JP3132165B2 - Micro actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microactuator manufactured by an IC manufacturing method such as etching or lithography.

[0002]

2. Description of the Related Art As a conventional microactuator, for example, a paper by Mehregany et al.
abricated harmonic and ordinary side-drive motor
s ", in Proceedings of the third IEEE Workshop on Mi
cro Electro Mechanical Systems, Napa Valley, Califo
rnia, USA, February 11-14, 1990, pp. 1-8.).

FIG. 12 is a plan view schematically showing the structure of this conventional electrostatic micro wobble motor, and FIG.
2 shows a cross-sectional view of the same electrostatic micro wobble motor.

12 and 13, reference numeral 1 denotes a bearing, 2 denotes a rotor having an outer diameter of about 100 μm, and 3a to 3h
Are eight electrodes provided circumferentially around the rotor 2 (twelve electrodes are seen in the photograph of the motor introduced in the paper). Although not shown, these electrodes 3a to 3h are each provided with a wiring from a power supply, and a voltage can be arbitrarily selected and applied.

[0005] As shown in the figure, the rotor 2 has an annular shape, and a clearance C is provided between the inner periphery thereof and the bearing 1.
Is provided, unlike a normal motor, the rotor 2 is not supported by the bearing 1 to rotate. That is, with the application of the voltage to the electrodes 3a to 3h, the rotor 2 revolves while being sequentially attracted to the excited electrodes 3a to 3h.

However, at the same time, the rotor 2 and the bearing 1 move while rolling and contacting each other at the contact 2a, so that the rotor 2 rotates by the difference between the outer circumference of the bearing 1 and the inner circumference of the rotor 2. This operation will be described later in detail.

The rotor 2 is supported by the flange 1a of the bearing 1 so as not to come off the bearing 1. The electrodes 3a to 3h (only 3a and 3e are shown in the figure) and the rotor 2 have substantially the same height, but a plurality of protrusions provided on the lower surface of the rotor 2 instead of being annular. 2b, which is configured to slide on the shield layer 4 to obtain electrical contact.

FIGS. 14 to 18 show a process (a) for manufacturing the electrostatic micro wobble motor described below.
FIGS. 5A to 5E are diagrams illustrating a general IC manufacturing method such as etching and lithography. Hereinafter, the manufacturing method will be briefly described according to the process chart.

(A) On a silicon substrate 5, a 1 μm thick oxide film thermally grown and a 1 μm thick oxide film deposited by LPCVD
The insulating layer 6 is formed by stacking a thick silicon nitride layer.

On top of this, 350 which has sufficiently diffused phosphorus is used.
An LPCVD polycrystalline silicon thin film having a thickness of 0 ° is formed and patterned to form an electric shield layer 4.

Further, a low-temperature oxide (LTO) film 7 having a thickness of 2.2 μm serving as a first sacrificial layer is deposited, and patterning is performed for the fixing portion 7a of the electrodes 3a to 3h and the concave portion 7b for forming the projection 2b of the rotor 2. Is performed in two stages.

(B) 2.5 μm in which phosphorus is sufficiently diffused
Deposit a thick LPCVD polysilicon layer and use reactive ion etching (RIE)
And the electrodes 3a to 3h (only 3a and 3e are shown) as shown in FIG. As shown, the electrodes 3a to 3h are fixed on the silicon substrate 5, and the rotor 2 has a plurality of protrusions 2b.

Since a patterned thermal oxide film is used as a mask for RIE of the polycrystalline silicon layer,
At this stage, the thickness of the rotor 2 and the electrodes 3a to 3h is 2.2 μm.
m.

(C) An LTO film 8 serving as a second sacrificial layer having a thickness of about 0.3 μm is deposited, a clearance C between the bearing 1 and the rotor 2 is secured, and the fixing portion 8a of the bearing 1 is patterned. In addition, this bearing 1
Has a diameter of about 36 μm, but the minimum value is set to 26 μm due to process restrictions.

(D) A 1 μm-thick LPCVD polycrystalline silicon layer in which phosphorus is sufficiently diffused is deposited, and a flange 1 a
Is formed.

(E) LTO as first and second sacrificial layers
The structures shown in FIG. 13 are completed by dissolving the membranes 7 and 8 with buffered hydrofluoric acid (HF) and completely releasing the rotor 2.

