JPH02297003A - Detecting part positioning mechanism, piezoelectric element fine adjustment mechanism and scanning type tunnel microscope using them - Google Patents

Abstract

PURPOSE:To automatically execute exact positioning of a detecting part by a simple constitution by driving a hollow cylindrical piezoelectric element, and a fixing means for fixing and release provided on both its end parts, respectively by a prescribed procedure and transferring out successively the detecting part. CONSTITUTION:A piezoelectric element 3 for fixing is attached to a housing 5 so that a probe contact part 31 holds down a probe 1. In the same way, a piezoelectric element 4 for moving and holding having a probe contact part 41 is attached. The elements 3, 4 extend by impressing a positive voltage and hold down the probe 1. Electrodes 23 - 26 are placed by being divided into four equal parts on the outside periphery of a hollow cylindrical piezoelectric element 2. In this state, by inserting the probe 1 into the element 2, and impressing a voltage between the elements 3, 4, an internal electrode 21 and an electrode 22 for (z) in accordance with a prescribed sequence (looper system), the probe 1 is moved in the axial direction. When a position of the probe 1 is determined, the probe 1 is held in a fixed state in a state that a voltage remains impressed to the element 3. Subsequently, by controlling a voltage impressed to the electrode 21 and (z), x and y electrodes 22 - 26, the position in three dimensions of the tip of the probe 1 is determined.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used in the field of optical instruments, analytical instruments, etc., for a detection unit for bringing a minute detection unit such as a probe close to a sample etc. with relatively rough accuracy. The present invention relates to a positioning mechanism, a fine movement mechanism using a hollow cylindrical piezoelectric element that minutely scans the surface of a test object with a similarly positioned detection section, and a scanning tunneling microscope using these mechanisms.

[Prior Art] In recent years, a scanning tunneling microscope (hereinafter abbreviated as STM) that can directly observe the electronic structure of surface atoms of a conductor has been developed [
G, B1nn1g at al,, He1vetica
Physica Acta, 55.726 (1982
)] Recently, as the practical use of STM has progressed, several domestic and overseas companies have started selling STM. Further, a recording/reproducing device to which this is applied (see Japanese Unexamined Patent Publications No. 63-161552 and No. 63-161553) has also been proposed. STM has the advantage of being able to measure real space images with high resolution regardless of whether they are single crystal or amorphous, and can be observed with low power without damaging the medium due to electric current. Operates in the atmosphere and in liquids. Therefore, it can be used for a wide range of purposes, including surface roughness measurement, semiconductors, various materials, optical components, biomolecules, chemical reactions, and ultrafine processing, where demands for atomic structure and analysis are increasing. Many applications are expected.

STM utilizes the fact that when a voltage is applied between a metal probe (probe electrode) and a conductive substance and the probe is brought close to a distance of about inn, a tunnel current flows. This current is extremely sensitive to changes in the distance between the two, and by scanning the probe while keeping the current or the average distance between the two constant, surface information in real space can be obtained with atomic-scale resolution. .

In STM, the sample size that can be mounted is 1 cm.
For larger samples that are about the size of a corner, cut the sample into smaller pieces and then attach them to the sample stand for observation. In the case of the stand-alone head type tunnel unit that has recently appeared for disk surface evaluation, it is sufficient to simply place it on the disk.

During observation, the microdetector is positioned close to the sample using an automatic or manual coarse movement mechanism, and the sample surface is scanned by the fine movement mechanism.

As this coarse movement mechanism, a mechanism using a telescopic element and an electrostatic adsorption element as shown in FIG.
al,, Appl, Phys, Lett,,
40, 178-180 (1982)], a mechanism using magnetic force shown in Fig. 12 [D, P, E, Smlth et al.
Al, Rev, Sci, Instru
m,, 56°1970-197i (1985)]
, a mechanism using a lever as shown in Fig. 13 [J, E,
DeIIluth at al, IBM J, Re
s.

Develop, 30, 396-402 (1986)
], [Murakami et al. 1985 Spring Applied Physics Related Conference Proceedings 2p-ZB-5] and [D, P, E, Sm
1th et al., Rev. Sci.

