JP4513327B2 - Piezoelectric resonance component - Google Patents

Description

  The present invention relates to a load resonance type piezoelectric resonance component including an energy confinement type piezoelectric resonance element and a capacitor element, and more specifically, a piezoelectric element having a structure in which a capacitor element and a piezoelectric resonance element are stacked on a substrate. Resonant parts.

  Conventionally, various load capacitance built-in piezoelectric oscillators having a structure in which a capacitor element and a piezoelectric resonance element are laminated on a substrate have been proposed. For example, the following Patent Document 1 discloses a piezoelectric resonant component shown in FIGS.

  As shown in FIG. 10, in the piezoelectric resonant component 101, a package is constituted by a rectangular plate-like insulating substrate 102 and a case 103 having an opening opened downward. A plurality of electrodes 104 a to 104 c are formed on the upper surface of the insulating substrate 102. Capacitor element 106 is mounted on electrodes 104a-104c using conductive adhesives 105a-105c.

  The capacitor element 106 is a three-terminal capacitor. Capacitance electrodes 106b and 106c are formed on the upper surface of the elongated strip-shaped dielectric substrate 106a. A common electrode 106d is formed at the center of the lower surface. The capacitive electrodes 106b and 106c and the common electrode 106d are opposed to each other through the dielectric substrate 106a.

  The conductive adhesives 105a and 105c electrically connect the electrode extension portions of the first capacitive electrodes 106b and 106c reaching the lower surface of the dielectric substrate and the electrodes 104a and 104c. In addition, the conductive adhesive 105b electrically connects the common electrode 106d and the electrode 104b.

  On the capacitor element 106, an energy confinement type piezoelectric resonance element 108 is fixed via conductive adhesives 107a and 107b. The piezoelectric resonant element 108 has an elongated strip-shaped piezoelectric substrate 109. A first vibration electrode 110 is formed on the upper surface of the piezoelectric substrate 109, and a second vibration electrode 111 is formed on the lower surface. The portion where the vibrating electrodes 110 and 111 are opposed constitutes an energy trapping type piezoelectric vibrating portion.

  The second vibrating electrode 111 is electrically connected to the capacitor electrode 106b by the conductive adhesive 107a. The first vibrating electrode 110 has an electrode extension 110 a that extends from the end surface of the piezoelectric substrate 109 to the lower surface. The electrode extension 110a is electrically connected to the capacitive electrode 106c by the conductive adhesive 107b.

  Therefore, in the piezoelectric resonance component 101, as shown in FIG. 11, a load oscillation type piezoelectric oscillation circuit in which two capacitances are connected to the piezoelectric resonance element is configured.

The case 103 is made of metal and bonded onto the substrate 102 using an insulating adhesive 112.
JP-A-8-307193

  The piezoelectric resonant component 101 is required to set the oscillation frequency with high accuracy. Therefore, conventionally, prior to preparing the piezoelectric resonant element 108, the resonant frequency of the piezoelectric resonant element 108 has been adjusted by trimming or the like by laser light irradiation.

  However, even if the frequency characteristics of the piezoelectric resonance element 108 are adjusted, when the capacitor element 106 and the piezoelectric resonance element 108 are stacked on the substrate 102 as described above, the frequency characteristics are desired due to variations in the mounting structure. There was a case where it deviated from the frequency characteristics.

  Therefore, the inventors of the present application examined trimming the vibrating electrode 110 by irradiating an ion beam or a laser beam from above when the capacitor element 106 and the piezoelectric resonant element 108 were mounted on the substrate 102. In this case, trimming is performed after mounting to adjust the frequency. Therefore, the frequency of the final piezoelectric resonant component 101 can be controlled with higher accuracy.

  By the way, in order to efficiently adjust the frequency, it is desirable to irradiate the vibrating electrode 110 with an ion beam or a laser beam using a large-diameter ion gun or a laser light source.

  However, when an ion beam or laser light is irradiated from above using a large-diameter ion gun or laser light source, the ion beam or laser light also reaches the lower side of the vibrating electrode 110. Therefore, the ion conductive beam 105b is also irradiated with the conductive adhesive 105b.

