JP2015186196A - Piezoelectric vibrating piece and piezoelectric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration piece with a suppressed influence on vibration caused by support stress and to provide a piezoelectric device including the piezoelectric vibration piece.SOLUTION: A piezoelectric vibration piece 130 is provides with a pair of main surfaces in a rectangular shape with long sides L2 and short sides L1, the piezoelectric vibration piece 130 including: a vibration part 131 in which a pair of excitation electrodes 134 are formed on the respective pair of main surfaces for causing a vibration in a prescribed frequency; a support part 132 provided with a first surface away from the vibration part extending parallel to the long side or the short side and parallel to the main surface and a second surface opposing the first surface; and a connection part 133 extending perpendicular to the long side or the short side so as to connect an end part of the long side or the short side to the one end of the support part. Also, in the piezoelectric vibration pieces, extraction electrodes 135 are respectively extracted from the pair of excitation electrodes to the second surface of the support part.

Description

  The present invention relates to a piezoelectric vibrating piece in which an influence on vibration due to a support stress is suppressed, and a piezoelectric device having the piezoelectric vibrating piece.

  A piezoelectric device on which a piezoelectric vibrating piece having a vibrating part that vibrates at a predetermined frequency has high electrical accuracy and high stability, and has various electrical characteristics such as little secular change. Is widely used as a reference frequency source for consumer equipment.

  In such a piezoelectric device, frequency temperature characteristics, crystal impedance (CI), frequency reproducibility, aging, and the like may be deteriorated due to stress generated when the piezoelectric vibrating piece is fixed. For example, Patent Document 1 discloses that an L-shaped support portion is formed in the vibration portion and the piezoelectric vibration piece is supported by the support portion to prevent stress from being transmitted to the vibration portion. ing.

JP 2012-74807 A

  However, in Patent Document 1, since the support portion is formed in an L shape, the size of the vibrating portion must be reduced when the piezoelectric vibrating piece is placed in a limited space in the piezoelectric device. A reduction in the size of the vibration part leads to an increase in equivalent resistance and a decrease in the resonance Q value, which causes a problem that the piezoelectric vibrating piece is difficult to oscillate. In addition, it is difficult to increase the size of the piezoelectric device because it is against the trend of miniaturization of the piezoelectric device. Further, in Patent Document 1, the piezoelectric vibrating piece is supported at both ends of the L-shaped support part, and a connection part is formed at the center of the support part to connect the support part and the vibration part. Since it occurs between both ends, the support stress is transmitted to the vibration part via the connecting part, and may affect the vibration.

  An object of the present invention is to provide a piezoelectric vibrating piece that has no influence on vibration due to support stress, and a piezoelectric device having the piezoelectric vibrating piece.

  A piezoelectric vibrating piece according to a first aspect includes a vibrating portion having a pair of rectangular main surfaces having a long side and a short side, and a pair of excitation electrodes formed on the pair of main surfaces to vibrate at a predetermined frequency. A supporting portion having a first surface extending in parallel with the long side or the short side and being parallel to the main surface and a second surface opposite to the first surface, and one end of the supporting portion and the long side or the short side. A connecting portion extending perpendicularly to the long side or the short side so as to connect the end portions of the sides. Further, the piezoelectric vibrating piece has an extraction electrode drawn from each excitation electrode to the second surface of the support portion.

  In the piezoelectric resonator element according to the second aspect, in the first aspect, the length of the support portion is equal to or longer than the length of the long side or the short side that extends in parallel with the support portion being separated, and the support portion is separated. It is below the length of the long side or the short side extending in parallel.

  In the piezoelectric resonator element according to the third aspect, in the first aspect and the second aspect, the vibration unit includes an excitation region where the excitation electrode is formed and a peripheral region surrounding the excitation region. The excitation region is formed thicker than the peripheral region, and the connecting portion is formed to the same thickness as the peripheral region. Further, the thickness from the first surface to the second surface of the support portion is formed with the same thickness as the thickness from one main surface to the other main surface of the excitation region.

  In the piezoelectric vibrating piece according to the fourth aspect, in the first aspect and the second aspect, the thickness from the first surface to the second surface of the support portion is larger than the thickness from one main surface to the other main surface of the excitation region. It is formed thick.

  In the fourth aspect, the piezoelectric vibrating piece according to the fifth aspect is the same thickness as the vibrating portion at the location where the connecting portion is connected to the vibrating portion, and the same thickness as the supporting portion at the location where the connecting portion is connected to the supporting portion, The thickness gradually increases from the location connected to the vibrating portion to the location connected to the support portion.