Instrum,, 57.2630-2631 (19
+16)1 etc. are known.

In Fig. 11, 1 is a probe through which a tunnel current flows;
0 is a sample scanned by the probe 1, 60a is a support base that supports the probe 1, 61 is a metal plate, 62 is an insulating plate, 63 is a metal foot that supports the support base 60a, 64 is a piezoelectric plate, and 65 is a The sample 101 is a scanning piezoelectric element that moves and causes the probe 1 to scan the sample 10.

In FIG. 12, 70 is a support stand that supports the sample 10;
71 is a glass plate, 72 is a leg that has a ball bearing and movably supports the support base 70 on the glass plate 71, 73 is a permanent magnet fixed to the support base 70, and 74 is an electromagnetic magnet through which a pulsed current flows. This is a coil that moves the support base 70 in the direction of the arrow in the figure by applying a strong impact force to the support base 70 via the permanent magnet 73.

In Fig. 13, 1 is a probe through which a tunnel current flows;
0 is a sample scanned by the probe 1, 80 is an arm that supports the sample 10, 81 is a shaft to which the arm 80 is rotatably attached, and 82 is a shaft that supports the shaft 81 so as to be movable in the direction indicated by the arrow in the figure. Bearing 83 is a fulcrum for arm 80 to act as a lever, 8
4 is a stopper that controls the position of the sample 10. In this case, coarse movement is achieved by a screw with a minute pitch, and the commercially available ST
In M, this screw is rotated using a stepping motor for automation.

On the other hand, as a three-dimensional fine movement mechanism that moves along the in-plane (x, y) direction and the unevenness (Z direction) of the sample surface, there is a mechanism [Ch.

Gerber et al., Rev. Sci., I.
nstrum, 57.221-224 (1986
)], a mechanism in which piezoelectrons are assembled in a tower shape [G, F, A
, van da Walle et al., Rev.
, Sci.

In5trutx, 58, 1573-1576
(1985) ), a mechanism using bimorphs [P, M
uralt at al,, IBM J, Res.

Develop, 30, 443-450 (1986
)], a mechanism using a hollow cylindrical piezoelectric element [G, B1nn
1g at al, Rev, Sci.

In5trui+,,57.1888-1689 (1
98B)] is known.

[Problems to be Solved by the Invention] However, in the conventional STM described above, there is a limit to the size of the sample, and since large samples are cut, the sample may be distorted and dust may be generated. and cover the sample surface.

Furthermore, in the case of a stand-alone tunnel unit, since the probe and the sample must be manually brought close to each other in order to place the probe on a disk or the like, the probe may collide with the sample.

On the other hand, regarding the conventional coarse movement mechanism, the coarse movement mechanism shown in FIG. 11, which uses a telescopic element and an electrostatic adsorption element, has the following drawbacks. In other words, the part (surface) that attracts electrostatically
It is necessary to mirror-finish the probe with very high precision, and the movement during electrostatic adsorption and the expansion and contraction of the elastic element lacks smoothness, so it is difficult to bring the probe close because it moves so-called pigeon-walking, and it is difficult to drive in the direction of gravity. The electrostatic adsorption part may not separate due to charge-up, and high voltage is required.

In addition, in the case of the coarse movement mechanism shown in Fig. 12 that uses magnetic force, a pulsed current is passed through the coil and the support base is moved B by electromagnetic impact force, so the friction between the glass plate and the foot is generated. must be kept constant at all times, otherwise the amount and direction of each pulse cannot be controlled, making it unsuitable for driving in the direction of gravity, and the magnetic force from the permanent magnet will affect the surroundings. It is possible to give

Furthermore, in a coarse movement mechanism using a lever as shown in Fig. 13, if the lever ratio is large for fine adjustment, the structure becomes large and
It becomes unstable if the fulcrum parts are not made accurately.

As described above, the conventional coarse movement mechanism has limitations regarding the posture and handling of the device, and also has problems in that the structure is large. Furthermore, those used in vacuum are expensive;
In addition, there are also difficulties in operability, as the operator must actually use his/her hands to attach and detach the probe.

