WO2009113344A1 - Variable capacitance element - Google Patents

Variable capacitance element Download PDF

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Publication number
WO2009113344A1
WO2009113344A1 PCT/JP2009/051972 JP2009051972W WO2009113344A1 WO 2009113344 A1 WO2009113344 A1 WO 2009113344A1 JP 2009051972 W JP2009051972 W JP 2009051972W WO 2009113344 A1 WO2009113344 A1 WO 2009113344A1
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WIPO (PCT)
Prior art keywords
substrate
electrode
movable electrode
hole
fixed electrode
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PCT/JP2009/051972
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French (fr)
Japanese (ja)
Inventor
義宏 小中
光治 竹村
悌二 山本
順一 吉田
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株式会社 村田製作所
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Publication of WO2009113344A1 publication Critical patent/WO2009113344A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G5/00—Capacitors in which the capacitance is varied by mechanical means, e.g. by turning a shaft; Processes of their manufacture
    • H01G5/16—Capacitors in which the capacitance is varied by mechanical means, e.g. by turning a shaft; Processes of their manufacture using variation of distance between electrodes

Definitions

  • the present invention relates to a variable capacitance element that can be varied in capacitance, for example, applied to various electric circuits.
  • FIG. 9a and FIG. 9b are cross-sectional views showing a proposed example of a micro electromechanical switch as a variable capacitance element (see, for example, Patent Document 1).
  • a signal line (wiring) 48 and a bottom electrode 44 are provided on the substrate 42.
  • a movable electrode portion 47 is provided on the substrate 42 via an anchor structure portion 49.
  • the movable electrode portion 47 has spring-like portions on both ends, and is disposed with a distance from the substrate 42.
  • the movable electrode portion 47, the bottom electrode 44, the signal line 48, and the like are manufactured on the substrate 42 by using a thin film forming technique.
  • variable capacitance element shown in FIGS. 9a and 9b forms the wiring by using the thin film formation technique as described above, the loss in the wiring becomes large, and it is difficult to achieve high Q. There's a problem.
  • variable capacitance element as shown in FIGS. 9a and 9b has a problem that self-actuation occurs when a high-power signal is input to the signal line 48.
  • FIG. The reason is that the direction in which the movable electrode portion 47 is displaced when a voltage is applied to the movable electrode portion 47 is a direction approaching the signal line 48, and when a signal is input to the signal line 48, this signal This is because the direction in which the movable electrode portion 47 is displaced by the generated electrostatic force is also a direction approaching the signal line 48. That is, when a high-power signal is input to the signal line 48, the variable capacitance element is drawn to the signal line 48 side by the electrostatic force without applying a voltage to the movable electrode portion 47, It will be displaced.
  • variable capacitance element needs to have the configuration shown in FIGS. 9a and 9b in the package. Therefore, there is a problem that a loss occurs in the sealing portion between this package and the configuration shown in FIGS. 9a and 9b, and the cost is increased because the package forming process is complicated.
  • the present invention has the following configuration. That is, according to the present invention, the insulating first substrate and the insulating second substrate are arranged with the substrate surfaces facing each other with a space therebetween, and the first substrate is arranged in the thickness direction of the substrate. A first through hole penetrating through the second substrate and a second through hole penetrating in the thickness direction of the substrate are formed in the second substrate, and the first and second through holes are filled with a conductor, respectively.
  • a fixed electrode is formed on the surface of the counter substrate of the first substrate and is electrically connected to the conductor filled in the first through hole; and on the surface of the counter substrate of the second substrate, A movable electrode is formed in the conductor filled in the second through-hole through the beam portion, and the movable substrate is urged toward the fixed electrode by the beam portion.
  • the movable electrode and the second substrate are arranged with a space therebetween in a state of floating from the second substrate.
  • At least one of the fixed electrodes is provided with an insulator on the surface facing the counterpart electrode, and the second substrate is provided with a drive electrode that draws and moves the movable electrode toward the second substrate.
  • Means for solving the problem is configured such that a signal conduction path through the capacitor portion between the movable electrode and the fixed electrode is formed by a path passing through the conductor filled in the first through hole.
  • the insulating first substrate and the insulating second substrate are arranged with the substrate surfaces facing each other with a space therebetween, and the first substrate is arranged in the thickness direction of the substrate.
  • a first through-hole and a second through-hole penetrating are formed, and the first and second through-holes are filled with a conductor, respectively, on the surface of the counter substrate of the first substrate.
  • a movable electrode is formed on the opposite substrate surface of the substrate through a beam portion, and the movable electrode is urged toward the fixed electrode side by the beam portion and floats from the second substrate.
  • the second substrate is disposed at an interval, and at least one of the movable electrode and the fixed electrode
  • An insulator is provided on the surface facing the counterpart electrode, and a driving electrode is formed on the second substrate to move the movable electrode toward the second substrate, and a voltage is applied to the driving electrode.
  • the movable electrode is pressed against the first and second fixed electrodes through the insulator, and when a voltage is applied to the drive electrode, the movable electrode moves to the second substrate side.
  • the capacitance between the fixed electrode and the movable electrode is changed by moving in a direction away from the first and second fixed electrodes, and the conductor filled in the first through hole
  • the signal conduction path is formed by the path It is characterized.
  • the insulating first substrate and the insulating second substrate are disposed with their substrate surfaces facing each other with a gap therebetween.
  • the movable electrode is formed on the counter substrate surface of the second substrate via a beam portion.
  • the movable electrode is pressed against the fixed electrode formed on the counter substrate surface of the first substrate when no voltage is applied to the drive electrode.
  • the movable electrode moves toward the second substrate and moves away from the fixed electrode when a voltage is applied to the drive electrode.
  • the present invention when a voltage is applied to the signal conduction path, an electrostatic force is generated in a direction attracting each other between the fixed electrode and the movable electrode.
  • the displacement direction of the movable electrode is opposite. Therefore, in the present invention, even if a high-power signal is input to the signal conduction path, self-actuation can be prevented from occurring due to the influence.
  • a voltage is applied to the drive electrode and the movable electrode is separated from the fixed electrode, the electrostatic force generated between the movable electrode and the fixed electrode is sufficiently small, and the movable electrode is moved toward the second substrate side. Does not affect movement.
  • the signal conduction path is a path having a conductor filled in a through hole formed in the substrate. Therefore, the thickness of the wiring can be increased as compared with the conventional case where the wiring is formed in a substrate shape using a thin film forming technique. Therefore, ESR (Equivalent Series Resistance) of wiring can be reduced, and high Q can be achieved.
  • the fixed electrode, the movable electrode, and the drive electrode are provided in a region sandwiched between the first and second substrates having insulation properties. Therefore, for example, when these electrodes are formed, a fixed frame, a movable electrode, and a drive electrode are sealed by the sealing frame by forming a sealing frame on the outer edge portions of the opposing surfaces of the first and second substrates. it can. This eliminates the need for a package formation step, and thus makes it possible to form the variable capacitance element at a low cost.
  • FIG. 1 is an explanatory cross-sectional view showing a main configuration of a first embodiment of a variable capacitance element according to the present invention. It is a perspective explanatory view showing the appearance composition of the 1st example. It is a typical perspective view which shows the movable part of the variable capacitance element of 1st Example. It is typical sectional drawing for demonstrating the manufacturing process by the side of the 1st board
  • variable capacitance element of 1st Example it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with a different material.
  • variable capacitance element of 1st Example it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with a different material.
  • variable capacitance element of 1st Example it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with the same material.
  • FIG. 6 is an explanatory cross-sectional view showing the main configuration of a second embodiment of the variable capacitance element according to the present invention. It is a figure for demonstrating the external electrode of 2nd Example. In the example of the conventional variable capacitance element, it is a section explanatory view showing the state of switch off.
  • FIG. 9B is a cross-sectional explanatory diagram illustrating a switch-on state of the variable capacitance element of FIG.
  • FIG. 1 shows a first embodiment of a variable capacitance element according to the present invention by a cross-sectional view taken along line AA of FIG.
  • FIG. 1 is a schematic cross-sectional view, omitting the external electrodes 21, 22, and 23 shown in FIG.
  • an insulating first substrate 1 and an insulating second substrate 2 are arranged with their substrate surfaces 11 and 12 facing each other with a gap therebetween.
  • the first and second substrates 1 and 2 are both glass substrates.
  • Each of the first and second substrates 1 and 2 has a thickness of, for example, 300 ⁇ m.
  • the first substrate 1 has one first through hole (via hole (VH)) 3 penetrating in the thickness direction of the substrate.
  • the first through hole 3 is formed at a position corresponding to the signal output portion 33 (see FIG. 2) provided on the external electrode 21 side.
  • the second substrate 2 has four second through holes (via holes) 4 penetrating in the thickness direction of the substrate.
  • VH via hole
  • first and second through holes 3 and 4 are filled with copper (Cu) 13 and 14 as conductors, respectively.
  • a copper fixed electrode 5 that is electrically connected to the copper 13 filled in the first through hole 3 is formed.
  • the fixed electrode 5 is formed to a thickness of 5 ⁇ m.
  • a stopper 10 as an insulator is provided on the front surface side (the lower surface side in this figure) of the fixed electrode 5.
  • the stopper 10 is formed of a silicon oxide (SiO 2 ) film provided on the surface side of the fixed electrode 5.
  • a sealing frame 15 having substantially the same height (thickness) as the fixed electrode 5 is formed on the outer peripheral side thereof.
  • a gold film 17 for sealing is formed on the front end side of the sealing frame 15 with a thickness of about 0.5 ⁇ m.
  • a movable electrode 7 is formed which is electrically connected to the copper 14 filled in the second through hole 4 via the beam portion 6.
  • the movable electrode 7 is arranged to be spaced from the second substrate 2 while being lifted from the second substrate 2 while being urged to the fixed electrode 5 side by the beam portion 6.
  • the fixed electrode 5, the movable electrode 7 and the beam portion 6 are all made of copper having a thickness of about 10 ⁇ m.
  • the movable electrode 7 is in contact with the fixed electrode 5 through the stopper 10 to form a capacitor (capacitor).
  • a stress applying portion 8 having a thickness of 1 ⁇ m for applying a tensile stress in the lifting direction from the second substrate 2 to the beam portion 6 is formed.
