JP2019121854A - Piezoelectric vibration device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration device having a sandwich structure capable of improving the bonding strength with an external circuit board. A crystal oscillator 101 includes a crystal diaphragm 2, a first sealing member 3 and a second sealing member 4 that cover a first excitation electrode 221 and a second excitation electrode 222 of the crystal diaphragm 2. It is provided. A substantially rectangular parallelepiped package 12 is formed by joining the first sealing member 3, the crystal diaphragm 2, and the second sealing member 4. The package 12 is provided with an internal space 13 in which the vibrating portion 23 of the crystal diaphragm 2 is hermetically sealed. The joining material 11 that airtightly seals the vibrating portion 23 of the crystal diaphragm 2 is formed in an annular shape in a plan view, and is provided along the outer peripheral edge of the package 12 at a portion other than the four corners of the package 12. .. In addition, external electrode terminals are formed at the four corners of the other main surface of the second sealing member, and external electrode side terminals are provided on the side surfaces of the second sealing member. [Selection diagram] Fig. 7

Description

  The present invention relates to a piezoelectric vibration device.

  2. Description of the Related Art In recent years, the operating frequency of various electronic devices has been increased and the size of packages has been reduced (particularly, the reduction in height). Therefore, as the frequency is increased and the package is miniaturized, the piezoelectric vibration device (for example, a crystal oscillator or the like) is also required to cope with the frequency and size of the package.

  In this type of piezoelectric vibration device, the housing is configured by a substantially rectangular parallelepiped package. This package comprises a first sealing member and a second sealing member made of glass or quartz, and a quartz crystal plate made of quartz and having excitation electrodes formed on both principal surfaces, and the first sealing member and the second sealing member (2) The excitation electrode of the crystal vibrating plate disposed inside (internal space) of the package is hermetically sealed (see, for example, Patent Document 1). Hereinafter, such a laminated form of the piezoelectric vibration device is referred to as a sandwich structure.

Unexamined-Japanese-Patent No. 2010-252051

  However, in the piezoelectric vibration device of the sandwich structure whose size has been advanced, the effective area of the external electrode terminal formed on the bottom surface of the sealing member is also smaller and limited compared to the piezoelectric vibration device of the conventional ceramic package. In addition, the formation of the external electrode terminal is likely to adversely affect the electrical characteristics.

  As a result, as a piezoelectric vibration device used in applications requiring impact resistance performance such as in-vehicle applications, it is difficult to secure the bonding strength with an external circuit board by a conductive bonding material such as solder, and thus the configuration becomes unsuitable. It was

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a piezoelectric vibration device having a sandwich structure capable of improving the bonding strength with an external circuit board.

In the present invention, means for solving the above-mentioned problems are configured as follows. That is, the present invention
A piezoelectric vibration plate having a first excitation electrode formed on one main surface of a substrate and a second excitation electrode formed on the other main surface of the substrate to be paired with the first excitation electrode; (1) A first sealing member covering an excitation electrode and a second sealing member covering the second excitation electrode of the piezoelectric diaphragm are provided, wherein the other principal surface of the first sealing member and the piezoelectric diaphragm A substantially rectangular package is formed by bonding one main surface and the one main surface of the second sealing member and the other main surface of the piezoelectric diaphragm, and the package includes the package. In a piezoelectric vibration device provided with an internal space in which the vibration portion of the piezoelectric vibration plate including the first excitation electrode and the second excitation electrode is airtightly sealed, sealing for airtightly sealing the vibration portion of the piezoelectric vibration plate The portion is annularly formed in plan view, and from the outer peripheral edge at the four corners of the package The device according to the present invention has the spaced apart portion and the outer peripheral edge portion provided along the outer peripheral edge of the package in a portion other than the separated portion, and is not electrically connected to the respective excitation electrodes. [2] A plurality of external electrode terminals electrically connected to the external circuit board are formed at four corners of the other main surface of the sealing member, and side surfaces of the second sealing member are connected to the external electrode terminal An external electrode side surface terminal is provided in a region where the separation portion of the sealing portion is formed.

  According to the above configuration, the sealing portion of the package constitutes an isolation portion of the sealing portion at only four corners of the outer peripheral edge, and the other is configured as an outer peripheral edge provided along the outer peripheral edge of the package Therefore, the space of the outer peripheral edge portion of the sealing portion can be used as the arrangement space of the vibrating portion of the piezoelectric diaphragm, and the space of the internal space for hermetically sealing the vibrating portion of the piezoelectric diaphragm can be made as large as possible. This makes it possible not only to use the vibrating portion with the largest possible configuration, but also to improve the degree of freedom in the design of the vibrating portion and to design vibrating portions of various characteristics.

  In addition, since it can be used as an arrangement space of, for example, a through hole or an electrical path in the four corner regions of the package, it is desirable to form an effective area of external electrode terminals for bonding to an external circuit board. it can. In addition, since the external electrode terminals at the four corners of the package can be avoided as much as possible from overlapping with the excitation electrode of the piezoelectric diaphragm disposed near the center of the package in the thickness direction of the package, stray capacitance The adverse effect of external noise can be reduced.

  In addition, since the sealing portion is not electrically connected to each excitation electrode, it is possible to suppress the occurrence of parasitic capacitance due to the connection of the both, and a large amount of variable frequency of the piezoelectric vibration device can be secured.

  In addition, since the external electrode side surface terminal is provided on the side surface of the second sealing member in the region connected to the external electrode terminal and in which the separation portion of the sealing portion is formed, solder (fluid conductive When bonding to the external circuit board using bonding material), not only surface bonding with only the external electrode terminals, but also a fillet part where the solder protrudes along the external electrode side terminals is formed, and the bonding area is increased. Can be enhanced. Moreover, since the fillet portion formed by the solder protruding along the external electrode side surface terminal is located in the region where the separation portion of the sealing portion is formed, it becomes a region where the outer peripheral edge portion of the sealing portion does not exist. There is no short circuit between the external electrode terminal and the sealing portion having a different polarity.

  As described above, even in the piezoelectric vibration device having a sandwich structure, which is small and difficult to secure the effective area of the external electrode terminal, the bonding strength with the external circuit board can be enhanced, and high mechanical performance such as in-vehicle application is required. Can also be used for

  In the above configuration, through holes penetrating between the one main surface and the other main surface of the piezoelectric diaphragm are provided at four corners of the package, and a plurality of main surfaces of the first sealing member are provided. A wiring pattern is formed, and each of the through holes is formed with a through electrode for electrically connecting a part of the plurality of wiring patterns and a part of the plurality of external electrode terminals. Good.

  According to the above configuration, the through holes are disposed outside the sealing portion in plan view, and the through holes can be formed in the piezoelectric diaphragm using spaces at the four corners of the package, and the electrodes are formed in the through holes. By forming, it is possible to electrically connect between the one main surface and the other main surface of the piezoelectric diaphragm.

  In addition, peeling of the four corners of the package is likely to occur in each layer (piezoelectric diaphragm, first sealing member, and second sealing member) of the package due to external force. However, according to this configuration, the sealing portion can be protected from peeling due to an external force by arranging the sealing portion avoiding the four corners of the package.

  In the above configuration, the external electrode side surface terminals may be provided at the corners of four corners of the side surfaces of the second sealing member. The four corners of the package are easily stressed by the external force. However, according to this configuration, it is possible to counter the stress due to the external force by forming the fillet portions of the solder (fluid conductive bonding material) at the four corners of the package and enhancing the bonding strength.

  In the above configuration, the external electrode terminal may not overlap with the excitation electrode of the piezoelectric diaphragm. According to this configuration, it is possible to reduce the adverse effect of stray capacitance and external noise generated in both the external terminal electrode and the excitation electrode.

  In the above configuration, the outer edge of the sealing portion may be octagonal in plan view. According to this configuration, the sealing portion provided in the space other than the four corners of the outer peripheral edge of the package and the through holes provided in the space at the four corners of the package can be arranged more efficiently.

