Piezoelectric component

A piezoelectric component which suppress ripples in the range of oscillation frequency and achieves stabilization of oscillation frequency is provided. A piezoelectric component of the invention includes a support substrate; a piezoelectric element having an elongated shape, comprising excitation electrodes disposed on one principal surface and the other principal surface thereof, respectively, the excitation electrodes facing each other; a first support portion and a second support portion which are disposed between both ends in a longitudinal direction of the piezoelectric element and the support substrate; and an electrically conductive joining material which joins the first support portion and the second support portion to the ends of the piezoelectric element, respectively. A center of the piezoelectric element is offset with respect to an intermediate point between the first support portion and the second support portion as seen in a plan view of the piezoelectric component.

TECHNICAL FIELD

The present invention relates to a piezoelectric component which is suitably used as a resonator, for example.

BACKGROUND ART

A piezoelectric component which serves as a resonator comprises a support substrate, a piezoelectric element, a pair of support portions for the installation of the piezoelectric element, an electrically conductive joining material, and a lid body. The piezoelectric element has vibrating electrodes formed on opposite principal surfaces thereof, respectively, so as to have mutually opposed regions (intersecting regions). The piezoelectric element is installed, with its one and the other ends arranged in symmetrical relation on their respective paired support portions disposed on the support substrate. That is, the center of the piezoelectric component coincides with an intermediate point between the first support portion and the second support portion as seen in a plan view.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In the resonator, harmonic components (higher-order vibration) of longitudinal vibration mode, transverse vibration mode, or planar-extensional vibration mode occur as so-called ripples in the range of oscillation frequency. Increasingly greater ripples may lead to lack of stability in oscillation frequency.

The invention has been devised in view of the circumstances as discussed above, and accordingly an object of the invention is to provide a piezoelectric component which achieves suppression of ripples in the range of oscillation frequency and is thus conducive to stabilization of oscillation frequency.

Solution to Problem

The invention provides a piezoelectric component comprising: a support substrate; a piezoelectric element having an elongated shape, comprising excitation electrodes disposed on one principal surface and the other principal surface thereof, respectively, the excitation electrodes facing each other; a first support portion and a second support portion which are disposed between both ends in a longitudinal direction of the piezoelectric element and the support substrate; and an electrically conductive joining material which joins the first support portion and the second support portion to the ends of the piezoelectric element, respectively, a center of the piezoelectric element being offset with respect to an intermediate point between the first support portion and the second support portion as seen in a plan view of the piezoelectric component.

Advantageous Effects of Invention

According to the invention, since the center of the piezoelectric element is offset from the intermediate point between the first support portion and the second support portion, it follows that the degree of symmetry in the vibrating electrode-bearing region which is not secured by the electrically conductive joining material is lowered. This makes it possible to shift ripple frequency within the range of oscillation frequency to go out of the oscillation frequency range, or reduce ripples within the oscillation frequency range.

DESCRIPTION OF EMBODIMENTS

A piezoelectric component in accordance with a present embodiment will be particularized with reference to drawings.

FIG. 1(a)is a schematic plan view, with parts (lid body) omitted, showing a piezoelectric component according to this embodiment, and,FIG. 1(b)is a schematic sectional view showing the piezoelectric component taken along the line A-A shown inFIG. 1(a).

The piezoelectric component as exemplified inFIG. 1comprises: a support substrate1; an elongated piezoelectric element2comprising vibrating electrodes21disposed on one principal surface and the other principal surface thereof, respectively, the vibrating electrodes facing each other; a first support portion31and a second support portion32which are disposed on the support substrate1, and are connected to the other principal surface (lower surface, in this embodiment) of the piezoelectric element2so as to support both ends in a longitudinal direction of the piezoelectric element2; and an electrically conductive joining material4which joins the first support portion31and the second support portion32to the other principal surface at the ends of the piezoelectric element2, respectively, wherein, a center C2of the piezoelectric element2is offset with respect to an intermediate point C1between the first support portion31and the second support portion32as seen in a plan view of the piezoelectric component.

