JP2009065522A - Piezoelectric device and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric device that can be small-sized, and to provide a manufacturing method therefor. <P>SOLUTION: A piezoelectric device 100 includes a lower substrate 30; an upper substrate 20 and an intermediate substrate 10 held therebetween, wherein the intermediate substrate includes a piezoelectric vibrating part 11; a frame part 12 surrounding the piezoelectric vibrating part, a connecting part 15 for connecting the piezoelectric vibrating part and the frame part; a first exciting electrode 13 provided on an upper surface of the piezoelectric vibrating part and a second exciting electrode 14 provided on a lower surface of the piezoelectric vibrating part, and the lower substrate includes a first external terminal 32 and a second external terminal 34 provided on its lower surface. The relevant piezoelectric device further includes first wiring lines 23c, 23d, on the lower surface of the upper substrate, extending from the upside of the connecting part to a position, along a side surface, which is most away from the connecting part and passing from the position to the relevant side surface, to electrically connect the first exciting electrode and the first external terminal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a piezoelectric device and a manufacturing method thereof.

  In recent years, with the miniaturization of electronic devices, piezoelectric devices such as crystal resonators are required to be further miniaturized. As a technique for realizing miniaturization of the element, for example, a technique of sealing a quartz substrate having a quartz crystal resonator by sandwiching a quartz substrate having a similar shape from above and below and bonding the three layers of substrates together is proposed. ing.

In addition, by applying such a technique, when a quartz substrate having a plurality of quartz resonators is used, a plurality of small piezoelectric devices can be obtained by cutting the substrate after bonding the substrates from above and below. Thus, the number of steps can be reduced.
JP 2006-94372 A

  An object of the present invention is to provide a piezoelectric device capable of realizing further miniaturization and a manufacturing method thereof.

The piezoelectric device according to the first aspect of the present invention is:
A piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
The intermediate substrate is
A piezoelectric vibration part;
A frame portion surrounding the periphery of the piezoelectric vibrating portion;
A connecting portion for connecting the piezoelectric vibrating portion and the frame portion;
A first excitation electrode provided on the upper surface of the piezoelectric vibrating portion;
A second excitation electrode provided on the lower surface of the piezoelectric vibrating portion;
Have
The lower substrate has a first external terminal and a second external terminal provided on the lower surface thereof,
The piezoelectric device is
On the lower surface of the upper substrate, the first excitation electrode and the first are extended from above the connection portion to a position along the side surface farthest from the connection portion and through the side surface from the position. First wiring for electrically connecting the external terminals of the first wiring;
A second wiring that electrically connects the second excitation electrode and the second external terminal by passing through the side surface of the lower substrate from the lower surface of the connection portion;
Further included.

In the piezoelectric device according to the first aspect,
The upper substrate has a recess provided on the lower surface,
The first wiring may be provided in the recess on the lower surface of the upper substrate.

In the piezoelectric device according to the first aspect,
A first groove continuously provided on one side surface of the intermediate substrate and the lower substrate;
A second groove provided on the other side surface of the lower substrate facing the one side surface;
Have
The first wiring is provided inside the first groove,
The second wiring may be provided inside the second groove.

The piezoelectric device according to the second aspect of the present invention is
A piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
The intermediate substrate is
A plurality of piezoelectric vibrating parts;
A plurality of frame portions surrounding each of the plurality of piezoelectric vibrating portions;
A plurality of connecting portions connecting each of the plurality of piezoelectric vibrating portions and the frame portion;
A plurality of first excitation electrodes provided on an upper surface of each of the plurality of piezoelectric vibrating portions;
A plurality of second excitation electrodes provided on the lower surface of each of the plurality of piezoelectric vibrating portions;
A first through hole provided in the frame portion,
The upper substrate has a first wiring extending on the lower surface thereof from above the connection portion to above the first through hole,
The lower substrate is
A second through hole provided below the first through hole;
A third through hole provided below between the adjacent connecting portions,
The piezoelectric device is
A plurality of dicing lines provided on the frame portion for separating each of the plurality of piezoelectric vibrating portions;
Among the plurality of dicing lines, one dicing line closest to the connection portion passes through the third through hole,
The other dicing lines pass through the first through hole and the second through hole,
The plurality of piezoelectric vibrating portions and the plurality of connecting portions adjacent to each other are provided symmetrically with respect to the one or other dicing lines.

