JP5368214B2 - Micro electromechanical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a micro-electro mechanical element with improved symmetry. <P>SOLUTION: Movable electrodes 108, 109 are physically connected by an insulating connecting member 110. Thus, when a drive signal for a first terminal 111 and a second terminal 112 is applied, the movable electrodes 108, 109 are displaced similarly, and therefore improved symmetry can be obtained when compared with a prior art in which two conventional MEMS varactors are simply combined. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a fine electromechanical device having an electrode that moves by applying a voltage.

  In recent years, MEMS (Micro-Electro-Mechanical Systems) technology that performs three-dimensional microfabrication by performing etching and the like using thin film formation technology and photolithography technology has attracted attention, and microelectronics using this MEMS technology Mechanical elements are being developed. As this fine electromechanical element, for example, there is a MEMS varactor composed of a movable electrode and a fixed electrode, which are expected to be applied in a wireless communication circuit or the like (for example, see Non-Patent Document 1). The MEMS varactor will be described with reference to FIGS. 8A to 8C.

  As shown in FIG. 8A, the MEMS varactor 1000 is arranged at a position sandwiching the substrate 1001 made of an electrically insulating member, the fixed electrode 1002 formed on the upper surface of the substrate 1001, and the fixed electrode 1002 on the upper surface of the substrate 1001. A pair of columnar support portions 1003 and 1004 extending vertically upward, a spring portion 1005 having one end supported by the upper end of the support portion 1003 and extending toward the upper end of the support portion 1004, and one end being the support portion 1004. A spring portion 1006 that is supported by the upper end and extends toward the upper end of the support portion 1003, and a movable electrode 1007 that is connected to the other ends of the spring portions 1005 and 1006 and is disposed to face the fixed electrode 1002. Here, a first terminal 1008 is connected to the fixed electrode 1002, and a second terminal 1009 is connected to the support portion 1003 via electric wiring provided on the substrate 1001. Further, the fixed electrode 1002, the support portions 1003 and 1004, the spring portions 1005 and 1006, and the movable electrode 1007 are composed of conductive members. Therefore, the movable electrode 1007 is electrically connected to the second terminal 1009 through the spring portion 1005 and the support portion 1003. In addition, a capacitance is formed between the fixed electrode 1002 and the movable electrode 1007 that are arranged to face each other.

  When a DC voltage is applied between the first terminal 1008 and the second terminal 1009 of the MEMS varactor 1000, the movable electrode 1007 is attracted toward the fixed electrode 1002 by electrostatic attraction as shown in FIG. 8B. Thereby, since the interval between the fixed electrode 1002 and the movable electrode 1007 changes, the capacitance between the fixed electrode 1002 and the movable electrode 1007 also changes. The MEMS varactor is expected to be an important element that supports the realization of next-generation wireless communication circuits because it can achieve high linearity and a high variable rate compared to semiconductor varactors fabricated using conventional semiconductor technology. .

  In a wireless communication circuit using a varactor, it is effective to use a differential circuit in order to reduce the influence of noise and obtain high performance. In the differential circuit, the influence of noise can be canceled by processing a differential signal composed of two voltages or currents having the same amplitude and inverted phases.

  In the MEMS varactor 1000 described above, the second signal (symbol c) is in phase with the first signal (symbol b) shown in FIG. 8C at the second terminal 1009 and the first signal at the first terminal 1008. ), A differential signal (reference numerals b and c) whose phases are shifted from each other by π to a bias signal for displacing the movable electrode 1007 between the first terminal 1008 and the second terminal 1009. It can be used as a varactor for a differential circuit by being superimposed.

  In such a differential circuit, in order to sufficiently exhibit the effect of noise reduction, the circuit is required to have high symmetry. High symmetry means that the processing for the two signals constituting the differential signal is equivalent, and noise can be further reduced by providing high symmetry. In order to realize a differential circuit having high symmetry, it is desirable that the elements constituting the circuit have high symmetry. For example, in a two-terminal element, the characteristics of the element viewed from the first terminal and the characteristics of the element viewed from the second terminal are required to be equal.

M. V. Shakhrai, “Microelectromechanical (MEMS) Varactors for Mobile Communications,” 4th Siberian Russian Workshop and Tutorials EDM’2003, Tutorials, 1-4 July, Erlagol, 2003.

  However, in the conventional microelectromechanical element such as the MEMS varactor 1000 described above, one first terminal 1008 is connected to the fixed electrode 1002, whereas the other second terminal 1009 is provided with the support portion 1003 and the spring. Since it is connected to the movable electrode 1007 via the part 1005, the structure is asymmetric and the symmetry of the element characteristics is low. For this reason, parasitic resistance, parasitic capacitance, parasitic inductance, and the like are distributed asymmetrically, and therefore, the characteristics of the first terminal 1008 and the second terminal 1009 are different from each other, particularly at high frequencies. When such an asymmetric element is applied to a differential circuit, there arises a problem that noise cannot be sufficiently reduced.

In order to solve such a problem, a method conventionally proposed in the field of semiconductor circuits is that two M 's are formed on the same common substrate 101 as in the micro electromechanical element 2000 shown in FIG. The EMS varactor 1000 is provided, and the fixed electrode 1002 of one MEMS varactor 1000 and the support portion 1003 of the other MEMS varactor 1000 are used as a first terminal 1008, and the fixed electrode 1002 of one MEMS varactor 1000 and the other There is a method in which a support unit 1003 of the MEMS varactor 1000 is connected to the second terminal 1009 and two microelectromechanical elements having low symmetry such as the MEMS varactor 1000 described above are combined and handled as one element. is there.

  However, as shown in FIG. 9, when two MEMS varactors 1000 are combined, there is a difference in the shape of the spring of each element, the interval between the fixed electrode 1002 and the movable electrode 1007, etc. due to non-uniformity and variations in manufacturing. Occurs. Due to this influence, a difference occurs in the electrical characteristics and mechanical characteristics of the two elements, so that it becomes difficult to sufficiently increase the symmetry. Moreover, since the two MEMS varactors 1000 are combined, the occupied area is also increased.

  Therefore, an object of the present invention is to provide a fine electromechanical element with improved symmetry.

  In order to solve the problems as described above, the microelectromechanical element according to the present invention is supported in such a manner that the first electrode and the first electrode are movably supported in a direction connecting the first electrode and itself. A first electrode and a second electrode constituting the first capacitive electrode pair, a third electrode electrically connected to the second electrode, and the first electrode Is electrically connected to the third electrode while being supported so as to be movable in a direction connecting the third electrode and the third electrode, and is physically insulated from the second electrode. And at least a third electrode and a fourth electrode constituting the second capacitor electrode pair.