For example, the support substrate1comprises a dielectric body11shaped in a rectangular flat plate which is 2.5 mm to 7.5 mm in length, 1.0 mm to 3.0 mm in width, and 0.1 mm to 1 mm in thickness. As the dielectric body11, it is possible to use a ceramic material such as alumina or barium titanate and a resin material such as a glass epoxy resin.

One principal surface (upper surface, in this embodiment) of the dielectric body11constituting the support substrate1is provided with a first capacitive electrode121and a second capacitive electrode122. The first capacitive electrode121and the second capacitive electrode122are electrically connected to the vibrating electrodes21of the piezoelectric element2, respectively, and serve to form capacitance between each of them and a grounding electrode123which will hereafter be described. The first capacitive electrode121is disposed so as to extend from one end of the support substrate1in the longitudinal direction toward the center thereof, whereas the second capacitive electrode122is disposed so as to extend from the other end of the support substrate1in the longitudinal direction toward the center thereof.

The other principal surface (lower surface, in this embodiment) of the support substrate1is provided with the grounding electrode123opposed so as to straddle the first capacitive electrode121and the second capacitive electrode122through the dielectric body11, and an input-output electrode124for input and output of signals.

Moreover, the support substrate1has, at a side surface thereof, a side electrode125which extends from one principal surface to the other principal surface, and electrically connects the first capacitive electrode121or the second capacitive electrode122to the input-output electrode124.

As in this embodiment, when the first capacitive electrode121and the second capacitive electrode122are opposed to the grounding electrode123through the dielectric body11, by setting the area of opposed regions of the first capacitive electrode121and the grounding electrode123to equal the area of opposed regions of the second capacitive electrode122and the grounding electrode123, the capacitance obtained in each of the former opposed regions and the latter opposed regions is identical. Moreover, when the first capacitive electrode121and the second capacitive electrode122are opposed to the grounding electrode123through the dielectric body11, it is possible to increase the area of opposed regions of the first capacitive electrode121and the grounding electrode123and the area of opposed regions of the second capacitive electrode122and the grounding electrode123, and thereby obtain greater capacitance. Note that the capacitance obtained in the opposed regions of each electrode pair is determined in accordance with the characteristics of an amplifier circuit element which constitutes an oscillation circuit in conjunction with the piezoelectric component connected to the amplifier circuit element.

In the drawings, the side electrode125is also disposed on a part of the side surface of the support substrate1which is electrically connected to the grounding electrode123for purposes of convenience of soldering to an external circuit board.

As the material constituting the first capacitive electrode121, the second capacitive electrode122, the grounding electrode123, and the side electrode125, for example, it is possible to use an electrically conductive resin prepared by dispersing powder of metal such for example as gold, silver, copper, aluminum, or tungsten in a resin (electrically conductive paste) and a thick-film conductor obtained by baking of the metal powder with an additive such as glass added. The material in use may be formed with a plating such as a Ni/Au plating or a Ni/Sn plating on an as needed basis.

On the support substrate1, there are arranged the first support portion31and the second support portion32, and, the piezoelectric element2is mounted thereon so as to be able to vibrate. More specifically, with the first support portion31and the second support portion32connected to the other principal surface of the piezoelectric element2, the piezoelectric element2is installed so as to be able to vibrate while being supported at its longitudinal ends on the first and second support portions31and32. For example, the first support portion31and the second support portion32are each an electrically conductive columnar member made of a resin containing powder of metal such for example as gold, silver, copper, aluminum, or tungsten in a dispersed state. For example, each support portion is shaped in a rectangular prism or a circular cylinder which is 0.1 mm to 1.0 mm in longitudinal and transverse lengths (in diameter) and 10 μm to 100 μm in thickness.