A method for manufacturing a piezoelectric device according to the third aspect of the present invention includes:
A method of manufacturing a piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
A plurality of piezoelectric vibrating portions; a plurality of frame portions surrounding each of the plurality of piezoelectric vibrating portions; a plurality of connecting portions connecting each of the plurality of piezoelectric vibrating portions and the frame portion; and the plurality of piezoelectric vibrations. A plurality of first excitation electrodes provided on an upper surface of each of the parts, a plurality of second excitation electrodes provided on a lower surface of each of the plurality of piezoelectric vibration parts, and a first provided on the frame part. A step of preparing an intermediate substrate having a through hole, an upper substrate having a first wiring on a lower surface, and a lower substrate having a second through hole and a third through hole;
Bonding the lower substrate and the upper substrate and the intermediate substrate so that the first through hole and the second through hole overlap;
The upper substrate, the intermediate substrate, and the lower substrate along one dicing line passing through the third through hole and another dicing line passing through the first through hole and the second through hole Separating the plurality of piezoelectric vibrating parts by cutting
Forming a conductive film in contact with the first wiring in a formation region of the first through hole and the second through hole;
Forming another conductive film in the formation region of the third through hole;
including.

In the piezoelectric device according to the third aspect of the present invention,
The plurality of piezoelectric vibrating portions and the plurality of connecting portions adjacent to each other may be provided symmetrically with respect to the one or other dicing lines.

1. Piezoelectric Device The piezoelectric device 100 according to the present embodiment includes a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them. First, each of the lower substrate, the upper substrate, and the intermediate substrate will be specifically described with reference to FIGS. 1 (A) to 1 (D) and FIG. 1A to 1D are top or bottom views showing an upper substrate, an intermediate substrate, and a lower substrate used in the piezoelectric device according to the present embodiment. FIG. 2 is a cross-sectional view showing the piezoelectric device according to the present embodiment, and is a view corresponding to the II-II cut plane in FIGS. 1 (A) to 1 (D).

1.1. Upper Substrate FIG. 1A is a bottom view schematically showing the upper substrate 20. The upper substrate 20 has a concave portion 21 and a frame portion 22 provided around the concave portion 21.

  The material of the upper substrate 20 is not particularly limited as long as it is an insulating material, but considering the difference in thermal expansion of the material, it is preferably the same material as the intermediate substrate, and can be made of, for example, quartz.

  The recess 21 is formed at least in a region including the edge 24 of the upper substrate 20. The edge 24 is preferably located along a side surface farthest from the connecting portion 15 of the intermediate substrate 10 described later, and more preferably provided at the center of the side surface. The recess 21 is provided so as to communicate with the side surface. The recess 21 is formed in a region including the upper part of the connection part 15 of the intermediate substrate 10.

  In the present embodiment, the shape of the lower surface of the upper substrate 20 is such that the frame portion 22 is provided in a region along the side surface of the upper substrate 20 other than the edge portion 24, and the recess 21 is provided in the inner region and the edge portion 24. Provided. Moreover, it is preferable that the depth of the recessed part 21 is more than the thickness of the 1st wiring 23c. Further, when a recess is formed in the frame portion of the intermediate substrate and the wiring is arranged at a position corresponding to the recess, the upper substrate may be a flat plate.

  The upper substrate 20 further has a first wiring 23 c provided inside the recess 21. The first wiring 23c is drawn from the upper part of the connection part described later to the edge part 24. The material of the first wiring c is not particularly limited as long as it is a conductive material. For example, the first wiring c may have a multilayer structure in which a Cr film is used as a base and an Au film is formed thereon.

1.2. Intermediate Substrate FIG. 1B is a top view schematically showing the intermediate substrate 10, and FIG. 1C is a bottom view schematically showing the intermediate substrate 10.

  The intermediate substrate 10 includes a piezoelectric vibration part 11, a frame part 12 surrounding the piezoelectric vibration part 11, a connection part 15 connecting the piezoelectric vibration part 11 and the frame part 12, and a vibration part for vibrating the piezoelectric vibration part 11. A first excitation electrode 13 and a second excitation electrode 14 are included.

  The intermediate substrate 10 has, for example, a C-shaped slit 16 so that a region other than the connection portion 15 does not contact. In the intermediate substrate 10, a region inside the slit 16 can function as the piezoelectric vibrating portion 11, and a region outside the slit 16 can function as the frame portion 12 for joining to the upper substrate 20 and the lower substrate 30.

