JP5325893B2 - Variable capacitance element, manufacturing method thereof, and capacitance setting method thereof - Google Patents

Description

  The present invention relates to a variable capacitance element (capacitor) that changes its capacitance by changing a distance between electrodes, a method for manufacturing the variable capacitance element, and a control method for the variable capacitance element.

  In general, a variable capacitance element (capacitor) or a varactor whose capacitance is variable is an essential component for a high frequency circuit such as a variable frequency transmitter, a tuning amplifier, a phase shifter, and an impedance matching circuit. In particular, in recent years, development of multi-band and multi-mode mobile communication terminal devices has progressed, and accordingly, a variable capacitance element (capacitor) for realizing variable capacitance operation in a wide band is expected. Yes.

  Conventionally, as such a variable capacitance element (capacitor), for example, a varactor diode which is a semiconductor element has been used, as is also known from the following Patent Documents 1 and 2, and further, in order to realize a wider bandwidth. In addition, a structure combining a switch and a capacitor array has been proposed.

  In addition, according to the following Patent Documents 3 to 5, the electrostatic drive type variable capacitance element created by the MEMS technology is already known, and according to such a capacitance element, the loss is small compared to the semiconductor element, It is reported that there is a merit that can increase the Q value.

  Furthermore, according to the following Patent Document 6, a variable capacitance element using a movable electrode formed by laminating three metal thin films is disclosed, and according to Patent Document 7, a variable gap device using a rubber plate and The manufacturing method is already known.

  On the other hand, as an actuator for driving the movable electrode, generally, a piezoelectric actuator, an electromagnetic actuator, a polymer actuator, etc. are already known in addition to an electrostatic actuator. In addition, although different from the variable capacitance element to which the present invention relates, in particular, an actuator using a polymer material is already known from Patent Document 8 below, and such an actuator can be manufactured by a printing process. Therefore, a small and lightweight actuator can be manufactured at low cost, and practical application is expected.

JP 2004-48589 A JP 2006-157767 A JP 2004-172504 A JP 2006-19724 A JP 2006-210843 A Republished WO2005 / 027257 Japanese Patent Laid-Open No. 62-501387 JP 2006-325335 A

  However, according to the above-described prior art, there are the following problems. That is, when the variable capacitance element is formed of a semiconductor element, the number of elements increases, and when the variable capacitance element is formed on the same chip, the occupied area increases. I can't. Moreover, the variable capacitance element obtained by this has a loss larger than the variable capacitance element by MEMS technology, and Q value is low.

  In addition, it is difficult to manufacture a variable capacitor using the electrostatic drive type MEMS technology at a low cost because it is necessary to increase the chip size or the number of elements in order to increase the capacitance adjustment range. . In addition, a so-called “pull-down phenomenon” occurs in which the electrodes are too close to each other and are attracted abruptly. In order to avoid such a phenomenon, a high voltage must be controlled. It is necessary to store in a hermetically sealed package in order to prevent foreign matter and sticking between them. Therefore, it is difficult to manufacture the entire system at low cost.

  Accordingly, an object of the present invention is to provide a novel variable capacitance element that can be manufactured at low cost by employing an organic actuator. The organic actuator can be expected to be manufactured at a low cost even when the element size is increased. However, since it operates by thermal expansion accompanying Joule heat, a current is supplied to maintain an arbitrary displacement. Although the control voltage can be lowered as compared with other voltage control type actuators, the power consumption is increased.

  Therefore, in the present invention, the problem in adopting such an organic actuator is solved, that is, a low-power consumption operation is possible and a highly reliable capacitance variable element and a method for manufacturing the same are provided. It is an object of the present invention to provide a capacitance setting method for such a capacitance variable element.

In the present invention, in order to achieve the above-described object, first, two opposing substrates, electrodes formed on opposing surfaces of the two opposing substrates, and one of the two opposing electrodes And a dielectric layer provided on the surface of the capacitor, and forming a capacitance with the two opposing electrodes and the dielectric layer disposed between the two electrodes. between the two board, at least, provided with forming two organic actuators obtained by forming an organic actuator material in layers, a driving electrode for supplying driving power to the organic actuator respectively, wherein Supply drive power to two organic actuators and extend them to supply drive power to one organic actuator while supplying drive power to the other organic actuator There is provided a variable capacitance element configured such that, when stopped, contraction of the other organic actuator is constrained by the one organic actuator, and the other organic actuator is stabilized in a constrained extended state .

