obtained. In addition, surface observation data can be processed in a free display form.

When the designation of the calibration reference data is completed in step S105, the periodic pitch of the reference resin balls is calculated based on the data in the designated range (step S106). Here, when calculating the periodic pitch of the reference resin balls, if the cross-sectional data as shown in FIG. 2B is used as it is, the boundary between the reference resin balls is unclear, so that an accurate result is obtained. Can not get. Therefore, by performing a differentiation process on the acquired surface observation data, data in which the valleys between the reference resin balls are emphasized is created.

FIG. 4 is a diagram showing the result of performing a differentiation process on the three-dimensional image shown in FIG. As shown in FIG. 4, the portion located at the boundary between the reference resin balls is emphasized and represented as an edge peak by the differential processing.
FIGS. 5 (a) and 5 (b) are diagrams showing the results of performing differentiation processing on FIGS. 3 (a) and 3 (b), respectively.
As a result of the differentiation processing, the cross section taken along the line AA ′ in FIG.
As shown in FIG. 5B, the reference resin balls can be easily separated by the edge peak.

For example, as shown in the figure, a reference level TL is set in the Z-axis direction, and a point where an edge peak exceeds the reference level TL is determined as a boundary position. In the case where the reference level TL intersects at two points on the cross section of the same reference resin ball, it is more negative.
An intersection on the X-axis side can be selected as a boundary position, or a center point between two points can be set as a boundary position.

By specifying the boundary positions between the reference resin balls in this manner, the distance d between the boundary positions can be recognized as the periodic pitch of the reference resin balls as shown in the figure.
Here, the pitch calculated by the above-described procedure should originally match the known particle size of the reference resin ball. It can be considered that the movement amount of the XYZ actuator is different, and it can be determined that correction is necessary.

Therefore, based on the shift amount, the control value for instructing the movement for the pitch is corrected to a value for performing the movement for the known particle size (step S10).
8). Thereby, the control value calibration of the XYZ actuator is realized even in a minute range of 1 micrometer or less such as the particle diameter of the reference resin ball.

In the pitch calculation described above, the arrangement direction of the adjacent reference resin balls does not always coincide with the X axis for driving the XYZ actuator.
Even if they do not match, the specified calibration reference data range
There is no problem because it is easy to separate the component into the Y component.

Next, in step S103, when the Z axis is designated as the axis to be calibrated (step S103).
104 affirmation) will be described. In this case, the computer extracts, from the surface observation data obtained in step S102 or the newly obtained surface observation data, a range in which a step corresponding to one reference resin ball occurs in the Z-axis direction. One height data is acquired (step S107).

FIG. 6 is an explanatory diagram for explaining acquisition of height data for one reference resin ball. In FIG. 6, for ease of understanding, the flat material 60 described above is used.
A state where only one layer of the reference resin ball 65 is unfolded is shown above. As shown, in the scanning of the probe,
From the probe 61 whose tip is located at the top of the reference resin ball 65 to the probe 6 whose tip is located on a flat material 60
At 1 ', a displacement of 2R of the particle diameter of the reference resin ball is theoretically observed.

Therefore, in the calibration in the Z-axis direction, first, a difference between the data in the Z-axis direction acquired at the position of the probe 61 and the data in the Z-axis direction acquired at the position of the probe 61 ′ is obtained. Is determined, and it is determined whether or not this difference matches the particle diameter 2R of the known reference resin ball. When they do not match, it is considered that the fine movement control amount of the XYZ actuator in the Z-axis direction by the feedback control needs to be corrected, and the probe 61 and the probe 61 ′ are determined based on the deviation amount.
Is corrected so that the control value instructing the movement corresponding to the distance in the Z-axis direction between the respective positions becomes a value for performing the movement by the known particle diameter 2R (step S108).

As described above, according to the SPM maintenance management method according to the first embodiment, a reference resin ball having a small particle size of 1 micrometer or less is used as a standard sample and developed into a close-packed structure. By performing a differentiation process on the surface observation data obtained for the obtained reference resin ball, the periodic pitch of the reference resin ball can be easily and accurately calculated from the obtained surface observation data, and the calculated value is calculated. It is necessary to calibrate the control value in the XY plane direction of the XYZ actuator for finely moving the probe with respect to the sample by judging whether or not the result matches the actual known particle diameter of the reference resin ball. It is possible to determine whether the obtained surface observation data is accurate even in a minute range such as 1 micrometer or less. It can be Tokusuru.