  A piezoelectric device according to a sixth aspect includes the piezoelectric vibrating piece according to the first to fifth aspects and a connection electrode electrically connected to the extraction electrode drawn out to the support portion via a conductive adhesive. A package on which the piece is placed; and a lid that is connected to the package and forms a sealed space for sealing the piezoelectric vibrating piece.

  According to a seventh aspect of the piezoelectric device, in the sixth aspect, the support portion has two connection locations where the extraction electrode is connected to the connection electrode, and one end of the connection end that connects the support portion and the vibration portion is connected. The other connection location is arranged between the locations.

  In the piezoelectric device according to the eighth aspect, in the sixth aspect and the seventh aspect, an integrated circuit for controlling the piezoelectric vibrating piece is placed on the package.

  According to the piezoelectric vibrating piece and the piezoelectric device of the present invention, a supporting stress is applied to the vibrating portion by not providing a connecting portion between the supporting portion and the vibrating portion between the connection portions where the supporting portion of the piezoelectric vibrating piece and the package are connected. Can be prevented, and the influence of the support stress on the vibration can be eliminated.

1 is an exploded perspective view of a piezoelectric device 100. FIG. It is AA sectional drawing of FIG. FIG. 4A is a perspective view of the piezoelectric vibrating piece 130. FIG. 4B is a plan view of the piezoelectric vibrating piece 130. FIG. 3A is a plan view of the package 120. FIG. FIG. 4B is a plan view of the package 120 on which the piezoelectric vibrating piece 130 is placed. FIG. 6A is a plan view of the piezoelectric vibrating piece 230. FIG. 6B is a plan view of the piezoelectric vibrating piece 330. FIG. 6C is a plan view of the piezoelectric vibrating piece 430. (A) is a perspective view of the piezoelectric vibrating piece 530. (B) is BB sectional drawing of Fig.6 (a). FIG. 6C is a cross-sectional view of the piezoelectric vibrating piece 630. (A) is a plan view of the piezoelectric vibrating piece 730. (B) is CC sectional drawing of Fig.7 (a). 2 is a schematic sectional view of a piezoelectric device 800. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the scope of the present invention is not limited to these forms unless otherwise specified in the following description.

(First embodiment)
<Overall Configuration of Piezoelectric Device 100>
FIG. 1 is an exploded perspective view of the piezoelectric device 100. The piezoelectric device 100 is formed by a piezoelectric vibrating piece 130, a lid 110, and a package 120. As the piezoelectric vibrating piece 130, for example, an AT-cut crystal vibrating piece is used. The AT-cut quartz crystal resonator element has a main surface (XZ plane) inclined at 35 degrees 15 minutes from the Z axis in the Y axis direction around the X axis of the crystal axis (XYZ). In the following description, the new axes tilted with respect to the axial direction of the AT-cut quartz crystal vibrating piece are used as the Y ′ axis and the Z ′ axis. That is, in the piezoelectric device 100, the long side direction of the piezoelectric device 100 is described as the X-axis direction, the height direction of the piezoelectric device 100 is defined as the Y′-axis direction, and the direction perpendicular to the X and Y′-axis directions is described as the Z′-axis direction. .

  In the piezoelectric device 100, the piezoelectric vibrating piece 130 is placed in the recess 121 formed on the + Y′-axis side of the package 120, and the lid 110 is bonded to the + Y′-axis side surface of the package 120 so as to seal the recess 121. Is formed. The piezoelectric device 100 is a surface-mount type piezoelectric device, and is used by being mounted on a printed circuit board or the like via solder (not shown).

  The piezoelectric vibrating piece 130 is formed by a vibrating portion 131 that vibrates at a predetermined frequency, a support portion 132 formed outside the vibrating portion 131, and a connecting portion 133 that connects the vibrating portion 131 and the supporting portion 132. ing. A pair of excitation electrodes 134 is formed on the vibration part 131, and an extraction electrode 135 is extracted from each excitation electrode 134. The extraction electrode 135 is extracted to the support portion 132 through the connecting portion 133.

  The surface on the −Y′-axis side of the package 120 is a mounting surface 126a on which the piezoelectric device 100 is mounted, and a pair of mounting terminals 125 (see FIG. 2) is formed on the mounting surface 126a. The package 120 is formed in a rectangular shape having a long side parallel to the X axis and a short side parallel to the Z ′ axis. At the four corners of the outer wall of the package 120, a castellation 127a that is recessed inside the package 120 is formed, and at the center on the short side of the outer wall, a castellation 127b is formed. A part of the mounting terminal 125 is formed in the castellation 127b.