The operation of the conventional electrostatic micro wobble motor configured as described above will be described below with reference to FIG.
Rather than being pivotally supported by the bearing 1, it revolves while being sequentially attracted to the excited electrodes 3 a to 3 h, and at the same time makes rolling contact with the contact 2 a while contacting the outer periphery of the bearing 1 and the inner periphery of the rotor 2. It rotates by the amount of the difference.

That is, assuming that the electrode 3a is sequentially excited in the X direction in the figure, such as the electrode 3a, then the electrode 3b, and the electrode 3c, first, as shown in the figure, the rotor 2 is attracted to the excited electrode 3a. It is in the state that was done. Then, it is sucked by the excited electrode 3b, and then sucked by the electrode 3c, so that the rotor 2 revolves in the X direction in the drawing.

Since the clearance C between the rotor 2 and the bearing 1 is set smaller than the gap G between the rotor 2 and the electrodes 3a to 3h, the rotor 2 comes into contact with the bearing 1 to form a contact 2a. Note that the gap between the rotor 2 and the electrodes 3a to 3h correctly corresponds to G + E in the figure, but this E means the effective gap length that generates the torque of the motor, and E = G from the motor configuration. −C> 0 (this is apparent if the state where the electrode 3e is excited is assumed). Since the value of the effective gap length E is set to be as small as possible, it is treated as G as a gap between the rotor 2 and the electrodes 3a to 3h for convenience.

When the rotor 2 revolves in the X direction, the contact 2a also moves in the X direction. At this time, since the bearing 1 is fixed, if the rotor 2 does not rotate, the portion of the contact 2a does not rotate. As a result, slippage occurs due to the difference between the outer circumference of the bearing 1 and the inner circumference of the rotor 2. However, a suction force acts on the rotor 2 in the direction of pressing the bearing 1, and practically, almost no sliding occurs at the contact 2a.

Accordingly, as the rotor 2 revolves in the same direction as the rotation direction (X direction) of the voltage applied to the electrodes 3a to 3h, the outer periphery of the bearing 1 and the inner part of the rotor 2 in the same direction (Y direction in the drawing). It will rotate by an amount corresponding to the difference in circumference. Of course, the contact 2a moves in the X direction while making rolling contact.

The feature of this electrostatic micro wobble motor is that the rotation frequency of the rotation of the rotor 2 is determined by the outer diameter B of the bearing 1 and the inner diameter R of the rotor 2, and the rotation frequency of the input voltage is smaller than that of a normal motor. F (in this example, the physical rotation frequency of the voltage applied to the electrodes 3a to 3h)
In contrast, the rotation frequency S of the rotation of the rotor 2 is significantly reduced.

When the rotation frequency of the revolution of the rotor 2 is equal to the rotation frequency F of the input voltage, the rotation frequency S of the rotation of the rotor 2 is represented by S = F × (RB) / R = F × C / R. And the number of revolutions is S / F,
That is, since the torque is C / R, the torque is increased by R / C times. In addition, by reducing the clearance C, it is possible to eliminate slippage at the contact 2a and to suppress swinging of the rotor 2 due to revolution.

As a result, a low-speed and high-torque motor can be constructed without using a deceleration means or the like, and it is highly expected that the motor can be used as a drive source of a micromachine.

[0025]

However, in the above structure, the protrusions on the lower surface of the rotor and the shield layer or the flange are constantly in contact with the rotor during the rotation of the rotor. Wear occurs,
The life of the motor will be significantly shortened. Further, since the protrusion on the lower surface of the rotor slides on the shield layer to obtain electrical contact, reliable conduction between the rotor and the shield layer cannot be stably obtained, and the reliability of the motor characteristics is reduced. Low. Moreover, the characteristics of the motor depend on the outer diameter of the bearing,
Since the inner and outer diameters of the rotor and the inner diameter of the electrode all depend on the dimensional accuracy, there has been a problem that it is difficult to obtain reliable rotational accuracy.

In view of the foregoing, it is an object of the present invention to provide a long-life and highly reliable microactuator which can be manufactured by an IC manufacturing method, can be freely designed, and can be positioned with high accuracy.

[0027]

According to a first aspect of the present invention, there is provided a microactuator comprising: a plurality of electrodes circumferentially arranged on a substrate; and a ring-shaped moving plate located inside the electrodes. And a beam that elastically supports the moving plate and has a fixed end on the substrate inside the moving plate, and selectively applies a voltage to the electrode to electrostatically attract the moving plate to the electrode , And a voltage applying means for revolving and rotating .

