JP3065714B2 - Fine movement mechanism of scanning tunneling microscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine movement mechanism of a scanning tunneling microscope, and more particularly to a fine movement mechanism of a scanning tunneling microscope capable of improving a scanning movement ability and performing accurate measurement.

[0002]

2. Description of the Related Art A conventional scanning tunneling microscope (hereinafter referred to as S
Various types of fine movement mechanisms (referred to as TM) have been proposed. For example, as disclosed in Japanese Patent Application Laid-Open No. 63-236992, a plurality of electrodes are arranged at predetermined positions on the inner peripheral surface and the outer peripheral surface of a cylindrical piezo element, and a voltage is applied by appropriately combining the respective electrodes. When applied, the probe is configured to perform fine movement of the probe or scanning movement on the surface of the sample in accordance with the unevenness of the sample. Specifically, approaching the probe
The fine movement of the retreat is performed by the axial expansion and contraction deformation of the cylindrical piezo element, and the scanning movement of the probe is performed by the bending deformation of the piezo element. There is also a tripod-type fine movement mechanism. In this fine movement mechanism, three rod-shaped piezo elements arranged at right angles to each other are attached to a base member, a probe holder is provided at the tip of one of the piezo elements, and the probe is moved toward and away from the sample while being moved. ,
The remaining two piezo elements are configured to scan the probe along the sample surface.

[0003]

In the conventional STM fine movement mechanism having a cylindrical piezo element, if the scanning range of the probe is to be widened, the axial length of the cylindrical piezo element must be increased. As a result, there is a problem in that the natural frequency is reduced, the influence of external vibration is great, and high-precision measurement cannot be performed. Also, in the tripod-type fine movement mechanism, when the approaching / retreating piezo element performs the expansion and contraction operation, the expansion and contraction operation must be performed while being restricted by the two piezo elements for scanning along the sample surface. There is a problem that there is a problem that a fine movement in the axial direction of the probe cannot be performed with high accuracy.

In the conventional STM fine movement mechanism, since the sample and the fine movement mechanism are arranged close to each other, when observing a high-temperature sample, the accuracy of the piezo element of the fine movement mechanism deteriorates due to the heat of the sample. There was also a problem that highly accurate measurement could not be performed.

In view of the above problems, an object of the present invention is to provide a fine movement mechanism of an STM having a structure capable of performing measurement with high accuracy over a wide scanning range regardless of the temperature state of a sample. is there.

[0006]

The fine movement mechanism of the STM according to the present invention is configured as follows to achieve the above object. 1. A first piezo element for finely moving the probe corresponding to the unevenness of the sample, and a second and a third for probe scanning arranged at right angles to the first piezo element and at right angles to each other. ST provided with two piezo elements on a base member
A fine movement mechanism of M, wherein a probe holder is fixed to one end of a first piezo element, and a scanning magnifying member is connected to the other end, and this scanning magnifying member is connected via a strain generating member having a small sectional area. In addition to being fixed to the base member, one end of each of the second and third piezo elements is connected to a portion near the strain generating portion of the scanning magnifying member, and the other end is fixed to the base member. 2. A first piezo element for finely moving the probe corresponding to the unevenness of the sample, and a second and a third for probe scanning arranged at right angles to the first piezo element and at right angles to each other. ST provided with two piezo elements on a base member
M, wherein a scanning magnifying member having a probe holder attached thereto is fixed to one end of a first piezo element, and a connecting member is attached to the other end of the first piezo element. A strain-generating portion having a small area is provided, the strain-generating portion is fixed to the base member, one end of each of the second and third piezo elements is connected to the connecting member, and the other end is fixed to the base member. 3. In the second configuration, preferably, the scan enlarging member is formed of a material having low thermal conductivity.