  The intermediate substrate 10 has a step structure. Specifically, as shown in FIG. 2, the region of the frame portion 12 is the thickest, the region of the piezoelectric vibrating portion 11 is the thinnest, and the connection portion 15 is inclined on the upper and lower surfaces from the piezoelectric vibrating portion 11 to the frame portion 12. And gradually getting thicker. The piezoelectric vibration part 11 is located at the center in the thickness direction of the frame part 12. By having such a shape, a cavity is formed between the upper substrate 20 and the lower substrate 30, and the vibration of the piezoelectric vibrating portion 11 is possible.

  The piezoelectric vibrating part 11 is made of a piezoelectric material such as quartz, lithium tantalate, or lithium niobate. The piezoelectric vibrating portion 11, the connecting portion 15, and the frame portion 12 are preferably made of a quartz substrate, and are an AT-cut quartz substrate manufactured by rotating and cutting around the X axis with the substrate surface parallel to the X axis. be able to. The piezoelectric vibrating portion 11 is connected to the frame portion 12 via the connecting portion 15, and the connecting portion 15 is provided in the vicinity of one of the side surfaces facing the longitudinal direction of the intermediate substrate 10.

  The first excitation electrode 13 is provided on the upper surface of the intermediate substrate 10 so as to be in contact with the piezoelectric vibrating portion 11, and the second excitation electrode 14 is provided on the lower surface of the intermediate substrate 10 so as to be in contact with the piezoelectric vibrating portion 11. It has been. Each of the first excitation electrode 13 and the second excitation electrode 14 is drawn from the first wiring 23 a and the second wiring 33 a provided on the connection portion 15 and extends onto the piezoelectric vibration portion 11. Yes. As a material of the first excitation electrode 13 and the second excitation electrode 14, for example, a Cr film may be used as a base, and a multilayer structure having an Au film thereon may be used.

  The intermediate substrate 10 further includes a first groove portion 25. The first groove portion 25 is provided in a region overlapping with the edge portion 24 of the upper substrate 20. The first groove portion 25 can be, for example, a semicircle or an arc shape in a plan view, and penetrates from the upper surface to the lower surface of the intermediate substrate 10.

1.3. Lower Substrate FIG. 1D is a bottom view schematically showing the lower substrate 30. The lower substrate 30 has a first external terminal 32 and a second external terminal 34 provided on the lower surface thereof.

  The material of the lower substrate 30 is not particularly limited as long as the upper substrate 20 is an insulating material, but is preferably the same material as the intermediate substrate, and can be made of, for example, quartz.

  The first external terminal 32 and the second external terminal 34 are used to electrically connect the piezoelectric device 100 to an external device. The first external terminal 32 and the second external terminal 34 are provided at positions separated from each other, and specifically, provided at the end portions of the lower substrate 20 that face each other in the longitudinal direction. As a material of the first external terminal 32 and the second external terminal 34, for example, a Cr film may be used as a base, and a multilayer structure having an Au film thereon may be used.

  The lower substrate 30 further includes a first groove part 35 and a second groove part 36. The first groove 35 is provided in a region overlapping the edge 24 of the upper substrate 20 and surrounded by the first external terminals 32. Similar to the first groove 25 described above, the first groove 35 can be semicircular or arcuate in plan view, and penetrates from the upper surface to the lower surface of the lower substrate 30. The second groove portion 36 is provided in a region surrounded by the second external terminals 34 and on the side surface closest to the connection portion 15 of the intermediate substrate 10. Similarly, the second groove portion 36 can be semicircular or arcuate in plan view and penetrates from the upper surface to the lower surface of the lower substrate 30.

1.4. Overall Structure A wiring structure provided in the piezoelectric device 100 so that the first excitation electrode 13 and the second excitation electrode 14 are electrically connected to the first external terminal 32 and the second external terminal 34, respectively. Will be described in detail.

  FIG. 2 is a cross-sectional view of the piezoelectric device according to the present embodiment. The first excitation electrode 13 is electrically connected to the first external terminal 32 via the first wirings 23a, b, c, d. The first excitation electrode 13 and the first wiring 23 a are integrally formed on the intermediate substrate 10. The first wiring 23a is connected to the first wiring 23c using the first wiring 23b. The first wiring 23c is connected to the first external terminal 32 by the first wiring 23d.

