JP2006329704A - Scanning probe microscope - Google Patents

Abstract

There is provided a scanning probe microscope capable of increasing a scanning range and observing a sample with high accuracy.
A probe, a position detector 2 for detecting the position of the probe 1, a displacement mechanism 3 for displacing the probe 1 in a direction orthogonal to a sample S, and a displacement mechanism 3 on the Z axis. The scanning probe microscope includes a scanning mechanism 4 that moves in a direction perpendicular to the X axis and a scanning mechanism 5 that moves the displacement mechanism 3 in a Y axis direction perpendicular to the Z axis and the X axis. . The displacement mechanism 3 is composed of a piezoelectric element 10 that expands and contracts in the Z-axis direction. The scanning mechanism 4 includes a piezoelectric element 11 that expands and contracts in the Y-axis direction, and a link mechanism 12 that enlarges and converts the expansion and contraction of the piezoelectric element 11 to expand and contract in the X-axis direction. The scanning mechanism 5 includes a piezoelectric element 13 that expands and contracts in the X-axis direction, and a link mechanism 14 that enlarges and converts the expansion and contraction of the piezoelectric element 13 to expand and contract in the Y-axis direction.
[Selection] Figure 1

Description

  The present invention relates to a scanning probe microscope.

  In recent years, the wave of miniaturization accompanying rapid advancement of nanotechnology has spread to all fields and industries, and the necessity to use fine measurement tools is increasing. Under such circumstances, an atomic force microscope (see, for example, Patent Document 1), which is a scanning probe microscope that has been used for analyzing an atomic arrangement structure or the like, has attracted attention. The scanning probe microscope has a measurement resolution of atomic order (nanometer or less) and is being applied to various fields including surface shape measurement. Depending on the physical quantity used for detection, there are a scanning tunneling microscope (STM), an atomic force microscope (AFM), a magnetic force microscope (MFM), and the like.

  As shown in FIG. 5, the atomic force microscope includes a frame 71 having a sample stage 70, a probe approach mechanism 72 provided on the frame 71, and an XYZ fine movement mechanism attached to the probe approach mechanism 72. 73, and the XYZ fine movement mechanism 73 is provided with a cantilever 75 having a probe 74 at the tip. A displacement detector 76 that detects the amount of displacement of the cantilever 75 is disposed in the vicinity of the cantilever 75. In this case, the probe approach mechanism 72 is for making the probe 74 approach the sample 77 on the sample stage 70 before performing the measurement, and the XYZ fine movement mechanism 73 is orthogonal to the sample 77. It is constituted by a cylindrical actuator using a piezoelectric element that expands and contracts in the Z-axis direction, which is the direction, and in the X-axis direction and the Y-axis direction that are orthogonal to the Z-axis direction. That is, the actuator can be expanded and contracted in the Z-axis direction by applying a voltage of the Z-direction piezoelectric element, and the actuator can be expanded and contracted in the X-axis direction by applying a voltage to the X-direction piezoelectric element. The actuator can be expanded and contracted in the Y-axis direction by applying a voltage to the Y-direction piezoelectric element.

  The displacement detector 76 includes a light source that emits laser light and a photodetector that receives the laser light. The laser light from the light source is reflected by the reflecting surface on the back surface of the cantilever 75 and is incident on the photodetector, whereby the change in deflection of the cantilever 75 can be known.

  That is, when the probe 74 is brought closer to the sample 77, the attractive force is first exerted by van der Waals force or the like, and the probe 74 is attracted. As it gets closer, repulsive force begins to work between the electron cloud at the tip of the probe 74 and the sample. As the distance between the two decreases, the attractive force and the repulsive force eventually become parallel, and the repulsive force becomes dominant. The atomic force is detected by the deflection of the cantilever 75. When the laser beam is applied to the back surface of the tip of the cantilever 75 and the reflected light is incident on the displacement detector 76, and the received light balance of the laser spot is detected using this as an electrical signal, the change in deflection of the cantilever 75 in the vertical and horizontal directions is known. be able to.