  According to the present invention, in the piezoelectric vibration device having a sandwich structure, it is possible to easily cope with miniaturization, and the bonding strength with an external circuit board can be improved.

FIG. 1 is a schematic configuration diagram showing each configuration of a crystal oscillator according to the present embodiment. FIG. 2 is a schematic plan view of a first sealing member of the crystal oscillator. FIG. 3 is a schematic back view of the first sealing member of the crystal oscillator. FIG. 4 is a schematic plan view of a quartz crystal plate of a quartz oscillator. FIG. 5 is a schematic back view of a quartz crystal plate of a quartz oscillator. FIG. 6 is a schematic plan view of a second sealing member of the crystal oscillator. FIG. 7 is a schematic back view of the second sealing member of the crystal oscillator. FIG. 8 is a schematic perspective view of the back surface side of the second sealing member of the crystal oscillator. FIG. 9 is a schematic plan view showing the positional relationship in plan view between the bonding material in the quartz oscillator, the vibrating portion of the quartz crystal plate, the through holes, and the like. FIG. 10 is a schematic plan view showing a modification of the quartz crystal plate of the quartz oscillator.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a case where the present invention is applied to a crystal oscillator as a piezoelectric vibration device will be described.

  In the crystal oscillator 101 according to the present embodiment, as shown in FIG. 1, the crystal oscillator plate 2 (piezoelectric diaphragm according to the present invention) and the first excitation electrode 221 (see FIG. 4) of the crystal oscillator plate 2 are covered. A first sealing member 3 for hermetically sealing the first excitation electrode 221 formed on the one major surface 211 of the quartz crystal plate 2, and the other major surface 212 of the quartz crystal plate 2 A second sealing member 4 for hermetically sealing a second excitation electrode 222 which covers the two excitation electrodes 222 (see FIG. 5) and is formed in a pair with the first excitation electrode 221; An electronic component element (IC5 in the present embodiment) mounted is provided. The IC 5 as an electronic component element is a one-chip integrated circuit element that constitutes an oscillation circuit together with the crystal vibrating plate 2. In the crystal oscillator 101, the quartz crystal plate 2 and the first sealing member 3 are joined, and the quartz crystal plate 2 and the second sealing member 4 are joined, so that the package 12 having a substantially rectangular parallelepiped sandwich structure is obtained. Configured

  Then, the first sealing member 3 and the second sealing member 4 are joined via the quartz crystal plate 2 to form the inner space 13 of the package 12, and the inner space 13 of the package 12 is made of quartz. The vibrating portion 23 including the first excitation electrode 221 and the second excitation electrode 222 formed on both main surfaces 211 and 212 of the diaphragm 2 is hermetically sealed. The crystal oscillator 101 according to the present embodiment has, for example, a package size of 1.0 × 0.8 mm, and is intended to achieve miniaturization and a reduction in height. Further, with the miniaturization, in the present package 12, conduction of electrodes is achieved using through holes (first to twenty-fifth through holes) described later without forming castellations.

  Next, the quartz crystal plate 2, the first sealing member 3 and the second sealing member 4 constituting the package 12 of the quartz oscillator 101 will be described with reference to FIGS. Here, each member which is configured as a single body and in which the crystal plate 2, the first sealing member 3 and the second sealing member 4 are not joined will be described.

  The crystal vibrating plate 2 is a piezoelectric substrate made of quartz crystal as shown in FIGS. 4 and 5, and both main surfaces (one main surface 211 and the other main surface 212) are formed as flat and smooth surfaces (mirror surface processing) ing.

  A pair of (a pair of) excitation electrodes (a first excitation electrode 221 and a second excitation electrode 222) are formed on both major surfaces 211 and 212 (one major surface 211 and other major surface 212) of the quartz crystal plate 2. . Further, two notches 24 (through shapes) are formed on both main surfaces 211 and 212 so as to surround the pair of first excitation electrodes 221 and second excitation electrodes 222, and the vibrating portion 23 is configured. . The notched portion 24 is formed of a plan view concave shape body 241 (three plan view rectangles formed by extending each two rectangles from both ends of one plan view rectangle in a direction perpendicular to the longitudinal direction of the rectangle) It consists of a plan view body) and a plan view rectangular body 242.

  Then, a lead-out electrode (first lead-out electrode for drawing out the first excitation electrode 221 and the second excitation electrode 222 to the IC 5 in a portion (holding portion) 213 between the plan view concave shape body 241 and the plan view rectangular body 242 An electrode 223 and a second lead electrode 224) are provided. The first excitation electrode 221 and the first lead-out electrode 223 are laminated on the underlying PVD film formed by physical vapor deposition on the one principal surface 211 and laminated on the underlying PVD film by physical vapor deposition. And an electrode PVD film. The second excitation electrode 222 and the second lead-out electrode 224 are laminated by physical vapor deposition on the underlying PVD film and the underlying PVD film formed by physical vapor deposition on the other major surface 212. And an electrode PVD film.

  In the crystal vibrating plate 2, vibration for joining the first sealing member 3 and the second sealing member 4 so as to surround the vibrating portion 23 outward along the vibrating portion 23 of both main surfaces 211 and 212. The side sealing parts 25 are respectively provided. A vibration-side first bonding pattern 251 for bonding to the first sealing member 3 is formed in the vibration-side sealing portion 25 of the main surface 211 of the quartz crystal plate 2. Further, a vibration-side second bonding pattern 252 for bonding to the second sealing member 4 is formed in the vibration-side sealing portion 25 of the other main surface 212 of the quartz crystal plate 2.

  The vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 are annularly formed in a plan view, and the outer edge is formed in a substantially octagonal shape. The first vibration-side bonding pattern 251 and the second vibration-side bonding pattern 252 are provided at portions other than the four corners of the quartz crystal plate 2 in a plan view. In other words, the vibration-side first bonding pattern 251 has the quartz vibration plate 2 at portions other than the separation portions 251 a separated from the outer peripheral edge at the four corners of the quartz crystal plate 2 in plan view and the square portions 251 a of the four corners of the quartz crystal plate 2. And four outer peripheral edge portions 251b provided along the outer peripheral edge. The vibration-side second bonding pattern 252 is an outer peripheral edge of the quartz crystal diaphragm 2 in portions other than the separators 252 a separated from the outer peripheral edge at four corners of the quartz crystal plate 2 in plan view and the separators 252 a at four corners of the quartz crystal diaphragm 2. And four outer peripheral edges 252 b provided along the

  The vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 have the same width, and are provided at the same position in plan view. The internal space 13 is formed inward (inner side) of the first vibration-side bonding pattern 251 and the second vibration-side bonding pattern 252 in plan view. The inner side of the internal space 13 mentioned here means the inner side of the inner peripheral surface of the bonding material 11 strictly without including the bonding material 11 which will be described later. The pair of first excitation electrodes 221 and the second excitation electrodes 222 of the quartz crystal plate 2 are not electrically connected to the first vibration-side bonding pattern 251 and the second vibration-side bonding pattern 252.

  The vibration-side first bonding pattern 251 has a base PVD film 2511 formed by physical vapor deposition on one principal surface 211 and an electrode PVD formed by physical vapor deposition on the base PVD film 2511. And a membrane 2512. The vibration-side second bonding pattern 252 is an underlying PVD film 2521 formed by physical vapor deposition on the other major surface 212 and an electrode PVD formed by physical vapor deposition on the underlying PVD film 2521. And a membrane 2522. That is, the first vibration-side bonding pattern 251 and the second vibration-side bonding pattern 252 have the same configuration, and a plurality of layers are stacked on the vibration-side sealing portion 25 of both main surfaces 211 and 212. A Ti layer (or a Cr layer) and an Au layer are formed by evaporation from the lowermost layer side. Thus, in the vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252, the underlying PVD films 2511 and 2521 are made of a single material (Ti (or Cr)), and the electrode PVD films 2512 and 2225 are It consists of a single material (Au), and the electrode PVD films 2512 and 2522 are thicker than the underlying PVD films 2511 and 2521.