  • FIG. 3 shows a schematic perspective view of the movable electrode 7 and the beam portion 6.
  • the movable electrode 7 and the beam portion 6 shown in the cross-sectional view of FIG. 1 show the BB cross section of FIG.
  • a plurality of through holes 27 functioning as damping holes are formed in the movable electrode 7.
  • a drive electrode 9 that moves the movable electrode 7 toward the second substrate 2 is formed of platinum (Pt).
  • An insulating film 19 made of silicon oxide is formed on the surface of the drive electrode 9.
  • a sealing frame 16 having substantially the same height as the movable electrode 7 is formed on the outer peripheral side of the counter substrate surface 12 of the second substrate 2.
  • a gold film 18 for sealing is formed with a thickness of about 0.5 ⁇ m. The gold film 18 and the gold film 17 are joined.
  • External electrodes 23 for driving the drive electrodes 9 (see FIG. 2) are formed on the outer peripheral sides of the gold films 17 and 18 and the sealing frames 15 and 16.
  • symbol 29 shown in FIG. 1 is the contact
  • the movable electrode 7 and the movable electrode 7 are fixed by a path passing through the copper 14 filled in the second through hole 4, the beam portion 6, and the copper 13 filled in the first through hole 3.
  • a signal conduction path is formed through the capacitor between the electrodes 5.
  • an RF (Radio Frequency) signal input external electrode 22 is formed on the surface of the second substrate 2 opposite to the counter substrate surface 12.
  • an external electrode 21 for RF signal output is formed on the surface of the first substrate 1 opposite to the counter substrate surface 11.
  • a signal lead-out portion 33 of the external electrode 21 is connected to the copper 13 in the first through hole 13, and a signal introduction portion 34 of the external electrode 22 is connected to the copper 14 in the second through hole 14.
  • the movable electrode 7 when no voltage is applied to the drive electrode 9, the movable electrode 7 is pressed against the fixed electrode 5 via the stopper 10, as shown in FIG. In this state, the distance between the fixed electrode 5 and the movable electrode 7 is narrow, and this distance is equal to the film thickness of the stopper 10. Therefore, the capacity of the fixed electrode 5 and the movable electrode is large.
  • the movable electrode 7 moves toward the second substrate 2 and moves away from the fixed electrode 5.
  • the distance between the fixed electrode 5 and the movable electrode 7 increases as the thickness of the gold films 17 and 18 changes, and the capacitance between the fixed electrode 5 and the movable electrode 7 decreases.
  • the capacitance between the fixed electrode 5 and the movable electrode 7 changes by turning on and off the voltage of the drive electrode 9.
  • a present Example is formed according to the arrow of a figure by the process as shown in FIG. 4, FIG.
  • a first through hole 3 is formed, and the first through hole 3 is filled with copper 13.
  • the fixed electrode 5 and the sealing frame 15 are formed on the opposing substrate surface 11 of the first substrate 1 by selective plating of copper, and by CMP (Chemical Mechanical Polishing). Surface polishing is performed.
  • Reference numeral 30 denotes a resist for selective plating.
  • the stopper 10 is formed on the surface (the lower surface in this figure) side of the fixed electrode 5, and the gold is formed on the tip side (the lower side in this figure) of the sealing frame 15. A film 17 is formed. Further, the selective plating resist 30 is removed.
  • the second through holes 4 are also formed on the second substrate 2 side, and each second through hole 4 is filled with copper 14.
  • the drive electrode 9, the adhesion layer 29, and the insulating film 19 for preventing the drive unit short circuit are formed on the counter substrate surface 12 of the second substrate 2.
  • the sacrificial layer 24 is formed, and the movable electrode 7, the beam portion 6, and the sealing frame 16 are formed on the upper side of the sacrificial layer 24 by selective copper plating.
  • Reference numeral 31 denotes a resist for selective plating.
  • the selective plating resist 31 is removed and the gold film 18 is formed on the front end side (the upper side in this figure) of the sealing frame 16. Further, a stress applying portion 8 is formed on the surface of the beam portion 6.
  • the stress applying portion 8 can be formed of, for example, a film that applies a stress that pulls the beam portion 6 due to an internal stress of platinum (platinum) or gold. When the stress applying portion 8 is formed simultaneously with the formation of the gold film 18, the variable capacitance element can be manufactured efficiently.
  • the sacrificial layer 24 is removed by etching, and the beam application part 6 is lifted and lifted by the stress applying part 8, and the movable electrode 7 is lifted from the second substrate 2. State.
  • the first substrate 1 and the second substrate 2 are opposed to each other, and the gold film 17 and the gold film 18 are bonded.
  • the fixed electrode 5, the movable electrode 7, the beam portion 6, and the drive electrode 9 are sealed in the space between the first substrate 1 and the second substrate 2, and the movable electrode 7 is The portion 6 is pressed against the fixed electrode 5 side.
  • external electrodes 21, 22, and 23 are formed and cut by dicing to form variable capacitance elements.
  • the present embodiment is manufactured as described above, and has signal conduction paths having copper 13 and 14 filled in the through holes 3 and 4 of the first and second substrates 1 and 2. Therefore, these thicknesses can be increased. For this reason, the present embodiment can reduce the wiring loss and increase the Q. Further, as described above, the displacement direction of the movable electrode 7 by the voltage application to the drive electrode 9 and the signal conduction path of the high-frequency signal. Since the direction of the electrostatic force generated when a voltage is applied to is reversed, self-actuation can be prevented.
  • the sealing frames 15 and 16 can be formed when the fixed electrode 5 is formed and when the drive electrode 7 and the beam portion 6 are formed. And since the fixed electrode 5, the movable electrode 7, and the drive electrode 9 can be sealed in the space sandwiched between the sealing frames 15 and 16 and the first and second substrates 1 and 2, the package forming step can be performed. This is unnecessary, can prevent loss at the package forming portion, and can form the variable capacitance element at low cost.
  • the movable electrode 7 and the beam portion 6 are made of copper, and the resistance of copper is low, so that ESR can be further reduced.
  • the stress applying portion 8 can be formed of the same material as the beam portion 6.
  • a copper film as the stress applying portion 8 is formed on the surface of the beam portion 6 at a high temperature (for example, 80 ° C.). Form.
  • the copper film on the second substrate 2 (the copper film for forming the beam portion 6, the movable electrode 7 and the like) is also raised to the same temperature, so that thermal expansion is attempted.
  • the copper film on the second substrate 2 cannot be expanded because it is integrated with the second substrate 2 which is a glass substrate.
  • the copper film formed at a high temperature is formed in a state of thermal expansion from the low temperature corresponding to the film formation temperature. Therefore, the film for the stress applying portion formed at a high temperature is thermally contracted when the temperature is lowered after the film formation, and when the sacrificial layer 24 is removed, the stress applying portion 8 applies a tensile stress to the beam portion 6.
  • stress can be applied in the direction in which the movable electrode 7 is lifted.
  • a 1 ⁇ m copper stress applying portion 8 is provided for a 10 ⁇ m beam portion 6 and the movable electrode 7 can be lifted by about 8 ⁇ m.
  • the stress applying portion 8 is formed of copper as described above, the following effects can be obtained. That is, when the stress applying portion 8 is formed of gold, platinum, or the like, which is a material different from copper forming the beam portion 6, the beam according to the temperature change due to the difference in linear expansion coefficient between the beam portion 6 and the stress applying portion 8. The warping of the portion 6 changes as shown by the broken lines in FIGS. 6a and 6b. Then, the movable electrode 7 provided on the distal end side of the beam portion 6 moves up and down as shown by the arrow in FIG. 6b, and the force pressing the movable electrode 7 toward the fixed electrode 5 side by the beam portion 6 varies depending on the temperature. End up.
  • the stress applying portion 8 when the stress applying portion 8 is formed of the same material as the copper forming the beam portion 6, the linear expansion coefficient of the beam portion 6 and the stress applying portion 8 is equal. Therefore, the beam portion 6 does not go up and down. Therefore, there is an advantage that the force pressing the movable electrode 7 toward the fixed electrode 5 by the beam portion 6 can be made constant regardless of the temperature. In other words, even when a temperature change occurs, a change in the force that urges the movable electrode 7 toward the fixed electrode 5 by the beam portion 6 hardly occurs. Therefore, the temperature dependence of the capacitance between the fixed electrode 5 and the movable electrode 7 can be reduced. Therefore, when the stress applying portion 8 is formed of the same material as the copper forming the beam portion 6, the applied voltage when the same operation is performed in a wide temperature range by the variable capacitance element can be reduced.
  • variable capacitance element Refers to the description of the second embodiment, parts having the same names as those in the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted or simplified.
  • FIG. 7 is a schematic cross-sectional view showing the variable capacitance element of the second embodiment.
  • a first through-hole 3 and a second through-hole 4 that penetrate in the thickness direction of the substrate are formed in the first substrate 1.
  • These first and second through holes 3 and 4 are filled with copper 13 and 14, respectively.
  • the RF signal output external electrode 22 and the RF signal input external electrode 21 are spaced from each other on the surface 38 opposite to the counter substrate surface 11 of the first substrate 1. Is provided. Further, a signal introducing unit 34 and a signal deriving unit 33 are provided. Further, on the outer peripheral side of the sealing frames 15 and 17, an external electrode 23 for driving the drive electrode 9 is provided (not shown) as in the first embodiment.
  • the external electrode 23 is provided on the surface opposite to the counter substrate surface 11 of the first substrate 1 as shown by a broken line in FIG. 8, and the drive electrode 9 is shown as a broken line A in FIG. It is also possible to conduct to the external electrode 23 from the first substrate 1 side.
  • the copper 13 filled in the first through-hole 3 is conducted to the signal introducing portion 33, and the copper 14 filled in the second through-hole 4 is conducted to the signal deriving portion 34. Further, the counter substrate surface 11 of the first substrate 1 is filled in the first fixed electrode 5 (5a) conducting to the copper 13 filled in the first through hole 3 and the second through hole 4. A second fixed electrode 5 (5b) that is electrically connected to the formed copper 14 is formed. A movable electrode 7 is formed on the counter substrate surface 12 of the second substrate 2 via a beam portion 6.