When the probe 74 is in contact with the sample 77 and secondarily scanned in the X-axis direction and the Y-axis direction, the cantilever 75 tries to bend along the shape of the sample 77. This change in deflection is fed back to the Z-direction piezoelectric element so that it always follows a constant deflection amount, and the expansion / contraction change amount of the Z-direction piezoelectric element is captured by the control unit (computer). Since the acquired data has a secondary array and each has an expansion / contraction change amount, the surface structure of the sample 77 can be imaged as a three-dimensional shape. That is, since the displacement feedback amount is imaged, the height information of the sample shape can be acquired in units of length.
JP 2000-266770 A

  As described above, piezoelectric elements are used for scanning in the X-axis direction and the Y-axis direction, respectively, but the scanning range is limited due to the shape of the piezoelectric elements. Further, when the scanning range is expanded to the limit, problems occur in accuracy and rigidity. That is, in the conventional scanning probe microscope, scanning in the X-axis direction and the Y-axis direction is limited to about 100 microns. However, in recent years, large liquid crystal panels and the like have appeared, and one pixel has become larger. For this reason, in order to cope with such a thing, the thing with a wide scanning range has come to be calculated | required.

  As described above, if the XYZ fine movement mechanism 73 is a cylindrical actuator using a piezoelectric element, there are the following problems. That is, it is necessary to correct non-linearity due to hysteresis, and since the drive voltage and the scanning range are not proportional and the scanning range changes depending on the scanning speed, it is necessary to correct these. Furthermore, there are problems in image distortion when scanned by rotating to an arbitrary angle, image distortion and displacement due to creep (history) characteristics of the piezoelectric element, and positional accuracy during zoom scanning. In addition, because of the above correction, the correction calculation formula in the software is complicated and there is a limit to the improvement. The procedure for shipping and periodic calibration is difficult and the processing time is long.

  The present invention has been made to solve the above-described conventional drawbacks, and an object of the present invention is to provide a scanning probe microscope capable of increasing the scanning range and observing a sample with high accuracy. It is in.

  Accordingly, the scanning probe microscope of claim 1 includes a probe 1, a position detector 2 that detects the position of the probe 1, and the probe 1 is displaced in the Z-axis direction perpendicular to the sample S. The Z-axis direction displacement mechanism 3 to be moved, the X-axis direction scanning mechanism 4 to move the Z-axis direction displacement mechanism 3 in the X-axis direction perpendicular to the Z-axis, and the Z-axis direction displacement mechanism 3 to the Z-axis And a scanning probe microscope having a Y-axis direction scanning mechanism 5 that moves in the Y-axis direction orthogonal to the X-axis, the Z-axis direction displacement mechanism 3 extending and contracting in the Z-axis direction And the X-axis direction scanning mechanism 4 includes a Y-direction piezoelectric element 11 that expands and contracts in the Y-axis direction and the Y-axis direction expansion and contraction of the Y-direction piezoelectric element 11 in the X-axis. The X direction conversion link mechanism 12 that expands and converts the direction to expansion and contraction The Y-axis direction scanning mechanism 5 includes an X-direction piezoelectric element 13 that expands and contracts in the X-axis direction, and a Y-direction conversion link that expands and converts the X-axis direction expansion and contraction of the X-direction piezoelectric element 13 into the Y-axis direction expansion and contraction. It is characterized by comprising the mechanism 14.

  In the scanning probe microscope according to the second aspect, each of the conversion link mechanisms 12 and 14 is disposed on both ends of the piezoelectric elements 11 and 13 and is moved in the longitudinal direction of the piezoelectric element in accordance with the displacement of the piezoelectric elements 11 and 13. The end members 15, 16, 31, 32 that are displaced and the end members 15, 16, 31, 32 on both ends are connected to the end hinges 21, 22, 23, 24, 37, 38, 39, 40. The connecting members 19, 20 are arranged so that the intermediate pinge portions 25, 26, 41, 42 are arranged inside or outside the straight lines A, B connecting the end members 15, 16, 31, 32 before voltage application. , 35, and 36, and by applying a voltage, the displacement of the piezoelectric elements 11 and 13 of the intermediate portions 17, 18, 33, and 34 of the connecting members 19, 20, 35, and 36 in the direction orthogonal to the longitudinal direction of the piezoelectric elements It is characterized by converting to displacement There.

