JP2006138655A - Scanning probe microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanning probe microscope capable of obtaining precise measurement data by eliminating noise component characteristically arises only in specific scanning direction of the measurement device. <P>SOLUTION: The scanning probe microscope comprises: the cantilever 14 provided with prove 13; the moving mechanisms 11 and 17 for relatively moving the position of the probe to the sample 10; the detection means for detecting the specific physical amount; the measurement means for measuring the surface of the sample; and the measurement control means 60 for controlling the operation of the moving mechanisms and the measurement means. The measurement control means comprises: the scanning direction setting means 61 for setting the first scanning direction and the second scanning direction crossing at an arbitrary angle; the measurement performing means 62 for obtaining the measurement data by measuring the surface of the sample while scanning and moving the probe in the first scanning direction and the second scanning direction; the first subtraction means 63 for operating the difference of data between the first line data and the second line data; and the second subtraction means 64 for subtracting the above data difference from the measurement data concerning the first scanning direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a scanning probe microscope, and more particularly to a scanning probe microscope suitable for increasing the accuracy of a measurement value of a line or a surface obtained by scanning a measurement range of a sample surface with a probe.

  An example of a scanning probe microscope (SPM) is an atomic force microscope (AFM). The atomic force microscope has a cantilever that is supported by a cantilever structure and has elasticity and causes deformation of bending or twisting. A probe (probe) is provided at the free end of the cantilever. When measuring the surface of the sample, the probe is brought into contact with or close to the surface of the sample, and the measurement range is scanned linearly or planarly. When scanning the probe along the sample surface, it detects the deformation of the cantilever that deforms according to the atomic force between the probe and the sample, which changes according to the shape change of the sample surface and electrical specification, By processing this detection information in association with the position information of the probe, the shape or property of the sample surface can be measured.

  Information such as the uneven shape of the sample surface usually includes information on the height direction assigned to the Z axis and information on the XY plane direction assigned to the X axis and the Y axis. The information in the height direction is obtained by a Z-axis moving mechanism that changes so as to keep the relationship between the tip of the probe and the sample surface constant corresponding to the displacement of the cantilever. Information in the XY plane direction is obtained by an X-axis and Y-axis moving mechanism that relatively moves the probe and the sample.

  A mechanical moving mechanism or a piezo element is used to move the probe in the XY plane direction. In principle, the mechanical movement mechanism has inherently non-linearity of the operation due to environmental factors such as drifting factors (cause of temporal changes), the effects of backlash and sliding parts friction, temperature changes and humidity changes. ing. The piezo element has non-linearity in operation due to hysteresis inherent in the element. Furthermore, the non-linearity of the moving mechanism tends to increase with the deterioration of the device such as aging.

  The non-linear operation characteristics of the moving mechanism in the atomic force microscope are constant with respect to the scanning direction of the sample or the probe with respect to measurement data such as the plane position information of the probe on the sample surface and the corresponding height position information. As a characteristic noise that appears only in the scanning direction, it affects.

There is a method described in Patent Document 1 as a method of removing the noise as described above from measurement data obtained by measurement with an atomic force microscope. In this method, measurement scanning data related to a part of the sample and reference scanning data related to a reference image of a part of the sample are obtained by measurement using a scanning probe microscope, and the reference scanning data is subtracted from the measurement scanning data. The data for obtaining the corrected image is obtained.
International Publication Number: WO099 / 15851 (Patent Publication 2001-517777)

  According to the noise removal method of Patent Document 1 described above, when the above-described measurement scan data and reference scan data are obtained on the basis of a sample, when measuring each of the measurement sample portion and the reference sample portion, The characteristic characteristic noise that appears only in a certain scanning direction is superimposed at random. For this reason, the noise superimposed when measuring the reference sample portion may be different from the noise superimposed when measuring the measurement sample portion. As a result, there is a problem that even if the subtraction process is performed using the reference scan data, it is not effective for reliably removing noise inherent in the constant scan direction superimposed on the measurement scan data.

  Furthermore, since the sample to be measured and the reference sample are basically different, there is a problem that a difference in properties between the two samples may be reflected in the calculation result.