  That is, as shown in FIG. 12, when the capacitor element 106 is bonded onto the substrate 102 using the conductive adhesives 105a to 105c, the conductive adhesives 105a to 105c press the capacitor element 106 against the substrate 102 side. At that time, the film was spread and tended to spread to the outside of both side surfaces of the dielectric substrate 106a. FIG. 13 is a cross-sectional view schematically showing a joint portion by the conductive adhesive 105b having the structure shown in FIG.

  As is apparent from FIGS. 12 and 13, the conductive adhesive 105b is spread when the capacitor element 106 is bonded to the substrate 102, and spreads outside the side surfaces 106a1 and 106a2 of the dielectric substrate 106a. Therefore, an ion beam or the like irradiated from above reaches the conductive adhesive 105b.

  The conductive adhesive 105b has a composition in which conductive powder such as Ag is mixed in an insulating adhesive. Therefore, when the ion beam or the like is applied to the conductive adhesive 105b, the Ag powder is scattered and may adhere to the side surfaces of the capacitor element 106 and the piezoelectric resonance element 108, and the electrodes on both sides may be short-circuited.

  In order to avoid the above-described problem, the ion beam or the like that is irradiated when adjusting the frequency is applied to only a part of the vibrating electrode 110, in particular, the ion beam or the like so that the ion beam or the like is not irradiated outward from the side surface of the piezoelectric resonance element 108. It is thought that it is sufficient to irradiate. However, when an ion beam or the like is applied only to a part of the vibrating electrode 110, undesired spurious may appear on the frequency characteristics.

  The object of the present invention is to allow the frequency adjustment with high accuracy in a state close to the mounting structure by irradiation with an ion beam or laser light in view of the above-described state of the prior art, and to prevent a short circuit failure or deterioration of characteristics. An object of the present invention is to provide a piezoelectric resonant component that is less likely to cause unwanted spurious and is excellent in reliability.

According to a first aspect of the present invention, there is provided a piezoelectric resonant component comprising: a substrate having a plurality of electrodes provided on an upper surface; a capacitor element bonded to the substrate with a conductive adhesive; and a conductive adhesive on the capacitor element. A piezoelectric resonator element mounted on the dielectric substrate, wherein the capacitor element is opposed to the dielectric substrate, a common electrode provided on a lower surface of the dielectric substrate, and the common electrode through the dielectric substrate. A plurality of capacitive electrodes provided on the upper surface of the dielectric substrate, the capacitive electrode having an electrode extension extending from the end surface of the dielectric substrate to the lower surface, and an electrode of the capacitive electrode The extension portion and the common electrode are each electrically connected to the plurality of electrodes on the substrate by the conductive adhesive, and the piezoelectric resonant element is partially connected to the piezoelectric substrate and the upper and lower surfaces of the piezoelectric substrate. Formed in And the first and second vibrating electrodes provided so as to face each other through the piezoelectric substrate, and the portion where the first and second vibrating electrodes are opposed is an energy confining type vibrating portion. A conductive adhesive that is directly below the portion where the first and second vibrating electrodes are opposed and electrically connects the common electrode of the capacitor element and the electrode of the substrate; wherein the portion disposed a recess on the lower surface of the dielectric substrate is formed, the previous SL common electrode is formed to extend in the recess, wherein said conductive adhesive remains in the recess And
A second invention of the present application is mounted on a substrate having a plurality of electrodes provided on the upper surface, a capacitor element bonded to the substrate with a conductive adhesive, and a conductive adhesive on the capacitor element. A piezoelectric resonant element, wherein the capacitor element is a dielectric substrate, a common electrode provided on a lower surface of the dielectric substrate, and the dielectric substrate so as to face the common electrode through the dielectric substrate. A plurality of capacitance electrodes provided on the upper surface, and the capacitance electrode has an electrode extension extending from the end surface of the dielectric substrate to the lower surface, and the electrode extension of the capacitance electrode and the common electrode Are electrically connected to the plurality of electrodes on the substrate by the conductive adhesive, and the piezoelectric resonant element is partially formed on the piezoelectric substrate and the upper and lower surfaces of the piezoelectric substrate. And a piezoelectric substrate And the first and second vibrating electrodes provided so as to face each other, and the portion where the first and second vibrating electrodes are opposed constitutes an energy confining type vibrating portion, Immediately below the portion where the first and second vibrating electrodes are opposed to each other, on the portion where the conductive adhesive electrically connecting the common electrode of the capacitor element and the electrode of the substrate is disposed A recess is formed on the lower surface of the dielectric substrate, and the recess has a pair of notches extending from a pair of opposing side surfaces of the dielectric substrate to the center in the width direction, and the pair of notches In the meantime, a flat portion connected to the remaining lower surface portion of the dielectric substrate is provided, the common electrode reaches the flat portion, and the conductive adhesive remains in the recess. Features .