  In addition, the first excitation electrode 221 formed on one principal surface 211 of the quartz crystal plate 2 and the first vibration-side bonding pattern 251 have the same thickness, and the first excitation electrode 221 and the first vibration-side bonding pattern 251 The second excitation electrode 222 and the vibration-side second bonding pattern 252 formed on the other principal surface 212 of the quartz crystal plate 2 have the same thickness. The surfaces (principal surfaces) of 222 and the vibration-side second bonding pattern 252 are made of the same metal. The vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 are non-Sn patterns.

  Here, the first excitation electrode 221, the first extraction electrode 223, and the vibration-side first bonding pattern 251 may have the same configuration, and in this case, the first excitation electrode 221, the first extraction electrode 223 may be formed in the same process. The vibration-side first bonding pattern 251 can be formed at one time. Similarly, the second excitation electrode 222, the second extraction electrode 224, and the vibration-side second bonding pattern 252 may have the same configuration, and in this case, the second excitation electrode 222, the second extraction electrode 224 may be formed in the same process. The vibration-side second bonding pattern 252 can be formed at one time. Specifically, the underlying PVD film and the electrode PVD film are formed by PVD methods such as vacuum evaporation, sputtering, ion plating, MBE and laser ablation (for example, film formation methods for patterning in processing such as photolithography) Thus, film formation can be performed collectively, and the number of manufacturing steps can be reduced, which can contribute to cost reduction.

  As shown in FIGS. 4 and 5, five through holes (first to fifteenth through holes 271 to 275) that penetrate between the one main surface 211 and the other main surface 212 are formed in the quartz crystal plate 2. ing. The eleventh through hole 271 is connected to a sixteenth through hole 351 of the first sealing member 3 and a twenty second through hole 451 of the second sealing member 4 which will be described later. The twelfth through hole 272 is connected to a seventeenth through hole 352 of the first sealing member 3 and a twenty-third through hole 452 of the second sealing member 4 which will be described later. The thirteenth through hole 273 is connected to an eighteenth through hole 353 of the first sealing member 3 and a twenty fourth through hole 453 of the second sealing member 4 which will be described later. The fourteenth through hole 274 is connected to a nineteenth through hole 354 of the first sealing member 3 and a twenty fifth through hole 454 of the second sealing member 4 which will be described later. The fifteenth through hole 275 is connected to the twenty first through hole 356 of the first sealing member 3 through the second lead electrode 224 drawn from the second excitation electrode 222 and the bonding material 14 described later.

  In the first to fifteenth through holes 271 to 275, as shown in FIGS. 1, 4 and 5, through electrodes 71 for conducting the electrodes formed on the one main surface 211 and the other main surface 212 are: They are formed along the inner wall surfaces of the first to fifteenth through holes 271 to 275 respectively. And the central part of each of the 11th-15th through holes 271-275 becomes the penetration part 72 of the hollow state which penetrated between the one principal surface 211 and the other principal surface 212. The connection bonding pattern 73 is formed on the outer periphery of each of the first to fifteenth through holes 271 to 275. The connection bonding pattern 73 is provided on both main surfaces (one main surface 211 and the other main surface 212) of the quartz crystal plate 2.

  The connection bonding pattern 73 has the same configuration as the vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252, and is formed in the same process as the vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252. can do. Specifically, the connection bonding pattern 73 is formed by physical vapor-phase growth on the two main surfaces (one main surface 211 and the other main surface 212) of the quartz crystal plate 2 and the underlying film. An electrode PVD film is formed by physical vapor deposition on the PVD film and laminated.

  The connection bonding pattern 73 for connection of the fifteenth through hole 275 formed on one principal surface 211 of the quartz crystal plate 2 extends along the direction of the arrow A1 in FIG. 4 and the vibration-side first bonding pattern 251 and the notch portion It is provided between 24. The connection bonding pattern 73 for connection of the fifteenth through holes 275 formed in the other principal surface 212 of the quartz crystal plate 2 is integrally formed with the second lead-out electrode 224 drawn from the second excitation electrode 222. In addition, on the first lead-out electrode 223 drawn from the first excitation electrode 221, a connection bonding pattern 73 extending along the direction of the arrow A1 in FIG. 4 is integrally formed, and the connection bonding pattern 73 is The vibration-side first bonding pattern 251 and the notch 24 are provided.

  In the crystal oscillator 101, the first to fourteenth through holes 271 to 274 are formed outside the inner space 13 (outside the outer peripheral surface of the bonding material 11) in a plan view. More specifically, the first to fourteenth through holes 271 to 274 are provided at the four corners of the quartz crystal plate 2 in a plan view. On the other hand, the fifteenth through hole 275 is formed inward of the internal space 13 (inside of the inner peripheral surface of the bonding material 11) in plan view. That is, the fifteenth through holes 275 are provided at portions other than the four corners of the quartz crystal plate 2 in a plan view. The first to fifteenth through holes 271 to 275 are not electrically connected to the first vibration-side bonding pattern 251 and the second vibration-side bonding pattern 252.

For the first sealing member 3, a material having a bending rigidity (second moment of area × Young's modulus) of 1000 [N · mm ² ] or less is used. Specifically, as shown in FIGS. 2 and 3, the first sealing member 3 is a rectangular parallelepiped substrate formed of a single glass wafer, and the other main surface 312 (the first sealing member 3) The surface to be joined to the quartz crystal plate 2 is formed as a flat smooth surface (mirror surface processing). The first sealing member 3 has substantially the same shape and size as the quartz crystal diaphragm 2 in a plan view.

  On the other main surface 312 of the first sealing member 3, a sealing-side first sealing portion 32 for bonding to the crystal vibrating plate 2 is provided. In the first sealing portion 32 of the first sealing member 3, a first sealing pattern 321 for bonding to the quartz crystal plate 2 is formed.

  The first sealing-side bonding pattern 321 is formed in an annular shape in plan view, and the outer edge is formed in a substantially octagonal shape. The sealing-side first bonding pattern 321 is provided in a portion other than the four corners of the first sealing member 3 in a plan view. That is, in the sealing side first bonding pattern 321, in the portions other than the separation portions 321a separated from the outer peripheral edge at the four corners of the first sealing member 3 and the separation portions 321a of the four corners of the first sealing member 3 in plan view. And four outer peripheral edge portions 321 b provided along the outer peripheral edge of the first sealing member 3. The sealing side first bonding pattern 321 has the same width at all positions on the sealing side first sealing portion 32 of the first sealing member 3.

  The first sealing pattern 321 on the sealing side is formed by physical vapor deposition on the underlying PVD film 3211 formed on the first sealing member 3 by physical vapor deposition and on the underlying PVD film 3211. And the formed electrode PVD film 3212. In the present embodiment, Ti (or Cr) is used for the base PVD film 3211, and Au is used for the electrode PVD film 3212. In addition, the first sealing pattern on the sealing side 321 is a non-Sn pattern. Specifically, the first sealing pattern on the sealing side 321 is formed by laminating a plurality of layers on the first sealing portion 32 on the second main surface 312, and the Ti layer (or the bottom layer side) The Cr layer) and the Au layer are formed by evaporation.

  As shown in FIGS. 1 and 2, six electrode patterns 33 including mounting pads for mounting the IC 5 which is an oscillation circuit element are formed on one main surface 311 (surface on which the IC 5 is mounted) of the first sealing member 3 It is done. The six electrode patterns 33 are individually connected to the sixteenth to twenty-first through holes 351 to 356, respectively. The IC 5 is bonded to the electrode pattern 33 by a FCB (Flip Chip Bonding) method using a metal bump (for example, an Au bump or the like) 34. Each electrode pattern 33 has the same configuration as that of the sealing-side first bonding pattern 321, and has an underlying PVD film physically grown on one principal surface 311 by physical vapor deposition, and physically on the underlying PVD film. It consists of an electrode PVD film grown by vapor phase deposition and laminated.