  Accordingly, an object of the present invention is to make it possible to remove, with high accuracy, characteristic noise that appears only in a certain scanning direction, such as a sample, from measurement data of a sample to be measured.

  In view of the above problems, an object of the present invention is to remove noise components that appear only in a certain scanning direction of the apparatus from measurement data related to a line or surface obtained by a measuring apparatus of a scanning probe microscope, Another object of the present invention is to provide a scanning probe microscope capable of obtaining high measurement data.

  In order to achieve the above object, a scanning probe microscope according to the present invention is configured as follows.

  A first scanning probe microscope (corresponding to claim 1) includes a cantilever having a probe provided at a free end, and a moving mechanism (XY fine movement mechanism, XYZ stage) for changing the position of the probe relative to a sample. ), Detection means for detecting a physical quantity acting between the probe and the sample, and a physical quantity detected by the detection means when the probe scans the surface of the sample by moving the probe relative to the moving mechanism. Measuring means for measuring the surface of the sample by using the measurement means, and a measurement control means for controlling the operation of the moving mechanism and the measuring means. The measurement control means intersects the positional relationship between the sample and the probe at an arbitrary angle. Scanning direction setting means for setting the first scanning direction and the second scanning direction, and each of the first scanning direction and the second scanning direction set by the scanning direction setting means within the measurement range set on the surface of the sample. Move the probe to scan A measurement execution means for measuring the surface and obtaining measurement data; arbitrary first line data among measurement data in the first scanning direction; and first data corresponding to the first data line in measurement data in the second scanning direction. First subtracting means for calculating the data difference between the two line data and second subtracting means for subtracting the data difference from the measurement data in the first scanning direction. Here, the arbitrary angle at which the first scanning direction and the second scanning direction intersect with each other includes 0 °.

  In the above scanning probe microscope, when the measurement data includes a noise component that appears characteristically in the scanning direction at the time of measurement (first scanning direction) due to environmental factors as described later, Measurement is performed by setting the second scanning direction not including the noise component, and the noise component is calculated based on the difference between the arbitrarily selected first line data and second line data, and the noise component is subtracted from the original measurement data. Thus, highly accurate measurement data from which characteristic noise components have been removed is acquired.

  In the second scanning probe microscope (corresponding to claim 2), in the first apparatus configuration described above, preferably, the first scanning direction is a specific direction in which a characteristic noise component is generated, and the second scanning direction is It is characterized by a specific direction in which no characteristic noise component occurs. Accordingly, characteristic data relating to characteristic noise can be obtained as difference data by using two measurement data having different scanning directions.

  The third scanning probe microscope (corresponding to claim 3) is preferably characterized in that, in each of the above-described device configurations, an arbitrary angle formed between the first scanning direction and the second scanning direction is 90 °. When characteristic noise such as a scanning mechanical system occurs due to environmental factors such as temperature and humidity, data with the least noise in the perpendicular direction can be obtained.

  In the fourth scanning probe microscope (corresponding to claim 4), in each of the above-described apparatus configurations, preferably, surface data is obtained by measurement in the first scanning direction by the measurement execution unit, and the first data is obtained from the surface data. It is characterized by selecting line data and acquiring line data corresponding to the second line data by measurement in the second scanning direction by the measurement execution means.

  In the fifth scanning probe microscope (corresponding to claim 5), preferably, in each of the above-described device configurations, the scanning direction setting means rotates the sample arrangement state by an arbitrary angle within the same plane. It is. The above two different scanning directions can be realized by changing the arrangement state such as the position and posture of the sample by the sample rotating mechanism.

  In the sixth scanning probe microscope (corresponding to claim 6), preferably, in each of the above-described device configurations, the scanning direction setting means sets the second scanning direction in substantially the same direction as the first scanning direction. And scanning execution means for performing high-speed scanning in the first scanning direction. By increasing the scanning speed in the first scanning direction, measurement in the second scanning direction that does not include drift noise such as temperature can be quickly performed with a simple configuration without rotating the sample.

  A seventh scanning probe microscope (corresponding to claim 7) is preferably characterized in that, in each of the above-described device configurations, the first line data and the second line data are the same number. With this configuration, it is possible to obtain more accurate measurement data from which characteristic noise components are removed. By increasing the number of first line data and second line data for calculating noise, noise corresponding to each place in the measurement range can be obtained, and the accuracy of measurement data can be increased.

