Piezoelectric Vibration Device

Abstract

Provided is a piezoelectric oscillation device that can firmly join to an external substrate at a location as close to the external substrate as possible. Provided is a piezoelectric oscillation device 1 in which at least an oscillator 2 and an integrated circuit element 10 having an oscillation-generating circuit are mounted on a substrate 11 having a wiring pattern that includes a plurality of pads on a first mounting surface 11a, which is one main surface of a pair of main surfaces, the substrate 11 also having an external connection terminal 11d that is electrically connected to a wiring pattern on a second mounting surface 11b, which is the other main surface parallel to the one main surface, and that is electrically connected to an external substrate P. The substrate 11 has a recess 11g in the second mounting surface 11b. The external connection terminal 11d is located within the recess 11g and a gap G is provided between the outer edges of the external connection terminal 11d and the side surfaces 11i of the recess 11g.

Description

[Technical Field]

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

[0002] Piezoelectric vibration devices include, for example, quartz crystal resonators that use quartz crystal resonators. The quartz crystal resonators include a quartz crystal resonator, which is a piezoelectric element, a holding member that holds the quartz crystal resonator, and a lid member that seals the holding member. The quartz crystal resonator is held in the box-shaped holding member made of an insulator such as ceramic. In the quartz crystal resonator, the quartz crystal resonator is sealed within the holding member by a lid member with the electrodes of the quartz crystal resonator and the electrodes of the holding member bonded together.

[0003] In such a piezoelectric vibrator device, the box-shaped holding member and the lid member are stacked on top of each other, which increases the thickness of the piezoelectric vibrator device. Therefore, a piezoelectric vibrator is known in which a piezoelectric diaphragm having a vibrating portion with a first excitation electrode and a second excitation electrode, and an outer frame portion connected to the vibrating portion via a connecting portion and surrounding the vibrating portion is sealed with a sealing member. This laminated piezoelectric vibrator, in which the piezoelectric diaphragm having the vibrating portion is sealed with a sealing member, can reduce the thickness of the piezoelectric vibrator itself.

[0004] Furthermore, as various electronic devices become smaller, there is a demand for smaller packages for piezoelectric resonator devices in which the piezoelectric resonator and integrated circuit element are mounted on a substrate. Therefore, piezoelectric resonator devices are known in which the piezoelectric resonator and integrated circuit element are mounted on the substrate in a stacked structure. For example, the piezoelectric resonator device described in Patent Document 1 has a quartz resonator, which is made up of a first sealing member, a second sealing member, and a quartz resonator plate with excitation electrodes formed on both main surfaces, stacked together, and an electronic component element, mounted on a function unit, which is a substrate connected to an external substrate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-139053 Summary of the Invention [Problem to be solved by the invention]

[0006] In the piezoelectric resonator device described in Patent Document 1, a quartz crystal resonator and an electronic component element mounted on one main surface of the function section are electrically connected to the mounting surface of an external substrate via the function section. One main surface of the function section has a circuit pattern that electrically connects the quartz crystal resonator and the electronic component element. The other main surface of the function section has an external connection terminal that is electrically connected to the external substrate.

[0007] The external connection terminals of the function unit are joined to the connection terminals of the external board via solder or the like. That is, the function unit is joined to the external board with the external connection terminals, the solder, and the connection terminals of the external board stacked on the mounting surface of the external board. Furthermore, the crystal unit having a stacked structure is mounted on the function unit. Piezoelectric resonator devices, such as the function unit, in which external connection terminals are formed on the outer bottom surface of a board connected to an external board, experience increased moments due to external impacts, vibrations, and the like as their overall height increases. That is, the force generated by the moment that separates the external connection terminals from the connection terminals of the external board increases as the overall height of the piezoelectric resonator device increases.

[0008] An object of the present invention is to provide a piezoelectric vibration device that can be firmly bonded to an external substrate at a position as close to the external substrate as possible. [Means for solving the problem]

[0009] The present inventors have studied a piezoelectric vibration device in which external connection terminals are unlikely to peel off from an external substrate even when subjected to external vibrations, shocks, etc. As a result of extensive research, the present inventors have come up with the following configuration.

[0010] A piezoelectric resonator device includes an insulating substrate having a wiring pattern including a plurality of pads on one of a pair of main surfaces, and an external connection terminal on the other main surface parallel to the one main surface, the external connection terminal being electrically connected to the wiring pattern and electrically connected to an external substrate, and on which at least a piezoelectric resonator and an integrated circuit element having an oscillation circuit are mounted. The insulating substrate has a recess on the other main surface. The external connection terminal is located within the recess, and a gap is provided between the outer edge of the external connection terminal and the side of the recess.

[0011] In the above-described configuration, the external connection terminals are located within the recesses of the insulating substrate, thereby reducing the amount of protrusion from the other main surface of the insulating substrate. As a result, the piezoelectric vibrating device is coupled to the external substrate at a position closer to the external substrate than when the external connection terminals are not located within the recesses. In other words, the overall height of the piezoelectric vibrating device can be made lower than when the external connection terminals are not located within the recesses. Furthermore, when bonding the piezoelectric vibrating device to the external substrate, a bonding material such as solder that bonds the external connection terminals to the external substrate fills the gap between the side surface of the recesses in the insulating substrate and the end face including the outer edge of the external connection terminals. Therefore, the external connection terminals are connected to the external substrate. substrate Not only the joint surface to be connected to the external connection terminal but also the end surface of the external connection terminal is connected to the external connection terminal by the joint material. substrate This allows the piezoelectric vibrating device to be firmly bonded to the external substrate at a position as close to the external substrate as possible.

[0012] From another viewpoint, it is preferable that the piezoelectric vibration device of the present invention includes the following configuration: the external connection terminal is located within the recess at a predetermined distance from the outer edge of the recess when viewed in a direction perpendicular to the other main surface.

[0013] In the above-described configuration, the bottom surface of the recess of the external connection terminal is exposed by a predetermined width from the outer edge of the recess so as to surround the external connection terminal when viewed in a direction perpendicular to the other main surface. Therefore, the external connection terminal is connected to the external substrate not only at the bonding surface that is connected to the external substrate by the bonding material but also at the end surface of the external connection terminal and the bottom surface of the recess. This allows the piezoelectric resonator device to be firmly bonded to the external substrate at a position as close to the external substrate as possible.

[0014] From another viewpoint, it is preferable that the piezoelectric vibration device of the present invention includes the following configuration: The thickness from the one main surface to a bonding surface of the external connection terminal that is electrically connected to the external substrate is less than the thickness from the one main surface to the other main surface.

[0015] In the above-described configuration, the bonding surface of the external connection terminal connected to the external substrate does not protrude from the other main surface of the insulating substrate. Therefore, the piezoelectric vibrating device is bonded to the external substrate at a position closer to the external substrate than if the external connection terminal were located on the other main surface. This allows the piezoelectric vibrating device to be firmly bonded to the external substrate at a position as close to the external substrate as possible.

[0016] From another viewpoint, the piezoelectric vibrating device of the present invention preferably includes the following configuration: The insulating substrate has one main surface, and at least one of the piezoelectric vibrator and the integrated circuit element is partially or entirely covered with resin.

