JPH032605A - Minute driving mechanism and its drive control method - Google Patents

Abstract

PURPOSE:To eliminate the backlash between a piezoelectric part and a receiving part and to make it possible to perform efficient, stable, minute driving by providing a second piezoelectric element which is expanded and contracted approximately perpendicularly with the moving plane of a first piezoelectric element on an electrostatic chuck. CONSTITUTION:Four electrostatic chuck electrodes 60a-60d are arranged on a base electrode 10 of a scanning type tunnel microscope. The chuck structure is composed of the following parts: a moving stage 61 for a metal pipe, a metal lic supporting stage 63 on which a receiving part 62 in a recess shape is formed; and a second piezoelectric element 64 which is held between the stages 61 and 63 and expanded and contracted perpendicularly with a driving piezoelectric element 30. Power sources are connected to the respective parts. In this constitu tion, a voltage is applied between the base electrode 10 and each electrostatic chuck, and the voltage is turned ON and OFF. Thus chucking and releasing are carried out. In this way, a sample 40 and a probe 50 are finely moved. Since the second piezoelectric element 64 is provided, basklash and dead zones are eliminated, and the stable, minute driving can be performed.

Description

[Detailed Description of the Invention] [Purpose 1 of Q-Mei (Industrial Application Field) The present invention is for bringing a measurement sample close to the probe in a scanning tunneling microscope (S-'M), etc. The present invention relates to a method for controlling the drive ij of four different micro-vJ-drive LeJ machines.

(Prior Art) FIG. 5 is a strategic diagram showing a conventional @dynamic drive mechanism used in a scanning tunneling microscope t,Q (STM). As shown in this figure, four electrostatic chuck electrodes (driving legs >20a, 20b, 20c, 20d) are arranged on the base electrode 441 (base plate) 10 at 90'' intervals along the circumference. (See Figure 6).The base electrode 10 has
A dielectric film 11 with a high dielectric constant is laminated on the surface thereof,
Static electricity 1! Tsuku electrodes 20a, 20b, 20c, 2
0d (1) Convex receiving portions 21 are formed at the upper portions.

Static electricity ↑? Tsuku ff1J420a, 20b,
On 20c and 2Od, a disc-shaped drive piezoelectric element 30 is arranged, which has a spherical connecting member 31 fixed to its lower part corresponding to the position of the receiving part 21, and each connecting member 31 is connected to the receiving part 21, respectively. is installed on. Also, static electricity chisek thunder effect 20d1. : A probe 50 is disposed on the base electrode 10 and facing the probe 50 in the vicinity of the measurement sample 40 set up.

Although omitted in the figure, the electrostatic chuck FF120a
, 20b, 20c, 20d and base lK10,
A switch and a power source are connected to each of the driving F [lightning water element 30].

The conventional fine movement drive mechanism is configured as described above, and by operating a switch (not shown), for example, turns on the voltage applied to the electrostatic 1V electrode 20G,
By turning off the application type J1 to 20a, 20b, and 20d, the electrostatic chuck electrode 20C is electrostatically chucked (electrostatically attracted) to the base electrode 10, and the electrostatic pickup A20a, 20b, 20d is released (released from suction). Then, by turning on the voltage applied to the driving piezoelectric element 30 in this state, the driving piezoelectric element 30 is turned on.
extends in the direction of the static 7h titter electrode 20a. After that, the voltage applied to the electrostatic jack lightning pole 20a is turned on, and the static? 11?
Turn off the FD voltage applied to the f-contact electrodes 20b, 20c, and 20d, turn off the electrostatic chuck m20a, release the electrostatic V-tuck electrodes 20b, 20c, and 20d, and release the piezoelectric cable for driving. Application to 30? T? Turn off fE and electrostatically pull the piezoelectric cable 30 for driving 21H.
Shrink it toward the 4i20a direction. At this time, the connecting portion 4431 fixed to the lower part of the drive piezoelectric element 30
Since it is attached to the receiving part 21 formed in the
C electrostatic chuck m20a according to the amount of expansion and contraction of Ichisakuko 30
, 20b, 20c, 20d b move together.