  The first wiring 23d is continuously provided in the edge portion 24 of the upper substrate 20 and the first groove portions 25 and 35 provided on the side surfaces of the intermediate substrate 10 and the lower substrate 30, and the first external terminal 32.

  The second excitation electrode 14 is electrically connected to the second external terminal 34 via the second wirings 33a and 33b. The second excitation electrode 14 and the second wiring 33 a are integrally formed on the lower surface of the intermediate substrate 10, and are drawn out to reach the end surface of the intermediate substrate 10. The second wiring 33a is connected to the second external terminal 34 via the second wiring 33b. The second wiring 33 b is continuously provided in the second groove portion 36 provided on the side surface of the lower substrate 30 and is connected to the second external terminal 34.

  The first wiring 23b is formed of, for example, a bump made of solder, gold or the like, a conductive adhesive, or the like. The first wiring 23d and the second wiring 33b are formed of a conductive material such as a bump made of solder or gold.

  Next, the bonding positions of the upper substrate 20 and the intermediate substrate 10 and between the intermediate substrate 10 and the lower substrate 30 will be described.

  At the bonding surface between the upper substrate 20 and the intermediate substrate 10, the frame portion 22 of the upper substrate 20 overlaps with the frame portion 12 of the intermediate substrate 10, and the edge portion 24 of the upper substrate 20 extends to the first groove 25 of the intermediate substrate 10. The end of the upper substrate 20 opposite to the edge 24 of the first wiring 23c overlaps the end of the intermediate substrate 10 opposite to the first wiring 23a opposite to the first excitation electrode 13 side. is doing.

  At the joint surface between the intermediate substrate 10 and the lower substrate 30, the first groove portion 25 of the intermediate substrate 10 and the first groove portion 35 of the lower substrate overlap, and the first wiring 23a of the intermediate substrate 10 The second groove 36 in the lower substrate 30 overlaps at the end opposite to the one excitation electrode 13 side.

  In the piezoelectric device 100 according to the present embodiment, the first wiring 23c for electrically connecting the first excitation electrode 13 and the first external terminal 32 is drawn from the lower surface of the upper substrate 20 to the outer surface. ing. Thereby, for example, the through hole is provided in the frame portion of the intermediate substrate, and the piezoelectric device 100 can be easily downsized as compared with the case where the first wiring is drawn out to the outer surface of the frame portion through the through hole. The area of the piezoelectric vibration part can be increased, and consequently the CI (Crystal Impedance) value can be kept low.

2. Next, a method for manufacturing the piezoelectric device 100 according to the present embodiment will be described. 3-6 is a figure which shows the manufacturing method of the piezoelectric device 100 which concerns on this Embodiment.

  First, an upper crystal plate 220 (upper substrate), an intermediate crystal plate 210 (intermediate substrate), and a lower crystal plate 230 (lower substrate) are prepared (see FIG. 3). Upper crystal plate 220, intermediate crystal plate 210, and lower crystal plate 230 are substrates on which a plurality of upper substrate 20, intermediate substrate 10, and lower substrate 30 are arranged, respectively.

  FIG. 4 is a bottom view showing the intermediate crystal plate 210 according to the present embodiment. The intermediate crystal plate 210 has a dicing line L1 and a dicing line L2 at the boundary of the intermediate substrate 10. The dicing line L1 and the dicing line L2 are provided so as to cross at a right angle. The dicing lines L1 extend in the column direction and are arranged in the row direction. The dicing lines L2 extend in the row direction and are arranged in the column direction. In the intermediate crystal plate 210, the plurality of intermediate substrates 10 are reversed and arranged every other row. Therefore, a plurality of adjacent intermediate substrates 10 are provided symmetrically with respect to the dicing line L1. In addition, the intermediate crystal plate 210 has a first through hole 225 provided on the dicing line L1. The first through-hole 225 becomes the above-described first groove portion 25 when the intermediate crystal plate 210 is later cut along the dicing line L1.

  As described above, the intermediate crystal plate 210 has the step structure, the C-shaped slit 16, and the first through hole 225, which are provided by etching using, for example, a photolithography technique. The first excitation electrode 13 and the second excitation electrode 14 can be obtained, for example, by applying an etching, vapor deposition method or sputtering method using a photolithography technique.