Moreover, inFIG. 1, the electrically conductive joining material4is disposed on each of the first support portion31and the second support portion32to join each of the first support portion31and the second support portion32to at least the other principal surface at each end of the piezoelectric element2. Since the first support portion31and the second support portion32are each made of an electrically conductive material, it follows that electrical conduction is established between the vibrating electrode21of the piezoelectric element2and each of the first support portion31and the second support portion32. For example, solder or an electrically conductive adhesive is used as such an electrically conductive joining material4. Exemplary of the solder is a lead-free material made of copper, tin, and silver, and, exemplary of the electrically conductive adhesive is an epoxy conductive resin or a silicone resin containing conductive particles of silver, copper, nickel, or the like in an amount of 75 to 95% by mass.

The piezoelectric element2is an elongated member comprising a piezoelectric body22and vibrating electrodes21disposed on opposite principal surfaces (one and the other principal surfaces) of the piezoelectric body22, respectively, the vibrating electrodes facing each other. The piezoelectric body22constituting the piezoelectric element2may be shaped in a flat plate which is 1.0 mm to 4.0 mm in length, 0.2 mm to 2 mm in width, and 40 μm to 1 mm in thickness. The piezoelectric body22may be made of piezoelectric ceramics formed of, for example, lead titanate, lead zirconate titanate, lithium tantalate, lithium niobate, sodium niobate, potassium niobate, or a bismuth lamellar compound used as a base material.

Moreover, the piezoelectric element2has the vibrating electrodes21arranged on one and the other principal surfaces of the piezoelectric body22, respectively, so as to have mutually opposed regions (intersecting regions). The vibrating electrode21disposed on one principal surface (upper surface) of the piezoelectric body22is formed so as to extend from one longitudinal end of the piezoelectric body22toward the other longitudinal end thereof, whereas the vibrating electrode21disposed on the other principal surface (lower surface) of the piezoelectric body22is formed so as to extend from the other longitudinal end toward the one longitudinal end, thus forming the mutually opposed regions. Each of the vibrating electrodes21, which can be made of metal such for example as gold, silver, copper, or aluminum, is laminated in a thickness of 0.1 μm to 3 μm on the principal surface of the piezoelectric body22. As shown in the drawings, an end electrode23is disposed on each end face of the piezoelectric element2. The vibrating electrode21of the piezoelectric element2is electrically connected to the first capacitive electrode121via the end electrode23, the electrically conductive joining material4, and the first support portion31, and, the other vibrating electrode21of the piezoelectric element2is electrically connected to the second capacitive electrode122via the electrically conductive joining material4and the second support portion32.

In such a piezoelectric element2, upon application of a voltage between the vibrating electrodes21, piezoelectric vibration such as thickness longitudinal vibration or thickness sliding vibration occurs in the opposed regions (intersecting regions) of the vibrating electrodes21at a specific frequency.

As shown inFIG. 1(b), a lid body5may be placed on the support substrate1to cover the piezoelectric element2. The lid body5is joined to the edge of the upper surface of the support substrate1by an adhesive or other means, thus providing the capability of protecting the piezoelectric element2, which is housed in an internal space defined by the lid body5together with the support substrate1, against external physical and chemical influences, and a hermetic sealing function to prevent intrusion of foreign matters such as water into the space defined by the lid body5together with the support substrate1. As the material constituting the lid body5, for example, it is possible to use metal such as stainless steel, ceramics such as alumina, a resin, and glass. It is also possible to use a material made of an insulating resin such as an epoxy resin containing inorganic fillers in an amount of 25 to 80% by mass in the interest of reduction of difference in thermal expansion coefficient between the lid body5and the support substrate1.