In a specific aspect of the piezoelectric resonant component according to the first invention, the recess has a pair of notches extending from a pair of opposing side surfaces of the dielectric substrate to the center in the width direction, A flat portion connected to the remaining lower surface portion of the dielectric substrate is provided between the cutout portions.

In still another specific aspect of the piezoelectric resonant component according to the first invention, the concave portion is provided so as to reach the entire width of the lower surface of the dielectric substrate.

In still another specific aspect of the piezoelectric resonant component according to the first invention, the concave portion includes a bottom portion and a pair of inclined surface portions that are connected to the lower surface of the dielectric substrate from both sides of the bottom portion. The inclined surface portions of the dielectric substrate are inclined so as to move away from each other toward the lower surface of the dielectric substrate, and the common electrode is provided so as to reach the lower surface portion of the dielectric substrate connected to the concave portion from the concave portion. .

  In another specific aspect of the piezoelectric resonant component according to the present invention, the piezoelectric resonance component further includes a case attached to the substrate and having an opening below, and in a sealed space formed by the substrate and the case, The capacitor element and the piezoelectric resonance element are sealed.

  In the present invention, in a structure in which a capacitor element is bonded onto a substrate using a conductive adhesive and a piezoelectric resonant element is mounted on the capacitor element using a conductive adhesive, a common electrode of the capacitor element, A concave portion is formed on the lower surface of the dielectric substrate in a portion where the conductive adhesive that electrically connects the electrode of the substrate is provided. Therefore, when the capacitor element is bonded to the substrate using the conductive adhesive, the common electrode and the electrode on the substrate are bonded by the conductive adhesive in the recess in the portion where the common electrode is provided. .

  Therefore, even if a force is applied so that the capacitor element can be brought close to the substrate, the conductive adhesive remains in the recess.

  That is, it is difficult for the conductive adhesive to spread outward from the side surface of the dielectric substrate constituting the capacitor element. Therefore, the first vibrating electrode on the upper surface of the piezoelectric resonant element is irradiated with an ion beam or the like from above the piezoelectric resonant element above the joint portion of the conductive adhesive joining the common electrode to the electrode of the substrate. Even if the frequency is adjusted so as to trim, the ion beam or the like does not reach the joint portion formed by the conductive adhesive. Therefore, frequency adjustment can be performed by efficiently irradiating an ion beam or laser light using a large-diameter ion gun or a laser light source. In addition, since the conductive powder in the conductive adhesive is not easily scattered by an ion beam or the like, it is difficult to cause deterioration of characteristics due to short circuit failure.

  Therefore, in the piezoelectric resonant component according to the present invention, frequency adjustment can be performed with high accuracy in a state close to a completed piezoelectric resonant component in which a capacitor element and a piezoelectric resonant element are laminated on a substrate using a conductive adhesive. In addition, it is possible to stably provide a piezoelectric resonant component in which deterioration of characteristics and short-circuit failure due to scattering and adhesion of components of the conductive adhesive hardly occur.

  The recess has a notch extending from the pair of opposing side surfaces toward the center in the width direction on the lower surface of the dielectric substrate, and the remaining upper surface of the dielectric substrate is interposed between the pair of notches. When the flat part connected with the part is provided, a conductive adhesive is reliably accommodated in a notch part. In addition, the conductive adhesive is firmly pressed against the common electrode and the electrode of the substrate at the flat portion between the pair of notches. Therefore, the reliability of the electrical connection of the joint portion by the conductive adhesive can be improved.

  In the case where the recess is provided so as to reach the entire width of the lower surface of the dielectric substrate, it is possible to effectively prevent the joint portion from spreading from the side surface of the dielectric substrate to the outside by the conductive adhesive. . Further, the recess can be easily formed on the lower surface of the dielectric substrate.