  In the microelectromechanical element, the first capacitor electrode pair and the second capacitor electrode pair have the same area of the electrodes included in each, and the centers of gravity of the electrodes included in the first capacitor electrode pair and the second capacitor electrode pair coincide with each other in plan view. You may do it.

  In the microelectromechanical element, two electrodes constituting at least one of the first capacitive electrode pair and the second capacitive electrode pair are each divided into a plurality of parts, and the second electrode and the fourth electrode are , They may be physically connected.

  In the microelectromechanical element, the fifth electrode is disposed so as to face the fifth electrode in a state of being supported so as to be movable in a direction connecting the fifth electrode and the fifth electrode. The fourth electrode may be physically connected in a state of being electrically insulated from the fourth electrode, and may further include the fifth electrode and a sixth electrode constituting a drive electrode pair.

  In the micro electro mechanical device, the center of gravity of the drive electrode pair may coincide with the center of gravity of the first capacitor electrode pair and the center of gravity of the second capacitor electrode pair in plan view.

  Further, in the micro electro mechanical device, the first electrode and the second electrode are fixed to the upper surface, the conductive supporting portion protruding from the upper surface of the substrate, and one end supported on the upper end of the supporting portion. The other end is connected to the second electrode or the fourth electrode, and the conductive spring portion is provided on the substrate and connected to the second electrode or the fourth electrode via the support portion and the spring portion. The wiring may be further provided.

  According to the present invention, in the microelectromechanical device having two capacitive electrode pairs, the second electrode constituting the first capacitive electrode pair and the fourth electrode constituting the second capacitive electrode pair are: Since it is physically connected in an electrically insulated state, when at least one of the second electrode and the fourth electrode moves, the other moves in conjunction with this movement. The symmetry of can be improved.

FIG. 1A is a plan view schematically showing the configuration of the fine electromechanical device according to the first embodiment of the present invention. 1B is a cross-sectional view taken along line I-I in FIG. 1A. FIG. 1C is a schematic diagram for explaining voltages applied to the fine electromechanical device according to the first embodiment of the present invention. FIG. 2A is a plan view schematically showing a configuration of a fine electromechanical element according to the second embodiment of the present invention. 2B is a cross-sectional view taken along line II-II in FIG. 2A. 2C is a cross-sectional view taken along line III-III in FIG. 2A. FIG. 3A is a cross-sectional view of the main part for explaining the operation of the micro electro mechanical device according to the second embodiment of the present invention. FIG. 3B is a cross-sectional view of the main part for explaining the operation of the micro electro mechanical device according to the second embodiment of the present invention. FIG. 4A is a plan view schematically showing a configuration of a fine electromechanical element according to the third embodiment of the present invention. 4B is a cross-sectional view taken along line IV-IV in FIG. 4A. FIG. 5A is a plan view schematically showing a configuration of a micro electro mechanical device according to the fourth embodiment of the present invention. 5B is a cross-sectional view taken along the line V-V in FIG. 5A. 5C is a cross-sectional view taken along the line VI-VI in FIG. 5A. FIG. 6 is a plan view schematically showing a configuration of a fine electromechanical element according to the fifth embodiment of the present invention. FIG. 7 is a plan view schematically showing a configuration of a fine electromechanical element according to the sixth embodiment of the present invention. FIG. 8A is a side view schematically showing a configuration of a conventional fine electromechanical element. FIG. 8B is a side view schematically showing the operation of the fine electromechanical device of FIG. 8A. FIG. 8C is a schematic diagram for explaining a voltage applied to the fine electromechanical device of FIG. 8A. FIG. 9 is a side view schematically showing the configuration of another conventional microelectromechanical element.

[Shape status of the first embodiment]
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

<Configuration of fine electromechanical element>
As shown in FIGS. 1A and 1B, a microelectromechanical device 1 according to the present embodiment is arranged in parallel with a plate-like substrate 101 and a top surface of the substrate 101 with a predetermined distance therebetween. A pair of fixed electrodes 102 and 103 having a substantially rectangular shape in plan view that act as first and third electrodes and fixed electrodes 102 and 103 on the upper surface of the substrate 101 and arranged in a position sandwiching them from each other and extending vertically upward. Columnar support portions 104, 105, a spring portion 106 having one end supported by the upper end of the support portion 104 and extending toward the upper end of the support portion 105, and one end supported by the upper end of the support portion 105. The spring portion 107 extending toward the upper end of the electrode has a shape equivalent to that of the fixed electrode 102, the other end of the spring portion 106 is connected and disposed opposite to the fixed electrode 102, and functions as the second electrode of the present invention. Movable power 108 and the fixed electrode 103, the other end of the spring portion 107 is connected to the fixed electrode 103, the movable electrode 109 acting as the fourth electrode of the present invention, and the movable electrode 108 An insulating connecting member 110 is provided that connects the opposite side of the side to which the spring part 106 is connected and the opposite side of the movable electrode 109 to which the spring part 107 is connected.
Here, the fixed electrode 102 constituting the first capacitor electrode pair and the support portion 105 constituting a part of the second capacitor electrode pair are connected to the first terminal 111 via the electric wiring provided on the substrate 101. It is connected to the. Similarly, the fixed electrode 103 constituting the second capacitor electrode pair and the support portion 104 constituting a part of the first capacitor electrode pair are connected to the second terminal 112 via the electric wiring provided on the substrate 101. It is connected to the.
In addition, a first capacitor 113 is formed between the fixed electrode 102 and the movable electrode 108 constituting the first capacitor electrode pair. Similarly, a second capacitor 114 is formed between the fixed electrode 103 and the movable electrode 109 constituting the second capacitor electrode pair.

  The substrate 101 is made of, for example, a silicon substrate having an insulating film such as a silicon oxide film formed on the surface thereof, an insulator such as an alumina substrate or a glass substrate, and insulates the fixed electrodes 102 and 103 and the support portions 104 and 105, respectively. Yes.

  The fixed electrodes 102 and 103, the support portions 104 and 105, the spring portions 106 and 107, and the movable electrodes 108 and 109 are made of conductive members such as Au, Al, Cu, and Ni, for example.