[0017] In the above-described configuration, the piezoelectric resonator device is configured such that at least one of the piezoelectric resonator and the integrated circuit element is molded from resin, along with the insulating substrate, and thus the piezoelectric resonator and / or the integrated circuit element can be protected from external shocks and vibrations. Furthermore, the rigidity of the insulating substrate is improved by resin molding, so the external connection terminals are less likely to bend due to shocks and vibrations. This allows the piezoelectric resonator device to be firmly bonded to the external substrate.

[0018] From another viewpoint, it is preferable that the piezoelectric vibration device of the present invention includes the following configuration: In the insulating substrate, a portion of the internal wiring electrically connecting the wiring pattern and the external connection terminal, which is located on the other main surface side, is exposed and not covered by the base material of the insulating substrate.

[0019] In the above-described configuration, the piezoelectric vibrator has an internal wiring that connects the wiring pattern on the one main surface and the external connection terminal on the other main surface, and the internal wiring is insulated. sexual group When a part of the internal wiring is exposed in the recess, the composite material The piezoelectric vibrating device is bonded to the external substrate in a state where the wires extend upward and are exposed in the recess. This allows the piezoelectric vibrating device to be more firmly bonded to the external substrate.

[0020] From another viewpoint, the piezoelectric vibrating device of the present invention preferably includes the following configuration: The vibrator and the integrated circuit element are located on the same mounting surface of the insulating substrate.

[0021] In the above-described configuration, since the piezoelectric vibrator and the integrated circuit element are located on the same mounting surface of the insulating substrate, the overall height can be reduced compared to a configuration in which the piezoelectric vibrator is located on one main surface of the insulating substrate and the integrated circuit element is located on the other main surface. Therefore, the piezoelectric vibrator device can be bonded to the external substrate as close as possible to the external substrate. [Effects of the Invention]

[0022] According to one embodiment of the present invention, the external connection terminals are unlikely to peel off from the external substrate even when subjected to external shocks or vibrations. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a plan view of a piezoelectric vibration device according to a first embodiment of the present invention. [Figure 2]FIG. 2 is an exploded perspective view of a vibrator in the piezoelectric vibrating device according to the first embodiment of the present invention. [Figure 3] FIG. 3 is a plan view of a vibrator in the piezoelectric vibrating device according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a cross-sectional view taken along the arrow A in FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along the arrow A in FIG. 3, showing the piezoelectric vibration device according to the first embodiment of the present invention being resin-molded in a mold. [Figure 6] FIG. 6 is a bottom view of the piezoelectric vibration device according to the first embodiment of the present invention. [Figure 7] FIG. 7 is a cross-sectional view taken along the arrow B in FIG. [Figure 8] FIG. 8 is a side view showing a state in which the external connection terminals of the piezoelectric vibration device according to the first embodiment of the present invention are in contact with solder on the connection terminals of the external substrate. [Figure 9] FIG. 9 is a side view showing a state in which the external connection terminals of the piezoelectric vibration device according to the first embodiment of the present invention are joined to an external substrate by solder on the connection terminals of the external substrate. [Figure 10] FIG. 10 is a cross-sectional view taken along the arrow C in FIG. [Figure 11] FIG. 11 is a side view of a vibrator in a piezoelectric vibrating device according to a second embodiment of the present invention. [Figure 12] FIG. 12 is a cross-sectional view taken along the arrow D in FIG. [Figure 13] FIG. 13 is a bottom view of a vibrator in a piezoelectric vibrating device according to a second embodiment of the present invention. [Figure 14] FIG. 14 is a plan view of a piezoelectric vibration device according to a second embodiment of the present invention. [Figure 15] FIG. 15 is a plan view of a substrate in a piezoelectric vibration device according to a second embodiment of the present invention. [Figure 16] FIG. 16 is a cross-sectional view taken along the arrow F in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0024] Each embodiment will be described below with reference to the drawings. In each drawing, the same parts are denoted by the same reference numerals, and the description of the same parts will not be repeated. Note that the dimensions of the components in each drawing do not faithfully represent the actual dimensions of the components and the dimensional ratios of each component. Note that in the following embodiments, the term "main surface" refers to the surface with the largest area in the target component, or the surface with the largest area visible when viewed in the thickness direction in the case of a plate-like component.

[0025] In the following description of the piezoelectric vibration device 1 according to an embodiment of the present invention, the longitudinal direction of the vibrator 2 and the substrate 11 is referred to as the "X direction," the lateral direction as the "Y direction," and the direction of the opening of the frame portion 4 of the vibrator 2, which is perpendicular to the X and Y directions, and the direction perpendicular to the main surface of the substrate 11, as the "Z direction." In this embodiment, the X and Y directions are directions on a horizontal plane. The Z direction is the vertical direction. However, these definitions of directions are not intended to limit the orientation of the piezoelectric vibration device 1 during use.

[0026] Furthermore, in the following description, expressions such as "fix," "connect," "join," and "attach" (hereinafter referred to as "fixing") include not only cases where members are directly fixed to each other, but also cases where members are fixed via other members. In other words, in the following description, expressions such as "fixing" include both direct and indirect fixing of members to each other.

[0027] [Embodiment 1] <Configuration of Piezoelectric Vibration Device 1> A piezoelectric vibration device 1 of the present invention will be described using Figs. 1 to 5. Fig. 1 is a plan view showing an outline of the overall configuration of the piezoelectric vibration device 1. Fig. 2 is an exploded perspective view showing an outline of the overall configuration of a vibrator 2 in the piezoelectric vibration device 1. Fig. 3 is a plan view of the vibrator 2. Fig. 4 is a cross-sectional view taken along the arrow A in Fig. 3. Fig. 5 is a cross-sectional view taken along the arrow A in Fig. 3, showing the piezoelectric vibration device 1 in a state where it has been resin-molded in a mold W. Fig. 6 is a bottom view showing an outline of the overall configuration of the piezoelectric vibration device 1.

[0028] As shown in FIG. 1, the piezoelectric vibration device 1 includes a vibrator 2, an integrated circuit element 10, a substrate 11, and a molded part 12 (see FIG. 5).

[0029] 2 to 4, the vibrator 2 is a piezoelectric element having a piezoelectric body that converts an applied force into a voltage or converts an applied voltage into a force. The vibrator 2 has a piezoelectric diaphragm 3, a first sealing member 7, a second sealing member 8, and a protective member 9.

[0030] The piezoelectric diaphragm 3 is a rectangular quartz crystal vibrating piece cut in a specific direction from quartz crystal. The piezoelectric diaphragm 3 has a frame portion 4, a vibrating portion 5, and a connecting portion 6. The frame portion 4, vibrating portion 5, and connecting portion 6 of the piezoelectric diaphragm 3 are integrally molded. In other words, the frame portion 4, vibrating portion 5, and connecting portion 6 are configured as a single member.

[0031] As shown in Figures 3 and 4, the frame 4 is a member that surrounds the periphery of the vibrating unit 5. The frame 4 is made of a rectangular plate material in a plan view that is perpendicular to the pair of principal surfaces that have the largest areas. The frame 4 is a frame-shaped member in which the pair of principal surfaces each have a rectangular opening when viewed in the Z direction in a plan view. In other words, the frame 4 has a rectangular through-hole 4c that penetrates from one of the principal surfaces to the other of the principal surfaces.