When it is determined that it is necessary to calibrate the control values of the XYZ actuators in the XY plane direction, based on the deviation between the calculated result and the actual known particle diameter of the reference resin ball, Since the control value of the XYZ actuator is corrected so that the control value instructing the movement for the arrangement pitch becomes a value for performing the movement for the known particle diameter, a minute range such as 1 micrometer or less is corrected. Also in the above, calibration in the XY plane direction of the XYZ actuator can be performed, and more accurate surface observation data can be obtained.

Further, a displacement in the Z-axis direction corresponding to the height of one reference resin ball is acquired, and it is determined whether or not the acquired displacement matches the actual known particle diameter of the reference resin ball. By doing so, it is possible to determine whether or not it is necessary to calibrate the control value of the XYZ actuator in the Z-axis direction, so that it is possible to know whether or not the Z-axis feedback control is being performed accurately. .

Further, when it is determined that the control value of the XYZ actuator in the Z-axis direction needs to be calibrated, the deviation amount between the acquired displacement in the Z-axis direction and the actual known particle diameter of the reference resin ball is determined. Based on the above, the control value instructing the movement corresponding to the displacement is corrected so as to be a value for performing the movement for the known particle size, so that the calibration of the XYZ actuator in the Z-axis direction can be performed. It is possible to obtain more accurate surface observation data.

In the first embodiment described above,
Although the standard sample was described as a spherical reference resin ball,
The differential processing for easily and accurately calculating the pitch and the acquisition of the step in the Z-axis direction can be applied to a sample having a lattice structure on the surface or a conventional standard sample having a known step size. it can.

(Embodiment 2) Next, an SPM maintenance management method according to Embodiment 2 will be described. The SPM maintenance management method according to the second embodiment uses an assembly of the above-described reference resin balls as a standard sample, and evaluates a probe based on the observation result.

FIG. 7 is an explanatory diagram for explaining a probe evaluation method in the SPM maintenance management method according to the second embodiment. In particular, FIG. 7 shows a state in which a plurality of reference resin balls 75 are developed in a one-layer close-packed structure on a flat material 70 that can ignore a fine surface shape on the order of nanometers.

In FIG. 7, the probes 71 and 71 'are
The tip portion has a relatively large aspect ratio (a value indicated by a1 / b1 in the figure), and the probe 72
Is the aspect ratio of the tip (a2 / b2 in the figure)
Is relatively small.

Here, as shown in FIG. 7, when the reference resin balls are arranged in a finely packed structure, the probe 71 is scanned along the surface of the plurality of reference resin balls 75.
The position in the Z-axis direction at the apex of the valley between the reference resin balls obtained by this scanning (the position of the probe 71 'in the figure) is the position in the Z-axis direction at the top of the reference resin ball (in the figure,
Ideally, there should be a difference with respect to the position of the probe 71) by a value R which is exactly half the particle diameter.

However, since the tip of the probe 71 has a spread defined by the above-mentioned aspect ratio even though it is minute, its tip cannot reach the top of the valley between the reference resin balls. Therefore, as shown in the figure, the difference between the position in the Z-axis direction at the top of the valley and the position in the Z-axis direction at the top of the head is actually a result of subtracting the error α from the half value R of the particle diameter. Is obtained.

Accordingly, this error becomes larger as the above-mentioned probe has a smaller aspect ratio, and in FIG.
2, the error α when using the probe 71 ′ is used.
, An error β having a larger value is generated. This means
This means that the observation data of the top and the valley in the Z-axis direction of the reference resin ball differs according to the difference in the aspect ratio of the tip of the probe, and this is used to shape the tip of the probe. Can be evaluated.

The difference in valley data due to the probe is caused not only by the difference in aspect ratio but also by whether or not the tip has a distorted shape. This is because if the tip of the probe is distorted, it is highly likely that the tip will come into contact with the surface of the reference resin ball on both sides before the tip reaches deep into the valley of the reference resin ball. I do.

Further, the difference in the valley data depending on the probe also depends on the radius of curvature of the tip of the probe. FIG. 8 is an explanatory diagram for describing a radius of curvature of a probe located at a valley of a reference resin ball. As shown in FIG. 8, when the radius of curvature r of the probe 81 is small, the probe 81 can reach a deeper valley between the reference resin balls 85, but when the radius of curvature r is large, Will remain at a position far away from the top of the valley.

