Piezoelectric vibration device

Abstract

Provided is a laminated piezoelectric vibration device that has been miniaturized and has high wiring density, said device having high operational reliability as a result of the adoption of a structure that is unlikely to experience a malfunction due to the external environment or the like.　In a state in which an IC chip is bonded to the upper surface of a first sealing member 3, a cavity section that is located between a vibration unit of a piezoelectric vibration plate and a first sealing member 3 and second sealing member is disposed so as to overlap the undersides of a control function pad and a data wiring pad of the IC chip, and a control function wiring unit 39d and a data writing wiring unit 39g of the first sealing member 3 are formed to have floating island shapes that are not connected to any element.

Description

Piezoelectric Vibration Device

[0001] The present invention relates to a piezoelectric vibration device.

[0002] Conventionally, there has been a stacked piezoelectric vibration device that has a piezoelectric vibration plate that is rectangular in plan view, an upper sealing plate, and a lower sealing plate, the upper and lower surfaces of the piezoelectric vibration plate are covered by the upper sealing plate and the lower sealing plate, respectively, and are hermetically sealed to form a piezoelectric vibrator, and an integrated circuit element with a built-in oscillation amplifier is connected to the upper surface side of the upper sealing plate of the piezoelectric vibrator (see, for example, Patent Document 1).

[0003] Patent No. 6547825

[0004] In stacked piezoelectric devices, the device itself is smaller than that of ceramic package structures, and the wiring is also more closely packed. Therefore, external environments that generate strong electric or magnetic fields can have an electrical effect on the wiring, which can add unnecessary current and adversely affect the operation of the piezoelectric oscillator.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a stacked piezoelectric vibration device that is small in size and has high wiring density, and that has high operational reliability.

[0006] In order to achieve the above object, a piezoelectric vibration device according to the present invention has a piezoelectric vibration plate having a rectangular shape in a plan view, an upper sealing plate, and a lower sealing plate, the upper and lower surfaces of the piezoelectric vibration plate being covered and hermetically sealed by the upper sealing plate and the lower sealing plate, respectively, to form a piezoelectric vibrator, and an integrated circuit element having a built-in oscillation amplifier is connected to the upper surface side of the upper sealing plate of the piezoelectric vibrator, the piezoelectric vibration plate having a vibration portion on which a pair of excitation electrodes are formed, and an outer frame portion surrounding the vibration portion, and a gap portion is formed between the vibration portion and the upper sealing plate and the lower sealing plate, the upper sealing plate has an integrated circuit element connecting wiring portion formed on its upper surface and to which the integrated circuit element is electrically connected, the lower sealing plate has external power supply terminals, external earth terminals, and external output terminals formed on at least three of the four corners on its lower surface, and the integrated circuit element is connected to the connecting surface of the upper sealing plate with the integrated circuit element connecting wiring portion The integrated circuit element has at least an output pad, a power supply pad, an earth pad, a piezoelectric vibrator input pad, a piezoelectric vibrator output pad, and a control function pad or a data writing pad formed on the upper sealing plate, and the integrated circuit element connection wiring portion of the upper sealing plate has at least an output wiring portion connected to the output pad, a power supply wiring portion connected to the power supply pad, an earth wiring portion connected to the earth pad, a first piezoelectric vibrator wiring portion connected to the piezoelectric vibrator input pad, a second piezoelectric vibrator wiring portion connected to the piezoelectric vibrator output pad, and a control function wiring portion or a data writing wiring portion connected to the control function pad or the data writing pad, and the integrated circuit element is arranged below the control function pad and / or the data writing pad of the integrated circuit element so that the gap portion and / or the earth wiring portion overlap.

[0007] According to this configuration, the integrated circuit element is positioned below the control function pad and / or data writing pad of the integrated circuit element so that the gap between the vibrating part and the upper sealing plate and the lower sealing plate and the earth wiring part of the integrated circuit element connecting wiring part of the upper sealing plate overlap, or the gap overlaps, or the earth wiring part overlaps. Therefore, no voltage is applied to the control function pad or data writing pad of the integrated circuit element, and it is possible to prevent the control function from malfunctioning or unnecessary data from being written due to the influence of an external environment that generates a strong electric field or magnetic field.

[0008] In this case, the piezoelectric vibration plate may further include a holding portion that connects the outer peripheral wall of the vibration portion and the inner peripheral wall of the outer frame portion, and a cutout portion formed by cutting out the piezoelectric vibration plate in the plate thickness direction between the vibration portion and the outer frame portion.

[0009] The control function wiring portion and / or the data writing wiring portion of the upper sealing plate may be connected to the power supply wiring portion or the earth wiring portion.

[0010] According to this configuration, by connecting the control function wiring portion and / or the data writing wiring portion of the upper sealing plate to the power supply wiring portion of the integrated circuit element connecting wiring portion of the upper sealing plate, the control function wiring portion or the data writing wiring portion can be fixed to the power supply potential, or by connecting the control function wiring portion and / or the data writing wiring portion to the earth wiring portion of the integrated circuit element connecting wiring portion, the control function wiring portion and / or the data writing wiring portion can be fixed to the earth (ground) potential. Therefore, by fixing the control function pad or the data writing pad of the integrated circuit element to the power supply potential or the earth potential, it is possible to prevent the control function from malfunctioning or unnecessary data from being written due to the influence of the external environment, etc.

[0011] The control function wiring portion and / or the data writing wiring portion of the upper sealing plate may be formed as a floating island that is not connected to either of them.

[0012] According to this configuration, by forming the control function wiring portion and / or the data writing wiring portion of the upper sealing plate in a floating island shape, it is possible to arrange the essential wiring portion without increasing the wiring area, which is effective in miniaturizing the piezoelectric vibration device. Furthermore, by forming the control function wiring portion or the data writing wiring portion in a floating island shape, it is possible to improve the bonding strength, and when the connection of the integrated circuit element is performed by the FCB (Flip Chip Bonding) method, it is possible to disperse the stress caused by the increased number of bumps, thereby preventing cracks in the upper sealing plate.

[0013] The integrated circuit element may be disposed below the control function pad and / or the data writing pad of the integrated circuit element so that the gap and the cutout overlap each other.

[0014] According to this configuration, the gap between the vibration part and the upper sealing plate and the lower sealing plate overlaps with the underside of the control function pad and / or the data writing pad, and the cutout overlaps with the underside of the control function pad and / or the data writing pad, thereby reliably blocking the application of voltage to the control function pad or the data writing pad, thereby reliably preventing the control function from malfunctioning or unnecessary data from being written due to influences from the external environment, etc.

[0015] In addition, it is preferable that the width of the outer frame portion of the piezoelectric diaphragm at a portion corresponding to a short side of the rectangle of the piezoelectric diaphragm is greater than that at a portion corresponding to a long side.

[0016] With this configuration, a large effective area for wiring paths can be secured in the outer frame of the piezoelectric diaphragm, which is wider and stronger than the long sides, and high strength can be maintained even when through holes or notches are formed, thereby reducing the congestion of wiring that accompanies miniaturization.

[0017] According to the present invention, a piezoelectric vibration device with high operational reliability can be provided by adopting a structure that is less likely to malfunction due to external environments that generate strong electric or magnetic fields, in a stacked piezoelectric vibration device that is small and has a high wiring density.

[0018] 1 is a cross-sectional view showing a schematic configuration of a piezoelectric vibration device according to a first embodiment of the present invention. FIG. 1 is a schematic plan view of the first main surface side of a first sealing member (upper sealing plate) of the piezoelectric vibration device of FIG. 1. FIG. 2 is a schematic bottom view of the second main surface side of the first sealing member of the piezoelectric vibration device of FIG. 1. FIG. 3 is a schematic plan view of the first main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 1. FIG. 4 is a schematic bottom view of the second main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 1. FIG. 5 is a schematic plan view of the first main surface side of a second sealing member (lower sealing plate) of the piezoelectric vibration device of FIG. 1. FIG. 6 is a schematic bottom view of the second main surface side of the second sealing member of the piezoelectric vibration device of FIG. 1. FIG. 7 is a schematic bottom view of an integrated circuit element (IC chip) connected to the piezoelectric vibration device of FIG. 1. FIG. 8 is a schematic plan view of the first main surface side of the first sealing member (upper sealing plate) of a piezoelectric vibration device according to a second embodiment of the present invention. FIG. 9 is a schematic bottom view of the second main surface side of the first sealing member of the piezoelectric vibration device of FIG. 9. FIG. 10 is a schematic plan view of the first main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 9. FIG. 11 is a schematic bottom view of the second main surface side of the piezoelectric vibration plate of the piezoelectric vibration device of FIG. 9. 16 is a schematic plan view of the first main surface side of a second sealing member (lower sealing plate) of the piezoelectric vibrating device of Fig. 9. FIG. 17 is a schematic bottom view of the second main surface side of the second sealing member of the piezoelectric vibrating device of Fig. 9. FIG. 18 is a schematic bottom view of an integrated circuit element (IC chip) connected to the piezoelectric vibrating device of Fig. 9. FIG. 19 is a schematic plan view of the first main surface side of a first sealing member (upper sealing plate) of a piezoelectric vibrating device according to a third embodiment of the present invention. FIG. 19 is a schematic bottom view of an integrated circuit element (IC chip) connected to the piezoelectric vibrating device of Fig. 16. FIG. 19 is a schematic plan view of the first main surface side of a first sealing member (upper sealing plate) of a piezoelectric vibrating device according to a fourth embodiment of the present invention.

[0019] First Embodiment A piezoelectric vibration device according to a first embodiment of the present invention will be described in detail with reference to Figures 1 to 8. In the following first embodiment, a case will be described in which quartz crystal is used for the piezoelectric vibration plate. However, in the piezoelectric vibration device of the present invention, the material used for the piezoelectric vibration plate is not limited to quartz crystal as long as it generates piezoelectric vibrations.