  The scanning probe microscope according to a third aspect of the present invention includes a position detector 2 such that the position detector 2 moves integrally with the movement of the Z-direction piezoelectric element 10 by the X-axis direction scanning mechanism 4 and the Y-axis direction scanning mechanism 5. Is arranged on the Z-direction piezoelectric element 10 side.

  In the scanning probe microscope of claim 4, the base end of the cantilever 6 having the probe 1 attached to the tip is connected to the lower end of the Z-direction piezoelectric element 10, and the laser beam is sent to the center line O of the Z-direction piezoelectric element 10. Is provided above the Z-direction piezoelectric element 10 so that the laser reflected light reflected from the back surface of the cantilever 6 enters the position detector 2.

  According to the scanning probe microscope of claim 1, the X-axis direction scanning mechanism is expanded to expand and contract in the Y-axis direction, and the Y-direction piezoelectric element that expands and contracts in the Y-axis direction. Since the X-direction conversion link mechanism for conversion is used, the scanning range in the X-axis direction can be made larger than the conventional one that is determined only by expansion and contraction of the piezoelectric element. Further, the Y-axis direction scanning mechanism includes an X-direction piezoelectric element that expands and contracts in the X-axis direction, and a Y-direction conversion link mechanism that expands and converts the X-axis direction expansion and contraction of the X-direction piezoelectric element into the Y-axis direction expansion and contraction. Since it is configured, the scanning range in the Y-axis direction can be made larger than the conventional range determined only by the expansion and contraction of the piezoelectric element. In this way, the scanning range in the X-axis direction and the Y-axis direction can be increased, and the pixel size of a large-sized liquid crystal panel that has become widespread in recent years can be accommodated. In addition, since the Z-axis direction displacement mechanism is composed of the Z-direction piezoelectric element that expands and contracts in the Z-axis direction, a stable image can be obtained. Further, problems such as the XY orthogonality and the bending characteristics in the Z direction are eliminated, the correction on the software is reduced, a complicated correction formula is not required, and the program can be simplified. Furthermore, since the X-axis direction scanning mechanism and the Y-axis direction scanning mechanism can each be constituted by a piezoelectric element and a link mechanism, the mechanism can be simplified and the assembly adjustment can be simplified. The mounting accuracy is improved, the scanning center axis and the optical axis accuracy (the accuracy of the optical axis of the laser beam from the laser output unit and the reflected beam from the cantilever) are improved, and the observation accuracy can be improved.

  According to the scanning probe microscope of the second aspect, since the displacement of the piezoelectric element is converted into the displacement of the intermediate portion of the connecting member in the direction orthogonal to the longitudinal direction of the piezoelectric element, The scanning range can be surely made larger than that of the conventional one, and the structure of the link mechanism is simple, the overall size is not increased, and the scanning accuracy is good.

  According to the scanning probe microscope of the third aspect, since the position detector moves integrally with the movement of the Z-direction piezoelectric element by the X-axis direction scanning mechanism and the Y-axis direction scanning mechanism, stable observation can be performed. The observation accuracy can be improved. In particular, the X-axis direction scanning mechanism is composed of a Y-direction piezoelectric element and an X-direction conversion link mechanism, and the Y-axis direction scanning mechanism is composed of an X-direction piezoelectric element and a Y-direction conversion link mechanism. Each scanning mechanism is excellent in rigidity, can stably move the Z-direction piezoelectric element and the position detector integrally, and can always perform highly accurate observation stably.

  According to the scanning probe microscope of the fourth aspect, since the laser output unit for irradiating the Z direction piezoelectric element with the laser beam along the center line is provided above the Z direction piezoelectric element, the laser beam is transmitted in the Z direction piezoelectric element. As a result, the laser reflected light reflected from the back surface of the cantilever can be incident on the position detector with high accuracy, and a further improvement in observation accuracy can be achieved.