[0032] The distance between the pair of main surfaces of the frame 4, which is the thickness of the frame 4, is t1. One main surface of the frame 4 has a first bonding surface 4a that bonds with the first sealing member 7. The other main surface of the frame 4 has a second bonding surface 4b that bonds with the second sealing member 8. Both ends of the frame 4 in the longitudinal direction each have a vibrator mounting terminal 4d.

[0033] The vibrating section 5 is a piezoelectric body. The vibrating section 5 is a plate material that is approximately rectangular in plan view, which is the direction perpendicular to the pair of principal surfaces with the largest area. The vibrating section 5 is located within the frame section 4. The vibrating section 5 is located so that the pair of principal surfaces face the opening of the frame section 4 when viewed in the Z direction in plan view. The principal surfaces of the vibrating section 5 are also located approximately parallel to the principal surfaces of the frame section 4. The distance between the pair of principal surfaces of the vibrating section 5, which is the thickness of the vibrating section 5, is a thickness t2 that is thinner than the thickness t1 of the frame section 4. The vibrating section 5 is located between the pair of principal surfaces of the frame section 4 within the frame section 4.

[0034] A portion of the vibration section 5 is connected to the frame section 4 via a plate-shaped connecting section 6. The vibration section 5 is held in a cantilevered state by the frame section 4 via the connecting section 6. In other words, the vibration section 5 is surrounded by the frame section 4 with the through-hole 4c in between. One main surface of the vibration section 5 has a first excitation electrode 5a. The other main surface of the vibration section 5 has a second excitation electrode 5b. The first excitation electrode 5a is connected to one of the vibrator mounting terminals 4d. The second excitation electrode 5b is connected to the other vibrator mounting terminal 4d.

[0035] The first sealing member 7 and the second sealing member 8 are sealing members that seal the inside of the frame portion 4. The first sealing member 7 and the second sealing member 8 are resin films that are rectangular in plan view in a direction perpendicular to the pair of main surfaces having the largest areas. The first sealing member 7 and the second sealing member 8 are films made of polyimide resin that have heat resistance of about 300°C, for example. The first sealing member 7 and the second sealing member 8 also have a thickness t3 of about 20 μm to 50 μm.

[0036] The width X3 in the X direction, which is the longitudinal direction, of the first sealing member 7 and the second sealing member 8, when viewed in the Z direction as a plan view, is smaller than the width X1 in the X direction at the outer edge of the frame portion 4 and is larger than the width X2 in the X direction at the opening portion, which is the inner edge of the frame portion 4. Furthermore, the width Y3 in the Y direction, which is the short side direction perpendicular to the X direction, of the first sealing member 7 and the second sealing member 8, when viewed in the Z direction, is smaller than the width Y1 in the Y direction at the outer edge of the frame portion 4 and is larger than the width Y2 in the Y direction at the opening portion, which is the inner edge of the frame portion 4. In other words, the first sealing member 7 and the second sealing member 8 are smaller than the frame portion 4 and larger than the opening portion of the frame portion 4.

[0037] The first sealing member 7 is bonded to a first bonding surface 4a on one main surface of the frame 4 with a bonding material 13, which is a thermoplastic adhesive. The periphery of the first sealing member 7 is located inward from the outer edge of the frame 4 and outward from the inner edge of the frame 4. The X-direction end of the first sealing member 7 is bonded to the first bonding surface 4a on one main surface of the frame 4, which is located in the X direction. The Y-direction end of the first sealing member 7 is bonded to the first bonding surface 4a on one main surface of the frame 4, which is located in the Y direction. In other words, when viewed in the Z direction, the portion of the first sealing member 7 that overlaps with the first bonding surface 4a is bonded to the frame 4 with the bonding material 13. The first sealing member 7 covers the opening on one main surface of the frame 4. As a result, the first sealing member 7 blocks the opening on one main surface of the frame 4.

[0038] The second sealing member 8 is bonded to the second bonding surface 4b of the other main surface of the frame 4 by a bonding material 13. The periphery of the second sealing member 8 is located inside the outer edge of the frame 4 and outside the inner edge of the frame 4. The end of the second sealing member 8 in the X direction is bonded to the second bonding surface 4b located in the X direction on the other main surface of the frame 4. The end of the second sealing member 8 in the Y direction is bonded to the second bonding surface 4b located in the Y direction on the other main surface of the frame 4. In other words, when viewed in the Z direction, the portion of the second sealing member 8 that overlaps with the second bonding surface 4b is bonded to the frame 4 by a bonding material 13. The second sealing member 8 is bonded to the frame 4 by a bonding material 13. On the other handAs a result, the second sealing member 8 closes the opening in the other main surface of the frame portion 4.

[0039] The protective member 9 is a member that suppresses deflection of at least the first sealing member 7 out of the first sealing member 7 or the second sealing member 8 due to the molding pressure of the resin that constitutes the molded portion 12. The protective member 9 is a rectangular plate-like member when viewed in a plan view perpendicular to the pair of principal surfaces with the largest area. The protective member 9 is made of silicon, which is a brittle material. It is desirable that the protective member 9 has enough rigidity to limit the maximum deflection to 20 μm or less when supported at both ends in the longitudinal direction when pressure generated during resin molding is applied.

[0040] Therefore, the modulus of longitudinal elasticity and the moment of inertia in the Z direction, which is the direction in a plan view, of the protective member 9 are determined so that the protective member 9 has a higher rigidity than at least the first sealing member 7 out of the first sealing member 7 and the second sealing member 8. In this embodiment, the protective member 9 is made of silicon. In this embodiment, the protective member 9 preferably has a thickness t4 of approximately 30 μm to 100 μm. The thickness t4 of the protective member 9 is greater than the thicknesses t3 of the first sealing member 7 and the second sealing member 8.

[0041] When viewed in the Z direction, the width X4 in the X direction, which is the longitudinal direction of the protective member 9, is smaller than the width X1 in the X direction at the outer edge of the frame portion 4 of the piezoelectric diaphragm 3, and is larger than the width X3 in the X direction of the first sealing member 7. Furthermore, when viewed in the Z direction, the width Y4 in the Y direction, which is the direction perpendicular to the X direction, of the protective member 9 is smaller than the width Y1 in the Y direction at the outer edge of the frame portion 4, and is larger than the width Y3 in the Y direction of the first sealing member 7. In other words, the protective member 9 is smaller than the frame portion 4 and larger than the first sealing member 7.

[0042] The protective member 9 is bonded to a surface of the first sealing member 7 perpendicular to the Z direction with a bonding material 13, which is a thermoplastic adhesive or die attach agent. The peripheral edge of the protective member 9 is located between the peripheral edge of the first sealing member 7 and the outer edge of the frame 4. In other words, the peripheral edge of the protective member 9 overlaps with the first bonding surface 4a of the frame 4 when viewed in the Z direction. This allows the peripheral edge of the protective member 9 to be supported by the frame 4. Furthermore, the protective member 9 covers an opening portion on one main surface of the frame 4 via the first sealing member 7. In other words, the protective member 9 covers the entire first sealing member 7, including the portion that overlaps with the opening portion when viewed in the Z direction.

[0043] The vibrator 2 configured as described above has a three-layer structure including a piezoelectric diaphragm 3, a first sealing member 7 that closes an opening on one main surface of the piezoelectric diaphragm 3, and a second sealing member 8 that closes an opening on the other main surface of the piezoelectric diaphragm 3. The vibrator 2 has an internal space S defined by the frame 4 of the piezoelectric diaphragm 3, the first sealing member 7, and the second sealing member 8. The vibrator 2 has a vibrating part 5 located within the internal space S. An inert gas such as nitrogen gas is sealed within the internal space S. The vibrator 2 oscillates at a predetermined frequency when a voltage is applied from each vibrator mounting terminal 4d.