  The recess has a bottom portion and a pair of inclined surface portions connected to the lower surface of the dielectric substrate from both sides of the bottom portion, and the pair of inclined surface portions are inclined so as to move away from each other toward the lower surface of the dielectric substrate. When the common electrode is provided so as to extend from the concave portion to the lower surface portion of the dielectric substrate connected to the concave portion, the conductive adhesive is securely stored in the concave portion, and the disconnection in the concave portion of the common electrode is prevented. The fear can be reduced.

  In the piezoelectric resonance component according to the present invention, when the case further includes a case attached to the substrate and having an opening below, the capacitor element and the piezoelectric resonance element are disposed in a sealed space formed by the substrate and the case. Sealed. Accordingly, it is possible to provide a piezoelectric resonant component having excellent environmental resistance characteristics.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

  FIG. 1 is an exploded perspective view of the piezoelectric resonant component according to the first embodiment of the present invention.

  In the piezoelectric resonant component 1, a rectangular plate-like substrate 2 is used. The substrate 2 is made of an insulating ceramic such as alumina or a synthetic resin. A package is constituted by the substrate 2 and the case 3 having an opening opened downward. In this embodiment, the case 3 is made of metal. But you may be comprised with insulating materials, such as a synthetic resin and ceramics. When the case 3 is made of metal, the internal space can be electromagnetically shielded by the case 3, which is desirable. Electrodes 4 a to 4 c are formed on the upper surface of the substrate 2. The electrodes 4a to 4c are provided so as to reach not only the upper surface 2a of the substrate 2 but also the lower surface 2d through a pair of side surfaces 2b and 2c. In the present embodiment, the electrodes 4 a to 4 c are provided so as to wind the substrate 2.

  The electrodes 4a to 4c are used as external terminals for mounting the piezoelectric resonant component 1 on a printed circuit board or the like.

  Capacitor element 6 is mounted on upper surface 2a of substrate 2 using conductive adhesives 5a to 5c. The conductive adhesives 5a to 5c are configured, for example, by adding conductive powder such as Ag in an epoxy adhesive.

  The capacitor element 6 has a rectangular plate-like elongated dielectric substrate 6a. On the upper surface of the dielectric substrate 6a, the first capacitor electrodes 6b and 6c are arranged with a predetermined gap at the center of the upper surface of the dielectric substrate 6a. The first capacitor electrodes 6b and 6c have electrode extensions 6b1 and 6c1 that extend from the end surface of the dielectric substrate to the lower surface.

  In addition, a common electrode 6d as a second capacitor electrode is formed on the lower surface of the dielectric substrate 6. The common electrode 6d is opposed to the capacitive electrodes 6b and 6c through the dielectric substrate 6a. That is, the capacitor element 6 is a three-terminal capacitor having two capacitance extraction portions.

  The conductive adhesive 5 a is electrically connected to the electrode extension 6 b 1 of the capacitive electrode 6 b and the electrode 4 a formed on the substrate 2.

  The conductive adhesive 5 b electrically connects the common electrode 6 d and the electrode 4 b of the substrate 2. The conductive adhesive 5 c electrically connects the electrode extension 6 c 1 of the capacitive electrode 6 c and the electrode 4 c provided on the substrate 2.

  The feature of this embodiment is that the capacitor element 6 is provided with a recess 6e on the lower surface of the dielectric substrate 6a.

  FIG. 2 is a perspective view of the capacitor element 6 as viewed from the lower surface side. 3A and 3B are a front view and a bottom view of the capacitor element 6, respectively.

  A recess 6 e is provided on the lower surface of the capacitor element 6. Here, the recessed part 6e is comprised from a pair of notch parts 6f and 6f. The notches 6f and 6f are configured to extend from the side surfaces 6a1 and 6a2 of the dielectric substrate 6a toward the center, respectively. A flat portion 6g is provided between the pair of notches 6f and 6f. The flat portion 6g is connected to the remaining lower surface portion of the dielectric substrate 6a. That is, the flat portion 6g is provided so as to be located in the same plane as the remaining lower surface portion.