  A recess 121 that is recessed in the −Y′-axis direction is formed on the surface of the package 120 on the + Y′-axis side. The recess 121 has a bottom surface 126b which is a surface opposite to the mounting surface 126a and is a surface on the −Y′-axis side of the recess 121, and the mounting portion on which the piezoelectric vibrating piece 130 is mounted on the bottom surface 126b. 123 is formed. An electrode pad 124 that is electrically connected to the mounting terminal 125 is formed on the surface at the + Y′-axis side of the mounting portion 123. A bonding surface 122 that is bonded to the lid 110 is formed around the recess 121 of the package 120.

  The package 120 is composed of three layers, and each layer is formed of ceramics, for example. On the −Y′-axis side of the package 120, a first layer 120a formed in a planar shape is disposed. The surface on the −Y′-axis side of the first layer 120a is a mounting surface 126a, and the mounting terminals 125 are formed. The second layer 120b is disposed on the surface on the + Y′-axis side of the first layer 120a. A through hole that forms a part of the recess 121 is formed in the center of the second layer 120b. Further, the second layer 120 b forms a placement portion 123 in the recess 121. The third layer 120c is disposed on the surface at the + Y′-axis side of the second layer 120b. A through hole that forms a part of the recess 121 is formed in the center of the third layer 120c. A bonding surface 122 is formed on the surface at the + Y′-axis side of the third layer 120c.

  The lid 110 is formed as a flat plate. The lid 110 is bonded to the bonding surface 122 on the + Y′-axis side surface of the package 120 via a sealing material 142 (see FIG. 2), thereby sealing the concave portion 121 of the package 120.

  FIG. 2 is a cross-sectional view taken along the line AA of FIG. In the piezoelectric device 100, the lid 110 is bonded to the bonding surface 122 of the package 120 via the sealing material 142, so that the recess 121 of the package 120 is sealed. At the end of the sealed recess 121 on the −X axis side, a mounting portion 123 having an electrode pad 124 formed on the surface on the + Y ′ axis side is formed. A support portion 132 of the piezoelectric vibrating piece 130 is fixed to the mounting portion 123 via a conductive adhesive 141. In addition, the extraction electrode 135 formed on the support portion 132 and the electrode pad 124 formed on the placement portion 123 are electrically connected via a conductive adhesive 141. The electrode pad 124 penetrates the mounting portion 123 or is connected to a part of the mounting surface 126a of the package 120 and a part of the castellation 127b via a connection electrode 124a formed on the surface of the first layer 120a on the + Y′-axis side or the like. The mounting terminal 125 to be formed is electrically connected. For the electrodes such as the electrode pad 124, the connection electrode 124a, and the mounting terminal 125 formed on the package 120, for example, a tungsten layer is formed on ceramics, and a nickel layer is formed thereon as a base plating, and further finishes thereon. It is formed by forming a gold layer as plating.

  FIG. 3A is a perspective view of the piezoelectric vibrating piece 130. The vibrating portion 131 of the piezoelectric vibrating piece 130 is formed in a rectangular shape having long sides extending in the X-axis direction and short sides extending in the Z′-axis direction. A rectangular excitation electrode 134 is formed on each of the surface on the + Y′-axis side and the surface on the −Y′-axis side of the vibration unit 131. Further, a support part 132 that extends away from the vibration part 131 and extends in the Z′-axis direction is formed on the −X-axis side of the vibration part 131, and the −Z′-axis side of the + X-axis side of the support part 132 And the end portion on the −Z′-axis side of the −X-axis side of the vibrating portion 131 are connected by a connecting portion 133 that extends in the X-axis direction. The thickness of the vibration part 131, the support part 132, and the connecting part 133 in the Y′-axis direction are all equal.

  An extraction electrode 135 is extracted from each excitation electrode 134 formed in the vibration part 131. The extraction electrode 135 extracted from the excitation electrode 134 formed on the surface at the + Y′-axis side of the vibration part 131 passes through the surface at the + Y′-axis side of the coupling part 133 and reaches the surface at the + Y′-axis side of the support part 132. After being pulled out and extending the support part 132 in the + Z′-axis direction to the vicinity of the end of the support part 132 on the + Z′-axis side, the −Y′-axis of the support part 132 via the −X-axis side surface of the support part 132 It is pulled out to the side surface. In addition, the extraction electrode 135 extracted from the excitation electrode 134 formed on the surface at the −Y′-axis side of the vibrating portion 131 passes through the surface at the −Y′-axis side of the coupling portion 133 to −Y ′ of the support portion 132. It is pulled out to the surface on the shaft side, extends in the + Z ′ axis direction of the support portion 132, and is pulled out to the surface on the −Y ′ axis side of the support portion 132. In FIG. 3A, the end 135a of each extraction electrode 135 extracted to the surface at the −Y′-axis side of the support portion 132 is shown.