  • the movable electrode 7 when no voltage is applied to the drive electrode 9, the movable electrode 7 is pressed against the first and second fixed electrodes 5a and 5b via the stopper 10. On the other hand, when a voltage is applied to the drive electrode 9, the movable electrode 7 moves to the second substrate side 2 and moves away from the first and second fixed electrodes 5a and 5b. By such an operation of the movable electrode 7, the capacitance between the fixed electrode 5 and the movable electrode 7 changes.
  • the copper 13 filled in the first through-hole 3, the capacitor between the movable electrode 7 and the first fixed electrode 5a, and the movable electrode 7 and the second fixed electrode 5b are used.
  • a signal conduction path is formed by a path passing through the capacitor portion between the first through hole 4 and the copper 14 filled in the second through hole 4.
  • the capacitor (capacitor) between the movable electrode 7 and the first fixed electrode 5a and the capacitor between the movable electrode 7 and the second fixed electrode 5b are connected in series. It is made.
  • the second embodiment is the same as those of the first embodiment.
  • the first and second through holes 3 and 4 are formed and the copper 13 and 14 filled in the through holes 3 and 4 are connected to the first and second through holes.
  • Second fixed electrodes 5a and 5b are formed.
  • the second embodiment is manufactured in the same manner as the first embodiment. Further, as described above, the second embodiment operates in substantially the same manner as the first embodiment, and can achieve the same effects as the first embodiment.
  • the present invention is not limited to the above-described embodiments, and various embodiments can be adopted.
  • the formation pattern of the movable electrode 7, the beam portion 6 and the like is not limited to the pattern shown in FIG. 3, and is appropriately set.
  • the conductors filling the movable electrode 7, the beam portion 6, and the first and second through holes 3 and 4 are all made of copper, these are not necessarily copper. That is, conductors such as silver (Ag) and gold (Au) other than copper can be appropriately filled in the first and second through holes 3 and 4.
  • the drive electrode 9 is also formed of a suitable conductor.
  • the first and second substrates 1 and 2 are both glass substrates.
  • the first and second substrates 1 and 2 may be insulating substrates made of other insulating materials such as ceramic, alumina, silicon, and gallium arsenide (GaAs).
  • an insulating substrate formed by coating the surface of a conductive material with an insulating material may be used.
  • the stopper 10 which is an insulator is provided on the surface side of the fixed electrode 5.
  • the insulator may be provided on the surface side of the movable electrode 7 (surface facing the fixed electrode), or may be provided on the surface facing the counterpart electrode in both the fixed electrode 5 and the movable electrode 7. .
  • variable capacitance element By providing a configuration unique to the present invention, high Q is possible, self-actuation does not occur at the time of signal input, and an inexpensive variable capacitance element can be formed, so that it can be applied to various electric circuits as a switch or the like. It is possible.

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Abstract

Insulating first and second substrates (1, 2) having through-holes (3, 4) in which copper (13, 14) is filled are disposed so that the respective substrate surfaces face each other with a space in-between. A fixed electrode (5) conducted to the copper (13) is formed on the facing substrate surface (11) of the first substrate (1). An insulating stopper (10) is provided on the surface of the fixed electrode (5). A movable electrode (7) conducted through a beam portion (6) to the copper (14) is formed on the facing substrate surface (12) of the second substrate (2). The movable electrode (7) is spring-biased by the beam portion (6) toward the fixed electrode (5) and is floated from the second substrate (2). When a voltage is not applied to a driving electrode (9), the distance between the fixed electrode (5) and the movable electrode (7) narrows. When the voltage is applied, the movable electrode (7) moves toward the second substrate (2), widening the distance between the fixed electrode (5) and the movable electrode (7). This distance change causes the change of capacitance. A signal conduction path passing through this capacitance portion is formed by the path passing the copper (13, 14).

Description

可変容量素子Variable capacitance element
　本発明は、例えば各種の電気回路に適用される、静電容量の可変が可能な可変容量素子に関するものである。 The present invention relates to a variable capacitance element that can be varied in capacitance, for example, applied to various electric circuits.
　図９ａ、図９ｂは、可変容量素子としての、マイクロ・エレクトロメカニカル・スイッチの提案例を示す断面図である（例えば、特許文献１、参照）。図９ａに示すように、基板４２上には、信号ライン（配線）４８と底部電極４４とが設けられている。また、基板４２上には、アンカ構造部４９を介して、可動電極部４７が設けられている。該可動電極部４７は、両端側にバネ状部位を有し、基板４２と間隔を介して配置されている。可動電極部４７、底部電極４４、信号ライン４８等は、基板４２上に、薄膜形成技術を用いて作製されている。 FIG. 9a and FIG. 9b are cross-sectional views showing a proposed example of a micro electromechanical switch as a variable capacitance element (see, for example, Patent Document 1). As shown in FIG. 9 a, a signal line (wiring) 48 and a bottom electrode 44 are provided on the substrate 42. Further, a movable electrode portion 47 is provided on the substrate 42 via an anchor structure portion 49. The movable electrode portion 47 has spring-like portions on both ends, and is disposed with a distance from the substrate 42. The movable electrode portion 47, the bottom electrode 44, the signal line 48, and the like are manufactured on the substrate 42 by using a thin film forming technique.
　図９ａに示す状態において、可動電極部４７の中央部は、信号ライン４８から離れている。この状態において、可動電極部４７と信号ライン４８との間の容量は小さく、スイッチオフの状態と成している。それに対し、可動電極部４７に電圧を印加すると、図９ｂに示すように、可動電極部４７が静電力で底部電極４４の方に引き寄せられる。そして、可動電極部４７の中央部が信号ライン４８に近づいて、可動電極部４７と配線ライン４８との間の容量が大きくなり、スイッチオンの状態となる。 In the state shown in FIG. 9 a, the central portion of the movable electrode portion 47 is separated from the signal line 48. In this state, the capacitance between the movable electrode portion 47 and the signal line 48 is small, and the switch is turned off. On the other hand, when a voltage is applied to the movable electrode portion 47, the movable electrode portion 47 is attracted toward the bottom electrode 44 by electrostatic force as shown in FIG. 9b. And the center part of the movable electrode part 47 approaches the signal line 48, the capacity | capacitance between the movable electrode part 47 and the wiring line 48 becomes large, and it will be in a switch-on state.
特開２００１－１４３５９５号公報JP 2001-143595 A
　しかしながら、図９ａ、図９ｂに示した可変容量素子は、前記のように、薄膜形成技術を用いて配線を形成しているので、配線でのロスが大きくなり、高Ｑ化が困難であるという問題がある。 However, since the variable capacitance element shown in FIGS. 9a and 9b forms the wiring by using the thin film formation technique as described above, the loss in the wiring becomes large, and it is difficult to achieve high Q. There's a problem.
　また、図９ａ、図９ｂに示したような可変容量素子は、信号ライン４８に大電力の信号を入力すると、セルフアクチュエーションが発生してしまうといった問題もあった。その理由は、可動電極部４７に電圧を印加したときに可動電極部４７が変位する方向が、信号ライン４８に近づく方向であり、かつ、信号ライン４８に信号を入力したときに、この信号によって発生する静電力により可動電極部４７が変位する方向も、信号ライン４８に近づく方向であることによる。つまり、この可変容量素子は、信号ライン４８に大電力の信号を入力すると、可動電極部４７に電圧を印加しなくても、可動電極部４７が静電力により信号ライン４８側に引き寄せられて、変位してしまうのである。 Also, the variable capacitance element as shown in FIGS. 9a and 9b has a problem that self-actuation occurs when a high-power signal is input to the signal line 48. FIG. The reason is that the direction in which the movable electrode portion 47 is displaced when a voltage is applied to the movable electrode portion 47 is a direction approaching the signal line 48, and when a signal is input to the signal line 48, this signal This is because the direction in which the movable electrode portion 47 is displaced by the generated electrostatic force is also a direction approaching the signal line 48. That is, when a high-power signal is input to the signal line 48, the variable capacitance element is drawn to the signal line 48 side by the electrostatic force without applying a voltage to the movable electrode portion 47, It will be displaced.
　さらに、前記可変容量素子は、図９ａ、図９ｂに示した構成を、パッケージ内に設ける必要がある。そのため、このパッケージと図９ａ、図９ｂに示した構成との封止部で、ロスが発生したり、パッケージ形成工程が複雑になるために、コストが高くなってしまったりするといった問題もある。 Furthermore, the variable capacitance element needs to have the configuration shown in FIGS. 9a and 9b in the package. Therefore, there is a problem that a loss occurs in the sealing portion between this package and the configuration shown in FIGS. 9a and 9b, and the cost is increased because the package forming process is complicated.
　上記したような問題点を解決するために、本発明は、次に示す構成を有して構成されている。すなわち、本発明は、絶縁性の第１の基板と絶縁性の第２の基板とが互いに間隔を介して互いに基板面を対向させて配置され、前記第１の基板には基板の厚み方向に貫通する第１の貫通孔が、前記第２の基板には基板の厚み方向に貫通する第２の貫通孔がそれぞれ形成されて、これら第１と第２の貫通孔にはそれぞれ導電体が充填されており、前記第１の基板の前記対向基板面には前記第１の貫通孔に充填された導電体と導通する固定電極が形成され、前記第２の基板の前記対向基板面には前記第２の貫通孔に充填された導電体に梁部を介して導通する可動電極が形成されて、該可動電極は前記梁部によって前記固定電極側に付勢された状態で前記第２の基板から浮いた状態で該第２の基板と間隔を介して配置されており、前記可動電極と前記固定電極の少なくとも一方には相手側電極との対向面に絶縁体が設けられ、前記第２の基板には前記可動電極を前記第２の基板側に引き寄せて移動させる駆動電極が形成されており、該駆動電極に電圧を印加していないときには前記可動電極が前記絶縁体を介して前記固定電極に押しつけられ、前記駆動電極に電圧を印加したときには前記可動電極が前記第２の基板側に移動して前記固定電極から離れる方向に移動することにより前記固定電極と前記可動電極との間の容量が変化する構成と成し、前記第２の貫通孔に充填された導電体と前記梁部と前記第１の貫通孔に充填された導電体を通る経路によって前記可動電極と前記固定電極の間の容量部を介しての信号導通経路が形成されている構成をもって課題を解決する手段としている。 In order to solve the problems as described above, the present invention has the following configuration. That is, according to the present invention, the insulating first substrate and the insulating second substrate are arranged with the substrate surfaces facing each other with a space therebetween, and the first substrate is arranged in the thickness direction of the substrate. A first through hole penetrating through the second substrate and a second through hole penetrating in the thickness direction of the substrate are formed in the second substrate, and the first and second through holes are filled with a conductor, respectively. A fixed electrode is formed on the surface of the counter substrate of the first substrate and is electrically connected to the conductor filled in the first through hole; and on the surface of the counter substrate of the second substrate, A movable electrode is formed in the conductor filled in the second through-hole through the beam portion, and the movable substrate is urged toward the fixed electrode by the beam portion. The movable electrode and the second substrate are arranged with a space therebetween in a state of floating from the second substrate. At least one of the fixed electrodes is provided with an insulator on the surface facing the counterpart electrode, and the second substrate is provided with a drive electrode that draws and moves the movable electrode toward the second substrate. When the voltage is not applied to the drive electrode, the movable electrode is pressed against the fixed electrode through the insulator, and when the voltage is applied to the drive electrode, the movable electrode moves to the second substrate side. The capacitance between the fixed electrode and the movable electrode is changed by moving in a direction away from the fixed electrode, and the conductor filled in the second through hole, the beam portion, Means for solving the problem is configured such that a signal conduction path through the capacitor portion between the movable electrode and the fixed electrode is formed by a path passing through the conductor filled in the first through hole.