[0044] As shown in Fig. 1, the integrated circuit element 10 is an IC that controls the vibrator 2. The integrated circuit element 10 has electronic circuits such as an oscillation circuit that is connected to a temperature-sensitive element (thermistor) that detects the ambient temperature and generates a predetermined oscillation output. The integrated circuit element 10 outputs the oscillation output generated by the oscillation circuit as a reference signal such as a clock signal to the outside through the integrated circuit element mounting terminals 10a. The integrated circuit element 10 is covered with resin except for the integrated circuit element mounting terminals 10a.

[0045] As shown in FIG. 1, the substrate 11 is an insulating substrate that electrically connects and integrally configures the vibrator 2 and the integrated circuit element 10 via a wiring pattern (not shown). The substrate 11 is made of a resin material. The substrate 11 is based on, for example, glass epoxy resin, which is an insulator that is easy to process, such as by cutting. The substrate 11 can easily configure a piezoelectric vibrating device 1 having any shape. The substrate 11 is a rectangular plate material. In this embodiment, the thickness of the substrate 11 is, for example, 0.17 mm. One of the pair of main surfaces of the substrate 11 is configured as a first mounting surface 11a having the wiring pattern including pads, lands, etc. formed of a conductor such as copper.

[0046] A resonator 2 and an integrated circuit element 10 are mounted on the first mounting surface 11a of the substrate 11. Both resonator mounting terminals 4d of the resonator 2 are electrically connected to the wiring pattern on the first mounting surface 11a by conductive bonding material 13. The resonator 2 is disposed with its main surface, covered by the first sealing member 7 and the second sealing member 8, facing the Z direction. The resonator 2 is positioned such that the second sealing member 8 faces the first mounting surface 11a. The second sealing member 8 is in contact with the first mounting surface 11a. Similarly, the integrated circuit element mounting terminals 10a of the integrated circuit element 10 are electrically connected to the wiring pattern on the first mounting surface 11a of the substrate 11 by conductive bonding material 13. In this manner, the resonator 2 and the integrated circuit element 10 are positioned side by side on the first mounting surface 11a of the substrate 11.

[0047] 6, the other main surface of the substrate 11 parallel to one main surface is configured as a second mounting surface 11b having external connection terminals 11d for mounting on an external substrate P. The external connection terminals 11d are plate-shaped terminals made of conductive metal. The wiring pattern on the first mounting surface 11a is electrically connected to the external connection terminals 11d via internal wiring 11c.

[0048] The vibrator 2 mounted on the substrate 11 is electrically connected to an external substrate P from the vibrator mounting terminal 4d via a wiring pattern (not shown) on the first mounting surface 11a, internal wiring 11c, and external connection terminal 11d on the second mounting surface 11b (see FIG. 9). Furthermore, the vibrating portion 5 of the vibrator 2 is held in a cantilevered state on the frame portion 4 of the piezoelectric diaphragm 3 by a connecting portion 6. This causes the vibrating portion 5 to oscillate at a predetermined frequency in response to a voltage applied from the external substrate P.

[0049] As shown in FIG. 5, the molded part 12 protects at least the resonator 2 out of the substrate 11 and the resonator 2 and integrated circuit element 10 mounted on the substrate 11 (see FIG. 6). The molded part 12 is a thermosetting resin such as epoxy resin 12a. The molded part 12 covers at least a part of the resonator 2 out of the substrate 11 and the resonator 2 and integrated circuit element 10 mounted on the substrate 11 with the thermoset epoxy resin 12a. In this embodiment, the molded part 12 covers the substrate 11 and the resonator 2 and integrated circuit element 10 mounted on the substrate 11.

[0050] The vibrator 2 of the piezoelectric vibration device 1 configured in this manner has a three-layer structure in which the piezoelectric vibration plate 3, which supports the vibration section 5, thinner than the frame section 4, within the frame section 4, is covered with a first sealing member 7 and a second sealing member 8, which are resin films. Therefore, the overall height of the piezoelectric vibration device 1 can be reduced compared to a piezoelectric vibration device having a vibrator in which the vibration section is held by a box-shaped holding member and sealed with a lid member. In addition, the protective member 9 covers the first sealing member 7 with its periphery supported by the frame section 4. Because the vibrator 2 covers the first sealing member 7 with the protective member 9, the resistance of the first sealing member 7 to molding pressure from the mold resin is improved.

[0051] Next, the second mounting surface 11b and the external connection terminals 11d of the substrate 11 will be described in detail with reference to Figures 6 and 7. Figure 7 is a cross-sectional view taken along the arrow B in Figure 6. In this embodiment, the second mounting surface 11b has four external connection terminals 11d.

[0052] As shown in FIGS. 6 and 7, the second mounting surface 11b of the substrate 11 is the other main surface electrically connected to the external substrate P. The second mounting surface 11b has four recesses 11g corresponding to the four external connection terminals 11d. Each of the four recesses 11g is a stepped portion recessed in a direction perpendicular to the second mounting surface 11b over an arbitrarily determined range. Each of the four recesses 11g has a bottom surface 11h parallel to the second mounting surface 11b and a side surface 11i perpendicular to the second mounting surface 11b. The four recesses 11g are located at four corners including vertices that are intersections of the long and short sides of the substrate 11 when viewed in the Z direction. Each of the four recesses 11g is recessed over a range that includes a portion of the long side and a portion of the short side, which are the outer edge of the substrate 11 extending from the vertex. In this embodiment, three of the four recesses 11g are rectangular when viewed in the Z direction. Another one of the four recesses 11g is pentagonal.

[0053] The external connection terminal 11d is On the other hand The main surfaces of the external connection terminals 11d are configured as terminals that bond to the connection terminals P1 of the external substrate P. The four external connection terminals 11d are located in the four recesses 11g, respectively. When viewed in the Z direction, the external connection terminals 11d have bonding surfaces 11e on their main surfaces that bond to the connection terminals P1. The bonding surfaces 11e are exposed and not covered by the insulating base material of the substrate 11. The bonding surfaces 11e are parallel to the second mounting surface 11b.

[0054] 6, the external connection terminal 11d is smaller than the bottom surface 11h when viewed in the Z direction. Therefore, the external connection terminal 11d is contained within the bottom surface 11h when viewed in the Z direction. Furthermore, the external connection terminal 11d is located within the recess 11g at a predetermined distance from the outer edge of the bottom surface 11h. In other words, the end surface 11f, which includes four end surfaces 11fa, 11fb, 11fc, and 11fd including the outer edge of the external connection terminal 11d, is located away from the outer edge of the bottom surface 11h so that a predetermined gap G is formed inside the recess 11g.