  As shown in FIGS. 1 to 3, the first sealing member 3 has six through holes (sixteenth to twenty first through holes 351 to 356) penetrating between the one main surface 311 and the other main surface 312. It is formed. The sixteenth through holes 351 are connected to the eleventh through holes 271 of the quartz crystal plate 2. The seventeenth through hole 352 is connected to the twelfth through hole 272 of the quartz crystal plate 2. The eighteenth through hole 353 is connected to the thirteenth through hole 273 of the quartz crystal plate 2. The nineteenth through hole 354 is connected to the fourteenth through hole 274 of the quartz crystal plate 2. The twentieth through hole 355 is connected to the first lead electrode 223 drawn from the first excitation electrode 221 of the quartz crystal plate 2 through the bonding material 14. The twenty-first through hole 356 is connected to the fifteenth through hole 275 of the quartz crystal diaphragm 2 via the bonding material 14.

  In the sixteenth to twenty first through holes 351 to 356, as shown in FIGS. 1 to 3, the through electrode 71 for achieving conduction of the electrodes formed on the one main surface 311 and the other main surface 312 is the sixteenth To 21st through holes 351 to 356 are formed along the inner wall surface of each. The central portion of each of the sixteenth to twenty-first through holes 351 to 356 is a hollow through portion 72 penetrating between the one main surface 311 and the other main surface 312. A connection bonding pattern 73 is formed on the outer periphery of each of the sixteenth to twenty first through holes 351 to 356. The connection bonding pattern 73 is provided on the other main surface 312 of the first sealing member 3.

  The connection bonding pattern 73 has the same configuration as the sealing-side first bonding pattern 321, and can be formed by the same process as the sealing-side first bonding pattern 321. Specifically, the connection bonding pattern 73 is formed on the other principal surface 312 of the first sealing member 3 by physical vapor deposition, and the physical vapor phase is formed on the underlying PVD film. It consists of an electrode PVD film grown and laminated. The connection bonding pattern 73 for connection of the twentieth through holes 355 and the twenty first through holes 356 extends along the arrow A1 direction in FIG.

  In the crystal oscillator 101, the sixteenth to nineteenth through holes 351 to 354 are formed outside the inner space 13 (outside the outer peripheral surface of the bonding material 11) in a plan view. More specifically, the sixteenth to nineteenth through holes 351 to 354 are provided at the four corners of the first sealing member 3 in a plan view. On the other hand, the twentieth through holes 355 and the twenty first through holes 356 are formed inward of the internal space 13 (inside of the inner peripheral surface of the bonding material 11) in plan view. That is, the twentieth through holes 355 and the twenty first through holes 356 are provided at portions other than the four corners of the first sealing member 3 in a plan view. The sixteenth to twenty first through holes 351 to 356 are not electrically connected to the first sealing pattern 321 on the sealing side. Further, the six electrode patterns 33 are also not electrically connected to the first sealing pattern 321 on the sealing side.

For the second sealing member 4, a material having a flexural rigidity (second moment of area × Young's modulus) of 1000 [N · mm ² ] or less is used. Specifically, as shown in FIG. 6, the second sealing member 4 is a rectangular parallelepiped substrate formed of a single glass wafer, and one principal surface 411 (quartz crystal vibration of the second sealing member 4) The surface to be joined to the plate 2 is formed as a flat smooth surface (mirror surface processing). The second sealing member 4 has substantially the same shape and size as the quartz crystal diaphragm 2 in a plan view.

  A sealing side second sealing portion 42 for bonding to the quartz crystal plate 2 is provided on one main surface 411 of the second sealing member 4. In the sealing side second sealing portion 42, a sealing side second bonding pattern 421 for bonding to the crystal vibrating plate 2 is formed.

  The sealing-side second bonding pattern 421 is formed in an annular shape in a plan view, and the outer edge is formed in a substantially octagonal shape. The sealing-side second bonding pattern 421 is provided in a portion other than the four corners of the second sealing member 4 in a plan view. That is, the sealing-side second bonding pattern 421 has portions other than the separation portions 421 a separated from the outer peripheral edge at the four corners of the second sealing member 4 in plan view and the separation portions 421 a of the four corners of the second sealing member 4. And four outer peripheral edge portions 421 b provided along the outer peripheral edge of the second sealing member 4. The sealing-side second bonding pattern 421 has the same width at all positions on the sealing-side second sealing portion 42 of the second sealing member 4.

  The sealing-side second bonding pattern 421 is formed by physical vapor-phase growth on the underlying PVD film 4211 formed on the second sealing member 4 by physical vapor-phase growth and on the underlying PVD film 4211. And the formed electrode PVD film 4212. In the present embodiment, Ti (or Cr) is used for the base PVD film 4211, and Au is used for the electrode PVD film 4212. Moreover, the sealing side second bonding pattern 421 is a non-Sn pattern. Specifically, the sealing side second bonding pattern 421 is configured by laminating a plurality of layers on the sealing side second sealing portion 42 of the one main surface 411, and from the lowermost layer side, a Ti layer (or The Cr layer) and the Au layer are formed by evaporation. -

  Four external electrode terminals (first to fourth external electrode terminals 433) electrically connected to the outside are provided on the other main surface 412 of the second sealing member 4 (the outer main surface not facing the quartz crystal diaphragm 2). ~ 436) are provided. The first to fourth external electrode terminals 433 to 436 are located at four corners (four corners) of the other main surface 412 of the second sealing member 4. Further, as shown in FIGS. 7 and 8, the second sealing member except the region where the four external electrode terminals (first to fourth external electrode terminals 433 to 436) are connected to the external electrode side surface terminal described later It is provided at a predetermined distance from the outer peripheral end of the housing 4.

  More specifically, in the region where the outer peripheral edge portion 421b of the sealing-side second bonding pattern 421 (sealing portion) does not exist, the separation portion 421a of the sealing-side second bonding pattern 421 (sealing portion) is formed Only in the region, it is extended to the outer peripheral end of the second sealing member 4 and is connected to an external electrode side terminal described later. These external electrode terminals (first to fourth external electrode terminals 433 to 436) are formed on the other main surface 412 by physical vapor deposition and formed on underlying PVD films 4331 to 4361 and underlying PVD films 4331 to 4361. The electrode PVD films 4332 to 4362 are stacked by physical vapor deposition.

  After the four external electrode terminals (first to fourth external electrode terminals 433 to 436) of this embodiment are joined to the quartz crystal diaphragm 2, as shown in FIG. The excitation electrodes (the first excitation electrode 221, the second excitation electrode 222, and the dotted line portion in FIG. 7) of the surfaces 211 and 212 are formed at positions where they do not overlap in plan view. According to this configuration, it is possible to reduce the adverse effect of stray capacitance and external noise generated in both the external terminal electrode and the excitation electrode.

  The four side surfaces 413 of the second sealing member 4 are connected to the external electrode terminals 433 to 436 as shown in FIGS. Four external electrode side terminals (first to fourth external electrode side terminals 441 to 444) in a region where the separation portion 421a of the sealing portion is formed and in a region where the four outer peripheral edge portions 421b of the sealing portion do not exist. ) Is provided.

  Further, in the four external electrode side terminals (first to fourth external electrode side terminals 441 to 444) of the present embodiment, the ridges 414 of the four corners of the second sealing member 4 among the side surfaces 413 of the second sealing member 4. It is formed in 417417, and more specifically, is formed over the two side surfaces 413 centering on the ridges 414 to 417 at the four corners. These four external electrode side terminals (first to fourth external electrode side terminals 441 to 444) are formed on the side surface 413 by physical vapor phase growth, and formed on the underlying PVD films 441 to 441, and the underlying PVD films 441 to 441. It consists of the electrode PVD films 4412 to 4444 which are deposited by physical vapor phase growth on 4441. The four external electrode side surface terminals (first to fourth external electrode side surface terminals 441 to 444) may be formed only on part of the side surface without including the corners of the four corners.