　また、本発明は、絶縁性の第１の基板と絶縁性の第２の基板とが互いに間隔を介して互いに基板面を対向させて配置され、前記第１の基板には基板の厚み方向に貫通する第１の貫通孔と第２の貫通孔とが形成されて、これら第１と第２の貫通孔にはそれぞれ導電体が充填されており、前記第１の基板の前記対向基板面には前記第１の貫通孔に充填された導電体に導通する第１の固定電極と前記第２の貫通孔に充填された導電体に導通する第２の固定電極とが形成され、前記第２の基板の前記対向基板面には梁部を介して可動電極が形成されて、該可動電極は前記梁部によって前記固定電極側に付勢された状態で前記第２の基板から浮いた状態で該第２の基板と間隔を介して配置されており、前記可動電極と前記固定電極の少なくとも一方には相手側電極との対向面に絶縁体が設けられ、前記第２の基板には前記可動電極を前記第２の基板側に引き寄せて移動させる駆動電極が形成されており、該駆動電極に電圧を印加していないときには前記可動電極が前記絶縁体を介して前記第１と第２の固定電極に押しつけられ、前記駆動電極に電圧を印加したときには前記可動電極が前記第２の基板側に移動して前記第１と第２の固定電極から離れる方向に移動することにより前記固定電極と前記可動電極との間の容量が変化する構成と成し、前記第１の貫通孔に充填された導電体と、前記可動電極と前記第１の固定電極の間の容量部と、前記可動電極と前記第２の固定電極の間の容量部と、前記第２の貫通孔に充填された導電体とを通る経路によって信号導通経路が形成されていることをも特徴としている。 Further, according to the present invention, the insulating first substrate and the insulating second substrate are arranged with the substrate surfaces facing each other with a space therebetween, and the first substrate is arranged in the thickness direction of the substrate. A first through-hole and a second through-hole penetrating are formed, and the first and second through-holes are filled with a conductor, respectively, on the surface of the counter substrate of the first substrate. Is formed with a first fixed electrode conducting to the conductor filled in the first through hole and a second fixed electrode conducting to the conductor filled in the second through hole. A movable electrode is formed on the opposite substrate surface of the substrate through a beam portion, and the movable electrode is urged toward the fixed electrode side by the beam portion and floats from the second substrate. The second substrate is disposed at an interval, and at least one of the movable electrode and the fixed electrode An insulator is provided on the surface facing the counterpart electrode, and a driving electrode is formed on the second substrate to move the movable electrode toward the second substrate, and a voltage is applied to the driving electrode. When no voltage is applied, the movable electrode is pressed against the first and second fixed electrodes through the insulator, and when a voltage is applied to the drive electrode, the movable electrode moves to the second substrate side. Thus, the capacitance between the fixed electrode and the movable electrode is changed by moving in a direction away from the first and second fixed electrodes, and the conductor filled in the first through hole A capacitor portion between the movable electrode and the first fixed electrode, a capacitor portion between the movable electrode and the second fixed electrode, and a conductor filled in the second through hole. The signal conduction path is formed by the path It is characterized.
　本発明の可変容量素子において、絶縁性の第１の基板と絶縁性の第２の基板とが互いに間隔を介して互いに基板面を対向させて配置されている。また、可動電極は、第２の基板の対向基板面に、梁部を介して形成されている。この可動電極は、駆動電極に電圧を印加していない状態の時には、第１の基板の対向基板面に形成された固定電極側に押しつけられる。また、可動電極は、駆動電極に電圧を印加したときには、前記第２の基板側に移動して前記固定電極から離れる方向に移動するものである。 In the variable capacitance element of the present invention, the insulating first substrate and the insulating second substrate are disposed with their substrate surfaces facing each other with a gap therebetween. The movable electrode is formed on the counter substrate surface of the second substrate via a beam portion. The movable electrode is pressed against the fixed electrode formed on the counter substrate surface of the first substrate when no voltage is applied to the drive electrode. The movable electrode moves toward the second substrate and moves away from the fixed electrode when a voltage is applied to the drive electrode.
　本発明において、信号導通経路に電圧を印加すると、固定電極と可動電極との間に、互いに引き合う方向に静電力が発生するが、この静電力の方向と、前記駆動電極に電圧を印加したときの可動電極の変位方向とが逆である。そのため、本発明においては、前記信号導通経路に大電力の信号が入力されても、その影響でセルフアクチュエーションが生じることを防止できる。なお、駆動電極に電圧が印加されていて、可動電極が固定電極と離れているときには、可動電極と固定電極との間に生じる静電力は十分に小さく、可動電極の第２の基板側への移動に影響を与えない。 In the present invention, when a voltage is applied to the signal conduction path, an electrostatic force is generated in a direction attracting each other between the fixed electrode and the movable electrode. When the voltage is applied to the direction of the electrostatic force and the driving electrode, The displacement direction of the movable electrode is opposite. Therefore, in the present invention, even if a high-power signal is input to the signal conduction path, self-actuation can be prevented from occurring due to the influence. When a voltage is applied to the drive electrode and the movable electrode is separated from the fixed electrode, the electrostatic force generated between the movable electrode and the fixed electrode is sufficiently small, and the movable electrode is moved toward the second substrate side. Does not affect movement.
　また、本発明において、信号導通経路は、基板に形成した貫通孔に充填した導電体を有する経路である。したがって、従来のように、薄膜形成技術を用いて基板状に配線を形成する場合に比べ、配線の膜厚を大きくできる。そのため、配線のＥＳＲ（Ｅｑｕｉｖａｌｅｎｔ　Ｓｅｒｉｅｓ　Ｒｅｓｉｓｔａｎｃｅ：等価直列抵抗）を低減でき、高Ｑ化が可能である。 In the present invention, the signal conduction path is a path having a conductor filled in a through hole formed in the substrate. Therefore, the thickness of the wiring can be increased as compared with the conventional case where the wiring is formed in a substrate shape using a thin film forming technique. Therefore, ESR (Equivalent Series Resistance) of wiring can be reduced, and high Q can be achieved.
　さらに、本発明によれば、絶縁性を有する第１と第２の基板とに挟まれた領域に、固定電極、可動電極、駆動電極が設けられている。そのため、例えば、これらの電極形成時に、第１と第２の基板の対向面の外縁部に封止枠を形成することにより、固定電極、可動電極、駆動電極を、前記封止枠によって封止できる。このようにすると、パッケージ形成工程が不要となるため、可変容量素子を安価に形成できる。 Furthermore, according to the present invention, the fixed electrode, the movable electrode, and the drive electrode are provided in a region sandwiched between the first and second substrates having insulation properties. Therefore, for example, when these electrodes are formed, a fixed frame, a movable electrode, and a drive electrode are sealed by the sealing frame by forming a sealing frame on the outer edge portions of the opposing surfaces of the first and second substrates. it can. This eliminates the need for a package formation step, and thus makes it possible to form the variable capacitance element at a low cost.
本発明に係る可変容量素子の第１実施例の要部構成を示す断面説明図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory cross-sectional view showing a main configuration of a first embodiment of a variable capacitance element according to the present invention. 第１実施例の外観構成を示す斜視説明図である。It is a perspective explanatory view showing the appearance composition of the 1st example. 第１実施例の可変容量素子の可動部を示す模式的な斜視図である。It is a typical perspective view which shows the movable part of the variable capacitance element of 1st Example. 第１実施例の可変容量素子における第１の基板側の製造工程および、第１の基板側と第２の基板側との接合工程を説明するための、模式的な断面図である。It is typical sectional drawing for demonstrating the manufacturing process by the side of the 1st board | substrate in the variable capacitance element of 1st Example, and the joining process of the 1st board | substrate side and the 2nd board | substrate side. 第１実施例の可変容量素子における第２の基板側の製造工程を説明するための模式的な断面図である。It is typical sectional drawing for demonstrating the manufacturing process by the side of the 2nd board | substrate in the variable capacitance element of 1st Example. 第１実施例の可変容量素子において、梁部と応力付与部を異なる材料により形成した場合の温度特性を説明するための模式図である。In the variable capacitance element of 1st Example, it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with a different material. 第１実施例の可変容量素子において、梁部と応力付与部を異なる材料により形成した場合の温度特性を説明するための模式図である。In the variable capacitance element of 1st Example, it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with a different material. 第１実施例の可変容量素子において、梁部と応力付与部を同じ材料により形成した場合の温度特性を説明するための模式図である。In the variable capacitance element of 1st Example, it is a schematic diagram for demonstrating the temperature characteristic at the time of forming a beam part and a stress provision part with the same material. 本発明に係る可変容量素子の第２実施例の要部構成を示す断面説明図である。FIG. 6 is an explanatory cross-sectional view showing the main configuration of a second embodiment of the variable capacitance element according to the present invention. 第２実施例の外部電極を説明するための図である。It is a figure for demonstrating the external electrode of 2nd Example. 従来の可変容量素子の例において、スイッチオフの状態を示す断面説明図である。In the example of the conventional variable capacitance element, it is a section explanatory view showing the state of switch off. 図９ａの可変容量素子のスイッチオンの状態を示す断面説明図である。FIG. 9B is a cross-sectional explanatory diagram illustrating a switch-on state of the variable capacitance element of FIG.