[0020] As shown in FIG. 1 , the piezoelectric vibration device 101 according to the first embodiment includes a piezoelectric diaphragm 2, a first sealing member 3, and a second sealing member 4, each of which has a substantially rectangular shape in plan view, and an IC chip 5 connected to the first sealing member 3. In this piezoelectric vibration device 101, the piezoelectric diaphragm 2 is bonded to the first sealing member 3, and the piezoelectric diaphragm 2 is bonded to the second sealing member 4 to form a package 12, which serves as a piezoelectric vibrator with a substantially rectangular sandwich structure. The IC chip 5 is mounted on the main surface (top surface) of the first sealing member 3, opposite the surface bonded to the piezoelectric diaphragm 2. The IC chip 5 is a one-chip integrated circuit element that incorporates an oscillation amplifier and forms an oscillation circuit together with the piezoelectric diaphragm 2. Here, the first sealing member 3 and the second sealing member 4 correspond to the "upper sealing plate" and "lower sealing plate," respectively, and the IC chip 5 corresponds to the "integrated circuit element" in the present invention.

[0021] In the piezoelectric diaphragm 2, a first excitation electrode 221 is formed on one of the main surfaces, that is, a first main surface 211, and a second excitation electrode 222 is formed on the other main surface, that is, a second main surface 212. In the piezoelectric vibrating device 101, a first sealing member 3 and a second sealing member 4 are bonded to each of the two main surfaces (the first main surface 211 and the second main surface 212) of the piezoelectric diaphragm 2, thereby forming a cavity in the package 12, and a vibrating part 22 (see FIGS. 4 and 5 ) including the first excitation electrode 221 and the second excitation electrode 222 is hermetically sealed in the cavity.

[0022] The piezoelectric vibration device 101 according to the first embodiment has a package size of, for example, 1.0 × 0.8 mm, and is designed to be compact and low-profile. In addition, in order to achieve the compact size, the package 12 does not have castellations, but rather uses through-holes (described later) to achieve electrode conduction.

[0023] Next, the piezoelectric vibration plate 2, the first sealing member 3, and the second sealing member 4 of the piezoelectric vibration device 101 will be described with reference to Figures 1 to 7. Note that the description here focuses on the individual components that are not joined together and are configured as individual components.

[0024] As shown in Figures 4 and 5, the piezoelectric diaphragm 2 is a piezoelectric substrate made of quartz crystal, and a first main surface 211 and a second main surface 212 are formed as flat, smooth surfaces (mirror-finished). In the first embodiment, an AT-cut quartz crystal plate that performs thickness-shear vibration is used as the piezoelectric diaphragm 2. In the piezoelectric diaphragm 2 shown in Figures 4 and 5, the first and second main surfaces 211, 212 of the piezoelectric diaphragm 2 are in the XZ' plane.

[0025] In this XZ' plane, the direction parallel to the short side (short side) of the rectangular piezoelectric diaphragm 2 is the X-axis direction, and the direction parallel to the long side (long side) of the rectangular piezoelectric diaphragm 2 is the Z'-axis direction. Note that AT-cut is a processing technique in which an artificial quartz crystal is cut at an angle of 35°15' around the X-axis relative to the Z-axis, which are the three crystal axes of the artificial quartz crystal: the electrical axis (X-axis), the mechanical axis (Y-axis), and the optical axis (Z-axis). In an AT-cut quartz plate, the X-axis coincides with the crystal axis of the quartz crystal. The Y'-axis and Z'-axis coincide with the axes tilted 35°15' from the Y-axis and Z-axis, respectively, of the crystal axes of the quartz crystal. The Y'-axis and Z'-axis directions correspond to the cutting direction when cutting the AT-cut quartz crystal plate. Note that the piezoelectric diaphragm 2 is not limited to the AT-cut quartz crystal plate described above; an SC-cut quartz crystal plate can also be used, and a tuning fork-type vibrator can also be used.

[0026] The piezoelectric diaphragm 2 has a vibration portion 22 having a substantially rectangular shape in plan view, with a pair of excitation electrodes (first excitation electrode 221, second excitation electrode 222) formed on a first main surface 211 and a second main surface 212, respectively; an outer frame portion 23 having an inner peripheral wall that is rectangular in plan view and surrounds the outer peripheral wall of the vibration portion 22; a holding portion 24 that holds the vibration portion 22 by connecting the outer peripheral wall of the vibration portion 22 to the inner peripheral wall of the outer frame portion 23; and a cutout portion 25 formed by cutting out the piezoelectric diaphragm 2 in the plate thickness direction between the vibration portion 22 and the outer frame portion 23. In other words, the piezoelectric diaphragm 2 has a configuration in which the vibration portion 22, the outer frame portion 23, and the holding portion 24 are integrally provided. Here, the width of the outer frame portion 23 at a portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2 is formed larger than that of a portion corresponding to the long sides.

[0027] The holding portion 24 is provided at only one location between the vibrating portion 22 and the outer frame portion 23. Furthermore, the vibrating portion 22 and the holding portion 24 are formed thinner than the outer frame portion 23. Due to this difference in thickness between the outer frame portion 23 and the holding portion 24, the natural frequencies of the piezoelectric vibrations of the outer frame portion 23 and the holding portion 24 differ, thereby suppressing the propagation of vibrations excited in the vibrating portion 22. Furthermore, by joining the first sealing member 3 and the second sealing member 4 to the piezoelectric diaphragm 2, a gap is formed inside the inner circumferential wall of the outer frame portion 23 between the vibrating portion 22 and the first sealing member 3 and the second sealing member 4, and this gap is sealed. Alternatively, the outer frame 23 of the piezoelectric diaphragm 2 may be made thicker than the vibrating portion 22 and the holding portion 24, and the gap may be formed by joining the flat first and second sealing members 3 and 4. Alternatively, the outer frame 23 may be made the same thickness as the vibrating portion 22 and the holding portion 24, and the gap may be formed by forming recesses in the first and second sealing members 3 and 4 and joining them. Furthermore, the position where the holding portion 24 is formed is not limited to one, and it may be provided in two or more positions between the vibrating portion 22 and the outer frame 23.

[0028] The retaining portion 24 extends (protrudes) in the +Z' direction from only one corner of the vibrating portion 22, which is located in the +X direction and the +Z' direction, to the outer frame portion 23. In this way, the retaining portion 24 is provided at a corner of the outer peripheral edge of the vibrating portion 22, where the displacement of the piezoelectric vibration is relatively small. Therefore, compared to when the retaining portion 24 is provided at a portion other than the corner (the center of the side), leakage of the piezoelectric vibration to the outer frame portion 23 via the retaining portion 24 can be suppressed, and the vibrating portion 22 can be more efficiently piezoelectrically vibrated. Furthermore, compared to when the retaining portion 24 is provided at two or more locations, the stress acting on the vibrating portion 22 can be reduced, and the frequency shift of the piezoelectric vibration caused by such stress can be reduced, thereby improving the stability of the piezoelectric vibration.

[0029] The first excitation electrode 221 is provided on the first main surface 211 side of the vibrating section 22, and the second excitation electrode 222 is provided on the second main surface 212 side of the vibrating section 22. Lead wiring (first lead wiring 223, second lead wiring 224) for connecting these excitation electrodes to external electrode terminals is connected to the first excitation electrode 221 and the second excitation electrode 222. The first lead wiring 223 is led out from the first excitation electrode 221 and connected to a connection bonding pattern 27 formed on the outer frame section 23 via the holding section 24. The second lead wiring 224 is led out from the second excitation electrode 222 and connected to a connection bonding pattern 28 formed on the outer frame section 23 via the holding section 24. In this way, the first lead wiring 223 is formed on the first main surface 211 side of the holding section 24, and the second lead wiring 224 is formed on the second main surface 212 side of the holding section 24.

[0030] A vibration-side sealing portion for bonding the piezoelectric diaphragm 2 to the first sealing member 3 and the second sealing member 4 is provided on each of the first main surface 211 and the second main surface 212. A vibration-side first bonding pattern 251 for bonding to the first sealing member 3 is formed as the vibration-side sealing portion on the first main surface 211. A vibration-side second bonding pattern 252 for bonding to the second sealing member 4 is formed as the vibration-side sealing portion on the second main surface 212. The vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 are provided on the outer frame portion 23. These two bonding patterns 251, 252 are formed in a shape surrounded by a rectangular outer frame that is slightly smaller than the rectangular shape of the piezoelectric diaphragm 2 in plan view and an approximately annular inner frame in plan view. Here, the first excitation electrode 221 and the second excitation electrode 222 are not electrically connected to the vibration-side first bonding pattern 251 and the vibration-side second bonding pattern 252 .

[0031] 4 and 5, the piezoelectric diaphragm 2 has five through holes formed between the first main surface 211 and the second main surface 212. Specifically, the four first through holes 261 of the piezoelectric diaphragm 2 are provided in the four corner regions of the outer frame portion 23, respectively. The second through hole 262 is provided in the outer frame portion 23 on one side in the Z'-axis direction of the vibrating portion 22 (the +Z'-direction side in FIGS. 4 and 5). Around the three first through holes 261 except for the first through hole 261 on the +Z'-direction and +X-direction side, connection bonding patterns 254 are formed, each separated from the vibration-side first and second bonding patterns 251, 252 by a rectangular slit 253. Furthermore, the first through-hole 261 on the +Z' direction and +X direction side has a connection bonding pattern 256 formed therein, which is separated from the vibration-side first and second bonding patterns 251, 252 except for a portion by a substantially C-shaped slit 255, and this connection bonding pattern 256 is connected to the vibration-side first bonding pattern 251. Furthermore, around the second through-hole 262, a connection bonding pattern 257 is formed on the first main surface 211 side, and a connection bonding pattern 28 is formed on the second main surface 212 side.

[0032] In the first through hole 261 and the second through hole 262, a through electrode for achieving electrical continuity between the electrodes formed on the first main surface 211 and the second main surface 212 is formed along the inner wall surface of each through hole. In addition, the central portion of each of the first through hole 261 and the second through hole 262 forms a hollow through portion that penetrates between the first main surface 211 and the second main surface 212.

[0033] In the piezoelectric diaphragm 2, the first excitation electrode 221, the second excitation electrode 222, the first lead wiring 223, the second lead wiring 224, the vibration-side first bonding pattern 251, the vibration-side second bonding pattern 252, and the connection bonding patterns 254, 256, 257, 27, and 28 can be formed by the same process. Specifically, these can be formed from base films formed by physical vapor deposition on both main surfaces 211 and 212 of the piezoelectric diaphragm 2, and bonding films formed by physical vapor deposition on the base films. In the first embodiment, Ti (or Cr) is used for the base films, and Au is used for the bonding films.

