JP2007240238A - Probe microscope and measuring method of probe microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe microscope capable of reducing probe damage when positioning a probe and a sample on a measuring domain, and performing proper and stable measurement by suppressing a resolution change caused by a probe tip shape. <P>SOLUTION: In this probe microscope wherein a cantilever 23 for coarse motion having a probe 21 for coarse motion on the tip and a cantilever 24 for measurement having a probe 22 for measurement on the tip are constituted, after positioning is performed on a sample measuring domain by the probe 22 for coarse motion, the probe 21 for rough motion is once separated from the sample surface measuring domain by a cantilever conversion means for changing the distance between the probe 21 for rough motion and the sample surface of the probe 22 for measurement, and switched to the probe 22 for measurement, and then, the probe 22 for measurement is positioned on the sample measuring domain to perform the measurement. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a probe microscope for measuring shape information such as surface roughness and level difference on a sample surface, and physical information such as dielectric constant and viscoelasticity, and a measuring method of the probe microscope.

In recent years, probe microscopes such as an atomic force microscope having atomic resolution have been expected as shape measurement for evaluation of fine shapes. Atomic Force Microscope (AFM), a kind of probe microscope, is an inventor of Scanning Tunneling Microscope (STM). Since it was devised by Binnig et al., It is expected to be a means for observing the surface shape of a novel insulating material, and research has been conducted. (For example, see Non-Patent Document 1)
The principle of the probe microscope is that the physical force acting between the probe with a sufficiently sharp tip and the sample is measured as the displacement of the spring element to which the probe is attached, so that the displacement amount of the spring element is kept constant. The surface of the sample is scanned, and the shape of the surface of the sample is measured using shape information as a control signal for keeping the amount of displacement of the spring element constant.

  As the displacement detection means of the spring element, there are an optical system and a self-detection system that detects a deformation strain of the spring element as an electric signal.

  An example using the so-called interferometry itself as an optical method (for example, see Non-Patent Document 2), or irradiating a spring element with laser light and detecting the displacement of the reflected light by a light detection element An example called an optical lever method (see, for example, Non-Patent Document 3), which is used as a signal, has been reported, and is mainly used as a detection method of a probe microscope.

Further, in recent years, a lever portion provided with a probe at the tip and a support portion for supporting the lever portion are connected by two bent portions, and the bent portion is formed as a piezoresistor forming region, and two piezoresistors are formed. A self-detecting method is known in which a cantilever is controlled by measuring a resistance value difference indicating a displacement difference between both bent portions caused by twisting of the cantilever between bodies. (For example, see Patent Document 1.)
A probe microscope is called an atomic force microscope if a probe (probe) disposed at a position facing the sample receives an atomic force from the sample, and a magnetic force microscope if the probe is magnetic. In this way, the state of the sample can be observed by detecting various forces generated from the sample.

  An example of a schematic system configuration of the probe microscope will be described with reference to FIG.

  The sample 3 to be measured is disposed on a fine movement mechanism 4 that moves the sample in three dimensions. The fine movement mechanism 4 uses a piezoelectric element that deforms when a voltage is applied, and finely positions the sample 3 with respect to the probe 1 arranged at a position opposite to the sample. The probe 1 is formed at the tip of a cantilever beam called a cantilever 2.

  An example of the shape of a general cantilever is shown in FIG. A cantilever substrate 25 is provided with a cantilever-like cantilever 2, and a fine probe (probe) 1 having a quadrangular shape and a height of 1 to 2 μm is formed at the tip of the cantilever 2. The cantilever substrate 25, the cantilever 2, and the probe 1 are made of silicon or a silicon-based material, and are processed as a single body using an anisotropic etching technique or the like.

  The cantilever substrate 25 having the cantilever 2 is held by the cantilever holder 13.

  The fine movement mechanism 4 is configured on a coarse movement mechanism 5 including a stage or the like for moving the sample 3 and the probe 1 three-dimensionally. Here, the coarse movement mechanism 5 is a screw feed mechanism driven by a stepping motor.

  On the cantilever 2 side, a displacement detection system 6 for detecting the deformation of the cantilevered beam material by a physical quantity force such as an atomic force received by the probe 1 from the sample surface is configured. The displacement detection system 6 is composed of a semiconductor laser 7 that irradiates the back surface of the cantilever 2 and a four-divided photodetector 8 that detects the reflected light, and a position that enters the photodetector due to the displacement of the cantilever 2. A method called optical lever detection is used to detect the displacement (deflection deformation) of the cantilever by changing.