[0055] The end face 11fa adjacent to one side face 11i of the recess 11g and the end face 11fb adjacent to the other side face 11i are positioned with a gap G1 from the side face 11i when viewed in the Z direction. The end face 11fc adjacent to the short side of the substrate 11 included in the recess 11g and the end face 11fd adjacent to the long side of the substrate 11 are positioned with a predetermined gap G2 from the long side or short side of the substrate 11 when viewed in the Z direction. Thus, the external connection terminal 11d has four end faces 11fa, 11fb, 11fc, and 11fd that form its outer edge exposed. The bottom face 11h of the recess 11g is exposed around the external connection terminal 11d. A groove is formed around the external connection terminal 11d by the side face 11i of the recess 11g, the bottom face 11h of the recess 11g, and the end face 11f of the external connection terminal 11d.

[0056] Furthermore, the internal wiring 11c is connected to the external connection terminal 11d. The internal wiring 11c is made of a conductive metal. The internal wiring 11c electrically connects the wiring pattern on the first mounting surface 11a and the external connection terminal 11d. The internal wiring 11c passes through the inside of the substrate 11 and is located within the recess 11g. The internal wiring 11c is connected to at least one of the four end faces 11fa, 11fb, 11fc, and 11fd of the external connection terminal 11d within the recess 11g. The internal wiring 11c protrudes from the end face 11f to which it is connected toward the side face 11i of the recess 11g when viewed in the Z direction. The internal wiring 11c does not protrude beyond the bonding surface 11e of the external connection terminal 11d. The internal wiring 11c is not covered by the substrate base material of the substrate 11 within the recess 11g. In other words, like the external connection terminal 11d, the internal wiring 11c is exposed and not covered by the insulating substrate base material of the substrate 11.

[0057] A thickness t1 from the first mounting surface 11a of the substrate 11 to the bonding surface 11e of the external connection terminal 11d is less than a thickness t0 of the substrate 11, which is a thickness from the first mounting surface 11a to the second mounting surface 11b. In other words, the bonding surface 11e of the external connection terminal 11d does not protrude beyond the second mounting surface 11b of the substrate 11. Thus, the recess amount of the recess 11g is greater than the thickness of the external connection terminal 11d.

[0058] Next, referring to FIGS. 8 to 10, the substrate 11 is connected to the external substrate P to The joining method will now be described. Fig. 8 is a side view showing a state in which the external connection terminal 11d of the piezoelectric resonator device 1 is in contact with the solder H on the connection terminal P1 of the external substrate P. Fig. 9 is a side view showing a state in which the external connection terminal 11d of the piezoelectric resonator device 1 is joined to the external substrate P by the solder H on the connection terminal P1 of the external substrate P. Fig. 10 is a cross-sectional view taken along the arrow C in Fig. 9.

[0059] As shown in FIG. 8, the external connection terminals 11d are joined to connection terminals of an external substrate P with solder H. The four external connection terminals 11d of the substrate 11 are joined to corresponding connection terminals P1 on the external substrate P with solder H applied thereto. The solder H joins the connection terminals P1 and the external connection terminals 11d, thereby joining the external substrate P and the substrate 11. By bringing the substrate 11 closer to the external substrate P, the solder H of the external substrate P adheres to the joining surface 11e of the external connection terminals 11d. As the substrate 11 is pressed against the external substrate P, the solder H spreads toward the outer edge of the external connection terminals 11d.

[0060] 9 and 10, when the solder H reaches the outer edge of the external connection terminal 11d, it penetrates from the joining surface 11e into the gap G1 between the side surface 11i of the recess 11g and the end surfaces 11fa and 11fb of the external connection terminal 11d (see FIG. 6). The solder H covers the joining surface 11e and four end surfaces 11f of the external connection terminal 11d and the internal wiring 11c exposed on the bottom surface 11h of the recess 11g of the substrate 11. The solder H is bonded to the joining surface 11e and four end surfaces 11f of the external connection terminal 11d, and also to the internal wiring 11c exposed on the bottom surface 11h of the recess 11g of the substrate 11. Note that the solder H may be bonded to the joining surface 11e, four end surfaces 11f, and internal wiring 11c while being in physical contact with the side surface 11i of the recess 11g.

[0061] Furthermore, the solder H of the external substrate P that is attached to the bonding surface 11e of the external connection terminal 11d spreads toward the internal wiring 11c that is connected to at least one of the four end faces 11fa, 11fb, 11fc, and 11fd. The solder H covers the internal wiring 11c in the external connection terminal 11d. The solder H is bonded to the internal wiring 11c in the external connection terminal 11d in a state where it creeps up.

[0062] The piezoelectric vibration device 1 configured in this manner has a three-layer piezoelectric vibrator in which each main surface of the piezoelectric vibration plate 3 is sealed with a first sealing member 7 and a second sealing member 8, which are resin films. Therefore, the overall height of the piezoelectric vibration device 1 can be reduced compared to a configuration having a piezoelectric vibrator in which a box-shaped holding member made of ceramic or the like is sealed with a lid member.

[0063] Furthermore, in the piezoelectric vibration device 1, the vibrator 2 and the integrated circuit element 10 are mounted on the same first mounting surface 11a of the substrate 11. Therefore, the overall height of the piezoelectric vibration device 1 can be reduced compared to a configuration in which the vibrator 2 is mounted on the first mounting surface 11a of the substrate 11 and the integrated circuit element 10 is mounted on the second mounting surface 11b.

[0064] Furthermore, the external connection terminals 11d in the recess 11g are located closer to the first mounting surface 11a than the second mounting surface 11b. Therefore, the piezoelectric vibrating device 1 is bonded to the external substrate P at a position closer to the external substrate P than when the external connection terminals 11d are not located in the recess 11g. In other words, the external substrate P to which the piezoelectric vibrating device 1 is bonded can have a lower overall height than when the external connection terminals 11d of the piezoelectric vibrating device 1 are located on the second mounting surface 11b.

[0065] The piezoelectric resonator device 1 has a molded portion 12 that covers the substrate 11 and at least one of the resonator 2 and the integrated circuit element 10 with resin, thereby protecting at least one of the resonator 2 and the integrated circuit element 10 from external impacts and vibrations. In addition, the rigidity of the substrate 11 is improved by the molded portion 12, making the external connection terminals 11d less likely to bend due to impacts and vibrations. Therefore, the piezoelectric resonator device 1 suppresses distortion that occurs at the joint surfaces 11e between the external connection terminals 11d and the solder H due to external impacts and vibrations.

[0066] The external connection terminal 11d has a larger bonding area with the solder H than when only the bonding surface 11e is bonded with the solder H. Therefore, the substrate 11 has a stronger bonding strength with the external substrate P than when only the bonding surface 11e is bonded to the connection terminal P1 of the external substrate P by the solder H. This allows the piezoelectric resonator device 1 to be firmly bonded to the external substrate P at a position as close to the external substrate P as possible.

[0067] [Embodiment 2] <Configuration of the piezoelectric vibration device 21> Next, a piezoelectric vibration device 21 according to a second embodiment of the present invention will be described with reference to Figs. 11 to 16. Fig. 11 is a side view of a vibrator 22 in the piezoelectric vibration device 21 according to the second embodiment of the present invention. Fig. 12 is a cross-sectional view taken along the arrow D in Fig. 11. Fig. 13 is a bottom view of the vibrator 22 in the piezoelectric vibration device 21. Fig. 14 is a plan view of the piezoelectric vibration device 21. Fig. 15 is a plan view of the substrate 31 in the piezoelectric vibration device 21. Fig. 16 is a cross-sectional view of the vibrator 22 in Fig. 15. F It should be noted that in the following embodiments, specific descriptions of the same points as in the embodiments already described will be omitted, and the description will focus on the differences.