[0007]

In the fine movement mechanism of the first STM according to the present invention, a scanning magnifying member is provided, and the expansion / contraction operation by the scanning piezo element is amplified by bending deformation of the scanning magnifying member. Therefore, the scanning range can be expanded. The scanning piezo element is
Since the scanning magnifying member is fixed to the base portion, the magnifying effect can be sufficiently exhibited without making the scanning magnifying member long in dimension. Further, since it is not necessary to increase the size, the size and weight can be reduced, and the natural vibration in the fine movement mechanism can be increased.
In addition, since a deformable strain-producing portion is provided at the base of the scanning magnifying member, a large load is not applied to the scanning piezo element.
Scanning properties can be improved. In the fine movement mechanism of the second STM according to the present invention, the scanning magnifying member is formed of a material having a small thermal conductivity, and the arrangement relationship between the piezo element and the scanning magnifying member in the Z-axis direction is reversed. Sometimes, the scanning magnifying member blocks heat and does not propagate heat to each piezo element, so that in addition to the above-described operation, high accuracy can be exhibited even in measurement of a high-temperature sample.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a front view, and FIG. 2 is a side view.
The fine movement mechanism of the STM according to this embodiment has a configuration of a tripod system. In the illustrated example, the configuration of the entire STM device is not shown, but only the main part of the probe and the fine movement mechanism for moving the probe is shown. In FIG. 1, reference numeral 1 denotes a probe, and the probe 1 is fixed to a probe holder 3 using screws 2. 4
Is a piezo element for finely moving the probe 1 in accordance with irregularities on the surface of the sample (not shown). The piezo element 4 includes the probe 1
Is an actuator for making fine movement in the axial direction (Z-axis direction). A probe holder 3 to which the probe 1 is attached is fixed to the left end of the piezo element 3 in FIG. Tip holder 3
Is fixed to the piezo element 4 with an adhesive. A scanning magnifying member 5 is attached to the right end of the piezo element 4 in the drawing. At the base end of the scanning magnifying member 5, a strain-generating portion 5 having a reduced cross-sectional area
a is formed, and the scanning magnifying member 5 is fixed to the base member 6 via the strain generating portion 5a.

Reference numerals 7 and 8 denote piezo elements for scanning the probe 1 on the surface of the sample. As shown in FIG. 2, the piezo elements 7 and 8 are disposed so as to form a right angle. The piezo element 7 is, for example, an actuator in the X-axis direction, and the piezo element 8 is an actuator in the Y-axis direction. is there. One end of each of the piezo elements 7 and 8 is attached to a portion of the scanning magnifying member 5 adjacent to the strain generating portion with an adhesive. The other ends of the piezo elements 7 and 8 are fixed to the base member 6 with an adhesive.

According to the fine movement mechanism of the probe 1 having the above-described configuration, when the probe 1 is scanned, a voltage is applied to the operation piezo elements 7 and 8 in the X and Y directions to expand and contract, thereby causing the strain generating section. 5
The scanning movement is performed by causing the bending deformation in a. In the scanning movement based on such a structure, the strain generating portion 5a and the piezo elements 7 and 8 are disposed close to each other, and the scan enlarging member 5 has a required length. Even with the expansion and contraction amount, the probe 1 can obtain a large scanning movement amount that is enlarged. In this case, the length of the scanning magnifying member 5 does not need to be so large. Therefore, the weight of the entire fine movement mechanism can be reduced. Also, the part to be deformed for scanning movement is
Since the strain generating portion 5a has a small cross-sectional area, the load applied to the piezo elements 7 and 8 is light, and the expansion and contraction operation can be performed accurately and at high speed. Therefore, according to the above configuration,
The size and weight of the fine movement mechanism can be reduced, the natural frequency can be set high, and highly accurate measurement can be performed.