[0034] 2 and 3, the first sealing member 3 is, for example, a rectangular parallelepiped substrate formed from a single piezoelectric substrate made of quartz, and the second main surface 312 (the lower surface that is bonded to the piezoelectric diaphragm 2) of this first sealing member 3 is formed as a flat, smooth surface (mirror-finished). Note that it is preferable to use an AT-cut quartz similar to that used for the piezoelectric diaphragm 2 for the first sealing member 3 in order to make the thermal expansion coefficients of both the members the same, but other quartz cut plates, piezoelectric substrates, glass substrates, etc. may also be used.

[0035] As shown in Fig. 2, six electrode patterns 37 and two floating island-shaped electrode patterns 38 are formed on the first main surface 311 (the upper surface on which the IC chip 5 is mounted) of the first sealing member 3, which does not face the piezoelectric diaphragm 2. Eight wiring sections used as integrated circuit element connecting wiring sections to which eight pads of the IC chip 5, which will be described later, are connected are formed on some of the six electrode patterns and the two floating island-shaped electrode patterns so as to be located on the periphery of a dashed rectangle R in Fig. 2, which corresponds to the outer shape of the gap on the piezoelectric diaphragm 2 side, i.e., the inner peripheral wall of the outer frame section 23. Note that Fig. 2 also shows, by dashed line, a rectangle Ra which corresponds to the outer peripheral wall of the vibrating section 22 of the piezoelectric diaphragm 2, and the area sandwiched between the rectangles R and Ra corresponds to the cutout section 25.

[0036] The six electrode patterns 37a to 37f as the electrode pattern 37 and the electrode patterns 38a and 38b as the floating island electrode pattern 38 are formed in the arrangement shown in Fig. 2. That is, the electrode pattern 37a is formed in a substantially U-shape at the corner in the A2-B1 direction, the electrode pattern 37b is formed in a substantially L-shape at the approximate center of one short side on the A2 side of the first sealing member 3, the electrode pattern 37c is formed extending in the A1 direction from the corner in the A2-B2 direction along the long side on the B2 side of the first sealing member 3, the electrode pattern 37d is formed in a substantially L-shape at the corner in the A1-B2 direction, the electrode pattern 37e is formed in a substantially L-shape and extends in the A2 direction from the approximate center of the other short side on the A1 side of the first sealing member 3, and the electrode pattern 37f is formed in a substantially U-shape at the corner in the A1-B1 direction. In addition, a rectangular electrode pattern 38a is formed in the shape of a floating island at the corner inside the rectangle R in the A2-B2 direction, and another rectangular electrode pattern 38b is formed in the shape of a floating island separated by a slit 38c at a position inside the rectangle R of the electrode pattern 37e along the long side on the A1 side.

[0037] Some of the eight electrode patterns 37a to 37f, namely, the floating island electrode patterns 38a and 38b, are provided at locations located inside a rectangle R indicated by a dashed line in Fig. 2. As will be described in detail later, as shown in Fig. 8, a power supply pad 51a, a piezoelectric vibrator output pad 51b, a piezoelectric vibrator input pad 51c, a control function pad 51d, a ground pad 51e, a second output pad 51f, a data writing pad 51g, and a first output pad 51h are provided on the connection surface (lower surface) of the IC chip 5 facing the first sealing member 3, and an integrated circuit element wiring portion to which these pads 51a to 51h are connected is provided inside the rectangle R of each electrode pattern.

[0038] That is, the first sealing member 3 has a power supply wiring section 39a connected to the power supply pads 51a of the IC chip 5 at a position inside the rectangle R of the electrode pattern 37a, a second piezoelectric vibrator wiring section 39b connected to the piezoelectric vibrator output pads 51b at a position inside the rectangle R of the electrode pattern 37e, a first piezoelectric vibrator wiring section 39c connected to the piezoelectric vibrator input pads 51c at a position inside the rectangle R of the electrode pattern 37b, and a control function wiring section 39d connected to the control function pads 51d at a position inside the rectangle R of the electrode pattern 38a. 2, there are provided a control function wiring portion 39d, a ground wiring portion 39e connected to a ground pad 51e at a position inside the rectangle R of the electrode pattern 37c, a second output wiring portion 39f connected to a second output pad 51f at a position inside the rectangle R of the electrode pattern 37d, a data write wiring portion 39g connected to a data write pad 51g at a position inside the rectangle R of the electrode pattern 38b, and a first output wiring portion 39h connected to a first output pad 51h at a position inside the rectangle R of the electrode pattern 37f. Note that the gap portion of the piezoelectric diaphragm 2 overlaps the lower sides of the control function wiring portion 39d and the data write wiring portion 39g inside the rectangle R, and the cutout portion 25 between the rectangle R and the rectangle Ra overlaps the lower side of the control function wiring portion 39d.

[0039] In this way, four of the eight wiring portions 39a to 39h are arranged along each of the long side R1 on the A2 side and the long side R2 on the A1 side (see FIG. 2) of the rectangle R. Note that the data write pad 51g of the IC chip 5 and the data write wiring portion 39g of the first sealing member 3 are not limited to data write and may be replaced with something other than data write.

[0040] These eight wiring portions 39a to 39h are then bonded to eight pads 51a to 51h of the IC chip 5 by FCB (Flip Chip Bonding) using metal bumps (for example, Au bumps) B (see FIG. 1).

[0041] As shown in FIGS. 2 and 3 , the first sealing member 3 has six through holes formed therein that are connected to the six electrode patterns 37a to 37f, respectively, and that penetrate between the first main surface 311 and the second main surface 312. Specifically, the third through holes 322 at the four corners are formed in the electrode patterns 37a, 37c, 37d, and 37f at the four corners of the first sealing member 3, respectively. The fourth through hole 323 and the fifth through hole 324 are formed in the two electrode patterns 37b and 37e other than the four corners in FIGS. 2 and 3 . The A1 and A2 directions in FIGS. 2, 3, 6, and 7 correspond to the −Z′ and +Z′ directions in FIGS. 4 and 5, respectively, and the B1 and B2 directions in FIGS. 2, 3, 6, and 7 correspond to the −X and +X directions in FIGS. 4 and 5, respectively.

[0042] In the third through hole 322 and the fourth and fifth through holes 323, 324, through electrodes for achieving electrical continuity between the electrodes formed on the first main surface 311 and the second main surface 312 are formed along the inner wall surfaces of the respective through holes. In addition, the central portions of the third through hole 322 and the fourth and fifth through holes 323, 324 form hollow through portions that penetrate between the first main surface 311 and the second main surface 312.

[0043] A sealing-side first bonding pattern 321 for bonding to the upper surface side of the piezoelectric diaphragm 2 is formed on the second main surface 312 of the first sealing member 3. Similar to the vibration-side first bonding pattern 251 of the piezoelectric diaphragm 2, this sealing-side first bonding pattern 321 is formed in a shape surrounded by a rectangular outer frame that is slightly smaller than the rectangle of the first sealing member 3 in plan view, and an approximately annular inner frame in plan view. The inner frame of the sealing-side first bonding pattern 321 is indicated by a dashed line in FIG. 2 .

[0044] Third through holes 322 are formed at the four corners of the second main surface 312 of the first sealing member 3 that overlap the sealing-side first bonding pattern 321, and connection bonding patterns 326 are formed around each of these four third through holes 322, excluding the corners in the A2-B2 direction, and are separated from the sealing-side first bonding pattern 321 by rectangular slits 325. Furthermore, the third through holes 322 at the corners in the A2-B2 direction are surrounded by approximately C-shaped slits 327, and connection bonding patterns 328 are formed that are connected to the sealing-side first bonding pattern 321.

[0045] A substantially circular connection bond pattern 351 is formed around the fourth through hole 323, and a substantially circular connection bond pattern 352 is formed around the fifth through hole 324. Furthermore, the connection bond pattern 352 is disposed on the A1 side of the first sealing member 3, and a substantially circular connection bond pattern 353 is formed on the A2 side of the first sealing member 3, and the connection bond pattern 352 and the connection bond pattern 353 are connected by the wiring pattern 33. Note that the connection bond pattern 353 is not connected to the connection bond pattern 351.

[0046] The third, fourth, and fifth through holes 322, 323, and 324 have through electrodes formed along the inner wall surfaces thereof to ensure electrical continuity between the electrodes formed on the first main surface 311 and the second main surface 312. The central portions of the third to fifth through holes 322 to 324 each form a hollow through portion that penetrates between the first main surface 311 and the second main surface 312.

[0047] In the first sealing member 3, the electrode patterns 37a to 37f, 38a, and 38b, the sealing-side first bonding pattern 321, the connection bonding patterns 326, 328, and 351 to 353, and the wiring pattern 33 can be formed by the same process. Specifically, these can be formed from an underlayer film formed by physical vapor deposition on the first and second main surfaces 311 and 312 of the first sealing member 3, and a bonding film formed by physical vapor deposition on the underlayer film. In this embodiment, Ti (or Cr) is used for the underlayer film, and Au is used for the bonding film.

[0048] 6 and 7, the second sealing member 4 is, for example, a rectangular parallelepiped substrate formed from a single piezoelectric substrate made of quartz, and the first main surface 411 (the upper surface that bonds to the piezoelectric diaphragm 2) of this second sealing member 4 is formed as a flat, smooth surface (mirror-finished). Note that it is preferable to use an AT-cut quartz similar to that of the piezoelectric diaphragm 2 for the second sealing member 4 so that the thermal expansion coefficients of the two can be made the same, but other quartz cut plates, piezoelectric substrates, glass substrates, etc. may also be used.

[0049] A sealing-side second bonding pattern 421 is formed on the first main surface 411 of this second sealing member 4 for bonding to the underside of the piezoelectric diaphragm 2. Like the vibration-side first and second bonding patterns 251 and 252 of the piezoelectric diaphragm 2 and the sealing-side first bonding pattern 321 of the first sealing member 3, the sealing-side second bonding pattern 421 is formed in a shape surrounded by a rectangular outer frame that is slightly smaller than the rectangle of the second sealing member 4 in plan view and an approximately annular inner frame in plan view.