  FIG. 3B is a plan view of the piezoelectric vibrating piece 130. In the piezoelectric vibrating piece 130, L <b> 1 is formed to be shorter than L <b> 2, where L <b> 1 is the length of the vibrating portion 131 in the Z′-axis direction and L <b> 2 is the length of the vibrating portion 131 in the X-axis direction. Further, assuming that the entire length of the piezoelectric vibrating piece 130 in the X-axis direction is L3, L3 is formed longer than L2. In the piezoelectric vibrating piece 130, the length of the support portion 132 in the Z′-axis direction is also formed at L <b> 1. In the piezoelectric vibrating piece 130, a through groove 136 that penetrates the piezoelectric vibrating piece 130 in the Y′-axis direction is formed in a region other than the connection portion 133 between the vibrating portion 131 and the support portion 132.

  The extraction electrodes 135 extracted from the excitation electrodes 134 formed on the surfaces on the + Y′-axis side and the −Y′-axis side of the piezoelectric vibrating piece 130 are preferably formed so as not to overlap each other in the Y′-axis direction. By forming the extraction electrode 135 so as not to overlap in the Y′-axis direction, generation of electrostatic capacitance between the extraction electrodes 135 can be suppressed, and an increase in the crystal impedance (CI) value of the piezoelectric vibrating piece 130 can be suppressed. .

  FIG. 4A is a plan view of the package 120. On the + Z′-axis side and the −Z′-axis side near the center of the long side of the bottom surface 126b, a pair of placement parts 123 on which electrode pads 124 are formed are arranged. In addition, a connection electrode 124 a is formed so as to electrically connect the electrode pad 124 and the mounting terminal 125. The pair of placement portions 123 are disposed at positions that overlap the end 135 a of the extraction electrode 135 in the Y′-axis direction when the piezoelectric vibrating piece 130 is placed in the recess 121.

  In the package 120, castellations 127 a and castellations 127 b that are recessed toward the recess 121 are formed at the four corners of the outer wall and the center of the outer wall on the short side of the package 120. The package 120 is formed by being cut individually after the plurality of packages 120 are formed on the ceramic sheet, but the corners of each package 120 may be cut off during cutting. The castellation 127a is formed to prevent the package 120 from being damaged due to such chipping or the like. Further, the castellation 127 b is formed in order to form a part of the mounting terminal 125 also on the side surface of the package 120. The piezoelectric device 100 is mounted on a printed circuit board or the like via solder, and this solder also adheres to a mounting terminal 125 formed on the side surface of the piezoelectric device 100. Therefore, the joining state of the solder can be confirmed through the solder attached to the mounting terminal 125 formed on the side surface of the piezoelectric device 100.

  FIG. 4B is a plan view of the package 120 on which the piezoelectric vibrating piece 130 is placed. The piezoelectric vibrating piece 130 is electrically connected by joining the end 135a of each extraction electrode 135 drawn to the surface on the −Y′-axis side of the support portion 132 and the electrode pad 124 with the conductive adhesive 141. . That is, the piezoelectric vibrating piece 130 is fixed to the mounting portion 124 as a connection location where the end 135a of each extraction electrode 135 is connected to each connection electrode 124a. In the piezoelectric vibrating piece 130, support stress is generated between the ends 135 a of the respective extraction electrodes 135 to which the piezoelectric vibrating piece 130 is fixed, and in FIG. 4B, the main range in which this support stress is generated along the alternate long and short dash line 150. Is surrounded.

  In piezoelectric devices, frequency temperature characteristics, crystal impedance (CI), frequency reproducibility, aging, etc. may deteriorate due to stress generated when the piezoelectric vibrating piece is fixed. It is caused by being transmitted to.