Further, in the present invention, in the variable capacitance element as described in the above, organic actuator before Symbol hand, the is formed on a surface of the other electrode of the two electrodes, organic actuator before Symbol other hand, the between the two board to the opposite, it is preferable that is provided adjacent to the one organic actuator, furthermore, the other organic actuator, it said formed to surround one organic actuators Preferably it is.

  Further, according to the present invention, in order to achieve the above-described object, two opposing substrates are prepared, and electrode layers are respectively formed on the opposing surfaces of the two substrates, and one of the two substrates is formed. On the opposing surface of the substrate, two organic actuators formed by layering organic actuator materials are formed, and on the opposing surface of the other substrate of the two substrates, on the surface of the formed electrode. A dielectric layer is formed, and the two substrates are bonded together so that the dielectric layer formed on the opposite surface of the other substrate faces the electrode layer formed on the opposite surface of the one substrate. Thus, there is provided a method of manufacturing a variable capacitance element that manufactures a variable capacitance element having a variable capacitance formed by the two opposing electrode layers and the dielectric layer disposed therebetween. In the above manufacturing method, one of the two organic actuators is preferably formed by a film forming method.

In addition, in order to achieve the above-mentioned object, according to the present invention, two opposing substrates, electrodes formed on opposing surfaces of the two opposing substrates, and the two opposing electrodes A dielectric layer provided on the surface of one of the electrodes, and forming a capacitance with the two opposing electrodes and the dielectric layer disposed therebetween, further comprising: , between the two board to the opposite, at least, to form a two organic actuators obtained by forming an organic actuator material in layers, a driving electrode for supplying driving power to the organic actuator A method of setting the capacitance of each of the variable capacitance elements provided, wherein both of the two organic actuators are driven and displaced, and one organic actuator of the two organic actuators is displaced. Provided is a capacitance setting method for a variable capacitance element in which the capacitance is variably set by setting the position of the other organic actuator in a steady state and then setting the position of the one organic actuator. Is done.

  In the present invention, in the capacitance setting method described above, when setting the position of the other organic actuator, the driving power necessary to maintain a steady state is supplied to the one organic actuator. At the same time, it is preferable to stop the driving power to the other organic actuator, and furthermore, when setting the position of the one organic actuator, the supply of the driving power to the one organic actuator is stopped. It is preferable to return to the initial state.

  As described above, according to the present invention, it is possible to provide a variable capacitance element having a highly reliable structure capable of low power consumption operation while adopting an organic actuator, and its According to the manufacturing method, it can manufacture easily by a printing process. In addition, according to the above-described capacitance setting method for the variable capacitance element, it is possible to drive the organic actuator in the variable capacitance element to set the capacitance variably.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  First, FIGS. 1 to 4 of the accompanying drawings show the structure of a cantilever type variable capacitance element according to the first embodiment (Example 1) of the present invention. It is a perspective view which shows the whole structure of the variable capacitance element of invention, FIG. 2 is the side view. Further, FIG. 3 attached hereto is a perspective view of the variable capacitance element shown with a part cut away for easy understanding of the internal structure, and FIG. 4 is a top view of the variable capacitance element viewed from above. FIG.

  As is apparent from these drawings, the variable capacitance element according to the present invention includes a first substrate (main substrate) 1 and has an upper surface at a predetermined position in the longitudinal direction (horizontal direction in the drawing). A plurality of electrode layers are formed. More specifically, in this example, as clearly shown in the attached FIGS. 3 and 4, five electrodes are formed from the left side of the figure, the electrode layer 2, the electrode layer 3 and the electrode layer 4, and Electrode layer 5 and electrode layer 6 are formed. Furthermore, the following members are respectively formed on the upper surfaces of these electrode layers 2, 3, 4, 5 and 6. That is, the conductive adhesive layer 13 made of a conductive adhesive is formed on the upper surface of the electrode 2, and the upper surfaces of the electrode layers 3 and 4 are made of an organic material that will be described below across the two electrode layers. The first actuator layer 11 is formed on the upper surfaces of the electrode layers 5 and 6, and the second actuator layer 12 made of an organic material, which will also be described below, is formed across these two electrodes. .

  A dielectric layer 15 is formed on the upper surface of the first actuator layer 11, and an electrode layer 7 is formed across the upper surface of the dielectric layer 15 and the upper surface of the conductive adhesive layer 13. Furthermore, a second substrate (sub-substrate) 14 is attached across the upper surface of the electrode layer 7 and the upper surface of the second actuator layer 12.