符号の説明Explanation of symbols
　１　　第１の基板
　２　　第２の基板
　３　　第１の貫通孔
　４　　第２の貫通孔
　５　　固定電極
　６　　梁部
　７　　可動電極
　９　　駆動電極
　１０　ストッパ
　１３，１４　銅
　１５，１６　封止枠
　１７，１８　金膜
　２１，２２，２３　外部電極 DESCRIPTION OF SYMBOLS 1 1st board | substrate 2 2nd board | substrate 3 1st through-hole 4 2nd through-hole 5 Fixed electrode 6 Beam part 7 Movable electrode 9 Drive electrode 10 Stopper 13,14 Copper 15,16 Sealing frame 17,18 Gold Membrane 21, 22, 23 External electrode
　以下に、本発明に係る実施例を図面に基づき説明する。 Embodiments according to the present invention will be described below with reference to the drawings.
　図１には、本発明に係る可変容量素子の第１実施例が、図２のＡ－Ａ断面図により示されている。なお、図１は、模式的な断面図であり、図２に示す外部電極２１，２２，２３を省略して示している。 FIG. 1 shows a first embodiment of a variable capacitance element according to the present invention by a cross-sectional view taken along line AA of FIG. FIG. 1 is a schematic cross-sectional view, omitting the external electrodes 21, 22, and 23 shown in FIG.
　図１に示すように、絶縁性の第１の基板１と絶縁性の第２の基板２とが互いに間隔を介し、互いに基板面１１，１２を対向させて配置されている。第１と第２の基板１，２は、いずれもガラス基板である。第１と第２の基板１，２の厚みは、それぞれ、例えば３００μｍに形成されている。第１の基板１には、基板の厚み方向に貫通する第１の貫通孔（ヴィアホール（ＶＨ））３が１つ形成されている。この第１の貫通孔３の形成位置は、外部電極２１側に設けられた信号出力部３３（図２、参照）に対応する位置と成している。第２の基板２には、基板の厚み方向に貫通する第２の貫通孔（ヴィアホール）４が４つ形成されている。なお、図１には、これら第２の貫通孔４のうち、２つのみが示されているが、紙面の奥側に、同様に、２つの第２の貫通孔４が形成されている。これらの第２の貫通孔４は、信号導入部３４（図２、参照）に対応する位置に形成されている。第１と第２の貫通孔３，４には、それぞれ、導電体である銅（Ｃｕ）１３，１４が充填されている。 As shown in FIG. 1, an insulating first substrate 1 and an insulating second substrate 2 are arranged with their substrate surfaces 11 and 12 facing each other with a gap therebetween. The first and second substrates 1 and 2 are both glass substrates. Each of the first and second substrates 1 and 2 has a thickness of, for example, 300 μm. The first substrate 1 has one first through hole (via hole (VH)) 3 penetrating in the thickness direction of the substrate. The first through hole 3 is formed at a position corresponding to the signal output portion 33 (see FIG. 2) provided on the external electrode 21 side. The second substrate 2 has four second through holes (via holes) 4 penetrating in the thickness direction of the substrate. In FIG. 1, only two of the second through holes 4 are shown, but two second through holes 4 are similarly formed on the back side of the drawing. These second through holes 4 are formed at positions corresponding to the signal introduction part 34 (see FIG. 2). The first and second through holes 3 and 4 are filled with copper (Cu) 13 and 14 as conductors, respectively.
　第１の基板１の対向基板面１１には、前記第１の貫通孔３に充填された銅１３と導通する銅製の固定電極５が形成されている。この固定電極５は厚さ５μｍに形成されている。固定電極５の表面側（この図では下面側）には、絶縁体としてのストッパ１０が設けられている。このストッパ１０は、固定電極５の表面側に設けられた酸化シリコン（ＳｉＯ２）膜により形成されている。第１の基板１の対向基板面１１には、その外周側に、固定電極５とほぼ同じ高さ（厚み）の封止枠１５が形成されている。封止枠１５の先端側には、封止用の金膜１７が、約０．５μｍの厚みで形成されている。 On the counter substrate surface 11 of the first substrate 1, a copper fixed electrode 5 that is electrically connected to the copper 13 filled in the first through hole 3 is formed. The fixed electrode 5 is formed to a thickness of 5 μm. A stopper 10 as an insulator is provided on the front surface side (the lower surface side in this figure) of the fixed electrode 5. The stopper 10 is formed of a silicon oxide (SiO 2 ) film provided on the surface side of the fixed electrode 5. On the counter substrate surface 11 of the first substrate 1, a sealing frame 15 having substantially the same height (thickness) as the fixed electrode 5 is formed on the outer peripheral side thereof. A gold film 17 for sealing is formed on the front end side of the sealing frame 15 with a thickness of about 0.5 μm.
　一方、前記第２の基板２の対向基板面１２には、前記第２の貫通孔４に充填された銅１４に梁部６を介して導通する可動電極７が形成されている。該可動電極７は、前記梁部６によって前記固定電極５側に付勢された状態で、前記第２の基板２から浮いた状態で該第２の基板２と間隔を介して配置されている。前記固定電極５と可動電極７と梁部６は、いずれも約１０μｍの厚みの銅により形成されている。可動電極７は、前記ストッパ１０を介して固定電極５と接触し、容量部（コンデンサ）を形成している。梁部６の表面には、該梁部６に対して第２の基板２からの浮き上がり方向の引っ張り応力を付与する、厚さ１μｍの応力付与部８が形成されている。 On the other hand, on the counter substrate surface 12 of the second substrate 2, a movable electrode 7 is formed which is electrically connected to the copper 14 filled in the second through hole 4 via the beam portion 6. The movable electrode 7 is arranged to be spaced from the second substrate 2 while being lifted from the second substrate 2 while being urged to the fixed electrode 5 side by the beam portion 6. . The fixed electrode 5, the movable electrode 7 and the beam portion 6 are all made of copper having a thickness of about 10 μm. The movable electrode 7 is in contact with the fixed electrode 5 through the stopper 10 to form a capacitor (capacitor). On the surface of the beam portion 6, a stress applying portion 8 having a thickness of 1 μm for applying a tensile stress in the lifting direction from the second substrate 2 to the beam portion 6 is formed.
　なお、図３には、可動電極７と梁部６の模式的な斜視図が示されている。図１の断面図に示されている可動電極７と梁部６は、図３のＢ－Ｂ断面を示す。可動電極７には、ダンピングホールとして機能する貫通孔２７が複数形成されている。 FIG. 3 shows a schematic perspective view of the movable electrode 7 and the beam portion 6. The movable electrode 7 and the beam portion 6 shown in the cross-sectional view of FIG. 1 show the BB cross section of FIG. A plurality of through holes 27 functioning as damping holes are formed in the movable electrode 7.
　図１に示すように、第２の基板２の対向基板面１２には、可動電極７を第２の基板２側に引き寄せて移動させる駆動電極９が、白金（Ｐｔ）により形成されている。駆動電極９の表面には酸化シリコンの絶縁膜１９が形成されている。また、第２の基板２の対向基板面１２には、その外周側に、可動電極７とほぼ同じ高さの封止枠１６が形成されている。封止枠１６の先端側には、封止用の金膜１８が約０．５μｍの厚みで形成されている。この金膜１８と前記金膜１７とが接合している。金膜１７，１８および封止枠１５，１６の外周側には、駆動電極９の駆動用の外部電極２３（図２、参照）が形成されている。なお、図１に示す、符号２９は、クロム膜から成る密着層である。この密着層は、ガラスから成る第２の基板２と銅から成る封止枠１６とを密着させるためのものである。 As shown in FIG. 1, on the counter substrate surface 12 of the second substrate 2, a drive electrode 9 that moves the movable electrode 7 toward the second substrate 2 is formed of platinum (Pt). An insulating film 19 made of silicon oxide is formed on the surface of the drive electrode 9. Further, a sealing frame 16 having substantially the same height as the movable electrode 7 is formed on the outer peripheral side of the counter substrate surface 12 of the second substrate 2. On the front end side of the sealing frame 16, a gold film 18 for sealing is formed with a thickness of about 0.5 μm. The gold film 18 and the gold film 17 are joined. External electrodes 23 for driving the drive electrodes 9 (see FIG. 2) are formed on the outer peripheral sides of the gold films 17 and 18 and the sealing frames 15 and 16. In addition, the code | symbol 29 shown in FIG. 1 is the contact | adherence layer which consists of chromium films. This adhesion layer is for closely adhering the second substrate 2 made of glass and the sealing frame 16 made of copper.
　本実施例において、前記第２の貫通孔４に充填された銅１４と、前記梁部６と、前記第１の貫通孔３に充填された銅１３とを通る経路によって、可動電極７と固定電極５の間の容量部を介しての信号導通経路が形成されている。図２に示したように、第２の基板２の前記対向基板面１２と反対側の面には、ＲＦ（Ｒａｄｉｏ　Ｆｒｅｑｕｅｎｃｙ）の信号入力用の外部電極２２が形成されている。一方、第１の基板１の前記対向基板面１１と反対側の面には、ＲＦの信号出力用の外部電極２１が形成されている。外部電極２１の信号導出部３３が第１の貫通孔１３内の銅１３に接続され、外部電極２２の信号導入部３４が第２の貫通孔１４内の銅１４に接続されている。 In this embodiment, the movable electrode 7 and the movable electrode 7 are fixed by a path passing through the copper 14 filled in the second through hole 4, the beam portion 6, and the copper 13 filled in the first through hole 3. A signal conduction path is formed through the capacitor between the electrodes 5. As shown in FIG. 2, an RF (Radio Frequency) signal input external electrode 22 is formed on the surface of the second substrate 2 opposite to the counter substrate surface 12. On the other hand, an external electrode 21 for RF signal output is formed on the surface of the first substrate 1 opposite to the counter substrate surface 11. A signal lead-out portion 33 of the external electrode 21 is connected to the copper 13 in the first through hole 13, and a signal introduction portion 34 of the external electrode 22 is connected to the copper 14 in the second through hole 14.