  In the eighth scanning probe microscope (corresponding to claim 8), preferably, the number of scans, the scan pitch, and the first scan direction can be arbitrarily set in each device configuration described above. According to this structure, the freedom degree of a structure of a scanning probe microscope apparatus can be raised.

The present invention has the following effects.
(1) In measuring the surface characteristics of a sample with a scanning probe microscope such as an atomic force microscope, it is characterized by the scanning direction of the sample or probe derived from a scanning machine system or the like caused by environmental factors such as temperature conditions and humidity conditions The noise component can be easily removed from the measurement data on which typical noise is superimposed, and highly accurate measurement data and image data can be obtained.
(2) The process of removing noise components includes a step of calculating characteristic noise in the scanning direction of the sample or probe, which makes it easy to check whether the noise is superimposed on the measurement data. can do.
(3) In order to obtain measurement data using the same measurement location of the same sample, for example, when using a separate reference sample such as a standard test piece or referring to another location within the same sample Compared to the above, it is possible to perform noise removal which is less susceptible to variations in characteristics between samples.
(4) When a plurality of line data selected to extract a noise component are used, noise components at each location in the measurement range corresponding to each line data can be obtained, so measurement data with higher accuracy can be obtained. And image data can be obtained.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments (examples) of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 shows a typical embodiment of a scanning probe microscope according to the present invention, and shows a configuration of a main part of the scanning probe microscope. This scanning probe microscope is typically an atomic force microscope, but is not limited thereto.

  Reference numeral 10 is an enlarged view of a part of the sample to be measured. The sample 10 is placed on an XYZ stage 11 for sample movement. Here, X, Y, and Z indicate the three axes X, Y, and Z that form the three-dimensional coordinate system 12. The XYZ stage 11 is a coarse movement mechanism that moves the position of the sample 10 by a relatively large distance in the three-dimensional coordinate system 12. The XYZ stage 11 is generally made by an electric drive source and a mechanical configuration. The XYZ stage 11 includes an XY coarse movement mechanism and a Z coarse movement mechanism. The XYZ stage 11 is usually mounted on a reference table.

  The upper surface 10a of the sample 10 is an uneven surface to be measured. A probe 13 is arranged on the surface 10a of the sample 10 with its tip opposed. The probe 13 is provided at the free end of a cantilever 14 attached in a cantilever structure. In the cantilever 14, the base end is fixed to the cantilever mounting portion 15. The cantilever mounting portion 15 is provided in the Z-direction fine movement mechanism 16, and the Z-direction fine movement mechanism 16 is fixed to the XY fine movement mechanism 17. The XY fine movement mechanism 17 is fixed to a frame (not shown). The Z-direction fine moving mechanism 16 is a moving mechanism that moves the cantilever 14, that is, the probe 13 in the Z direction at a fine distance, and the XY fine movement mechanism 17 scans and moves the cantilever 14, that is, the probe 13 in the XY plane direction at a fine distance. It is a moving mechanism.

  On the upper side of the cantilever 14, a laser oscillator (laser light source) 18 and a photodetector 19 are provided. The laser beam 20 output from the laser oscillator 18 is applied to the back surface of the cantilever 14. The laser beam 20 is reflected by the back surface of the cantilever 14 and is incident on the light receiving surface of the photodetector 19 in principle. The light receiving surface of the photodetector 19 is divided into four parts and has four light receiving regions.

  The probe 13 is arranged to face the surface 10 a of the sample 10 in such a state that an atomic force acts between the tip of the probe 13 and the surface of the sample 10. The distance between the probe 13 and the sample 10 is controlled by a feedback servo control loop so that a predetermined atomic force is generated and maintained at a constant distance d. The feedback servo control loop is configured as follows.

  When bending deformation or the like occurs in the cantilever 14 due to the relationship between the sample 10 and the probe 13, the incident position of the laser beam 20 on the light receiving surface of the photodetector 19 changes. The detection signal Vd output from the photodetector 19 is input to the subtractor 21. The subtractor 21 calculates a deviation between the detection signal Vd and the reference value (Vref), and the deviation signal ΔV is input to the controller 22. The controller 22 supplies a control signal for adjusting the distance between the probe and the sample to the Z-direction fine movement mechanism 16 so that the deviation signal becomes zero. By setting the deviation signal output from the controller 22 to 0, control is actually performed so that the actual deflection amount of the cantilever 14 matches the reference deflection amount (reference value Vref) as a reference. .