  The signal from the photodetector 8 is sent via an amplifier 9 to a Z-axis control feedback circuit 10 that controls the Z-axis (vertical direction) distance between the sample 3 and the probe 1, and the fine movement mechanism 4 is operated to probe the probe. The Z-axis positional relationship between 1 and the sample 3 is controlled. In-plane scanning of the probe 1 and the sample 3 is performed by scanning the fine movement mechanism with a signal from the XY drive circuit 11. The Z-axis control, XY drive, and the like are controlled by the computer and the control system 12.

  The probe 1 at the tip of the cantilever 2 is brought closer to the surface of the sample 3 using the coarse movement mechanism 5. When the displacement detection system 6 detects the deformation of the cantilever 2 due to the atomic force, magnetic force, viscoelasticity, or other physical force received by the probe 1 from the surface of the sample 3 and reaches a predetermined deformation, the measurement region It is determined that the probe 1 is positioned, and the coarse movement mechanism 5 is stopped, and the Z-axis of the fine movement mechanism 4 that moves the sample 3 and the probe 1 relative to each other on the sample side or the cantilever side is moved. Control to maintain the surface distance of the probe 1 and the sample 3, and while controlling the Z axis of the fine movement mechanism 4, the coarse movement mechanism 5 is driven to adjust the displacement amount of the Z axis of the fine movement mechanism 4, The probe 1 and the surface of the sample 3 are positioned. The deformation value of the cantilever 2 is controlled to be constant, and the fine movement mechanism 4 is measured while scanning the sample surface to visually visualize the shape and physical properties in the sample surface.

By using a rough movement mechanism 5 to bring the probe 1 and the surface of the sample 3 close to each other, the deformation of the cantilever 2 is detected by some physical quantity such as the atomic force that the probe 1 receives from the surface of the sample 3. When the mechanism 5 is stopped and the surface distance of the probe 1 and the sample 3 is controlled by the fine movement mechanism 4, the distance between the probe 1 and the sample 3 is confirmed by means such as an optical microscope when the probe 1 and the sample 3 are brought close to each other. And a method of changing the vibration amplitude amount in the vibration mode have been known (for example, see Patent Documents 2 and 3). (For example, see Patent Document 4)
Here, the coarse movement mechanism 5 uses a stage including a stepping motor which is a step feed. Therefore, when the follow-up response of the fine movement mechanism 4 to the Z-axis (vertical direction) is not fast enough, the fine movement mechanism 4 may detect the probe after the tip of the probe 1 comes into contact with the surface of the sample 3 depending on the coarse movement state. The distance between the needle 1 and the surface of the sample 3 may be controlled. When the probe 1 is in contact with the sample 3 even a little, the tip of the probe 1 is deformed, and the measurement resolution may be lowered in a probe microscope in which the shape of the tip of the probe 1 affects the resolution. Moreover, when the surface of the sample 3 is a material softer than the probe 1, there is a problem that the surface of the sample 3 may be damaged.

  Further, when the operating speed of the coarse movement mechanism 5 is slowed, the possibility that the probe 1 comes into contact is reduced, but it takes a long time to position the probe 1 in the sample 3 measurement region.

  In addition, while driving the fine movement mechanism 4 and other moving mechanisms to search for approaching the sample measurement area, the coarse movement mechanism 5 is operated to perform a so-called worming operation to position the probe in the sample measurement area. There is a way to do it. (For example, refer to Patent Documents 5, 6, and 7.) This method is also a method of operating the coarse movement mechanism at a stroke by driving the fine movement mechanism and other movement mechanisms. It takes time to drive and to search, depending on the setting conditions.

Therefore, there is a need for a probe microscope that can be positioned and measured without damaging the probe 1 in the sample 3 measurement region (for example, atomic force) and without requiring much time for alignment. ing.
G. Binnig, CF Quate and Ch. Gerber, Atomic Force Microscope, “Physical Review Letters”, American, Physical Society, 1986, Vol. 56, No. 9, p.931 R. Erlandsson, GM McClelland, CM Mate, and S. Chiang, Atomic force microscopy using optical interferometry, “Journal of Vacuum Science Technology”, Mar / Apr 1988, A6 (2), pp. 266-270 S. Alexander, L. Hellemans, O. Marti, J. Schneir, V. Elings, and PK Hansma, Matt Longmire and John Gurley, An atomic-resolution atomic-force microscope implemented using an optical lever, “Journal of Applied Physics” 1989, 65 (1), pp. 164-167 JP 2000-111563 A JP-A-5-18743 JP-A-7-198729 JP 2005-164278 A Japanese Patent No. 3169227 Japanese Patent Laid-Open No. 1-186742 JP 2002-372488 A

  The present invention solves the above-mentioned problems, can position the probe in the measurement region on the sample surface without greatly increasing the measurement time, and has a resolution due to the probe tip shape due to the broken probe. An object of the present invention is to provide a probe microscope capable of reducing changes and stably performing high-resolution measurements.