  The common electrode 6d is not provided in the notches 6f and 6f. However, the common electrode 6d may be provided so as to reach the notches 6f and 6f.

  When the capacitor element 6 is mounted on the substrate 2, the conductive adhesives 5a to 5c are applied to part of the electrode extension 6b1, the common electrode 6d, and the electrode extension 6c1, and the electrodes 4a to 4 on the substrate 2 are applied. This is done by pressing toward 4c. Alternatively, bonding may be achieved by applying conductive adhesives 5a to 5c on the electrodes 4a to 4c on the substrate 2 and pressing the capacitor element 6 from above. In this way, the capacitor element 6 is mounted on the substrate 2 as shown in FIG. FIG. 5 is a cross-sectional view of the structure shown in FIG.

  As apparent from FIGS. 4 and 5, when the capacitor element 6 is fixed to the substrate 2 by the conductive adhesives 5 a to 5 c, the conductive adhesives 5 a to 5 c are expanded. In this case, the conductive adhesives 5a and 5c are spread so as to reach the outside of the side surface of the dielectric substrate, similarly to the conductive adhesives 105a to 105c in the conventional piezoelectric resonant component.

  On the other hand, since the recess 6e having the notches 6f and 6f is provided, the central conductive adhesive 5b is accommodated in the notches 6f and 6f. Therefore, the conductive adhesive 5b does not protrude outside the side surfaces 6a1 and 6a2 of the dielectric substrate 6.

  In other words, the recess 6e formed of the notches 6f and 6f has a size capable of suppressing the protrusion of the conductive adhesive 5b to the outside of the side surfaces 6a1 and 6a2.

  Therefore, even if an ion beam or laser light is irradiated from above from above the piezoelectric resonator element 8 described later, the conductive adhesive 5b is not irradiated with the ion beam or laser light at the joint portion with the conductive adhesive 5b. .

  Returning to FIG. 1, a piezoelectric resonant element 8 is laminated on the capacitor element 6 by conductive adhesives 7a and 7b. The conductive adhesives 7a and 7b can be made of the same material as the conductive adhesives 5a to 5c.

  In this embodiment, the piezoelectric resonant element 8 is an energy confinement type piezoelectric resonant element using a thickness shear vibration mode. However, a piezoelectric resonant element using another vibration mode such as a thickness longitudinal mode other than the thickness shear mode may be used.

  The piezoelectric resonant element 8 has an elongated strip-shaped piezoelectric substrate 9. A first vibration electrode 10 is formed on the upper surface of the piezoelectric substrate 9, and a second vibration electrode 11 is formed on the lower surface. The first vibrating electrode 10 has an electrode extension 10 a that reaches the lower surface through the end surface of the piezoelectric substrate 9.

  The piezoelectric substrate 9 is made of piezoelectric ceramics polarized in the length direction. The vibrating electrodes 10 and 11 are opposed to each other at the center in the length direction of the piezoelectric substrate 9. The portion where the vibrating electrodes 10 and 11 are opposed constitutes an energy confining type piezoelectric vibrating portion. Below the piezoelectric vibration portion, a joint portion by the above-described conductive adhesive 5b is provided. However, since the conductive adhesive 5b is housed in the recess 6e of the dielectric substrate 6a as described above, it does not protrude outside the side surfaces 6a1 and 6a2 of the dielectric substrate 6a.

  On the other hand, an insulating adhesive 12 is applied in a rectangular frame shape on the upper surface of the substrate 2, and the case 3 is bonded to the substrate 2 using the insulating adhesive 12.

  As the insulating adhesive 12, an appropriate insulating adhesive such as an epoxy adhesive can be used.

  The electrodes 4 a to 4 c provided on the substrate 2, the capacitive electrodes 6 b and 6 c and the common electrode 6 d in the capacitor element 6, and the vibrating electrodes 10 and 11 in the piezoelectric resonance element 8 are appropriately made of Ag, Al, Cu, or an alloy thereof. The metal material may be used. In addition, these electrode films may have a structure in which a plurality of metal films are stacked.