[0050] Four rectangular external electrode terminals 43 for electrical connection to the outside are provided on the second main surface 412 (the outer lower surface that does not face the piezoelectric diaphragm 2) of the second sealing member 4. The external electrode terminals 43 are located at the four corners (corner portions) of the second sealing member 4. The four external electrode terminals 43 correspond to the "external power supply terminal," the "external earth terminal," and two "external output terminals" in the present invention, respectively.

[0051] A sixth through hole 44 is formed at each of the four corners of the second sealing member 4, and these sixth through holes 44 are formed at a position on the first main surface 411 that overlaps with the sealing-side second bonding pattern 421, and at a position on the second main surface 412 that overlaps with each of the four external electrode terminals 43.

[0052] 6, on the first main surface 411, connection bonding patterns 46 are formed around each of the four sixth through holes 44, excluding the corners in the A2-B2 direction, and are separated from the sealing-side second bonding pattern 421 by rectangular slits 45. In addition, the sixth through holes 44 at the corners in the A2-B2 direction are surrounded by approximately C-shaped slits 47, and connection bonding patterns 48 are formed therearound and connected to the sealing-side second bonding pattern 421.

[0053] In the sixth through holes 44, through electrodes for establishing electrical continuity between the electrodes formed on the first main surface 411 and the second main surface 412 are formed along the inner wall surfaces of the respective through holes. In addition, the central portions of the respective sixth through holes 44 form hollow through portions that penetrate between the first main surface 411 and the second main surface 412.

[0054] In the second sealing member 4, the external electrode terminal 43, the sealing-side second bonding pattern 421, and the connection bonding patterns 46, 48 can be formed by the same process. Specifically, these can be formed from an underlayer film formed by physical vapor deposition on the first and second main surfaces 411, 412 of the second sealing member 4, and a bonding film formed by physical vapor deposition on the underlayer film. In this embodiment, Ti (or Cr) is used for the underlayer film, and Au is used for the bonding film.

[0055] The IC chip 5 has a built-in oscillation amplifier with two phase-inverted outputs, and as shown in FIG. 1, is bonded to the upper surface of the first sealing member 3 by, for example, the FCB method using metal bumps B, thereby forming a differential output type piezoelectric vibrator.

[0056] Eight pads are formed on the underside of the IC chip 5 at positions facing the eight wiring portions 39a to 39h, respectively. Specifically, as shown in FIG. 8, eight pads are formed on the periphery of the underside of the IC chip 5 at positions facing the power supply wiring portion 39a, and ＤＤa power supply pad 51 a connected to the first piezoelectric vibrator wiring section 39 b, a piezoelectric vibrator output pad 51 b facing the second piezoelectric vibrator wiring section 39 b and connected to the output of the excitation electrode of the piezoelectric vibrator; a piezoelectric vibrator input pad 51 c facing the first piezoelectric vibrator wiring section 39 c and connected to the input of the excitation electrode of the piezoelectric vibrator; a control function pad 51 d facing the control function wiring section 39 d and connected to the enable output; an earth pad 51 e facing the earth wiring section 39 e and connected to the earth (ground); a second output pad 51 f facing the second output wiring section 39 f and connected to the second output of the piezoelectric vibrator; a data write pad 51 g facing the data write wiring section 39 g and used for data write; and a first output pad 51 h facing the first output wiring section 39 h and connected to the first output of the piezoelectric vibrator.

[0057] Each pad 51a-51h of the IC chip 5 is bonded and electrically connected to each wiring portion 39a-39h of the first sealing member 3 by, for example, the FCB method using metal bumps B (see FIG. 1). At this time, the control function wiring portion 39d and the data write wiring portion 39g are disposed inside a rectangle R representing the outline of the gap, as shown in FIG. 2, so that the gap of the piezoelectric diaphragm 2 overlaps the underside of the control function pad 51d connected to the control function wiring portion 39d and the data write pad 51g connected to the data write wiring portion 39g. Furthermore, because the cutout portion 25 between the rectangle R and the rectangle Ra of the control function wiring portion 39d is located, the cutout portion 25 also overlaps the underside of the control function pad 51d.

[0058] After the pads 51a-51h of the IC chip 5 are bonded and electrically connected to the wiring portions 39a-39h of the first sealing member 3 via metal bumps B, an underfill agent F, such as an epoxy resin, is filled to fill the gap between the bottom surface of the IC chip 5 and the top surface of the first sealing member 3 to prevent short circuits caused by minute foreign particles adhering to the active surface of the IC chip 5, as shown in FIG. 1 . This prevents short circuits between pads caused by minute foreign particles, especially in IC chips 5 with many pads. It also contributes to preventing short circuits between pads even when the IC chip 5 is made smaller and the distance between pads is shorter. As a result, the entry paths of minute foreign particles around the IC chip 5 are blocked, improving the reliability of the connections between the internal pads.

[0059] In the piezoelectric vibration device 101 including the piezoelectric diaphragm 2, first sealing member 3, and second sealing member 4, the piezoelectric diaphragm 2 and the first sealing member 3 are diffusion-bonded with the vibrating-side first bonding pattern 251 and the sealing-side first bonding pattern 321 overlapping each other, and the piezoelectric diaphragm 2 and the second sealing member 4 are diffusion-bonded with the vibrating-side second bonding pattern 252 and the sealing-side second bonding pattern 421 overlapping each other, thereby producing the sandwich-structured package 12 shown in FIG. 1 . This hermetically seals the accommodating space for the vibrating portion 22, which is the gap in the package 12. At this time, the above-mentioned connecting bonding patterns are also diffusion-bonded with each other overlapping each other.

[0060] By joining the connection bonding patterns together, electrical conduction is achieved between the first excitation electrode 221, the second excitation electrode 222, the IC chip 5, and the external electrode terminal 43 in the piezoelectric vibration device 101.

[0061] Specifically, the first excitation electrode 221 is connected to the IC chip 5 via the first escape wiring 223, the connection bonding pattern 27, the connection bonding pattern 351, the through electrode in the fourth through hole 323, and the electrode pattern 37b in this order. The second excitation electrode 222 is connected to the IC chip 5 via the second escape wiring 224, the connection bonding pattern 28, the through electrode in the second through hole 262, the bond between the connection bonding pattern 257 and the connection bonding pattern 353, the wiring pattern 33, the connection bonding pattern 352, the through electrode in the fifth through hole 324, and the electrode pattern 37e in this order.

[0062] In addition, the IC chip 5 is connected to the external electrode terminal 43 via the electrode patterns 37a, 37c, 37d, and 37f, the through electrode in the third through hole 322, the junction between the connection bonding patterns 326 and 328 and the connection bonding patterns 254 and 256, the through electrode in the first through hole 261, the junction between the connection bonding patterns 254 and 256 and the connection bonding patterns 46 and 48, and the through electrode in the sixth through hole 44, in that order.

[0063] When the IC chip 5 is bonded to the upper surface of the first sealing member 3, the gaps between the vibration portion 22 of the piezoelectric diaphragm 2 and the first sealing member 3 and second sealing member 4 overlap the undersides of the control function pads 51d and data write pads 51g of the IC chip 5. Furthermore, a cutout 25 also overlaps the underside of the control function pad 51d. The control function wiring portion 39d and data write wiring portion 39g of the first sealing member 3 are arranged on the floating island-like electrode patterns 38a and 38b that are not connected to either, and the gaps between the vibration portion 22 of the piezoelectric diaphragm 2 and the first sealing member 3 and second sealing member 4 overlap the underside of the control function pad 51d. Furthermore, the outer frame portion 23 of the piezoelectric diaphragm 2 is formed so that the width of the portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2 is larger than the width of the portion corresponding to the long sides.

[0064] According to the first embodiment, the gap between the vibration portion 22 of the piezoelectric diaphragm 2 and the first and second sealing members 3 and 4 overlaps the underside of the control function pad 51d and data writing pad 51g of the IC chip 5, and the cutout portion 25 also overlaps the underside of the control function pad 51d. Therefore, the control function pad 51d and data writing pad 51g of the IC chip 5 are not in a state where a voltage is applied, making it possible to prevent malfunction of any control function (enable function) and to prevent unnecessary data from being written.

[0065] Furthermore, since the control function wiring section 39d and the data writing wiring section 39g of the first sealing member 3 are provided on floating island-shaped electrode patterns 38a, 38b, it is possible to arrange the essential wiring sections without increasing the wiring area, which is very effective in miniaturizing the piezoelectric vibration device 101, and the bonding strength can be improved.When bonding is performed using the FCB method using metal bumps B, the stress caused by an increased number of bumps can be distributed, and cracking of the first sealing member 3 can be prevented.

[0066] Furthermore, because the width of the outer frame portion 23 of the piezoelectric diaphragm 2 in the portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2 is formed larger than the portion corresponding to the long sides, a wide effective area for wiring paths can be secured in the outer frame portion 23 of the piezoelectric diaphragm 2, which is wider than the long sides and stronger, and high strength can be maintained even when through holes, notches, etc. are formed, thereby mitigating the congestion of wiring that accompanies the miniaturization of the piezoelectric vibration device 101. Furthermore, because the pads 51 a to 51 h of the IC chip 5 can be bonded to the wiring portions 39 a to 39 h of the first sealing member 3 at positions close to the short sides of the outer frame portion 23 of the piezoelectric diaphragm 2, which is wider than the long sides and stronger, cracking of the first sealing member 3 due to pressure stress during bonding can be reliably prevented.

[0067] Furthermore, since the eight pads 51a to 51h of the IC chip 5 are formed on the peripheral edge, the stress caused by the pressure when bonding the IC chip 5 to the first sealing member 3, for example, by the FCB method using metal bumps B, can be effectively dispersed.

[0068] Furthermore, wiring portions 39a and 39h, and wiring portions 39d and 39e of the first sealing member 3 are formed parallel to the short side direction (A1-A2 direction) on each of the two short side sides of the rectangle R shown by the dashed line in FIG. 2, and pads 51a and 51h, and pads 51d and 51e of the IC chip 5 are formed. As a result, stress due to pressure during bonding can be distributed evenly at multiple linear positions in the short side direction of the rectangle R.

[0069] Furthermore, when the eight pads 51a to 51h are bonded to the wiring portions 39a to 39h by the FCB method using the metal bumps B, the stress caused by the pressure applied during bonding can be dispersed, preventing the stress from concentrating on a part of the first sealing member 3, thereby preventing cracks in the first sealing member 3 and poor bonding strength.