  The present invention provides the following means in order to solve the above problems.

The probe microscope of the present invention is a probe microscope that measures shape information or physical information of a sample surface by bringing a probe close to or in contact with the sample surface,
A measuring cantilever having a measuring probe at the tip, and a coarse cantilever having a coarse probe at at least one tip;
A cantilever conversion means for controlling the distance of the coarse movement probe from the measurement probe to the sample surface;
The sample surface was measured in a state where the measurement probe of the measurement cantilever was approaching or contacting the sample surface while the measurement probe was closer to the sample surface than the coarse probe.

  The probe configured for the cantilever is brought close to the sample measurement area (for example, atomic force), and the probe for coarse movement and the probe for measurement are configured. The probe for coarse movement is positioned in the sample measurement area. After that, by means of controlling the distance between the cantilever and the sample, the coarse movement probe is once separated from the sample surface measurement region, switched to the measurement probe, and the measurement probe is positioned in the sample measurement region. .

  By configuring coarse probe and measurement probe, positioning in the sample measurement area with coarse probe, and then switching to measurement probe, without damaging the tip of measurement probe. Thus, it is possible to position the sample measurement surface without delaying the conventional positioning time.

  As a result, measurement can be performed without changing the tip shape of the measurement probe before measurement, so that stable measurement resolution can be obtained. In addition, it is possible to provide a probe microscope that leads to reproducibility and stability of measurement results and improved reliability of measurement results.

  Hereinafter, a first embodiment of a probe microscope according to the present invention will be described with reference to FIGS. 1 to 3. In the following embodiments, the same reference numerals are given to the same basic configuration as the schematic system configuration of the probe microscope described in FIG. 10, and the description thereof is omitted.

  FIG. 1 is a configuration diagram of a cantilever of a probe microscope according to the first embodiment of the present invention.

  The cantilever substrate 25 includes a coarse movement cantilever 23 and a measurement cantilever 24, each of which has a coarse movement probe 21 and a measurement probe 22, which are integrated using silicon as a material. Is formed.

  FIG. 2 is a front view showing the positional relationship between the cantilever and the sample measurement surface of the probe microscope according to the first embodiment of the present invention. The coarse cantilever 23 and the measurement cantilever 24 differ in angle with respect to the surface of the sample 3 between the coarse motion and the measurement, and the sample 3 measurement surface of the coarse motion probe 21 and the measurement probe 22 are compared with each other. Changing the distance.

  FIG. 3 is an example of a configuration diagram illustrating a cantilever holder portion of the probe microscope according to the first embodiment of the present invention.

  A cantilever substrate 25 having a coarse cantilever 23 and a measuring cantilever 24 is fixed to an inclined block 26 provided on the cantilever holder 13 by using a fixing spring 27. The cantilever holder 13 is provided with a hole 28 disposed above the cantilever holder for allowing the laser beam of the displacement detection system 6 using an optical lever mechanism to pass through and observing the cantilever from above with an optical microscope or the like. When the inclined portions 29 on both side surfaces of the cantilever holder 13 are installed on the probe microscope main body, they are inserted into the dovetail grooves provided on the probe microscope main body side for positioning.

  The cantilever holder 13 has a handle 30 for easy handling.

  A tilt mechanism 31 is configured on the tilt block 26 provided on the cantilever holder 13. The tilt mechanism 31 serves as a cantilever conversion means for controlling the distance relationship between the measurement probe 22 and the coarse movement probe 21 with respect to the sample surface. As the tilt mechanism 31, a laminated piezoelectric material was used. Alternatively, when the displacement amount of the single layered piezoelectric body is not sufficient, the lever can be used to reduce the displacement of the piezoelectric body at the cantilever mounting portion using the piezoelectric body as the power point and the cantilever mounting portion as the action point. You may comprise what is called a displacement expansion mechanism to expand.