  In the piezoelectric device 100, as shown in FIG. 4B, the region where the supporting stress is generated surrounded by the alternate long and short dash line 150 and the vibrating portion 131 are separated from each other by the through groove 136, and the region surrounded by the alternate long and short dash line 150 is the most. Since the support part 132 and the vibration part 131 are connected to each other at the end on the −Z ′ axis side of the separated support part, the support stress generated in the support part 132 is hardly transmitted to the vibration part 131. In the piezoelectric device 100, when the piezoelectric vibrating piece 130 is placed on the package 120, heat is applied to the piezoelectric vibrating piece 130 through the conductive adhesive 141. However, the piezoelectric vibrating piece 130 is formed with a through groove 136, which is one point. Since the region where the supporting stress is generated surrounded by the chain line 150 and the vibrating portion 131 are separated from each other by the through groove 136, it is possible to prevent the stress caused by such thermal hysteresis from affecting the vibrating portion 131. It is. As a result, the frequency temperature characteristics, crystal impedance (CI), frequency reproducibility, aging, and the like of the piezoelectric device are prevented from deteriorating.

Conventionally, a soft silicon-based conductive adhesive has been used to relieve the stress caused by the conductive adhesive, but the bonding becomes unstable with a silicon-based conductive adhesive. In some cases, frequency changes and bonding defects occurred. Further, when a silicon-based adhesive is used, there is a problem that a change with time in vibration characteristics becomes large due to a siloxane volatilization problem peculiar to the silicon-based adhesive. In the piezoelectric device 100, since the conductive adhesive is bonded to the support portion 132 of the piezoelectric vibrating piece 130, the influence of stress on the vibrating portion 131 is weakened.
A material harder than a silicon-based conductive adhesive can be used for the conductive adhesive, whereby the piezoelectric vibrating piece 130 can be stably bonded. Therefore, it is possible to prevent the occurrence of frequency changes and bonding defects.

  Further, in the piezoelectric vibrating piece 130, the support portion 132 is formed only on one side of the vibrating portion 131. Therefore, the size of the vibration part 131 can be kept as large as possible, and an increase in equivalent resistance and a reduction in the resonance Q value can be minimized.

(Second Embodiment)
The shape of the piezoelectric vibrating piece and the configuration of the piezoelectric device can be variously formed. Hereinafter, modified examples of the piezoelectric vibrating piece and the piezoelectric device will be described. In the following description, the same parts as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and the description thereof is omitted.

<Configuration of Piezoelectric Vibrating Piece 230>
FIG. 5A is a plan view of the piezoelectric vibrating piece 230. The piezoelectric vibrating piece 230 includes a vibrating part 131, a connecting part 133, and a support part 232. The connecting portion 133 connects the end on the −Z′-axis side of the −X-axis side of the vibrating portion 131 and the end on the −Z′-axis side of the + X-axis side of the support portion 232. The support portion 232 has a length in the Z′-axis direction of L4. L4 is shorter than the length L1 of the vibrating part 131 in the Z′-axis direction and longer than half the length of L1. Further, an extraction electrode 235 is drawn out from the excitation electrode 134 formed on the surface at the + Y′-axis side to the surface at the + Y′-axis side of the support portion 232, and the support portion 232 is further extended in the + Z′-axis direction. After extending to near the end portion on the + Z′-axis side, the support portion 232 is pulled out to the −Y′-axis side surface of the support portion 232 via the −X-axis side surface. The end of the extraction electrode 235 on the surface at the −Y′-axis side of the support portion 232 is an end 235a. A conductive adhesive 141 is applied to the end 235a of the extraction electrode 235 on the surface on the −Y′-axis side of the support portion 232 of the extraction electrode 235 and the end 135a of the extraction electrode 135 to apply to a package (not shown). Fixed.

  In the piezoelectric vibrating piece 230, the entire length of the extraction electrode 235 can be shortened by forming the support portion 232 with a short length in the Z′-axis direction. Thereby, since the electrical resistance value of the whole extraction electrode 235 falls, it can form so that the crystal impedance (CI) value of a piezoelectric vibrating piece may become lower. Further, it is desirable that the length L4 of the support portion 232 be longer than half the length L1 that is the length of the vibrating portion 131 in the Z′-axis direction. When the length of L4 is shorter than half the length of L1, the distance between the end 135a of the extraction electrode 135 and the end 235a of the extraction electrode 235 is shortened, so that a short circuit of the electrode must be taken into account. This is because the bonding region of the adhesive is limited and the fixing of the piezoelectric vibrating piece 230 may become unstable.