[0068] As shown in FIG. 14, a piezoelectric vibration device 21 includes a vibrator 22, an integrated circuit element 30, a substrate 31, and a molded part (not shown).

[0069] Figure 12 13, vibrator 22 is a piezoelectric vibrator having piezoelectric diaphragm 23, first sealing member 26, and second sealing member 27. Vibrator 22 has a sandwich structure in which piezoelectric diaphragm 23 is sandwiched between first sealing member 26 and second sealing member 27.

[0070] As shown in FIG. 12 , the piezoelectric diaphragm 23 is a plate-like member made of quartz crystal, a piezoelectric material. One and the other main surfaces of the piezoelectric diaphragm 23 have a pair of excitation electrodes 24a. The pair of excitation electrodes 24a are positioned so as to face each other in the thickness direction of the piezoelectric diaphragm 23. Furthermore, when viewed in the Z direction, which is a plan view, the piezoelectric diaphragm 23 has a notch 24b penetrating from one main surface to the other so as to surround the pair of excitation electrodes 24a. The notch 24b penetrates so as to surround the pair of excitation electrodes 24a except for one. As a result, the portion where the pair of excitation electrodes 24a are located is configured as a cantilevered plate-like member. In other words, the portion where the pair of excitation electrodes 24a are located is configured as a vibration part 24 that can vibrate in the Z direction.

[0071] The piezoelectric diaphragm 23 has, on one main surface thereof, a bonding material 25 that is bonded to the first sealing member 26 so as to surround the vibration portion 24. Similarly, the piezoelectric diaphragm 23 has, on the other main surface thereof, a bonding material 25 that is bonded to the first sealing member 26 so as to surround the vibration portion 24. 27 The bonding material 25 is a PVD film made of the same metal as that of the pair of excitation electrodes 24a.

[0072] The first sealing member 26 is a member that seals the vibrating portion 24 of the piezoelectric diaphragm 23. The first sealing member 26 is a plate-shaped member made of the same quartz crystal as the piezoelectric diaphragm 23. The first sealing member 26 has substantially the same shape as the piezoelectric diaphragm 23. In other words, when one main surface of the first sealing member 26 is placed opposite one main surface of the piezoelectric diaphragm 23, the one main surface of the first sealing member 26 is shaped so that it can cover the entire one main surface of the piezoelectric diaphragm 23. The first sealing member 26 has, on one main surface thereof, a bonding material 25 that bonds to the bonding material 25 of the piezoelectric diaphragm 23. The bonding material 25 of the first sealing member 26 is a PVD film made of the same metal as the metal that makes up the bonding material 25 of the piezoelectric diaphragm 23.

[0073] As shown in FIG. 11 , the second sealing member 27 is a member that seals the vibrating portion 24 of the piezoelectric diaphragm 23. The second sealing member 27 is a plate-shaped member made of the same quartz crystal as the piezoelectric diaphragm 23. The second sealing member 27 has substantially the same shape as the piezoelectric diaphragm 23. In other words, when one main surface of the second sealing member 27 is placed opposite the other main surface of the piezoelectric diaphragm 23, the one main surface of the second sealing member 27 can cover the entire other main surface of the piezoelectric diaphragm 23. The second sealing member 27 has, on one main surface, a bonding material 25 that bonds to the bonding material 25 of the piezoelectric diaphragm 23. The second sealing member 27 The bonding material 25 is Piezoelectric diaphragm 23 The PVD film is made of the same metal as the metal that forms the bonding material 25.

[0074] The second sealing member 27 has, on the other main surface thereof, four vibrator mounting terminals 27a that are electrically connected to the electrodes of the substrate 31. The four vibrator mounting terminals 27a are plate-shaped terminals made of conductive metal. The four vibrator mounting terminals 27a are configured in a substantially L-shape when viewed in the Z direction.

[0075] A first sealing member 26 is positioned on one main surface of the piezoelectric diaphragm 23. One main surface of the piezoelectric diaphragm 23 is covered with the first sealing member 26. At this time, the bonding material 25 on one main surface of the piezoelectric diaphragm 23 and the bonding material 25 of the first sealing member 26 are diffusion bonded together. As a result, the excitation electrode 24a on one main surface of the piezoelectric diaphragm 23 is hermetically sealed by the first sealing member 26.

[0076] A second sealing member 27 is positioned on the other main surface of the piezoelectric diaphragm 23. The other main surface of the piezoelectric diaphragm 23 is covered with the second sealing member 27. At this time, the bonding material 25 on the other main surface of the piezoelectric diaphragm 23 and the bonding material 25 of the second sealing member 27 are diffusion bonded to each other. As a result, the excitation electrode 24a on the other main surface side of the piezoelectric diaphragm 23 is hermetically sealed by the second sealing member 27.

[0077] The vibrator 22 configured in this manner is configured as a sandwich-structured package in which both main surfaces of the piezoelectric diaphragm 23 are sealed with a first sealing member 26 and a second sealing member 27. Furthermore, by covering both main surfaces of the piezoelectric diaphragm 23 with the first sealing member 26 and the second sealing member 27, an internal space is formed in the vibrator 22 that contains the vibrating part 24 of the piezoelectric diaphragm 23. In other words, the vibrator 22 has the vibrating part 24, which includes a pair of excitation electrodes 24a, hermetically sealed in the internal space of the package.

[0078] 14, the integrated circuit element 30 is an IC that controls the vibrator 22. The configuration of the integrated circuit element 30 is the same as that of the integrated circuit element 10 of the first embodiment, and therefore a description thereof will be omitted.

[0079] The substrate 31 is a member that electrically connects and integrally configures the vibrator 22 and the integrated circuit element 30 via a wiring pattern. One of a pair of main surfaces of the substrate 31 is configured as a first mounting surface 31a having the wiring pattern including four connection terminals 31d, pads, lands, etc., formed of a conductor such as copper. The four connection terminals 31d are electrically connected to the wiring pattern including a plurality of pads on the first mounting surface 31a via internal wiring 31c.

[0080] The vibrator 22 and the integrated circuit element 30 are mounted on the first mounting surface 31a of the substrate 31. The vibrator 22 is disposed on the substrate 31 with the second sealing member 27 facing the first mounting surface 31a (see FIG. 16). Four vibrator mounting terminals 27a (see FIG. 13) of the second sealing member 27 are electrically connected to four connection terminals 31d on the first mounting surface 31a by conductive solder H (see FIG. 16). Similarly, the integrated circuit element mounting terminals 30a of the integrated circuit element 30 are electrically connected to the wiring pattern on the first mounting surface 31a of the substrate 31 by conductive solder H. In this way, the vibrator 22 and the integrated circuit element 30 are positioned side by side on the first mounting surface 31a of the substrate 31.

[0081] 16, the other main surface of the substrate 31 parallel to the one main surface is configured as a second mounting surface 31b having external connection terminals 31j for mounting on an external substrate P (see FIG. 9). The external connection terminals 31j are plate-shaped terminals made of conductive metal. The external connection terminals 31j are electrically connected to the wiring pattern including multiple pads on the first mounting surface 31a via internal wiring 31c (not shown).

[0082] The molded part (not shown) protects at least the vibrator 22 of the substrate 31 and the vibrator 22 and integrated circuit element 30 mounted on the substrate 31. The molded part is similar to the molded part 12 in the first embodiment, and therefore a description thereof will be omitted.