  The drive of the tilt mechanism 31 is wired to the main body of the probe microscope via the tilt mechanism wiring 48 and is controlled by a control mechanism (not shown). The tilt mechanism 31 is provided at a position eccentric with respect to the direction perpendicular to the longitudinal direction of the coarse movement cantilever 23 and the measurement cantilever 24 of the cantilever substrate 25, and the tilt mechanism 31 is driven to move the cantilever substrate 25 to one side of the cantilever substrate 25. By changing the pushing amount, the cantilever substrate 25 is twisted to change the posture of the coarse movement probe 21 of the coarse movement cantilever 23 and the measurement probe 22 of the measurement cantilever 24 with respect to the sample surface, thereby changing the coarse movement probe 21. Either one of the measurement probes 22 can be selected to project either one from the sample surface.

  In addition, unlike the measurement probe 22, the tip of the coarse movement probe 21 used during coarse movement does not require resolution, so even if the radius of curvature is relatively large and the sample and the probe are in contact during coarse movement, By reducing the contact pressure per unit area to the sample surface, scratches on the sample surface are reduced.

  A measurement method in the probe microscope using the thus configured cantilever will be described below.

  First, the tilting mechanism 31 is driven so that the coarse motion probe 21 side projects from the measurement probe 22 with respect to the surface of the sample 3 with the coarse motion mechanism 5. Coarse movement is performed to bring the sample 3 close to the distance. When the displacement detection system 6 detects a deformation of the coarse cantilever 23 caused by an atomic force, a magnetic force, a physical force such as viscoelasticity, etc. received by the probe 1 from the surface of the sample 3 and the deformation reaches a predetermined value. The coarse movement mechanism 5 is stopped, and the Z-axis of the fine movement mechanism 4 that moves the sample 3 and the coarse movement probe 21 that are configured on the sample side is controlled to control the distance between the coarse movement probe 21 and the surface of the sample 3. The fine movement mechanism 4 controls the Z-axis direction while driving the coarse movement mechanism 5 to adjust the amount of displacement of the fine movement mechanism 4 in the Z-axis, so that the coarse movement probe 21 and the surface of the sample 3 are adjusted. The position is brought close to or in contact with the predetermined distance. Next, the fine movement mechanism 4 provided on the sample side is moved in the direction of separating the distance between the sample 3 and the coarse movement probe 21 once to move in the Z-axis direction. Next, the tilting mechanism 31 is driven so that the measurement probe 22 protrudes from the coarse movement probe 21 so as to approach the sample 3. Next, the fine movement mechanism 4 is used to further reduce the distance between the measurement probe 22 and the surface of the sample 3, and when the deformation of the measurement cantilever 24 reaches a predetermined value, the deformation value becomes constant. By controlling and measuring the fine movement mechanism 4 while scanning the sample surface, the shape and physical properties in the sample surface are visually imaged.

  As a result, the measurement probe 22 is positioned in the measurement region on the surface of the sample 3, so that there is no great difference between the coarse movement mechanism and the coarse movement time, and the probability that the measurement probe is damaged is reduced. Measurement with a microscope can be performed, and the measurement result can be stabilized.

  In the present embodiment, the detection of the fluctuation of the coarse movement cantilever 23 and the measurement cantilever 24 is switched using one displacement detection system 6, but two displacement detection systems are used for detecting the fluctuation of each cantilever. It may be provided.

  In addition, using a coarse probe with a relatively large tip radius, when positioning between the sample surface and the probe, the pressure per unit area on the sample is reduced, thereby reducing damage to the sample. Can be reduced.

  The coarse movement probe 21 is used to scan the fine movement mechanism 4 with respect to the sample surface while controlling the coarse movement probe 21 and the surface of the sample 3 so as to approach or contact each other and maintain a predetermined distance. The measurement conditions such as the measurement area, scanning speed, and control conditions are determined before measurement using the measurement probe 22 by visually measuring the shape and physical properties in the sample surface. After carrying out, measurement may be performed with a measuring probe. This can further reduce damage to the measurement probe.

  In addition, by making the measurement probe 22 conductive by forming a metal film using a plating method or a sputtering method, the measurement probe 22 can perform electrical measurement with the sample surface. If a magnetic film is similarly formed on the surface of the measurement probe 22 so as to have magnetism, the magnetic probe may be configured to be capable of magnetic measurement.

  Further, regarding the measurement of the shape of the sample surface, a cylindrical probe is formed on the measurement probe 22 so that measurement can be performed even for a sample having a deep shape.

  In addition, even with a measurement probe that is suitable for deep shape measurement but has a large aspect ratio (ratio of length to thickness), which is considered to be weak against impact, this measurement is performed after coarse movement is performed with the coarse movement probe. In order to position the probe for measurement on the surface of the sample, the probe can be positioned on the sample surface without relatively impacting the probe, so that the rate of breakage of the measurement probe having a large aspect ratio can be reduced.