  That is, the variable capacitance element configured as described above is electrostatically formed by the dielectric layer 15 formed between the first actuator layer 11 and the electrode 7 which are formed on the upper surface of the electrode layer 3 to form a conductive layer. A capacitance is formed and the capacitance is varied by the first actuator layer 11 and the second actuator layer 12.

  Subsequently, the manufacturing method of the variable capacitance element of the present invention will be described in detail with reference to FIGS. 5 to 10 show the manufacturing process on the fixed electrode side in which various fixed electrodes are formed on the first substrate (main substrate) 1 of the variable capacitance element, and FIGS. These show manufacturing steps on the movable electrode side in which the movable electrode is formed on the first substrate (sub-substrate) 14 of the variable capacitance element.

  First, the attached perspective view shown in FIG. 5 shows the state of the first substrate 1 immediately after the electrodes are formed. As shown in this figure, for example, a glass epoxy substrate, a polyimide substrate, etc. Electrode layers 2, 3, 4, and 5 are formed on the upper surface of a first substrate 1 formed by forming a so-called insulating material in a plate shape, such as an organic substrate, an inorganic substrate such as a glass substrate, or a ceramic substrate. For the formation of these electrodes, for example, as in the case of a wiring board such as a printed circuit board, an insulating substrate with a metal foil (for example, copper foil) pasted on its surface is prepared and etching is performed, mask vapor deposition, or selective plating It is possible to adopt a method such as That is, a general electrode forming method can be used, and in addition to the above, for example, a forming method by direct application drawing with an ink or paste using metal nanoparticles can be employed. Also, FIG. 6 attached is a top view immediately after forming the electrode layers 2, 3, 4 and 5, and as described above, the electrode layer 2, the electrode layer 3 and the electrode layer 4 from the left side of the figure. Then, the electrode layer 5 and the electrode layer 6 are formed.

  Next, FIG. 7 attached shows a state after the first actuator 11 is formed. As shown in this figure, the electrodes 3 and 4 are connected to each other, that is, these The actuator 11 is formed across the electrodes. As a material for this actuator, for example, the same applicant as the present application filed on May 19, 2005 and published on November 30, 2006. As disclosed in Japanese Patent Laid-Open No. 2006-325335, a polymer material having a large absolute value of thermal expansion coefficient mixed with conductive fine particles (simply referred to as “organic actuator material”) is used. That is, it is obtained by applying a paste made of a conductive filler and an epoxy resin by a dispenser, screen printing or the like and then curing it by heating or a chemical reaction. FIG. 8 attached herewith is a top view of the first substrate 1 after the first actuator 11 is formed.

  The attached FIG. 9 shows a state after the second actuator 12 and the conductive adhesive layer 13 are formed in addition to the first actuator 11 described above. The second actuator 12 is also formed across the electrodes 5 and 6 in the same manner as the first actuator 11, and a paste made of a conductive filler and an epoxy resin is applied by a dispenser or screen printing. And then cured by heating or chemical reaction. The conductive adhesive layer 13 is coated with a conductive adhesive on the upper surface of the electrode 2. In addition, attached FIG. 10 is a top view of the 1st board | substrate 1 at this time.

  On the other hand, separately from the first substrate 1 described above, a second substrate 14 is prepared, and an electrode 7 is formed on one surface (the upper surface in the drawing). The second substrate 14 is also a so-called insulating material such as a glass epoxy substrate, an organic substrate such as a polyimide substrate, an inorganic substrate such as a glass substrate, or a ceramic substrate, like the first substrate 1. Is formed in a plate shape. Similarly to the electrode layers 2, 3, 4, and 5, the electrode 7 is etched by preparing an insulating substrate having a metal foil (for example, copper foil) pasted on one surface of the second substrate 14. A method by processing, a method by mask vapor deposition, selective plating, or the like can be employed. Furthermore, in addition to the above, for example, a formation method by direct coating and drawing with an ink or paste using metal nanoparticles may be employed. That is, the attached FIG. 11 shows the second substrate 14 immediately after forming the electrode 7 on the upper surface, and the attached FIG. 12 is a top view thereof.

  Subsequently, as shown in FIG. 13 attached, a dielectric film 15 is formed on the formed electrode 7 as an electrode protective film. The material forming the dielectric film 15 is preferably a ferroelectric. More specifically, the ferroelectric material may be a barium titanate (BTO) composite material for coating. Also, FIG. 14 attached is a top view of the second substrate 14 after the dielectric layer 15 is formed.