The center C2of the piezoelectric element2is offset with respect to the intermediate point C1between the first support portion31and the second support portion32as seen in a plan view. As employed herein, the term “intermediate point C1between the first support portion31and the second support portion32” refers to a bisection point in which a line segment connecting the barycenter of the first support portion31and the barycenter of the second support portion32as seen in a plan view is bisected. Moreover, the center C2of the piezoelectric element2means the barycenter of the piezoelectric element2as seen in a plan view. In reality, the position of the intermediate point C1between the first support portion31and the second support portion32cannot be visually checked in a plan view in a condition where the piezoelectric element2is mounted thereon. Therefore, the offset positional relationship can be examined only when the piezoelectric element2is removed or represented in perspective, but, for the sake of convenience, it is assumed herein that there is an offset in a plan view.

In the case where the position of the center C2of the piezoelectric element2is offset from the intermediate point C1between the first support portion31and the second support portion32, the degree of symmetry in the vibrating electrode21-bearing region which is not secured by the electrically conductive joining material4, namely, the vibrating region, is lowered. This makes it possible to shift ripple frequency within the range of oscillation frequency to go out of the oscillation frequency range, or reduce ripples within the oscillation frequency range.

At this time, a principal mode of vibration contributing to oscillation (for example, thickness sliding vibration) corresponds to vibration which occurs only in the intersecting regions of the vibrating electrodes21formed on the piezoelectric element2, that is; a so-called energy-trapping vibration mode. Even if the ends of the piezoelectric element2are misaligned with respect to each other, the misalignment exerts no influence so long as the vibrating electrodes21defining the intersecting regions are maintained free from damage. Thus, a piezoelectric component characterized by stable oscillation frequency can be provided.

For example, in the piezoelectric element2which is 2.4 mm in longitudinal dimension, 0.5 mm in widthwise dimension, and 0.2 mm in thickness, it is assumed that ripples exist at 8.05 MHz. In this case, when the center C2of the piezoelectric element2coincides with the intermediate point C1between the first support portion31and the second support portion32, there is a ripple phase difference of 15°. In this regard, it has been confirmed that the ripple phase difference can be reduced to 0.7° by displacing the center C2of the piezoelectric element2from the intermediate point C1by an amount of 0.2 mm in the longitudinal direction. That is, the displacement enables ripple suppression and reduction of the magnitude of the ripples.

It is noted that the center C2of the piezoelectric element2may be displaced with respect to the intermediate point C1between the first support portion31and the second support portion32in either a direction longitudinally of the piezoelectric element2or a transverse direction perpendicular to the longitudinal direction, or in both of these directions. InFIG. 1, there is shown a case where the center C2of the piezoelectric element2is offset with respect to the intermediate point C1both in the longitudinal direction and the transverse direction of the piezoelectric element2.

For example, when higher-order vibration ascribable to longitudinal vibration (lengthwise vibration) appears as ripples in the range of frequencies of thickness sliding vibration (oscillation frequency range), it is advisable that the center C2of the piezoelectric element2is offset with respect to the intermediate point C1between the first support portion31and the second support portion32in the longitudinal direction of the piezoelectric element2(X direction in the drawing). Suitable adjustment of longitudinal displacement makes it possible to suppress ripples resulting from longitudinal vibration.

Moreover, when higher-order vibration ascribable to transverse vibration (widthwise vibration) appears as ripples in the range of frequencies of thickness sliding vibration (oscillation frequency range), it is advisable that the center C2of the piezoelectric element2is offset with respect to the intermediate point C1between the first support portion31and the second support portion32in the transverse direction perpendicular to the longitudinal direction of the piezoelectric element2(Y direction in the drawing). Suitable adjustment of transverse displacement makes it possible to suppress ripples resulting from transverse vibration.

In addition, when ripples occur due to higher-order vibration ascribable to both of longitudinal vibration and transverse vibration, it is advisable that the center C2of the piezoelectric element2is offset with respect to the intermediate point C1between the first support portion31and the second support portion32both in the longitudinal direction and the transverse direction of the piezoelectric element2. Suitable adjustment of displacement in both of the longitudinal direction and the transverse direction makes it possible to suppress ripples resulting from each of longitudinal vibration and transverse vibration. At this time, as further adjustment, as shown inFIG. 1, the piezoelectric element2may be turned, and be displaced in at least one of the longitudinal direction and the transverse direction.