[0070] Furthermore, pads 51a, 51d, and 51h are arranged at the three corners of rectangular region R indicated by dashed lines in FIG. 2, pads 51b and 51c are arranged shifted in the B1 and B2 directions from the center of the long side of rectangular region R in the A2 direction, and pads 51f and 51g are arranged shifted sequentially in the B2 direction from the center of the long side of rectangular region R in the A1 direction, thereby making it possible to effectively distribute stress caused by pressure when bonding IC chip 5 to first sealing member 3 using metal bumps B.

[0071] Furthermore, no wiring portion or pad is located on line L connecting the centers of the two opposing long sides of rectangular region R (see FIG. 2 ) in a plan view inside the inner peripheral wall of outer frame portion 23 of piezoelectric diaphragm 2, including the mounting pads of IC chip 5. Therefore, when eight pads 51 a to 51 h are bonded to wiring portions 39 a to 39 h by the FCB method using metal bumps B, the metal bumps B are not bonded at positions on the line passing through the centers of the opposing long sides of the rectangle of IC chip 5, which is the lowest point of deflection due to pressure during bonding. Furthermore, stress during bonding can be dispersed to prevent stress from concentrating on a part of first sealing member 3, thereby preventing cracking of first sealing member 3 and suppressing weakening of the bonding strength of metal bumps B.

[0072] In the first embodiment described above, when the IC chip 5 is bonded to the upper surface of the first sealing member 3, the control function pads 51d and data writing pads 51g of the IC chip 5 are arranged so that the gaps between the vibration portion 22 of the piezoelectric diaphragm 2 and the first sealing member 3 and the second sealing member 4 overlap with the lower sides of the control function pads 51d and data writing pads 51g of the IC chip 5. Alternatively, the ground wiring portion 39e may overlap with the lower sides of the control function pads 51d and data writing pads 51g of the IC chip 5. Also, the gaps between the vibration portion 22 of the piezoelectric diaphragm 2 and the first sealing member 3 and the second sealing member 4 and / or the ground wiring portion 39e may overlap with the lower side of either the control function pads 51d or the data writing pads 51g. Also, the gaps and cutout portion 25 of the piezoelectric diaphragm 2 may overlap with the lower side of the data writing pad 51g, similar to the control function pads 51d.

[0073] Second Embodiment A piezoelectric vibration device according to a second embodiment of the present invention will be described in detail with reference to Figures 9 to 15. In the second embodiment, the main difference is the configuration of the piezoelectric vibration plate 2A from the piezoelectric vibration plate 2 of the first embodiment. The schematic configuration of the piezoelectric vibration device is the same as that of the piezoelectric vibration device 101 of the first embodiment shown in Figure 1, which shows a cross section of the piezoelectric vibration device 101, and includes a piezoelectric vibration plate 2A, a first sealing member 3A, a second sealing member 4A, and an IC chip 5A connected to the first sealing member 3A.

[0074] The piezoelectric diaphragm 2A is formed using an AT-cut quartz crystal plate, as in the first embodiment. As shown in Figures 11 and 12, a first excitation electrode 221A is formed on one of the principal surfaces, a first principal surface 211A, and a second excitation electrode 222A is formed on the other principal surface, a second principal surface 212A. In the piezoelectric vibration device of the second embodiment, a first sealing member 3A and a second sealing member 4A are bonded to the first principal surface 211A and the second principal surface 212A of the piezoelectric diaphragm 2A, respectively, to form a cavity similar to the package 12 shown in Figure 1, and a vibration part 22A including the first excitation electrode 221A and the second excitation electrode 222A is hermetically sealed in the cavity. Note that, as in the first embodiment, the piezoelectric diaphragm 2A is not limited to an AT-cut quartz crystal plate; an SC-cut quartz crystal plate may also be used, and a tuning fork-type vibrator may also be used.

[0075] As shown in Figures 11 and 12, the piezoelectric vibration plate 2A is configured to include a vibration part 22A having a generally rectangular shape in plan view, with a first excitation electrode 221A and a second excitation electrode 222A formed on a first main surface 211A and a second main surface 212A, respectively, an outer frame part 23A having an inner peripheral wall that is rectangular in plan view and surrounds the outer peripheral wall of the vibration part 22A, a holding part 24A that connects the outer peripheral wall of the vibration part 22A and the inner peripheral wall of the outer frame part 23A, and cutout parts 25Aa and 25Ab formed by cutting out the piezoelectric vibration plate 2A in the plate thickness direction between the vibration part 22A and the outer frame part 23A. Here, the vibrating portion 22A and the holding portion 24A are formed thinner than the outer frame portion 23A, and by bonding the first sealing member 3A and the second sealing member 4A to the piezoelectric diaphragm 2A, a gap is formed inside the inner circumferential wall of the outer frame portion 23A between the vibrating portion 22A and the first sealing member 3A and the second sealing member 4A. Note that recesses may be formed in the opposing surfaces of the first and second sealing members 3A and 4A that face the flat piezoelectric diaphragm 2A, and the gap may be formed by bonding the first and second sealing members 3A and 4A. Furthermore, as in the first embodiment, the width of the outer frame portion 23A in the portion corresponding to the short sides of the rectangular piezoelectric diaphragm 2A is formed larger than the portion corresponding to the long sides.

[0076] The inner peripheral wall of the outer frame portion 23A and the outer peripheral wall of the vibration portion 22A are both rectangular in plan view. Furthermore, the long side direction of the piezoelectric vibration plate 2A in plan view and the long side direction of the inner peripheral wall of the outer frame portion 23A in plan view are arranged perpendicular to each other. One retaining portion 24A is provided on each of the +X direction and −X direction sides of the vibration portion 22A, and is composed of a vibration retaining portion 24Aa on the vibration portion 22A side and an outer frame retaining portion 24Ab on the outer frame portion 23A side. The width of the portion of the outer frame portion 23A corresponding to the short side of the rectangle of the piezoelectric vibration plate 2A is larger than the portion corresponding to the long side. Details of the retaining portions 24A will be described later.

[0077] The first excitation electrode 221A is provided on the first main surface 211A side of the vibrating part 22A, and the second excitation electrode 222A is provided on the second main surface 212A side of the vibrating part 22A. Lead wiring (first lead wiring 223A, second lead wiring 224A) is connected to the first excitation electrode 221A and the second excitation electrode 222A to connect them to external electrode terminals, respectively.

[0078] 11, the first escape wiring 223A is extracted from the first excitation electrode 221A in the +X direction, and is connected to a circular connection junction pattern 27A formed on the +Z' direction side of the first main surface 211A of the outer frame portion 23A via a holding portion 24A provided on the +X direction side of the vibrating portion 22A. As shown in Fig. 12, the second escape wiring 224A is extracted from the second excitation electrode 222A in the -X direction, and is connected to a circular connection junction pattern 28A formed on the +Z' direction side of the second main surface 212A of the outer frame portion 23A via a holding portion 24A provided on the -X direction side of the vibrating portion 22A.

[0079] Furthermore, because the first escape wiring 223A and the second escape wiring 224A are escaped in different directions, the escape wirings are not arranged opposite each other across the vibrating part 22A in the vibrating part 22A, which eliminates unnecessary excitation by the escape wiring in the vibrating part 22A and improves the stability of the characteristics.

[0080] The retaining portion 24A has a pair of vibration retaining portions 24Aa along a first imaginary straight line L1 in a first direction (X-axis direction) passing through the center point C of the vibrating portion 22A in a planar view, and a pair of outer frame retaining portions 24Ab extending in a second direction (Z'-axis direction) different from the first direction and connecting each vibration retaining portion 24Aa to two points on the inner wall of the outer frame portion 23A, each vibration retaining portion 24Aa connecting the outer peripheral wall of the vibrating portion 22A to the outer frame retaining portion 24Ab, and the outer frame retaining portion 24Ab connecting the vibration retaining portion 24Aa to the inner wall of the outer frame portion 23A, and the outer frame retaining portions 24Ab are formed line-symmetrically with respect to the first imaginary straight line L1 and line-symmetrically with respect to a second imaginary straight line L2 along a second direction that is perpendicular to the first imaginary straight line L1 and passes through the center point C of the vibrating portion 22A in a planar view.

[0081] More specifically, holding portions 24A formed in a generally T-shape in plan view are provided on the +X side and the −X side of vibrating portion 22A, which is rectangular in plan view, and holding portions 24A are arranged symmetrically with respect to first imaginary line L1 and second imaginary line L2. That is, holding portion 24A is integrally formed with vibration holding portion 24Aa extending linearly from the outer peripheral wall of vibrating portion 22A along first imaginary line L1, and outer frame holding portion 24Ab extending linearly parallel to second imaginary line L2.

[0082] The vibration retaining portion 24Aa and the outer frame retaining portion 24Ab are connected in directions perpendicular to each other, with the vibration retaining portion 24Aa extending toward the outer frame retaining portion 24Ab, which is parallel to the long side direction of the rectangular inner peripheral wall of the outer frame portion 23A, and the outer frame retaining portion 24Ab extending toward two opposing inner peripheral walls of the outer frame portion 23A, which are parallel to both short sides of the rectangular inner peripheral wall of the outer frame portion 23A. One end of the vibration retaining portion 24Aa on the side of the center point C is connected to the center of the long side of the vibrating portion 22A in the Z'-axis direction, and the other end of the vibration retaining portion 24Aa is connected to the center of the outer frame retaining portion 24Ab. The outer frame retaining portions 24Ab are connected to the four corners of the rectangular inner peripheral wall of the outer frame portion 23A. One end of outer frame holding portion 24Ab in the +Z' direction is connected to one of the inner peripheral walls of outer frame portion 23A facing the +Z' direction, and the other end of outer frame holding portion 24Ab in the -Z' direction is connected to one of the inner peripheral walls of outer frame portion 23A facing the -Z' direction. The length of vibration holding portion 24Aa along the X-axis is shorter than the length of outer frame holding portion 24Ab along the Z'-axis, and the width of vibration holding portion 24Aa along the Z'-axis is wider than the width of outer frame holding portion 24Ab along the X-axis.