  Thereafter, as shown in FIG. 15 attached, the second substrate 14 on which the electrode 7 and the dielectric layer 15 are formed is turned over so that the formed dielectric layer 15 faces downward (see the arrow in the figure). ), And so as to face the upper surface of the first substrate 1 shown in FIG. 9 and FIG. That is, bonding is performed so that the electrode 7 faces the conductive adhesive layer 13, the dielectric layer 15 faces the first actuator 11, and the lower surface of the second substrate 14 faces the second actuator 12. After this bonding, the conductive adhesive layer 13 and the actuator 12 are cured. As a result, a capacitance is formed between the first actuator 11 and the electrode 7 protected (covered) by the dielectric layer 15, that is, constitutes a capacitance. As described above, a variable capacitance element can be obtained by changing the capacitance formed by the action of the first actuator layer 11 and the second actuator layer 12. The capacitance at this time is measured between the terminals of the electrode 2 and the electrode 3 because the electrode 7 and the electrode 2 are electrically connected through the conductive adhesive layer 13. Can (get).

  Next, regarding the variable capacitance element of the present invention whose detailed structure and the manufacturing method have been described above, the operation (principle) and the capacitance setting method will be described with reference to FIGS. However, it explains in detail.

  First, FIG. 16 attached is a side view showing the internal structure of the variable capacitance element of the present invention including its drive circuit from the side, in which “L1” is the surface of the first substrate 1. The height from the surface of the first substrate 1 to the surface of the second actuator 11 (or the lower surface of the second substrate 14) is “L2”. “D” indicates a distance from the surface of the first actuator 11 to the lower surface of the dielectric 15.

  Reference numeral 100 in the figure denotes a drive control unit that controls the entire electronic device, such as a mobile phone, on which the variable capacitance element according to the present invention is mounted. A control signal including a command for changing the capacitance of the element and a value of the capacitance to be changed is output. The drive control unit is configured by, for example, a CPU including a memory device. Reference numeral 110 in the drawing generates drive power (current or voltage: Act1, Act2) described below based on the control signal from the drive control unit 100 described above to generate the first and second actuators 11. , 12 shows a drive signal generation circuit for supplying the signal.

  By the way, an actuator (hereinafter referred to as “organic actuator”) formed by applying and curing a paste made of the above-described conductive filler and epoxy resin is expanded by, for example, energization (heating expansion) of a drive current and cooled. The organic actuator has a tendency to shrink to its original state with (stop of energization). Furthermore, after the organic actuator expands by heating and expansion, it will return (shrink) to its original state by cooling (stop of energization). However, it has a characteristic that when it is restrained in the middle and a predetermined time has passed, it remains stable (constrained height) and remains stable (held). Is called “latch function” or “latch state”.

  In the present invention, by utilizing the “latch function” or “latch state” in the organic actuator, the electrode interval can be arbitrarily set, and the capacitance of the variable capacitance element can be appropriately changed, and the power saving can be reduced. Will also be achieved at the same time. The “latch function” or “latch state” in the organic actuator can be restored to the original steady state by energization heating again.

  Attached FIG. 17 shows a drive diagram of the above-described variable capacitance element, and in the vertical axis direction, changes in the positions of the above-mentioned “L1” and “L2” which are electrode positions (heights) are shown. In the horizontal axis direction, the driving state ("ON", "OFF") of the driving current (Act2, Act1) is shown. These drive currents (Act 2, Act 1) are energized through the electrodes 3 and 4 and the electrodes 3 and 4 provided on the lower surfaces of the first and second organic actuators 11 and 12, respectively. Is done.

  First, in an initial state where no drive current is passed (Act2 = OFF, Act1 = OFF), the height of the first organic actuator 11 is “L1”, and the height of the second organic actuator 12 is “L2”. It has become. The state at this time is shown in FIG. When a driving current is passed (Act2 = ON, Act1 = ON), both organic actuators 11 and 12 are heated and expanded by self-heating. The state at this time is shown in attached FIG.

  Then, after both organic actuators 11 and 12 have expanded to a predetermined height, the first organic actuator 11 is driven appropriately to maintain its steady state (a state in which the height is maintained). A current is passed (Act1 = ON), and in this state, the drive current of the second organic actuator 12 is stopped (Act2 = OFF). As a result, the height of the first organic actuator 11 becomes a steady state and maintains a predetermined height, while the second organic actuator 12 cools and contracts to reduce its height. In the middle of this, the function of the first organic actuator 11 that maintains the steady state (specifically, the lower surface of the dielectric 15 abuts on the upper surface of the first organic actuator 11 to stop the contraction). In other words, by continuing this state for a predetermined time, the second organic actuator 12 enters the “latch state” and maintains its height (stable) thereafter. The state at this time is shown in FIG.

