JP5371728B2 - Piezoelectric parts - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric component 1 that prevents sealing property of a space formed around a vibration part of a piezoelectric element 5 from being deteriorated, and secures a wide internal space of a recess near the vibration part of the piezoelectric element 5. <P>SOLUTION: The piezoelectric component 1 includes: the piezoelectric element 5 including a piezoelectric substrate 2 and a first vibration electrode 3 and a second vibration electrode 4 attached to each of both main surfaces of the piezoelectric substrate 2 facing each other across the piezoelectric substrate 2; a support substrate 6 where the piezoelectric element 5 is disposed on one main surface while securing the space for vibration around it; and a case 9 which is provided with a recess 7 for housing the piezoelectric element 5, wherein the entire surface around the opening of the recess 7 is bonded to one main surface of the support substrate 6 by an adhesive sheet 8. The adhesive sheet 8 is attached from the surface around the opening to the inner wall of the recess 7 over the entire periphery around the opening of the recess 7. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a piezoelectric component including a piezoelectric element that vibrates when an electric field is applied.

  As a conventional piezoelectric component, for example, in Patent Document 1, a first piezoelectric substrate in which a first piezoelectric filter unit and a first relay capacitor unit are configured, a second piezoelectric filter unit, and a second relay capacitor unit are disclosed. A second piezoelectric substrate having a structure, an adhesive layer forming a laminate by bonding the first and second piezoelectric substrates, and a plurality of external electrodes applied to the outer surface of the laminate And having a configuration in which the elastic modulus of the adhesive layer is in the range of 0.5 to 3000 MPa, at least one concave portion is formed on the outer peripheral edge of the adhesive layer, and the external electrode material enters the concave portion. ing. And in patent document 1, the adhesive sheet in which the through-hole for not preventing the vibration of the 1st and 2nd piezoelectric filter part was formed as an adhesive layer mentioned above was used, and 1st and 2nd piezoelectric material was used. It is disclosed to have a case substrate that has a cavity for preventing vibration of the filter part, and a surface around the opening of the cavity is bonded to one main surface of the piezoelectric substrate by an adhesive sheet. .

  According to the piezoelectric component disclosed in Patent Document 1, a through hole is formed in the adhesive sheet so as to form a cavity that does not hinder the vibration of the first and second piezoelectric filter portions. A cavity is formed by the hole, and stable characteristics by the first and second piezoelectric filter portions can be obtained.

JP 2002-16478 A Japanese Patent Laid-Open No. 10-308643

  However, in the configuration such as the piezoelectric component disclosed in Patent Document 1, dimensional error when forming the through hole of the adhesive sheet, dimensional error when forming the cavity of the case substrate, and the through hole of the adhesive sheet are Due to errors in adjusting to the cavity of the substrate, the entire surface around the cavity opening of the case substrate may not be bonded to one main surface of the piezoelectric substrate via the adhesive sheet, so the sealing performance of the piezoelectric component is impaired. There was a problem of being.

  Therefore, like the piezoelectric component disclosed in Patent Document 1, the first and second substrates are bonded to each other in an area around the space with an adhesive so as to form a closed space. An electronic component having a structure in which a fillet reaching a side wall of a space in which an adhesive layer is closed has been proposed. In Patent Document 2, the first substrate is a plate-like piezoelectric vibration element, the second substrate has a concave portion, and the concave portion is disposed so as to surround the vibration portion of the piezoelectric vibration element. A piezoelectric component having the above configuration is disclosed.

  According to the piezoelectric component disclosed in Patent Document 2, since the adhesive layer has the fillet reaching the side wall of the closed space, at least the entire surface around the opening of the recess of the second substrate and the first substrate. One main surface is securely bonded by the adhesive layer, and can prevent the sealing performance of the piezoelectric component from being impaired.

  However, in the configuration such as the piezoelectric component disclosed in Patent Document 2, the internal space of the concave portion near the vibrating portion of the first substrate serving as the piezoelectric vibration element cannot be secured sufficiently, and the concave portion of the second substrate is not secured. There is a problem that the fillet on the side wall easily comes into contact with the vibrating portion of the first substrate.

  The present invention has been made in view of the problems in the conventional technology as described above, and an object of the present invention is to prevent the sealing performance of the space formed around the vibrating portion of the piezoelectric element from being impaired. An object of the present invention is to provide a piezoelectric component capable of ensuring a wide internal space of a recess near a vibration part of an element.

  A piezoelectric component of the present invention includes a piezoelectric substrate, a piezoelectric element including a first vibrating electrode and a second vibrating electrode that are attached to both main surfaces of the piezoelectric substrate so as to face each other across the piezoelectric substrate, The piezoelectric element has a support substrate disposed on one main surface while securing a space for vibration around the periphery, and a recess for accommodating the piezoelectric element, and the entire surface around the opening of the recess Is a piezoelectric component comprising a case bonded to one main surface of the support substrate by an adhesive sheet, and the adhesive sheet extends from the peripheral surface of the opening to the concave portion over the entire periphery of the opening of the concave portion. It is characterized in that it is deposited over the inner wall. This is the first piezoelectric component of the present invention.

  The piezoelectric component according to the present invention includes a piezoelectric substrate, a first vibration electrode attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate interposed therebetween, and an inner side of the piezoelectric substrate facing the first vibration electrode. A piezoelectric element including the second vibrating electrode formed, a support substrate in which the piezoelectric element is provided with a space for vibration around and disposed on one main surface, and for storing the piezoelectric element A piezoelectric component having a recess, and a case in which an entire surface around the opening of the recess is bonded to one main surface of the support substrate by an adhesive sheet, and the adhesive sheet includes the recess The entire surface of the periphery of the opening is deposited from the surface around the opening to the inner wall of the recess. This is the second piezoelectric component of the present invention.

  Moreover, the piezoelectric component of the present invention is characterized in that, in each of the above-described configurations, the adhesive sheet is a resin sheet material obtained by impregnating a fiber cloth with a resin.

  The method of manufacturing a piezoelectric component according to the present invention includes a piezoelectric substrate, and a piezoelectric including a first vibrating electrode and a second vibrating electrode that are attached to both main surfaces of the piezoelectric substrate so as to face each other with the piezoelectric substrate interposed therebetween. The element is disposed on one main surface of the support substrate while securing a space for vibration around the case, and the case having a recess for housing the piezoelectric element has at least an opening of the recess. Disposing an adhesive sheet so as to cover the entire surface of the periphery, attaching the adhesive sheet over the entire periphery of the periphery of the opening of the recess from the surface of the periphery of the opening to the inner wall of the recess, the support substrate, and Adhering the entire surface around the opening of the concave portion of the case and one main surface of the support substrate with the adhesive sheet so that the piezoelectric element is accommodated by the concave portion of the case. It is an butterfly. This is the first method for manufacturing a piezoelectric component of the present invention.