  Reference numeral 23 denotes a displacement detector for detecting the Z-direction fine movement amount of the Z-direction fine movement mechanism 16. A control signal SG1 output from the controller 22 and a detection signal SG2 output from the displacement detector 23 are input to the controller 31 for control. In the controller 31, the control signal SG1 is handled as a detection signal, that is, measurement data in which the uneven shape of the surface 10a of the sample 10 is reflected.

  The host controller 32 has a function of controlling the measurement by controlling the operation of each moving mechanism such as the XYZ stage 11 and the XY fine moving mechanism 17 described above. The host controller 32 gives a control signal for instructing a scanning operation based on the XYZ stage 11 and a control signal for instructing a fine scanning operation based on the XY fine movement mechanism 17. These control signals for the moving operation output from the host controller 32 are also handled as measurement data in the host controller 32 in the same manner. Further, the host control device 32 creates image data of the sample surface based on the measurement data related to the Z direction and the measurement data related to the scanning position, and displays an image of the image created by the image data as a display device (monitor) 33. On the screen. The host control device 32 sets and saves automatic measurement conditions. Furthermore, the host controller 32 also has functions such as setting of basic items such as a measurement range and measurement speed, setting of probe scanning conditions at the time of pattern detection, management of those setting files, and communication with the outside. .

  The controller 31 and the host control device 32 control the operation of each moving mechanism such as the XYZ stage 11, the Z-direction fine moving mechanism 16, and the XY fine moving mechanism 17 described above, process control signals, and display processing of image data. By performing the above, it functions as a means for controlling the measurement.

  FIG. 2 shows an example of the mode of the scanning operation of the probe 13 that scans the surface 10a of the sample 10. FIG. 2A shows the operation principle of a fine measurement scanning mode (fine mode) for measuring a surface state in a minute range based on a continuous contact mode. FIG. 2B shows the principle of operation of the measurement scanning mode (wide mode) by coarse motion for measuring a large range of surface states based on the continuous contact mode. FIG. 2C shows the operation principle of the scanning mode (step-in mode) for measuring the surface state in a minute range based on the intermittent contact mode. Reference numeral 34 denotes a movement locus of the probe 13 in the step-in mode.

  In the fine mode scanning movement, each of the Z-direction fine movement mechanism 16 and the XY fine movement mechanism 17 operates. In the scanning movement in the wide mode, the Z direction fine movement mechanism 16 and the XY coarse movement mechanism section of the XYZ stage 11 operate. In the step-in mode scanning operation, each of the Z-direction fine movement mechanism 16 and the XY fine movement mechanism 17 operates.

  FIG. 3 shows an example of a scanning movement pattern of the probe 13 on the surface 10 a of the sample 10. Reference numeral 35 denotes a rectangular measurement range set on the surface 10a of the sample 10, for example. Reference numeral 36 denotes a trajectory pattern of the scanning movement of the probe 13 with respect to the measurement range 35. By operating each of the XY fine movement mechanism 17 and the XY coarse movement mechanism section of the XYZ stage 11, the Z-direction fine movement mechanism 16 changes the relative position of the probe 13 and the sample 10 based on the scanning movement in the XY direction. Thus, the bending amount of the cantilever 14 is controlled to be constant, and the characteristics such as the uneven shape of the sample surface are measured. For example, if a square area with a side of 20 mm is scanned at 1 mm / second by the coarse motion mechanism in the X direction, sent by 0.1 mm in the Y direction, and scanned by X, the measurement takes 1 hour or more, temperature in the order of nm, etc. Drift noise overlaps in the Y direction.

  Next, a characteristic measurement and image data creation method in the scanning probe microscope, that is, the atomic force microscope, according to the present invention will be described with reference to FIGS. According to this characteristic measurement and image data creation method, it is caused by the non-linear operation characteristics of the moving mechanism (scanning machine system) in the atomic force microscope apparatus described in the background art section. Then, measurement data and image data from which regular or random noise components characteristically appear only in a certain scanning direction with respect to the scanning direction of the sample or the probe are removed. 4 to 9 schematically show images of measurement data or image data, and FIG. 10 shows a processing procedure.