　本実施例において、前記駆動電極９に電圧を印加していないときには、図１に示すように、前記可動電極７が前記ストッパ１０を介して前記固定電極５に押しつけられている。この状態においては、固定電極５と可動電極７との間隔が狭く、この間隔は、ストッパ１０の膜厚と同等である。そのため、固定電極５と可動電極との容量は、大と成している。そして、駆動電極９に電圧を印加したときには、可動電極７が第２の基板２側に移動して前記固定電極５から離れる方向に移動する。このことにより、固定電極５と可動電極７との間隔が、金膜１７，１８の厚み程に広くなり、固定電極５と可動電極７との間の容量が小さくなる方向に変化する。 In this embodiment, when no voltage is applied to the drive electrode 9, the movable electrode 7 is pressed against the fixed electrode 5 via the stopper 10, as shown in FIG. In this state, the distance between the fixed electrode 5 and the movable electrode 7 is narrow, and this distance is equal to the film thickness of the stopper 10. Therefore, the capacity of the fixed electrode 5 and the movable electrode is large. When a voltage is applied to the drive electrode 9, the movable electrode 7 moves toward the second substrate 2 and moves away from the fixed electrode 5. As a result, the distance between the fixed electrode 5 and the movable electrode 7 increases as the thickness of the gold films 17 and 18 changes, and the capacitance between the fixed electrode 5 and the movable electrode 7 decreases.
　このように、本実施例では、駆動電極９の電圧をオンオフすることにより、固定電極５と可動電極７との間の容量が変化する。 Thus, in this embodiment, the capacitance between the fixed electrode 5 and the movable electrode 7 changes by turning on and off the voltage of the drive electrode 9.
　なお、本実施例は、図４、図５に示すような工程により、図の矢印にしたがって形成される。図４の最上段に示すように、第１の基板１側では、第１の貫通孔３を形成して該第１の貫通孔３に銅１３を充填する。次に、図４の２段目に示すように、第１の基板１の対向基板面１１に、銅の選択メッキによって固定電極５と封止枠１５を形成し、ＣＭＰ（Ｃｈｅｍｉｃａｌ　Ｍｅｃｈａｎｉｃａｌ　Ｐｏｌｉｓｈｉｎｇ）によって表面研磨を行う。なお、符号３０は、選択メッキ用レジストを示している。その後、図４の３段目に示すように、固定電極５の表面（この図では下面）側に、ストッパ１０を形成し、封止枠１５の先端側（この図では、下側）に金膜１７を形成する。また、選択メッキ用レジスト３０を除去する。 In addition, a present Example is formed according to the arrow of a figure by the process as shown in FIG. 4, FIG. As shown in the uppermost stage of FIG. 4, on the first substrate 1 side, a first through hole 3 is formed, and the first through hole 3 is filled with copper 13. Next, as shown in the second stage of FIG. 4, the fixed electrode 5 and the sealing frame 15 are formed on the opposing substrate surface 11 of the first substrate 1 by selective plating of copper, and by CMP (Chemical Mechanical Polishing). Surface polishing is performed. Reference numeral 30 denotes a resist for selective plating. After that, as shown in the third stage of FIG. 4, the stopper 10 is formed on the surface (the lower surface in this figure) side of the fixed electrode 5, and the gold is formed on the tip side (the lower side in this figure) of the sealing frame 15. A film 17 is formed. Further, the selective plating resist 30 is removed.
　一方、図５の最上段に示すように、第２の基板２側にも、第２の貫通孔４を形成して、それぞれの第２の貫通孔４に銅１４を充填する。次に、図５の２段目に示すように、第２の基板２の対向基板面１２に、駆動電極９と、密着層２９と、駆動部ショート防止用の絶縁膜１９を形成する。次に、図５の３段目に示すように、犠牲層２４を形成し、該犠牲層２４の上側に、銅の選択メッキによって可動電極７と梁部６と封止枠１６とを形成する。なお、符号３１は、選択メッキ用レジストを示している。 On the other hand, as shown in the uppermost stage of FIG. 5, the second through holes 4 are also formed on the second substrate 2 side, and each second through hole 4 is filled with copper 14. Next, as shown in the second stage of FIG. 5, the drive electrode 9, the adhesion layer 29, and the insulating film 19 for preventing the drive unit short circuit are formed on the counter substrate surface 12 of the second substrate 2. Next, as shown in the third stage of FIG. 5, the sacrificial layer 24 is formed, and the movable electrode 7, the beam portion 6, and the sealing frame 16 are formed on the upper side of the sacrificial layer 24 by selective copper plating. . Reference numeral 31 denotes a resist for selective plating.
　そして、図５の４段目に示すように、選択メッキ用レジスト３１の除去と、封止枠１６の先端側（この図では、上側）への金膜１８の形成とを行う。また、梁部６の表面には、応力付与部８を形成する。この応力付与部８は、例えば白金（プラチナ）や金の内部応力よって梁部６を引っ張る応力を付与する膜により形成することができる。金膜１８の形成と同時に、応力付与部８を形成すると、可変容量素子の製造を効率的に行うことができる。次に、図５の最下段に示すように、犠牲層２４をエッチングにより除去し、応力付与部８によって、梁部６を持ち上げるようにして浮かせ、可動電極７を第２の基板２から浮かせた状態とする。 Then, as shown in the fourth row of FIG. 5, the selective plating resist 31 is removed and the gold film 18 is formed on the front end side (the upper side in this figure) of the sealing frame 16. Further, a stress applying portion 8 is formed on the surface of the beam portion 6. The stress applying portion 8 can be formed of, for example, a film that applies a stress that pulls the beam portion 6 due to an internal stress of platinum (platinum) or gold. When the stress applying portion 8 is formed simultaneously with the formation of the gold film 18, the variable capacitance element can be manufactured efficiently. Next, as shown in the lowermost stage of FIG. 5, the sacrificial layer 24 is removed by etching, and the beam application part 6 is lifted and lifted by the stress applying part 8, and the movable electrode 7 is lifted from the second substrate 2. State.
　そして、図４の最下段に示すように、前記第１の基板１と第２の基板２とを対向させ、金膜１７と金膜１８とを接合する。このことにより、第１の基板１と第２の基板２とに挟まれた空間に、固定電極５、可動電極７、梁部６、駆動電極９を封止し、かつ、可動電極７を梁部６によって固定電極５側に押しつける態様とする。その後、外部電極２１，２２，２３を形成し、ダイシングによりカットして、可変容量素子を形成する。 Then, as shown at the bottom of FIG. 4, the first substrate 1 and the second substrate 2 are opposed to each other, and the gold film 17 and the gold film 18 are bonded. As a result, the fixed electrode 5, the movable electrode 7, the beam portion 6, and the drive electrode 9 are sealed in the space between the first substrate 1 and the second substrate 2, and the movable electrode 7 is The portion 6 is pressed against the fixed electrode 5 side. Thereafter, external electrodes 21, 22, and 23 are formed and cut by dicing to form variable capacitance elements.
　本実施例は、以上のようにして製造されるものであり、第１と第２の基板１，２の貫通孔３，４に充填した銅１３，１４を有して信号導通経路を形成することにより、これらの厚みを大きくできる。このため、本実施例は、配線ロスを低減でき、高Ｑ化が可能であり、また、前記の如く、駆動電極９への電圧印加による可動電極７の変位方向と、高周波信号の信号導通経路に電圧を印加したときに発生する静電力の方向とが逆であるので、セルフアクチュエーションが生じることを防止できる。 The present embodiment is manufactured as described above, and has signal conduction paths having copper 13 and 14 filled in the through holes 3 and 4 of the first and second substrates 1 and 2. Therefore, these thicknesses can be increased. For this reason, the present embodiment can reduce the wiring loss and increase the Q. Further, as described above, the displacement direction of the movable electrode 7 by the voltage application to the drive electrode 9 and the signal conduction path of the high-frequency signal. Since the direction of the electrostatic force generated when a voltage is applied to is reversed, self-actuation can be prevented.
　また、本実施例によれば、固定電極５の形成時および駆動電極７と梁部６の形成時に、封止枠１５，１６を形成できる。そして、この封止枠１５，１６と第１および第２の基板１，２とにより挟まれた空間内に、固定電極５、可動電極７、駆動電極９を封止できるので、パッケージ形成工程が不要であり、パッケージ形成部でロスを防止し、可変容量素子を安価に形成できる。 Further, according to the present embodiment, the sealing frames 15 and 16 can be formed when the fixed electrode 5 is formed and when the drive electrode 7 and the beam portion 6 are formed. And since the fixed electrode 5, the movable electrode 7, and the drive electrode 9 can be sealed in the space sandwiched between the sealing frames 15 and 16 and the first and second substrates 1 and 2, the package forming step can be performed. This is unnecessary, can prevent loss at the package forming portion, and can form the variable capacitance element at low cost.
　さらに、本実施例は、可動電極７と梁部６を銅により形成しており、銅の抵抗が低抵抗であるため、ＥＳＲをより一層低減できる。 Furthermore, in this embodiment, the movable electrode 7 and the beam portion 6 are made of copper, and the resistance of copper is low, so that ESR can be further reduced.
　なお、応力付与部８の形成において、該応力付与部８を梁部６と同一材料で形成することもできる。この場合、図５の３段目に示した銅メッキによる可動電極７等の形成の後、応力付与部８としての銅膜を、梁部６の表面に高温（例えば８０℃）で成膜して形成する。 In addition, in forming the stress applying portion 8, the stress applying portion 8 can be formed of the same material as the beam portion 6. In this case, after forming the movable electrode 7 and the like by copper plating shown in the third stage of FIG. 5, a copper film as the stress applying portion 8 is formed on the surface of the beam portion 6 at a high temperature (for example, 80 ° C.). Form.