According to a seventh aspect of the present invention, there is provided a microactuator comprising: a plurality of electrodes circumferentially arranged on a substrate;
A ring-shaped moving plate located inside these electrodes, the beam having a fixed end on the substrate the moving plate inside the elastic support and the mobile plate, by controlling the voltage applied to the electrode A drive control circuit for controlling the rotation of the moving plate, a signal detection unit for converting an external signal into an electric signal, and a signal processing circuit for processing the electric signal and sending a control signal to the drive control circuit; A plurality of units are manufactured in an array on the same substrate as one unit.

[0029]

According to the first aspect of the present invention, a voltage is selectively applied to a plurality of electrodes circumferentially arranged on a substrate, and a ring-shaped moving plate located inside these electrodes is electrostatically charged. Suction and revolve and rotate At this time, the movable plate is elastically supported by the beam having a fixed end on the substrate. Since the electrical contact of the movable plate that is electrostatically driven is reliably obtained through the beam, the reliability of the drive characteristics of the movable plate is improved. Further, since the contact between the rotating moving plate and the electrode becomes rolling contact, the influence of friction is extremely reduced, and a long-life microactuator can be obtained. Further, since the rotation accuracy of the moving plate is determined only by the roundness of the electrode and the moving plate, accuracy control in the manufacturing process is easier than in the conventional example. Furthermore, since the moving plate is supported by the beam and moves while elastically deforming the beam, if the excitation of the electrode is released, the moving plate easily returns to the initial position by the restoring force of the beam, and the rotational motion is again performed from there. You can get started. Therefore, the position and angle of the moving plate can be controlled with high accuracy and high reproducibility, and an excellent positioning mechanism can be realized. Further, the high torque characteristic inherent in the wobble motor can of course be utilized. In addition, since each element is configured in a plane, the characteristics of the actuator are not affected by the thickness of the sacrificial layer, and a free design that aims at the optimum shape such as the diameter of each part, the number of electrodes, the shape of the beam, etc. And a microactuator that can be easily manufactured by an IC manufacturing method can provide a microactuator that is reduced in size and weight and has high mass productivity.

According to the seventh aspect of the present invention, an external signal is converted into an electric signal by a signal detecting section, processed by a signal processing circuit, sent to a drive control circuit as a control signal, and applied to an electrode. The driving of the ring-shaped moving plate located inside the circumferential electrode is controlled by controlling the voltage, as in the first embodiment. The present invention is a microactuator in which these are further formed into one unit, and a plurality of units are manufactured in an array on the same substrate. Therefore, by integrating the signal detection unit and the signal processing unit into the actuator and making it intelligent, a very compact and highly responsive microactuator can be obtained, and dispersion or coordination by parallel drive control of multiple actuators is obtained. An operable microactuator can be realized.

[0031]

1 is a plan view schematically showing the structure of a microactuator according to a first embodiment of the present invention, and FIG. 2 is a sectional view of the microactuator.

1 and 2, reference numeral 10 denotes an anchor,
1a to 11c are spiral beams, 12 is a ring-shaped moving plate,
Reference numerals 13a to 13p denote 16 electrodes provided circumferentially around the movable plate 12. These electrodes 13a to 13
Although not shown in the figure as in the conventional example, wiring is made for each of the p by voltage applying means, and a voltage can be arbitrarily selected and applied.

As shown by diagonal lines in the figure, the moving plate 12 is a ring-shaped flat plate having an outer diameter of about 100 μm and an inner diameter of about 75 μm, and has three beams 11 a of the same shape arranged on the inner periphery thereof at intervals of about 120 degrees. 11c, it is supported by an anchor 10 having an outer diameter of about 15 μm provided concentrically with the electrodes 13a to 13p. These beams 11a to 11c have a spiral shape with a width of about several μm, and are arranged symmetrically with respect to the centers of the circumferential electrodes 13a to 13p.

The electrodes 13a to 13p (13a, 13i in the figure)
Only shown) is several μm larger than the outer diameter of the moving plate 12.
m is set to be large. Further, the height of the movable plate 1 is slightly lower than that of the movable plate 1 when the electrode is excited.
2 is sucked downward so that stable driving can be performed.

The movable plate 12 is configured to always obtain electrical conduction with the shield layer 14 via the beams 11a to 11c and the anchor 10. The electrode 13
An insulating film 15 is provided on the inner periphery of the moving plates 1 to 13p.
2 so as not to make direct electrical contact.