As a specific method of evaluating the probe, for example, a table is prepared in which the reachable position of the reference resin ball in the valley direction obtained from the theoretical calculation is associated with the shape of the probe. The shape of the tip of the probe is evaluated by referring to this table with respect to the actually obtained observation data.

In this case, the difference between the actually obtained observation data in the Z-axis direction at the valley between the reference resin balls and the observation data at the top of the reference resin ball is smaller than a predetermined value. Alternatively, the fact that the probe is defective can be displayed on the display means.

As described above, according to the SPM maintenance management method according to the second embodiment, a reference resin ball having a small particle size of 1 micrometer or less is used as a standard sample and developed into a close-packed structure. Since the shape of the probe can be evaluated based on the surface observation data in the Z-axis direction acquired at the valleys between the reference resin balls, the probe is mounted on the SPM and the SPM is used. The quality of the probe can be easily determined.

In the second embodiment,
Although the observation data at the valley between the reference resin balls was used to evaluate the probe, information on the lower half of the reference resin ball cannot usually be obtained in principle from the shape of the probe. In addition, since the shape is acquired as a flared shape as shown by a dotted line 69 in FIG. 6, a change in observation data according to the tip shape of the probe also appears according to the degree of spread of the skirt. Therefore, the degree of spread of the skirt can be used as evaluation information of the probe.

A computer program for realizing the SPM maintenance management method according to the first or second embodiment described above is stored in a recording medium such as an IC card memory, a floppy (registered trademark) disk, a magneto-optical disk, or a CD-ROM. And by installing the program recorded on this recording medium as firmware or software in a computer constituting the SPM, the functions realized by the SPM maintenance management method according to the present invention can be realized in the conventional SPM device. Can be provided.

[0068]

According to the first, second and seventh aspects of the present invention, a standard sample having a known periodic pitch, for example, an aggregate of reference resin balls having a fine particle diameter of 1 micrometer or less is prepared. By performing differential processing on the surface observation data acquired for the standard sample used, the periodic pitch of the reference resin ball can be easily and accurately derived from the acquired surface observation data, By judging whether or not the result obtained and the actually known pitch match each other, it is determined whether or not it is necessary to calibrate the control value in the XY plane direction of the actuator for slightly moving the probe with respect to the sample. Since it is possible to judge, even in a minute range such as 1 micrometer or less, it is possible to know whether or not the obtained surface observation data is accurate. Unlikely to.

According to the third aspect of the present invention, when it is determined that the control value of the actuator in the XY plane direction needs to be calibrated, the derived result is compared with the actual known period pitch. Based on the amount of deviation, the control value of the actuator can be corrected so that the control value instructing the movement of the periodic pitch becomes a value for performing the movement of the known periodic pitch. Calibration in the XY plane directions can be realized,
There is an effect that it is possible to acquire more accurate surface observation data.

According to the fourth and seventh aspects of the present invention, a standard sample having a known step (for example, a reference resin ball having a known particle size) is used, and the step (height) is used.
And the displacement in the Z-axis direction corresponding to
By judging whether or not an actual known step coincides, it is judged whether or not it is necessary to calibrate the control value of the actuator in the Z-axis direction. Therefore, the Z-axis feedback control is performed accurately. This has the effect of being able to know whether or not it is running.

According to the fifth aspect of the present invention, when it is determined that the control value of the actuator in the Z-axis direction needs to be calibrated, the acquired displacement in the Z-axis direction is compared with the actual known value. Based on the amount of deviation from the step, the control value instructing the movement corresponding to the displacement can be corrected so as to be a value for performing the movement of the known step. This has the effect that calibration can be realized and more accurate surface observation data can be obtained.

According to the invention described in claim 6, a standard sample having a valley of a known depth (for example, a reference resin ball having a known particle size) is used, and the valley of the standard sample is used. The shape of the probe can be evaluated based on the acquired surface observation data in the Z-axis direction.
There is an effect that it is possible to easily determine the quality of the probe using the SPM while attached to the PM.

Further, according to the invention described in claim 8,
By recording a program for causing a computer to execute the above-described method according to claims 1 to 7, the program becomes machine-readable, whereby the operation according to the method according to claim 1 to 7 can be realized by a computer. There is an effect that a recording medium having a small size can be obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a method of calibrating an SPM probe control mechanism in an SPM maintenance management method according to a first embodiment.