  Next, a second embodiment of the probe microscope apparatus according to the present invention will be described with reference to FIGS.

  In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 4 is a configuration diagram of a cantilever of a probe microscope according to the second embodiment of the present invention.

  This embodiment is an example of so-called vibration mode measurement that detects fluctuations in vibration frequency and vibration amplitude by receiving physical quantities such as atomic force from the sample surface by vibrating near the resonance frequency of the cantilever. is there.

  A coarse cantilever 23 having a coarse movement probe 21 at its tip and a measurement cantilever 24 having a measurement probe 22 at its tip are formed on a cantilever substrate 25. Here, the coarse motion cantilever 23 has a resonance frequency of about 130 KHz, and the measurement cantilever 24 has a resonance frequency of about 300 KHz, which is different from the resonance frequency.

  FIG. 5 is an example of a configuration diagram showing a cantilever holder portion of the probe microscope according to the second embodiment of the present invention.

  The cantilever substrate 25 is fixed to an inclined block 26 provided on the cantilever holder 13 using a fixing spring 27. The cantilever holder 13 is provided with a hole 28 disposed above the cantilever holder for allowing the laser beam of the displacement detection system 6 using an optical lever mechanism to pass through and observing the cantilever from above with an optical microscope or the like. When the inclined portions 29 on both side surfaces of the cantilever holder 13 are installed on the probe microscope main body, they are inserted into the dovetail grooves provided on the probe microscope main body side for positioning.

  Between the inclined block 26 and the cantilever holder 13, a vibration piezoelectric plate 32 made of a piezoelectric element for vibrating the coarse movement cantilever 23 and the measurement cantilever 24 is formed. The vibration piezoelectric plate 32 is wired to a power source (not shown) via the vibration plate wiring 49 and applies a control voltage to the vibration piezoelectric plate 32.

  A measurement method in the probe microscope using the thus configured cantilever will be described below.

  First, the vibration piezoelectric plate 32 is vibrated by applying a control voltage so as to have the resonance frequency of the coarse movement cantilever 23, thereby vibrating the coarse movement cantilever 23 and the measurement cantilever 24. As a result, the coarse movement cantilever 23 has a larger amplitude than the measurement cantilever 24. In this state, coarse movement is performed by the coarse movement mechanism 5 to reduce the distance between the coarse movement probe 21 and the sample 3, and the physical force such as the atomic force, magnetic force, viscoelasticity, etc. received by the probe 1 from the surface of the sample 3 is performed. When the deformation of the coarse motion cantilever 23 is detected by the displacement detection system 6 and the deformation reaches a predetermined value, the coarse motion mechanism 5 is stopped, and the sample 3 and the coarse motion probe configured on the sample side are stopped. The Z-axis of the fine movement mechanism 4 that relatively moves 21 is controlled to maintain the surface distance between the coarse movement probe 21 and the sample 3. The fine movement mechanism 4 controls the coarse movement mechanism 5 while controlling the Z-axis direction. By driving, the amount of displacement of the Z-axis of the fine movement mechanism 4 is adjusted so that the position of the coarse movement probe 21 and the surface of the sample 3 is brought close to or in contact with each other to be a predetermined distance. Next, the fine movement mechanism 4 provided on the sample side is moved in the direction of separating the distance between the sample 3 and the coarse movement probe 21 once to move in the Z-axis direction. Next, the vibration piezoelectric plate 32 is vibrated by applying a control voltage so as to have the resonance frequency of the measurement cantilever 24, thereby causing the coarse movement cantilever 23 and the measurement cantilever 24 to vibrate. As a result, the measuring cantilever 24 has a larger amplitude than the coarse movement cantilever 23. As a result, the measuring cantilever 24 has a larger amplitude than the coarse movement cantilever 23. Next, in this state, the Z-axis of the fine movement mechanism 3 is operated, and the distance between the probe 1 and the surface of the sample 3 is further reduced, and the deformation of the measuring cantilever 24 is detected while being detected by the displacement detection system 6. When the value reaches the value, the deformation value is controlled to be constant, and the fine movement mechanism 4 is measured while scanning the sample surface, thereby visualizing the shape and physical properties in the sample surface.

    In this way, the control voltage of the vibration piezoelectric plate 32 is changed to each resonance frequency, thereby providing the cantilever conversion means.

  Next, a third embodiment of the probe microscope apparatus according to the present invention will be described with reference to FIGS.

In the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and the description thereof is omitted.
In this embodiment, a so-called self-detecting cantilever that detects deformation of the cantilever as a change in resistance value is used.