  The method for manufacturing a piezoelectric component according to the present invention includes a piezoelectric substrate, first vibration electrodes attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate interposed therebetween, and the first vibration electrode inside the piezoelectric substrate. A step of arranging a piezoelectric element including a second vibrating electrode formed opposite to the substrate on one main surface of a support substrate while securing a space for vibration around the piezoelectric element, and for storing the piezoelectric element A step of disposing an adhesive sheet in a case having a recess so as to cover at least the entire surface around the opening of the recess; and the adhesive sheet from the surface surrounding the opening over the entire periphery of the opening of the recess. A step of depositing on the inner wall of the recess, and the entire surface around the opening of the recess of the case and one main surface of the support substrate so that the piezoelectric element is accommodated by the support substrate and the recess of the case. And before It is characterized in that a step of adhering the adhesive sheet. This is the second method for manufacturing a piezoelectric component of the present invention.

  According to the first piezoelectric component of the present invention, the piezoelectric substrate and the first vibrating electrode and the second vibrating electrode that are attached to both the main surfaces of the piezoelectric substrate so as to face each other with the piezoelectric substrate interposed therebetween are provided. Including a piezoelectric element, a support substrate in which the piezoelectric element secures a space for vibration around and disposed on one main surface, and a recess for accommodating the piezoelectric element, and around the opening of the recess And a case in which the entire surface of the substrate is bonded to one main surface of the support substrate by an adhesive sheet. The adhesive sheet extends from the peripheral surface of the recess to the inner wall of the recess over the entire periphery of the recess opening. Since the entire surface around the opening of the concave portion of the case is adhered to one main surface of the support substrate by the adhesive sheet, the adhesive force between the case and the support substrate is improved. Of the vibration part of the piezoelectric element It is possible to improve the sealing properties of the space formed circumference.

  Further, according to the first piezoelectric component of the present invention, since it is the adhesive sheet that is attached from the surface surrounding the opening to the inner wall of the recess over the entire periphery of the opening of the recess of the case, the thickness thereof Can be made thinner. Accordingly, it becomes possible to secure a wide internal space of the concave portion in the vicinity of the vibration portion of the piezoelectric element, so that the adhesive sheet attached to the inner wall of the concave portion of the case can be made difficult to contact the vibration portion of the piezoelectric element. .

  According to the second piezoelectric component of the present invention, the piezoelectric substrate, the first vibrating electrode attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate interposed therebetween, and the first vibrating electrode inside the piezoelectric substrate are opposed to the first vibrating electrode. A piezoelectric element including the second vibrating electrode, a support substrate in which the piezoelectric element secures a space for vibration around and disposed on one main surface, and a recess for housing the piezoelectric element And a case in which the entire surface around the opening of the recess is bonded to one main surface of the support substrate by an adhesive sheet. Since the entire surface around the periphery of the opening from the surface surrounding the opening to the inner wall of the recess is adhered, the entire surface around the opening of the recess in the case is bonded to one main surface of the support substrate by the adhesive sheet. Improves the adhesion between the substrate and the support substrate Rukoto can, it is possible to improve the sealing properties of the space formed around the vibrating section of the piezoelectric element.

  Further, according to the second piezoelectric component of the present invention, since it is the adhesive sheet that is attached from the surface around the opening to the inner wall of the recess over the entire circumference around the opening of the recess of the case, the thickness thereof Can be made thinner. Accordingly, it becomes possible to secure a wide internal space of the concave portion in the vicinity of the vibration portion of the piezoelectric element, so that the adhesive sheet attached to the inner wall of the concave portion of the case can be made difficult to contact the vibration portion of the piezoelectric element. .

  According to the second piezoelectric component of the present invention, the piezoelectric element includes at least three vibration electrodes (two first vibration electrodes and one second vibration electrode). Compared with the case where the first vibration electrode and the second vibration electrode are each deposited on the main surface, the area where the vibration electrodes face each other can be increased. Therefore, it is possible to obtain the same capacitance with the piezoelectric substrate having the same thickness while reducing the dimension of the piezoelectric element in the width direction. Accordingly, it is possible to reduce the dimension in the width direction of the piezoelectric element while keeping the resonance resistance of the piezoelectric element in inverse proportion to the capacitance value constant. As a result, it becomes possible to secure a wide internal space of the concave portion near the vibrating portion of the piezoelectric element, so that the adhesive sheet attached to the inner wall of the concave portion of the case is less likely to contact the vibrating portion of the piezoelectric element. it can.

  According to the first and second piezoelectric parts of the present invention, when the adhesive sheet is a resin sheet material obtained by impregnating a fiber cloth with resin, the strength of the adhesive sheet is improved by the fiber cloth. Therefore, when the piezoelectric component is exposed to a rapid temperature change, it is possible to prevent the adhesive sheet from being broken by the shear stress generated on the adhesive surface between the case and the support substrate.

  Further, according to the first and second piezoelectric components of the present invention, when the case and the support substrate are bonded by heating, the fiber cloth holds the resin of the adhesive sheet that is heated and melted, The fluidity of the resin can be suppressed. Therefore, it is possible to prevent the resin of the adhesive sheet from flowing and coming into contact with the vibrating portion of the piezoelectric element and degrading the characteristics.

  Further, according to the first and second piezoelectric parts of the present invention, since the fiber cloth having a certain thickness serves as a spacer, the thickness of the cured adhesive sheet on the adhesive surface between the case and the support substrate. Can be prevented from becoming non-uniform.

  According to the first method for manufacturing a piezoelectric component of the present invention, the piezoelectric substrate, the first vibrating electrode and the second vibrating electrode, which are attached to both the main surfaces of the piezoelectric substrate so as to face each other with the piezoelectric substrate interposed therebetween, are provided. A step of arranging a piezoelectric element including a vibration electrode on one main surface of the support substrate while securing a space for vibration around the case, and a case having a concave part for housing the piezoelectric element, at least a concave part Disposing the adhesive sheet so as to cover the entire surface of the periphery of the opening, attaching the adhesive sheet from the surface surrounding the opening to the inner wall of the recess over the entire periphery of the opening of the recess, the support substrate and the case A step of adhering the entire surface of the opening of the recess of the case and one main surface of the support substrate with an adhesive sheet so that the piezoelectric element is accommodated by the recess of the case. Gluing the whole surface Since the adhesive is bonded to one main surface of the support substrate by the cover, the adhesive force between the case and the support substrate can be improved, and the sealing performance of the space formed around the vibrating portion of the piezoelectric element can be improved. Can do.

  Further, according to the first piezoelectric component manufacturing method of the present invention, since it is the adhesive sheet that is attached from the surface around the opening to the inner wall of the recess over the entire circumference around the opening of the recess of the case, The thickness can be reduced. Accordingly, since the internal space of the concave portion near the vibrating portion of the piezoelectric element can be secured widely, it is possible to make it difficult for the adhesive sheet attached to the inner wall of the concave portion of the case to contact the vibrating portion of the piezoelectric element.