  In the piezoelectric resonant component 1 of the present embodiment, in order to perform frequency adjustment with high accuracy, as described above, a stage in which the capacitor element 6 is mounted on the substrate 2 and the piezoelectric resonant element 8 is joined is obtained. Therefore, it is desirable to perform the irradiation by irradiating an ion beam or laser light from above. In this case, since the frequency adjustment is performed in a state close to the completed product of the piezoelectric resonant component 1, the frequency can be adjusted with high accuracy. And in this embodiment, the junction part by the conductive adhesive 5b does not protrude outside from the side surfaces 6a1 and 6a2 of the dielectric substrate 6a. Therefore, even if the ion beam or the laser beam is irradiated from above using a large-diameter ion gun or a laser light source on the portion where the vibrating electrodes 10 and 11 are opposed, the ion beam or the laser beam is applied to the conductive adhesive 5b. Is not irradiated. Therefore, the frequency can be adjusted efficiently and with high accuracy, and the above-described short circuit failure is unlikely to occur.

  In addition, in the present embodiment, the recess 6e has a pair of notches 6f and 6f, and a flat portion 6g is provided between the notches 6f and 6f. Therefore, the common electrode portion provided on the flat portion 6g is reliably pressed against the electrode 4b of the substrate 2 through the conductive adhesive 5b. Therefore, the reliability of electrical connection between the common electrode 6d and the electrode 4b by the conductive adhesive 5b is sufficient.

  In the above embodiment, the recess 6e having the pair of notches 6f and 6f and the flat portion 6g is formed on the lower surface of the capacitor element 6. However, in the present invention, the recess provided on the lower surface of the capacitor element is variously deformed. can do.

  FIGS. 6A and 6B are a perspective view and a side view showing a first modification of the capacitor element used in the present invention, and FIG. 7 shows a state in which the capacitor element is fixed on the substrate 2. It is a cross-sectional view.

  The capacitor element 26 shown in FIGS. 6A and 6B has a rectangular plate-like elongated strip-like dielectric substrate 26a. First capacitive electrodes 26b and 26c are provided on the upper surface of the dielectric substrate 26a. On the other hand, a common electrode 26d is provided at the center of the lower surface of the dielectric substrate 26a. In the present embodiment, a recess 26e extending to the full width is provided at the center in the length direction of the lower surface of the dielectric substrate 26a. The common electrode 26d is provided so as to extend from the inside of the recess 26e to the lower surface portion of the dielectric substrate 26a on both sides of the recess 26e.

  As apparent from FIGS. 6 and 7, also in this embodiment, when the common electrode 26d is joined to the electrode 4b on the substrate 2 by the conductive adhesive 5b, the conductive adhesive 5b is placed in the recess 26e. Stored. That is, the size of the recess 26e is provided so that the conductive adhesive 5b does not reach the outside of the side surfaces 26a1 and 26a2 of the dielectric substrate 26a at the joint portion by the conductive adhesive 5b.

  Thus, the recessed part provided in the lower surface of the said capacitor | condenser element in this invention may be formed so that it may reach the full width in the lower surface of a dielectric substrate.

  FIG. 8 is a perspective view for explaining another modification of the concave portion of the capacitor element. In the capacitor element 36 shown in FIG. 8, the upper surface and the lower surface are reversed. Also in the capacitor element 36, a pair of first capacitance electrodes 36b and 36c are provided on the upper surface. A common electrode 36d is provided on the lower surface of the dielectric substrate 36a. The common electrode 36d is formed so as to extend from the inside of the recess 36e provided at the center in the length direction of the dielectric substrate 36a to the lower surface portion located on both sides of the recess 36e.

  In the capacitor element 36, the recess 36e is provided so as to reach the entire width of the dielectric substrate 36a, similarly to the recess 26e shown in FIG. But the recessed part 36e has a pair of inclined surface parts 36e2 and 36e2 provided in the both sides of the bottom part 36e1 and the bottom part 36e1. The inclined surface portions 36e2 and 36e2 are inclined so as to move away from each other toward the lower surface of the dielectric substrate 36a. Accordingly, the common electrode 36d is difficult to be disconnected at the edge formed by the lower surface of the dielectric substrate 36a and the inclined surface portions 36e2 and 36e2 and at each edge formed by the inclined surface portions 36e2 and 36e2 and the bottom portion 36e1.