FIG. 3 shows a second embodiment of the present invention, and is a front view of a fine movement mechanism. The fine movement mechanism according to this embodiment is suitable for measuring a high-temperature sample. Substantially the same elements described in the above embodiment are denoted by the same reference numerals. In FIG. 3, the probe 1, screw 2, probe holder 3, and piezo elements 4, 7, 8 are as described in the above embodiment. The probe holder 3 is attached to one end of the scanning magnifying member 11 with an adhesive, and the other end of the scanning magnifying member 11 has the Z
The axial piezo element 4 is attached with an adhesive. The scanning magnifying member 11 is formed of ceramic having a low thermal conductivity. A connecting member 12 is connected to the other end of the piezo element 4 with an adhesive, and the connecting member 12 is fixed to the base 6 via a strain-generating portion 12a having a small sectional area. X, Y
One end of each of the scanning piezo elements 7 and 8 is connected to the connecting member 1.
2 is fixed with an adhesive. Other configurations are the same as those of the above embodiment.

In the fine movement mechanism having the above-described structure, a mechanism having a high natural vibration can be provided as in the case of the above-described embodiment. High temperature propagation to the piezo elements 4, 7, 8 can be suppressed, and high measurement accuracy can be obtained.

[0013]

As is apparent from the above description, according to the present invention, a wide scanning range can be scanned, and the fine movement mechanism can be reduced in size and weight. In addition, since the natural frequency can be set high by reducing the weight, the sensitivity of the probe of the STM can be increased, and the measurement accuracy can be increased. Further, when measuring a high-temperature sample, since each piezo element of the fine movement mechanism is arranged with a member having a scanning magnification function and a heat insulating property, the piezo element can be protected, Even high-temperature samples can be measured with high accuracy.

[Brief description of the drawings]

FIG. 1 is a front view showing a typical embodiment of a fine movement mechanism of an STM according to the present invention.

FIG. 2 is a side view of the fine movement mechanism of the STM according to the present invention shown in FIG.

FIG. 3 is a front view showing another embodiment of the fine movement mechanism of the STM according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 probe 3 probe holder 4 piezo element in Z-axis direction 5 scanning magnifying member 5a strain-generating portion 6 base member 7 piezo element in X-axis direction 8 piezo element in Y-axis direction 11 scanning magnifying member 12 connecting member 12a strain-generating portion

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Osamu Yamada 882 Ma, Katsuta-shi, Ibaraki Prefecture Inside Naka Works, Hitachi, Ltd. (72) Inventor Akira Hashimoto 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. References JP-A-4-265803 (JP, A) JP-A-3-35104 (JP, A) JP-A-63-265573 (JP, A) Japanese Utility Model Showa 64-48862 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) G01B 7/34 G01N 13/10-13/24 G05D 3/00-3/20 H01J 37/28 JICST file (JOIS)

Claims (3)

(57) [Claims] 1. A first piezo element for finely moving a probe corresponding to unevenness of a sample, and a first piezo element arranged at right angles to the first piezo element and arranged at right angles to each other for scanning a probe. In a fine movement mechanism of a scanning tunneling microscope having a base member having second and third piezo elements, a probe holder is fixed to one end of the first piezo element, and a scanning magnifying member is connected to the other end. Then, the scanning magnifying member is fixed to the base member via a strain generating portion having a small sectional area, and one end of each of the second and third piezo elements is close to the strain generating portion of the scanning magnifying member. A fine movement mechanism of the scanning tunnel microscope, wherein the other end is fixed to the base member. 2. A first piezo element for finely moving a probe corresponding to unevenness of a sample, and a first piezo element arranged at right angles to the first piezo element and arranged at right angles to each other for scanning a probe. In a fine movement mechanism of a scanning tunneling microscope having a base member having second and third two piezo elements, a scanning magnifying member having a probe holder attached thereto is fixed to one end of the first piezo element. A connecting member is attached to the other end of the first piezo element, and a strain generating portion having a small sectional area is provided on the connecting member, and the strain generating portion is fixed to the base member, and the second and third piezoelectric elements are fixed. A fine movement mechanism for a scanning tunneling microscope, wherein one end of each element is connected to the connecting member, and the other end is fixed to the base member. 3. The fine movement mechanism for a scanning tunneling microscope according to claim 2, wherein said scanning magnifying member is formed of a material having a low thermal conductivity.