  According to the second method for manufacturing a piezoelectric component of the present invention, the piezoelectric substrate, the first vibration electrode attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate sandwiched therebetween, and the first vibration inside the piezoelectric substrate. A step of arranging a piezoelectric element including a second vibration electrode formed opposite to the electrode on one main surface of the support substrate while securing a space for vibration around the electrode, and for storing the piezoelectric element A step of disposing an adhesive sheet on the case having a recess so as to cover at least the entire surface around the opening of the recess, and the inner surface of the recess from the surface surrounding the opening around the entire periphery of the opening of the recess And a step of adhering the entire surface around the opening of the concave portion of the case and one main surface of the supporting substrate with an adhesive sheet so that the piezoelectric element is accommodated by the concave portion of the supporting substrate and the case. From that Since the entire surface around the openings of the recesses is bonded to one main surface of the support substrate with an adhesive sheet, the adhesive force between the case and the support substrate can be improved and formed around the vibration portion of the piezoelectric element. The sealing property of the space to be improved can be improved.

  In addition, according to the second piezoelectric component of the present invention, since the adhesive sheet is applied from the surface around the opening to the inner wall of the recess over the entire periphery of the opening of the recess of the case, the thickness thereof is reduced. can do. Accordingly, it becomes possible to secure a wide internal space of the concave portion in the vicinity of the vibration portion of the piezoelectric element, so that the adhesive sheet attached to the inner wall of the concave portion of the case can be made difficult to contact the vibration portion of the piezoelectric element. .

It is an external appearance perspective view which shows the example of embodiment of the piezoelectric component of this invention. It is sectional drawing in the AA line of an example of embodiment of the piezoelectric component shown in FIG. It is sectional drawing in the AA line of other examples of embodiment of the piezoelectric element in the piezoelectric component shown in FIG. It is sectional drawing in the AA line of the further another example of embodiment of the piezoelectric element in the piezoelectric component shown in FIG. It is sectional drawing in the AA line of the further another example of embodiment of the piezoelectric element in the piezoelectric component shown in FIG. (A) is the external appearance perspective view which looked at the case of the piezoelectric component shown in FIG. 1 from the downward direction, (b) is the external appearance perspective view of the state which removed the case of the piezoelectric component shown in FIG. (A)-(d) is sectional drawing for every process which shows typically an example of embodiment of the manufacturing method of the piezoelectric component of this invention, respectively.

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

  FIG. 1 is an external perspective view showing an example of an embodiment of a piezoelectric component of the present invention. FIG. 2 is a cross-sectional view taken along line AA of the embodiment of the piezoelectric component 1 shown in FIG.

  The piezoelectric component 1 of the example shown in FIGS. 1 and 2 is the first piezoelectric component of the present invention. The piezoelectric substrate 2 and the piezoelectric substrate 2 are opposed to each other with the piezoelectric substrate 2 sandwiched between both main surfaces. A piezoelectric element 5 including the first vibrating electrode 3 and the second vibrating electrode 4 that are attached; a support substrate 6 in which the piezoelectric element 5 is arranged on one main surface while securing a space for vibration around the piezoelectric element 5; A piezoelectric component having a recess 7 for accommodating the piezoelectric element 5 and a case 9 in which the entire surface around the opening of the recess 7 is bonded to one main surface of the support substrate 6 by an adhesive sheet 8. 1 and the adhesive sheet 8 is applied from the surface around the opening to the inner wall of the recess 7 over the entire circumference around the opening of the recess 7.

  With this configuration, the entire surface around the opening of the recess 7 of the case 9 is bonded to one main surface of the support substrate 6 by the adhesive sheet 8, so that the adhesive force between the case 9 and the support substrate 6 is increased. This can improve the sealing performance of the space formed around the vibrating portion of the piezoelectric element 5.

  Moreover, according to the piezoelectric component 1 of the present invention, it is the adhesive sheet 8 that is attached from the surface around the opening to the inner wall of the recess 7 over the entire periphery of the opening of the recess 7 of the case 9. The thickness can be reduced. Accordingly, since it becomes possible to secure a wide internal space of the concave portion 7 near the vibration portion of the piezoelectric element 5, the adhesive sheet 8 attached to the inner wall of the concave portion 7 of the case 9 comes into contact with the vibration portion of the piezoelectric element 5. Can be difficult.

  In FIG. 1, reference numeral 10 indicates an external electrode, reference numerals 11a and 11b in FIG. 2 indicate conductive connection resins, reference numerals 12a and 12b indicate upper surface electrodes, and reference numerals 13a and 13b indicate lower surfaces. The electrode is shown.

The piezoelectric substrate 2, lead zirconate titanate (PZT), lead titanate (PT), sodium-potassium niobate _{(Na 1-x K x NbO} 3), bismuth layered compound _(Example: MBi ₄ Ti _{4 O 15,} M: a piezoelectric ceramic based on a divalent alkaline earth metal element) or a piezoelectric single crystal such as quartz or lithium tantalate.

  From the viewpoint of miniaturization and mountability on a circuit board, the piezoelectric substrate 2 is preferably a rectangular parallelepiped shape having a length of 0.5 to 5 mm, a width of 0.2 to 5 mm, and a thickness of 50 μm to 1 mm.

  Further, the piezoelectric substrate 2 does not necessarily have a uniform thickness over the entire surface. For the purpose of improving the energy confinement of the thickness vibration and improving the resonance characteristics, for example, the first vibration electrode 3 and the second vibration electrode 4 are provided. The thickness of the opposing piezoelectric substrate 2 can be formed thinner or thicker than the surrounding region.

  When the piezoelectric substrate 2 is made of a ceramic material, the raw material powder is pressed by adding a binder, or the raw material powder is mixed with water and a dispersant using a ball mill and then dried, and a binder, a solvent, a plasticizer, etc. are added. Then, it is made into a sheet by a method such as molding by the doctor blade method, and then baked at a peak temperature of 1100 to 1400 ° C. for 0.5 to 8 hours to form a substrate. A piezoelectric substrate 2 having desired piezoelectric characteristics can be obtained by applying a polarization treatment by applying a voltage of 3 to 6 kV / mm.

  In addition, when the piezoelectric substrate 2 is made of a piezoelectric single crystal material, the piezoelectric single crystal material ingot (base material) that becomes the piezoelectric substrate 2 is cut so as to have a predetermined crystal direction, thereby providing desired piezoelectric characteristics. Thus obtained piezoelectric substrate 2 is obtained.

  The first vibrating electrode 3 and the second vibrating electrode 4 are attached to both main surfaces of the piezoelectric substrate 2 so as to face each other with the piezoelectric substrate 2 interposed therebetween. In the following description, it is assumed that the first vibrating electrode 3 and the second vibrating electrode 4 are electrodes having different potentials.

  The first vibrating electrode 3 and the second vibrating electrode 4 are preferably made of a metal film such as gold, silver, copper, or aluminum from the viewpoint of conductivity. The thickness of the electrode 3 is preferably in the range of 0.1 to 5 μm. By making the metal film to be the first vibrating electrode 3 and the second vibrating electrode 4 thicker than 0.1 μm, for example, when exposed to a high temperature in the air, it is possible to suppress a decrease in conductivity due to oxidation. Can do. In addition, by making the metal film thinner than 5 μm, it is possible to prevent the metal film from being peeled off by stress.

  Further, in order to improve the adhesion with the piezoelectric substrate 2, a base electrode layer made of a metal having high adhesion with a ceramic substrate such as chromium is formed in advance on the main surface (surface) of the piezoelectric substrate 2, A desired metal film may be formed thereon to form the first vibration electrode 3 and the second vibration electrode 4.