  Furthermore, since the inclined surface portions 36e2 and 36e2 are provided so as to move away from each other as they reach the lower surface of the dielectric substrate 36a, a large amount of conductive adhesive can be stored in the recess 36e. Therefore, the protrusion of the conductive adhesive to the outside of the dielectric substrate 36a can be more effectively suppressed.

  9A and 9B are a perspective view for explaining still another modified example of the concave portion of the capacitor element used in the present invention, and a cross-sectional view showing a state in which the capacitor element is bonded on the substrate. is there. In FIG. 9A, it is pointed out that illustration of the capacitor electrode and the common electrode is omitted for easy illustration.

  In the dielectric substrate 46a of the capacitor element 46, a recess 46e is provided at the center of the lower surface. The recess 46e is provided so as to reach the entire width of the dielectric substrate 46a as in the case of 26e shown in FIG. However, the difference is that a protrusion 46f is provided at the center of the recess 46e. The flat surface at the tip of the protrusion 46f is flush with the lower surface of the dielectric substrate 46a. In other words, the recess 46e is provided on the lower surface of the dielectric substrate 46a so as to leave the protrusion 46f. But the front end surface of the protrusion part 46f does not necessarily need to be flush with the lower surface 46a.

  In the capacitor element 46 using the dielectric substrate 46a, as shown in FIG. 9B, not only the conductive adhesive 5b is accommodated in the recess 46e, but also the presence of the protrusion 46f. As a result, the reliability of electrical connection with the common electrode 46d is improved. That is, when the common electrode 46d is provided so as to be also present on the tip surface of the protruding portion 46f, the conductive adhesive 5b is reliably pressed between the protruding portion 46f and the electrode 4b, and the electric Connection reliability is improved.

  In the embodiment and the modification described above, the capacitor element is provided below the piezoelectric resonance element provided with one piezoelectric vibration part. However, a filter element having a plurality of piezoelectric vibration parts may be used as the piezoelectric resonance element. May be used.

  Moreover, it is not limited to what has the package structure which consists of the case 3 and the board | substrate 2, The case 3 does not need to be provided. Further, other case materials in place of the case 3 may be used.

The disassembled perspective view of the piezoelectric resonant component which concerns on one Embodiment of this invention. The perspective view seen from the lower surface side of the capacitor | condenser element used by embodiment shown in FIG. (A) And (b) is the top view and bottom view of the capacitor | condenser element which were shown in FIG. The perspective view which shows the state which mounted the capacitor | condenser element on the board | substrate in the piezoelectric resonance component shown in FIG. FIG. 5 is a cross-sectional view of the structure shown in FIG. 4. (A) And (b) is the perspective view and side view for demonstrating the 1st modification of the capacitor | condenser element used by this invention. 7 is a cross-sectional view of a structure in which the capacitor element shown in FIGS. 6A and 6B is mounted on a substrate. FIG. The perspective view seen from the lower surface side of the capacitor | condenser element for demonstrating the 2nd modification of the capacitor | condenser element used by this invention. (A) And (b) is the perspective view seen from the lower surface side of the dielectric substrate for demonstrating the further another modification of the capacitor | condenser element used by this invention, and the crossing of the structure which mounted this capacitor | condenser element on a board | substrate. Plan view. The exploded perspective view of the conventional piezoelectric resonance component. The figure which shows the circuit structure of the piezoelectric resonance component shown in FIG. The perspective view which shows the state which mounted the capacitor | condenser element on the board | substrate in the case of manufacture of the piezoelectric resonance component shown in FIG. FIG. 13 is a cross-sectional view of the structure shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Piezoelectric resonance component 2 ... Board | substrate 2a ... Upper surface 2b, 2c ... Side surface 2d ... Lower surface 3 ... Case 4a-4c ... Electrode 5a-5c ... Conductive adhesive 6 ... Capacitor element 6a ... Dielectric substrate 6a1, 6a2 ... Side surface 6b , 6c ... 1st capacitance electrode 6b1, 6c1 ... Electrode extension 6d ... Common electrode 6e ... Recess 6f ... Notch 6g ... Flat part 7a, 7b ... Conductive adhesive 8 ... Piezoelectric resonance element 9 ... Piezoelectric substrate 10, 11 ... 1st, 2nd vibrating electrode 10a ... Electrode extension 12 ... Insulating adhesive 26 ... Capacitor element 26a ... Dielectric substrate 26b, 26c ... 1st capacity electrode 26d ... Common electrode 26e ... Recess 36 ... Capacitor element 36a ... dielectric substrates 36b, 36c ... first capacitor electrode 36d ... common electrode 36e ... concave part 36e1 ... bottom part 36e2, 36e2 ... inclined surface part 46 ... capacitor element 46 ... dielectric substrate 46d ... common electrode 46e ... recess 46f ... protruding part