  FIG. 4 shows a waved surface state 41 with respect to the measurement range 35 on the surface of the sample 10. The surface state 41 that strikes this wave occurs in the Y-axis direction and does not occur in the X-axis direction. The waved surface state 41 shows an image created by image data obtained by measurement with an atomic force microscope apparatus having a characteristic mechanical nonlinearity in the scanning direction in the Y-axis direction. According to FIG. 4, the scanning movement in the Y-axis direction (first scanning direction) cannot be linearly moved, so that the moving mechanism is elastically bent and the height direction is displaced, and the Y-axis is displaced. A characteristic noise component has an influence on measurement data obtained by scanning in a direction. In FIG. 4, a range 42 indicates a further limited measurement region. First, the measurement range 42 is measured (step S11).

  FIG. 5 shows that the scanning direction of the probe 13 is typically rotated by 90 ° within a plane parallel to the scanning surface of the probe 13 in measuring the same measurement range portion of the sample shown in FIG. In step S12), measurement is performed by scanning the measurement range 43 with the same atomic force microscope apparatus in the scanning direction (second scanning direction) rotated by 90 ° (step S13), and based on the image data obtained by the measurement. It is an image figure. The second scanning direction intersects the first scanning direction at an angle of 90 °.

  Note that the rotation of 90 ° in the scanning direction (step S12) may be performed by providing a sample rotation mechanism to rotate the sample side, or by providing a probe rotation mechanism and rotating the probe side. Furthermore, it is possible to provide a scanning execution means that can scan at a relatively high speed in accordance with the scanning direction.

  The noise component that causes image distortion in the Y-axis direction, which is characteristic in FIG. 4, still appears in the Y-axis direction in the measurement data of the sample rotated 90 ° within the same measurement range in FIG. . From this, it is found that the distortion of the measurement data on the image is not unique to the sample 10 but is a characteristic noise component in the scanning direction in the Y-axis direction. In FIG. 5, a range 43 is a measurement region corresponding to the rectangular range 42 shown in FIG.

  Therefore, next, in the measurement data range 42 shown in FIG. 4, an arbitrary data line including a noise component characteristic in the Y-axis scanning direction, preferably parallel to the Y-axis scanning direction, is selected, Measurement data of the data line is obtained from the data measured in step S11 (step S14). FIG. 6 shows the selected data line 44.

  Further, in the range 43 of the measurement data shown in FIG. 5, the data line 45 corresponding to the data line 44 selected in FIG. 6 and corresponding to the same location on the sample 10 is selected, and the data measured in step S13 is selected. To obtain measurement data of the data line (step S15). This data line 45 is shown in FIG.

  The measurement data in the range 43 shown in FIG. 5 is a result of rotating the same sample 10 by 90 ° with respect to the measurement data in the range 42 shown in FIG. A data line 45 corresponding to the data line 44 in the range 43 is a data line having an angle of 90 ° with respect to the scanning direction in the Y-axis direction of the atomic force microscope apparatus, and is characteristic in the scanning direction in the Y-axis direction. This is a data line that does not contain a noise component.

  Therefore, as shown in FIG. 8, the measurement data (line data and Z direction measurement value) 52 related to the data line 45 is subtracted from the measurement data (line data and Z direction measurement value) 51 related to the data line 44. (Step S16), a data line as shown in 53 is obtained, and the numerical data (numerical data in the Z direction) indicated by the data line 53 appears characteristically in the Y-axis scanning direction of the atomic force microscope apparatus. Means noise component. By the subtraction process described above, only noise components that characteristically appear in the Y-axis scanning direction of the atomic force microscope apparatus according to the present embodiment are extracted.

  An arithmetic process (step S17) is performed to reduce noise characteristic of the scanning direction in the Y-axis direction extracted in the above procedure from the entire measurement data image shown in FIG. The calculation result is shown in the data schematic diagram of FIG. A range 55 is an image of the finally obtained image data 56 (step S18). Compared with FIG. 4, it can be seen that noise components characteristically generated in the scanning direction in the Y-axis direction are effectively removed.