  Next, energization to the first organic actuator 11 is stopped (Act1 = OFF). As a result, the first organic actuator 11 is cooled and contracts, and then returns to the initial state and becomes a steady state. At this time as well, the second organic actuator 12 is in a “latched state” and maintains its height stably. The state at this time is shown in FIG.

  As a result, the distance “D” from the surface of the first actuator 11 to the lower surface of the dielectric 15 (see FIG. 16) is not only the height of the first actuator 11 but also the dielectric 15 In other words, the distance “D” is the height of the first organic actuator 11 in the initial state (steady state). And the height of the second organic actuator 12 in the “latch state” is determined by the height of the second organic actuator 12 in the “latch state”. It becomes variable depending on the height of the actuator 11 in the steady heating state.

  That is, according to the variable capacitance element of the present invention and the control method therefor, the distance “D” can be set arbitrarily and arbitrarily according to the energization pattern to the first and second organic actuators 11 and 12. Thus, the capacitance of the variable capacitance element can be freely changed with a relatively simple configuration.

  In FIG. 18, the distance “D” from the surface of the first actuator 11 to the lower surface of the dielectric 15 is shown enlarged for the description. However, since this distance “D” is in units of microns, and the surface of the dielectric 15 is uneven (rough surface), the change in the capacitance of the variable capacitance element is actually In this case, the contact region between the surface of the dielectric 15 and the surface of the actuator 11 is brought about by a change.

  In addition, in the state after the capacitance is variably set as described above, the drive current to both the organic actuators 11 and 12 is unnecessary (Act2 = OFF, Act1 = OFF). After changing the capacitance, there is no power consumption. Therefore, the variable capacitance element of the present invention is suitable for power saving and low power consumption operation. Furthermore, as described above, the organic actuators 11 and 12 that are self-heating type actuators constitute the element, so that degassing is performed as needed by heating during driving (capacity change). In other words, since the adsorbed material such as moisture that is easily adsorbed on the electrode surface can be desorbed by heating the actuator, it is possible to suppress moisture adsorption and the like, thereby reducing the risk of sticking and electrode corrosion. Will be.

  Regarding the subsequent reset operation, the second organic actuator 12 is energized again to perform thermal expansion (Act2 = ON), and thereafter, the energization of the drive current is stopped to cool and contract, thereby stabilizing the steady state. Return to. At this time, the first organic actuator 11 is already in a steady state, and the drive current is not supplied. As described above, the pattern of the drive current supplied to the first and second organic actuators 11, 12 (its shape, current value, etc.) includes a desired static value including the distance “D”. From the relationship with the electric capacity, it can be easily obtained by the drive signal generation circuit 110 by actually obtaining it in advance by experiments or the like and storing it in the memory device of the drive control unit 100 described above. It is possible to generate. Alternatively, instead of the above, it is also possible to store various patterns in the drive signal generation circuit 110 and appropriately select and output them based on the capacitance value to be changed in the control signal.

  In addition, according to the variable capacitance element described above, a dielectric formed by a coating (printing) process is provided, and as described above, electrostatic control is performed by controlling the surface contact pressure between the electrode and the dielectric. In the structure in which the capacitance is variable, the dielectric layer 15 is formed on one substrate, and the first and second organic actuators 11 and 12 are formed on the other substrate. The member can also be used as a protective film (spacer). According to such a configuration, particularly when a large number of variable capacitance elements are manufactured at a time using a relatively large substrate, the variable capacitance elements can be stably manufactured by a printing process.

  The variable capacitance element having a cantilever structure has been described above as an example. However, the present invention can also be applied to variable capacitance elements having other structures. A variable capacitance element according to a second embodiment (embodiment 2) of the present invention in which a second organic actuator 22 having a “U” shape is formed surrounding the periphery of the organic actuator 21 will be described.

  First, FIG. 19 and FIG. 20 attached show a top view and a side view of a variable capacitor according to the second embodiment. In particular, as can be seen from FIG. 19, a plurality of electrode layers 23, 24, 25, and 26 are formed on the upper surface of the first substrate (main substrate) 1, and are arranged in the central portion thereof. The first actuator 21 is formed so as to straddle the pair of electrodes 23 and 24, and the “U” -shaped second actuator 22 is formed so as to surround the periphery of the first actuator 21. Has been. On the other hand, as is apparent from FIG. 20, the electrode layer 27 is formed on the lower surface of the second substrate (sub-substrate) 14, and the dielectric layer 15 is formed at the substantially central portion thereof. The second substrate 14 is bonded so as to face the upper surface of the first substrate 1.