<Configuration of Piezoelectric Vibrating Piece 330>
FIG. 5B is a plan view of the piezoelectric vibrating piece 330. The piezoelectric vibrating piece 330 includes a vibrating part 331, a connecting part 333, and a support part 332. The vibrating portion 331 is formed in a rectangular shape having long sides extending in the X-axis direction and short sides extending in the Z′-axis direction. The support portion 332 is formed so as to extend in the X-axis direction, and is disposed on the + Z′-axis side of the vibration portion 331 so as to be separated from the vibration portion 331. Therefore, a through groove 336 is formed between the vibration part 331 and the support part 332. Further, the −X-axis side end of the + Z′-axis side of the vibration part 331 and the −X′-side end of the support part 332 on the −Z′-axis side extend in the Z′-axis direction. The parts 333 are connected. Further, when the length of the piezoelectric vibrating piece 330 in the X-axis direction is L5 and the length in the Z′-axis direction is L6, L5 is formed longer than L6. Further, the lengths of the vibrating portion 331 and the support portion 332 in the X-axis direction are each formed as L5.

  Excitation electrodes 334 are respectively formed on the main surfaces of the vibration part 331 on the + Y′-axis side and the −Y′-axis side, and the extraction electrode 335 is drawn from each excitation electrode 334 to the support part 332. The extraction electrode 335 extracted from the excitation electrode 334 formed on the surface on the + Y′-axis side is extracted to the support portion 332 through the surface on the + Y′-axis side of the coupling portion 333, and further + Y ′ of the support portion 332. The surface on the shaft side extends in the + X-axis direction, and is drawn out to the surface on the −Y′-axis side through the side surface on the + Z′-axis side. Further, the extraction electrode 335 extracted from the excitation electrode 334 formed on the surface at the −Y′-axis side is extracted to the support portion 332 through the surface at the −Y′-axis side of the connecting portion 333, and the support portion 332. To the surface on the −Y′-axis side. The piezoelectric vibrating piece 330 is placed on a package (not shown) by the conductive adhesive 141 at an end 335 a formed on the surface at the −Y′-axis side of the support portion 332 of each extraction electrode 335. Therefore, in the package on which the piezoelectric vibrating piece 330 is placed, a pair of placement portions are formed on the + Z ′ axis side in the recess.

  In the piezoelectric vibrating piece 330, since the support portion 332 extends in the long side direction of the vibrating portion 331, the interval between the ends 335 a of the extraction electrodes 335 can be widened. Therefore, by increasing the area of the end 335a of each extraction electrode 335, the area to which the conductive adhesive 141 is applied can be increased, so that the contact area between the piezoelectric vibrating piece 330 and the conductive adhesive 141 is increased. Thus, the piezoelectric vibrating piece 330 can be strongly fixed to the package.

<Configuration of Piezoelectric Vibrating Piece 430>
FIG. 5C is a plan view of the piezoelectric vibrating piece 430. The piezoelectric vibrating piece 430 includes a vibrating portion 331, a connecting portion 333, and a support portion 432. The connection portion 333 connects the end portion on the −X-axis side of the side on the + Z′-axis side of the vibration portion 331 and the end portion on the −X-axis side of the side on the −Z′-axis side of the support portion 432. The support portion 432 has a length in the X-axis direction of L7. L7 is shorter than the length L5 of the vibration part 332 in the X-axis direction and longer than half the length of L5. Further, the extraction electrode 335 extracted from the excitation electrode 334 formed on the surface on the + Y′-axis side is extracted to the support portion 432 through the surface on the + Y′-axis side of the connecting portion 333, and further, The surface on the + Y′-axis side extends in the + X-axis direction, and is drawn out to the surface on the −Y′-axis side through the side surface on the + Z′-axis side. The conductive adhesive 141 is applied to the end 435a of the extraction electrode 435 on the surface on the −Y′-axis side of the support portion 432 of the extraction electrode 435 and the end 335a of the extraction electrode 335, and then fixed to the package.

  In the piezoelectric vibrating piece 430, similarly to the piezoelectric vibrating piece 230, by appropriately adjusting the length of the support portion 432 in the X-axis direction, the resistance value of the extraction electrode 435 is lowered to reduce the crystal impedance (CI) value. It can be lowered and strengthened to the package.

<Configuration of Piezoelectric Vibrating Piece 530>
FIG. 6A is a perspective view of the piezoelectric vibrating piece 530. The piezoelectric vibrating piece 530 is formed by the vibrating portion 131, the connecting portion 133, and the support portion 532. The support portion 532 is formed to have a longer length in the Y′-axis direction than the support portion 132 (see FIG. 3A), but the other portions are the same as the support portion 132. Therefore, the planar shape of the piezoelectric vibrating piece 530 is the same as that of the piezoelectric vibrating piece 130 (see FIG. 3B). The connecting portion 133 is connected to an end on the −Z′-axis side of the −X-axis side of the vibrating portion 131 and a corner on the + Y′-axis side on the −Z′-axis side of the + X-axis side surface of the support portion 532. ing. From each excitation electrode 134 formed in the vibration part 131, the extraction electrode 535 is drawn to the surface on the −Y′-axis side of the support part 532.