It is advisable that the distance of displacement of the piezoelectric element2in the X direction is equal to 0.8% to 15% of the longitudinal dimension of the piezoelectric element2, and that the distance of displacement of the piezoelectric element2in the Y direction is equal to 4 to 30% of the transverse dimension of the piezoelectric element2.

Such a distance is suitably determined with consideration given to the dimensions of the piezoelectric element2involving a shift of ripples or suppression of ripples, as well as to the positions of the first support portion31and the second support portion32involving the installation of the piezoelectric element2.

Moreover, when the piezoelectric element2is not only simply displaced in the longitudinal and/or transverse direction but is also turned as shown in the drawing, expressed differently, when the longitudinal direction of the piezoelectric element2is inclined with respect to a line segment connecting the first support portion31and the second support portion32, a part of the piezoelectric element2which is secured at the first support portion31and a part of the piezoelectric element2which is secured at the second support portion32differ from each other in widthwise dimension and in lengthwise dimension, thus throwing various vibration modes, including the transverse vibration mode, the longitudinal vibration mode, and the planar-extensional vibration mode off balance at a time. That is, the fundamental vibrations of the different vibration modes can be divided and damped at a time, and higher-order vibrations corresponding to these modes can thus be divided and damped at a time, with consequent suppression of ripples in the oscillation frequency range.

Moreover, as shown inFIG. 2, it is preferable that at least part of the side surface (end face) at each end of the piezoelectric element2is covered with the electrically conductive joining material4. In other words, it is preferable that the electrically conductive joining material4which joins the piezoelectric element2and the support substrate1together is fixedly attached to the other principal surface and the side surface at each end of the piezoelectric element2. In this case, the end of the piezoelectric element2can be secured firmly, wherefore harmonic vibration ascribable to longitudinal or transverse vibration, in particular, can be damped, with consequent further suppression of ripples in the oscillation frequency range.

Moreover, as shown inFIG. 3, it is preferable that at least part of one principal surface at each end of the piezoelectric element2is covered with the electrically conductive joining material4. In other words, it is preferable that the electrically conductive joining material4which joins the piezoelectric element2and the support substrate1together is fixedly attached to the other principal surface, the side surface (end face), and one principal surface at each end of the piezoelectric element2. When the electrically conductive joining material4is further extended fixedly to the one principal surface of the piezoelectric element2, the end of the piezoelectric element2can be secured more firmly, wherefore harmonic vibration ascribable to longitudinal or transverse vibration, in particular, can be damped, with consequent further suppression of ripples in the oscillation frequency range.

Moreover, as shown inFIG. 4, it is preferable that the first support portion31and the second support portion32are each composed of at least two or more bumps. In other words, it is preferable that the first support portion31and the second support portion32are each divided into two or more pieces. In the case where the first support portion31and the second support portion32are each composed of at least two or more bumps, the intermediate point C1between the first support portion31and the second support portion32refers to a bisection point in which is bisected a line segment connecting the barycenter of a plurality of first support portions31and the barycenter of a plurality of second support portions32as seen in a plan view.

To begin with, the support substrate1is fixed in place, and the position of the center C2of the piezoelectric element2is determined. Then, the piezoelectric element2is removed to uncover the end faces or sections of the plurality of first and second support portions31and32, and, the barycenter of the first support portions31and the barycenter of the second support portions32are determined by graphic analyses, for example.

The barycenter of the plurality of first support portions31is determined on the basis of a line connecting the barycentric points of the individual first support portions31. For example, when two first support portions31are provided, the barycenter of the first support portions31corresponds to a bisection point in which a line segment connecting the barycentric points of the individual first support portions31is bisected.