[0083] 14 to 16, the first mounting surface 31a and the connection terminals 31d of the substrate 31 will be described in detail. Note that the second mounting surface 31b of the substrate 31 is the same as the second mounting surface 11b of the substrate 11 in the first embodiment, and therefore the description thereof will be omitted.

[0084] As shown in Figures 14 to 16, the first mounting surface 31a of the substrate 31 is one of the main surfaces electrically connected to the vibrator 22 and the integrated circuit element 30. The first mounting surface 31a has four recesses 31g (hereinafter simply referred to as "recesses 31g"). When viewed in the Z direction, the recesses 31g are positioned so as to be line-symmetric with respect to the X and Y directions. Each recess 31g has a substantially L-shaped area recessed in a direction perpendicular to the first mounting surface 31a. Each recess 31g has a bottom surface 31h parallel to the first mounting surface 31a and a side surface 31i perpendicular to the first mounting surface 31a. The recesses 31g are On the other hand The recesses 31g are shaped so that the vibrator mounting terminals 27a of the vibrators 22, with their main surfaces facing the bottom surface 31h, can be placed inside them. Approximately L-shaped connection terminals 31d are located within the recesses 31g. In other words, the substrate 31 has four connection terminals 31d. The connection terminals 31d are plate-shaped terminals made of conductive metal.

[0085] As shown in Fig. 16, the connection terminals 31d protrude in the Z direction from the bottom surface 31h of each recess 31g. The main surfaces perpendicular to the Z direction of the four connection terminals 31d (hereinafter simply referred to as "connection terminals 31d") are configured as bonding surfaces 31e that are bonded to the four vibrator mounting terminals 27a of the vibrator 22, respectively. The connection terminals 31d are Recess 31g The connecting terminals 31d are positioned in their respective recesses 31g so as to leave a predetermined gap G3 between the connecting terminals 31d and the side surfaces 31i. The bonding surfaces 31e are exposed and not covered by the insulating base material of the substrate 31. The bonding surfaces 31e of the connecting terminals 31d are positioned closer to the bottom surface 31h than the first mounting surface 31a. In other words, the bonding surfaces 31e are recessed from the first mounting surface 31a.

[0086] 14, connection terminal 31d has end surface 31f perpendicular to bottom surface 31h of recess 31g at its outer edge. The width X5 in the X direction of two connection terminals 31d aligned in the X direction is wider than the width of vibrator 22 in the X direction. Furthermore, the width Y5 in the Y direction of two connection terminals 31d aligned in the Y direction is wider than the width of vibrator 22 in the Y direction. In other words, connection terminals 31d extend further in both the X and Y directions than the outer edge of vibrator 22 when viewed in the Z direction.

[0087] Furthermore, internal wiring 31c is connected to the connection terminals 31d. The internal wiring 31c is made of a conductive metal. The internal wiring 31c electrically connects the wiring pattern on the first mounting surface 31a and the external connection terminals 31j. The internal wiring 31c is connected to each connection terminal 31d within the recess 31g. The internal wiring 31c does not protrude beyond the bonding surface 31e of the connection terminal 31d. The internal wiring 31c is not covered by the base material of the substrate 31 within the recess 31g. In other words, the internal wiring 31c, like the connection terminals 31d, is exposed and not covered by the insulating base material of the substrate 31.

[0088] Next, the bonding between the vibrator 22 and the substrate 31 will be described with reference to FIGS.

[0089] 14, the vibrator 22 is disposed on the first mounting surface 31a with the other main surface of the second sealing member 27 facing the bottom surface 31h of the recess 31g. The side surfaces 31i of the recesses 31g are located around the outer edge of the vibrator 22. Furthermore, when viewed in the Z direction, a portion of each connection terminal 31d is located between the outer edge of the vibrator 22 and the side surfaces 31i.

[0090] 14 and 16, the four vibrator mounting terminals 27a of the vibrator 22 are joined by solder H applied to the four connection terminals 31d of the substrate 31. Each solder H is in close contact with the vibrator mounting terminal 27a and also with the connection terminal 31d. The solder H located between the vibrator mounting terminal 27a and the connection terminal 31d spreads toward the outer edge of the connection terminal 31d as the vibrator 22 and the substrate 31 approach each other.

[0091] When each solder H reaches the outer edge of the connection terminal 31d, it spreads from the joining surface 31e toward the end surface 31f. 31e and end face 31f. That is, each solder H joins vibrator mounting terminal 27a of vibrator 22 to bonding surface 31e and end face 31f.

[0092] Furthermore, the solder H that has adhered to the joining surface 31e of the connection terminal 31d spreads toward the internal wiring 31c that is connected to the connection terminal 31d. The solder H covers the internal wiring 31c in the connection terminal 31d. The solder H joins the internal wiring 31c in the connection terminal 31d while covering it.

[0093] The vibrator 22 mounted on the substrate 31 is electrically connected to an external substrate (not shown) via four vibrator mounting terminals 27a, four connection terminals 31d on the first mounting surface 31a, a wiring pattern including multiple pads (not shown), internal wiring 31c, and external connection terminals 31j on the second mounting surface 31b. This causes the vibration section 5 of the vibrator 22 to oscillate at a predetermined frequency due to the voltage applied from the external substrate.

[0094] The piezoelectric vibration device 21 configured in this manner has a sandwich-structured vibrator 22 in which each main surface of the piezoelectric vibration plate 23 is sealed with a first sealing member 26 and a second sealing member 27, which are quartz plates. Therefore, the overall height of the piezoelectric vibration device 21 can be reduced compared to a configuration having a piezoelectric vibrator in which a box-shaped holding member made of ceramic or the like is sealed with a lid member.

[0095] Furthermore, in the piezoelectric vibrating device 21, the vibrator 22 and the integrated circuit element 30 are mounted on the same first mounting surface 31a of the substrate 31. Therefore, the overall height of the piezoelectric vibrating device 21 can be reduced compared to a configuration in which the vibrator 22 is mounted on the first mounting surface 31a of the substrate 31 and the integrated circuit element 30 is mounted on the second mounting surface 31b.

[0096] The piezoelectric vibration device 21 has a molded portion (not shown) that covers the substrate 31 and at least one of the vibrator 22 and the integrated circuit element 30 with resin, thereby protecting at least one of the vibrator 22 and the integrated circuit element 30 from external shocks and vibrations. Furthermore, the rigidity of the substrate 31 is improved by the molded portion, making the connection terminals 31d less likely to bend due to shocks and vibrations. Therefore, the piezoelectric vibration device 21 suppresses distortion that occurs at the joint surfaces 31e between the connection terminals 31d and the solder H due to external shocks and vibrations.

[0097] The solder H is bonded to the internal wiring 31c of the connection terminal 31d, which is a convex portion protruding from the recess 31g, the bonding surface 31e, and a portion of the end surface 31f, thereby increasing the bonding area with the connection terminal 31d compared to bonding only to the flat bonding surface 31e. Therefore, by bonding the vibrator 22 to the connection terminal 31d, which is a convex portion, with the solder H, the vibrator 22 is bonded more firmly to the substrate 31 than when the vibrator mounting terminal 27a is bonded only to the bonding surface 31e. This makes it possible to prevent the piezoelectric vibrating device 21 from peeling off from the vibrator 22 and the substrate 31.