On the other hand, in the above-mentioned conventional three-dimensional fine movement mechanisms, mechanisms in which rod-shaped piezoelectric elements are orthogonal to three axes or mechanisms using bimorphs have relatively low natural frequencies due to their structure, and the vibration between the detection probe and the sample surface is There is a limit to the response frequency when performing control. Furthermore, the tower-shaped mechanism uses many piezoelectric elements due to its structure, and its control system is complicated.

Furthermore, in the case of a mechanism that uses a hollow cylindrical piezoelectric element for scanning in the x and y directions, if the fixing position of the tip of the probe is not precisely controlled, the operating range will change easily each time the probe is replaced due to the structure of the hollow cylindrical piezoelectric element. It goes crazy by a few percent.

In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a detection part positioning mechanism, a piezoelectric element fine movement mechanism, and a scanning type using these, which can automatically perform accurate positioning of a detection part with a simple and compact configuration. Our goal is to provide tunneling microscopes.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention includes a hollow cylindrical piezoelectric element and a detection part holding means for fixing and holding a detection part to both ends of the hollow cylindrical piezoelectric element. In a piezoelectric element fine movement mechanism that slightly moves a detection part by applying a voltage to a hollow cylindrical piezoelectric element, the detection part holding means includes a first fixing means for fixing and releasing the detection part to one end of the hollow cylindrical piezoelectric element; and a second fixing means for fixing and releasing the detection part to and from the other end of the hollow cylindrical piezoelectric element independently, the hollow cylindrical piezoelectric element, the first fixing means, and the second fixing means are fixed in a predetermined position. By driving according to the following procedure, the detection parts are sequentially extended and positioned.

Further, the positioning mechanism of the present invention includes a fixed part, a driven part, a displacement means for displacing the driven part with respect to the fixed part, a first fixing means for fixing and releasing the detection part with respect to the fixed part, and a first fixing means for fixing and releasing the detection part with respect to the fixed part. The detection part is sequentially moved relative to the fixed part by operating the displacement means, the first fixing means, and the second fixing means in a predetermined procedure. I'm trying to position it accordingly.

Furthermore, the scanning tunneling electron microscope of the present invention is provided with the piezoelectric element fine movement mechanism or positioning mechanism, whereby the detection section is positioned with respect to the object to be inspected, and the object to be inspected is scanned by the detection section. .

[Operation] In this configuration, the detection section such as a probe set in the detection section holding means drives the first and second fixing means and the hollow cylindrical piezoelectric element or other displacement means according to a predetermined sequence. As a result, a so-called length-taking main force type operation is performed to move the detection section toward the object to be pinched and position it. That is, the steps of fixing and releasing the detection section by the first fixing means are respectively Step A1 and Step A2, and the similar steps by the second fixing means are Step B1 and Step B2. If the steps of extending and shortening the distance between the two fixing means by the displacement means are step C1 and step C2, respectively, then B
1, A2, C1, A1, B2, C2, B1, A2...
In this sequence, the detection parts are sequentially extended in the direction of the second fixing means. Also, A1, B2, C1, B1, A2,
It moves in the direction of the first fixing means in the following sequence: C2, A1, B2... When measuring the test object, the test object is scanned by slightly moving the probe by driving only the hollow cylindrical piezoelectric element so that the cylindrical shape is curved. Alternatively, there is also a method of driving a piezoelectric element to which a test object is attached. Positioning of the detection unit in the surface direction of the test object is performed by a fine movement mechanism positioning means or the like.

[Example] Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a sectional view showing a first embodiment of the present invention, in which 1 is a probe, 2 is a hollow cylindrical piezoelectric element that moves the probe in three dimensions, and 3
8 is a fixing piezoelectric element for fixing the probe, 6 is a support member for fixing the hollow cylindrical piezoelectric element 2 to the main body 7, 8 is a current-voltage conversion circuit connected to the probe and converts tunneling current into voltage, 8
A is a connector for connecting to a control circuit (not shown), and 9 is a leg that comes into contact with the sample 10. Three legs 9 are provided to support the main body 7 at three points, so that the tip of the probe 1 is at a constant position with respect to the sample 10. It also serves as an electrode for applying a bias voltage to the sample 10.