(Problems to be solved by the invention) By the way, electrostatic chucks (Les 20a, 20b, 200.
The surface of the chip electrode 10 on which 20 (I moves) has a warp of 10 to 20 μm or more between the center and outer portions due to machining viscosity, etc. Similarly, the center of the surface of the driving piezoelectric element 30 Since there is further distortion such as warpage between the outer part and the outer part, the surface finish [α] is not good. vtsukurai A20a, 20b, 20c, 20
When attached to each receiving portion 21 formed at the -F portion of cl, the contact position between each connecting member 31 and the receiving portion 21 is not on the same plane, and a shift occurs.

In this way, if the surface precision of the base electrodes KA20a, 20b, 2oc, 20d is poor, the electrostatic chip electrodes 20a, 20b, 2
0c.

Shakiness occurs between each receiving portion 21 of 20d and the connecting member 31 fixed to the lower part of the driving piezoelectric element 30.

For this reason, the driving piezoelectric element 30 is expanded and contracted by controlling the applied voltage on and off to form each electrostatic chuck [20a, 2
When driving 0b, 20c, and 20d, a dead zone is formed, resulting in a decrease in driving efficiency, and in some cases, there is a fear that driving may not be possible.

The present invention aims to solve the above-mentioned problems by providing a fine movement drive mechanism 1-4 that is capable of efficient and stable fine movement drive.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the fine movement drive mechanism according to the present invention includes a base electrode and a plurality of static plates arranged at predetermined positions on the base electrode. an electric chuck pole; a dog first piezoelectric element extendable and retractable in a direction within a predetermined movement plane for moving these electrostatic chuck electrodes; The piezoelectric device is characterized by comprising: a second piezoelectric element that can be expanded and contracted substantially orthogonally; and a connecting means for transmitting the expansion and contraction driving force of the first piezoelectric element to the second piezoelectric element.

Further, in the drive control method for a fine movement drive mechanism according to the present invention, the first and second piezoelectric elements are moved via the coupling means by applying a voltage to at least two of the second piezoelectric elements. At the same time, the electrostatic knock electrode corresponding to the second piezoelectric element was released from adsorption, and at least one other electrostatic knock electrode was held in an adsorbed state. Later, +'+ff 1st
It is characterized in that it is driven by applying a voltage to the piezoelectric element.

(Function) According to the present invention, by applying a voltage to at least two of the second piezoelectric elements, the first and second piezoelectric elements are
The piezoelectric elements are connected without gaps in the direction of movement, allowing for excellent fine movement.

(Example) Hereinafter, the present invention will be described in detail with reference to an illustrated example. Incidentally, members that are the same as those in the prior art will be described using the same reference numerals as A and 1.

FIG. 1 is a schematic diagram of a platform in which a fine movement drive mechanism according to the present invention is applied to a scanning tunneling microscope (STM). As shown in this figure, on the base '11fi14i (base plate) 10, there are four electrostatic V-took electrodes (drive legs) 60a, 6Qb 60 at intervals of 90"rH along the circumference.
c, 60d are placed. (See Figure 2). Electrostatic tick 441!60a, 601), 6QC,
Reference numeral 60d denotes a metal moving table 61 for moving the base electrode 10F-, a metal supporting table 63 having a concave receiving part 62 formed in the upper part, and a piezoelectric device sandwiched between the moving table 61 and the supporting table 63. element (second 1-wire element) 64 (see FIG. 3).

On the surface of the base electrode 10, an attracting film 11 of IE'&+A particles is laminated, and the surface is further polished with a resin film (not shown) to improve the flatness. ing. Furthermore, the electrostatic chip 1 that is in contact with the dielectric film 11 of the base electrode 10?
The movable stage 61 of the electrodes 60a, 60b, 60c, and 60d has a mirror finish to improve the plane 1α.