  In the second sealing member 4, as shown in FIGS. 1, 6 and 7, four through holes (second through twenty-fifth through holes 451 through 451, penetrating between the one main surface 411 and the other main surface 412. ) Is formed. The twenty-second through hole 451 is connected to the first external electrode terminal 433 and the eleventh through hole 271 of the quartz crystal plate 2. The twenty-third through hole 452 is connected to the second external electrode terminal 434 and the twelfth through hole 272 of the quartz crystal plate 2. The twenty-fourth through hole 453 is connected to the third external electrode terminal 435 and the thirteenth through hole 273 of the quartz crystal plate 2. The twenty-fifth through hole 454 is connected to the fourth external electrode terminal 436 and the fourteenth through hole 274 of the quartz crystal plate 2.

  In the second to twenty-fifth through holes 451 to 454, as shown in FIGS. 1, 6 and 7, through electrodes 71 for electrically connecting electrodes formed on one main surface 411 and the other main surface 412 are It forms along the inner wall surface of the 22nd-25th through holes 451-454 each. Then, the central portions of the second to twenty-fifth through holes 451 to 454 are hollow part penetrating parts 72 penetrating between the one main surface 411 and the other main surface 412. Connection bonding patterns 73 are formed on the outer circumferences of the second to twenty-fifth through holes 451 to 454, respectively. The connection bonding pattern 73 is provided on one main surface 411 of the second sealing member 4.

  The connection bonding pattern 73 has the same configuration as the sealing-side second bonding pattern 421, and can be formed by the same process as the sealing-side second bonding pattern 421. Specifically, the connection bonding pattern 73 is formed on the principal surface 411 of the second sealing member 4 by physical vapor deposition, and the physical vapor phase is formed on the underlying PVD film. It consists of an electrode PVD film grown and laminated.

  In the crystal oscillator 101, the second to twenty-fifth through holes 451 to 454 are formed outside the inner space 13 (outside the outer peripheral surface of the bonding material 11) in a plan view. More specifically, the 22nd to 25th through holes 451 to 454 are provided at the four corners of the second sealing member 4 in a plan view. The second to twenty-fifth through holes 451 to 454 are not electrically connected to the sealing-side second bonding pattern 421. In addition, the first to fourth external electrode terminals 433 to 436 are also not electrically connected to the sealing second bonding pattern 421.

  In the quartz crystal oscillator 101 including the quartz crystal plate 2, the first sealing member 3, and the second sealing member 4 described above, the quartz crystal plate 2 and the first seal are not separately used without using a dedicated bonding material such as an adhesive. The member 3 is diffusion-bonded in a state where the vibration-side first bonding pattern 251 and the sealing-side first bonding pattern 321 are superimposed, and the quartz crystal plate 2 and the second sealing member 4 are vibrated-side second bonding pattern 252 Then, diffusion bonding is performed in a state where the second sealing pattern 421 on the sealing side is overlapped, and the package 12 having a sandwich structure shown in FIG. 1 is manufactured. As a result, the internal space 13 of the package 12, that is, the accommodation space of the vibrating portion 23 is hermetically sealed.

  The vibration-side first bonding pattern 251 and the sealing-side first bonding pattern 321 themselves become the bonding material 11 generated after diffusion bonding, and the vibration-side second bonding pattern 252 and the sealing-side second bonding pattern 421 themselves diffuse. It becomes the bonding material 11 generated after bonding. The bonding material 11 is formed in an annular shape in a plan view, and the outer edge is formed in a substantially octagonal shape.

  At this time, diffusion bonding is performed in a state where the connection bonding patterns 73 of the outer periphery of each of the 11th to 25th through holes are also overlapped. Specifically, the connection bonding patterns 73 of the eleventh through hole 271 and the sixteenth through hole 351 are diffusion-bonded to each other. The bonding patterns 73 for connection of the eleventh through holes 271 and the twenty second through holes 451 are diffusion-bonded to each other. Further, the connection bonding patterns 73 of the twelfth through holes 272 and the seventeenth through holes 352 are diffusion-bonded to each other. The bonding patterns 73 for connection of the twelfth through holes 272 and the twenty third through holes 452 are diffusion-bonded to each other. Further, the connection bonding patterns 73 of the thirteenth through holes 273 and the eighteenth through holes 353 are diffusion-bonded to each other. The bonding patterns 73 for connection of the thirteenth through holes 273 and the twenty fourth through holes 453 are diffusion-bonded to each other. Further, the connection bonding patterns 73 of the fourteenth through holes 274 and the nineteenth through holes 354 are diffusion-bonded to each other. The bonding patterns 73 for connection of the fourteenth through holes 274 and the twenty fifth through holes 454 are diffusion-bonded to each other.

  Further, the connection bonding patterns 73 of the fifteenth through holes 275 and the twenty first through holes 356 are diffusion-bonded to each other. The connection bonding pattern 73 for connection of the fifteenth through hole 275 is diffusion bonded in a state of being superimposed on the connection bonding pattern 73 provided on the one main surface 411 of the second sealing member 4. The bonding pattern 73 for connection of the twentieth through hole 355 is diffusion bonded in a state of being overlapped with the bonding pattern 73 for connection extending from the first lead-out electrode 223 drawn from the first excitation electrode 221 of the quartz crystal plate 2. .

  Then, the respective connection bonding patterns 73 become the bonding material 14 generated after diffusion bonding. These bonding materials 14 formed by diffusion bonding serve to electrically connect the through electrodes 71 of the through holes, and play a role to hermetically seal the bonding portion. In FIG. 1, the bonding material 14 provided outside the bonding material 11 for sealing in a plan view is indicated by a solid line, and the bonding material 14 provided inside the bonding material 11 is indicated by a broken line. ing.

  The twentieth through hole 355 serves as a first electrical path (conductive path) for electrically connecting the IC 5 to the first excitation electrode 221. The twenty-first through holes 356 and the fifteenth through holes 275 form a second electrical path for conducting the IC 5 to the second excitation electrode 222. The sixteenth through holes 351, the eleventh through holes 271, and the twenty second through holes 451 form a third electrical path for electrically connecting the IC 5 to the first external electrode terminal 433. The seventeenth through holes 352, the twelfth through holes 272, and the twenty third through holes 452 form a fourth electrical path for electrically connecting the IC 5 to the second external electrode terminal 434. The eighteenth through holes 353, the thirteenth through holes 273, and the twenty-fourth through holes 453 form a fifth electrical path for electrically connecting the IC 5 to the third external electrode terminal 435. The nineteenth through holes 354, the fourteenth through holes 274, and the twenty-fifth through holes 454 form a sixth electrical path for electrically connecting the IC 5 to the fourth external electrode terminal 436.

  In the present embodiment, diffusion bonding is performed at normal temperature. The normal temperature as referred to herein means 5 ° C to 35 ° C. This normal temperature diffusion bonding has the following effects (gas generation suppression and bonding good), but this is a preferred example because it has a value lower than 183 ° C. which is the melting point of eutectic solder. However, only normal temperature diffusion bonding does not have an effect to be described below, and diffusion bonding may be performed at a temperature of normal temperature or more and less than 230 ° C. In particular, by diffusion bonding at a temperature of 200 ° C. or more and less than 230 ° C., it is less than 230 ° C., which is the melting point of Pb-free solder, and becomes more than the recrystallization temperature of Au (200 ° C.). The stability region can be stabilized. Further, in the present embodiment, since a dedicated bonding material such as Au-Sn is not used, no gas such as a plating gas, a binder gas or a metal gas is generated. Therefore, it can be made more than the recrystallization temperature of Au.