　なお、この銅膜の高温成膜時に、第２の基板２上の銅膜（梁部６や可動電極７等の形成用の銅膜）も同じ温度に高められることにより熱膨張しようとするが、第２の基板２上の銅膜は、ガラス基板である第２の基板２と一体となっているために、膨張することができない。それに対し、高温成膜される銅膜は、この成膜温度に対応して低温時よりも熱膨張した状態で成膜される。そのため、高温成膜された応力付与部用の膜は、成膜後に温度が下がったときに熱収縮し、犠牲層２４が除去されると、応力付与部８が梁部６に引っ張り応力を付与する態様となり、可動電極７を浮き上がらせる方向に応力を付与できる。なお、本発明者の実験によれば、例えば、１０μｍの梁部６に対し、１μｍの銅製の応力付与部８を設けて、可動電極７を８μｍ程度浮き上がらせることができた。 When the copper film is formed at a high temperature, the copper film on the second substrate 2 (the copper film for forming the beam portion 6, the movable electrode 7 and the like) is also raised to the same temperature, so that thermal expansion is attempted. The copper film on the second substrate 2 cannot be expanded because it is integrated with the second substrate 2 which is a glass substrate. On the other hand, the copper film formed at a high temperature is formed in a state of thermal expansion from the low temperature corresponding to the film formation temperature. Therefore, the film for the stress applying portion formed at a high temperature is thermally contracted when the temperature is lowered after the film formation, and when the sacrificial layer 24 is removed, the stress applying portion 8 applies a tensile stress to the beam portion 6. Thus, stress can be applied in the direction in which the movable electrode 7 is lifted. According to the experiment of the present inventor, for example, a 1 μm copper stress applying portion 8 is provided for a 10 μm beam portion 6 and the movable electrode 7 can be lifted by about 8 μm.
　また、このように、応力付与部８を銅により形成すると、以下の効果を奏することができる。つまり、梁部６を形成する銅と異なる材料である金や白金等によって応力付与部８を形成すると、梁部６と応力付与部８との線膨張係数の違いによって、温度変化に応じて梁部６の反りが、図６ａ、図６ｂの破線に示すように変化する。そして、梁部６の先端側に設けられる可動電極７が、図６ｂの矢印に示すように上下してしまい、梁部６によって可動電極７を固定電極５側に押しつける力が温度によって変化してしまう。 Further, when the stress applying portion 8 is formed of copper as described above, the following effects can be obtained. That is, when the stress applying portion 8 is formed of gold, platinum, or the like, which is a material different from copper forming the beam portion 6, the beam according to the temperature change due to the difference in linear expansion coefficient between the beam portion 6 and the stress applying portion 8. The warping of the portion 6 changes as shown by the broken lines in FIGS. 6a and 6b. Then, the movable electrode 7 provided on the distal end side of the beam portion 6 moves up and down as shown by the arrow in FIG. 6b, and the force pressing the movable electrode 7 toward the fixed electrode 5 side by the beam portion 6 varies depending on the temperature. End up.
　それに対し、図６ｃに示すように、梁部６を形成する銅と同一材料で応力付与部８を形成すると、梁部６と応力付与部８との線膨張係数が等しいため、温度変化に応じて梁部６が上下してしまうことがない。したがって、梁部６によって可動電極７を固定電極５側に押しつける力を温度によらず一定にできるメリットがある。言い換えれば、温度変化が発生した場合でも、梁部６により可動電極７を固定電極５側に付勢する力の変化がほとんど発生しない。そのため、固定電極５と可動電極７との容量の温度依存性を低減できる。したがって、梁部６を形成する銅と同一材料で応力付与部８を形成すると、可変容量素子によって広い温度範囲で同様の動作を行う場合の印加電圧を小さくできる。 On the other hand, as shown in FIG. 6 c, when the stress applying portion 8 is formed of the same material as the copper forming the beam portion 6, the linear expansion coefficient of the beam portion 6 and the stress applying portion 8 is equal. Therefore, the beam portion 6 does not go up and down. Therefore, there is an advantage that the force pressing the movable electrode 7 toward the fixed electrode 5 by the beam portion 6 can be made constant regardless of the temperature. In other words, even when a temperature change occurs, a change in the force that urges the movable electrode 7 toward the fixed electrode 5 by the beam portion 6 hardly occurs. Therefore, the temperature dependence of the capacitance between the fixed electrode 5 and the movable electrode 7 can be reduced. Therefore, when the stress applying portion 8 is formed of the same material as the copper forming the beam portion 6, the applied voltage when the same operation is performed in a wide temperature range by the variable capacitance element can be reduced.
　次に、本発明に係る可変容量素子の第２実施例について説明する。なお、第２実施例の説明において、第１実施例と同一名称部分には同一符号を付し、その重複説明は省略または簡略化する。 Next, a second embodiment of the variable capacitance element according to the present invention will be described. In the description of the second embodiment, parts having the same names as those in the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted or simplified.
　図７には、第２実施例の可変容量素子が模式的な断面図により示されている。同図に示すように、第２実施例では、第１の基板１に、基板の厚み方向に貫通する第１の貫通孔３と第２の貫通孔４とを形成している。これら第１と第２の貫通孔３，４にはそれぞれ銅１３，１４を充填している。 FIG. 7 is a schematic cross-sectional view showing the variable capacitance element of the second embodiment. As shown in the figure, in the second embodiment, a first through-hole 3 and a second through-hole 4 that penetrate in the thickness direction of the substrate are formed in the first substrate 1. These first and second through holes 3 and 4 are filled with copper 13 and 14, respectively.
　図８に示すように、第１の基板１の対向基板面１１と反対側の面３８には、ＲＦ信号出力用の外部電極２２とＲＦ信号入力用の外部電極２１とが、互いに間隔を介して設けられている。また、信号導入部３４と信号導出部３３とが設けられている。また、封止枠１５，１７の外周側には、前記第１実施例と同様に、駆動電極９の駆動用の外部電極２３が設けられている（図示せず）。なお、この外部電極２３を、図８の破線に示すように、第１の基板１の対向基板面１１と反対側の面に設けて、駆動電極９を図７の破線Ａに示すように、第１の基板１側から外部電極２３に導通させることもできる。 As shown in FIG. 8, the RF signal output external electrode 22 and the RF signal input external electrode 21 are spaced from each other on the surface 38 opposite to the counter substrate surface 11 of the first substrate 1. Is provided. Further, a signal introducing unit 34 and a signal deriving unit 33 are provided. Further, on the outer peripheral side of the sealing frames 15 and 17, an external electrode 23 for driving the drive electrode 9 is provided (not shown) as in the first embodiment. The external electrode 23 is provided on the surface opposite to the counter substrate surface 11 of the first substrate 1 as shown by a broken line in FIG. 8, and the drive electrode 9 is shown as a broken line A in FIG. It is also possible to conduct to the external electrode 23 from the first substrate 1 side.
　第１の貫通孔３に充填された銅１３が信号導入部３３に導通し、第２の貫通孔４に充填された銅１４が信号導出部３４に導通する。また、第１の基板１の対向基板面１１には、第１の貫通孔３に充填された銅１３に導通する第１の固定電極５（５ａ）と、前記第２の貫通孔４に充填された銅１４に導通する第２の固定電極５（５ｂ）とが形成されている。第２の基板２の対向基板面１２には、梁部６を介して可動電極７が形成されている。 The copper 13 filled in the first through-hole 3 is conducted to the signal introducing portion 33, and the copper 14 filled in the second through-hole 4 is conducted to the signal deriving portion 34. Further, the counter substrate surface 11 of the first substrate 1 is filled in the first fixed electrode 5 (5a) conducting to the copper 13 filled in the first through hole 3 and the second through hole 4. A second fixed electrode 5 (5b) that is electrically connected to the formed copper 14 is formed. A movable electrode 7 is formed on the counter substrate surface 12 of the second substrate 2 via a beam portion 6.
　第２実施例において、駆動電極９に電圧を印加していないときには、可動電極７がストッパ１０を介して第１と第２の固定電極５ａ，５ｂに押しつけられる。一方、駆動電極９に電圧を印加したときには、可動電極７が第２の基板側２に移動して、第１と第２の固定電極５ａ，５ｂから離れる方向に移動する。このような、可動電極７の動作により、固定電極５と可動電極７との間の容量が変化する。 In the second embodiment, when no voltage is applied to the drive electrode 9, the movable electrode 7 is pressed against the first and second fixed electrodes 5a and 5b via the stopper 10. On the other hand, when a voltage is applied to the drive electrode 9, the movable electrode 7 moves to the second substrate side 2 and moves away from the first and second fixed electrodes 5a and 5b. By such an operation of the movable electrode 7, the capacitance between the fixed electrode 5 and the movable electrode 7 changes.
　また、第２実施例においては、第１の貫通孔３に充填された銅１３と、可動電極７と第１の固定電極５ａの間の容量部と、可動電極７と第２の固定電極５ｂの間の容量部と、前記第２の貫通孔４に充填された銅１４とを通る経路によって、信号導通経路が形成されている。第２の実施例においては、可動電極７と第１の固定電極５ａの間の容量部（コンデンサ）と、可動電極７と第２の固定電極５ｂの間の容量部が直列に接続された構成と成している。 In the second embodiment, the copper 13 filled in the first through-hole 3, the capacitor between the movable electrode 7 and the first fixed electrode 5a, and the movable electrode 7 and the second fixed electrode 5b are used. A signal conduction path is formed by a path passing through the capacitor portion between the first through hole 4 and the copper 14 filled in the second through hole 4. In the second embodiment, the capacitor (capacitor) between the movable electrode 7 and the first fixed electrode 5a and the capacitor between the movable electrode 7 and the second fixed electrode 5b are connected in series. It is made.
　第２実施例の前記以外の構成は、前記第１実施例と同様に構成されている。また、第２実施例では、その製造に際し、第１と第２の貫通孔３，４の形成および、これらの貫通孔３，４に充填される銅１３，１４と接続させて、第１と第２の固定電極５ａ，５ｂを形成する。それ以外は、第２実施例も、前記第１実施例と同様に製造される。また、第２実施例は、前記の如く、第１実施例とほぼ同様に動作し、第１実施例と同様の効果を奏することができる。 Other configurations of the second embodiment are the same as those of the first embodiment. In the second embodiment, the first and second through holes 3 and 4 are formed and the copper 13 and 14 filled in the through holes 3 and 4 are connected to the first and second through holes. Second fixed electrodes 5a and 5b are formed. Otherwise, the second embodiment is manufactured in the same manner as the first embodiment. Further, as described above, the second embodiment operates in substantially the same manner as the first embodiment, and can achieve the same effects as the first embodiment.