[0083] The retaining portion 24A having such a configuration divides the cutout portion formed between the outer peripheral wall of the vibrating portion 22A and the inner peripheral wall of the outer frame portion 23A into four portions in a plan view. Specifically, the cutout portion 25Aa is divided into two portions surrounded by the outer peripheral wall of the vibrating portion 22A, the inner peripheral wall of the outer frame portion 23A, and the vibration retaining portion 24Aa and outer frame retaining portion 24Ab of the retaining portion 24, each of which is formed in a substantially U-shape in a plan view. The cutout portion 25Ab is divided into two portions surrounded by the inner peripheral wall of the outer frame portion 23A and the outer frame retaining portion 24Ab of the retaining portion 24, each of which is formed in a straight line extending along the Z'-axis direction in a plan view. Furthermore, one end of a pair of vibration holding portions 24Aa is connected to each end of the vibration portion 22A in the X-axis direction, and both ends of two outer frame holding portions 24Ab extending in the Z'-axis direction are connected to four locations on the inner wall of the outer frame portion 23A, so that the effects of external stress, etc. can be suppressed and deflection in the thickness direction can be suppressed.

[0084] The first and second main surfaces 211A and 212A of the piezoelectric diaphragm 2A are provided with vibration-side sealing portions for bonding the piezoelectric diaphragm 2A to the first and second sealing members 3A and 4A, respectively. The vibration-side sealing portion on the first main surface 211A includes a vibration-side first bonding pattern 251A for bonding to the first sealing member 3A. The vibration-side sealing portion on the second main surface 212A includes a vibration-side second bonding pattern 252A for bonding to the second sealing member 4A. The vibration-side first bonding pattern 251A and the vibration-side second bonding pattern 252A are provided on the outer frame portion 23A. These two bonding patterns 251A and 252A are formed in a shape surrounded by a rectangular outer frame that is slightly smaller than the rectangular shape of the piezoelectric diaphragm 2A in plan view and a substantially annular inner frame in plan view. Here, the first excitation electrode 221A and the second excitation electrode 222A are not electrically connected to the vibration-side first bonding pattern 251A and the vibration-side second bonding pattern 252A.

[0085] 11 and 12, the piezoelectric diaphragm 2A has five through holes formed between the first main surface 211A and the second main surface 212A. Specifically, the four first through holes 261A of the piezoelectric diaphragm 2A are provided in the four corner regions of the outer frame portion 23A. The second through holes 262A are provided in a circular connection bonding pattern 29A formed on the first main surface 211A side, which is the opposite side to the connection bonding pattern 28A on the second main surface 212A side of the outer frame portion 23A.

[0086] A connecting bonding pattern 254A is formed around each of the three first through holes 261A, excluding the first through hole 261A in the +Z' direction and the +X direction, separated from the vibration-side first and second bonding patterns 251A and 252A by a rectangular slit 253A. A connecting bonding pattern 256A is formed around the first through hole 261A in the +Z' direction and the +X direction, separated from the vibration-side first and second bonding patterns 251A and 252A by a substantially C-shaped slit 255A, except for a portion thereof, and this connecting bonding pattern 256A is connected to the vibration-side first bonding pattern 251A. A connecting bonding pattern 29A is arranged on the first main surface 211A side around the second through hole 262A, and a circular connecting bonding pattern 28A is arranged on the second main surface 212A side.

[0087] In first through hole 261A and second through hole 262A, a through electrode for establishing electrical connection between electrodes formed on first main surface 211A and second main surface 212A is formed along the inner wall surface of each through hole. In addition, the central portion of each of first through hole 261A and second through hole 262A forms a hollow through portion that penetrates between first main surface 211A and second main surface 212A.

[0088] In the piezoelectric vibration plate 2A, the first excitation electrode 221A, the second excitation electrode 222A, the first outgoing wiring 223A, the second outgoing wiring 224A, the vibration side first bonding pattern 251A, the vibration side second bonding pattern 252A, and the connection bonding patterns 254A, 256A, 27A, 28A, and 29A can be formed by the same process, as in the first embodiment.

[0089] As shown in Figures 9 and 10, the first sealing member 3A has substantially the same configuration as the first sealing member 3 of the first embodiment, and eight electrode patterns are formed on the first main surface 311A ​​of the first sealing member 3A. Eight wiring portions used as integrated circuit element connection wiring portions to which eight pads of the IC chip 5A (described later) are connected are formed on parts of six of these eight electrode patterns and two floating island electrode patterns, and are located on the periphery of a rectangle R (a rectangular region elongated in the B1-B2 direction, shown by dashed lines in Figure 9) on the inner peripheral wall of the outer frame portion 23A. A rectangle Ra corresponding to the outer peripheral wall of the vibration portion 22A of the piezoelectric diaphragm 2A is also shown by dashed lines in Figure 9, and the area sandwiched between the rectangles R and Ra corresponds to the cutout portion 25A.

[0090] The six electrode patterns 37Aa to 37Af as the electrode pattern 37A and the electrode patterns 38Aa and 38Ab as the floating island electrode pattern 38A are formed in the arrangement shown in Fig. 9. That is, the electrode pattern 37Aa is formed in a substantially U-shape at a corner in the A2-B1 direction, the electrode pattern 37Ab is formed in a substantially L-shape at approximately the center of one short side on the A2 side of the first sealing member 3A, the electrode pattern 37Ac is formed extending in the A1 direction from a corner in the A2-B2 direction along the long side on the B2 side of the first sealing member 3A, the electrode pattern 37Ad is formed in a substantially L-shape at a corner in the A1-B2 direction, the electrode pattern 37Ae is formed in a substantially L-shape and extends in the A2 direction from approximately the center of the other short side on the A1 side of the first sealing member 3A, and the electrode pattern 37Af is formed in a substantially U-shape at a corner in the A1-B1 direction. In addition, a rectangular electrode pattern 38Aa is formed in the shape of a floating island at the corner inside the rectangle R in the A2-B2 direction, and another rectangular electrode pattern 38Ab is formed in the shape of a floating island separated by a slit 38Ac at a position inside the rectangle R of the electrode pattern 37Ae along the long side on the A1 side.

[0091] Some of the eight electrode patterns 37Aa to 37Af, i.e., the island-like electrode patterns 38Aa and 38Ab, are arranged inside a rectangle R indicated by a dashed line in Fig. 9. As shown in Fig. 15, the connection surface (lower surface) of the IC chip 5A facing the first sealing member 3A is provided with power supply pads 51Aa, piezoelectric vibrator output pads 51Ab, piezoelectric vibrator input pads 51Ac, control function pads 51Ad, earth pads 51Ae, second output pads 51Af, data writing pads 51Ag, and first output pads 51Ah, as will be described later.

[0092] The first sealing member 3A also includes a power supply wiring section 39Aa connected to the power supply pads 51Aa of the IC chip 5A at a position inside the rectangle R of the electrode pattern 37Aa, a second piezoelectric vibrator wiring section 39Ab connected to the piezoelectric vibrator output pads 51Ab at a position inside the rectangle R of the electrode pattern 37Ae, a first piezoelectric vibrator wiring section 39Ac connected to the piezoelectric vibrator input pads 51Ac at a position inside the rectangle R of the electrode pattern 37Ab, and a control function wiring section 39Ac connected to the control function pads 51Ad at a position inside the rectangle R of the electrode pattern 38Aa. There are provided wiring section 39Ad, earth wiring section 39Ae connected to earth pad 51Ae at a position inside rectangle R of electrode pattern 37Ac, second output wiring section 39Af connected to second output pad 51Af at a position inside rectangle R of electrode pattern 37Ad, data write wiring section 39Ag connected to data write pad 51Ag at a position of electrode pattern 38Ab inside rectangle R, and first output wiring section 39Ah connected to first output pad 51Ah at a position inside rectangle R of electrode pattern 37Af.

[0093] These wiring portions 39Aa to 39Ah are arranged along the long side R1 on the A2 side and the long side R2 on the A1 side (see FIG. 9) of the rectangle R. Note that the data write pad 51Ag of the IC chip 5A and the data write wiring portion 39Ag of the first sealing member 3A are not limited to data writing and may be replaced with something other than data writing.

[0094] Then, as in the first embodiment, these eight wiring portions 39Aa to 39Ah are bonded to eight pads 51Aa to 51Ah of the IC chip 5 by FCB (Flip Chip Bonding) using metal bumps (e.g., Au bumps) B (see FIG. 1).

[0095] 9 and 10, the first sealing member 3A has six through holes formed therein that are connected to the six electrode patterns 37Aa to 37Af, respectively, and that penetrate between the first main surface 311A ​​and the second main surface 312A. Specifically, third through holes 322A at the four corners are formed in the electrode patterns 37Aa, 37Ac, 37Ad, and 37Af at the four corners of the first sealing member 3A, respectively. Fourth through holes 323A and fifth through holes 324A are provided in the two electrode patterns 37Ab and 37Ae other than the four corners, respectively, as shown in FIGS.

[0096] In the third through hole 322A and the fourth and fifth through holes 323A, 324A, through electrodes for establishing electrical continuity between the electrodes formed on the first main surface 311A ​​and the second main surface 312A are formed along the inner wall surfaces of the respective through holes. In addition, the central portions of the third through hole 322A and the fourth and fifth through holes 323A, 324A each form a hollow through portion that penetrates between the first main surface 311A ​​and the second main surface 312A.

[0097] A first sealing-side bonding pattern 321A for bonding to the upper surface of the piezoelectric diaphragm 2A is formed on the second main surface 312A of the first sealing member 3A. Similar to the first vibration-side bonding pattern 251A of the piezoelectric diaphragm 2A, the first sealing-side bonding pattern 321A is surrounded by a rectangular outer frame that is slightly smaller than the rectangular shape of the first sealing member 3A in plan view and a substantially annular inner frame in plan view. The inner frame of the first sealing-side bonding pattern 321A is indicated by a dashed dotted line in FIG. 9 . The width of the first sealing-side bonding pattern 321A along both long sides of the rectangle of the first sealing member 3A in plan view and the width of the first sealing-side bonding pattern 321A along both short sides of the rectangle of the first sealing member 3A are smaller than those of the first sealing-side bonding pattern 321 of the first sealing member 3 in the first embodiment.