  Thus, the support parts 104 and 105, the spring parts 106 and 107, and the movable electrodes 108 and 109 are comprised from the member which has electroconductivity. Therefore, the movable electrode 108 is electrically connected to the first terminal 111 via the spring portion 106 and the support portion 104. Similarly, the movable electrode 109 is electrically connected to the second terminal 112 via the spring portion 107 and the support portion 105.

  The insulating connecting member 110 is made of, for example, an insulating material such as a silicon oxide film or a silicon nitride film, and is physically connected to the movable electrodes 108 and 109 integrally. Such an insulating connecting member 110 desirably acts as a rigid body.

  Such a fine electromechanical device 1 can be manufactured by performing film formation, selective etching, or the like using a known micromachine manufacturing technique.

<Operation of micro electromechanical element>
When a drive signal is applied to the first terminal 111 and the second terminal 112, the microelectromechanical device 1 according to the present embodiment includes a fixed electrode 102 and a movable electrode 108 that form the first capacitor electrode pair. And a potential difference is generated between the fixed electrode 103 and the movable electrode 109 constituting the second capacitor electrode pair, and the movable electrode 108 is moved toward the fixed electrode 102 by electrostatic attraction based on the potential difference. 109 are attracted to the fixed electrode 103 side. At this time, since the movable electrodes 108 and 109 are physically connected by the insulating connecting member 110, the movable electrodes 108 and 109 are displaced integrally (in conjunction with each other). As described above, when the gap between the electrodes of the first capacitor electrode pair or the gap between the electrodes of the second capacitor electrode pair changes, the sizes of the first capacitor 113 and the second capacitor 114 also change. By using this change in capacitance, the fine electromechanical device 1 can be used as a varactor, for example.

  Note that when the fine electromechanical element 1 is used as a varactor, a voltage signal is used as a drive signal. In this case, the upper waveform indicated by symbol b in FIG. 1C is input to the first terminal 111, and the lower waveform indicated by symbol c is input to the second terminal 112, whereby the first terminal 111 and the second waveform are input. A drive signal having a drive bias voltage (symbol a) is applied between the two terminals 112. The signal indicated by symbol b and the signal indicated by symbol c have the same amplitude and are inverted in phase. When such a drive signal is applied, an electrostatic attractive force is generated between the first and second capacitive electrode pairs, and the movable electrodes 108 and 109 are displaced and attracted toward the fixed electrodes 102 and 103 in the direction. . At this time, since the movable electrodes 108 and 109 are physically connected by the insulating connecting member 110, the movable electrodes 108 and 109 are displaced integrally (in conjunction with each other).

As described above, according to the present embodiment, the movable electrodes 108 and 109 are similarly displaced in accordance with the application of the drive signal to the first terminal 111 and the second terminal 112. Symmetry can be improved. That is, the movable electrodes 108 and 109 are physically connected by the insulating connecting member 110, and the movable electrodes 108 and 109 are integrated (in conjunction with each other) in response to the application of the drive signal to the first terminals 111 and 112. ) Because of the displacement, higher symmetry can be obtained as compared with the case where the two MEMS varactors 1000 are simply combined as in the micro electromechanical element 2000 shown in FIG.
Further, microelectromechanical device 1, since the respective fixed electrodes and the movable electrode of the first terminal 111 and second terminal 112 is connected, it is possible to obtain a high symmetry.
Further, since some components such as the spring portions 106 and 107 need not be provided for each capacitive electrode pair, the occupied area can be reduced as compared with the fine electromechanical device 2000 shown in FIG. Can also be realized.

  In the present embodiment, the case where the fine electromechanical element 1 is mainly used as a varactor has been described as an example. However, the use of the fine electromechanical element 1 is not limited to the varactor, and can be applied freely as appropriate. it can. For example, the fine electromechanical element 1 can be applied to an acceleration sensor. In this case, acceleration applied from the external environment is used as a drive signal. By connecting a differential capacitance sensing circuit to the microelectromechanical device 1 and detecting displacement of the movable electrodes 108 and 109 caused by application of acceleration as changes in the first and second capacitances 113 and 114, an acceleration signal is detected. Can be detected. Also in this case, by using the fine electromechanical element 1 having excellent symmetry in combination with a differential capacitance sensing circuit, a high-performance acceleration sensor with reduced influence of noise or the like can be realized.

  In the present embodiment, the fixed electrodes 102 and 103 are disposed on the substrate 101. However, the fixed electrodes 102 and 103 may be configured to be displaceable in the same manner as the movable electrodes 108 and 109.

  In the present embodiment, the case where the first and second capacitor electrode pairs are parallel plate types has been described as an example. However, the configuration of the first and second capacitor electrode pairs is not limited to the parallel plate type. For example, a comb-teeth shape can be applied as appropriate. Further, the displacement direction of the movable electrodes 108 and 109 is not limited to the direction perpendicular to the substrate 101, but may be displaced in the horizontal direction or other directions.

[Shape status of the second embodiment]
Next, a second embodiment according to the present invention will be described. In addition, this Embodiment is corresponded to what arranged two fine electromechanical elements 1 which concern on 1st Embodiment.

  As shown in FIGS. 2A to 2C, the microelectromechanical device 2 according to the present embodiment includes a plate-like substrate 200, fixed electrodes 201 to 204 disposed on the upper surface of the substrate 200, and a front surface of the substrate 200. Provided support portions 211 to 214, spring portions 221 to 224 whose one ends are supported by the upper ends of the support portions 211 to 214, movable electrodes 231 to 234 to which the other ends of the spring portions 221 to 224 are connected, And an insulating connecting member 241 for connecting the movable electrodes 231 to 234. Here, the fixed electrode 201, the support portion 212, the support portion 213, and the fixed electrode 204 are connected to the first terminal 251 through electric wiring provided on the substrate 200. Similarly, the fixed electrode 202, the support portion 211, the fixed electrode 203, and the support portion 214 are connected to the second terminal 252 through electric wiring provided on the substrate 200.

  The substrate 200 is made of, for example, a silicon substrate having an insulating film such as a silicon oxide film formed on the surface thereof, or an insulator such as an alumina substrate or a glass substrate, and insulates the fixed electrodes 201 to 204 and the support portions 211 to 214, respectively. Yes.