Next, an observation example will be explained. First, the probe 1 is inserted into the main body 7. At this time, the tip 1 is lower than the surface of the sample 10 in contact with the leg 9.
Make sure that the tip is positioned upward. In this state,
The main body 7 is placed on the sample 10 so that the tip of the probe 1 is located at the observation location. Then, a bias voltage is applied between the probe 1 and the sample 10 via the leg 9 using a circuit similar to the conventional circuit (not shown), and the hollow cylindrical piezoelectric element 2 and the fixing piezoelectric elements 3 at both ends are moved in an inchworm manner. By moving probe 1 to sample 1
0, and stop the approach when the set tunnel current starts to flow between the probe 1 and the sample 10. In this state, the hollow cylindrical piezoelectric element 2 scans the probe 1 to obtain an STM image. When the observation is finished, the probe 1 is retracted upward and the main body 7 is lifted.

FIGS. 2 and 3 are a detailed sectional view of the three-dimensional scanning portion of the probe 1 and a side view as seen from the tip of the probe. In these figures, 1 is a probe, 2 is a hollow cylindrical piezoelectric element,
21 is an internal electrode, 22 is a Z electrode, 23 and 24 are X
(+) and X(-) electrodes, 25 and 26 are y(+)
) and y(-) electrodes. The internal electrodes 21 are x, y
.

and serves as a common electrode for the two electrodes 22 to 26. Further, when a positive voltage is applied to these x, y, and Z circumferential electrodes 22 to 26 with the internal electrode 21 as a ground, the hollow cylindrical piezoelectric element 2 is polarized so as to extend in the axial direction of the cylinder. Reference numeral 3 denotes a fixing piezoelectric element, which is attached to the housing 5 so that the probe contact portion 31 presses the probe 1. Similarly, a movable and holding piezoelectric element 4 having a probe contact portion 41 is attached to the housing 5. These piezoelectric elements 3 and 4 are laminated piezoelectric elements, and are designed to expand when a positive voltage is applied.They firmly press the probe 1 in the extended state, and are separated from the probe 1 in the contracted state. Adjust the positional relationship.

When viewed from the tip side of the probe 1, as shown in Figure 3, x, y
Electrodes 23 to 26 for moving the probe 1 in the direction are arranged so as to divide the outer circumference of the hollow cylindrical piezoelectric element 2 into four equal parts. A V-shaped groove 50 is machined in the housing 5, and the probe 1 is fixed at three points together with the fixing piezoelectric element 3. FIG. 4 is a diagram showing a state in which the housing 5 is assembled to the hollow cylindrical piezoelectric element 2. It has a symmetrical shape in the axial direction.

Next, the movement of the probe 1 will be explained with reference to FIG.

The probe 1 is inserted into a hollow cylindrical piezoelectric element 2, and a fixed piezoelectric element 3 located at an arbitrary position, a moving and holding piezoelectric element 4, and a predetermined sequence between an internal electrode 21 and a Z circumferential electrode 22 are inserted. By applying a voltage according to the inchworm method, the probe 1 is moved in the axial direction.
control the position of Once the position of the probe 1 is determined, as shown in FIG. 2, voltage is kept applied to the fixing piezoelectric element 3 to maintain the state in which the probe 1 is fixed to the housing 5. Here, by controlling the voltages applied to the internal electrode 21 and the x, y, and z electrodes 22 to 26, the three-dimensional position of the tip of the probe 1 can be freely determined.

Note that the positional relationship between the sample 10 and the main body 7 may be upside down compared to the state shown in the figure, and is not limited to this embodiment. The electrodes may be stacked. In addition, if the leg 9 is replaced with a moving mechanism such as an electromagnetic kicker, it is possible to move the probe 1 over a large area of the sample 10.
You can scan a wider area and observe any location.