  A self-detecting cantilever has a cantilever with a tip at the tip and a dummy cantilever without a tip at the tip, and each cantilever is provided with a resistance layer made of a piezo element, which can be used to deform the cantilever with a probe. By detecting the accompanying change in resistance value, the deformation of the cantilever due to the physical quantity acting between the probe and the sample is detected. This is the so-called Wheatstone bridge circuit used in strain gauges.

  FIG. 6 is a configuration diagram of a cantilever of a probe microscope according to the third embodiment of the present invention.

  A cantilever 23 for coarse movement having a probe 21 for coarse movement at the tip, a measurement cantilever 24 having a probe 22 for measurement at the tip, and a dummy resistor 41 having no probe at the tip are formed on a cantilever substrate 42. Yes. Further, thermal resistors 40 are formed on the coarse motion cantilever 23 and the measurement cantilever 24, respectively. The cantilever substrate 42 is affixed to the substrate 43, and the self-detection signal wiring 45 between the cantilever substrate 42 and the substrate 43 is connected by the mold portion 44.

  FIG. 7 is an example of a configuration diagram showing a cantilever holder portion of the probe microscope according to the third embodiment of the present invention.

  The probe microscope using the cantilever of this embodiment is the same as the probe microscope described in the first embodiment except that the displacement detection system 6 by optical lever detection is not required.

  The substrate 43 is held by being inserted into a cantilever mount 47 provided on the cantilever holder 13. At this time, when the contact in the cantilever mount 47 and the contact electrode 46 of the substrate 43 are in contact with each other, detection and control are performed from the probe microscope via the wiring 50 configured in the cantilever holder 13.

Further, the cantilever holder 13 is provided with a hole 28 for observing the state of the cantilever with an optical microscope or the like from above, and both sides of the inclined portion 29 of the cantilever holder 13 for positioning when installed on the probe microscope main body, The cantilever holder 13 is fixed by being inserted into a dovetail groove provided on the probe microscope side. In addition, the handle 30 is configured so as to be easy to handle. A measurement method in a probe microscope using the cantilever configured as described above will be described below.

  First, a current is passed through the thermal resistor 40 of the measurement cantilever 24, and the measurement cantilever 24 is warped by the heat generated by the resistor, so that the coarse movement probe side 21 is closer to the sample 3 than the measurement probe 22 is. Make it protrude.

  In this state, coarse movement is performed by the coarse movement mechanism 5 to reduce the distance between the coarse movement probe 21 and the sample 3, and the physical force such as the atomic force, magnetic force, viscoelasticity, etc. received by the probe 1 from the surface of the sample 3 is performed. When the deformation of the coarse movement cantilever 23 is detected from a change in the resistance value of a piezo element (not shown) provided in the coarse movement cantilever 23 and the deformation reaches a predetermined value, the coarse movement mechanism 5 is While stopping, the Z-axis of the fine movement mechanism 4 for relatively moving the sample 3 and the coarse movement probe 21 configured on the sample side is controlled to maintain the surface distance between the coarse movement probe 21 and the sample 3. While controlling the Z axis of the mechanism 4, the coarse movement mechanism 5 is driven to adjust the displacement amount of the Z axis of the fine movement mechanism 4, thereby positioning the coarse movement probe 21 and the surface of the sample 3. Next, the fine movement mechanism 4 provided on the sample side is moved in the Z-axis direction to once increase the distance between the sample 3 and the coarse movement probe 21. Next, the current is stopped in the thermal resistor 40 of the measurement cantilever 24 and the current is passed through the thermal resistor 40 of the coarse movement cantilever 23 so that the measurement probe 22 protrudes from the coarse movement probe 21. In this state, the Z-axis of the fine movement mechanism 3 is operated to further reduce the distance between the probe 1 and the surface of the sample 3, and the deformation of the measurement cantilever 24 is deformed by a piezoelectric element (not shown) provided on the measurement cantilever 24. 1), when the deformation reaches a predetermined value, control is performed so that the deformation value becomes constant, and the fine movement mechanism 4 is measured while scanning the sample surface. To visually image the shape and physical properties of the sample surface.

  In the present embodiment, the cantilever is warped away from the sample by flowing an electric current. However, the cantilever may be warped in a direction approaching the sample by flowing an electric current. Alternatively, a difference in the attitude of the probe may be generated by supplying a current to both cantilevers and controlling the amount of the current.

  As described above, the cantilever conversion means is configured by utilizing the fact that the current flows through the thermal resistor and the cantilever is warped by heat.