  Similarly to the intermediate crystal plate 210, the upper crystal plate 220 and the lower crystal plate 230 also have a dicing line L1 and a dicing line L2. Further, the plurality of upper substrates 20 and the plurality of lower substrates 30 are arranged in an inverted manner every other column, and are provided symmetrically with respect to the dicing line L1.

  In the upper crystal plate 220, as shown in FIG. 3, two first wirings 23c provided in adjacent upper crystal plates 220 are provided continuously and symmetrically. The concave portion 21 of the upper crystal plate 220 is provided by etching or sandblasting using a photolithography technique. The first wiring 23c can be obtained by applying, for example, a vapor deposition method or a sputtering method.

  The lower crystal plate 230 has a second through hole 235 and a third through hole 236 on the dicing line L1. The second through hole 235 and the third through hole 236 are provided by etching using a photolithography technique. The second through holes 235 and the third through holes 236 are provided on the alternating dicing lines L1. When the lower crystal plate 230 is later cut along the dicing line L1, the second through hole 235 becomes the above-described first groove portion 35, and the third through hole 236 becomes the above-described second groove portion 36. It becomes. The first external terminal 32 and the second external terminal 34 can be obtained by applying a vapor deposition method or a sputtering method.

  Next, the upper crystal plate 220 and the lower crystal plate 230 are joined to the intermediate crystal plate 210 (see FIG. 5). It is preferable to apply direct bonding for bonding. By directly joining the quartz plates, the generation of stress due to heating can be reduced and the frequency can be stabilized.

  The alignment at the time of joining is performed such that the first through hole 225 and the second through hole 235 overlap with each other, and the third through hole 236 is positioned below the connection portion 15. Further, when bonding, a first wiring 23 b is formed by sandwiching a conductive film such as a bump made of solder, gold or the like, or a conductive adhesive between the upper crystal plate 220 and the intermediate crystal plate 210. The first wiring 23 b is provided on the connection portion 15 of the intermediate crystal plate 210, and is arranged so as to overlap with the first wiring 23 c of the upper crystal plate 220.

  Through the above steps, as shown in FIG. 5, a piezoelectric quartz crystal device 300 (piezoelectric device) having a plurality of quartz crystal plates and having a plurality of piezoelectric vibrating portions can be obtained.

  Next, the piezoelectric quartz crystal device 300 is cut and divided along the dicing lines L1 and L2 (see FIG. 6). FIG. 6 is a view showing a cross section of the chip after cutting, and corresponds to FIG.

  Next, a first wiring 23 d and a second wiring 33 b are formed by embedding a conductive material in the first groove portions 25 and 35 and the second groove portion 36.

  Through the above steps, the piezoelectric device 100 can be obtained (see FIG. 2).

  According to the method for manufacturing the piezoelectric device 100 according to the present embodiment, since the piezoelectric quartz crystal device 300 has a symmetrical shape with respect to the dicing line L1, the first through hole 225, the second through hole 235, the first The members on the dicing line L1 such as the three through holes 236 can be formed at the same time, and the number of processes can be reduced.

  Note that the first wiring 23d and the second wiring 33b are made of conductive material in the first through hole 225, the second through hole 235, and the third through hole 236 before the piezoelectric quartz crystal device 300 is cut and divided. You may form by embedding. Thereby, since the wiring of two adjacent piezoelectric devices can be formed in a single process, the number of processes can be reduced.

3. Modified Example A piezoelectric device according to a modified example of the present embodiment is different from the piezoelectric device 100 in which the connecting part is provided at one place in that the connecting part is provided at two places.

  FIG. 7A to FIG. 7D are views showing the upper substrate 120 and the intermediate substrate 110 that constitute the piezoelectric device according to the modification of the present embodiment, and FIG. 1A to FIG. Corresponds to (D). In addition, since the material of the structure used for the piezoelectric device concerning a modification is the same as the material of the structure corresponding to the piezoelectric device 100 mentioned above, description is abbreviate | omitted.

3.1. Upper Substrate FIG. 7A is a diagram showing the lower surface of the upper substrate 120. The upper substrate 120 has a recess 121 and a first wiring 123c on the lower surface.

  The recess 121 is formed at least in a region including the edge 124 of the upper substrate 120. The edge portion 124 is preferably located along a side surface farthest from connecting portions 115a and 115b of the intermediate substrate 110, which will be described later, and more preferably provided at a position closest to the connecting portion 115a on the side surface. The recess 121 is provided so as to communicate with the side surface having the edge 124. The recess 121 is formed in a region including the upper side of one connection portion 115a of the intermediate substrate 110.