According to this embodiment, the tunnel units can be placed together in a portion facing the sample 10, and the approach of the probe 1 to the sample 10 can be automated, so a small STM with good operability can be provided.

Furthermore, since the position of the tip of the probe 1 can be determined by the three legs, that is, the tip of the probe 1 can be positioned at the designed position of the hollow cylindrical piezoelectric element 2, so accurate STM of the scanning range can be achieved. Can be provided.

FIG. 5 is a sectional view showing a second embodiment of the invention. The same reference numerals as in FIG. 1 indicate the same elements, and the mechanism for scanning the probe 1 is the same as that shown in FIGS. 2 and 3.

In FIG. 5, 11 is a stage that moves the sample 10 in the x and y directions, 12 is a stand to which the stage 11 is fixed, and the main body 7 and the stand 12 are fitted together. Although not shown, an electrode for applying a bias voltage to the sample 10 is attached to the stage 11 and connected to the sample 10. The operation of the hollow cylindrical piezoelectric element 2 is similar to that of the previous embodiment.

For observation, first, the main body 7 and the stand 12 are separated, and the probe 1 whose tip has been sharpened by electrolytic polishing is inserted into the hollow piezoelectric element 2 from the sample side of the main body 7. However, later, main body 7 and stand 12
Adjust the insertion tray so that the tip of the probe 1 does not come into contact with the surface of the sample 10 when combining the two. Next, the sample 10 is fixed on the stage 11, and a bias electrode is connected. Next, the main body 7
and the stand 12 are combined, and connected to a conventional control circuit system (not shown) via the connector 8A, and initial settings such as the bias voltage between the probe and the sample and the negative feedback value of the tunnel current are performed. The position of the sample 10 to be observed is determined by moving the stage 11. Thereafter, in the same manner as described above, the hollow cylindrical piezoelectric element 2 is moved in a scale-up manner to bring the probe 1 close to the surface of the sample 10, and when the set tunnel current value is reached, the approach is stopped. In this state, the probe 1 is scanned by the hollow cylindrical piezoelectric element 2 to obtain an STM image. When the observation is finished, the probe 1 is separated from the sample 10 using the reverse logic of the approach.

In order to facilitate the replacement of the probe 1, a configuration is also possible in which the probe 1 is inserted and removed from the side opposite to the sample 10. According to this, the probe 1 can be replaced without separating the main body 7 and the stand 12. can do.

FIG. 6 is a sectional view showing a fine movement mechanism according to a third embodiment of the present invention, and FIG. 7 is a side view of the fine movement mechanism as seen from the tip side of the probe. In the figure, 1 is a probe, 2 is a hollow cylindrical piezoelectric element, 21
is an internal electrode, 23 is an electrode for X(+), and 24 is an electrode for X(-). Also, as shown in FIGS. 3 and 4, the y(+) and y(-) electrodes are located at the X electrode 23°2.
The internal electrode 21 is provided on the outer circumferential surface of the hollow cylindrical piezoelectric element 2 in a shape perpendicular to x.
, and serves as a common electrode for the y electrodes. In addition, internal electrode 2
X with 1 as ground.

When a positive voltage is applied to the y electrode, the hollow cylindrical element 2 is polarized so as to extend in the axial direction of the cylinder. 3'
4' is a hollow cylindrical piezoelectric element for fixation, 4' is a hollow cylindrical piezoelectric element for moving and holding, 32 is a fixing electrode provided on the outer periphery of piezoelectric element 3', and 42 is provided on the outer periphery of piezoelectric element 4'. The movable electrodes 52 provided are connected to the probe 1 on the inside thereof.
This is a chuck for holding. The piezoelectric element 3' is polarized so that its cylinder expands when a voltage is applied, and the piezoelectric element 4' is polarized so that its cylinder contracts when a voltage is applied. The probe contact portion 31 is designed to fix the probe 1 in a state where no voltage is applied to these piezoelectric elements 3' and 4'.
The chuck 52 is adjusted so that the probe 1 can be separated from the probe 1 and fixed by applying a voltage.