FIG. 2 is a diagram showing an example of a three-dimensional image of a surface structure of a reference resin ball developed in a finely packed structure in the SPM maintenance management method according to the first embodiment.

FIG. 3 is a diagram showing an example of a two-dimensional image of a surface structure of a reference resin ball developed in a close-packed structure in the SPM maintenance management method according to the first embodiment.

FIG. 4 is a diagram showing a result of performing a differentiation process on a three-dimensional image representing a surface structure of a reference resin ball developed into a finely packed structure in the SPM maintenance management method according to the first embodiment.

FIG. 5 is a diagram showing a result of performing a differentiation process on a two-dimensional image representing a surface structure of a reference resin ball developed into a finely packed structure in the SPM maintenance management method according to the first embodiment.

FIG. 6 is an explanatory diagram for describing acquisition of height data for one reference resin ball in the SPM maintenance management method according to the first embodiment.

FIG. 7 is an explanatory diagram for explaining a probe evaluation method in the SPM maintenance management method according to the second embodiment.

FIG. 8 is an explanatory diagram for describing a radius of curvature of a probe located at a valley of a reference resin ball in the SPM maintenance management method according to the second embodiment.

[Explanation of symbols]

 61, 61 ', 71, 71', 72, 81 Probe 65, 75, 85 Reference resin ball

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F069 AA60 AA66 DD30 FF00 FF07 GG01 GG04 GG06 GG07 GG62 GG72 HH02 HH04 HH30 JJ07 LL03 LL10 MM32 NN05 NN10 QQ05

Claims (8)

[Claims] An SPM (Scan) for finely moving a stage or a probe for mounting a sample in a horizontal plane direction (XY directions).
In the SPM maintenance management method for calibrating the control value of the actuator of the Ning Probe Microscope), observation data of the surface microstructure of a standard sample having a periodic pitch of a known size is acquired from the acquired observation data. Deriving the periodic pitch of the standard sample, comparing the derived periodic pitch with the known periodic pitch of the standard sample, and comparing, when the derived periodic pitch is different from the known periodic pitch of the standard sample, An SPM maintenance management method, wherein it is determined that calibration of the control value of the actuator is necessary. 2. The derivation of the periodic pitch is performed by differentiating the acquired observation data, and a vertical (Z direction) peak of the observation data obtained by the differentiation processing exceeds a predetermined value in an XY plane. The SPM maintenance management method according to claim 1, wherein the position is set as a boundary position that defines the periodic pitch. 3. When it is determined that calibration of a control value of the actuator is necessary, a difference between the derived periodic pitch and a known periodic pitch of the standard sample is calculated, and the actuator is determined based on the difference. 3. The SPM maintenance management method according to claim 1, wherein the control values in the X and Y directions are calibrated. 4. A SPM maintenance management method for calibrating a control value of an SPM actuator for finely moving a stage or a probe on which a sample is mounted in a vertical direction (Z direction), wherein the standard sample having a step of a known size is calibrated. Obtain observation data of the surface microstructure of the standard sample, derive the step of the standard sample from the obtained observation data, compare the derived step with a known step of the standard sample, and compare the derived step to the derived step. SPM maintenance management method, characterized in that it is determined that calibration of the control value of the actuator is necessary when the known step of the standard sample is different from the known step. 5. When it is determined that calibration of the control value of the actuator is necessary, a difference between the derived step and a known step of the standard sample is calculated, and the Z of the actuator is calculated based on the difference. The SPM maintenance management method according to claim 4, wherein the control value in the direction is calibrated. 6. Obtaining observation data of a surface microstructure of a standard sample having a valley of a known depth using an SPM equipped with a probe to be evaluated, and obtaining the obtained observation. Deriving the depth of the valley of the standard sample from the data, based on the result of comparing the derived depth with the known depth of the standard sample, the tip of the probe such as the aspect ratio or the radius of curvature of the tip, etc. An SPM maintenance management method characterized by determining a shape of a part. 7. The SPM maintenance management method according to claim 1, wherein the standard sample is an aggregate of particles having a known particle size. 8. A computer-readable recording medium on which a program for causing a computer to execute the method according to claim 1 is recorded.