FIGS. 3 to 7 are views showing the steps (a) to (e) of manufacturing the microactuator, which will be described below. A general IC manufacturing method such as etching or lithography is used for manufacturing. Used. Hereinafter, the manufacturing method will be briefly described according to the process chart.

(A) On a silicon substrate 16, a 1 μm thick oxide film thermally grown and a 1 μm thick
The insulating layer 1 is formed by stacking an m-thick silicon nitride layer.
7 is formed.

On top of this, 350 is obtained by sufficiently diffusing phosphorus.
An LPCVD polycrystalline silicon thin film having a thickness of 0 ° is formed and patterned to form an electric shield layer 14.

(B) A low-temperature oxide (LTO) film 18 having a thickness of 2.2 μm serving as a sacrificial layer is deposited, and is patterned for a fixing portion 18 a of the electrodes 13 a to 13 p and a concave portion 18 b for forming the anchor 10 of the moving plate 12. Perform

(C) 2.5 μm in which phosphorus is sufficiently diffused
A thick LPCVD polycrystalline silicon layer is deposited and, using reactive ion etching (RIE), the moving plate 12, electrodes 13a to 13p shown in FIGS.
3i), the beams 11a to 11c and the anchor 10 are formed. At this time, the electrodes 13 a to 13 p and the anchor 10 are fixed on the silicon substrate 16.

Since a patterned thermal oxide film is used as a mask for RIE of the polycrystalline silicon layer,
At this stage, the moving plate 12, the beams 11a to 11c, and the electrode 1
The thickness of 3a to 13p is about 2.2 μm.

The inner diameters of the electrodes 13a to 13p are set to be larger by the amount of the insulating film 15 formed in a later step.

(D) A thermal oxide film having a thickness of 0.1 μm and a silicon nitride layer having a thickness of 0.34 μm are deposited thereon.
Patterning is performed so that the insulating film 15 is formed on the inner periphery of a to 13p. At this stage, the outer diameter of the moving plate 12 and the electrode 13
a to 13p clearance can be obtained.

(E) Finally, the LTO film 18 as the sacrificial layer is dissolved with buffered hydrofluoric acid (HF), and the movable plate 12 and the beams 11a to 11a are dissolved.
By releasing 11c, the configuration as shown in FIG. 2 is completed.

The operation of the microactuator of this embodiment having the above-described configuration will be described below with reference to FIGS.

As shown in FIG. 8, when the electrode 13a is first excited, the movable plate 12 is electrostatically attracted and the electrode 13a
It contacts the inner peripheral insulating film 15.

Subsequently, as shown in FIG.
With the application of the voltage to 3p, the movable plate 12 revolves in the arrow X direction while being sequentially attracted to the excited electrodes 13a to 13p.

However, at the same time, the moving plate 12 and the electrodes 13a-
The moving plate 13 rotates by the difference between the inner periphery of the electrodes 13a to 13p and the outer periphery of the moving plate 12 because the 13p and the contact portion move while rolling. At this time, the direction of rotation of the movable plate 12 is the direction of the arrow Y opposite to the direction of its revolution.

Here, the moving plate 12 is fixed on the substrate 16 via the beams 11a to 11c and the anchor 10, but the width of the beams 11a to 11c is reduced and a certain length is secured by a spiral shape. As a result, beams 11a to 11
c can be elastically deformed to allow the movable plate 12 to rotate by an angle within a predetermined range.

On the contrary, during the operation of the movable plate 12, the electrode 13a
When the excitation of ~ 13p is released, the elastically deformed beams 11a ~
The movable plate 12 can be easily returned to the initial position by the restoring force of 11c.

The present embodiment is different from the conventional example in that the moving plate 12 which is attracted by the excited electrodes 13a to 13p and revolves and rotates is connected to the anchor 10 by a plurality of spiral beams 11a to 11c and elastically supported. And moving plate 12
Is set so as to be in contact with the electrodes 13a to 13p via the insulating film 15 at the outer periphery thereof.

Accordingly, the rotating moving plate 12 and the electrode 1 are rotated.
The contact with 3a to 13p is only rolling contact, and the influence of friction is extremely small. Therefore, deterioration of drive characteristics due to wear is reduced, and a long-life microactuator can be obtained.