The fixed electrode 201 has a substantially rectangular shape in plan view, is disposed on the upper surface of the substrate 200, and functions as a division of the first electrode of the present invention.
The fixed electrode 202 has a shape equivalent to that of the fixed electrode 201, is arranged at a predetermined interval from the fixed electrode 201 in the first direction, and functions as a third electrode of the present invention divided.
The fixed electrode 203 has a shape equivalent to that of the fixed electrode 201, is arranged at a predetermined interval in the second direction with respect to the fixed electrode 201, and functions as a third electrode of the present invention divided.
The fixed electrode 204 has a shape equivalent to that of the fixed electrode 201, and is disposed in the second direction with respect to the fixed electrode 202 and spaced apart from the fixed electrode 203 in the first direction by a predetermined distance. The first electrode of FIG.
Such fixed electrodes 201 to 204 are composed of conductive members such as Au, Al, Cu, and Ni, and are insulated from each other on the substrate 200.

The support portions 211 and 212 have a columnar shape extending vertically upward, and are disposed at positions sandwiching the fixed electrodes 201 and 202 on the upper surface of the substrate 200.
The support portions 213 and 214 have the same shape as the support portions 211 and 212, and are disposed at positions that sandwich the fixed electrodes 203 and 204 on the upper surface of the substrate 200.
Such support parts 211-214 are comprised from the member which has electroconductivity, such as Au, Al, Cu, Ni, for example.

The spring portion 221 has a configuration in which one end is supported by the upper end of the support portion 211 and extends toward the upper end of the support portion 212.
The spring portion 222 has a configuration in which one end is supported by the upper end of the support portion 212 and extends toward the upper end of the support portion 211.
The spring part 223 has a configuration in which one end is supported by the upper end of the support part 213 and extends toward the upper end of the support part 214.
The spring part 224 has a configuration in which one end is supported by the upper end of the support part 214 and extends toward the upper end of the support part 213.
Such spring portions 221 to 224 are made of conductive members such as Au, Al, Cu, and Ni, for example.

The movable electrode 231 has a shape equivalent to that of the fixed electrode 201, is connected to the other end of the spring portion 221 and is disposed so as to face the fixed electrode 201, and acts as a part of the second electrode of the present invention.
The movable electrode 232 has the same shape as the movable electrode 231, is connected to the other end of the spring portion 222, is disposed to face the fixed electrode 202, and acts as a part of the fourth electrode of the present invention.
The movable electrode 233 has the same shape as the movable electrode 231, is connected to the other end of the spring portion 223, is disposed opposite to the fixed electrode 203, and acts as a part of the fourth electrode of the present invention.
The movable electrode 234 has the same shape as the movable electrode 231, is connected to the other end of the spring portion 224, is disposed to face the fixed electrode 204, and acts as a part of the second electrode of the present invention.
Such movable electrodes 231 to 234 are made of conductive members such as Au, Al, Cu, and Ni, for example.

  The insulating connecting member 241 has a substantially cross shape in plan view, and is physically connected to the adjacent movable electrodes 231 to 234 in a state of being separated by a predetermined distance. Such an insulating connecting member 241 is made of, for example, an insulating material such as a silicon oxide film or a silicon nitride film, and desirably functions as a rigid body.

  The microelectromechanical element 2 having such a configuration can be manufactured by performing film formation, selective etching, or the like using a known micromachine manufacturing technique.

  In the microelectromechanical element 2, the fixed electrode 201 and the movable electrode 231 arranged to face each other constitute a first capacitor electrode pair region, and a first capacitor 261 is formed therebetween. Similarly, the fixed electrode 202 and the movable electrode 232, the fixed electrode 203 and the movable electrode 233, and the fixed electrode 204 and the movable electrode 234, which are opposed to each other, constitute second to fourth capacitive electrode pair regions. Between these, second to fourth capacitors 262 to 264 are formed. Of the first to fourth capacitive electrode pair regions, the first and fourth capacitive electrode pair regions constitute a first capacitive electrode pair, and the second and third capacitive electrode pair regions are second. The capacitive electrode pair is configured.

  The first capacitor electrode pair and the second capacitor electrode pair are formed so that the areas of the fixed electrode and the movable electrode of each of them are equal. Further, the first to fourth capacitor electrode pair regions are arranged so that the center of gravity of the first capacitor electrode pair and the center of gravity of the second capacitor electrode pair coincide with each other in plan view.

  The microelectromechanical element 2 having such a configuration is movable with the fixed electrodes constituting the first to fourth capacitive electrode pair regions when a drive signal is applied to the first terminal 251 and the second terminal 252. A potential difference is generated between the electrodes, and the respective movable electrodes are attracted to the fixed electrode side facing each other by electrostatic attraction based on the potential difference. At this time, since the movable electrodes 231 to 234 are physically connected by the insulating connecting member 241, they are displaced integrally (in conjunction with each other). Thus, when the distance between the fixed electrode and the movable electrode in the first to fourth capacitive electrode pair regions changes, the sizes of the first to fourth capacitors 261 to 264 also change. By using this change in capacitance, the fine electromechanical element 2 can be used as a varactor, for example.

  In the present embodiment, each capacitor electrode pair region is arranged so that the centers of gravity of the two capacitor electrode pairs coincide. Thereby, higher symmetry can be obtained. This will be described with reference to FIG.

  Conventionally, in microelectromechanical elements, the phenomenon that the movable electrode tilts due to non-uniformity and variation in manufacturing has occurred. In such a case, the characteristics of the element fluctuate and symmetry Was deteriorated. In the micro electro mechanical device 2 according to the present embodiment, as shown in FIGS. 3A and 3B, when the movable electrode is tilted, as shown in FIG. 3A, the first capacitor 261 in the first capacitor electrode pair region is provided. And the second capacitor 262 in the second capacitor electrode pair region becomes larger, but the fourth capacitor 264 in the fourth capacitor electrode pair region becomes larger and the third capacitor becomes larger as shown in FIG. 3B. The third capacitance 264 in the electrode pair region is reduced. Therefore, the sum of the capacities of the first and fourth capacitor electrode pairs constituting the first capacitor electrode pair is the sum of the capacities of the second and third capacitor electrode pairs constituting the second capacitor electrode pair. Is equal to As a result, the characteristics of the microelectromechanical element 2 viewed from the first terminal 251 and the characteristics of the microelectromechanical element 2 viewed from the second terminal 252 become equal, so that high symmetry is achieved even when an inclination occurs. Can be obtained.

  As described above, according to the present embodiment, the movable electrodes 231 to 234 are physically connected by the insulating connecting member 241 to apply the drive signal to the first terminal 251 and the second terminal 252. Accordingly, since the movable electrodes 231 to 234 are displaced integrally (in conjunction with each other), the symmetry in the fine electromechanical element can be improved.