[0098] Third through holes 322A are formed at the four corners of the second main surface 312A of the first sealing member 3A that overlap with the sealing-side first bonding pattern 321A, and connecting bonding patterns 326A are formed around each of the four third through holes 322A except for the corners in the A2-B2 direction, and are separated from the sealing-side first bonding pattern 321A by rectangular slits 325A. Furthermore, the third through holes 322A at the corners in the A2-B2 direction are surrounded by approximately C-shaped slits 327A, and connecting bonding patterns 328A are formed therearound that are connected to the sealing-side first bonding pattern 321A.

[0099] A substantially circular connection bond pattern 351A is formed around the fourth through hole 323A, and a substantially circular connection bond pattern 352A is formed around the fifth through hole 324. Furthermore, the connection bond pattern 352A is disposed on the A1 side of the first sealing member 3A, and a substantially circular connection bond pattern 353A is formed on the A2 side of the first sealing member 3A, and the connection bond pattern 352A and the connection bond pattern 353A are connected by the wiring pattern 33A. Note that the connection bond pattern 353A is not connected to the connection bond pattern 351A.

[0100] The third, fourth, and fifth through holes 322A, 323A, and 324A have through electrodes formed along the inner wall surfaces thereof to establish electrical continuity between the electrodes formed on the first main surface 311A ​​and the second main surface 312A. The central portions of the third to fifth through holes 322A to 324A each form a hollow through portion that penetrates between the first main surface 311A ​​and the second main surface 312A.

[0101] In the first sealing member 3A, the electrode patterns 37Aa to 37Af, 38Aa, 38Ab, the sealing-side first bonding pattern 321A, the connection bonding patterns 326A, 328A, 351A to 353A, and the wiring pattern 33A can be formed in the same process, as in the first embodiment.

[0102] 13 and 14 , the second sealing member 4A has substantially the same configuration as the second sealing member 4 of the first embodiment, and a sealing-side second bonding pattern 421A for bonding to the underside of the piezoelectric diaphragm 2A is formed on a first main surface 411A of the second sealing member 4A. Like the vibration-side first bonding pattern 251A of the piezoelectric diaphragm 2 and the sealing-side first bonding pattern 321A of the first sealing member 3, the sealing-side second bonding pattern 421A is formed in a shape surrounded by a rectangular outer frame that is slightly smaller than the rectangle of the second sealing member 4A in plan view and an approximately annular inner frame in plan view.

[0103] 14, four rectangular external electrode terminals 43A for electrical connection to the outside are provided on the second main surface 412A of the second sealing member 4A. The external electrode terminals 43A are located at the four corners (corner portions) of the second sealing member 4A.

[0104] A sixth through hole 44A is formed at each of the four corners of the second sealing member 4A, and these sixth through holes 44A are formed at positions on the first main surface 411A that overlap the sealing-side second bonding pattern 421A, and are formed at positions on the second main surface 412A that overlap the four external electrode terminals 43A, respectively.

[0105] 13, on the first main surface 411A, a connection bonding pattern 46A is formed around each of the four sixth through holes 44A, excluding the corners in the A2-B2 direction, and the connection bonding pattern 46A is separated from the sealing-side second bonding pattern 421A by a rectangular slit 45A. Also, the sixth through hole 44A at the corner in the A2-B2 direction is surrounded by a substantially C-shaped slit 47A, and a connection bonding pattern 48A is formed therearound and connected to the sealing-side second bonding pattern 421A.

[0106] In the sixth through holes 44A, through electrodes for establishing electrical continuity between the electrodes formed on the first main surface 411A and the second main surface 412A are formed along the inner wall surfaces of the respective through holes. The central portions of the respective sixth through holes 44A form hollow through portions that penetrate between the first main surface 411A and the second main surface 412A.

[0107] In the second sealing member 4A, the external electrode terminal 43A, the sealing-side second bonding pattern 421A, and the connection bonding patterns 46A and 48A can be formed in the same process, as in the first embodiment.

[0108] As in the first embodiment, the IC chip 5A has a built-in oscillation amplifier having two phase-inverted outputs, and as shown in Figure 15, it is bonded to the upper surface of the first sealing member 3A by, for example, the FCB method using metal bumps to form a differential output type piezoelectric vibrator.

[0109] At the peripheral portion of the lower surface of the IC chip 5A, there are provided eight wiring portions 39Aa to 39Ah, each of which is opposite to the power supply wiring portion 39Aa. ＤＤ a power supply pad 51Aa connected to the first piezoelectric vibrator wiring section 39Ab, a piezoelectric vibrator output pad 51Ab facing the second piezoelectric vibrator wiring section 39Ab and connected to the output of the excitation electrode of the piezoelectric vibrator; a piezoelectric vibrator input pad 51Ac facing the first piezoelectric vibrator wiring section 39Ac and connected to the input of the excitation electrode of the piezoelectric vibrator; a control function pad 51Ad facing the control function wiring section 39Ad and connected to the enable output; an earth pad 51Ae facing the earth wiring section 39Ae and connected to the earth (ground); a second output pad 51Af facing the second output wiring section 39Af and connected to the second output of the piezoelectric vibrator; a data write pad 51Ag facing the data write wiring section 39Ag and used for data writing; and a first output pad 51Ah facing the first output wiring section 39Ah and connected to the first output of the piezoelectric vibrator. As in the first embodiment, the pads 51Aa to 51Ah of the IC chip 5 are bonded and electrically connected to the wiring portions 39Aa to 39Ah of the first sealing member 3 by, for example, the FCB method using metal bumps.

[0110] As in the first embodiment, when the IC chip 5A is bonded to the upper surface of the first sealing member 3A, the gaps between the vibrating portion 22A of the piezoelectric diaphragm 2A and the first and second sealing members 3A and 4A overlap the undersides of the control function pads 51Ad and data write pads 51Ag of the IC chip 5A. Furthermore, as shown in Fig. 9, the control function wiring portion 39Ad overlaps the cutout portion 25A between the rectangle R representing the inner circumferential wall of the outer frame portion 23A and the rectangle Ra representing the outer circumferential wall of the vibrating portion 22A, and the cutout portion 25A also overlaps the underside of the control function pads 51Ad bonded to the control function wiring portion 39Ad. The control function wiring portion 39Ad and the data write wiring portion 39Ag of the first sealing member 3A are provided on floating island-like electrode patterns 38Aa and 38Ab that are not connected to either. Furthermore, the outer frame portion 23A of the piezoelectric diaphragm 2A is formed so that the width of the portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2A is larger than the width of the portion corresponding to the long sides.

[0111] As in the first embodiment, the gap between the vibration portion 22A of the piezoelectric vibration plate 2A and the first and second sealing members 3A and 4A may be formed by forming the vibration portion 22A and the holding portion 2A4 of the piezoelectric vibration plate 2A thinner than the outer frame portion 23A and joining the flat first and second sealing members 3A and 4A together; alternatively, the outer frame portion 23A may be made the same thickness as the vibration portion 22A and the holding portion 24A, and forming recesses in the first and second sealing members 3A and 4A and joining them together to form the gap.

[0112] According to the second embodiment, even in a piezoelectric vibration device having a piezoelectric vibration plate 2A configured to hold the vibration portion 22A to the outer frame portion 23A at four points by the holding portion 24A, the same effect as in the first embodiment can be obtained.

[0113] Furthermore, because the structure holds the vibrating portion 22A at four corners of the inner peripheral wall of the outer frame portion 23A, miniaturization is not hindered while satisfying the acceleration sensitivity evaluation of the piezoelectric diaphragm 2A. Moreover, it is possible to provide a piezoelectric vibration device using a piezoelectric diaphragm 2A that has an excellent overall balance of holding structure that can ensure an effective planar view area of ​​the vibrating portion 22A and is resistant to the effects of external stress and vibration leakage.

[0114] Furthermore, since both ends of the outer frame holding portions 24Ab of the two holding portions 24A are connected to the wider sides of the outer frame portion 23A, it is advantageous for ensuring strength against external shocks. Furthermore, since the outer frame holding portions 24Ab are connected to the four corners of the rectangular inner peripheral wall of the outer frame portion 23A, bending and stress of the outer frame portion 23A due to external shocks are easily alleviated, which is advantageous for stress alleviation.

[0115] In addition, because one end of vibration holding portion 24Aa of holding portion 24A is connected to the center of the opposing short side of vibrating portion 22A, it is possible to effectively suppress deflection of vibrating portion 22A with few connecting points. Furthermore, because the other end of vibration holding portion 24Aa of holding portion 24A is connected to the center of outer frame holding portion 24Ab, it is possible to easily maintain the balance of holding portion 24A and effectively suppress deflection of vibrating portion 22A.

[0116] In the second embodiment, the electrode pattern 38Aa on the top surface of the first sealing member 3A may be connected to the electrode pattern 37Ac, thereby electrically connecting the control function wiring portion 39Ad located on the electrode pattern 38Aa to the earth wiring portion 39Ae located on the electrode pattern 37Ac, or electrically connecting the control function wiring portion 39Ad to the power supply wiring portion 39Aa located on the electrode pattern 37Aa. Also, the data write wiring portion 39Ag located on the electrode pattern 38Ab of the first sealing member 3A may be connected to the power supply wiring portion 39Aa or the earth wiring portion 39Ae.

[0117] A piezoelectric vibration device according to a third embodiment of the present invention will be described in detail with reference to Figures 16 and 17. The piezoelectric vibration device of the third embodiment is a single-output device rather than a differential type, and the arrangement of some of the electrode patterns of the first sealing member 3B is different from that of the first embodiment. Below, differences from the first embodiment will be mainly described with reference to Figures 1 to 8, which show the piezoelectric vibration device 101 of the first embodiment. Note that in Figures 16 and 17, the same reference numerals as those in Figures 1 to 8 indicate the same or corresponding parts.

[0118] The first sealing member (upper sealing plate) 3B in the third embodiment differs from the first embodiment in the following respects: In the third embodiment, as shown in Fig. 16, an electrode pattern 37Ba is formed in a substantially U-shape at a corner in the A2-B1 direction, an electrode pattern 37Bb is formed in a substantially T-shape at the substantially center of one short side on the A2 side of the first sealing member 3, and an electrode pattern 37Bc is formed extending in a substantially linear manner along the long side on the B2 side of the first sealing member 3 from the corner in the A2-B2 direction to the corner in the B2-A1 direction. An electrode pattern 37Bd is formed in an approximately T-shape at approximately the center of the other short side on the A1 side of the first sealing member 3, and an electrode pattern 37Be is formed in an approximately U-shape at the corner in the A1-B1 direction. A third through hole 322B is formed at each of the four corner positions of the first sealing member 3B in the electrode patterns 37Ba, 37Bb, and 37Be, and fourth and fifth through holes 323B and 324B are formed in the electrode patterns 37Bb and 37Bd, respectively.