  In the present embodiment, the shape of the lower surface of the upper substrate 120 is such that the frame portion 122 is provided in a region along the side surface of the upper substrate 120 other than the edge portion 124, and the recess 121 is formed in the inner region and the edge portion 124. Provided. The depth of the recess 121 is preferably equal to or greater than the thickness of the first wiring 123c.

  The upper substrate 120 further includes a first wiring 123 c provided inside the recess 121. The first wiring 123c is drawn from the upper part of the connection part described later to the edge part 124.

3.2. Intermediate Substrate FIG. 7B is a top view schematically showing the intermediate substrate 110, and FIG. 7C is a bottom view schematically showing the intermediate substrate 110.

  The intermediate substrate 110 includes a piezoelectric vibrating portion 111, a frame portion 112 surrounding the piezoelectric vibrating portion 111, two connection portions 115a and 115b connecting the piezoelectric vibrating portion 111 and the frame portion 112, and the piezoelectric vibrating portion 111. It has the 1st excitation electrode 113 and the 2nd excitation electrode 114 for making it oscillate.

  The intermediate substrate 110 has, for example, a C-shaped first slit 116 and a rectangular second slit 117 so that regions other than the connection portions 115a and 115b do not come into contact with each other. The second slit 117 is provided between the connecting portions 115a and 115b. In the intermediate substrate 110, a region surrounded by the first slit 116 and the second slit 117 functions as the piezoelectric vibration unit 111, and regions outside the slit 116 and the second slit 117 are the upper substrate 120 and the lower substrate. It can function as the frame part 112 for joining.

  The intermediate substrate 110 has a step structure. Specifically, the region of the frame part 112 is the thickest, the region of the piezoelectric vibration part 111 is the thinnest, and the connection parts 115a and 115b are inclined gradually from the piezoelectric vibration part 111 to the frame part 112 and gradually thicken. ing. The piezoelectric vibrating portion 111 is located at the center in the thickness direction of the frame portion 112.

  The piezoelectric vibration part 111 is connected to the frame part 112 via connection parts 115a and 115b, and the connection parts 115a and 115b are provided in the vicinity of one of the side surfaces facing the longitudinal direction of the intermediate substrate 110.

  The first excitation electrode 113 is provided on the upper surface of the intermediate substrate 110 so as to be in contact with the piezoelectric vibrating portion 111, and the second excitation electrode 114 is provided on the lower surface of the intermediate substrate 110 so as to be in contact with the piezoelectric vibrating portion 111. It has been. Each of the first excitation electrode 113 and the second excitation electrode 114 is drawn from the first wiring 123a and the second wiring 133a provided on the connection portion 115b and extends onto the piezoelectric vibration portion 111. Yes.

  The intermediate substrate 110 further includes a first groove portion 125. The first groove 125 is provided in a region overlapping with the edge 124 of the upper substrate 120. The first groove portion 125 can be, for example, a semicircle or an arc shape in plan view, and penetrates from the upper surface to the lower surface of the intermediate substrate 110.

3.3. Lower Substrate FIG. 7D is a bottom view schematically showing the lower substrate 130. The lower substrate 130 has a first external terminal 132 and a second external terminal 134 provided on the lower surface thereof.

  The first external terminal 132 and the second external terminal 134 are used to electrically connect the piezoelectric device to an external device. The first external terminal 132 and the second external terminal 134 are provided at positions separated from each other, and specifically, provided at the end portions of the lower substrate 120 facing each other in the longitudinal direction.

  The lower substrate 130 further includes a first groove part 135 and a second groove part 136. The first groove 135 overlaps with the edge 124 of the upper substrate 120 and is provided in a region surrounded by the first external terminals 132. Similar to the first groove 125 described above, the first groove 135 can be semicircular or arcuate in plan view, and penetrates from the upper surface to the lower surface of the lower substrate 130. The second groove 136 is provided in a region surrounded by the second external terminals 134 and below the side of the connecting portion 115 a on the side surface closest to the connecting portions 115 a and 115 b of the intermediate substrate 10. Similarly, the second groove 136 can be semicircular or arcuate in plan view, and penetrates from the upper surface to the lower surface of the lower substrate 130.