  Next, specific embodiments of the scanning probe microscope of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall simplified view of a scanning probe microscope. The scanning probe microscope includes a probe 1, a position detector 2 for detecting the position of the probe 1, and the probe 1 with respect to a sample S. Z-axis direction displacement mechanism 3 for displacing the Z-axis direction displacement mechanism 3 in the Z-axis direction, and an X-axis direction scanning mechanism for moving the Z-axis direction displacement mechanism 3 in the X-axis direction perpendicular to the Z-axis (hereinafter, 4) and a Y-axis direction scanning mechanism (hereinafter referred to as Y-fine movement) that moves the Z-axis direction displacement mechanism 3 in the Y-axis direction perpendicular to the Z-axis and the X-axis. 5) (sometimes called a stage).

  The Z-axis direction displacement mechanism 3 includes a Z-direction piezoelectric element 10 that expands and contracts in the Z-axis direction by applying a voltage. A cantilever 6 is attached to the lower end of the Z-axis direction displacement mechanism 3, and a probe 1 is provided at the tip of the cantilever 6. ing. The cantilever 6 is made of a flat substrate, and its proximal end is attached to the Z-direction piezoelectric element 10 so as to form a predetermined angle with respect to the Z-axis. Then, laser light is emitted from the light source (laser output unit) 7 toward the back surface of the cantilever 6 along the center line O of the Z-direction piezoelectric element 10. For this reason, the position detector 2 includes a photodiode into which the reflected light reflected from the back surface of the cantilever 6 enters. In this photodiode, it is converted into an electric signal (position detection signal), and this position detection signal is input to the adder 8. The photodiode is divided into a plurality of, for example, four.

  In the adder 8, the preset target setting value is compared with the position inspection signal, and a deviation signal is output to the control unit 9. The control unit 9 can control the voltage applied to the Z-direction piezoelectric element 10 based on the deviation signal, and can keep the distance between the probe 1 and the sample S constant.

  As shown in FIG. 2, the X fine movement stage 4 expands and converts the Y-direction piezoelectric element 11 that expands and contracts in the Y-axis direction and the Y-axis direction expansion and contraction of the Y-direction piezoelectric element 11 into the X-axis direction expansion and contraction. As shown in FIG. 3, the X-direction converting link mechanism 12 and the Y-fine movement stage 5 are expanded and contracted in the X-axis direction, and the X-axis of the X-direction piezoelectric element 13 is X-axis. It is composed of a Y-direction changing link mechanism 14 for enlarging and converting the direction expansion and contraction to the Y-axis direction expansion and contraction.

  The X-direction converting link mechanism 12 is disposed on both end sides of the Y-direction piezoelectric element 11, and has end members 15 and 16 that are displaced in the longitudinal direction of the piezoelectric element in accordance with the displacement of the Y-direction piezoelectric element 11. Side end members 15 and 16 are connected, and intermediate portions 17 and 18 are provided with connecting members 19 and 20 arranged on the inner side of straight lines A and A connecting end members 15 and 16 before voltage application. . The connecting members 19 and 20 include end hinge portions 21 and 22 on one end member 15 side, end hinge portions 23 and 24 on the other end member 16 side, and intermediate hinge portions of the intermediate portions 17 and 18. 25, 26 and links 27, 28, 29, 30 connecting the respective hinge portions 21, 22, 23, 24, 25, 26. That is, one connecting member 19 has two links 27 and 28, and the other connecting member 20 has two links 29 and 30, and the links of the X-direction converting link mechanism 12 are total. There are four.

  The Y-direction converting link mechanism 14 is disposed on both ends of the X-direction piezoelectric element 13 and is displaced in the longitudinal direction of the piezoelectric element with the displacement of the X-direction piezoelectric element 13. Side end members 31, 32 are connected, and intermediate portions 33, 34 are provided with connecting members 35, 36 arranged on the inner side of straight lines B, B connecting the end members 31, 32 before voltage application. . The connecting members 35, 36 include end hinge portions 37, 38 on one end member 31 side, end hinge portions 39, 40 on the other end member 32 side, and intermediate hinge portions of the intermediate portions 33, 34. 41, 42 and links 43, 44, 45, 46 for connecting the hinge portions 37, 38, 39, 40, 41, 42 to each other. That is, one connecting member 35 has two links 43 and 44, and the other connecting member 36 has two links 45 and 46, and the links of the Y-direction changing link mechanism 14 are total. There are four.