Base electrode 10 and electrostatic X7 electrodes 60a, 60b
, 60c, 60d and the piezoelectric element 64 are connected to a switch 70.71 and a power source 80.81, respectively.
'3, base electrode 10 and electrostatic charge (・Tsukuden ff160
By controlling on/off the voltage applied between a, 60b, 60c, and 60d, titration (adsorption) and release (suck release) are performed (details will be described later). When the voltage is applied, the electrodes 60a and 60b are compressed in the thickness direction (height direction) and the electrostatic charge is applied.
, 6oa, 60d 11rj body extends in the height direction.

Electrostatic chips 160a, 60b, 60c, 6
Disc-shaped driving piezoelectric elements (first piezoelectric elements) 30 having spherical connecting members 31 fixed to their lower parts corresponding to the positions of the receiving parts 62 are disposed on each support base 63 of 0d. , each connecting member 31 is attached to a receiving portion 62, respectively. In addition, the number of measurement samples 40 is set on the electrostatic chamber 60d.
A probe 50 is disposed oppositely on the base electrode 10 in the vicinity of the base electrode 10 .

Next, the above-mentioned fine movement drive mechanism is set to Y'+111, for example.
The case of fine movement #J in the (1-) direction will be described with reference to FIGS. 4(a), (b), and (c). First, 3
Two electrostatic chip electrodes 60a, 60G and 60b
By operating the switch 71, a voltage is applied from the power supply 81 to each piezoelectric cord 64 (or 60d) to distort it in the thickness direction, and the remaining electrostatic cord 11
b) Turn off the applied voltage. That is, a voltage is applied to the electrostatic tilt electrodes 60a and 60G disposed along the moving direction and the piezoelectric cord 64 of the other electrostatic tilt electrode 60b (or 60d). Electric Chi P
Tsuku lightning pole 60a, 60C and 60b (or 60d)
is the remaining electrostatic fI7 current 44i60d (or 60b)
Since it extends more in the vertical direction, the electrostatic tip/tsuku electrode 60a
, 60C and 60b (or 60d) support stands 6
The connection member 31 of the drive EJ+ piezoelectric element 30 is attached to the receiving part 62 of 3.
However, it is installed without any looseness. That is, the drive pressure 7n cable 30 connects the three electrostatic currents KA60a, 60c and 60b (or 60b) via the connecting member 31.
0d).

Next, operate the switch 70 to apply voltage from the power supply 80 to the electrostatic chuck electrode 60C1, and
The voltage applied to 0a, 60b, and 60d is turned off, and the electrostatic chuck T1 pole 60c is electrostatically chucked (electrostatically attracted) to the base electrode 10, and the electrostatic chuck electrodes 60d, 60b are
, release (release the adsorption) 60d (negative 14 figure (a)
). In this state, a voltage is applied to the driving piezoelectric element 30 to extend the C1 driving piezoelectric element 30 in the radial direction from the center (FIG. 4(b)). In this state, the electrostatic block 17 electrode 60C is tilted, so the drive piezoelectric element 30 extends in the Y-axis (+) direction. Next, by operating the switch 70, the power source 80 is connected to the electrostatic chuck electrode 60.
By applying a voltage to the electrostatic chuck electrodes 60b and 6
Turn off the voltage applied to 0c and 60d, and turn off the electrostatic charge t? The remaining electrostatic boot electrodes 60b, 60c, and 60d are released by clicking the pick electrode 60a. Then, in this state, the voltage applied to the drive piezoelectric cable 301\ is turned off, and the drive piezoelectric element 30 is contracted in the Y-axis (1-) direction (FIG. 4(C)).

At this time, three electrostatic chuck charges? 460a, 60C, and 60b (or 60d), the connecting member 31 of the F lightning element 30 (for driving) is attached to the receiving part 62 of each support stand 63 (or 60d).
Since the driving piezoelectric cord 30 is attached without any curvature, when the drive piezoelectric cord 30 expands or contracts in the Y-axis (+) direction, the first condylar tube t+y ?
ffi+4i, 60a, 60b, 60c
, 60d moves as one without any wobbling, and the measurement sample 40 attached to the electrostatic chuck center pole 60G moves efficiently and stably in the Y-axis (G) direction according to the amount of expansion and contraction of the drive piezoelectric element 30. do.