  FIG.6 (b) is BB sectional drawing of Fig.6 (a). When the thickness of the vibrating portion 131 and the connecting portion 133 in the Y′-axis direction is L8, and the thickness of the support portion 532 in the Y′-axis direction is L9, L9 is larger than L8. In the piezoelectric device 100 (see FIG. 2), the mounting portion 123 is provided so that the piezoelectric vibrating piece 130 does not contact the first layer 120a of the package 120. However, the piezoelectric vibrating piece 530 has a thick support portion. Thereby, even if the mounting part 123 is not formed in the package, the vibrating part 133 can be placed in the package so as not to contact the first layer 120a.

<Configuration of Piezoelectric Vibrating Piece 630>
FIG. 6C is a cross-sectional view of the piezoelectric vibrating piece 630. The vibrating part 131, the connecting part 633, and the support part 532 are formed. Except for the connecting portion 633, the piezoelectric vibrating piece 530 and the piezoelectric vibrating piece 630 are the same, and the planar shape is also the same. The connecting portion 633 is formed such that the thickness of the portion connected to the vibrating portion 131 is L8 and the thickness of the portion connected to the support portion 532 is L9. In addition, the connecting portion 633 is formed so that the thickness gradually increases from a portion connected to the vibrating portion 131 to a portion connected to the support portion 532. In the piezoelectric vibrating piece 630, the strength of the connecting portion 633 is enhanced by forming the connecting portion 633 thick in accordance with the thickness of the support portion 532 as described above.

<Configuration of Piezoelectric Vibrating Piece 730>
FIG. 7A is a plan view of the piezoelectric vibrating piece 730. The piezoelectric vibrating piece 730 includes a vibrating portion 731, a connecting portion 133, and a support portion 732. The vibration part 731 is formed by an excitation region 731a that is formed with an excitation electrode 134 and vibrates at a predetermined frequency, and a peripheral region 731b that is formed so as to surround the excitation region 731a.

  FIG.7 (b) is CC sectional drawing of Fig.7 (a). In the vibration unit 731, excitation regions 731 a are formed on both main surfaces on the + Y′-axis side and the −Y′-axis side. When the thickness in the Y′-axis direction of the peripheral region 731b is L8, each excitation region 731a is formed from the peripheral region 731b to a thickness L11. Further, the thickness of the support portion 732 in the Y′-axis direction and the thickness of the vibration portion 731 in the Y′-axis direction are formed to be equal. Therefore, in the piezoelectric vibrating piece 730, when the thickness of the support portion 732 in the Y′-axis direction is L10, as shown in FIG. 7B, L8 and twice the thickness L11 of the excitation region 731b. The total is formed to be L10.

  In the piezoelectric vibrating piece 730, since the central region of the vibrating portion 731 is formed in a thick mesa shape, generation of unnecessary vibration of the piezoelectric vibrating piece 730 can be suppressed, and the crystal impedance (CI) value can be reduced.

<Configuration of Piezoelectric Device 800>
FIG. 8 is a schematic sectional view of the piezoelectric device 800. The piezoelectric device 800 includes a piezoelectric vibrating piece 130, a lid 110, a package 820, and an integrated circuit 850. The package 820 includes a recess 821 having an opening on the + Y′-axis side, and is formed of a first layer 820a, a second layer 820b, and a third layer 820c. The first layer 820a, the second layer 820b, and the third layer 820c correspond to the first layer 120a, the second layer 120b, and the third layer 120c of the package 120, but a package for mounting the integrated circuit 850. The first layer 120a, the second layer 120b, and the third layer 120c of 120 are different in size, wiring of electrodes, and the like.

  A mounting terminal 825 is formed on the surface of the first layer 820a on the −Y′-axis side, and the integrated circuit 850 is placed in the recess 821 on the surface on the + Y′-axis side. The mounting terminal 825 includes, for example, six terminals, and each terminal is electrically connected to the integrated circuit 850 to mediate the receipt of power from the outside and the output of a frequency signal to the outside of the piezoelectric device 800. The integrated circuit 850 further controls the piezoelectric vibrating piece 130 by being electrically connected to the piezoelectric vibrating piece 130 via a connection electrode 824 a formed in the recess 821 of the package 820. The piezoelectric vibrating piece 130 is placed on a placement portion 823 formed in the recess 821. The recess 821 is sealed by the lid 110.