3.4. Overall Structure The first excitation electrode 113 is electrically connected to the first external terminal via the first wiring 123a, b, c, d. The first wiring 123 d is continuously provided in the edge portion 124 of the upper substrate 120 and the first groove portion 125 provided in the side surfaces of the intermediate substrate 110 and the lower substrate 130, and is connected to the first external terminal 132. Connecting.

  The second excitation electrode 114 is electrically connected to the second external terminal 134 through the second wirings 133a and 133b. The second excitation electrode 114 and the second wiring 133 a are integrally formed on the lower surface of the intermediate substrate 110, and are drawn out to reach the end surface of the intermediate substrate 110. The second wiring 133a is connected to the second external terminal 134 via the second wiring 133b. The second wiring 133 b is continuously provided in the second groove 136 provided on the side surface of the lower substrate 130 and is connected to the second external terminal 134.

  Since the piezoelectric device according to the modified example has the connecting portions 115a and 115b at two locations, the piezoelectric vibrating portion 111 can be supported more firmly and the strength of the piezoelectric device can be increased.

  In the piezoelectric device according to the modified example, the first wiring 123c for electrically connecting the first excitation electrode 113 and the first external terminal 132 is provided from the lower surface of the upper substrate 120 opposite to the connection portions 115a and 115b. Pulls out to the outer side. This makes it possible to easily reduce the size of the piezoelectric device and to increase the area of the piezoelectric vibrating portion as compared with, for example, pulling out from the frame portion of the intermediate substrate to the outer surface on the opposite side of the connecting portion, and thus CI. The value can be kept low.

  Further, according to the piezoelectric device according to the modification, the first wiring 123c is provided inside, so that the frequency of disconnection is reduced as compared with the case where the wiring is routed from the outer surface on the connection portion side to the outer surface on the opposite side. be able to.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, a tuning fork type vibrator may be used as the piezoelectric vibration portion. The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same purposes and results). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

FIG. 1A is a bottom view showing an upper substrate constituting the piezoelectric device according to the present embodiment, and FIG. 1B is an upper view showing an intermediate substrate constituting the piezoelectric device according to the present embodiment. FIG. 1C is a bottom view showing an intermediate substrate constituting the piezoelectric device according to the present embodiment, and FIG. 1D is a bottom view constituting the piezoelectric device according to the present embodiment. It is a bottom view which shows a side board | substrate. FIG. 2 is a cross-sectional view showing the piezoelectric device according to the present embodiment. FIG. 3 is a diagram for explaining a method of manufacturing a piezoelectric device according to the present embodiment. FIG. 4 is a diagram for explaining a method of manufacturing a piezoelectric device according to the present embodiment. FIG. 5 is a diagram for explaining a method of manufacturing a piezoelectric device according to the present embodiment. FIG. 6 is a diagram for explaining a method of manufacturing a piezoelectric device according to the present embodiment. FIG. 7A is a bottom view showing an upper substrate constituting a piezoelectric device according to a modification, and FIG. 7B is a top view showing an intermediate substrate constituting the piezoelectric device according to the modification. FIG. 7C is a bottom view showing an intermediate substrate constituting a piezoelectric device according to a modification, and FIG. 7D is a bottom view showing a lower substrate constituting the piezoelectric device according to the modification. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Intermediate substrate, 11 ... Piezoelectric vibration part, 12 ... Frame part, 13 ... 1st excitation electrode, 14 ... 2nd excitation electrode, 15 ... Connection part, 16 ... Slit, 20 ... Upper substrate, 21 ... Recessed part, 22 ... Frame portion, 23a, 23b, 23c, 23d, ... first wiring, 24 ... Edge portion, 25 ... First groove portion, 30 ... Lower substrate, 32 ... First external terminal, 33a, 33b ... First 2 ... 34 ... 2nd external terminal, 35 ... 1st groove part, 36 ... 2nd groove part, 100 ... Piezoelectric device, 110 ... Intermediate substrate, 111 ... Piezoelectric vibration part, 112 ... Frame part, 113 ... 1st 1 excitation electrode, 114 ... second excitation electrode, 115a, 115b ... connecting portion, 120 ... upper substrate, 121 ... recess, 122 ... frame portion, 123a, 123b, 123c, 123d, ... first wiring, 124 ... Edge, 1 DESCRIPTION OF SYMBOLS 5 ... 1st groove part, 130 ... Lower board | substrate, 132 ... 1st external terminal, 133a, 133b ... 2nd wiring, 134 ... 2nd external terminal, 135 ... 1st groove part, 136 ... 2nd Groove, 210 ... Intermediate crystal plate, 220 ... Upper crystal plate, 225 ... First through hole, 230 ... Lower crystal plate, 235 ... Second through hole, 236 ... Third through hole, 300 ... Piezoelectric crystal device