  In the measurement method according to the above embodiment, the data selected in FIG. 4 in the arbitrary data line 44 selected from the measurement image shown in FIG. 4 and the measurement image in FIG. 5 obtained by rotating the scanning direction by 90 °. Although the calculation process is performed using the data line 45 corresponding to the line 44, it is also possible to perform the calculation process by measuring only one scanning line corresponding to the data line 45 after rotating the sample by 90 °. Is possible. In this case, the same effect can be obtained. According to this configuration, time for creating two images can be saved, and characteristic noise can be more easily removed.

  Furthermore, in the above embodiment, the direction in which the scanning direction is rotated by 90 ° is set as the second scanning direction. However, the present invention is not limited to this, and an arbitrary direction in which characteristic noise does not appear may be set as the second scanning direction. Even if the second scanning direction is the same as the first scanning direction, the time component drift noise can be removed by performing high-speed scanning in the second scanning direction.

  When there is a fine uneven pattern such as an LSI wafer, if the position of the unevenness does not match between data lines with different scanning directions, noise is generated. In order to prevent this, a filter such as 10 μm area averaging is applied to the measurement data itself of the data line so as to reduce the influence of unevenness. The filter size is preferably larger than the alignment accuracy between the data lines, and if the unevenness of the wafer is larger than the required accuracy, a sufficient filter for reducing this is necessary. On the other hand, there is a restriction on the filter size that is smaller than the frequency component of the corrected noise. Since these are the effects of the filter, the required size and the number of filtering points increase as the required accuracy increases. In many cases, it is more practical to decide experimentally.

  FIG. 11 shows a functional block configuration diagram of functions of measurement control means realized by the controller 31 and the host controller 32 that enable the measurement method (noise removal method) in the atomic force microscope. The means 60 for measuring control includes a first scanning direction 71 (for example, the Y-axis direction) and a second scanning direction 72 (for example, a direction orthogonal to the Y-axis direction) that intersect at an arbitrary angle with respect to the positional relationship between the sample 10 and the probe 13. And the scanning direction setting means 61 for scanning the probe 13 in each of the first scanning direction and the second scanning direction set by the scanning direction setting means 61 within the measurement range set by the surface 10a of the sample 10. The measurement execution means 62 that moves and measures the sample surface to obtain measurement data, arbitrary first line data among the measurement data in the first scanning direction, and first data in the measurement data in the second scanning direction First subtracting means 63 for calculating the data difference between the second line data corresponding to the line and second subtracting means 64 for subtracting the data difference from the measurement data in the first scanning direction are provided.

  In the above, the scanning direction setting means 61 may be a sample rotation mechanism that rotates the arrangement state of the sample by an arbitrary angle within the same plane, or in the second scanning direction as compared with the first scanning direction. Alternatively, it may be a scanning execution unit that performs relatively high-speed scanning. In the above-described scanning probe microscope or the like, the number of scans, the scan pitch, and the first scan direction can be arbitrarily set.

  In the above-described embodiment, the number of data lines (44, 45) is one, but the number of data lines is not limited to this. For example, a plurality of lines such as 4 or 8 can be set. The positional relationship between the plurality of data lines in the first scanning direction and the plurality of data lines in the second scanning direction correspond to each other. If processing is performed so as to obtain characteristic noise components at each location using a plurality of data lines and remove characteristic noise components according to the location from the measurement data related to the measurement range in the first scanning direction. Further, highly accurate measurement data (image data) can be obtained.

  Specifically, when the left, middle, and right lines (81, 82, 83) in the X direction among a plurality of data lines are compared, it is considered that there is a twist or a difference in the way of swell. It is done. This is shown in FIG. 12 (A) twist and (B) swell. The characteristic noise components as these surfaces cannot be corrected only by the middle data line 82 but can be corrected by a plurality of lines 81-83. Interpolation (for example, approximate curve) is performed between these plural data, but the calculation method is selected depending on the nature of the characteristic noise to be corrected originally. It is efficient to perform the interpolation calculation after the noise is calculated in each data line and subtract the noise from the original surface.