  In the microelectromechanical element 2 of the present embodiment, the first capacitor electrode pair and the second capacitor electrode pair are divided into a plurality of regions, so that the first capacitor electrode pair and the second capacitor electrode are divided. It is possible to easily match the center of gravity of the pair.

  In the present embodiment, since the first capacitor electrode pair and the second capacitor electrode pair are divided into a plurality of regions, the drive electrodes can be moved in a balanced manner.

Third form status of implementation of]
Next, a third embodiment according to the present invention will be described. The microelectromechanical element 3 according to the present embodiment includes a third capacitive electrode between the first capacitive electrode pair and the second capacitive electrode pair of the microelectromechanical element 1 according to the first embodiment. Corresponds to a pair.

As shown in FIGS. 4A and 4B, the microelectromechanical element 3 according to the present embodiment is arranged on a plate-like substrate 300 and an upper surface of the substrate 300 at a predetermined interval along the first direction. The fixed electrodes 301, 303, and 302 that are substantially planar in plan view, and the fixed electrodes 303 that are in the direction orthogonal to the positions of the fixed electrodes 301, 303, and 302 on the upper surface of the substrate 300 and the arrangement direction of the fixed electrodes 301, 303, and 302 The columnar support portions 311 to 313 are disposed in the vicinity of each other, extend vertically upward, the spring portion 321 is supported at the upper end of the support portion 311 and extends toward the upper end of the support portion 312, and one end is A spring portion 322 supported by the upper end of the support portion 312 and extending toward the upper end of the support portion 311, and a bar having one end supported by the upper end of the support portion 313 and extending toward the fixed electrode 303 in the horizontal plane. A movable electrode 331 having the same shape as the fixed electrode 301 and the other end of the spring portion 321 connected to the other end of the spring portion 321 and a fixed electrode 302 connected to the other end of the spring portion 322 The movable electrode 332 having the same shape as the fixed electrode 302, one end connected to the movable electrode 331 via the insulating connecting member 341, and the other end connected to the movable electrode 332 via the insulating connecting member 342, And a movable electrode 333 having a shape equivalent to that of the fixed electrode 303.
Here, the fixed electrode 301 constituting the first capacitor electrode pair and the support portion 312 constituting a part of the second capacitor electrode pair are connected to the first terminal 351. In addition, the fixed electrode 302 constituting the second capacitor electrode pair and the support portion 311 constituting a part of the first capacitor electrode pair are connected to the second terminal 352. The fixed electrode 303 is connected to the third terminal 353, and the support portion 313 is connected to the fourth terminal 354.

  The substrate 300 is made of an insulator such as a silicon substrate having an insulating film such as a silicon oxide film formed on the surface thereof, an alumina substrate, or a glass substrate, and insulates the fixed electrodes 301 to 303 and the support portions 311 to 313, respectively. Yes.

The fixed electrodes 301 to 303, the support portions 311 to 313, the spring portions 321 to 323, and the movable electrodes 331 to 333 are made of conductive members such as Au, Al, Cu, and Ni, for example.
Here, the fixed electrode 301 functions as the first electrode in the present invention. Further, the fixed electrode 302 functions as a third electrode in the present invention. In addition, the movable electrode 331 functions as the second electrode in the present invention. Moreover, the movable electrode 332 functions as the fourth electrode in the present invention.

  The insulating connecting members 341 and 342 are made of, for example, an insulating material such as a silicon oxide film or a silicon nitride film, and are physically connected to the movable electrodes 331 to 333 integrally. Such insulating connecting members 341 and 342 desirably work as rigid bodies.

  Such a fine electromechanical element 3 can be produced by laminating and processing a film using a known micromachine technique.

  In the microelectromechanical element 3 according to the present embodiment, the fixed electrode 301 and the movable electrode 331 which are arranged to face each other constitute a first capacitor electrode pair, and a first capacitor is formed between them. ing. In addition, the fixed electrode 302 and the movable electrode 332 that are arranged opposite to each other constitute a second capacitor electrode pair, and a second capacitor is formed between them. Further, the fixed electrode 303 and the movable electrode 333 arranged opposite to each other constitute a drive electrode pair.

  In such a microelectromechanical element 3, when a voltage is applied between the third terminal 353 and the fourth terminal 354, an electrostatic attractive force is generated between the fixed electrode 303 and the movable electrode 333 constituting the drive electrode pair. The movable electrode 333 is attracted toward the fixed electrode 303. At this time, since the movable electrodes 331 and 332 are mechanically connected to the movable electrode 333 via the insulating connecting members 341 and 342, the movable electrodes 331 and 332 are integrated with the movement of the movable electrode 333. It moves toward the fixed electrodes 301 and 302 (in conjunction). As a result, the distance between the fixed electrode 301 and the movable electrode 331 and the distance between the fixed electrode 302 and the movable electrode 332 change, so that the magnitudes of the first capacitance and the second capacitance also change.

  In the case of the MEMS varactor 1000 shown in FIGS. 8A and 8B, since there is no drive electrode pair, the AC signal is superimposed on the first terminal 1008 and the second terminal 1009 as shown in FIG. 8C. It is necessary to apply a drive bias voltage. For this reason, a circuit for applying a driving bias voltage must be connected to the first terminal 1008 and the second terminal 1009, and symmetry may be deteriorated due to the influence of this circuit. On the other hand, the microelectromechanical element 3 according to the present embodiment has a drive electrode pair composed of the fixed electrode 303 and the movable electrode 333 in addition to the first and second capacitive electrode pairs. The capacitance can be changed by applying the drive voltage to the drive electrode pair without degrading the performance.

  In the present embodiment, since the three electrode pairs of the first and second capacitor electrode pairs and the drive electrode pair are provided, the drive electrodes can be moved in a balanced manner.

[Fourth Embodiment]
Next, a fourth embodiment according to the present invention will be described.

  As shown in FIGS. 5A to 5C, the microelectromechanical element 4 according to the present embodiment includes a plate-like substrate 400, fixed electrodes 401 to 405 provided on the substrate 400, and a substrate 400. Support portions 411 to 418, spring portions 421 to 428 supported at one ends by the support portions 411 to 418, movable electrodes 431 to 435 arranged to face the fixed electrodes 401 to 405, and insulating connecting members 441 to 441 444. The fixed electrodes 402 and 404 and the support portions 414 and 418 are connected to the first terminal 451. The fixed electrodes 403 and 405 and the support portions 412 and 416 are connected to the second terminal 452. The fixed electrode 401 is connected to the third terminal 453, and the support portion 411 is connected to the fourth terminal 454.