  Next, a fourth embodiment of the probe microscope apparatus according to the present invention will be described with reference to FIGS.

  Note that in the fourth embodiment, identical symbols are assigned to configurations identical to those in the first, second, and third embodiments and descriptions thereof are omitted.

  FIG. 8 is a configuration diagram of a cantilever of a probe microscope according to the fourth embodiment of the present invention.

  In this embodiment, the self-detecting cantilever shown in the third embodiment has a shape in which the cantilever with the coarse movement probe 21 and the cantilever with the measurement probe 22 have different resonance frequencies.

As shown in FIG. 9, the cantilevers 23 and 24 are equivalent to those described in the third embodiment via the cantilever holder 13 in which a vibrating piezoelectric plate 32 composed of a piezoelectric element for vibrating the cantilevers 23 and 24 is configured. Attach to the probe microscope.
During coarse movement, the vibration piezoelectric plate 32 is driven at the resonance frequency of the cantilever 23 in which the coarse movement probe 21 is configured to vibrate the coarse movement cantilever 23, and the coarse movement probe 21 side is moved toward the measurement probe 22. Coarse movement is performed as in the third embodiment in a state where the amplitude is larger than that of the first side. After the coarse movement is completed, the Z axis of the fine movement mechanism 4 is operated to once increase the distance between the sample 3 and the coarse movement probe 21. Next, the vibration piezoelectric plate 32 is driven at the resonance frequency of the measurement cantilever 24 having the measurement probe 22 to vibrate the cantilever so that the measurement probe 22 side has a larger amplitude than the coarse movement probe 21 side. In this state, the Z-axis is operated to position the measurement probe 22 on the sample surface so that measurement is possible.

  In this way, the control voltage of the vibration piezoelectric plate 32 is changed to each resonance frequency, thereby providing the cantilever conversion means.

  In each embodiment, an example is shown in which the sample side is scanned three-dimensionally. However, a fine movement mechanism 4 is provided on the probe side, or a mechanism (stage or the like) for aligning the sample and the probe in the plane (two-dimensional). ) May be provided on the probe side or the sample side.

  In each embodiment, the case of one coarse movement cantilever is used, but a plurality of coarse movement cantilevers may be provided. Thereby, the influence of the inclination of the sample surface can be reduced, and the possibility of breakage of the measurement cantilever can be further reduced.

It is a block diagram which shows the outline | summary of the cantilever of the probe microscope of 1st embodiment of this invention. It is a state figure showing positioning of a cantilever in a probe microscope of a first embodiment of the present invention. It is a block diagram which shows the outline | summary of the cantilever holder part of the probe microscope of 1st embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever of the probe microscope of 2nd embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever holder part of the probe microscope of 2nd embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever of the probe microscope of 3rd embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever holder part of the probe microscope of 3rd embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever of the probe microscope of 4th embodiment of this invention. It is a block diagram which shows the outline | summary of the cantilever holder part of the probe microscope of 4th embodiment of this invention. It is a block diagram which shows the schematic system of a probe microscope. It is the block diagram which showed the general cantilever shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe 2 Cantilever 3 Sample 4 Fine movement mechanism 5 Coarse movement mechanism 6 Displacement detection system 7 Laser 8 Photo detector 9 Amplifier 10 Z-axis control feedback circuit 11 XY drive circuit 12 Computer and control system 13 Cantilever holder 21 Coarse movement probe 22 Measuring probe 23 Coarse cantilever 24 Measuring cantilever 25 Cantilever substrate 26 Inclined block 27 Fixed spring 28 Hole in cantilever holder 29 Inclined portion 30 Handle 31 Inclining mechanism (cantilever converting means)
32 Piezoelectric plate for vibration 40 Thermal resistor (cantilever conversion means)
41 Dummy resistor 42 Cantilever substrate 43 Substrate 44 Mold part 45 Self-detection signal wiring 46 Contact electrode 47 Cantilever mount 48 Tilt mechanism wiring 49 Diaphragm wiring 50 Wiring

Claims (14)