In addition, when moving the above-mentioned fine movement drive mechanism in the
A voltage is applied to each piezoelectric element 64 of 60d and 60a (or 60C) to distort it in the thickness direction, and the remaining electrostatic chuck electrode 60C (or 60a) is made of an electrostatic chuck as described above by turning off the applied voltage. 1/”/ri [160b, 6
The connecting member 31 of the J piezoelectric cord 30 is attached to the receiving part 62 of each support stand 6:3 of 0d and 60a (or 60C) without play. Then, similar to the above, electrostatic chips "Ji poles 60a, 60b, 60c, 60
By controlling d and the voltage applied to the driving piezoelectric element 30 on and off, it moves in the X11 (+) direction according to the amount of expansion and contraction of the driving piezoelectric element 30! 11I'71-ru.

Further, as another embodiment of the present invention, two electrostatic chuck electrodes (for example, Y
axis (if moving in the tenth direction, use the electrostatic chuck electrode 60)
A voltage is applied to the piezoelectric element 64 (a, 60c), and the connecting portion 4431 is
Even if the drive piezoelectric element 30 is supported through the support, it can be moved efficiently and stably in the same manner as described above.

J3, the connecting means is not limited to the connecting member 31 and the receiving part 62 of the stadium, but it is preferable to use something close to point support such as a pot bearing.

[Effects of the Invention] As described above based on the embodiments, according to the present invention, during driving, the first piezoelectric element and the second piezoelectric element are connected to each other via the connecting means to form a gap in the moving direction. Therefore, the expansion and contraction movement of the first piezoelectric element is reliably transmitted to the electrostatic V-tick electrode, allowing efficient and stable micro-movement driving.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the fine movement drive mechanism according to the present invention applied to a scanning tunneling microscope (STM), and FIG.
The plan view of the fine movement drive structure shown in Fig. 1 and Fig. 3 are as follows.
An enlarged schematic diagram of the fine movement drive mechanism shown in FIG. 1 without showing the main parts;
Figure 1 (a>, (b), and (C) are 32 clear diagrams and 5
The figure shows a conventional fine-movement drive mechanism using a scanning tunneling microscope (S
FIG. 6, which is a schematic diagram of the case where the present invention is applied to TM), is a plan view of the fine movement drive structure shown in FIG. 5. 10... Base electrode (base plate) 30... Piezoelectric cord for driving (first piezoelectric element) 31...
・Connection member (connection means) 40...Measurement sample 50...
・Probes 60a, 60b, 60c, 60d--Electrostatic electrode 61...Movement base 62...Receptacle (connection means) 63-
...Support stand 6/I...Piezoelectric cord (second piezoelectric element)
7071...Switch 80.81...Power supply

Claims (2)

[Claims] (1) A base electrode, a plurality of electrostatic chuck electrodes arranged at predetermined positions on the base electrode, and a first piezoelectric material that can be expanded and contracted in a predetermined movement plane in order to move these electrostatic chuck electrodes. a second piezoelectric element attached to each of the electrostatic chuck electrodes and capable of expanding and contracting substantially orthogonally to the direction within the predetermined movement plane; A fine movement drive mechanism comprising: a connection means for transmitting information to an element; and a fine movement drive mechanism. (2) In the fine movement drive mechanism according to claim 1, by applying a voltage to at least two of the second piezoelectric elements, the first and second piezoelectric elements are moved in the moving direction via the connecting means. After the electrostatic chuck electrode corresponding to the second piezoelectric element is connected so that no gap is formed, the electrostatic chuck electrode corresponding to the second piezoelectric element is released from adsorption, and at least one other electrostatic chuck electrode is held in an adsorbed state, the electrostatic chuck electrode is 1. A drive control method for a fine movement drive mechanism, the method comprising driving a piezoelectric element by applying a voltage to the piezoelectric element.