  The substrate 400 is made of, for example, a silicon substrate having an insulating film such as a silicon oxide film formed on its surface, an insulator such as an alumina substrate or a glass substrate, and insulates the fixed electrodes 401 to 405 and the support portions 411 to 418, respectively. Yes.

The fixed electrode 401 has a circular shape and is disposed at a substantially central portion on the upper surface of the substrate 400. On the other hand, each of the fixed electrodes 402 to 405 has a substantially sector shape obtained by dividing a circle concentric with the fixed electrode 401 into four equal parts, and each of the fixed electrodes 402 to 405 is point-symmetric with respect to the center of the fixed electrode 401 around the fixed electrode 401. So as to be spaced apart by a predetermined distance. Here, the fixed electrode 402 acts as a division of the first electrode in the present invention. The fixed electrode 403 acts as a division of the third electrode in the present invention. Further, the fixed electrode 404 functions as a result of dividing the first electrode in the present invention. The fixed electrode 405 acts as a division of the third electrode in the present invention.
Such fixed electrodes 401 to 405 are made of conductive members such as Au, Al, Cu, and Ni, for example.

  The support portions 411 to 418 have a columnar shape extending vertically upward, and are spaced apart from each other by a predetermined distance with respect to the center of the fixed electrode 401 outside the fixed electrodes 402 to 405 on the upper surface of the substrate 400. Be placed. Such support parts 411-318 are comprised from the member which has electroconductivity, such as Au, Al, Cu, Ni, for example.

  One end of each of the spring portions 421 to 428 is supported by the upper ends of the support portions 411 to 418, and extends toward the upper end of the support portion disposed to face the support portions. Such spring parts 421-428 are comprised from the member which has electroconductivity, such as Au, Al, Cu, Ni, for example.

The movable electrode 431 has the same shape as the fixed electrode 401, the other ends of the spring portions 421, 423, 425, and 427 are connected and are disposed to face the fixed electrode 401.
The movable electrode 432 has the same shape as the fixed electrode 402, the other end of the spring portion 422 is connected to the center of the arc, and the periphery of the movable portion 432 except for the arc is the spring portions 421 and 423 by the insulating connecting member 441. In addition, it is connected to the movable electrode 431 and is disposed to face the fixed electrode 402, and acts as a part of the second electrode in the present invention.
The movable electrode 433 has the same shape as that of the fixed electrode 403, the other end of the spring portion 424 is connected to the center of the arc, and the surroundings except for the arc portion are spring portions 423 and 425 around the insulating connecting member 442. In addition, the movable electrode 431 is connected to the fixed electrode 403 so that the fourth electrode in the present invention is divided.
The movable electrode 434 has the same shape as the fixed electrode 404, the other end of the spring portion 426 is connected to the center of the arc, and the periphery of the movable portion 434 except for the arc portion is the spring portions 425 and 427 by the insulating connecting member 443. In addition, it is connected to the movable electrode 431 and is disposed opposite to the fixed electrode 404, and acts as a part of the second electrode in the present invention.
The movable electrode 435 has the same shape as the fixed electrode 405, the other end of the spring portion 428 is connected to the center of the arc, and the surroundings except for the arc portion are spring portions 427 and 421 by the insulating connecting member 444. The movable electrode 431 is connected to the fixed electrode 405 so as to be divided into the fourth electrode in the present invention.
Such movable electrodes 431 to 435 are made of conductive members such as Au, Al, Cu, and Ni, for example.

  The insulating connecting members 441 to 445 are made of an insulating material such as a silicon oxide film or a silicon nitride film, and are physically connected to the movable electrodes 431 to 435 integrally. Such insulating connecting members 441 to 445 desirably work as rigid bodies.

  Such a fine electromechanical element 4 can be produced by performing film formation, selective etching, or the like using a known micromachine manufacturing technique.

In the microelectromechanical device 4 according to the present embodiment, the fixed electrode 402 and the movable electrode 432 that are arranged to face each other constitute a first capacitor electrode pair region, and a first capacitor is formed between them. Has been. Similarly, the fixed electrode 403 and the movable electrode 433, the fixed electrode 404 and the movable electrode 434, and the fixed electrode 405 and the movable electrode 435 that are opposed to each other constitute second to fourth capacitive electrode pair regions. Between these, second to fourth capacitors are formed. Among the first to fourth capacitive electrode pair regions, the first and third capacitive electrode pair regions disposed opposite to each other with the fixed electrode 401 interposed therebetween constitute the first capacitive electrode pair, and the second , The fourth capacitor electrode pair region constitutes a second capacitor electrode pair. Such a first capacitor electrode pair and a second capacitor electrode pair are formed so that the areas of the fixed electrode and the movable electrode of each of them are equal. The first to fourth capacitor electrode pair regions are arranged so that the center of gravity of the first capacitor electrode pair and the center of gravity of the second capacitor electrode pair coincide.
On the other hand, the fixed electrode 401 and the movable electrode 431 arranged opposite to each other constitute a drive electrode pair.

  In such a microelectromechanical element 4, when a voltage is applied between the third terminal 453 and the fourth terminal 454, an electrostatic attractive force is generated between the fixed electrode 401 and the movable electrode 431 constituting the drive electrode pair. The movable electrode 431 is attracted toward the fixed electrode 401. At this time, since the movable electrodes 432 to 445 are mechanically connected to the movable electrode 431 via the insulating connecting members 441 to 444, the movable electrodes 432 to 445 are also connected to the movable electrode 431 as the movable electrode 431 moves. It moves toward the fixed electrodes 402 to 405 together (in conjunction). As a result, the distance between the fixed electrode and the movable electrode in the first to fourth capacitive electrode pair regions changes, and the magnitudes of the first to fourth capacitances also change.

  At this time, in the microelectromechanical element 4 according to the present embodiment, the first capacitor electrode pair and the second capacitor electrode pair are each composed of two capacitor electrode pair regions, as in the second embodiment described above. The capacitive electrode pairs are arranged so that the respective centers of gravity coincide with each other. Thereby, it is possible to prevent a difference between the values of the first capacitor and the second capacitor due to non-uniformity and variations in manufacturing.

  The microelectromechanical element 4 includes a drive electrode pair, and the drive electrode pair is disposed such that the center of gravity thereof coincides with the center of gravity of the first capacitor electrode pair and the second capacitor electrode pair. . As a result, even when the electrodes are displaced by applying a voltage to the drive electrode pair, the first to fourth capacitance changes can be made uniform even if the electrodes are tilted. As a result, the symmetry can be improved.