  Then, in the package 12 manufactured by diffusion bonding, the first sealing member 3 and the quartz crystal vibrating plate 2 have a gap of 1.00 μm or less, and the second sealing member 4 and the quartz crystal vibrating plate 2 are It has a gap of 1.00 μm or less. That is, the thickness of the bonding material 11 between the first sealing member 3 and the quartz crystal vibration plate 2 is 1.00 μm or less, and the bonding material 11 between the second sealing member 4 and the quartz crystal vibration plate 2 The thickness is 1.00 μm or less (specifically, 0.15 μm to 1.00 μm in the Au-Au junction of the present embodiment). In addition, in the conventional metal paste sealing material which used Sn as a comparison, it becomes 5 micrometers-20 micrometers.

  In the crystal oscillator 101, the first excitation electrode 221, the second excitation electrode 222, and the first to fourth external electrode terminals 433 to 436 form a bonding material 11 (a vibration side) as a sealing portion that hermetically seals the vibration portion 23. The first bonding pattern 251 and the sealing-side first bonding pattern 321, the vibration-side second bonding pattern 252, and the sealing-side second bonding pattern 421 are not electrically connected. In detail, the first excitation electrode 221 is electrically connected to the IC 5 via the first electric path (twentieth through hole 355) and the electrode pattern 33 in order. The second excitation electrode 222 is electrically connected to the IC 5 via the second electric path (the 15th through hole 275 and the 21st through hole 356) and the electrode pattern 33 in order. The first and second electrical paths are internal electrical paths disposed inward of the bonding material 11 in plan view. The fifteenth through holes 275 and the twenty first through holes 356 constituting the second electric path are provided so as not to overlap in a plan view.

  In addition, the IC 5 electrically connects the first external electrode terminal 433 to the electrode pattern 33 and the third electric path (the sixteenth through holes 351, the eleventh through holes 271, and the twenty second through holes 451) in this order. It is connected. The IC 5 is electrically connected to the second external electrode terminal 434 via the electrode pattern 33 and the fourth electric path (the 17th through hole 352, the 12th through hole 272, and the 23rd through hole 452) in this order. It is The IC 5 is electrically connected to the third external electrode terminal 435 via the electrode pattern 33 and the fifth electric path (the 18th through hole 353, the 13th through hole 273, and the 24th through hole 453 in this order). The IC 5 electrically connects the fourth external electrode terminal 436 to the electrode pattern 33 and the sixth electric path (the 19th through hole 354, the 14th through hole 274, and the 25th through hole 454 in this order). The third to sixth electrical paths are external electrical paths disposed outward of the bonding material 11 in plan view.

  The sixteenth through holes 351, the eleventh through holes 271, and the twenty-second through holes 451 that constitute the third electrical path are provided so as to overlap in a plan view. The seventeenth through holes 352, the twelfth through holes 272, and the twenty-third through holes 452 that constitute the fourth electrical path are provided so as to overlap in a plan view. The eighteenth through holes 353, the thirteenth through holes 273, and the twenty-fourth through holes 453 constituting the fifth electric path are provided so as to overlap in a plan view. The nineteenth through holes 354, the fourteenth through holes 274, and the twenty-fifth through holes 454 that constitute the sixth electric path are provided so as to overlap in a plan view. Thus, when the IC 5 is mounted on the one main surface 311 of the first sealing member 3 by the FCB method, it is possible to secure a wide region in which the FCB method can be performed.

  In the present embodiment, in the crystal oscillator 101, the bonding material 11 as the sealing portion is provided along the outer peripheral edge of the package 12 in a portion other than the four corners of the package 12 in a plan view. Hereinafter, this point will be described with reference to FIGS. 1 to 9. FIG. 9 is a view showing the positional relationship between the bonding material 11 in the quartz oscillator 101 and the vibrating portion 23 of the quartz crystal plate 2, the through hole, and the like in a plan view. In FIG. 9, as the through holes, the first to fifteenth through holes 271 to 275 of the quartz crystal plate 2 are representatively shown. In the present embodiment, the outer peripheral edge of the package 12 and the outer peripheral edges of the crystal vibrating plate 2, the first sealing member 3, and the second sealing member 4 coincide with each other in plan view.

  In the quartz crystal oscillator 101, the bonding material 11 is formed by diffusion bonding of the vibration-side first bonding pattern 251 and the sealing-side first bonding pattern 321 between the quartz crystal plate 2 and the first sealing member 3. The bonding material 11 is formed by diffusion bonding of the vibration-side second bonding pattern 252 and the sealing-side second bonding pattern 421 between the quartz crystal plate 2 and the second sealing member 4.

  The vibration-side first bonding pattern 251, the vibration-side second bonding pattern 252, the sealing-side first bonding pattern 321, and the sealing-side second bonding pattern 421 have the same shape and size in plan view. The bonding material 11 between the quartz crystal plate 2 and the first sealing member 3 and the bonding material 11 between the quartz crystal plate 2 and the second sealing member 4 have the same shape and size in plan view. It is formed. As described above, in the quartz crystal oscillator 101, the bonding material 11 having the same shape and size in plan view is formed on both main surfaces 211 and 212 of the quartz crystal plate 2, respectively.

  The outer edge of the bonding material 11 is octagonal in plan view. The outer edge shape of the bonding material 11 is the outer edge shape of the vibration-side first bonding pattern 251, the vibration-side second bonding pattern 252, the sealing-side first bonding pattern 321, and the sealing-side second bonding pattern 421 (FIGS. 6) has the same shape.

  In the crystal oscillator 101, the bonding material 11 is provided along (in parallel with) the outer peripheral edge of the package 12 at portions other than the four corners of the package 12 in a plan view. The bonding material 11 has third to sixth electric paths at four corners of the package 12 (that is, first to fourteenth through holes 271 to 274, sixteenth to nineteenth through holes 351 to 354, and second to twenty fifth through holes 451 to 454) are arranged. The bonding material 11 is provided to surround the vibrating portion 23 in plan view, and the housing space (internal space 13) of the vibrating portion 23 is hermetically sealed by the bonding material 11.

  Specifically, as shown in FIG. 9, in plan view, the bonding material 11 is provided with a pair of first straight portions 11A provided along (in parallel with) a pair of short sides of the package 12 and the package It is provided so as to connect a pair of second linear portions 11B provided along (in parallel with) a pair of long sides of 12 and an end portion of the first linear portion 11A and an end portion of the second linear portions 11B. And four connecting portions 11C. One pair of first straight portions 11A and one pair of second straight portions 11B form an outer peripheral edge along the outer peripheral edge (short side and long side) of the package 12, and the four connecting portions 11C are It is a separation part separated from the outer periphery of 12.

  The pair of first straight portions 11A are provided in proximity to the short side of the package 12 in plan view. The length (dimension in the short side direction) of the first straight portion 11A is at least [1/3] or more of the short side of the package 12. The lengths of the two first straight portions 11A are the same. Eleventh and twelfth through holes 271 and 272 are provided on both sides of one first linear portion 11A in the short side direction at predetermined intervals.

  The outer end of one of the first straight portions 11A is provided closer to the short side of the package 12 than the straight line L1 connecting the centers of the eleventh and twelfth through holes 271 and 272 in plan view. Thirteenth and fourteenth through holes 273 and 274 are provided on both sides in the short side direction of the other first linear portion 11A at predetermined intervals.

  The outer end of the other first straight portion 11A is provided closer to the short side of the package 12 than the straight line L2 connecting the centers of the thirteenth and fourteenth through holes 273 and 274 in plan view. In the present embodiment, the outer end of the first straight portion 11A is provided at a predetermined distance from the short side of the package 12. Further, the inner end of one of the first straight portions 11A is located on the straight line L1 in plan view, and the inner end of the other first straight portion 11A is located on the straight line L2 in plan view There is.