  The configurations, shapes, sizes, and arrangement relationships described in the above embodiments are merely shown to the extent that the present invention can be understood and implemented, and the numerical values and the compositions (materials) of the respective configurations are as follows. It is only an example. Therefore, the present invention is not limited to the described embodiments, and can be variously modified without departing from the scope of the technical idea shown in the claims.

  INDUSTRIAL APPLICABILITY The present invention is used for accurately extracting characteristic noise appearing in the scanning direction due to environmental factors in measurement of a sample surface with a scanning probe microscope and removing the noise from the obtained measurement data. .

It is a block diagram which shows the apparatus structure of the scanning probe microscope which concerns on this invention. It is a figure which shows three types of scanning modes of the probe which scans the sample surface. It is a perspective view which shows an example of the scanning locus | trajectory in the measurement range on the sample surface. It is a perspective view which shows an example of the state of the sample surface in which characteristic noise has arisen in the scanning direction of a Y-axis direction, and a measurement range. It is a perspective view which shows the example of the state of a sample surface at the time of setting a scanning direction to the direction which cross | intersects at 90 degrees in a Y-axis direction, and another measurement range. It is a figure which shows the example of selection of the 1st data line in the state in FIG. It is a figure which shows the example of selection of the 2nd data line in the state of FIG. It is a characteristic view which shows each change characteristic of the 1st and 2nd data line, and the characteristic change characteristic of noise. It is a figure which shows an image with the measurement data from which the characteristic noise was removed. It is a flowchart which shows the process of removing noise. It is a functional block diagram which shows the characteristic structure of the scanning probe microscope which concerns on this invention. It is a figure explaining the characteristic noise which concerns on a multiple data line process, (A) is a figure which shows a twist, (B) is a figure which shows a wave.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sample 11 XYZ stage 13 Probe 14 Cantilever 16 Z direction fine movement mechanism 17 XY fine movement mechanism 22 Controller 31 Controller 32 Host controller 44 Data line 45 Data line

Claims (8)

A cantilever having a probe provided at a free end, a moving mechanism for relatively changing the position of the probe with respect to a sample, a detecting means for detecting a physical quantity acting between the probe and the sample, and A measuring means for measuring the surface of the sample using the physical quantity detected by the detecting means when the probe scans the surface of the sample by moving the probe relatively by a moving mechanism; In a scanning probe microscope comprising the movement mechanism and a measurement control means for controlling the operation of the measurement means,
The measurement control means includes
A scanning direction setting means for setting a first scanning direction and a second scanning direction that intersect at an arbitrary angle with respect to a positional relationship between the sample and the probe;
Within the measurement range set on the surface of the sample, measure the sample surface by scanning the probe in each of the first scanning direction and the second scanning direction set by the scanning direction setting means, A measurement execution means for obtaining measurement data;
Calculate a data difference between arbitrary first line data among the measurement data in the first scanning direction and second line data corresponding to the first data line among the measurement data in the second scanning direction. First subtracting means,
Second subtracting means for subtracting the data difference from the measurement data in the first scanning direction,
A scanning probe microscope characterized by the above.   2. The scanning probe microscope according to claim 1, wherein the first scanning direction is a specific direction in which a characteristic noise component is generated, and the second scanning direction is a specific direction in which no characteristic noise component is generated. .   The scanning probe microscope according to claim 1 or 2, wherein the arbitrary angle formed by the first scanning direction and the second scanning direction is 90 °.   Surface data is acquired by the measurement in the first scanning direction by the measurement execution unit, the first line data is selected from the surface data, and the second in the measurement in the second scanning direction by the measurement execution unit. The scanning probe microscope according to claim 1, wherein line data corresponding to the line data is acquired.   2. The scanning probe microscope according to claim 1, wherein the scanning direction setting means is a sample rotating mechanism that rotates the arrangement state of the sample by the arbitrary angle within the same plane.   The scanning direction setting unit is a scanning execution unit that sets the second scanning direction in substantially the same direction as the first scanning direction and performs high-speed scanning in the first scanning direction. The scanning probe microscope according to claim 1.   2. The scanning probe microscope according to claim 1, wherein the first line data and the second line data are the same number. The scanning probe microscope according to claim 1, wherein the number of scans, the scan pitch, and the first scan direction can be arbitrarily set.

Images