  For this reason, in the X-direction converting link mechanism 12, when a voltage is applied to the Y-direction piezoelectric element 11 and the Y-direction piezoelectric element 11 extends in the longitudinal direction (Y-axis direction), the connecting member 19 accompanies the extension. , 20 are displaced in the direction away from the Y-direction piezoelectric element 11 (X-axis direction). In addition, in the Y-direction converting link mechanism 14, when a voltage is applied to the X-direction piezoelectric element 13 and the X-direction piezoelectric element 13 extends in the longitudinal direction (X-axis direction), the connecting member 35, The intermediate portions 33 and 34 of 36 are displaced in a direction away from the X-direction piezoelectric element 13 (Y-axis direction).

  In the X fine movement stage 4, as shown in FIG. 4, when the length of the links 27 and 28 is L and the angle formed by the straight line A and the link 27 (28) is θ, the Y-direction piezoelectric element 11 is only a. If the angle formed by the straight line A and the link 27 becomes θ1, the a can be obtained as shown in the following equation 1, and the displacement amount of the intermediate portion 17 in the direction orthogonal to the longitudinal direction of the piezoelectric element can be calculated. If b is assumed, b can be obtained as in the following formula 2.

  At this time, when the Y-direction piezoelectric element 11 extends by the same amount, the links 27 and 28 swing more greatly as the angle α formed by the links 27 and 28 before the voltage is applied is smaller. The displacement amount b in the direction orthogonal to the piezoelectric element longitudinal direction can be increased. Similarly, on the other links 29 and 30 side, the intermediate portion 18 is displaced in a direction perpendicular to the longitudinal direction of the piezoelectric element, and the displacement amount is the same as the links 27 and 28 shown in FIG. For this reason, the displacement as a whole in the direction orthogonal to the longitudinal direction of the piezoelectric element with respect to the longitudinal extension a of the Y-direction piezoelectric element 11 is 2b. Thereby, in the X fine movement stage 4, the expansion and contraction in the Y-axis direction of the Y-direction piezoelectric element 11 can be enlarged and converted to the expansion and contraction in the X-axis direction. Then, the Z-direction piezoelectric element 10 can be moved in the X-axis direction with this increased displacement.

  Further, since the Y fine movement stage 5 has the same structure as the X fine movement stage 4, when the X direction piezoelectric element 13 extends by a in the longitudinal direction (X axis direction), the direction orthogonal to the longitudinal direction of the piezoelectric element. It is displaced by 2b in the (Y-axis direction), and the expansion and contraction of the X-direction piezoelectric element 13 in the X-axis direction can be enlarged and converted to the expansion and contraction in the Y-axis direction. Then, the Z-direction piezoelectric element 10 can be moved in the Y-axis direction with the increased displacement.

  By the way, the X fine movement stage 4 and the Y fine movement stage 5 are connected by a connection mechanism (not shown), and when a voltage is applied to the Y direction piezoelectric element 11 of the X fine movement stage 4, the Z direction piezoelectric element 10 is moved along the X axis direction. If a voltage is applied to the X-direction piezoelectric element 13 of the Y fine movement stage 5, the Z-direction piezoelectric element 10 can be moved along the Y-axis direction together with the X fine movement stage 4.

  The X fine movement stage 4 and the Y fine movement stage 5 are attached to a head frame (not shown), and a Z direction piezoelectric element 10 and a position detector 2 are attached to the X fine movement stage 4 via a laser output unit (light source) 7. . For this reason, the position detector 2 integrally moves in the X-axis direction along with the movement of the Z-direction piezoelectric element 10 in the X-axis direction by the X fine movement stage 4, and the Y-direction of the Z-direction piezoelectric element 10 by the Y fine movement stage 5. The position detector 2 moves in the Y-axis direction as a unit.