In this mechanism, coarse movement in the Z direction and fine movement in three dimensions of the probe 1 can be performed in the same manner as in the previous embodiment, but the drive signal in the Z direction is applied to all x and y electrodes,
This allows movement in two directions.

In this example, hollow cylindrical piezoelectric elements 2°3', 4
' are separate parts, but they may be an integral structure. Further, the shape of the probe 1, which is the detection part, does not have to be cylindrical, and may also be a square prism, a hexagonal prism, etc., and is not limited to the embodiment.

FIGS. 8(a) and 8(b) are a side view and a perspective view 1 showing a fourth embodiment of the present invention, in which 1 is a probe;
0 is a sample, 13 is a piezoelectric element for coarse movement, and 16 and 17 are a fixed part and a driven part attached to both ends of the piezoelectric element 13 for coarse movement in the direction of expansion and contraction.

The coarse movement piezoelectric element 13 is polarized so that it expands when a voltage is applied. 14 is a fixing piezoelectric element fixed to the fixed part 16, and 15 is a fixing piezoelectric element fixed to the driven part 17. These fixing piezoelectric elements 14, 15 are polarized so that they contract when voltage is applied and expand when voltage application is stopped. Further, the probe 1 is adjusted so that the fixing piezoelectric elements 14 and 15 are pressed in an extended state and released in a contracted state to move in the axial direction. 19 is a base to which the fixing part 16 is attached; 18 is a sample scanning piezoelectric element that is attached to the base 19 and holds the sample 2 and moves it slightly in the scanning direction; 50 is a piezoelectric element for sample scanning that allows the probe 1 to move in a straight line; The fixing part 16 and the driven part 17 on the opposite side of the fixing piezoelectric element 4
It is a ■-shaped groove machined into the part.

Next, the operation of this device will be explained.

First, the probe 1 is inserted and fixed. That is, a voltage is applied to the fixing piezoelectric elements 14.15 to shorten them, and the probe 1 is inserted into the space between these piezoelectric elements 14.15 and the ■-shaped groove 50 so as to cover both of the fixation piezoelectric elements 14.15. In this state, the voltage application to the fixing piezoelectric elements 14 and 15 is stopped and the probe 1 is pressed down.

Next, perform coarse movement of the probe. That is, by first applying a voltage to the piezoelectric element 15 for fixation and then to the piezoelectric element 13 for coarse movement, the piezoelectric element 14 for fixation is used as a fixed point, and the driven part 17 is adjusted according to the elongation of the piezoelectric element 13 for coarse movement. Move in the direction of entering the figure. At this point, the voltage application to the fixing piezoelectric element 15 is stopped and the probe 1 is pressed down. Then, a voltage is applied to the fixed piezoelectric element 14 to release the fixation of the probe, and the voltage application to the coarse movement piezoelectric element 13 is stopped. When the coarse movement piezoelectric element 13 is thereby shortened, the voltage of the fixing piezoelectric element 14 is stopped and the probe 1 is fixed. The amount of movement of the probe 1 in this series of operations is the length of the elongation of the coarse movement piezoelectric element 13, and for example, when a commercially available laminated piezoelectric element is used, 50
The amount of elongation is 3 μm at an applied voltage of V. This amount of elongation can be changed by adjusting the voltage application value. By repeating this series of operations, the probe 1 can be roughly moved in the direction of the sample 10 by an arbitrary distance. It can also be moved in the opposite direction by a reverse operation. After the probe 1 is positioned at a predetermined position with respect to the sample 2 in this manner, the sample 10 is slightly moved by the sample piezoelectric element 18 and the sample 10 is scanned with the probe 1 for observation.

When the observation is completed, move the probe 1 a little away from the sample 10 by coarse movement in the opposite direction as described above, and then move the fixing piezoelectric element 14.15.
Apply voltage to release the fixation of the probe 1. and remove probe 1.