  As described above, the optimal embodiment of the present invention has been described in detail. However, as will be apparent to those skilled in the art, the present invention can be implemented with various modifications and variations within the technical scope thereof. Moreover, the features of each embodiment can be implemented in various combinations.

  Furthermore, in the above-described embodiment, the vibrating portion is rectangular, but may be other shapes such as a tuning fork shape, an elliptical shape, and a circular shape. Further, although the piezoelectric vibrating piece is an AT cut crystal, a crystal such as a Z cut or a BT cut may be used. Moreover, although the piezoelectric vibrating piece is formed of quartz, a piezoelectric material other than quartz, for example, lithium tantalate, lithium niobate, or piezoelectric ceramic may be used.

DESCRIPTION OF SYMBOLS 100, 800 ... Piezoelectric device 110 ... Lid 120, 820 ... Package 120a ... 1st layer 120b ... 2nd layer 120c ... 3rd layer 121, 821 ... Recessed part 122 ... Bonding surface 123, 823 ... Mounting part 124 ... Electrode pad 124a , 824a ... connection electrode 125, 825 ... mounting terminal 126a ... mounting surface 126b ... bottom face 127a, 127b ... castellation 130, 230, 330, 430, 530, 630, 730 ... piezoelectric vibrating piece 131, 331, 731 ... vibrating part 132 232, 332, 432, 532, 732 ... support part 133, 333, 633 ... connection part 134, 334 ... excitation electrode 135, 235, 335, 435 ... extraction electrode 135a, 235a, 335a, 435a ... -Y of the support part 'Draw out on the shaft side End of the extraction electrode 136,336 ... through groove 141 ... conductive adhesive 142 ... sealing member 731a ... excitation region 731b ... peripheral region 850 ... integrated circuits

Claims (8)

A vibrating portion having a pair of rectangular main surfaces having a long side and a short side, and a pair of excitation electrodes formed on the pair of main surfaces to vibrate at a predetermined frequency;
A support portion that is spaced apart from the vibrating portion and extends in parallel with the long side or the short side, and has a first surface parallel to the main surface and a second surface opposite to the first surface;
A connecting portion extending perpendicularly to the long side or the short side so as to connect one end of the support portion and the end of the long side or the short side;
A piezoelectric vibrating piece in which an extraction electrode is drawn from each excitation electrode to the second surface of the support portion.   The length of the support part is equal to or longer than the length of the long side or the short side that the support part is spaced apart and extends in parallel, and the long side or the short side that the support part is spaced apart and extends in parallel. The piezoelectric vibrating piece according to claim 1, wherein the piezoelectric vibrating piece is not longer than a side length. The vibration unit has an excitation region where the excitation electrode is formed and a peripheral region surrounding the excitation region,
The excitation region is formed thicker than the peripheral region,
The connecting portion is formed to the same thickness as the peripheral region,
The thickness from the said 1st surface of the said support part to the said 2nd surface is formed with the same thickness as the thickness from the one main surface of the said excitation area | region to the other main surface. The piezoelectric vibrating piece according to the description.   The thickness from the said 1st surface of the said support part to the said 2nd surface is formed more thickly than the thickness from one main surface of the said excitation area | region to the other main surface. Piezoelectric vibrating piece.   The connecting portion has the same thickness as the vibrating portion at a location where the connecting portion is connected to the vibrating portion, and has the same thickness as the supporting portion where the connecting portion is connected to the vibrating portion. The piezoelectric vibrating piece according to claim 4, wherein the thickness of the piezoelectric vibrating piece gradually increases from a portion connected to the support portion. The piezoelectric vibrating piece according to any one of claims 1 to 5,
A connection electrode electrically connected to the extraction electrode drawn out to the support portion via a conductive adhesive, and a package on which the piezoelectric vibrating piece is placed;
And a lid that is connected to the package and forms a sealed space for sealing the piezoelectric vibrating piece.   The support part has two connection points where the extraction electrode is connected to the connection electrode, and the other part between the connection part that connects the support part and the vibration part and the one connection part. The piezoelectric device according to claim 6, wherein the connection portion is disposed. The piezoelectric device according to claim 6, wherein an integrated circuit that controls the piezoelectric vibrating piece is placed on the package.

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