  A vacuum deposition method, a CVD method, a sputtering method, or the like can be used for depositing the metal film to be the first vibrating electrode 3 and the second vibrating electrode 4.

  The first vibrating electrode 3 and the second vibrating electrode 4 can also be formed by baking a conductive paste containing a metal filler such as silver or copper and using low temperature glass as a binder at a predetermined temperature. . In this case, the thickness of the first vibrating electrode 3 and the second vibrating electrode 4 is preferably in the range of 5 to 30 μm. By making the electrode films to be the first vibrating electrode 3 and the second vibrating electrode 4 thicker than 5 μm, it is possible to suppress an increase in conduction resistance due to poor contact between the metal fillers. Further, by making the thickness thinner than 30 μm, it is possible to prevent the deterioration of the vibration characteristics of the piezoelectric substrate 2 due to the mass effect of the first vibration electrode 3 and the second vibration electrode 4.

  The dimensions of the first vibrating electrode 3 and the second vibrating electrode 4 are, for example, when the piezoelectric substrate 2 has a rectangular parallelepiped shape with a length of 2 mm, a width of 0.5 mm, and a thickness of 0.2 mm. It is assumed that the dimension in the length direction is 1.5 mm, the dimension in the width direction of the piezoelectric substrate 2 is 0.5 mm, and the thickness is 1 μm.

  The piezoelectric element 5 includes a piezoelectric substrate 2 and a first vibrating electrode 3 and a second vibrating electrode 4 that are attached to the surface of the piezoelectric substrate 2 so as to face each other with the piezoelectric substrate 2 interposed therebetween. The vibrating portion of the piezoelectric element 5 indicates a region where the first vibrating electrode 3 and the second vibrating electrode 4 are opposed to each other with the piezoelectric substrate 2 interposed therebetween.

  In the example shown in FIG. 2, the first vibration electrode 3 is on the upper surface, which is the upper main surface, and the second vibration electrode 4 is on the lower surface, which is the lower main surface, of the two main surfaces of the piezoelectric substrate 2. It has a configuration that is attached.

  Here, FIG. 3 is a cross-sectional view taken along line AA of another example of the embodiment of the piezoelectric element 5 in the piezoelectric component 1 shown in FIG.

  As in the example shown in FIG. 3, the piezoelectric element 5 has the first vibration electrode 3 and the second vibration electrode 4 attached to the two main surfaces of the piezoelectric substrate 2 so as to face each other with the piezoelectric substrate 2 interposed therebetween. Then, another first vibrating electrode 3 and second vibrating electrode 4 are opposed to each other inside the piezoelectric substrate 2, and are opposed to the first vibrating electrode 3 and the second vibrating electrode 4 on both main surfaces, respectively. As such, it may be buried. In addition, it is not restricted to the example shown in FIG. 3, The 1st vibration electrode 3 and the 2nd vibration electrode 4 which are embed | buried inside the piezoelectric substrate 2 may be two or more each.

  4 is a cross-sectional view taken along line AA of still another example of the embodiment of the piezoelectric element 5 in the piezoelectric component 1 shown in FIG.

  As illustrated in FIG. 4, the piezoelectric element 5 includes a piezoelectric substrate 2, a first vibration electrode 3 that is attached to both main surfaces of the piezoelectric substrate 2 with the piezoelectric substrate 2 interposed therebetween, and an interior of the piezoelectric substrate 2. The second vibrating electrode 4 formed opposite to the first vibrating electrode 3 may be included. The piezoelectric component 1 of the example shown in FIG. 4 is the second piezoelectric component of the present invention.

  Since the piezoelectric element 5 has such a configuration, the piezoelectric element 5 includes at least three vibration electrodes (two first vibration electrodes 3 and one second vibration electrode 4). Compared with the case where one first vibration electrode 3 and one second vibration electrode 4 are attached to each of the two main surfaces, the area where the vibration electrodes face each other can be increased. Therefore, the capacitance of the same value can be obtained with the piezoelectric substrate 2 having the same thickness while reducing the dimension of the piezoelectric element 5 in the width direction. Therefore, it is possible to reduce the dimension in the width direction of the piezoelectric element 5 while keeping the resonance resistance of the piezoelectric element 5 in an inverse proportion to the capacitance value constant. As a result, it becomes possible to secure a wide internal space of the concave portion 7 near the vibration portion of the piezoelectric element 5, so that the adhesive sheet 8 attached to the inner wall of the concave portion 7 of the case 9 contacts the vibration portion of the piezoelectric element 5. Can be made difficult.

  FIG. 5 is a cross-sectional view taken along line AA of still another example of the embodiment of the piezoelectric element 5 in the piezoelectric component 1 shown in FIG.

  As in the example shown in FIG. 5, the piezoelectric element 5 has the first vibration electrode 3 attached to both main surfaces of the piezoelectric substrate 2 with the piezoelectric substrate 2 sandwiched therebetween, and the first vibration electrode 3 inside the piezoelectric substrate 2. If the second vibration electrode 4 is formed opposite to the first vibration electrode 3, another first vibration electrode 3 and a second vibration electrode 4 are provided inside the piezoelectric substrate 2. Further, it may be embedded so as to face the internal second vibrating electrode 4.

  By adopting such a configuration, the piezoelectric element 5 can ensure a larger facing area between the vibrating electrodes and can increase the capacitance value of the piezoelectric element 5. The dimensions can be further reduced. As a result, it becomes possible to secure a wide internal space of the concave portion 7 near the vibration portion of the piezoelectric element 5, so that the contact of the adhesive sheet 8 attached to the inner wall of the concave portion 7 of the case 9 to the vibration portion of the piezoelectric element 5 is prevented. It can be hard to happen.

  Note that the present invention is not limited to the example shown in FIG. 5, and the number of the first vibration electrodes 3 embedded in the piezoelectric substrate 2 may be two or more, and the number of the second vibration electrodes 4 may be three or more. Is.

  In the example shown in FIG. 2, the piezoelectric element 5 is disposed on one main surface of the support substrate 6 by being supported at both ends by the conductive connection resins 11 a and 11 b, respectively. The conductive connection resins 11a and 11b are disposed on the upper surface of the support substrate 6 via the upper surface electrodes 12a and 12b. Further, both end portions of the upper surface electrodes 12 a and 12 b and the lower surface electrodes 13 a and 13 b in the width direction of the piezoelectric element 5 extend to the peripheral portion of the support substrate 6. And both ends of each electrode 12a, 12b, 13a, 13b are electrically connected to the external electrode 10 in the example shown in FIG. With the electrode configuration as described above, the piezoelectric component 1 of the present invention is electrically connected to an external electronic device or the like via the external electrode 10.

  The support substrate 6 is disposed on one main surface (upper surface) of the piezoelectric element 5 so as to secure a space for vibration around it.

Examples of the material of the support substrate 6 include alumina, barium titanate, lead zirconate titanate (PZT), lead titanate (PT), and sodium / potassium niobate (Na _1-x K _x NbO ₃ )). A ceramic material such as is used. In addition, resin materials such as phenolic resins, polyimide resins, and epoxy resins are also used. In addition, a resin sheet material obtained by impregnating a cloth made of glass fiber or aramid fiber with a resin material such as polyimide resin or epoxy resin is also used.