FIG. 9 and FIG. 10 are a perspective view and a sectional view showing a fifth embodiment of the present invention, and show an example in which an automatic probe exchange mechanism is provided. In the figure, 51a is a probe holder, 1a to 1d are probes, and the probes 1a to 1d are lightly held and attached to the probe holder 51a by a probe holder 52a using spring force. The probe holder 51a is attached to the base 19 via a rotary drive manual part 59 and a bearing 60, and is rotated by applying a rotational force to the rotary drive input part 59 by a rotation mechanism (not shown). The above-mentioned coarse movement mechanism is incorporated in the lower part of the probe holder 51a on the base 19 side. The figure shows a state in which the probe 1a is approaching the sample 10.

The operations of the coarse movement piezoelectric element 13, the fixed piezoelectric elements 14 and 15, the fixed part 16, and the driven part 17 are the same as in the previous embodiment.

However, the probe holder 51a on the opposite side of the probe with respect to the piezoelectric element 14.15 has a movable piece 55.58, and this movable piece is designed to move freely in the direction of the probe axis. It returns to the neutral position by elastic force. 57 is a vertically movable plate to which the fixed portion 16 is attached, and 58 is a vertically movable plate driving device that drives the vertically movable plate 57 in the vertical direction indicated by arrow C in the figure to perform positioning with high precision. In the rest position of the probe holder 51a, the fixing piezoelectric element 14.15 is inserted into the opening 53.54, and such positioning of the probe holder 51a is controlled by a positioning sensor (not shown).

Next, the procedure for replacing the probe will be explained. First, the probe 1a approaching the sample 10 is moved by the coarse movement and fixation piezoelectric elements 13.
, 14.15 can be retracted by driving. Next, lower the piezoelectric element by lowering the vertically movable plate 57 (at this time, the probe is held in the probe holder 51a at three locations by the movable piece 55.56 and the probe holder 52) opening 53.5
4 and the piezoelectric element 14.15 from the probe holder 5.
Rotate 1a until the probe 1b reaches the openings 53° and 54, then stop. Then, by raising the vertically movable plate 57, the probe 1b is held down by the piezoelectric elements 14 and 15. Thereafter, the piezoelectric elements 13 to 15 are driven to bring the probe 1b closer to the sample 10, thereby completing the probe exchange. Since each probe is held down by the probe holder 51a with elastic force, it can be easily inserted and removed. Note that the number of probes that can be attached to the probe holder 51a is not limited to four, but may be any number as long as the configuration allows it. Further, the probe holder 51a may be replaceable.

[Effects of the Invention] As explained above, according to the present invention, a mechanism for moving a minute detection section such as a probe using an element or the like is used to move a minute detection section such as a probe by itself. Since the probe is positioned with respect to the test object, there is no difference in posture, and the position control accuracy of the probe light is improved. In addition, the STM is small and easy to operate, including an automatic probe exchange function.
can be provided.

In addition, since the first and second fixing means are provided at both ends of the hollow cylindrical piezoelectric element, a small and simple configuration allows the detection unit to be transferred and fixed with relatively rough accuracy in the two axial directions, and the x, Fine three-dimensional positioning in the y- and z-axis directions can be easily performed. Moreover, a conventional control system can be used.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a scanning tunneling microscope according to a first embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views and an exploration 4 is a perspective view showing the assembled state of the piezoelectric element fine movement mechanism of FIG. 2, and FIG. 5 is a side view of the piezoelectric element fine movement mechanism of FIG. A cross-sectional view of a microscope, FIGS. 6 and 7 are a cross-sectional view of a piezoelectric element fine movement mechanism according to a third embodiment of the present invention, a side view as seen from the tip of the probe, and FIGS. 8 (a) and (b). ) are a side view and a perspective view of a probe positioning mechanism according to a fourth embodiment of the present invention, and FIGS. 9 and 10 are a side view and a perspective view of a probe positioning mechanism according to a fifth embodiment of the present invention. The perspective view and sectional view of , and FIGS. 11 to 13 respectively show the probe positioning according to the conventional example (
FIG. 2 is a cross-sectional view, a perspective view, and a side view of the coarse movement mechanism. 1: Probe, 2: Hollow cylindrical piezoelectric element, 3: Fixed piezoelectric element, 4: Moving and holding piezoelectric element, 6: Support member, 7: Main body, 9: Legs, 10: Sample, 11: Stage 21: Internal electrode, 222 Z electrode, 23: X(+) electrode, 24: xC-) electrode, 25: y(+) electrode, 26: y(-) electrode, 32: Fixing electrode, 42: Moving electrode, 31.41: Probe contact part, 5: Housing, 50: V-shaped groove, 13: Coarse movement piezoelectric element, 14.15 + Fixed piezoelectric element, 16: Fixed part, 17: Followed part, 19: Base, 50: V-shaped groove, 51a: Probe holder, 52a: Probe holder, 53.54: Opening, 55.56: Movable piece, 57: Vertical moving plate.