  In particular, as is apparent from FIG. 20, in the variable capacitance element according to the second embodiment, the pattern signal from the drive signal generation circuit 110 described above, that is, the drive signals (Act1, Act2), It is supplied to the electrode 26. An arbitrary variable capacitance is obtained (formed) between the electrode 23 and the electrode 26, as is apparent from the drawing.

  In the variable capacitance element according to the second embodiment, unlike the cantilever structure of the first embodiment, the second substrate (sub-substrate) 29 is connected to the second organic actuator 22 having a “U” shape. The distance “D” can be arbitrarily set by displacing the electrode 27 and the dielectric layer 15 provided on the lower surface thereof in the vertical axis direction. However, other effects obtained thereby are as follows. This is almost the same as described above, and a description thereof is omitted here.

  In the variable capacitor according to the second embodiment, the first and second organic actuators for making the distance “D” variable, in particular, the second organic actuator 22, and the first organic actuator 21 are used. The so-called double-structured actuator is used as an external seal, so that foreign matter can be mixed. It becomes possible to prevent.

  In addition, as can be seen from the above, in the variable capacitance element according to the second embodiment, the “U” -shaped actuator 22 is arranged around the outer periphery of the first actuator 21 to arrange the first embodiment. It is possible to configure without using a conductive adhesive as in 1. In the variable capacitance element according to the second embodiment, the materials of these members are the same as those in the above-described embodiment, and therefore detailed description thereof is omitted here. The detailed operation is also the same as that of the third embodiment shown below, and is omitted here.

  Subsequently, attached FIGS. 21 to 23 show a method of manufacturing a variable capacitance element according to the third embodiment (embodiment 3) of the present invention. In particular, FIGS. 21A to 21D show the manufacturing process on the fixed electrode side centered on the first substrate (main substrate) 1, and FIGS. 22A and 22B show the second step. The manufacturing process on the movable electrode side centering on the substrate (sub-substrate) 29, and FIGS. 23A and 23B are the first substrate 1 (main substrate: movable electrode side) and the second substrate. Each of the manufacturing steps for attaching and assembling 14 (sub-substrate: fixed electrode side) is illustrated. In these drawings, the same reference numerals as those in the first embodiment denote the same components in the first embodiment.

  First, as shown in the attached FIG. 21A, on the fixed electrode side centering on the first substrate (main substrate) 1, a plurality of surfaces are formed on the upper surface of the first substrate (main substrate) 1. Electrode layers 33, 34, 35, and 36 are formed. At this time, the electrode is formed by preparing an insulating substrate with a metal foil (for example, copper foil) on its surface, etching, mask vapor deposition, selective plating, or the like. A formation method by direct application drawing with ink or paste using nanoparticles is adopted.

  As shown in FIG. 21 (b), an insulator is applied on one (front) side of the electrodes 33 and 34 in the central portion, and the insulating film 37 is formed by baking the insulator. . Thereafter, as shown in FIG. 21 (c), on the other (rear) side of the electrodes 33 and 34 in the central portion, the paste made of the conductive filler and the epoxy resin is applied and baked by a dispenser, screen printing or the like. Thus, the first organic actuator 38 is formed. Thereafter, as shown in FIG. 21D, the paste is applied and baked in a “B” shape so as to surround the first organic actuator 38 to form a second organic actuator 39. . Thereby, the manufacture on the fixed electrode side centering on the first substrate 1 is completed.

  Next, as shown in FIG. 22A attached, on the movable electrode side centering on the second substrate (sub-substrate) 14, the electrode 40 is formed on the upper surface thereof. At this time, in the same manner as described above, an insulating substrate having a metal foil (for example, copper foil) pasted on its surface is prepared and etching method, mask vapor deposition method, selective plating method or the like is used. A forming method by direct coating drawing with ink or paste using particles is employed. After that, a dielectric layer 15 is formed by applying and baking a dielectric on the upper surface of the electrode 40 at a substantially central portion of the second substrate 14.

  Thereafter, as shown in FIG. 23A, the second substrate (sub-substrate) 14 on which the electrode 40 and the dielectric layer 15 are formed is turned over so that the formed dielectric layer 15 faces downward (see FIG. Then, as shown in FIG. 23B, the second substrate (sub substrate) 14 turned upside down is bonded so as to face the upper surface of the first substrate (main substrate) 1. Bake.