  In the present embodiment, since the four capacitor electrode pair regions are provided, the drive electrodes can be moved in a well-balanced manner.

  In the present embodiment, the case where the shape of the entire fixed electrode and the movable electrode is circular has been described as an example. However, the shape of the electrode is not limited to a circle, and may be freely set as appropriate, for example, a square or a trapezoid. be able to.

[Fifth Embodiment]
Next, a fifth embodiment according to the present invention will be described.

  As shown in FIG. 6, the microelectromechanical element 5 according to the present embodiment includes a plate-like substrate 500 and a circular fixed electrode that is formed on the upper surface of the substrate 500 and serves as the first electrode in the present invention. 501, a fixed electrode 502 formed around the fixed electrode 501 and acting as a third electrode in the present invention and having a substantially C-shape in plan view, a center of the fixed electrode 501, and a gap between the fixed electrodes 502 A pair of columnar support portions 511 and 512 that are arranged at positions sandwiching the fixed electrodes 501 and 502 on a straight line passing through and vertically extend, and one end is supported by the upper end of the support portion 511 and the upper end of the support portion 512 The spring portion 521 extending toward the upper end, the spring portion 522 having one end supported by the upper end of the support portion 512 and extending toward the upper end of the support portion 511, and a shape equivalent to the fixed electrode 501. The other end of the spring is connected to the fixed electrode 501, and the movable electrode 531 acting as the second electrode in the present invention has the same shape as the fixed electrode 502, and the other end of the spring portion is opposite to the gap. Is connected to the fixed electrode 502 so as to overlap the fixed electrode 502 when viewed from the vertical direction, and acts as the fourth electrode in the present invention, and between the movable electrode 531 and the movable electrode 532 And an insulating connecting member 541 for connecting them. Here, the fixed electrode 501 constituting the first capacitor electrode pair and the support portion 511 constituting a part of the second capacitor electrode pair are connected to the first terminal 551 via the electric wiring provided on the substrate 500. It is connected to the. In addition, the fixed electrode 502 constituting the second capacitor electrode pair and the support portion 512 constituting a part of the first capacitor electrode pair are connected to the second terminal 552 through the electric wiring provided on the substrate 500. It is connected.

  The substrate 500 is made of, for example, a silicon substrate having an insulating film such as a silicon oxide film formed on its surface, an alumina substrate, a glass substrate, or the like, and insulates the fixed electrodes 501 and 502 and the support portions 511 and 512, respectively.

  The fixed electrodes 501 and 502, the support parts 511 and 512, the spring parts 521 and 522, and the movable electrodes 531 and 532 are made of conductive members such as Au, Al, Cu, and Ni, for example.

  The insulating connecting member 541 is made of, for example, an insulating material such as a silicon oxide film or a silicon nitride film, and such an insulating connecting member 541 that is integrally connected to the movable electrodes 531 and 532 is physically connected. It is desirable to act as a rigid body.

  Such a fine electromechanical element 5 can be produced by laminating and processing a film using a known micromachine technique.

  In such a microelectromechanical element 5, the fixed electrode 501 and the movable electrode 531 that are arranged to face each other constitute a first capacitor electrode pair, and a first capacitor is formed between them. Similarly, the fixed electrode 502 and the movable electrode 532 that are arranged opposite to each other constitute a second capacitor electrode pair, and a second capacitor is formed between them.

  The first capacitor electrode pair and the second capacitor electrode pair are formed such that the areas of the fixed electrode and the movable electrode of each of the first capacitor electrode pair and the second capacitor electrode pair are equal, and the centers of gravity when viewed from the vertical direction coincide.

  In such a microelectromechanical element 5, when a voltage is applied between the first terminal 551 and the second terminal 552, between the fixed electrode 501 and the movable electrode 531 constituting the first capacitor electrode pair, and An electrostatic attractive force is generated between the fixed electrode 502 and the movable electrode 532 constituting the second capacitor electrode pair. At this time, since the movable electrode 531 and the movable electrode 532 are physically connected by the insulating connecting member 541, they are displaced together (in conjunction). When the distance between the electrodes of the first capacity electrode pair or the distance between the electrodes of the second capacity electrode pair changes in this way, the respective capacity also changes. By using this change in capacitance, the fine electromechanical element 5 can be used as a varactor, for example.

As described above, according to the present embodiment, the movable electrodes 531 and 532 are physically connected by the insulating connecting member 541 to apply the drive signal to the first terminal 551 and the second terminal 552. Accordingly, the movable electrodes 551 and 552 are similarly displaced, so that the symmetry of the fine electromechanical element can be improved.
Further, in the present embodiment, the capacitive electrode pair is not necessarily divided into a plurality of regions as in the fourth embodiment described above, and the same effect as the fourth embodiment is realized. be able to.

[Sixth Embodiment]
Next, a sixth embodiment according to the present invention will be described. The micro electro mechanical element 6 according to the present embodiment is obtained by connecting the movable electrode 232 and the movable electrode 233 in the micro electro mechanical element 2 according to the second embodiment described above. Therefore, in the present embodiment, the same names and symbols are assigned to the same components as those in the second embodiment, and the description thereof is omitted as appropriate.

  As shown in FIG. 7, the microelectromechanical element 6 according to the present embodiment is provided with a plate-like substrate 200, fixed electrodes 201, 601 and 204 arranged on the upper surface of the substrate 200, and a front surface of the substrate 200. The supported portions 211 to 214, the spring portions 221 to 224 whose one ends are supported by the upper ends of the support portions 211 to 214, and the movable electrodes 231 and 6 # 1, to which the other ends of the spring portions 221 to 224 are connected. 234 and insulating connecting members 641 and 642 for connecting the movable electrodes 231, 631 and 234. Here, the fixed electrode 201, the support portion 212, the support portion 213, and the fixed electrode 204 are connected to the first terminal 251 through electric wiring provided on the substrate 200. Similarly, the fixed electrode 601, the support part 211, and the support part 214 are connected to the second terminal 252 through electrical wiring provided on the substrate 200.

Here, the fixed electrode 601 has a shape in which the fixed electrode 202 in the second embodiment and the adjacent corners of the fixed electrode are connected by a linear member, and acts as the second electrode in the present invention.
The movable electrode 631 has the same shape as the fixed electrode 601 and functions as the fourth electrode in the present invention.