Claims (17)

[Claims] (1) Piezoelectric element fine movement that includes a hollow cylindrical piezoelectric element and a detection part holding means that fixes and holds a detection part at both ends of the piezoelectric element, and applies voltage to the hollow cylindrical piezoelectric element to slightly move the detection part. In the mechanism, the detection part holding means includes first fixing means for fixing and releasing the detection part to one end of the hollow cylindrical piezoelectric element, and independently of this, the detection part holding means to the other end of the hollow cylindrical piezoelectric element. It is provided with a second fixing means that fixes and releases the detection part, and by driving the hollow cylindrical piezoelectric element, the first fixing means, and the second fixing means in a predetermined procedure, the detection part is sequentially extended and positioned. Features a piezoelectric element fine movement mechanism. (2) The piezoelectric element fine movement mechanism according to claim 1, wherein the first and second fixing means include fixing piezoelectric elements. (3) The piezoelectric element fine movement mechanism according to claim 2, wherein the fixing piezoelectric element is of a laminated type. (4) The piezoelectric element fine movement mechanism according to claim 2, wherein the fixing piezoelectric element is a part of the hollow cylindrical piezoelectric element. (5) A fixed part, a driven part, a displacement means for displacing the driven part with respect to the fixed part, a first fixing means for fixing and releasing the detection part with respect to the fixed part, and a first fixing means for fixing and releasing the detection part with respect to the driven part. It is characterized by comprising a second fixing means that opens, and by operating the displacement means, the first fixing means, and the second fixing means in a predetermined sequence, the detection part is sequentially moved and positioned relative to the fixing part. positioning mechanism. (6) The positioning mechanism according to claim 5, wherein the detection section is a probe of a scanning tunneling microscope or a device applying the same. (7) The positioning mechanism according to claim 6, wherein the displacement means utilizes an element that converts electrical energy into mechanical energy by expansion and contraction. (8) The positioning mechanism according to claim 7, wherein the element is a piezoelectric element. (9) The positioning mechanism according to claim 8, wherein the piezoelectric element is of a laminated type. (10) The positioning mechanism according to claim 6, further comprising means for guiding the detection section to move in a straight line. (11) The positioning device according to claim 6, further comprising means for holding a plurality of the probes and transferring the probes to and from the first and second fixing means. (12) A scanning tunneling electron microscope comprising the piezoelectric element fine movement mechanism according to claim 1, whereby the detection section is positioned with respect to the object to be inspected, and the object to be inspected is scanned by the detection section. (13) Claim 1 further comprising a fine movement mechanism positioning means for positioning the piezoelectric element fine movement mechanism with respect to the test object by moving the piezoelectric element fine movement mechanism while holding the piezoelectric element fine movement mechanism above the test object.
2. The scanning tunneling electron microscope according to 2. (14) The scanning tunneling electron microscope according to claim 13, wherein the contact portion of the fine movement mechanism positioning means with respect to the test object also serves as an electrode for applying a bias voltage to the test object. (15) The scanning tunneling electron microscope according to claim 13, wherein the fine movement mechanism positioning means contacts the object at three locations. (16) The scanning tunneling electron microscope according to claim 12, further comprising a fine movement mechanism positioning means for positioning the test object with respect to the piezoelectric element fine movement mechanism by holding or placing and moving the test object. (17) An apparatus to which the scanning tunneling electron microscope according to claim 12 is applied.