  Subsequently, FIG. 24 attached is a side view showing the internal structure of the variable capacitance element from its side, and in the variable capacitance element shown in this figure as well as in the first embodiment, the drive signal generation described above is performed. Based on the drive power (current or voltage: Act1, Act2) supplied from the circuit 110, the first organic actuator 38 and the second organic actuator 39 are driven and displaced, whereby the electrodes 34 and 34 The capacitance formed during the period is changed. Also in this embodiment, by utilizing the “latch function” or “latch state” in the organic actuator, the electrode interval can be arbitrarily set, and the capacitance of the variable capacitance element can be appropriately varied. The achievement of power saving at the same time is the same as in the first embodiment.

  As shown in the drive diagram of the variable capacitance element shown in FIG. 25, first, in the initial state where no drive current flows (Act2 = OFF, Act1 = OFF), the height of the first organic actuator 38 Is “L1”, and the height of the second organic actuator 39 is “L2”. When a driving current is passed (Act2 = ON, Act1 = ON), both organic actuators are heated and expanded by self-heating.

  Thereafter, after both organic actuators 38 and 39 have expanded to a predetermined height, the first organic actuator 38 has an appropriate driving current for maintaining a steady state (a state in which the height is maintained). In this state, the driving current of the second organic actuator 39 is stopped (Act2 = OFF). As a result, the height of the first organic actuator 38 is in a steady state and maintains a predetermined height, while the second organic actuator 39 is cooled and contracted to reduce its height. In the middle of this, the action of the first organic actuator 38 that maintains the steady state (specifically, the contraction of the dielectric 15 is stopped when the lower surface of the dielectric 15 contacts the upper surface of the first organic actuator 38). In other words, by continuing this state for a predetermined time, the second organic actuator 39 enters the “latch state” and maintains its height (stable) thereafter. .

  Further, the energization to the first organic actuator 38 is stopped (Act1 = OFF). As a result, the first organic actuator 38 is cooled and contracted, and then returns to the initial state and becomes a steady state. At this time as well, the second organic actuator 39 is in a “latched state” and maintains its height stably.

  As described above, also in the third embodiment, the distance “D” is equal to the height of the first organic actuator 38 in the initial state and the second organic actuator, as in the first and second embodiments. 39 is determined by the height in the “latch (stable) state” of 39, and the height in the “latch state” of the second organic actuator 39 is the heating steady state of the first organic actuator 38. Depends on the height in the state, it becomes variable. That is, the distance “D” can be arbitrarily set arbitrarily according to the energization pattern to the first and second organic actuators 38 and 39 also by the variable capacitance element of the present embodiment and the control method therefor. Thus, the capacitance of the variable capacitance element can be freely changed with a relatively simple configuration. In addition, in the state after the capacitance has been variably set, the drive current to both organic actuators is not required. Therefore, once the capacitance has been changed, there is no power consumption. It is also suitable for power saving and low power consumption operation.

  In the variable capacitance element according to the third embodiment, the first and second organic actuators for making the distance “D” variable, in particular, the second organic actuator 39, and the first organic actuator 38 are used. The so-called double-structured actuator is used as an external seal, so that foreign matter can be mixed. It becomes possible to prevent.

  In addition, the variable capacitance element according to the third embodiment also has a structure formed by a coating process as in the first embodiment, and the dielectric layer 15 formed on the electrode surface of one substrate or the like. Needless to say, when the organic actuator formed on the other substrate is used as a spacer in the sealing process, it can be easily manufactured by a printing process. In particular, when a large number of variable capacitance elements are manufactured at a time using a relatively large substrate, the variable capacitance elements can be stably manufactured by a printing process.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an overall structure of a cantilever type variable capacitance element according to a first embodiment (Example 1) of the present invention. It is a side view for showing the internal structure of the cantilever type variable capacitance element. It is the perspective view which notched and showed the internal structure of the said cantilever type variable capacitance element in order to make it intelligible. It is the top view which looked at the above-mentioned cantilever type variable capacity element from the upper part. It is a perspective view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a top view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a perspective view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a top view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a perspective view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a top view which shows the manufacturing process of the 1st board | substrate (main board | substrate) of the said cantilever type variable capacitance element. It is a perspective view which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) of the said cantilever type variable capacitance element. It is a top view which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) of the said cantilever type variable capacitance element. It is a perspective view which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) of the said cantilever type variable capacitance element. It is a top view which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) of the said cantilever type variable capacitance element. It is a perspective view which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) of the said cantilever type variable capacitance element. FIG. 4 is a side view of a variable capacitance element including a drive circuit for explaining a method of setting the capacitance of the cantilever type variable capacitance element. It is a figure which shows the drive diagram for demonstrating the setting method of the electrostatic capacitance of the said cantilever type variable capacitance element. It is a side view which shows the state of each part in the setting method of the electrostatic capacitance of the said cantilever type variable capacitance element. It is a top view which shows the structure of the variable capacity element which becomes 2nd embodiment (Example 2) of this invention. It is a side view which shows the structure of the variable capacitance element which becomes 2nd embodiment (Example 2) of this invention. It is a figure which shows the manufacturing process of the 1st board | substrate (main board | substrate) especially of the variable capacitance element which becomes 3rd Example (Example 3) which becomes this invention. It is a figure which shows the manufacturing process of the 2nd board | substrate (sub board | substrate) especially of the variable capacitance element which becomes 3rd Example (Example 3) which becomes this invention. It is a figure which shows the manufacturing process assembled with the 1st board | substrate (movable electrode side) and the 2nd board | substrate (fixed electrode side) in the variable capacitance element of the said Example 3. FIG. FIG. 6 is a side view of a variable capacitance element including a drive circuit for explaining a method for setting the capacitance of the variable capacitance element according to the third embodiment. It is a figure which shows the drive diagram for demonstrating the setting method of the electrostatic capacitance of the variable capacitance element of the said Example 3. FIG.