[0098] [Other embodiments] In the above-described embodiment, the recess 11g of the substrate 11 is recessed in an area including a part of the long side and a part of the short side of the substrate 11, which are the outer edge of the substrate 11 when viewed in the Z direction. However, the recess of the substrate does not have to be in an area including the outer edge of the substrate. The recess may be recessed in any shape in a part of the substrate that does not include the outer edge when viewed in the Z direction.

[0099] In the above-described embodiment, the substrate 11 has a recess 11g for each external connection terminal 11d. However, the substrate does not have to have a recess for each external connection terminal. The substrate may have multiple external connection terminals located in one recess.

[0100] In the above-described embodiment, a predetermined gap G is provided between each side surface 11i of the recess 11g of the substrate 11 and the adjacent end surfaces 11fa, 11fb of the external connection terminal 11d when viewed in the Z direction (see FIG. 6). However, a predetermined gap may be provided between the end surface of the external connection terminal and a part of the adjacent end surface of the recess when viewed in the Z direction.

[0101] In the above-described embodiment, each recess 11g of the substrate 11 has the same thickness from the first mounting surface 11a to the bottom surface 11h. However, each recess of the substrate may have a different thickness from the first mounting surface to the bottom surface.

[0102] In the above embodiment, the substrate 11 has four recesses 11g. However, it is sufficient for the substrate to have at least one recess.

[0103] In the above embodiment, the four end faces 11f including the outer edges of the four external connection terminals 11d are positioned apart from the outer edge of the bottom face 11h so that predetermined gaps G1 and G2 are formed inside the recess 11g as viewed in the Z direction. However, the end faces including the outer edges of the four external connection terminals may be positioned apart from the outer edge of the bottom face of the recess as viewed in the Z direction so that any gap is formed inside the recess.

[0104] In the above embodiment, the internal wiring 11c is electrically connected to the end faces 11f of the four external connection terminals 11d. However, each external connection terminal may have multiple internal wirings exposed in the recess and electrically connected to multiple end faces of the external connection terminal.

[0105] Furthermore, in the above-described embodiment, the vibrator 2 has a through-hole 4c between the frame portion 4 and the vibration portion 5, and cantilevers the vibration portion 5. However, the vibrator may have a configuration that does not have a through-hole between the frame portion and the vibration portion.

[0106] In the above embodiment, the substrate 11 is made of glass. EpoxyIt is made of resin. However, the substrate is glass. Polyimide A glass composite substrate made of resin or the like, a fluororesin substrate, a ceramic substrate, or the like may also be used.

[0107] Furthermore, in the above-described embodiment, the piezoelectric vibration device 1 has a three-layer vibrator 2 in which a piezoelectric diaphragm 3, a first sealing member 7, and a second sealing member 8 are stacked. However, the piezoelectric vibration device may have a vibrator with a three-layer or more structure. The vibrator may also be a four-layer vibrator in which a sensor such as a thermistor is further mounted on the main surface of the first sealing member.

[0108] In the above-described embodiment, the piezoelectric vibration device 1 includes a vibration part 5 in the internal space S of the piezoelectric vibration plate 3. 24 However, the piezoelectric vibration device may also be a so-called H-structure piezoelectric vibration device having a bottom and frame-shaped sidewalls extending perpendicularly to two opposing planes of the bottom. In the H-structure piezoelectric vibration device, a piezoelectric element is located on one plane of the bottom and inside one of the sidewalls. In the H-structure piezoelectric vibration device, an electronic component element is mounted on the other plane of the bottom and inside the other sidewall. In the H-structure piezoelectric vibration device, a first sealing member is bonded to an end of one of the sidewalls, and a second sealing member is bonded to an end of the other sidewall.

[0109] Furthermore, in the above-described embodiment, the piezoelectric diaphragm 23 of the vibrator 22 has a vibrating portion 24 that is separated from the piezoelectric diaphragm 23 so as to surround the pair of excitation electrodes 24a except for one location. In other words, the vibrating portion 24 is configured as a cantilever structure in which it is supported by the piezoelectric diaphragm 23 at one location. However, the vibrating portion may also have a structure in which it is supported by the piezoelectric diaphragm at multiple locations.

[0110] In the above-described embodiments, the vibrators 2 and 22 are joined to the substrates 11 and 31 by solder H. However, it is sufficient that the vibrators are electrically and mechanically connected to the substrates. The vibrators may also be joined by, for example, a conductive adhesive or die attach tape.

[0111] Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiments, and it is possible to appropriately modify the above-described embodiments within the scope of the spirit of the present invention. [Explanation of symbols]

[0112] 1, 21 Piezoelectric vibration device 2, 22 transducer 3, 23 Piezoelectric diaphragm 4 Frame 5, 24 Vibration unit 5a 1st excitation electrode 5b 2nd excitation electrode 6 Connecting part 7, 26 First sealing member 8, 27 Second sealing member 9 Protective materials 10, 30 Integrated circuit element 10a Integrated circuit element mounting terminal 11, 31 board 11a, 31a First mounting surface 11b, 31b Second mounting surface 11c, 31c internal wiring 11d External connection terminal 11e, 31e joint surface 11f, 31f end face 11g, 31g recess 11h, 31h bottom 11i, 31i side 12 Mold section 13, 25 Bonding material 24a Encouragement Shake electric very 2 7a Resonator mounting end child S interior space G1, G2 gap

Claims

1. A piezoelectric vibration device comprising an insulating substrate having a wiring pattern including a plurality of pads on one of a pair of main surfaces, and an external connection terminal on the other main surface parallel to the one main surface, the external connection terminal being electrically connected to the wiring pattern and electrically connected to an external substrate, and having at least a piezoelectric vibrator and an integrated circuit element having an oscillation circuit mounted on the insulating substrate, The insulating substrate is a recessed portion on the other main surface; The external connection terminal is the external connection terminal is configured to have a rectangular shape in a plan view, is located within the recess, and has gaps between four end faces of the external connection terminal and an outer edge of a bottom surface of the recess; A portion of the internal wiring that passes through the inside of the insulating substrate and electrically connects the wiring pattern and the external connection terminal, located on the other main surface side, the insulating substrate is exposed and not covered by a base material of the insulating substrate, and is connected to an end face of the external connection terminal and protrudes from the end face toward a side face of the recess, and is covered by a bonding material that bonds the external connection terminal to the external substrate. Piezoelectric vibration device.

2. 2. The piezoelectric vibration device according to claim 1, The external connection terminal is the other main surface is positioned in the recess at a predetermined distance from the outer edge of the recess, as viewed in a direction perpendicular to the other main surface; Piezoelectric vibration device.

3. 3. The piezoelectric vibration device according to claim 1, a thickness from the one main surface to a connection surface of the external connection terminal that is electrically connected to the external substrate is equal to or less than a thickness from the one main surface to the other main surface; Piezoelectric vibration device.

4. 4. The piezoelectric vibration device according to claim 1, The insulating substrate is a portion of one of the main surfaces including at least one of the piezoelectric vibrator and the integrated circuit element is covered with a resin; Piezoelectric vibration device.

5. 5. The piezoelectric vibration device according to claim 1, The piezoelectric vibrator and the integrated circuit element are are located on the same mounting surface of the insulating substrate; Piezoelectric vibration device.

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