Claims (6)

A piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
The intermediate substrate is
A piezoelectric vibration part;
A frame portion surrounding the periphery of the piezoelectric vibrating portion;
A connecting portion for connecting the piezoelectric vibrating portion and the frame portion;
A first excitation electrode provided on the upper surface of the piezoelectric vibrating portion;
A second excitation electrode provided on the lower surface of the piezoelectric vibrating portion;
Have
The lower substrate has a first external terminal and a second external terminal provided on the lower surface thereof,
The piezoelectric device is
On the lower surface of the upper substrate, the first excitation electrode and the first are extended from above the connection portion to a position along the side surface farthest from the connection portion and through the side surface from the position. First wiring for electrically connecting the external terminals of the first wiring;
A second wiring that electrically connects the second excitation electrode and the second external terminal by passing through the side surface of the lower substrate from the lower surface of the connection portion;
A piezoelectric device further comprising: In claim 1,
The upper substrate has a recess provided on the lower surface,
The first wiring is a piezoelectric device provided in the recess on the lower surface of the upper substrate. In claim 1 or 2,
A first groove continuously provided on one side surface of the intermediate substrate and the lower substrate;
A second groove provided on the other side surface of the lower substrate facing the one side surface;
Have
The first wiring is provided inside the first groove,
The second wiring is a piezoelectric device provided inside the second groove. A piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
The intermediate substrate is
A plurality of piezoelectric vibrating parts;
A plurality of frame portions surrounding each of the plurality of piezoelectric vibrating portions;
A plurality of connecting portions connecting each of the plurality of piezoelectric vibrating portions and the frame portion;
A plurality of first excitation electrodes provided on an upper surface of each of the plurality of piezoelectric vibrating portions;
A plurality of second excitation electrodes provided on the lower surface of each of the plurality of piezoelectric vibrating portions;
A first through hole provided in the frame portion,
The upper substrate has a first wiring extending on the lower surface thereof from above the connection portion to above the first through hole,
The lower substrate is
A second through hole provided below the first through hole;
A third through hole provided below between the adjacent connecting portions,
The piezoelectric device is
A plurality of dicing lines provided on the frame portion for separating each of the plurality of piezoelectric vibrating portions;
Among the plurality of dicing lines, one dicing line closest to the connection portion passes through the third through hole,
The other dicing lines pass through the first through hole and the second through hole,
The plurality of piezoelectric vibrating portions and the plurality of connecting portions adjacent to each other are provided symmetrically with respect to the one or another dicing line. A method of manufacturing a piezoelectric device including a lower substrate and an upper substrate, and an intermediate substrate sandwiched between them,
A plurality of piezoelectric vibrating portions; a plurality of frame portions surrounding each of the plurality of piezoelectric vibrating portions; a plurality of connecting portions connecting each of the plurality of piezoelectric vibrating portions and the frame portion; and the plurality of piezoelectric vibrations. A plurality of first excitation electrodes provided on an upper surface of each of the parts, a plurality of second excitation electrodes provided on a lower surface of each of the plurality of piezoelectric vibration parts, and a first provided on the frame part. A step of preparing an intermediate substrate having a through hole, an upper substrate having a first wiring on a lower surface, and a lower substrate having a second through hole and a third through hole;
Bonding the lower substrate and the upper substrate and the intermediate substrate so that the first through hole and the second through hole overlap;
The upper substrate, the intermediate substrate, and the lower substrate along one dicing line passing through the third through hole and another dicing line passing through the first through hole and the second through hole Separating the plurality of piezoelectric vibrating parts by cutting
Forming a conductive film in contact with the first wiring in a formation region of the first through hole and the second through hole;
Forming another conductive film in the formation region of the third through hole;
A method for manufacturing a piezoelectric device, comprising: In claim 5,
The plurality of piezoelectric vibrating portions and the plurality of connecting portions adjacent to each other are provided symmetrically with respect to the one or another dicing line.