[0119] A second difference from the first embodiment is that the electrode patterns 37Ba to 37Be of the first sealing member 3B are provided with a power supply wiring section 39Ba, a first piezoelectric vibrator wiring section 39Bb, a control function wiring section 39Bc, an earth wiring section 39Bd, a second piezoelectric vibrator wiring section 39Be, and an output wiring section 39Bf, respectively.

[0120] 16 , the power supply wiring section 39Ba, the first piezoelectric vibrator wiring section 39Bb, the second piezoelectric vibrator wiring section 39Be, and the output wiring section 39Bf are arranged inside a rectangle R corresponding to the outer shape of the inner peripheral wall of the outer frame section 23 of the piezoelectric diaphragm 2, while the control function wiring section 39Bc and the ground wiring section 39Bd provided on the electrode pattern 37Bc are arranged outside the rectangle R and overlap the sealing-side first bonding pattern 321 (see FIG. 3 ) of the first sealing member 3B, which is indicated by a dashed line in FIG. 16 . Here, in the third embodiment, one of the two output external terminals of the second sealing member 4 is connected to the ground external terminal by the electrode pattern 37Bc. Therefore, the control function wiring section 39Bc and the ground wiring section 39Bd are maintained at ground potential.

[0121] Also, as shown in Figure 17, the peripheral portion of the underside of the IC chip 5B is provided with power supply pads 51Ba connected to the power supply wiring section 39Ba, piezoelectric vibrator input pads 51Bb connected to the first piezoelectric vibrator wiring section 39Bb, control function pads 51Bc connected to the control function wiring section 39Bc, earth pads 51Bd connected to the earth wiring section 39Bd, piezoelectric vibrator output pads 51Be connected to the second piezoelectric vibrator wiring section 39Be, and output pads 51Bf connected to the output wiring section 39Bf, and the arrangement of each pad 51Ba to 51Bf of the IC chip 5B is also different from that of the first embodiment.

[0122] In the third embodiment, as in the first embodiment, when the IC chip 5B is bonded to the upper surface of the first sealing member 3B, the control function wiring portion 39Bc and the grounding wiring portion 39Bd overlap the undersides of the control function pads 51Bc and the grounding pads 51Bd of the IC chip 5B, respectively. However, since the control function wiring portion 39Bc and the grounding wiring portion 39Bd are provided on a single electrode pattern 37Bc, the undersides of the control function pads 51Bc and the grounding pads 51Bd are overlapped by the grounding wiring portion 39Bd and are held at ground potential, and no voltage is applied to the control function pad 51d. Also, in the third embodiment, as in the first embodiment, the outer frame portion 23 of the piezoelectric diaphragm 2 is formed so that the width of the portion corresponding to the short sides of the rectangle of the piezoelectric diaphragm 2 is larger than the portion corresponding to the long sides.

[0123] Therefore, according to the third embodiment, even if the piezoelectric vibration device has only one output, the same effect as the first embodiment can be achieved, that is, it is possible to prevent any control function (enable function) from malfunctioning.

[0124] The present invention is not limited to the above-described configuration, and various design modifications can be made within the scope of the claims.

[0125] For example, in the first embodiment described above, when the IC chip 5 is bonded to the upper surface of the first sealing member 3, the gap between the vibration portion 22 of the piezoelectric diaphragm 2 and the first and second sealing members 3 and 4 overlaps the control function pads 51d and data writing pads 51g of the IC chip 5, and the cutout portion 25 also overlaps the lower side of the control function pad 51d. However, as a fourth embodiment, as shown in FIG. 18, the control function wiring portion 39d to which the control function pad 51d is connected may be arranged so as to overlap the gap inside the rectangle R, the cutout portion 25 between the rectangle R and the rectangle Ra (see FIGS. 4 and 5), and the sealing-side first bonding pattern 321, and the earth wiring portion 39e may overlap the lower side of the control function pad 51d via the sealing-side first bonding pattern 321 shown by the dotted line in FIG.

[0126] In addition, in the first and second embodiments described above, the control function wiring portions 39d, 39Ad and the data write wiring portions 39g, 39Ag of the first sealing member 3, 3A are provided on floating island-like electrode patterns 38a, 38Aa, 38b, 38Ab that are not connected to anything, and in the third embodiment, a case has been described in which only the data write wiring portion 39g of the first sealing member 3 is provided on the floating island-like electrode pattern 38b that is not connected to anything, but it is also possible to provide only the control function wiring portions 39d, 39Ad of the first sealing member 3, 3A on a floating island-like electrode pattern that is not connected to anything.

[0127] Furthermore, the piezoelectric diaphragms 2 and 2A in the above-described embodiments are not limited to AT-cut quartz crystal plates, but may also be SC-cut quartz crystal plates or tuning fork-type vibrators.

[0128] In the above-described embodiment, the electronic component element is an IC chip 5, 5A, which is an oscillator circuit element. The IC chip can be a CMOS output oscillation IC, a differential output oscillation IC, a VCXO IC, a TCXO IC, or the like.

[0129] In addition, in the first embodiment described above, an example was given of a through electrode formed inside a through hole as a conductive path from the IC chip 5 to the external electrode terminal 43 of the second sealing member 4, but it is also possible to use a so-called castellation as a conductive path, in which a recess such as a notch is formed on the external end surface of the piezoelectric vibration device (first sealing member, piezoelectric vibration plate, second sealing member) 101 and a side end electrode is formed on the surface of the recess.

[0130] Furthermore, the shapes of the first and second excitation electrodes 221 and 222 are not limited to the rectangular shapes shown in FIGS. 4 and 5, but may be circular or polygonal.

[0131] The present invention can be widely applied to piezoelectric vibration devices that have a piezoelectric vibration plate that is rectangular in plan view, an upper sealing plate, and a lower sealing plate, the upper and lower surfaces of the piezoelectric vibration plate are covered and hermetically sealed by the upper sealing plate and the lower sealing plate, respectively, to form a piezoelectric vibrator, and an integrated circuit element with a built-in oscillation amplifier is connected to the upper surface side of the upper sealing plate of the piezoelectric vibrator.

[0132] DESCRIPTION OF SYMBOLS 2, 2A ... Piezoelectric diaphragm 3, 3A, 3B ... First sealing member (upper sealing plate) 4, 4A ... Second sealing member (lower sealing plate) 5, 5A, 5B ... IC chip (integrated circuit element) 22, 22A ... Vibration section 23, 23A ... Outer frame section 24, 24A ... Holding section 25, 25A ... Cutout section 37a to 37f, 37Aa to 37Af, 37Ba to 37Be ... Electrode patterns 38a, 38b, 38Aa, 38Ab ... (Island-shaped) electrode patterns 39a to 39h, 39Aa to 39Ah, 39Ba to 39Bf ... Wiring section 51a to 51h, 51Aa to 51Ah, 51Ba to 51Bf ... Pads

Claims

1. A piezoelectric vibration device having a piezoelectric diaphragm having a rectangular shape in a plan view, an upper sealing plate, and a lower sealing plate, the upper and lower surfaces of the piezoelectric diaphragm being covered and hermetically sealed by the upper sealing plate and the lower sealing plate, respectively, to form a piezoelectric vibrator, and an integrated circuit element having a built-in oscillation amplifier is connected to the upper surface side of the upper sealing plate of the piezoelectric vibrator, wherein the piezoelectric diaphragm has a vibrating portion on which a pair of excitation electrodes are formed, and an outer frame portion surrounding the vibrating portion, and there is a gap between the vibrating portion and the upper and lower sealing plates, the upper sealing plate has an integrated circuit element connecting wiring portion formed on its upper surface and to which the integrated circuit element is electrically connected, and the lower sealing plate has an external power supply terminal, an external earth terminal, and an external output terminal formed on at least three of the four corners of its lower surface, and the integrated circuit element a piezoelectric vibrator device comprising: an output pad, a power supply pad, an earth pad, a piezoelectric vibrator input pad, a piezoelectric vibrator output pad, and a control function pad or a data writing pad formed on the connection surface of the upper sealing plate with the integrated circuit element connection wiring portion; wherein the integrated circuit element connection wiring portion of the upper sealing plate comprises at least: an output wiring portion connected to the output pad, a power supply wiring portion connected to the power supply pad, an earth wiring portion connected to the earth pad, a first piezoelectric vibrator wiring portion connected to the piezoelectric vibrator input pad, a second piezoelectric vibrator wiring portion connected to the piezoelectric vibrator output pad, and a control function wiring portion or a data writing wiring portion connected to the control function pad or the data writing pad; and wherein the integrated circuit element is arranged below the control function pad and / or the data writing pad of the integrated circuit element so that the gap and / or the earth wiring portion overlap.

2. The piezoelectric vibration device of claim 1, characterized in that the piezoelectric vibration plate further comprises a holding portion that connects the outer peripheral wall of the vibration portion and the inner peripheral wall of the outer frame portion, and a cutout portion formed by cutting out the piezoelectric vibration plate in the plate thickness direction between the vibration portion and the outer frame portion.

3. A piezoelectric vibration device as described in claim 1 or claim 2, characterized in that the control function wiring portion and / or the data writing wiring portion of the upper sealing plate are connected to the power supply wiring portion and / or the earth wiring portion.

4. A piezoelectric vibration device as described in claim 1 or claim 2, characterized in that the control function wiring portion and / or the data writing wiring portion of the upper sealing plate are formed in the form of a floating island that is not connected to either.

5. A piezoelectric vibration device as described in claim 2, characterized in that the integrated circuit element is positioned so that the gap portion overlaps the underside of the control function pad and / or the data writing pad of the integrated circuit element and the cutout portion overlaps the underside of the integrated circuit element.

6. A piezoelectric vibration device as described in any one of claims 1 to 4 dependent on claim 1, characterized in that the width of the outer frame portion of the piezoelectric vibration plate, which corresponds to the short side of the rectangle of the piezoelectric vibration plate, is larger than the width of the portion corresponding to the long side.

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