  In addition, by using the resin material mentioned above as the support substrate 6, it becomes easy to make the thickness into the range of 20-100 micrometers which a crack is comparatively easy to generate | occur | produce with a ceramic material.

  Moreover, the dimension of the support substrate 6 shall be 1.5-7 mm in the length direction, 1-7 mm in the width direction, and 50 micrometers-1 mm in thickness.

  In addition, as a result of arranging the piezoelectric element 5 on the support substrate 6, both ends of the piezoelectric element 5 are supported in order to secure a space for vibration around the piezoelectric element 5, and the vibration portion of the piezoelectric element 5 is supported. It is necessary that the internal space of the nearby recess is sufficiently wide. For example, in the example shown in FIG. 2, both ends of the piezoelectric element 5 are supported by conductive connection resins 11a and 11b, respectively.

  The case 9 has a recess 7 for accommodating the piezoelectric element 5, and the entire surface around the opening of the recess 7 is bonded to one main surface of the support substrate 6 by an adhesive sheet 8.

  The case 9 is made of, for example, a resin material such as a phenol resin, a polyimide resin, or an epoxy resin, or a resin sheet material in which a cloth made of glass fiber, aramid fiber, or the like is impregnated with a polyimide resin or an epoxy resin. It is done.

  In particular, when these resin sheet materials are used, in addition to being able to form the case 9 thinly, it can be excellent in mechanical strength.

  The case 9 can be made of a ceramic material such as alumina or a metal material such as SUS. In the case of using a metal material, the case 9 can also be produced by bending a thin plate to form the recess 7 and processing it into a shape having an adhesive surface.

  When a metal material is used for the case 9, the distance between the conductive connection resins 11a and 11b and the case 9 made of the metal material may be close by reducing the size of the piezoelectric component 1. However, as in the example shown in FIG. 2, the piezoelectric component 1 of the present invention is attached to the adhesive sheet 8 from the surface around the opening to the inner wall of the recess 7 over the entire periphery of the opening of the recess 7. If the adhesive sheet 8 is made of an insulating material such as an epoxy resin, even if the conductive connecting resins 11a and 11b and the case 9 made of a metal material are close to each other, they come into contact with each other to cause an electrical short circuit. While suppressing this, the request for downsizing of the piezoelectric component 1 can be satisfied.

  The case 9 has a length of 1.5 to 7 mm, a width of 1 to 7 mm, and a thickness of 0.2 to 2 mm. The dimensions of the recess 7 of the case 9 are 1.3 to 5 mm in length, 0.8 to 5 mm in width, and 80 μm to 1.5 mm in depth.

  Here, FIG. 6A is an external perspective view of the case 9 of the piezoelectric component 1 shown in FIG. 1 as viewed from below, and FIG. 6B is the case 9 of the piezoelectric component 1 shown in FIG. FIG.

  2 and FIG. 6A, the adhesive sheet 8 adheres the entire surface around the opening of the recess 7 of the case 9 and one main surface of the support substrate 6, and the adhesive sheet 8 Is applied from the surface surrounding the opening to the inner wall of the recess 7 over the entire periphery of the opening of the recess 7.

  With this configuration, the entire surface around the opening of the recess 7 of the case 9 is bonded to one main surface of the support substrate 6 by the adhesive sheet 8, so that the adhesive force between the case 9 and the support substrate 6 is increased. This can improve the sealing performance of the space formed around the vibrating portion of the piezoelectric element 5.

  Moreover, according to the piezoelectric component 1 of the present invention, it is the adhesive sheet 8 that is attached from the surface around the opening to the inner wall of the recess 7 over the entire periphery of the opening of the recess 7 of the case 9. The thickness can be reduced. Accordingly, since it becomes possible to secure a wide internal space of the concave portion 7 near the vibration portion of the piezoelectric element 5, the adhesive sheet 8 attached to the inner wall of the concave portion 7 of the case 9 comes into contact with the vibration portion of the piezoelectric element 5. Can be difficult.

  For the adhesive sheet 8, a resin material such as phenol resin, polyimide resin, or epoxy resin is used. In particular, when the adhesive sheet 8 is a resin sheet material in which a fiber cloth is impregnated with a resin, the strength of the adhesive sheet 8 is improved by the fiber cloth, so that the piezoelectric component 1 is exposed to a rapid temperature change. For example, it is possible to prevent the adhesive sheet 8 from being broken by a shear stress generated on the adhesive surface between the case 9 and the support substrate 6.

  In addition, according to the piezoelectric component 1 of the present invention, when the case 9 and the support substrate 6 are bonded by heating, the resin of the adhesive sheet 8 that is heated and melted is held by the fiber cloth. Fluidity can be suppressed. Therefore, it is possible to prevent the resin of the adhesive sheet 8 from flowing and coming into contact with the vibrating portion of the piezoelectric element 5 to deteriorate the characteristics of the piezoelectric component 1.

  In addition, according to the piezoelectric component 1 of the present invention, since the fiber cloth having a certain thickness serves as a spacer, the thickness of the cured adhesive sheet 8 is inadequate on the adhesive surface between the case 9 and the support substrate 6. It can suppress becoming uniform.

  The thickness of the adhesive sheet 8 is preferably 10 to 80 μm from the viewpoint of ensuring a wide internal space of the concave portion 7 near the vibrating portion of the piezoelectric element 5.

  Next, a method for manufacturing the piezoelectric component 1 of the present invention will be described with reference to FIG. 7A to 7D are cross-sectional views for each process schematically showing an example of the embodiment of the method for manufacturing the piezoelectric component 1 of the present invention.

  First, as shown in FIG. 7A, the piezoelectric substrate 2 and the first vibration electrode 3 and the second vibration that are attached to both main surfaces of the piezoelectric substrate 2 so as to face each other with the piezoelectric substrate 2 interposed therebetween. The piezoelectric element 5 including the electrode 4 is disposed on one main surface of the support substrate 6 while securing a space for vibration in the periphery.

  In this step, for example, the piezoelectric element 5 is mounted on the support substrate 6 using the conductive connection resins 11a and 11b. The conductive connection resins 11a and 11b are obtained by dispersing metal powder in the resin, and the conductive connection resins 11a and 11b are respectively applied onto the two upper surface electrodes 12a and 12b using a dispenser or the like. Then, the piezoelectric element 5 is placed on the conductive connection resin 11a on the upper surface electrode 12a and the second vibration electrode 4 is connected to the conductive connection resin 11b on the upper surface electrode 12b. Alternatively, the resin in the conductive connection resins 11a and 11b is cured by ultraviolet irradiation. At this time, the conductive connection resins 11a and 11b should wrap around from the lower surface side of the piezoelectric substrate 2 to the upper surface side at both ends of the piezoelectric element 5 before the conductive connection resins 11a and 11b are cured. Accordingly, the conductive connection resin 11a can be reliably electrically connected to the first vibration electrode 3, and the conductive connection resin 11b can be reliably electrically connected to the second vibration electrode 4.