  If the outer end of one of the first straight portions 11A is closer to the short side of the package 12 than the straight line L1, the inner end of the first straight portion 11A may be located outside the straight line L1. It may be located inside the straight line L1 or good. Similarly, if the outer end of the other first straight portion 11A is closer to the short side of the package 12 than the straight line L2, the inner end of the first straight portion 11A is located outside the straight line L2. Or may be located inside the straight line L2.

  The pair of second straight portions 11B are provided in proximity to the long side of the package 12 in plan view. The length (the dimension in the long side direction) of the second straight portion 11B is at least [1/3] or more of the long side of the package 12, and is longer than the first straight portion 11A described above There is. The lengths of the two second straight portions 11B are the same.

  Eleventh and thirteenth through holes 271 and 273 are provided on both sides of one second linear portion 11B in the long side direction at predetermined intervals. The outer end of one second straight portion 11B is provided closer to the long side of the package 12 than the straight line L3 connecting the centers of the eleventh and thirteenth through holes 271 and 273 in plan view.

  Twelfth and fourteenth through holes 272 and 274 are provided on both sides in the long side direction of the other second linear portion 11B at predetermined intervals. The outer end of the other second straight portion 11B is provided closer to the long side of the package 12 than the straight line L4 connecting the centers of the twelfth and fourteenth through holes 272 and 274 in plan view. In the present embodiment, the outer end of the second straight portion 11B is provided at a predetermined distance from the long side of the package 12. Further, the inner end of one second linear portion 11B is located on the straight line L3 in plan view, and the inner end of the other second straight portion 11B is located on the straight line L4 in plan view There is.

  If the outer end of one of the second straight portions 11B is closer to the long side of the package 12 than the straight line L3, the inner end of the second straight portion 11B may be located outside the straight line L3. It may be or may be located inside the straight line L3. Similarly, if the outer end of the other second straight portion 11B is closer to the long side of the package 12 than the straight line L4, the inner end of the first straight portion 11B is located outside the straight line L4. Or may be located inside the straight line L4.

  The four connecting portions 11C are not provided in parallel to the outer peripheral edge (short side and long side) of the package 12 in plan view. In the present embodiment, the connecting portion 11C extends substantially in parallel to one of the two diagonal lines of the package 12. That is, the connecting portion 11C is provided to intersect the diagonal of the package 12 in plan view. The connecting portion 11C may be disposed to be orthogonal to the diagonal of the package 12 in a plan view.

  The length of the connecting portion 11C is shorter than the first linear portion 11A and the second linear portion 11B described above. The lengths of the four connecting portions 11C are the same. The connecting portions 11C are provided at the four corners of the package 12, and are provided in the vicinity of the first to fourteenth through holes 271 to 274. The connecting portion 11C is provided at a predetermined distance from the bonding material 14 (connection bonding pattern 73) on the outer periphery of the first to fourteenth through holes 271 to 274.

  As described above, in the present embodiment, the bonding material 11 is provided along the outer peripheral edge of the package 12 at portions other than the four corners of the package 12 in plan view, and the through holes (11th to Fourteen through holes 271 to 274, sixteenth to nineteenth through holes 351 to 354, and second to twenty-fifth through holes 451 to 454) are disposed outside the bonding material 11. Thereby, the following effects can be obtained.

  The space of the internal space 13 in which the vibrating portion 23 of the quartz crystal plate 2 is hermetically sealed can be made as large as possible, and the vibrating portion 23 with the largest possible configuration can be used. Thereby, the degree of freedom in design of the vibrating portion 23 can be improved, and the vibrating portion 23 of various characteristics can be designed.

  In addition, spaces at four corners of the package 12 can be used as arrangement spaces for the first to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and the second to twenty-fifth through holes 451 to 454, In addition, since spaces other than the four corners of the outer periphery of the package 12 can be used as a placement space for the bonding material 11, the space of the outer periphery including the four corners of the package 12 can be effectively used. Therefore, in the sandwich crystal oscillator 101, it is possible to easily cope with the miniaturization.

  Moreover, since the outer edge shape of the bonding material 11 is formed in an octagonal shape in plan view, the bonding material 11, the first to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and The second to twenty-fifth through holes 451 to 454 can be arranged more efficiently.

  Here, peeling of the four corners of the package 12 is likely to occur in each layer (the quartz crystal plate 2, the first sealing member 3, and the second sealing member 4) of the package 12 by an external force. However, in the present embodiment, the first to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and the second to 25th through holes 451 to 454 are disposed at the four corners of the package 12. By arranging the bonding material 11 by avoiding the four corners of the package 12, the bonding material 11 can be protected from peeling due to external force. Here, since the outer edge shape of the bonding material 11 is octagonal and the connecting portion 11C is provided to intersect the diagonal of the package 12, the connecting portion 11C transmits from the four corners of the package 12 toward the center. Stress can be relieved, and the bonding material 11 can be protected from peeling due to external force.

  Further, in the bonding material 11, the first and second straight portions 11A and 11B along the outer peripheral edge of the package 12 respectively have a package than the straight lines L1 to L4 connecting the centers of two through holes in plan view. It is provided close to the outer periphery of 12. Then, the bonding material 11 is disposed so as to avoid the first to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and the second to 25th through holes 451 to 454 of the four corners of the package 12. It is done. That is, the first to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and the second to twenty-fifth through holes 451 to 454 are disposed outward of the bonding material 11. As described above, by reducing the number of the through holes provided inward of the bonding material 11 as much as possible, the airtightness of the internal space 13 in which the vibrating portion 23 of the quartz crystal plate 2 is airtightly sealed can be improved.

  Furthermore, when the crystal oscillator 101 is bonded to an external circuit board using solder (fluid conductive bonding material), the solder is applied to the external electrode terminals (first to fourth external electrode terminals 433-436) through the 22nd to 25th components. Along the through holes 451 to 454, it climbs up to the through portions 72 of the 22nd to 25th through holes 451 to 454, and the through portions 72 of the 22nd to 25th through holes 451 to 454 are buried. At this time, there is a concern that the airtightness of the internal space 13 in which the vibrating portion 23 of the quartz crystal plate 2 is airtightly sealed may be reduced due to the erosion action of the solder crawling to the penetrating portion 72. However, according to the present embodiment, the eleventh to fourteenth through holes 271 to 274, the sixteenth to nineteenth through holes 351 to 354, and the second to twenty-fifth through holes 451 are more outward than the bonding material 11. Since ~ 454 is arranged, the influence of the erosive action of the solder on the airtightness deterioration of the internal space 13 can be suppressed.

  Here, the external electrode terminals (first to fourth external electrode terminals 433 to 436) are generally provided at four corner portions of the other main surface 412 of the second sealing member 4. Third to sixth electric paths (i.e., first to fourteenth through holes 271 to 274, sixteenth to nineteenth through holes 351 to 354, and second to twenty-fifth through holes 451 connecting the external electrode terminal and the IC 5 ̃454) are provided at the four corners of the package 12. Thus, the external electrode terminal and the IC 5 can be connected at the shortest distance via the third to sixth electrical paths, and noise can be suppressed. Further, since the third to sixth electric paths are isolated from the vibrating portion 23 by the bonding material 11, even when a signal including a harmonic component is supplied to the third to sixth electric paths from the external electrode terminal. And the influence of noise due to harmonic components can be suppressed.

  In addition, while the third to sixth electric paths are provided on the outer side of the bonding material 11, the first and second electric paths connecting the IC 5 and the excitation electrode (the first excitation electrode 221 and the second excitation electrode 222) are Since the bonding material 11 is provided inward, it is possible to suppress an increase in parasitic capacitance (floating capacitance) due to the third to sixth electric paths. In this case, the third to sixth electrical paths are provided at the four corners of the package 12 and are provided at positions away from the excitation electrode, which is advantageous for suppressing parasitic capacitance. In addition, since the bonding material 11 is not connected to the first and second electrical paths, the generation of parasitic capacitance due to the connection of the two can be suppressed, and a large amount of variable frequency of the piezoelectric vibration device can be secured.