A cantilever having a probe at the tip, and a coarse movement mechanism and a fine movement mechanism for controlling the distance between the cantilever and the sample,
A probe microscope that measures the shape information or physical information of the sample surface by bringing the probe close to or in contact with the sample surface,
The cantilever comprises a measurement cantilever having a measurement probe and a coarse movement cantilever having at least one coarse movement probe,
A cantilever conversion means for controlling a distance between the measurement probe and the coarse movement probe with respect to the sample surface;
With the coarse movement probe protruding so as to approach the sample surface from the measurement probe, the coarse movement probe of the coarse movement cantilever approaches or contacts the sample surface,
The measurement tip is projected by the cantilever conversion means so that the measurement probe approaches the sample surface from the coarse movement probe, and then the sample surface is measured by the measurement probe of the measurement cantilever. Probe microscope. The probe microscope according to claim 1,
After the coarse movement probe of the coarse movement cantilever approaches or contacts the sample surface,
After moving the coarse movement cantilever away from the sample surface with the coarse movement mechanism or the fine movement mechanism,
A probe microscope characterized in that the cantilever conversion means causes the measurement probe to protrude closer to the sample surface than the coarse movement probe. The probe microscope according to claim 1,
Including a fine movement mechanism for relatively moving the cantilever and the sample;
The cantilever conversion means causes the measurement probe to protrude from the coarse movement probe so as to approach the sample surface, and then measures the sample surface with the measurement probe while scanning with the fine movement mechanism. A probe microscope characterized by that. The probe microscope according to claim 1,
The cantilever converting means is located on the cantilever substrate provided with the measurement cantilever and the coarse motion cantilever, with respect to the width direction of the cantilever substrate perpendicular to the longitudinal direction of the measurement cantilever and the coarse motion cantilever. A probe microscope characterized by comprising a piezoelectric body provided to be shifted outward. The probe microscope according to claim 4, wherein
A probe microscope characterized in that the cantilever conversion means adds a displacement magnifying mechanism to the piezoelectric body. The probe microscope according to claim 1,
The probe microscope, wherein the cantilever conversion means is the measurement cantilever and the coarse movement cantilever having different resonance frequencies. The probe microscope according to any one of claims 1 to 6,
The probe microscope characterized in that the measurement cantilever and the coarse movement cantilever are self-detecting cantilevers. The probe microscope according to claim 1,
The cantilever conversion means includes a thermal resistor on at least one of the measurement cantilever and the coarse movement cantilever;
A probe microscope, wherein an electric current is passed through the thermal resistor to warp the measurement cantilever or the coarse movement cantilever. The probe microscope according to claim 1,
A probe microscope characterized in that the tip radius of the coarse probe is larger than the tip radius of the measuring probe. A probe microscope measuring method for measuring shape information or physical information of the sample surface by bringing a probe close to or in contact with the sample surface,
Bringing at least one coarse probe provided at the tip of at least one coarse cantilever to approach or contact the sample surface;
A cantilever converting means for controlling a distance relationship between the measurement probe and the coarse movement probe with respect to the sample surface, and the measurement probe provided at the tip of the measurement cantilever is more than the coarse movement probe. Projecting to approach
Measuring the surface of the sample with a measuring probe of the measuring cantilever. In the measuring method of the probe microscope according to claim 10,
After the coarse movement probe of the coarse movement cantilever approaches or contacts the sample surface,
A measurement method of a probe microscope in which a step of moving the coarse movement cantilever in a direction away from a sample surface by the coarse movement mechanism or the fine movement mechanism is added. In the measuring method of the probe microscope according to claim 10,
After the step of causing the measurement probe to protrude closer to the sample surface than the coarse movement probe by the cantilever conversion means, a fine movement mechanism for moving the cantilever and the sample relative to each other for the measurement A probe microscope measurement method for measuring the sample surface while scanning with a probe. In the measuring method of the probe microscope according to claim 10,
The step of projecting the measurement probe provided at the tip of the measurement cantilever by the cantilever conversion means so as to approach the sample surface from the coarse movement probe is provided with the measurement cantilever and the coarse movement cantilever. A piezoelectric body is used on the cantilever substrate provided so as to be shifted outward from the center with respect to the width direction of the cantilever substrate perpendicular to the longitudinal direction of the measurement cantilever or the coarse motion cantilever. Probe microscope measurement method. In the measuring method of the probe microscope according to claim 10,
Using the measurement cantilever and the coarse movement cantilever having different resonance frequencies, and the vibration piezoelectric plate for vibrating the measurement cantilever and the coarse movement cantilever,
In the step of approaching or contacting the coarse movement probe provided at the tip of the coarse movement cantilever with the sample surface, the vibration piezoelectric plate vibrates at the resonance frequency of the coarse movement cantilever,
In the step of causing the measurement probe provided at the tip of the measurement cantilever to protrude closer to the sample surface than the coarse movement probe, the vibration cantilever is vibrated at the resonance frequency of the measurement cantilever. A measuring method using a probe microscope.

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