Moreover, when more than two first support portions31are provided, for example, an X-Y plane including a group of barycentric points of the individual first support portions31is assumed. Then, a given point in the X-Y plane is defined as an origin point, and, mutually perpendicular coordinate axes passing through the origin point are defined as the X axis and the Y axis, respectively. Given that the barycentric point of each of the first support portions31is represented by the Xi and Yi position coordinates, the total sum of the X and Y coordinate values at all the points is divided by the number of the points. On the basis of the value obtained by the above division, the barycenter of the plurality of first support portions31can be determined. For example, when there are five points, the barycenter of a group of the points (Xg and Yg coordinates) can be expressed in equation form as: Xg=(X1+X2+X3+X4+X5)/5; and Yg=(Y1+Y2+Y3+Y4+Y5)/5. This method holds true for the determination of the barycenter of the plurality of second support portions32.

Moreover, the position of the intermediate point C1corresponding to a bisection point in which a line segment connecting the barycenter of the plurality of first support portions31and the barycenter of the plurality of second support portions32is bisected, and the position of the center C2of the piezoelectric element2are determined. From this a judgment can be made as to whether the foregoing falls within the scope of the invention.

FIG. 4represents, partially in a transparent manner, the first support portion31and the second support portion32indicated by broken lines. In the case shown inFIG. 4, the electrically conductive joining material4is disposed so as to fill a gap between the first support portions31, as well as a gap between the second support portions32, and also fill a gap between the piezoelectric element2and the first capacitive electrode121or the second capacitive electrode122. Since the division of each of the first support portion31and the second support portion32into two or more pieces and the displacement of the piezoelectric element2help lower the degree of symmetry in the fixed locations of the piezoelectric element2even further, it is possible to achieve further departure of harmonics of ripple-causing vibration mode from the oscillation frequency range.

For example, when the first support portion31and the second support portion32are each cylindrically shaped, it is advisable that 2 to 5 cylindrical members, each having a diameter equal to 20 to 40% of the width of the piezoelectric element2, are spaced 100 to 300 μm apart for example, as the first support portions31or the second support portions32. These support portions are advisably arranged so that the piezoelectric element2stays horizontal when installed. When two members are provided as the first support portions31or the second support portions32, as shown inFIG. 4, the support portions are advisably arranged side by side in the transverse direction of the piezoelectric element2. Moreover, when five members are provided as the first support portions31or the second support portions32, as shown inFIG. 5, it is advisable that four of them are arranged so as to define the vertices of a square as seen in a plan view, and the remaining one is placed at the center of the square defined by the vertices from the standpoint of increasing the number of points of contact with the piezoelectric element2for stable installation of the piezoelectric element2in parallel with the support substrate1. Also in this case, a principal mode of vibration corresponds to the so-called energy-trapping vibration mode, wherefore the construction is not subjected to the influence of component misalignment.

It should be understood that the application of the invention is not limited to the embodiments described heretofore, and that various changes and modifications are possible without departing from the scope of the invention.

The following describes a method of manufacturing the piezoelectric component in the present embodiment.

First, a segmentable substrate for the production of the support substrate1. For example, powder of raw materials such as lead titanate, lead zirconate titanate, and barium titanate is mixed together with water and a dispersant in a ball mill, and, after the addition of a binder, a plasticizer, and so forth, the mixture is subjected to drying process and particle sizing process. The material thereby obtained is press-molded, and, the molded body is subjected to perforating process on an as needed basis, is degreased at a predetermined temperature, is fired at peak temperatures ranging from 900° C. to 1600° C., and is ground in a predetermined thickness. After that, for example, by printing an electrically conductive paste containing powder of metal such as silver or nickel and glass, performing firing at a predetermined temperature, and forming the first capacitive electrode121, the second capacitive electrode122, and so forth, the support substrate1is obtained.