  As described above, the piezoelectric element 5 is attached to the main surfaces of the piezoelectric substrate 2 and the piezoelectric substrate 2 with the piezoelectric substrate 2 sandwiched therebetween, as in the example shown in FIGS. 4 and 5. The vibration electrode 3 and the second vibration electrode 4 formed in the piezoelectric substrate 2 so as to face the first vibration electrode 3 may be included.

  On the other hand, as shown in FIG. 7B, an adhesive sheet 8 is disposed in a case 9 having a recess 7 for housing the piezoelectric element 5 so as to cover at least the entire surface around the opening of the recess 7. To do.

  In this step, for example, the adhesive sheet 8 disposed in the case 9 is softened by pressing it with a flat plate heated at a temperature of 80 to 150 ° C. with a stress of 0.05 to 1 MPa, and at the same time, the adhesive sheet 8 is After closely contacting the entire surface around the opening of the recess 7, the heated flat plate is separated from the adhesive sheet 8, the adhesive sheet 8 is cooled to room temperature and solidified, and the periphery of the opening of the recess 7 in the adhesive sheet 8 and the case 9. Is temporarily bonded to the entire surface.

  When the adhesive sheet 8 is softened by heating as described above, the resin material constituting the adhesive sheet 8 has fluidity, so that the adhesive sheet 8 is easily deformed excessively. . Therefore, it is preferable to adjust the fluidity of the adhesive sheet 8 by including about 2 to 50% by mass of a needle-like or spherical filler made of an inorganic material such as silica or plastic in the resin material of the adhesive sheet 8. Thereby, the shape of the adhesive sheet 8 is hardly deformed, and the adhesive sheet 8 and the case 9 can be securely bonded.

  In addition, as a method of heating and pressurizing the adhesive sheet 8, a method of pressing with a heated roller may be adopted in addition to a method of pressing with a heated flat plate.

  In the examples shown in FIGS. 2, 6A and 7B to 7D, the adhesive sheet 8 has no opening, but the adhesive sheet 8 having an opening may be used. Good.

  In addition, when using the adhesive sheet 8 with an opening, it is preferable that the size of the opening of the adhesive sheet 8 be smaller than the size of the opening of the recess 7 of the case 9. With such a configuration, when the adhesive sheet 8 is arranged in the case 9, the opening of the adhesive sheet 8 is a concave portion of the case 9 even if the arrangement position of the adhesive sheet 8 with respect to the case 9 is slightly shifted. 7, the adhesive sheet 8 and the entire surface around the opening of the recess 7 are easily adhered.

  In addition, when using the adhesive sheet 8 without an opening, since it is not necessary to provide an opening in the adhesive sheet 8 in advance, the manufacturing process can be simplified.

  Next, as shown in FIG. 7 (c), the adhesive sheet 8 is adhered from the surface around the opening to the inner wall of the recess 7 over the entire circumference around the opening of the recess 7.

  In addition, the code | symbol 14 in FIG.7 (c) has shown the pin which consists of silicone rubber. 7C shows the shape of the pin 14 in a state where it is elastically deformed in a direction parallel to the bottom surface of the recess 7 by being pressed against the bottom surface of the recess 7.

  In this process, a method of inserting the pin 14 into the internal space of the recess 7 of the case 9 while pressing the adhesive sheet 8 in a portion not bonded to the case 9 with the pin 14 made of silicone rubber is adopted. Good.

  Before carrying out this operation, the case 9 on which the adhesive sheet 8 is placed is placed on a flat plate heated at a temperature of 80 to 150 ° C. with the surface on which the adhesive sheet 8 is not previously placed as the lower surface. It is good to leave. As a result, heat is applied to the adhesive sheet 8 from the heated flat plate through the case 9, and the adhesive sheet 8 is softened and easily deformed.

  The pin 14 made of silicone rubber has a shape along the internal space of the concave portion 7 of the case 9, and the dimension thereof is such that the pin 14 is inserted into the internal space of the concave portion 7 of the case 9. It is preferable that there is a clearance of about 50 μm to 0.2 mm between the inner wall. With such a size, even if the position of the pin 14 is slightly shifted when the pin 14 is inserted into the internal space of the recess 7, the pin 14 is within the opening range of the recess 7. Can be prevented from contacting the surface around the opening of the recess 7 of the case 9, and the case 9 and the pin 14 can be prevented from being damaged.

  Further, as in the example shown in FIG. 7C, the shape of the tip of the pin 14 is preferably a rounded shape with rounded corners. By forming the tip of the pin 14 in such a shape, if the pin 14 is inserted into the internal space of the recess 7, the position of the pin 14 is shifted so that the tip of the pin 14 is around the opening of the recess 7 of the case 9. Even when the surface is slightly in contact with the surface, the tip of the pin 14 and the surface around the opening of the recess 7 of the case 9 can easily slide with each other, and the case 9 and the pin 14 can be prevented from being damaged.

  In addition, since the dimensional error when forming the recess 7 in the case 9 and the error in the positional accuracy of the process when the pin 14 is inserted into the internal space of the recess 7 is about 25 μm to 0.1 mm, as described above, It can be said that the clearance formed between the pin 14 and the inner wall of the recess 7 when inserted into the internal space of the recess 7 of the case 9 is about 50 μm to 0.2 mm.

  Considering the above, the dimension of the tip of the pin 14 is, for example, that the internal space of the recess 7 of the case 9 is a rectangular parallelepiped, and the internal space has a width dimension of the case 9 of 0.9 mm, When the length of the case 9 is 2.8 mm, the cross-sectional shape of the tip of the pin 14 is substantially rectangular, the width of the case 9 is 0.8 mm, and the length of the case 9 is The direction dimension may be 2.7 mm.

  When the pin 14 is inserted into the inner space of the recess 7 while pressing the portion of the adhesive sheet 8 that is not bonded to the case 9 with the pin 14 described above, the adhesive sheet 8 forms the recess 7 of the case 9. The adhesive sheet 8 is attached to the bottom surface of the recess 7 after extending in the depth direction. When the pin 14 is pressed against the bottom surface of the recess 7 via the adhesive sheet 8, the pin 14 made of silicone rubber is elastically deformed in a direction parallel to the bottom surface of the recess 7, and is deformed by the clearance dimension described above. In the example shown in FIG. 7C, the pin 14 has a shape as indicated by a one-dot chain line in FIG. As a result, the side surface of the pin 14 extends the adhesive sheet 8 in a direction parallel to the bottom surface of the recess 7, and the adhesive sheet 8 is adhered to the side wall of the recess 7.

  As described above, the adhesive sheet 8 is deposited from the surface around the opening to the inner wall of the recess 7 over the entire circumference around the opening of the recess 7.

  Moreover, the pressure at the time of pressing the pin 14 on the bottom face of the recessed part 7 via the adhesive sheet 8 is about 0.05-1 MPa, for example. When this level of pressure is applied, the pin 14 is elastically deformed with a dimension of about 0.2 to 0.8 mm in a direction parallel to the bottom surface of the recess 7, so that the pin 14 is inserted into the inner space of the recess 7 of the case 9. It can be said that the clearance formed between the inner wall of the concave portion 7 is about 50 μm to 0.2 mm as described above.