　なお、本発明は前記各実施例に限定されるものではなく、様々な実施の形態を採り得る。例えば、可動電極７、梁部６等の形成パターンは、図３に示したパターンに限定されることはなく、適宜設定されるものである。 The present invention is not limited to the above-described embodiments, and various embodiments can be adopted. For example, the formation pattern of the movable electrode 7, the beam portion 6 and the like is not limited to the pattern shown in FIG. 3, and is appropriately set.
　また、可動電極７、梁部６、第１と第２の貫通孔３，４に充填する導電体を、いずれも銅により形成したが、これらは、銅とは限らない。つまり、銅以外の銀（Ａｇ）、金（Ａｕ）等の導電体を、適宜、第１と第２の貫通孔３，４に充填することができる。また、駆動電極９も適宜の導電体により形成される。 Further, although the conductors filling the movable electrode 7, the beam portion 6, and the first and second through holes 3 and 4 are all made of copper, these are not necessarily copper. That is, conductors such as silver (Ag) and gold (Au) other than copper can be appropriately filled in the first and second through holes 3 and 4. The drive electrode 9 is also formed of a suitable conductor.
　さらに、前記各実施例では、第１と第２の基板１，２は、いずれもガラス基板とした。しかし、これら第１、第２の基板１，２は、セラミック、アルミナ、シリコン、ガリウムヒ素（ＧａＡｓ）等の他の絶縁性材料を用いて成る絶縁性の基板としてもよい。さらに、導電性を有する材料の表面を絶縁性材料で被膜して成る絶縁性の基板としてもよい。 Further, in each of the above embodiments, the first and second substrates 1 and 2 are both glass substrates. However, the first and second substrates 1 and 2 may be insulating substrates made of other insulating materials such as ceramic, alumina, silicon, and gallium arsenide (GaAs). Furthermore, an insulating substrate formed by coating the surface of a conductive material with an insulating material may be used.
　さらに、前記各実施例では、絶縁体であるストッパ１０を固定電極５の表面側に設けた。しかし、絶縁体は、可動電極７の表面側（固定電極との対向面）に設けてもよいし、固定電極５と可動電極７の両方において、相手側電極との対向面に設けてもよい。 Further, in each of the above embodiments, the stopper 10 which is an insulator is provided on the surface side of the fixed electrode 5. However, the insulator may be provided on the surface side of the movable electrode 7 (surface facing the fixed electrode), or may be provided on the surface facing the counterpart electrode in both the fixed electrode 5 and the movable electrode 7. .
　本発明において特有な構成を備えることによって、高Ｑ化が可能であり、信号入力時にセルフアクチュエーションが発生せず、安価な可変容量素子を形成できるので、スイッチ等として様々な電気回路に適用することが可能である。 By providing a configuration unique to the present invention, high Q is possible, self-actuation does not occur at the time of signal input, and an inexpensive variable capacitance element can be formed, so that it can be applied to various electric circuits as a switch or the like. It is possible.

Claims (4)

  1. 　絶縁性の第１の基板と絶縁性の第２の基板とが互いに間隔を介して互いに基板面を対向させて配置され、前記第１の基板には基板の厚み方向に貫通する第１の貫通孔が、前記第２の基板には基板の厚み方向に貫通する第２の貫通孔がそれぞれ形成されて、これら第１と第２の貫通孔にはそれぞれ導電体が充填されており、前記第１の基板の前記対向基板面には前記第１の貫通孔に充填された導電体と導通する固定電極が形成され、前記第２の基板の前記対向基板面には前記第２の貫通孔に充填された導電体に梁部を介して導通する可動電極が形成されて、該可動電極は前記梁部によって前記固定電極側に付勢された状態で前記第２の基板から浮いた状態で該第２の基板と間隔を介して配置されており、前記可動電極と前記固定電極の少なくとも一方には相手側電極との対向面に絶縁体が設けられ、前記第２の基板には前記可動電極を前記第２の基板側に引き寄せて移動させる駆動電極が形成されており、該駆動電極に電圧を印加していないときには前記可動電極が前記絶縁体を介して前記固定電極に押しつけられ、前記駆動電極に電圧を印加したときには前記可動電極が前記第２の基板側に移動して前記固定電極から離れる方向に移動することにより前記固定電極と前記可動電極との間の容量が変化する構成と成し、前記第２の貫通孔に充填された導電体と前記梁部と前記第１の貫通孔に充填された導電体を通る経路によって前記可動電極と前記固定電極の間の容量部を介しての信号導通経路が形成されていることを特徴とする可変容量素子。 An insulating first substrate and an insulating second substrate are disposed with their substrate surfaces facing each other with a space therebetween, and the first substrate penetrates in the thickness direction of the substrate. The second substrate is formed with second through holes penetrating in the thickness direction of the substrate, and the first and second through holes are filled with a conductor, respectively. A fixed electrode is formed on the surface of the counter substrate of the first substrate and is electrically connected to the conductor filled in the first through hole. The surface of the counter substrate of the second substrate is formed on the second through hole. A movable electrode that conducts through the beam portion is formed on the filled conductor, and the movable electrode is urged toward the fixed electrode by the beam portion and floats from the second substrate. It is arranged with a distance from the second substrate, and there are few movable electrodes and fixed electrodes. The other is provided with an insulator on the surface facing the counterpart electrode, and the second substrate is provided with a drive electrode that draws and moves the movable electrode toward the second substrate. When no voltage is applied to the electrode, the movable electrode is pressed against the fixed electrode through the insulator, and when a voltage is applied to the drive electrode, the movable electrode moves to the second substrate side and The capacitance between the fixed electrode and the movable electrode is changed by moving in a direction away from the fixed electrode, and the conductor filled in the second through hole, the beam portion, and the first A variable-capacitance element characterized in that a signal conduction path through a capacitor portion between the movable electrode and the fixed electrode is formed by a path passing through a conductor filled in the through hole.
  2. 　絶縁性の第１の基板と絶縁性の第２の基板とが互いに間隔を介して互いに基板面を対向させて配置され、前記第１の基板には基板の厚み方向に貫通する第１の貫通孔と第２の貫通孔とが形成されて、これら第１と第２の貫通孔にはそれぞれ導電体が充填されており、前記第１の基板の前記対向基板面には前記第１の貫通孔に充填された導電体に導通する第１の固定電極と前記第２の貫通孔に充填された導電体に導通する第２の固定電極とが形成され、前記第２の基板の前記対向基板面には梁部を介して可動電極が形成されて、該可動電極は前記梁部によって前記固定電極側に付勢された状態で前記第２の基板から浮いた状態で該第２の基板と間隔を介して配置されており、前記可動電極と前記固定電極の少なくとも一方には相手側電極との対向面に絶縁体が設けられ、前記第２の基板には前記可動電極を前記第２の基板側に引き寄せて移動させる駆動電極が形成されており、該駆動電極に電圧を印加していないときには前記可動電極が前記絶縁体を介して前記第１と第２の固定電極に押しつけられ、前記駆動電極に電圧を印加したときには前記可動電極が前記第２の基板側に移動して前記第１と第２の固定電極から離れる方向に移動することにより前記固定電極と前記可動電極との間の容量が変化する構成と成し、前記第１の貫通孔に充填された導電体と、前記可動電極と前記第１の固定電極の間の容量部と、前記可動電極と前記第２の固定電極の間の容量部と、前記第２の貫通孔に充填された導電体とを通る経路によって信号導通経路が形成されていることを特徴とする可変容量素子。 An insulating first substrate and an insulating second substrate are disposed with their substrate surfaces facing each other with a space therebetween, and the first substrate penetrates in the thickness direction of the substrate. A hole and a second through hole are formed, and each of the first and second through holes is filled with a conductor, and the first through hole is formed on the counter substrate surface of the first substrate. The counter substrate of the second substrate is formed with a first fixed electrode conducting to the conductor filled in the hole and a second fixed electrode conducting to the conductor filled in the second through-hole. A movable electrode is formed on the surface via a beam portion, and the movable electrode is lifted from the second substrate in a state of being biased toward the fixed electrode side by the beam portion and the second substrate. Arranged at an interval, and at least one of the movable electrode and the fixed electrode has a counterpart electrode An insulator is provided on the opposite surface, and a driving electrode is formed on the second substrate to draw and move the movable electrode toward the second substrate. When no voltage is applied to the driving electrode The movable electrode is pressed against the first and second fixed electrodes through the insulator, and when a voltage is applied to the drive electrode, the movable electrode moves to the second substrate side and the first and second The capacitance between the fixed electrode and the movable electrode is changed by moving in a direction away from the second fixed electrode, and the conductor filled in the first through hole, and the movable electrode And the first fixed electrode, the capacitive part between the movable electrode and the second fixed electrode, and a path through the conductor filled in the second through hole. Variable volume characterized by the formation of a path Element.
  3. 　可動電極と梁部は銅により形成されていることを特徴とする請求項１または請求項２記載の可変容量素子。 3. The variable capacitance element according to claim 1, wherein the movable electrode and the beam portion are made of copper.
  4. 　梁部の表面には、該梁部に対して第２の基板からの浮き上がり方向の引っ張り応力を付与する応力付与部が形成されており、該応力付与部は前記梁部と同一材料で形成されていることを特徴とする請求項１または請求項２記載の可変容量素子。 On the surface of the beam portion, there is formed a stress applying portion for applying a tensile stress in the lifting direction from the second substrate to the beam portion, and the stress applying portion is formed of the same material as the beam portion. The variable capacitance element according to claim 1, wherein the variable capacitance element is provided.
PCT/JP2009/051972 2008-03-11 2009-02-05 Variable capacitance element WO2009113344A1 (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005027257A1 (en) * 2003-09-08 2005-03-24 Murata Manufacturing Co., Ltd. Variable capacitance element
JP2007324336A (en) * 2006-05-31 2007-12-13 Toshiba Corp Variable capacity device and cellular phone

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005027257A1 (en) * 2003-09-08 2005-03-24 Murata Manufacturing Co., Ltd. Variable capacitance element
JP2007324336A (en) * 2006-05-31 2007-12-13 Toshiba Corp Variable capacity device and cellular phone

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