  A piezoelectric element driving circuit 52 is connected to each fine movement stage 4, 5, and a scanning signal generating unit 53 is connected to the piezoelectric element driving circuit 52. The scanning signal generator 53 is connected to a signal processor 55 connected to the controller 9 and the display device 54. Here, the scanning signal generation unit 53 transmits a signal to the piezoelectric element driving circuit 52 by a signal from the signal processing unit 55, and the Y direction piezoelectric elements 11 and Y of the X fine movement stage 4 are transmitted from the piezoelectric element driving circuit 52. A voltage is applied to the X-direction piezoelectric element 13 of the fine movement stage 5. Incidentally, the display device 54 has a monitor screen, and displays an image of the sample S observed based on the data obtained from the signal processing unit 55 on the monitor screen.

  Next, an observation method of the sample S using the scanning probe microscope configured as described above will be described. First, the probe 1 is moved closer to the observed portion of the sample S using the Z-axis direction displacement mechanism 3. The interatomic force generated by this is captured as a shake due to the deflection of the cantilever 6. That is, a laser beam is applied to the back surface of the tip of the cantilever 6 and the reflected light is incident on the position detector 2. This is used as an electrical signal to detect the light reception balance of the laser spot, and to detect a change in deflection of the cantilever 6 in the vertical and horizontal directions.

  Then, with the probe 1 in contact with the sample S, the X fine movement stage 4 and / or the Y fine movement stage 5 are driven via the piezoelectric element drive circuit 52 based on the signal from the scanning signal generator 53. Then, the Z-axis direction displacement mechanism 3 is scanned (moved) in the X-axis direction and / or the Y-axis direction. Thereby, the cantilever 6 tries to bend along the shape of the sample S. This change in deflection is fed back to the Z-direction piezoelectric element 10 of the Z-axis direction displacement mechanism 3 so that a constant deflection amount is always maintained. At this time, the control unit 9 captures the expansion / contraction change amount of the Z-direction piezoelectric element 10. Although this captured data is a two-dimensional array, each has an expansion / contraction change amount, so that the surface structure of the sample S can be imaged as a three-dimensional shape, and a signal from the control unit 9 is obtained. The surface structure of the sample S can be displayed on the display device 54 by processing in the signal processing unit 55. For this reason, since the displacement feedback amount is imaged, the height information of the sample shape can be acquired in units of length.

  In the scanning probe microscope, the X-axis direction scanning mechanism 4 expands and converts the Y-direction piezoelectric element 11 that expands and contracts in the Y-axis direction and the Y-axis direction expansion and contraction of the Y-direction piezoelectric element 11 into the X-axis direction expansion and contraction. Since the X-direction converting link mechanism 12 is used, the scanning range in the X-axis direction can be made larger than the conventional one that is determined only by the expansion and contraction of the piezoelectric element. The Y-axis direction scanning mechanism 5 includes an X-direction piezoelectric element 13 that expands and contracts in the X-axis direction, and a Y-direction conversion link that expands and converts the X-axis direction expansion and contraction of the X-direction piezoelectric element 13 into the Y-axis direction expansion and contraction. Since it is configured with the mechanism 14, the scanning range in the Y-axis direction can be made larger than that of the conventional one that is determined only by the expansion and contraction of the piezoelectric element. For example, a scanning range of about 500 μm to 700 μm can be taken. In this way, the scanning range in the X-axis direction and the Y-axis direction can be increased, and the pixel size of a large-sized liquid crystal panel that has become widespread in recent years can be accommodated. Moreover, since the Z-axis direction displacement mechanism 3 is composed of the Z-direction piezoelectric element 10 that expands and contracts in the Z-axis direction, a stable image can be obtained. Further, problems such as the XY orthogonality and the bending characteristics in the Z direction are eliminated, the correction on the software is reduced, a complicated correction formula is not required, and the program can be simplified. Furthermore, since the X-axis direction scanning mechanism 4 and the Y-axis direction scanning mechanism 5 can be composed of the piezoelectric elements 11 and 13 and the link mechanisms 12 and 14, respectively, the mechanism can be simplified. Assembling adjustment is simplified, the mounting accuracy is improved, the scanning center axis and the optical axis accuracy (the accuracy of the optical axis of the laser beam from the laser output unit 7 and the reflected beam from the cantilever 6) are improved, and the observation accuracy Improvement can be achieved.