  In the above description, the pin 14 is made of silicone rubber, but may be made of polyimide, polyethylene terephthalate, fluorine resin or the like. In addition, when the pin 14 made of Teflon (registered trademark) is used, although the elastic deformation ratio of the pin 14 is small, the wettability of the adhesive sheet 8 to the pin 14 is poor. When the pin 14 is separated from the adhesive sheet 8 after being pressed, the softened adhesive sheet 8 can be prevented from being welded to the pin 14, which is preferable.

  For the purpose of improving the durability of the pin 14, the pin 14 may be formed by coating a shaft made of a metal such as SUS with these resin materials.

  In addition, it is preferable to apply a primer in advance to the inner wall of the concave portion 7 of the case 9 because adhesion between the adhesive sheet 8 and the inner wall of the concave portion 7 of the case 9 is improved. As this primer, an optimum one depending on the material of the case 9 may be used, such as epoxy resin, polyamide resin, synthetic rubber, urethane, or silicone resin. For example, when the case 9 is made of an epoxy resin, it is desirable to use an epoxy resin primer. In addition, it is preferable to employ | adopt the spray-type application | coating as the application | coating method of the primer to the inner wall of the recessed part 7 of the case 9 from the point that it can apply | coat uniformly to an inner wall and can improve productivity.

  In the above description, the inner wall of the recess 7 is described as indicating the side wall of the recess 7 and the bottom surface of the recess 7. However, the inner wall of the recess 7 may indicate only the side wall of the recess 7. For example, when the portion of the adhesive sheet 8 that is not bonded to the case 9 is pressed by the pins 14, the adhesive sheet 8 is not stretched and is not attached to the bottom surface of the concave portion 7, but only on the side wall of the concave portion 7. Although it may adhere, even in such a case, the effect of the piezoelectric component 1 of the present invention can be exhibited similarly.

  Further, in the above description, the pin 14 is pressed against the bottom surface of the recess 7 so that the adhesive sheet 8 is applied from the surface around the opening to the inner wall of the recess 7 over the entire circumference around the opening of the recess 7. However, a method of attaching the adhesive sheet 8 using air pressure without using the pins 14 may be adopted.

  For example, in the case 9 shown in FIG. 7B, the adhesive sheet 8 having no opening is disposed so as to cover at least the entire surface around the opening of the recess 7, and in a vacuum state in a vacuum chamber or the like, for example, The adhesive sheet 8 disposed in the case 9 is heated to a temperature of 80 to 150 ° C. and pressed with a stress of about 0.05 to 1 MPa, and the entire surface around the opening of the recess 7 of the case 9 and the adhesive sheet 8 are temporarily Adhere.

  Next, while maintaining the state in which the adhesive sheet 8 is softened by heating, the pressure inside the vacuum chamber is returned to atmospheric pressure, whereby the internal space of the recess 7 to which the adhesive sheet 8 is applied and the outside of the recess 7 are maintained. Due to the pressure difference, the adhesive sheet 8 can be applied over the entire circumference around the opening of the recess 7 from the surface around the opening to the inner wall of the recess 7.

  And if the adhesive sheet 8 is cooled and solidified to normal temperature, the adhesive sheet 8 and the whole surface around the opening of the recessed part 7 of the case 9 can be temporarily bonded.

  The adhesive sheet 8 is temporarily bonded by such a process, and then, as shown in FIG. 7 (d), the recess 7 of the case 9 is accommodated so that the piezoelectric element 5 is accommodated by the support substrate 6 and the recess 7 of the case 9. The entire surface around the opening and one main surface of the support substrate 6 are bonded together by an adhesive sheet 8.

  In this step, the adhesive sheet is formed by heating the case 9 disposed on one main surface of the support substrate 6 via the adhesive sheet 8 at a temperature of 120 to 180 ° C. and pressurizing it with a pressure of 0.01 to 3 MPa. By curing the resin constituting 8, the entire surface around the opening of the recess 7 of the case 9 is bonded to one main surface of the support substrate 6.

  Examples of the piezoelectric component of the present invention will be described below. In this example, the piezoelectric component 1 of the example shown in FIG. 2 was produced.

  First, the piezoelectric element 5 having the first vibration electrode 3 and the second vibration electrode 4 facing each other with the piezoelectric substrate 2 sandwiched between the main surface of the piezoelectric substrate 2 is secured around the space for vibration. And arranged on one main surface of the support substrate 6.

  The piezoelectric substrate 2 is obtained by firing a substrate-shaped molded body produced by adding a binder to a powder of lead zirconate titanate and pressing it at a peak temperature of 1200 ° C. for 2 hours to obtain a desired thickness. After forming electrodes for polarization on the upper and lower surfaces of the sintered body to be the piezoelectric substrate 2, a polarization treatment is performed by applying a voltage of 5 kV / mm in the thickness direction at a temperature of 100 ° C. After that, the desired dimensions are obtained. It was prepared by cutting into pieces. The dimensions of the piezoelectric substrate 2 were a rectangular parallelepiped shape having a length of 2.4 mm, a width of 0.5 mm, and a thickness of 0.2 mm.

  Next, the first vibrating electrode 3 and the second vibrating electrode 4 were formed on the main surface of the piezoelectric substrate 2 by vacuum vapor deposition using a mask. The first vibrating electrode 3 and the second vibrating electrode 4 had a thickness of 1 μm and the material was silver. The piezoelectric element 5 was produced through the above steps.

  The first vibration electrode 3 and the second vibration electrode 4 have a length of 1.5 mm in the length direction of the piezoelectric substrate 2, a width direction of the piezoelectric substrate 2 of 0.5 mm, and a thickness of 1 μm. It was supposed to be.

  The support substrate 6 was made of alumina, and the dimensions thereof were 3.2 mm in the length direction, 1.3 mm in the width direction, and 0.3 mm in thickness.

  Further, on the upper surface of the support substrate 6, upper surface electrodes 12 a and 12 b to be electrically connected to the first vibration electrode 3 and the second vibration electrode 4 of the piezoelectric element 5, respectively, are formed on the lower surface of the support substrate 6. Two lower electrodes 13a and 13b used for soldering mounting were provided using a conductive resin material.

  Further, a conductive connection resin in which metal powder is dispersed in a resin is applied to the upper surface electrodes 12a and 12b on the upper surface of the support substrate 6 by a dispenser, and both ends are supported by the conductive connection resin. As described above, the piezoelectric element 5 was disposed on the support substrate 6.

  Next, an adhesive sheet 8 was disposed in a case 9 having a recess 7 for housing the piezoelectric element 5 so as to cover at least the entire surface around the opening of the recess 7.

  The adhesive sheet 8 disposed in the case 9 is softened by pressing it at a pressure of 0.5 MPa with a flat plate heated at a temperature of 130 ° C., and at the same time, is brought into close contact with the entire surface around the opening of the recess 7 of the case 9, By cooling to room temperature, it was solidified and temporarily bonded to the case 9.