Explanation of symbols

1 First board (main board)
2, 3, 4, 5, 6 Electrode (layer)
11 First actuator (layer)
12 Second actuator (layer)
14 Second substrate (sub-substrate)
15 Dielectric layer.

Claims (8)

Two opposing substrates,
Electrodes respectively formed on opposing surfaces of the two opposing substrates;
And a dielectric layer provided on the surface of one of the two opposed electrodes, and a capacitance that forms a capacitance by the two opposed electrodes and the dielectric layer disposed therebetween An element, and
Between the two board to the opposite, at least, an organic actuator member so as to form two organic actuators obtained by forming a layer, the driving electrode for supplying driving power to the organic actuators respectively Provided ,
When driving power is supplied to one of the two organic actuators and extended, the driving power is supplied to one organic actuator and the driving power to the other organic actuator is stopped, The variable capacitance element is configured so that contraction is restrained by the one organic actuator, and the other organic actuator is stabilized in the restrained extended state . In the variable capacitance element described in 請 Motomeko 1,
The organic actuator before Symbol hand, the is formed on a surface of the other electrode of the two electrodes, organic actuator before Symbol other hand, during the two board to the counter, said one of the organic A variable capacitance element provided adjacent to an actuator. In the variable capacitance element described in 請 Motomeko 2,
The other organic actuator is formed so as to surround the one organic actuator. Prepare two opposing substrates,
Forming electrode layers on opposite surfaces of the two substrates,
On the opposing surface of one of the two substrates, two organic actuators formed by forming an organic actuator material in layers are formed, and on the opposing surface of the other substrate of the two substrates, Forming a dielectric layer on the surface of the formed electrode;
The two substrates are bonded together so that the dielectric layer formed on the opposite surface of the other substrate faces the electrode layer formed on the opposite surface of the one substrate. A variable capacitance element manufacturing method, characterized in that a variable capacitance element having a variable capacitance formed by two electrode layers and the dielectric layer disposed therebetween is manufactured. In the manufacturing method of the variable capacitor as described in 請 Motomeko 4,
One of the two organic actuators is formed by a film forming method, and the method of manufacturing a variable capacitance element. Two opposing substrates, electrodes formed on opposing surfaces of the two opposing substrates, and a dielectric layer provided on one electrode surface of the two opposing electrodes cage, a capacitor element to form the electrostatic capacitance by the two electrodes and the dielectric layer disposed between them to the counter, further, between the two board to the opposite, at least, organic actuator member A method of setting the capacitance of a variable capacitance element, in which two organic actuators formed in layers are formed and provided with driving electrodes for supplying driving power to the organic actuators,
Drive and displace both of the two organic actuators,
One organic actuator of the two organic actuators is set in a steady state to set the position of the other organic actuator,
By the this setting the position of the one organic actuators, the capacitance setting of the variable capacitance element, characterized in that the electrostatic capacitance is variably set. In the electrostatic capacitance setting method described in 請 Motomeko 6,
When setting the position of the other organic actuators, and at the same time the one organic actuator of supplying driving power required to maintain the steady-state, stopping the drive power to the front SL other organic actuator A capacitance setting method for a variable capacitance element. In the electrostatic capacitance setting method described in 請 Motomeko 7,
When setting the position of the one organic actuator, the supply of drive power to the one organic actuator is stopped and returned to the initial state.

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