  Since the displacement of the piezoelectric elements 11 and 13 is converted into the displacement of the intermediate portions 17, 18, 33 and 34 of the connecting members 19, 20, 35 and 36 in the direction orthogonal to the longitudinal direction of the piezoelectric element, the X-axis direction In addition, the scanning range in the Y-axis direction can be surely increased as compared with the conventional one, and the structures of the link mechanisms 12 and 14 are simple, and the overall size is not increased and the scanning accuracy is good. Furthermore, since the position detector 2 moves together with the movement of the Z-direction piezoelectric element 10 by the X-axis direction scanning mechanism 4 and the Y-axis direction scanning mechanism 5, stable observation can be performed and the observation accuracy is improved. be able to. In particular, the X-axis direction scanning mechanism 4 includes a Y-direction piezoelectric element 11 and an X-direction conversion link mechanism 12, and the Y-axis direction scanning mechanism 5 includes an X-direction piezoelectric element 13 and a Y-direction conversion link mechanism 14. Therefore, each of these scanning mechanisms 4 and 5 is excellent in rigidity, can stably perform the integral movement of the Z-direction piezoelectric element 10 and the position detector 2, and can always stably perform high-precision observation. Can be done.

  Further, since the laser output unit 7 for irradiating the Z-direction piezoelectric element 10 along the center line O is provided above the Z-direction piezoelectric element 10, the laser light passes through the Z-direction piezoelectric element 10. Thus, the overall size can be reduced, and the laser reflected light reflected from the back surface of the cantilever 6 can be incident on the position detection 2 with high accuracy, thereby further improving the observation accuracy.

  Further, the force acting on the probe 1 from the surface of the sample S also acts in the lateral direction. Therefore, when the lateral twist of the cantilever 6 is detected, an image exerted by the frictional force along with the scanning can be captured. This is called LFM (friction force or horizontal microscope), and can detect a surface structure that cannot be obtained by unevenness information, and can detect a difference in material composition. Therefore, it is preferable to measure the LFM image simultaneously with the AFM (atomic force microscope) measurement (actually immediately after the AFM measurement). As a result, both images can be compared, and observation with higher accuracy becomes possible.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention. For example, in the above embodiment, the displacement in the Z-axis direction is fed back, but the detection signal, that is, the shake signal of the cantilever 6 may be imaged as it is without applying the feedback. In addition, as the link mechanisms 12 and 14 of the scanning mechanisms 4 and 5, the intermediate portions 17, 18, 33, and 34 are arranged inside the straight lines A and B, but from the straight lines A and B, May be arranged outside. In this case, the X fine movement stage 4 is arranged outside the straight line A, and the Y fine movement stage 5 is arranged inside the straight line B. Conversely, the X fine movement stage 4 is arranged along the straight line A. In addition, the Y fine movement stage 5 can be arranged outside the straight line B. That is, the expansion and contraction in the longitudinal direction of the piezoelectric elements 11 and 13 is expanded and converted in a direction orthogonal to the longitudinal direction, and the Z-direction piezoelectric element 10 is moved in the X-axis direction (Y-axis direction) with the expanded displacement. ) As long as it can be moved to. In the above embodiment, the Y fine movement stage 5 is arranged on the X fine movement stage 4, but the X fine movement stage 4 may be arranged on the Y fine movement stage 5. By the way, the sample S to be observed is not limited to the liquid crystal panel, and various products can be used. The film surface can be measured in an ultra-fine field of view of several μm, or about 0.1 mm to 0.5 mm. Shape measurement and the like can be accurately performed with this scanning probe microscope.