Further, in the present embodiment, the four side surfaces 413 of the second sealing member 4 are connected to the external electrode terminals 433 to 436, and the second bonding pattern 421 on the sealing side of the side surfaces 413 (sealing portion Four external electrode side terminals (first to fourth external electrode side terminals 441 to 444) in the region where the four outer peripheral edge portions 421b of the sealing portion do not exist. It is done. Thereby, the following effects can be obtained.

When bonding to an external circuit board using solder (flowable conductive bonding material), solder (flowable conductive bonding material) is connected to the external electrode terminal (first to fourth external electrode terminals 433-436) to the external electrode side surface terminal It crawls up along (the 1st-4th exterior electrode side terminal 441-444). Therefore, not only surface bonding of only the external electrode terminals (first to fourth external electrode terminals 433 to 436) by solder (fluid conductive bonding material), but also external electrode side terminals (first to fourth external electrode side terminals) Since the fillet part which a solder protrudes is formed along 441-444, and joint area increases, joint strength can be raised.

In particular, in the present embodiment, the external electrode side surface terminals (first to fourth external electrode side surface terminals 441 to 444) are the ridges 414 to 4 of the four corners of the second sealing member 4 in the side surface 413 of the second sealing member 4. Since it is formed in 417, it can be countered by forming fillet portions of a solder (fluid conductive bonding material) with respect to four corners of the package to which stress is easily applied by an external force to enhance the bonding strength.

Furthermore, in the present embodiment, at the four corners of the package 12, third to sixth electrical paths connecting the electrode pattern 33 for mounting the IC 5 and the external electrode terminals (first to fourth external electrode terminals 433 to 436) Through holes (i.e., first to fourteenth through holes 271 to 274, sixteenth to nineteenth through holes 351 to 354, and second to twenty fifth through holes 451 to 454) are provided, and the through electrode 71 is formed. There is. For this reason, when using solder (flowable conductive bonding material) to bond to an external circuit board, solder (flowable conductive bonding material) is also applied to the through electrodes inside of each through hole as in the case of the external electrode side surface terminal described above. By creeping up, it is possible to form a creeping up portion of the solder (fluid conductive bonding material) not only in the plan view peripheral portion of the external terminal electrode but also in the vicinity of the center. As a result, by being sandwiched by the two raised portions in the vicinity of the outer terminal electrode and in the vicinity of the center, the bonding strength with the external circuit board can be further enhanced without increasing the surface bonding region by the outer terminal electrode.

  In addition, although glass is used for the 1st sealing member 3 and the 2nd sealing member 4 in this Embodiment, it is not limited to this, You may use quartz. In addition, the crystal plate 2, the first sealing member 3 and the second sealing member 4 may be made of AT-cut quartz. In this case, the thermal expansion coefficients of the quartz crystal plate 2, the first sealing member 3 and the second sealing member 4 are the same, and the quartz crystal plate 2, the first sealing member 3 and the second sealing member 4 It is possible to suppress the deformation of the package 12 due to the difference in thermal expansion, and to improve the airtightness of the internal space 13 in which the vibrating portion 23 of the quartz crystal plate 2 is hermetically sealed. In addition, distortion due to deformation of the package 12 is transmitted to the first excitation electrode 221 and the second excitation electrode 222 through the holding portion 213 and may become a factor of frequency fluctuation. Such frequency fluctuation can be suppressed by forming the sealing member 3 and the second sealing member 4 entirely of quartz.

  Further, in the present embodiment, quartz is used for the piezoelectric vibration plate, but the present invention is not limited to this, and any other material may be used as long as it is a piezoelectric material, such as lithium niobate and lithium tantalate It may be

  Further, in the present embodiment, Ti (or Cr) and Au are used as the bonding material 11, but the invention is not limited thereto, and the bonding material 11 may be made of, for example, Ni and Au. .

  Further, in the present embodiment, although the outer edge shape of the bonding material 11 is octagonal, it is not limited to this, and the outer edge shape of the bonding material 11 is, for example, an arbitrary pentagon or more such as pentagon or hexagon. It may be a polygon of Further, the outer edge shape of the bonding material 11 may be a shape including a curved portion without being limited to a polygon, and specifically, the shape of the connecting portion 11C described above may be a curved shape such as an arc shape, for example. Good.

  Further, in the present embodiment, the bonding material 11 is disposed at a predetermined distance from the outer peripheral edge of the package 12, but the bonding material 11 may be formed up to the outer peripheral edge of the package 12.

  Further, in the present embodiment, although the external electrode terminals are four terminals of the first external electrode terminal 433, the second external electrode terminal 434, the third external electrode terminal 435, and the fourth external electrode terminal 436, The external electrode terminals may be, for example, any number of terminals such as six terminals or eight terminals.

  Further, in the present embodiment, the case where the two holding portions 213 and 213 are provided on the quartz crystal plate 2 has been described, but as shown in FIG. 10, only one holding portion 213 is provided on the quartz crystal plate 2. It is good also as composition. In this configuration, it is possible to reduce the influence of the vibration leakage of the vibrating portion 23 and the influence of the external stress. About each number in a figure of a vibration part, the same number is attached about the same or similar part, and it omits about detailed explanation.

  The present invention can be practiced in other various forms without departing from the spirit, spirit or main features of the present invention. Therefore, the above-described embodiment is merely illustrative in every point and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not limited at all by the text of the specification. Furthermore, all variations and modifications that fall within the equivalent scope of the claims fall within the scope of the present invention.

  The present invention is applicable to a piezoelectric vibration device having a sandwich structure in which a first sealing member and a second sealing member are stacked and joined via a piezoelectric vibration plate.

101 crystal oscillator 11 bonding material (sealing part)
Reference Signs List 12 package 13 internal space 2 quartz crystal vibrating plate 221 first excitation electrode 222 second excitation electrode 23 vibrating portion 271 to 274 first to fourth through holes (external through holes)
3 1st sealing member 4 2nd sealing member 5 IC (external element)

Claims (2)

A piezoelectric vibrating plate having a first excitation electrode formed on one main surface of a substrate and a second excitation electrode formed on the other main surface of the substrate to be paired with the first excitation electrode;
A first sealing member covering the first excitation electrode of the piezoelectric diaphragm;
A second sealing member covering the second excitation electrode of the piezoelectric diaphragm;
The other principal surface of the first sealing member and one principal surface of the piezoelectric diaphragm are joined, and the one principal surface of the second sealing member and the other principal surface of the piezoelectric diaphragm are joined In the piezoelectric vibration device, an approximately rectangular parallelepiped package is formed, and the package is provided with an internal space in which the vibration portion of the piezoelectric vibration plate including the first excitation electrode and the second excitation electrode is hermetically sealed. ,
The sealing portion for hermetically sealing the vibrating portion of the piezoelectric diaphragm is formed in an annular shape in a plan view, and at the four corners of the package, separation portions separated from the outer peripheral edge, and portions other than the separation portions. And an outer peripheral edge provided along the outer peripheral edge of the package, and not electrically connected to the respective excitation electrodes,
At four corners of the other main surface of the second sealing member, a plurality of external electrode terminals electrically connected to the external circuit board are formed;
A piezoelectric vibration device characterized in that an external electrode side surface terminal is provided on a side surface of a second sealing member in a region connected to the external electrode terminal and in which a separation portion of the sealing portion is formed. In the piezoelectric vibration device according to claim 1,
The four corners of the package are provided with through holes penetrating between the one main surface and the other main surface of the piezoelectric vibration plate,
A plurality of wiring patterns are formed on one main surface of the first sealing member,
Each of the through holes is formed with a through electrode for electrically connecting a part of the plurality of wiring patterns and a part of the plurality of external electrode terminals. device.

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