  The case 9 is assumed to have a recess 7 for housing the piezoelectric element 5 using an epoxy resin.

  The dimensions of the case 9 were a length of 3.2 mm, a width of 1.3 mm, and a thickness of 0.6 mm. The dimensions of the recess 7 of the case 9 are such that the length is 0.28 mm, the width is 0.9 mm, and the depth is 0.4 mm.

  As the adhesive sheet 8, a resin sheet having a thickness of 40 μm obtained by impregnating a fiber cloth with a resin was used.

  Next, the adhesive sheet 8 was applied from the surface around the opening to the inner wall of the recess 7 over the entire circumference around the opening of the recess 7.

  In this process, while the adhesive sheet 8 disposed in the case 9 is heated to 130 ° C. so that it softens, the portion of the adhesive sheet 8 that is not bonded to the case 9 with the pin 14 made of silicone rubber is attached. The adhesive sheet 8 was adhered to the inner wall of the recess 7 by inserting the pin 14 into the inner space of the recess 7 of the case 9 at 0.5 MPa while pressing.

  The pin 14 made of silicone rubber has a shape along the internal space of the concave portion 7 of the case 9, and the dimension thereof is the inner wall of the concave portion 7 when the pin 14 is inserted into the internal space of the concave portion 7 of the case 9. It was assumed that there was a clearance of 0.1 mm between.

  The pin 14 had a rectangular cross-sectional shape at the tip, the case 9 had a widthwise dimension of 0.7 mm, and the case 9 had a lengthwise dimension of 2.6 mm.

  Thereafter, the entire surface around the opening of the recess 7 of the case 9 and one main surface of the support substrate 6 are bonded by the adhesive sheet 8 so that the piezoelectric element 5 is accommodated by the support substrate 6 and the recess 7 of the case 9. .

  In this bonding, the case 9 disposed on one main surface of the support substrate 6 via the adhesive sheet 8 is heated at a temperature of 150 ° C. and pressurized with a pressure of 2 MPa, whereby the adhesive sheet 8 is The constituent resin was cured, and the entire surface around the opening of the recess 7 of the case 9 was bonded to one main surface of the support substrate 6.

  Then, using the piezoelectric component 1 of the embodiment obtained as described above, a thermal cycle in which holding for 15 minutes in a thermostat controlled at −40 ° C. and + 125 ° C. for 15 minutes is repeated 1000 cycles. An accelerated test was conducted. And it was confirmed whether the sealing performance of the piezoelectric component 1 after the thermal cycle acceleration test was maintained.

  Whether or not the sealing property was maintained was confirmed by a leak test after immersion in a liquid bath maintained at a temperature of 130 ° C. from a room temperature state after the thermal cycle acceleration test.

  As a result, in the piezoelectric component 1 of the example, generation of bubbles in the leak test was not recognized. Therefore, it was found that there was no gap between the entire surface around the opening of the recess 7 of the case 9 and one main surface of the support substrate 6, and the sealing performance was maintained.

  Further, when the piezoelectric component 1 after the thermal cycle acceleration test was cut and the cross section thereof was observed, the adhesive sheet 8 spread from the surface around the opening to the inner wall of the recess 7 over the entire periphery around the opening of the recess 7. It was found that it was uniformly deposited and was not in contact with the vibrating portion of the piezoelectric element 5.

  From these results, the entire surface around the opening of the recess 7 of the case 9 is bonded to one main surface of the support substrate 6 by the adhesive sheet 8, and the adhesive sheet 8 opens over the entire circumference around the opening of the recess 7. By adhering from the peripheral surface to the inner wall of the recess 7, it is possible to prevent the sealing performance of the space formed around the vibration part of the piezoelectric element 5 from being impaired, and in the vicinity of the vibration part of the piezoelectric element 5. It was found that a wide internal space of the recess 7 can be secured.

1: Piezoelectric component 2: Piezoelectric substrate 3: First vibration electrode 4: Second vibration electrode 5: Piezoelectric element 6: Support substrate 7: Recessed portion 8: Adhesive sheet 9: Case
10: External electrode
11a, 11b: Conductive connection resin
12a, 12b: Top electrode
13a, 13b: Bottom electrode
14: Pin

Claims (5)

A piezoelectric element including a piezoelectric substrate and a first vibrating electrode and a second vibrating electrode, which are attached to both main surfaces of the piezoelectric substrate so as to face each other with the piezoelectric substrate interposed therebetween;
A support substrate in which the piezoelectric element is disposed on one main surface while securing a space for vibration around the piezoelectric element;
A piezoelectric component having a recess for housing the piezoelectric element, and a case in which the entire surface around the opening of the recess is bonded to one main surface of the support substrate by an adhesive sheet;
The piezoelectric component, wherein the adhesive sheet is attached from the surface around the opening to the inner wall of the recess over the entire circumference around the opening of the recess. A piezoelectric substrate, a first vibrating electrode attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate sandwiched therebetween, and a second formed inside the piezoelectric substrate so as to face the first vibrating electrode A piezoelectric element including a vibrating electrode;
A support substrate in which the piezoelectric element is disposed on one main surface while securing a space for vibration around the piezoelectric element;
A piezoelectric component having a recess for housing the piezoelectric element, and a case in which the entire surface around the opening of the recess is bonded to one main surface of the support substrate by an adhesive sheet;
The piezoelectric component, wherein the adhesive sheet is attached from the surface around the opening to the inner wall of the recess over the entire circumference around the opening of the recess.   The piezoelectric component according to claim 1, wherein the adhesive sheet is a resin sheet material obtained by impregnating a fiber cloth with a resin. A piezoelectric substrate including a piezoelectric element including a first vibrating electrode and a second vibrating electrode, which are attached to both main surfaces of the piezoelectric substrate so as to face each other with the piezoelectric substrate interposed therebetween, is a space for vibration around the piezoelectric element. Securing and arranging on one main surface of the support substrate;
Arranging an adhesive sheet in a case having a recess for housing the piezoelectric element so as to cover at least the entire surface around the opening of the recess;
Applying the adhesive sheet over the entire periphery of the opening of the recess from the surface around the opening to the inner wall of the recess; and
Bonding the entire surface around the opening of the recess of the case and one main surface of the support substrate with the adhesive sheet so that the piezoelectric element is accommodated by the support substrate and the recess of the case. A method for manufacturing a piezoelectric component, comprising: A piezoelectric substrate, a first vibrating electrode attached to both main surfaces of the piezoelectric substrate with the piezoelectric substrate sandwiched therebetween, and a second formed inside the piezoelectric substrate so as to face the first vibrating electrode A step of arranging a piezoelectric element including a vibration electrode on one main surface of a support substrate while securing a space for vibration around the periphery;
Arranging an adhesive sheet in a case having a recess for housing the piezoelectric element so as to cover at least the entire surface around the opening of the recess;
Applying the adhesive sheet over the entire periphery of the opening of the recess from the surface around the opening to the inner wall of the recess; and
Bonding the entire surface around the opening of the recess of the case and one main surface of the support substrate with the adhesive sheet so that the piezoelectric element is accommodated by the support substrate and the recess of the case. A method for manufacturing a piezoelectric component, comprising:

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