Claims (5)

A substrate provided with a plurality of electrodes on the upper surface;
A capacitor element bonded to the substrate by a conductive adhesive;
A piezoelectric resonant element mounted on the capacitor element using a conductive adhesive,
The capacitor element has a dielectric substrate, a common electrode provided on the lower surface of the dielectric substrate, and a plurality of capacitors provided on the upper surface of the dielectric substrate so as to face the common electrode through the dielectric substrate. An electrode,
The capacitive electrode has an electrode extension that extends from the end face of the dielectric substrate to the lower surface, and the electrode extension of the capacitive electrode and the common electrode are respectively formed on the substrate by the conductive adhesive. Electrically connected to multiple electrodes,
The piezoelectric resonant element includes a piezoelectric substrate and first and second vibrating electrodes that are partially formed on the upper surface and the lower surface of the piezoelectric substrate and are provided to face each other with the piezoelectric substrate interposed therebetween. The portion where the first and second vibrating electrodes are opposed constitutes an energy confining type vibrating portion,
Immediately below the portion where the first and second vibrating electrodes are opposed to each other, on the portion where the conductive adhesive electrically connecting the common electrode of the capacitor element and the electrode of the substrate is disposed said being a dielectric lower surface recess is formed of the substrate are formed so that the front Symbol common electrode extending in the recess, wherein the conductive adhesive remains in the recess, piezoelectric Resonant component. A substrate provided with a plurality of electrodes on the upper surface;
A capacitor element bonded to the substrate by a conductive adhesive;
A piezoelectric resonant element mounted on the capacitor element using a conductive adhesive,
The capacitor element has a dielectric substrate, a common electrode provided on the lower surface of the dielectric substrate, and a plurality of capacitors provided on the upper surface of the dielectric substrate so as to face the common electrode through the dielectric substrate. An electrode,
The capacitive electrode has an electrode extension that extends from the end face of the dielectric substrate to the lower surface, and the electrode extension of the capacitive electrode and the common electrode are respectively formed on the substrate by the conductive adhesive. Electrically connected to multiple electrodes,
The piezoelectric resonant element includes a piezoelectric substrate and first and second vibrating electrodes that are partially formed on the upper surface and the lower surface of the piezoelectric substrate and are provided to face each other with the piezoelectric substrate interposed therebetween. The portion where the first and second vibrating electrodes are opposed constitutes an energy confining type vibrating portion,
A portion where a conductive adhesive that electrically connects the common electrode of the capacitor element and the electrode of the substrate is disposed immediately below the portion where the first and second vibrating electrodes are opposed to each other. A recess is formed on the lower surface of the dielectric substrate,
The recess has a pair of notches extending in the center in the width direction from a pair of opposing side surfaces of the dielectric substrate, and is connected to the remaining lower surface portion of the dielectric substrate between the pair of notches. A flat part is provided,
The piezoelectric resonant component, wherein the common electrode reaches the flat portion, and the conductive adhesive remains in the concave portion .   The piezoelectric resonant component according to claim 1, wherein the concave portion is provided so as to reach the entire width of the lower surface of the dielectric substrate.   The concave portion has a bottom portion and a pair of inclined surface portions connected to the lower surface of the dielectric substrate from both sides of the bottom portion, and the pair of inclined surface portions move away from each other as they reach the lower surface of the dielectric substrate. 2. The piezoelectric resonant component according to claim 1, wherein the common electrode is provided so as to extend from the concave portion to a lower surface portion of the dielectric substrate connected to the concave portion. A case further comprising a case attached to the substrate and having an opening below, wherein the capacitor element and the piezoelectric resonance element are sealed in a sealed space formed by the substrate and the case. Item 5. The piezoelectric resonant component according to any one of Items 1 to 4 .

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