The insulating connecting member 641 has a substantially L shape in plan view, and connects the adjacent movable electrodes 231 and 601 with a predetermined distance therebetween.
The insulating connecting member 642 has a substantially L shape in plan view, and connects the adjacent movable electrodes 234 and 601 with a predetermined distance therebetween.
Therefore, the insulating connection members 641 and 642 are integrated with the movable electrodes 231, 234, and 601 to physically connect them. Such insulating connection members 641 and 642 desirably work as rigid bodies.

In such a microelectromechanical element 6, the fixed electrode 201 and the movable electrode 231 arranged to face each other constitute a first capacitor electrode pair region, and a first capacitor is formed between them. . The fixed electrode 204 and the movable electrode 234 constitute a second capacitor electrode pair region, and a second capacitor is formed between them. These first and second capacitor electrode pair regions constitute a first capacitor electrode pair.
On the other hand, the fixed electrode 601 and the movable electrode 631 arranged opposite to each other constitute a drive electrode pair and a second capacitor electrode pair. A third capacitor is formed between them.

  Here, the first capacitor electrode pair and the second capacitor electrode pair are formed so that the areas of the fixed electrode and the movable electrode of each of them are equal. The first to fourth capacitor electrode pair regions are arranged so that the center of gravity of the first capacitor electrode pair and the center of gravity of the second capacitor electrode pair coincide.

  When the drive signal is applied to the first terminal 251 and the second terminal 252, the microelectromechanical element 6 having such a configuration is movable with the fixed electrode constituting the first to third capacitor electrode pair regions. A potential difference is generated between the electrodes, and the respective movable electrodes are attracted to the fixed electrode side facing each other by electrostatic attraction based on the potential difference. At this time, since the movable electrodes 231, 631, and 234 are physically connected by the insulating connection members 641 and 642, they are displaced in conjunction with each other. Thus, when the distance between the fixed electrode and the movable electrode included in the first and second capacitor electrode pairs changes, the magnitudes of the first to third capacitors also change. By using this change in capacitance, the fine electromechanical element 6 can be used as a varactor, for example.

As described above, according to this embodiment, the movable electrodes 231, 631, and 234 are physically connected by the insulating connection members 641 and 642, thereby driving the first terminal 251 and the second terminal 252. Since the movable electrodes 231, 631, and 234 are similarly displaced in response to the application of the signal, the symmetry of the fine electromechanical element can be improved.
In the present embodiment, even if the above-described configuration is adopted, the same operational effects as those of the second embodiment can be obtained. Therefore, when there are a plurality of capacitive electrode pairs, the fixed electrode and the movable electrode that constitute the capacitive electrode pair region of each capacitive electrode pair may not be divided for each capacitive electrode pair region.

  The present invention can be applied to various fine electromechanical elements using MEMS technology such as a MEMS varactor.

  DESCRIPTION OF SYMBOLS 1-6 ... Fine electromechanical element, 101 ... Board | substrate, 102, 103 ... Fixed electrode, 104, 105 ... Support part, 106, 107 ... Spring part, 108, 109 ... Movable electrode, 110 ... Insulation connection member, 111, 112 DESCRIPTION OF SYMBOLS Terminal, 113 ... 1st capacity | capacitance, 114 ... 2nd capacity | capacitance, 200 ... Board | substrate, 201-204 ... Fixed electrode, 211,212 ... Support part, 221-224 ... Spring part, 231-234 ... Movable electrode, 241 ... Insulating connecting member, 251 ... first terminal, 252 ... second terminal, 261 to 264 ... first to fourth capacitors, 300 ... substrate, 301 to 303 ... fixed electrode, 311 to 313 ... support part, 321 323 ... Spring portion, 331 to 333 ... movable electrode, 341 and 342 ... insulating connecting members, 351 to 354 ... first to fourth terminals, 400 ... substrate, 401 to 405 ... fixed electrode, 411 to 418 Support portions, 421 to 428 ... spring portions, 431 to 435 ... movable electrodes, 441 to 444 ... insulating connecting members, 451 to 454 ... first to fourth terminals, 500 ... substrate, 501 502 ... fixed electrodes, 511 DESCRIPTION OF SYMBOLS 512 ... Support part, 521, 522 ... Spring part, 531, 532 ... Movable electrode, 541 ... Insulating connection member, 551 ... First terminal, 552 ... Second terminal, 601 ... Fixed electrode, 631 ... Movable electrode.

Claims (5)

A first electrode;
A first electrode and a second electrode constituting a first capacitive electrode pair, arranged opposite to the first electrode in a state of being supported so as to be movable in a direction connecting the first electrode and itself; ,
A third electrode electrically connected to the second electrode;
The second electrode is electrically connected to the first electrode and is opposed to the third electrode in a state of being supported so as to be movable in a direction connecting the third electrode and itself. A third electrode and a fourth electrode constituting a second capacitor electrode pair, and physically connected in an insulated state to each other ,
The first capacitor electrode pair and the second capacitor electrode pair are characterized in that the areas of the electrodes included in each of the first capacitor electrode pair and the second capacitor electrode pair are equal to each other, and the centers of gravity of the electrodes included in each of them are identical in plan view. Fine electromechanical element. In claim 1 Symbol placement of microelectromechanical devices,
Two electrodes constituting at least one of the first capacitive electrode pair and the second capacitive electrode pair are each divided into a plurality of parts,
The second electrode and the fourth electrode, the fine pore electromechanical devices characterized in that it is physically connected. The fine electromechanical device according to claim 1 or 2 ,
A fifth electrode;
In a state of being supported so as to be movable in a direction connecting the fifth electrode and itself and being opposed to the fifth electrode, and being electrically insulated from the second electrode and the fourth electrode A microelectromechanical device, further comprising: a sixth electrode that is physically connected and that constitutes the fifth electrode and a drive electrode pair. The fine electromechanical device according to claim 3 ,
The fine electromechanical device, wherein the center of gravity of the drive electrode pair coincides with the center of gravity of the first capacitor electrode pair and the center of gravity of the second capacitor electrode pair in plan view. The fine electromechanical device according to any one of claims 1 to 4 ,
A substrate having the first electrode and the second electrode fixed to an upper surface;
A conductive support projecting from the top surface of the substrate;
One end is supported by the upper end of the support portion, and the other end is connected to the second electrode or the fourth electrode, and a conductive spring portion,
And a wiring connected to the second electrode or the fourth electrode via the support portion and the spring portion.

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