The movable plate 12 which is electrostatically driven has a beam 11
Since it is integrated with the shield layer 14 through a to 11c and the anchor 10 and its electrical contact is reliably obtained, the reliability of the driving characteristics can be improved.

Further, the rotation accuracy of the moving plate 12 is
Not the gap between 3a-13p and the moving plate 12,
Since it is determined only by the roundness of the inner circumference of the electrodes 13a to 13p and the outer circumference of the movable plate 12, accuracy control in the manufacturing process is easier than in the conventional example. Further, only by releasing the excitation of the electrodes 13a to 13p, the movable plate 12 can be easily returned to the initial position by the restoring force of the beams 11a to 11c. Therefore, since the position and angle of the movable plate 12 can be controlled with high accuracy and high reproducibility, the movable plate 12 can be used as a positioning actuator.

Further, according to the microactuator of this embodiment, it is possible to make use of the characteristic of the wobble motor, which is inherently high in torque.

The rotation frequency of the movable plate 12 is
Since it is determined by the inner diameter A of 3p and the outer diameter D of the movable plate 12, the rotation frequency F of the input voltage (in this embodiment, the electrodes 13a to 13p
This is because the rotation frequency Q of the rotation of the movable plate 12 becomes significantly smaller than the physical rotation frequency of the voltage applied to the movable plate 12).

When the rotation frequency of the revolution of the moving plate 12 is equal to the rotation frequency F of the input voltage, the rotation frequency Q of the rotation of the moving plate 12 is represented by Q = F × (A−D) / D.

For example, if the difference between the inner diameter of the electrodes 13a to 13p and the outer diameter (about 100 μm) of the moving plate 12 is 2 μm, the rotation frequency of the moving plate 12 is about 1/50 of the input voltage.
And slow down. However, since the generated torque is inversely proportional to the ratio of the rotation frequency, about 50 times higher torque can be obtained as compared with a case where a normal motor rotating around an axis is electrostatically driven.

As described above, according to this embodiment, there is almost no influence of friction as compared with the prior art, and electrical contact during electrostatic driving is ensured, and a long-life and highly reliable microactuator can be obtained.

Further, accuracy control in the manufacturing process of the moving plate is facilitated, the moving plate can be initialized by the restoring force of the elastically deformed beam, and a highly accurate and highly reproducible positioning mechanism can be realized.

Of course, a high torque similar to that of a wobble motor can be obtained. Furthermore, since each element is configured in a plane, the driving characteristics are not affected by the thickness of the sacrificial layer,
Since a free optimization design is possible and it can be easily manufactured by an IC manufacturing method, it is possible to provide a microactuator that is reduced in size and weight and maintains mass productivity.

If the above-described microactuator is used, for example, by forming a magnetic head finely worked on a moving plate, it is possible to obtain an integrated head capable of both fine positioning and azimuth adjustment. it can. Further, if a semiconductor laser, a hologram element, or the like is configured, a wide range of use values can be obtained as various pickups and optical devices.

Hereinafter, a configuration of a microactuator according to a second embodiment of the present invention will be briefly described with reference to the drawings.

FIG. 10 shows a plan view of the microactuator. The difference from the first embodiment is that the microactuator is formed on the same substrate together with the drive control circuit, the signal processing circuit, and the signal detection unit.

The structure and the manufacturing method of the actuator section 21 composed of a ring-shaped moving plate and a circumferential electrode surrounded by a dashed line in the figure are the same as those of the first embodiment, and therefore description thereof is omitted here. The signal detection unit 22 includes, for example, a photodiode, and converts an optical signal input from the outside in a non-contact manner into an electric signal.

The signal processing section 23 comprises a signal processing circuit and a drive control circuit. The signal processing section 23 processes the electric signal from the signal detection section 22 by this signal processing circuit, and applies the signal to each electrode of the actuator section 21 through the drive control circuit. ON / OFF of the rotation of the movable plate 12 by controlling the magnitude and timing of the applied voltage
And the rotation speed, rotation direction, rotation angle, and the like.

The signal processing section 23 is electrically connected to an external power supply (not shown), and energy for actually driving the movable plate 12 is supplied from the external power supply via the signal processing section 23. Is done. Note that the signal detection unit 22 and the signal processing unit 23 are IC
As shown in FIG. 10, it is formed in a region of about 300 μm square using the manufacturing method.

As shown in FIG. 11, a plurality of these can be integrated into an array on the same substrate as one unit. For example, if 8 × 8 chips are integrated in a matrix, 64 × 8 on a substrate of about 2.5 mm square.
A system having three actuators can be realized.

As described above, by integrating the signal detection section 22 and the signal processing section 23 into the actuator section 21 and making them intelligent, a very compact and highly responsive microactuator can be obtained. Further, by arranging a plurality of these actuators and performing parallel drive control, a microactuator capable of distributed or cooperative operation can be realized.

Here, an example has been described in which the signal detection unit 22 is formed of a photodiode and an optical signal is converted into an electric signal. However, the signal is not limited to light as long as it is a signal input from the outside in a non-contact manner.

The systemized microactuator is expected to be widely applied to optical computers, various recording devices, displays, and the like. If various devices are configured on the moving plate as described above, information can be input and output while data is processed in the unit, so that an extremely high-performance integrated device is created.

[0072]

According to the structure of the present invention, it is possible to provide a microactuator which can be manufactured by an IC manufacturing method and can be freely designed, has a long life and has high reliability, and its industrial value is extremely large. .

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a configuration of a first embodiment of a microactuator according to the present invention.

FIG. 2 is a sectional view of the embodiment.

FIG. 3 is a manufacturing process diagram of the embodiment.

FIG. 4 is a manufacturing process diagram of the embodiment.

FIG. 5 is a manufacturing process diagram of the embodiment.

FIG. 6 is a manufacturing process diagram of the embodiment.

FIG. 7 is a manufacturing process diagram of the embodiment.

FIG. 8 is an operation explanatory diagram of the embodiment.

FIG. 9 is a diagram illustrating the operation of the embodiment.

FIG. 10 is a plan view schematically showing the configuration of a second embodiment of the microactuator of the present invention.

FIG. 11 is a plan view when the embodiment is arranged in an array.

FIG. 12 is a plan view schematically showing a configuration of a conventional electrostatic micro wobble motor.

FIG. 13 is a sectional view of the conventional example.

FIG. 14 is a manufacturing process diagram of the conventional example.

FIG. 15 is a manufacturing process diagram of the conventional example.

FIG. 16 is a manufacturing process diagram of the conventional example.

FIG. 17 is a manufacturing process diagram of the conventional example.

FIG. 18 is a manufacturing process diagram of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Anchor 11a-11c Beam 12 Moving plate 13a-13p Electrode 15 Insulating film

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-190572 (JP, A) JP-A-2-277012 (JP, A) JP-A 2-277011 (JP, A) JP-A-4- 156508 (JP, A) JP-A-4-49878 (JP, A) JP-A-3-203579 (JP, A) JP-A-3-230780 (JP, A) JP-A-4-46575 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H02N 11/00

Claims (7)

(57) [Claims] A plurality of electrodes circumferentially arranged on a substrate;
A ring-shaped moving plate located inside these electrodes, a beam elastically supporting the moving plate and having a fixed end on the substrate inside the moving plate, and selectively applying a voltage to the electrodes. The moving plate is electrostatically attracted to the electrode and revolves.
And a voltage application unit for rotating the micro actuator. Wherein beams of a plurality and the same shape, the micro-actuator according to claim 1, wherein the arranged point symmetric with respect to the center of the circumferential electrodes. 3. The microactuator according to claim 1, wherein the beam has a spiral shape. 4. An apparatus according to claim 1, wherein an insulating film is formed on an outer periphery of the moving plate or an inner periphery of the electrode, and the moving plate and the electrode are in contact with each other via the insulating film. Micro actuator. 5. The microactuator according to claim 1, wherein a shield layer having at least a substantially same shape as the movable plate is provided between the fixed end of the beam and the substrate, facing the movable plate. 6. The apparatus according to claim 1, wherein the voltage applying means comprises a power supply and a drive control circuit for controlling a voltage applied to the electrodes, and at least the drive control circuit is manufactured on the same substrate as the electrodes. Micro actuator. 7. A plurality of electrodes circumferentially arranged on a substrate,
A ring-shaped moving plate located inside these electrodes, the beam having a fixed end on the substrate the moving plate inside the elastic support and the mobile plate, by controlling the voltage applied to the electrode A control circuit for controlling the rotation of the moving plate, a signal detection unit for converting an external signal into an electric signal, and a signal processing circuit for processing the electric signal and sending a control signal to the drive control circuit; A microactuator, wherein a plurality of units are manufactured in an array on the same substrate as a unit.