On the support substrate1thus obtained, support portions are formed in a thickness of about 1 μm to 100 μm from an electrically conductive paste by means of screen printing or otherwise. More specifically, on the first capacitive electrode121, for example, there is provided the first support portion31in the form of a bump formed by solidifying a resin containing dispersed metal powder, and, on the second capacitive electrode122, for example, there is provided the second support portion32in the form of a bump formed by solidifying a resin containing dispersed metal powder.

Next, to obtain piezoelectric porcelain (piezoelectric body22) constituting the piezoelectric element2, for example, powder of raw materials is mixed together with water and a dispersant in a ball mill, and, after the addition of a binder, a plasticizer, and so forth, the mixture is subjected to drying process and particle sizing process. The material thereby obtained is press-molded and is then fired, forming the piezoelectric porcelain. An electrode is formed on the end face of the piezoelectric porcelain thus obtained, and, for example, a voltage of 0.4 kV/mm to 6 kV/mm is applied endways at a temperature of, for example, 25° C. to 300° C. to effect polarization.

The vibrating electrode21formed on each of the upper and lower surfaces of the piezoelectric body22is obtained by laminating a metallic film on each of the upper and lower surfaces of the piezoelectric body22thus obtained by means of vacuum deposition, PVD, sputtering, or otherwise, forming an about 1 to 10 μm-thick photoresist film on each metallic film by means of screen printing or otherwise, and performing patterning by photoetching. The piezoelectric element2is produced by cutting the patterned piezoelectric body22in a predetermined size by means of dicing or otherwise.

Then, the piezoelectric element2is fixedly mounted on the first support portion31and the second support portion32of the support substrate1via the electrically conductive joining material4. When an electrically conductive adhesive made of a resin containing dispersed metal powder is used as the electrically conductive joining material4, after applying the electrically conductive adhesive onto the first support portion31and the second support portion32by a dispenser or other means, the piezoelectric element2is placed on the first support portion31and the second support portion32. Then, the resin constituting the electrically conductive adhesive is cured by application of heat or under ultraviolet irradiation.

To render the center C2of the piezoelectric element2offset with respect to the intermediate point C1between the first support portion31and the second support portion32as seen in a plan view, proper adjustment is made to the arrangement of the piezoelectric element2during its installation on the first support portion31and the second support portion32. Moreover, by making proper adjustment to the amount of the electrically conductive joining material4or by applying the electrically conductive joining material4so that the electrically conductive joining material4extends to the side surface or upper surface of the piezoelectric element2, it is possible to cover at least part of the side surface at each end of the piezoelectric element2with the electrically conductive joining material4or cover at least part of the upper surface at each end of the piezoelectric element2with the electrically conductive joining material4. Furthermore, to obtain the first support portion31and the second support portion32which are each composed of at least two or more bumps, a plurality of bumps are provided as individual support portions.

Then, an opening periphery of the lid body5is joined to the edge of the upper surface of the support substrate1so as to cover the piezoelectric element2. A segmentable lid cluster sheet having a plurality of recesses is used to form the lid body5. The lid cluster sheet is placed on the segmentable substrate, with the recess positioned so as to cover the piezoelectric element2, and, the projection of the lid cluster sheet, which constitutes the opening periphery of the lid body5, is joined to the edge of the upper surface of the support substrate1. For example, a thermosetting insulating adhesive is applied to the projection of the prepared lid cluster sheet constituting the opening periphery of the lid body5, and, the lid body5is placed on the upper surface of the support substrate1. After that, the lid body5or the support substrate1is subjected to heat to raise the temperature of the insulating adhesive to 100 to 150° C., thus curing the insulating adhesive, whereby the lid body5is joined to the upper surface of the support substrate1.

Lastly, the assemblage is cut along the boundary between the individual piezoelectric components (component pieces) by means of dicing or otherwise.

The piezoelectric component in the present embodiment is produced in accordance with the method thus far described. This method enables production of the piezoelectric component that achieves suppression of ripples in the range of oscillation frequency and is thus conducive to stabilization of oscillation frequency with high productivity.

REFERENCE SIGNS LIST