It is a simplified block diagram which shows embodiment of the scanning probe microscope of this invention. It is a simplified diagram of the X-axis direction scanning mechanism of the scanning probe microscope. It is a simplified diagram of the Y-axis direction scanning mechanism of the scanning probe microscope. It is a simplified diagram explaining the displacement of the scanning mechanism of the scanning probe microscope. It is a simplified diagram of a conventional scanning probe microscope.

Explanation of symbols

  1 .... probe 2 .... position detector 3 .... Z axis direction displacement mechanism 4 .... X axis direction scanning mechanism (X fine movement stage) 5 .... Y axis direction scanning mechanism (Y fine movement stage), 10 .... Z direction piezoelectric element, 11 .... Y direction piezoelectric element, 12 .... X direction conversion link mechanism, 13 .... X direction piezoelectric element, 14 .... Y direction conversion link mechanism, 15, 16, ... end Part member, 17, 18 ... Intermediate part, 19, 20 ... Connecting member 31, 32 ... End member, 33, 34 ... Intermediate part, 35, 36 ... Connecting member, O ... Center line, S ・ ・ Sample

Claims (4)

  A probe (1), a position detector (2) for detecting the position of the probe (1), and the probe (1) are displaced in the Z-axis direction perpendicular to the sample (S). A Z-axis direction displacement mechanism (3), an X-axis direction scanning mechanism (4) for moving the Z-axis direction displacement mechanism (3) in the X-axis direction perpendicular to the Z-axis, and a Z-axis direction displacement mechanism A scanning probe microscope provided with a Y-axis direction scanning mechanism (5) for moving (3) in the Y-axis direction perpendicular to the Z-axis and the X-axis, wherein the Z-axis direction displacement The mechanism (3) includes a Z-direction piezoelectric element (10) that expands and contracts in the Z-axis direction, and the X-axis direction scanning mechanism (4) includes a Y-direction piezoelectric element (11) that expands and contracts in the Y-axis direction. The X-direction conversion link machine expands and converts the Y-axis direction expansion and contraction of the Y-direction piezoelectric element (11) into the X-axis direction expansion and contraction. (12), the Y-axis direction scanning mechanism (5) is expanded and contracted in the X-axis direction, and the X-direction piezoelectric element (13) is expanded and contracted in the X-axis direction. A scanning probe microscope comprising the Y-direction conversion link mechanism (14) for enlarging and converting to expansion and contraction in the Y-axis direction.   Each of the conversion link mechanisms (12) and (14) is disposed on both ends of the piezoelectric elements (11) and (13), and is displaced in the longitudinal direction of the piezoelectric element as the piezoelectric elements (11) and (13) are displaced. The end members (15), (16), (31), and (32) that are to be connected to the end members (15), (16), (31), and (32) on both ends are end hinge portions (21), (22), and (23). ) (24) (37) (38) (39) (40) and the intermediate hinge portions (25) (26) (41) (42) are connected to the end members (15) ( 16) (31) and (32) connecting members (19), (20), (35), and (36) arranged on the inner side or the outer side of the straight lines (A) and (B). (11) The connecting members (19), (20) in the direction perpendicular to the longitudinal direction of the piezoelectric element (13) 5) (intermediate portions 36) (17) (18) (33) (34) scanning probe microscope according to claim 1, characterized in that converting the displacement of the.   The position detector (2) so that the position detector (2) moves integrally with the movement of the Z-direction piezoelectric element (10) by the X-axis direction scanning mechanism (4) and the Y-axis direction scanning mechanism (5). The scanning probe microscope according to claim 1 or 2, characterized in that is arranged on the Z-direction piezoelectric element (10) side.   The base end of the cantilever (6) having the tip (1) attached to the tip is connected to the lower end of the Z direction piezoelectric element (10), and the laser beam is transmitted to the center line (O) of the Z direction piezoelectric element (10). Is provided above the Z-direction piezoelectric element (10), and laser reflected light reflected from the back surface of the cantilever (6) is incident on the position detector (2). The scanning probe microscope according to any one of claims 1 to 3, wherein: