piezoelectric oscillator

Abstract

The piezoelectric vibrator (1) of the present invention comprises a piezoelectric vibrating element (10), a base component (30), and a cover component (40). The cover component (40) has a top wall portion (41) and a side wall portion (42). The side wall portion (42) has a facing surface (43B) opposite to the base component (30). The base component (30) is provided with a power supply electrode for connecting the piezoelectric vibrating element (10) and a grounding electrode for grounding. The grounding electrode is electrically connected to the cover component (40) via a connecting component (50). The conductive adhesive comprises a resin-based adhesive (51) and a conductive filler (52). The particle size R of the conductive filler (52) satisfies the following relationship: 4μm≤R≤15μm.

Description

Technical Field

[0001] This invention relates to piezoelectric vibrators. Background Technology

[0002] Oscillators are used in various electronic devices such as mobile communication terminals, communication base stations, and home appliances for purposes such as timing devices, sensors, and oscillators. With the increasing functionality of electronic devices, there is a need for inexpensive and high-performance vibration components.

[0003] Patent Document 1 discloses a quartz oscillator that bonds a base component and a metal cover component together via a conductive adhesive. The conductive adhesive electrically connects the cover component to the grounding electrode of the base component, thereby suppressing noise caused by the entry and exit of electromagnetic waves.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2015-220749

[0005] However, in the quartz oscillator described in Patent Document 1, if the conductive filler is too small, the cover component may fail to ground due to poor contact between the conductive filler and the cover component. Conversely, if the conductive filler is too large, the sealing performance may decrease due to increased thickness of the conductive adhesive. Summary of the Invention

[0006] The present invention was made in view of the following circumstances, and the object of the present invention is to provide a piezoelectric vibrator capable of suppressing noise and suppressing the generation of defective products.

[0007] One aspect of the piezoelectric vibrator of the present invention comprises: a piezoelectric vibrating element; a base member on which the piezoelectric vibrating element is mounted; and a cover member made of conductive material, which is joined to the base member by a bonding member of conductive adhesive, and forms an internal space between the cover member and the base member in which the piezoelectric vibrating element is disposed. The cover member has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base member. The side wall portion has a facing surface opposite to the base member. The base member is provided with a power supply electrode for connecting the piezoelectric vibrating element and a grounding electrode for grounding. The grounding electrode is electrically connected to the cover member via the bonding member. The conductive adhesive comprises a resin-based adhesive and a conductive filler dispersed in the resin-based adhesive. The particle size R of the conductive filler satisfies the following relationship: 4μm≤R≤15μm.

[0008] One aspect of the piezoelectric vibrator of the present invention comprises: a piezoelectric vibrating element; a base member on which the piezoelectric vibrating element is mounted; and a cover member of conductive material joined to the base member by a bonding member of conductive adhesive, forming an internal space between the cover member and the base member in which the piezoelectric vibrating element is disposed. The cover member has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base member. The side wall portion has a facing surface opposite to the base member. In the base member, a power supply electrode for connecting the piezoelectric vibrating element and a grounding electrode for grounding are provided. The grounding electrode is electrically connected to the cover member via the bonding member. The conductive adhesive has a resin-based adhesive and a conductive filler dispersed in the resin-based adhesive. In the base member, a protective film of insulating material is provided, at least covering the area of ​​the power supply electrode facing the facing surface. The protective film is in contact with the bonding member. The gap G1 between the grounding electrode and the facing surface and the gap G2 between the protective film and the facing surface satisfy the following relationship: 0 ≤ G2 - G1 ≤ 13 μm.

[0009] According to the present invention, a piezoelectric vibrator capable of suppressing noise and suppressing the generation of defective products can be provided. Attached Figure Description

[0010] Figure 1 This is an exploded perspective view schematically illustrating the structure of a quartz oscillator in an embodiment.

[0011] Figure 2 This is a top view schematically illustrating the structure of a quartz oscillator in an embodiment.

[0012] Figure 3 This is a cross-sectional view schematically illustrating the structure of a quartz oscillator in an embodiment.

[0013] Figure 4 It is a top view schematically showing the structure of the base components and the quartz resonator.

[0014] Figure 5 It is an enlarged cross-sectional view of a quartz oscillator including the grounding electrode.

[0015] Figure 6 It is an enlarged cross-sectional view of a quartz oscillator including the electrodes for power supply.

[0016] Figure 7 This is a table showing the grounding failure rate and leakage failure rate when the particle size R is varied.

[0017] Figure 8 This is a table showing the leakage failure rate when gaps G1 and G2 are varied. Detailed Implementation

[0018] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The drawings for each embodiment are illustrative, and the dimensions and shapes of the parts are schematic and should not be construed as limiting the technical scope of the present invention to these embodiments.

[0019] Reference Figures 1-4 The structure of the quartz oscillator 1 according to an embodiment of the present invention will be described. Figure 1 This is an exploded perspective view schematically illustrating the structure of a quartz oscillator in an embodiment. Figure 2 This is a top view schematically illustrating the structure of a quartz oscillator in an embodiment. Figure 3 This is a cross-sectional view schematically illustrating the structure of a quartz oscillator in an embodiment. Figure 4 This is a schematic top view showing the structure of the base components and the quartz resonator. It should be noted that... Figure 3 It is along Figure 2 The cross-sectional view of the quartz oscillator 1 along line III-III shown.

[0020] In the various accompanying figures, to clarify the relationships between them and aid in understanding the positional relationships of the components, an orthogonal coordinate system consisting of the X-axis, Y′-axis, and Z′-axis is sometimes included for convenience. In each figure, the X-axis, Y′-axis, and Z′-axis correspond to each other. The X-axis, Y′-axis, and Z′-axis are respectively related to the crystallographic axes of the quartz plate 11, as described later. The X-axis corresponds to the electrical axis (polarity axis) of the quartz crystal, the Y-axis corresponds to the mechanical axis of the quartz crystal, and the Z-axis corresponds to the optical axis of the quartz crystal. The Y′-axis and Z′-axis are the axes obtained by rotating the Y-axis and Z-axis around the X-axis from the Y-axis to the Z-axis by 35 degrees 15 minutes ± 1 minute 30 seconds.

[0021] In the following explanation, the direction parallel to the X-axis will be called the "X-axis direction," the direction parallel to the Y′-axis will be called the "Y′-axis direction," and the direction parallel to the Z′-axis will be called the "Z′-axis direction." Furthermore, the direction of the arrowheads for the X, Y′, and Z′ axes will be called "+" (positive), and the direction opposite to the arrowheads will be called "-" (negative). For convenience, the +Y′-axis direction will be described as upwards and the -Y′-axis direction as downwards, but the vertical orientation of the quartz oscillator 1 is not strictly defined.

[0022] The quartz oscillator 1 includes a quartz resonant element 10, a base component 30, a cover component 40, and a connecting component 50. The quartz resonant element 10 is disposed between the base component 30 and the cover component 40. The base component 30 and the cover component 40 constitute a holder for housing the quartz resonant element 10 and overlap along the Y′ axis. The quartz resonant element 10 is mounted on the base component 30.

[0023] First, the quartz resonating element 10 will be explained.

[0024] The quartz vibrating element 10 is a piezoelectric vibrating element that converts quartz into electrical energy and mechanical energy by vibrating quartz through the piezoelectric effect. The quartz vibrating element 10 includes a thin quartz plate 11, a first excitation electrode 14a and a second excitation electrode 14b forming a pair of excitation electrodes, a first lead-out electrode 15a and a second lead-out electrode 15b forming a pair of lead-out electrodes, and a first connecting electrode 16a and a second connecting electrode 16b forming a pair of connecting electrodes.

[0025] The quartz plate 11 has an upper surface 11A and a lower surface 11B that are opposite to each other. The upper surface 11A is located on the opposite side of the base member 30, that is, on the side opposite to the top wall portion 41 of the cover member 40 described later. The lower surface 11B is located on the side opposite to the base member 30.

[0026] Quartz plate 11 is, for example, an AT-cut quartz crystal. The AT-cut quartz plate 11 is formed such that, in an orthogonal coordinate system composed of intersecting X-axis, Y′-axis, and Z′-axis, the plane parallel to the plane defined by the X-axis and Z′-axis (hereinafter referred to as the "XZ′ plane"; the same applies to the plane defined by the other axes) is the principal plane, and the direction parallel to the Y′-axis is the thickness.

[0027] The quartz resonator 10 using an AT-cut quartz plate 11 exhibits high frequency stability over a wide temperature range. In the AT-cut quartz resonator 10, the thickness shear vibration mode is used as the primary vibration. The quartz plate 11 can also be cut with different cuts besides AT. For example, BT cut, GT cut, SC cut, etc., can be used. Alternatively, the quartz resonator can also be a tuning fork type quartz resonator using a quartz plate with a cut angle known as a Z-plate.

[0028] As an example, the quartz plate 11 is a flat plate having a long side direction extending parallel to the X-axis, a short side direction extending parallel to the Z′-axis, and a thickness direction extending parallel to the Y′-axis. When viewed from above, the upper surface 11A of the quartz plate 11 has a rectangular planar shape.

[0029] The quartz plate 11 is not limited to a flat plate shape; it can also be a mesa-shaped structure or an inverted mesa-shaped structure. In this case, the quartz plate 11 can also be a conical shape with continuously varying thickness, a stepped shape with discontinuously varying thickness, a convex shape with continuously varying thickness, or a slope shape with discontinuously varying thickness.

[0030] The first excitation electrode 14a is disposed on the upper surface 11A of the quartz plate 11, and the second excitation electrode 14b is disposed on the lower surface 11B of the quartz plate 11. The first excitation electrode 14a and the second excitation electrode 14b are positioned opposite each other across the quartz plate 11. When viewed from above on the upper surface 11A of the quartz plate 11, the first excitation electrode 14a and the second excitation electrode 14b are both rectangular in shape and are configured to approximately overlap each other.

[0031] The first lead-out electrode 15a is disposed on the upper surface 11A of the quartz plate 11, and the second lead-out electrode 15b is disposed on the lower surface 11B of the quartz plate 11. The first lead-out electrode 15a electrically connects the first excitation electrode 14a and the first connecting electrode 16a. The second lead-out electrode 15b electrically connects the second excitation electrode 14b and the second connecting electrode 16b.

[0032] The first connecting electrode 16a and the second connecting electrode 16b are electrodes used to electrically connect the first excitation electrode 14a and the second excitation electrode 14b to the base component 30, respectively, and are disposed on the lower surface 11B of the quartz plate 11.

[0033] The excitation electrode, lead-out electrode, and connecting electrode are, for example, a laminate consisting of a substrate layer that adheres well to the quartz plate 11 and a chemically stable outermost layer. The materials constituting the excitation electrode, lead-out electrode, and connecting electrode are preferably selected from metallic materials such as chromium (Cr), gold (Au), titanium (Ti), molybdenum (Mo), aluminum (Al), nickel (Ni), indium (In), palladium (Pd), silver (Ag), copper (Cu), tin (Sn), and iron (Fe). The excitation electrode, lead-out electrode, and connecting electrode may also contain conductive ceramics, conductive resins, semiconductors, etc.

[0034] Next, the base component 30 will be described.

[0035] The base component 30 includes a flat substrate 31, a first electrode pad 33a and a second electrode pad 33b forming a pair of electrode pads, an upper surface electrode 33c, a first side electrode 34a, a second side electrode 34b, a third side electrode 34c, a fourth side electrode 34d, a first external electrode 35a, a second external electrode 35b, a third external electrode 35c, a fourth external electrode 35d, and a protective film 39.

[0036] The substrate 31 has an upper surface 31A and a lower surface 31B that are opposite each other. The upper surface 31A and the lower surface 31B correspond to a pair of main surfaces of the substrate 31. The upper surface 31A is located on the side opposite to the quartz resonator 10 and the cover member 40, for example, when the quartz resonator 1 is mounted on an external circuit board, and the lower surface 31B is located on the side opposite to the circuit board. The substrate 31 is, for example, a sintered material such as insulating ceramic (alumina), but it can also be made of quartz, silicon, etc.

[0037] When viewed from above on the upper surface 31A, the substrate 31 has a pair of long sides extending along the X-axis and opposite each other in the Z′-axis direction, and a pair of short sides extending along the Z′-axis and opposite each other in the X-axis direction. Fan-shaped recesses are provided at the four corners of the substrate 31. These recesses are formed by cutting through a through-hole extending from the upper surface 31A to the lower surface 31B through the substrate 31.

[0038] First electrode pad 33a and second electrode pad 33b are disposed on the upper surface 31A of the substrate 31. The first electrode pad 33a and second electrode pad 33b are terminals for electrically connecting the quartz resonator 10 to the base component 30. When viewed from above on the upper surface 31A of the substrate 31, the first electrode pad 33a and second electrode pad 33b are surrounded by the bonding component 50.

[0039] The upper surface electrode 33c is an electrode electrically connected to the cover member 40. The upper surface electrode 33c is disposed at the corner of the base member 30 on the +X axis direction side and the -Z′ axis direction side, and is located on the outermost surface of the base member 30 on the cover member 40 side.

[0040] First side electrodes 34a to fourth side electrodes 34d are disposed on the side portions connecting the outermost edge of the upper surface 31A and the outermost edge of the lower surface 31B of the base member 30. Specifically, they are disposed from the end of the recess at the corner of the base 31 on the upper surface 31A side to the end of the recess on the lower surface 31B side, covering the recess of the base 31. The first side electrodes 34a to fourth side electrodes 34d are respectively equivalent to castle-type electrodes. The first side electrode 34a is disposed in the recess, wherein the recess is disposed at the corner of the base member 30 on the -X-axis direction side and the +Z′-axis direction side. The second side electrode 34b is disposed in the recess, wherein the recess is disposed at the corner of the base member 30 on the +X-axis direction side and the -Z′-axis direction side. The third side electrode 34c is disposed in the recess, wherein the recess is disposed at the corner of the base member 30 on the +X-axis direction side and the +Z′-axis direction side. The fourth side electrode 34d is disposed in the recess, wherein the recess is disposed at the corner of the base member 30 on the -X axis direction side and the -Z′ axis direction side.

[0041] The first side electrode 34a is electrically connected to the first electrode pad 33a via a wiring electrode 37a disposed on the upper surface 31A, and the second side electrode 34b is electrically connected to the second electrode pad 33b via a wiring electrode 37b disposed on the upper surface 31A. The third side electrode 34c is continuously disposed from the upper surface electrode 33c and electrically connected to the upper surface electrode 33c. The first side electrode 34a, the first electrode pad 33a, and the wiring electrode 37a connecting these components correspond to power supply electrodes for connecting the quartz resonator 10. Similarly, the second side electrode 34b, the second electrode pad 33b, and the wiring electrode 37b connecting these components also correspond to power supply electrodes. The third side electrode 34c and the upper surface electrode 33c correspond to grounding electrodes for grounding the cover component 40.

[0042] The power supply electrode and the grounding electrode are, for example, laminates consisting of a base layer that adheres well to the substrate 31 and an outermost layer that has good chemical stability. The materials constituting the power supply electrode and the grounding electrode are preferably selected from metallic materials such as chromium (Cr), gold (Au), titanium (Ti), molybdenum (Mo), aluminum (Al), nickel (Ni), indium (In), palladium (Pd), silver (Ag), copper (Cu), tin (Sn), and iron (Fe). The power supply electrode and the grounding electrode may also contain conductive ceramics, conductive resins, semiconductors, etc.

[0043] The first external electrode 35a to the fourth external electrode 35d are electrodes used to mount the quartz oscillator 1 to an external circuit board using solder or the like. The first external electrode 35a to the fourth external electrode 35d are disposed on the lower surface 31B of the substrate 31. The first external electrode 35a is disposed at a corner of the base member 30 on the -X-axis and +Z′-axis sides, and is electrically connected to the first side electrode 34a. The first external electrode 35a is disposed at a corner of the base member 30 on the +X-axis and -Z′-axis sides, and is electrically connected to the second side electrode 34b. The third external electrode 35c is disposed at a corner of the base member 30 on the +X-axis and +Z′-axis sides, and is electrically connected to the third side electrode 34c. The fourth external electrode 35d is disposed at a corner of the base member 30 on the -X-axis and -Z′-axis sides, and is electrically connected to the fourth side electrode 34d. The first external electrode 35a and the second external electrode 35b are used to supply electrical signals to a pair of power supply electrodes. The third external electrode 35c is used to ground the grounding electrode. The fourth external electrode 35d is a virtual electrode that does not input or output electrical signals, etc. The fourth external electrode 35d may also be used together with the third external electrode 35c to ground the cover component 40, or it may be omitted.

[0044] A protective film 39 is disposed on the side opposite to the cover member 40 of the base member 30 and in contact with the engaging member 50. The protective film 39 is made of an insulating material. The protective film 39 covers a portion of the power supply electrode (the area opposite the opposing surface 43B of the cover member 40), electrically insulating the power supply electrode from the cover member 40. Specifically, the protective film 39 covers at least a portion of the wiring electrode 37a connecting the first side electrode 34a and the first electrode pad 33a, and covers at least a portion of the wiring electrode 37b connecting the second side electrode 34b and the second electrode pad 33b. The protective film 39 is disposed in the area outside the upper surface electrode 33c, which protrudes from the protective film 39. The protective film 39 is, for example, a solder resist.

[0045] Furthermore, the conductivity of the bonding member 50 described later is sufficiently anisotropic. If the conductivity along the direction of the upper surface 31A of the substrate 31 is sufficiently low, the protective film 39 can be omitted. This is because, in this case, even if the bonding member 50 comes into contact with the power supply electrode, it is not easy to generate a short circuit through the bonding member 50 of the quartz resonating element 10 and the cover member 40.

[0046] The base component 30 includes a first conductive retaining component 36a and a second conductive retaining component 36b, which constitute a pair of conductive retaining components. The first conductive retaining component 36a and the second conductive retaining component 36b are spaced apart from the base component 30 and the cover component 40 to retain the quartz resonator 10. The first conductive retaining component 36a and the second conductive retaining component 36b electrically connect the quartz resonator 10 and the base component 30. Specifically, the first conductive retaining component 36a electrically connects the first electrode pad 33a and the first connecting electrode 16a, and the second conductive retaining component 36b electrically connects the second electrode pad 33b and the second connecting electrode 16b. The first conductive retaining component 36a and the second conductive retaining component 36b are, for example, cured products of conductive adhesives including thermosetting resins, photocurable resins, etc.

[0047] Next, the cover component 40 will be described.

[0048] The cover component 40 is joined to the base component 30. An internal space for accommodating the quartz resonator 10 is formed between the cover component 40 and the base component 30. The cover component 40 has a recess 49 that opens to one side of the base component 30, and in this embodiment, the internal space corresponds to the space inside the recess 49. The recess 49 is liquid-tightly sealed. The cover component 40 is made of a conductive material, and more preferably a metal material with high airtightness. By making the cover component 40 of a conductive material, the cover component 40 is given an electromagnetic shielding function that reduces the entry and exit of electromagnetic waves into the internal space. From the viewpoint of suppressing the generation of thermal stress, the material of the cover component 40 is preferably a material with a thermal expansion coefficient close to that of the base 31, such as an Fe-Ni-Co alloy with a thermal expansion coefficient near room temperature that is consistent with that of glass and ceramics over a wide temperature range.

[0049] The cover member 40 has a flat top wall portion 41 and a side wall portion 42 connected to the outer edge of the top wall portion 41. The top wall portion 41 extends along the upper surface 31A of the base 31 and is positioned opposite the base member 30 in the height direction, separated by the quartz resonator 10. The side wall portion 42 extends from the top wall portion 41 toward the base member 30 and surrounds the quartz resonator 10 in a direction parallel to the upper surface 31A of the base 31. The cover member 40 may also have a flange portion that connects to the front end of the side wall portion 42 on the base member 30 side and extends outward along the upper surface 31A of the base 31.

[0050] The cover member 40 has an inner surface located on one side of the recess 49 and an outer surface exposed to the outside on the opposite side of the recess 49. The inner surface is the side of the top wall portion 41 and the side wall portion 42 opposite to the quartz resonator 10, and the outer surface is the side of the top wall portion 41 and the side wall portion 42 opposite to the side of the quartz resonator 10. The cover member 40 also has a facing surface 43B opposite to the base member 30. The facing surface 43B is a surface that extends along the upper surface 31A of the base 31 at the front end of the side wall portion 42 of the base member 30. The area of ​​the facing surface 43B can be expanded by providing a flange portion.

[0051] The planar shape of the cover member 40 when viewed from the normal direction of the main surface is, for example, approximately rectangular. The planar shape of the cover member 40 is not limited to the above shape, and may also be a polygonal shape, a circular shape, an elliptical shape, or a combination of these shapes.

[0052] Next, the joining component 50 will be described.

[0053] The connecting member 50 connects the base member 30 and the cover member 40. Specifically, the connecting member 50 connects the protective film 39 and the opposing surface 43B, and also connects the upper surface electrode 33c and the opposing surface 43B. In addition, the connecting member 50 seals the recess 49 corresponding to the internal space. Specifically, the connecting member 50 is provided around the entire circumference of the outer edge of each of the base member 30 and the cover member 40, forming a rectangular frame to surround the quartz resonator 10.

[0054] The bonding member 50 is a conductive adhesive that electrically connects the grounding electrode and the cover member 40. The conductivity of the bonding member 50 is anisotropic. Specifically, in the region between the upper surface electrode 33c and the opposing surface 43B, the bonding member 50 along the direction intersecting the upper surface 31A of the substrate 31 has a lower resistance, and the upper surface electrode 33c and the opposing surface 43B are electrically connected via the bonding member 50. On the other hand, the bonding member 50 along the upper surface 31A of the substrate 31 has a higher resistance, and even when the bonding member 50 is in contact with the power supply electrode, the power supply electrode is electrically insulated from the cover member 40.

[0055] Next, refer to Figure 5 and Figure 6 A more detailed description of the structure of the joint portion via the joint member 50 will be provided. Figure 5 It is an enlarged cross-sectional view of a quartz oscillator including the grounding electrode. Figure 6 It is an enlarged cross-sectional view of a quartz oscillator including the electrodes for power supply.

[0056] The conductive adhesive of the bonding component 50 has a resin-based adhesive 51, a plurality of conductive fillers 52 dispersed in the resin-based adhesive 51, and a plurality of insulating fillers 53 dispersed in the resin-based adhesive 51.

[0057] The resin-based adhesive 51 is, for example, an epoxy-based thermosetting resin. The resin-based adhesive 51 may also be an epoxy-based, vinyl-based, acrylic-based, polyurethane-based, imide-based, or silicone-based thermosetting resin. The resin-based adhesive 51 may also include a photocurable resin.

[0058] The conductive filler 52 is, for example, a spherical filler with a spherical resin core covered by a metal film. The conductive filler 52 can be deformed, and the conductive filler 52, held between the upper surface electrode 33c and the opposing surface 43B, is deformed into an ellipsoidal shape. With deformation, the conductive filler 52 reliably contacts both the upper surface electrode 33c and the opposing surface 43B. Thus, the upper surface electrode 33c and the opposing surface 43B are electrically connected via the conductive filler 52. Furthermore, with deformation, the contact area between the conductive filler 52 and the upper surface electrode 33c, and the contact area between the conductive filler 52 and the opposing surface 43B, increases. Thus, the resistance between the conductive filler 52 and the upper surface electrode 33c decreases. The resin core material is, for example, a styrene-based resin or an acrylic resin. Therefore, the elastic modulus of the conductive filler 52 can be appropriately designed. The metal film material is, for example, Ni. Therefore, it is possible to suppress the metal film from peeling off from the resin core and to suppress the increase in resistance.

[0059] Furthermore, the resin core is not limited to styrene-based or acrylic-based resins, as long as it is deformable. Additionally, the metal film is not limited to Ni; it can also be provided by metal materials such as Au, Ag, Cu, Al, and Ti. The metal film can also be a multilayer film composed of multiple metal layers. The conductive filler 52 can also be a spherical structure made of conductive materials such as Cu, Ni, C, and Si.

[0060] The insulating filler 53 adjusts the viscosity of the conductive adhesive before curing, suppressing contact with the power supply electrodes due to unnecessary wetting and diffusion of the conductive adhesive before curing. The material of the insulating filler 53 is, for example, spherical silica. The material of the insulating filler 53 is not limited to the above-mentioned materials; it can also be organic compounds such as organosilicon, polyurethane, imide, epoxy resin, ethylene, amine, phenol, amino, acrylic acid, and styrene, or inorganic compounds such as titanium dioxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, aluminum oxide, boron nitride, aluminum nitride, glass fiber, and graphite.

[0061] The ratio of the volume of the conductive filler 52 to the total volume of the conductive adhesive of the bonding member 50 (hereinafter, "volume ratio") is 3 vol% or more and 18 vol% or less.

[0062] When the volume ratio is less than 3 vol%, there is a situation where there is no conductive filler 52 in the area between the upper surface electrode 33c and the opposing surface 43B, and an electrical connection between the upper surface electrode 33c and the opposing surface 43B cannot be obtained. That is, when the volume ratio is 3 vol% or more, the production rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0063] When the volume ratio is greater than 18 vol%, the conductive fillers 52 are close to or in contact with each other, and the resistance of the joint member 50 along the upper surface 31A of the substrate 31 decreases. That is, when the volume ratio is less than 18 vol%, the rate of defective products with short circuits between the quartz vibrating element 10 and the cover member 40 can be reduced.

[0064] Furthermore, from the viewpoint of reducing the rate of defective products where the cover component 40 cannot be grounded, it is preferable that the volume ratio is 7 vol% or more. Additionally, from the viewpoint of reducing the rate of defective products where the quartz vibrating element 10 and the cover component 40 are short-circuited, it is even more preferable that the volume ratio is 10 vol% or less.

[0065] If the conductive filler 52 is assumed to be a perfect sphere, its diameter (hereinafter, "particle size R") satisfies the relationship 4μm≤R≤15μm.

[0066] Due to the undulations of the cover member 40, the gap G1 between the upper surface electrode 33c and the opposing surface 43B varies by an average of approximately 3.8 μm. Therefore, when R < 4 μm, there is a possibility that the conductive filler 52 will not be in contact with at least one of the upper surface electrode 33c and the opposing surface 43B. That is, when 4 μm ≤ R, the rate of defective products where the cover member 40 cannot be grounded can be reduced. Furthermore, since the maximum variation of the gap G1 caused by the undulations of the cover member 40 is approximately 6 μm, it is even more preferable to satisfy 6 μm ≤ R.

[0067] Since the conductive filler 52 acts as a separator, when R < 15 μm, the thickness of the joint component 50 in the area between the upper surface electrode 33c and the opposing surface 43B increases, resulting in a decrease in sealing performance. That is, when R ≤ 15 μm, the rate of defective products with frequency variations due to poor leakage can be reduced.

[0068] Furthermore, the particle size R is the arithmetic mean particle size calculated based on the particle size distribution of the resin core of the conductive filler 52 obtained by the Coulter counting method. Since the thickness of the metal film of the conductive filler 52 is sufficiently small compared to the particle size of the resin core, the particle size of the resin core can be considered as the particle size R of the conductive filler 52. Here, as an example, the thickness of the metal film of the conductive filler 52 is 10 nm or more and 500 nm or less. When the thickness of the metal film is less than 10 nm, the resistance of the conductive filler 52 increases. When the thickness of the metal film is greater than 500 nm, the metal film may hinder the deformation of the conductive filler 52, or the metal film may peel off from the resin core. That is, when the thickness of the metal film is 10 nm or more and 500 nm or less, the production rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0069] The width W of the short side of the opposing surface 43B and the particle size R of the conductive filler 52 satisfy the following relationship: 4μm≤R≤W / 2.

[0070] To establish conductivity between the grounding electrode and the cover component 40, pressure is applied to the conductive filler 52, which is held between the upper surface electrode 33c and the opposing surface 43B. At this time, when W / 2 < R, the conductive filler 52 may be squeezed out from the area between the upper surface electrode 33c and the opposing surface 43B. That is, when R ≤ W / 2, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0071] When 4μm≤R, the rate of defective products where the cover component 40 cannot be grounded can be reduced as described above.

[0072] The diameter (hereinafter referred to as "particle size r") of the insulating filler 53 is assumed to be a perfect sphere, and the particle size R of the conductive filler 52 satisfies the relationship r < R.

[0073] When R ≤ r, the insulating filler 53 acts as an insulator, hindering the deformation of the conductive filler 52. For example, if the elastic modulus of the insulating filler 53 is greater than that of the conductive filler 52, and R = r, the deformation of the conductive filler 52 is hindered by the insulating filler 53. Furthermore, even if the elastic modulus of the insulating filler 53 is less than that of the conductive filler 52, if R << r, the deformation of the conductive filler 52 is hindered by the insulating filler 53. Therefore, when r < R, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0074] In addition, the particle size r is the median diameter D50 calculated based on the particle size distribution obtained by the Microtrack method.

[0075] The particle size R and particle size r satisfy the relationship R / 20≤r≤R×8 / 10.

[0076] When r < R / 20, insulating filler 53 intrudes between conductive filler 52 and upper surface electrode 33c, thus hindering contact between conductive filler 52 and upper surface electrode 33c. Similarly, contact between conductive filler 52 and opposing surface 43B is hindered. That is, when R / 20 ≤ r, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0077] When R×8 / 10 < r, the insulating filler 53 in the area between the upper surface electrode 33c and the opposing surface 43B acts as a separator, hindering the deformation of the conductive filler 52. That is, when r ≤ R×8 / 10, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0078] Furthermore, from the viewpoint of reducing the generation rate of defective products where the cover component 40 cannot be grounded, it is preferable that the particle size R and particle size r further satisfy the relationship R / 10 ≤ r. Additionally, it is preferable that r ≤ R / 2.

[0079] The gap G1 between the upper surface electrode 33c and the opposing surface 43B, the gap G2 between the protective film 39 and the opposing surface 43B, and the particle size R of the conductive filler 52 satisfy the relationship G1 < R < G2.

[0080] When R ≤ G1, there is a situation where the conductive filler 52 does not contact at least one of the upper surface electrode 33c and the opposing surface 43B. That is, when G1 < R, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0081] When G2 ≤ ​​R, the conductive filler 52 sandwiched between the protective film 39 and the opposing surface 43B deforms. Furthermore, during the deformation of the conductive filler 52 sandwiched between the upper surface electrode 33c and the opposing surface 43B, a portion of the conductive filler 52 is extruded from the area between the protective film 39 and the opposing surface 43B. Consequently, the conductive fillers 52 approach each other in an undesirable area, resulting in a decrease in the resistance of the bonding member 50 along the direction of the upper surface 31A of the substrate 31. That is, when R < G2, the rate of defective products with short circuits between the quartz resonator 10 and the cover member 40 can be reduced.

[0082] Gap G1 and gap G2 satisfy the relationship 0 ≤ G2 - G1 ≤ 13 μm. When G2 - G1 < 0, i.e., G2 < G1, the conductive filler 52 located in the area between the protective film 39 and the opposing surface 43B acts as an insulator, preventing sufficient deformation of the conductive filler 52 in the area between the upper surface electrode 33c and the opposing surface 43B. That is, when 0 ≤ G2 - G1, the rate of defective products where the cover component 40 cannot be grounded can be reduced.

[0083] When 13μm < G2-G1, the sealing performance decreases as the film thickness of the mating member 50 in the area between the protective film 39 and the opposing surface 43B increases. That is, when G2-G1 ≤ 13μm, the rate of defective products with varying frequency due to poor leakage can be reduced.

[0084] The gap G2 satisfies the relationship 2μm≤G2≤20μm.

[0085] The gap G2 is limited by the particle size R. Therefore, to reduce the gap G2, the particle size R needs to be reduced. When G2 < 2 μm, due to the small particle size R, there is a possibility that the conductive filler 52 will not contact at least one of the upper surface electrode 33c and the opposing surface 43B due to the variation in gap G1 caused by the undulation of the cover member 40. That is, when 2 μm ≤ G2, the rate of defective products that cannot be grounded can be reduced.

[0086] When G2 < 20 μm, the sealing performance decreases as the thickness of the mating member 50 in the area between the protective film 39 and the opposing surface 43B increases. That is, when G2 ≤ ​​20 μm, the rate of defective products with varying frequency due to poor leakage can be reduced.

[0087] Next, refer to Figure 7 and Figure 8 The embodiments and comparative examples will be described. Figure 7 This is a table showing the grounding failure rate when the width W and particle size R are varied. Figure 8 This is a table showing the grounding failure rate when the particle size R and particle size r are varied.

[0088] Figure 7 The quartz oscillators in Examples 1-3 and Comparative Examples 1 and 2 are quartz oscillators 1 of this embodiment, and are structures in which the addition rate of conductive filler 52 is kept constant and the particle size R is varied. "Addition rate of conductive filler 52" is the ratio of the weight of conductive filler 52 to the total weight of conductive adhesive.

[0089] (Comparative Example 1)

[0090] R = 3.0 μm, and the addition rate of conductive filler 52 is 10 wt%.

[0091] (Example 1)

[0092] R = 5 μm, and the addition rate of conductive filler 52 is 10 wt%.

[0093] (Example 2)

[0094] R = 10 μm, and the addition rate of conductive filler 52 is 10 wt%.

[0095] (Example 3)

[0096] R = 15 μm, and the addition rate of conductive filler 52 is 10 wt%.

[0097] (Comparative Example 2)

[0098] R = 20 μm, and the addition rate of conductive filler 52 is 10 wt%.

[0099] In each quartz oscillator 1, the rates of defective products (hereinafter, "grounding failure rate") due to non-electrical connection between the cover component 40 and the power supply electrode, and the rates of defective products (hereinafter, "leakage failure rate") due to frequency variation caused by leakage failure were measured. Each measurement sample consisted of 20 samples. In determining the grounding failure rate, samples with a resistance of 10Ω or less between the grounding electrode and the cover component 40 were considered acceptable, while those with a resistance greater than 10Ω were considered unacceptable. Samples with a grounding failure rate of 5% or less were recorded as 0, and those with a grounding failure rate greater than 5% were recorded as ×. In determining the leakage failure rate, samples where Galden (registered trademark, manufactured by Solvay) did not penetrate the interior even after immersion and depressurization were considered acceptable, while samples where Galden penetrated the interior after immersion and depressurization were considered unacceptable. Samples with a leakage failure rate of 5% or less were recorded as 0, and those with a leakage failure rate greater than 5% were recorded as ×.

[0100] In Comparative Example 1, which satisfies R < 4 μm, although the leakage failure rate was low, the grounding failure rate was high, and the generation rate of defective products could not be sufficiently reduced. In Comparative Example 2, which satisfies 15 μm < R, although the grounding failure rate was low, the leakage failure rate was high, and the generation rate of defective products could not be sufficiently reduced. In Examples 1 to 3, which satisfy 4 μm ≤ R ≤ 15 μm, both the grounding failure rate and the leakage failure rate were low, and the generation of defective products could be suppressed.

[0101] Figure 8 The quartz oscillators in Examples 4 to 6 and Comparative Examples 3 and 4 are quartz oscillators 1 of this embodiment, and are structures with the gaps G1 and G2 changed.

[0102] (Example 4)

[0103] G1=15μm, G2=20μm, G2-G1=5μm

[0104] (Example 5)

[0105] G1=10μm, G2=20μm, G2-G1=10μm

[0106] (Example 6)

[0107] G1=7μm, G2=20μm, G2-G1=13μm

[0108] (Comparative Example 3)

[0109] G1=7μm, G2=22μm, G2-G1=15μm

[0110] (Comparative Example 4)

[0111] G1 = 15 μm, G2 = 28 μm, G2 - G1 = 13 μm

[0112] In each of the quartz oscillators 1, the leakage defect rate was measured. The number of measurement samples for each was 20. In the determination of the leakage defect rate, a sample in which Galden did not penetrate inside even when immersed in Galden and decompressed was judged as a qualified product, and a sample in which Galden penetrated inside when immersed in Galden and decompressed was judged as a non - qualified product. Samples with a leakage defect rate of 5% or less were marked as 〇, and samples with a leakage defect rate greater than 5% were marked as ×.

[0113] In Comparative Example 3 where 13 μm < G2 - G1 is satisfied, the leakage defect rate is high, and the generation rate of non - qualified products cannot be sufficiently reduced. In Comparative Example 4 where 0 ≤ G2 - G1 ≤ 13 μm is satisfied but 20 μm < G2 is satisfied, the leakage defect rate is high, and the generation rate of non - qualified products cannot be sufficiently reduced.

[0114] As described above, in the present embodiment, the relationship of 4 μm ≤ R ≤ 15 μm is satisfied.

[0115] Thereby, it is possible to make the conductive filler 52 contact both the upper surface electrode 33c and the opposing surface 43B, and reduce the thickness of the bonding member 50. Therefore, it is possible to reduce the generation rate of non - qualified products where the lid member 40 cannot be grounded, and also reduce the generation rate of non - qualified products with frequency variation due to leakage defects.

[0116] In another embodiment, the relationship of 0 ≤ G2 - G1 ≤ 13 μm is satisfied.

[0117] Thereby, it is possible to make the conductive filler 52 contact both the upper surface electrode 33c and the opposing surface 43B, and reduce the thickness of the bonding member 50. Therefore, it is possible to reduce the generation rate of non - qualified products where the lid member 40 cannot be grounded, and also reduce the generation rate of non - qualified products with frequency variation due to leakage defects.

[0118] Hereinafter, a part or all of the embodiments of the present invention are noted and their effects are described. In addition, the present invention is not limited to the following notes.

[0119] According to one aspect of the present invention, a quartz oscillator is provided, comprising: a quartz resonating element, a base member on which the quartz resonating element is mounted, and a cover member of conductive material joined to the base member by a joining member with a conductive adhesive sandwiched between them, forming an internal space between the cover member and the base member in which the quartz resonating element is disposed. The cover member has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base member. The side wall portion has a facing surface opposite to the base member. In the base member, a power supply electrode for connecting the quartz resonating element and a grounding electrode for grounding are provided. The grounding electrode is electrically connected to the cover member via the joining member. The conductive adhesive has a resin-based adhesive and a conductive filler dispersed in the resin-based adhesive. The particle size R of the conductive filler satisfies the following relationship: 4μm≤R≤15μm.

[0120] Therefore, by utilizing a cover component that provides electromagnetic shielding through grounding, noise caused by the entry and exit of electromagnetic waves can be reduced. Furthermore, it allows contact between the conductive filler, the power supply electrode, and the cover component, and reduces the thickness of the connecting parts. Thus, the rate of defective products due to ungrounded cover components can be reduced, as can the rate of defective products with frequency variations caused by poor leakage.

[0121] As one method, a protective film of insulating material is provided in the base component, which covers at least the area of ​​the power supply electrode facing the opposite surface. The protective film is in contact with the joint component. The gap G1 between the grounding electrode and the opposite surface and the gap G2 between the protective film and the opposite surface satisfy the following relationship: 0 < G2 - G1 < 13 μm.

[0122] According to another aspect of the present invention, a quartz oscillator is provided, comprising: a quartz resonating element, a base member on which the quartz resonating element is mounted, and a cover member of conductive material joined to the base member by a bonding member with a conductive adhesive sandwiched between them, forming an internal space between the cover member and the base member in which the quartz resonating element is disposed. The cover member has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base member. The side wall portion has a facing surface opposite to the base member. In the base member, a power supply electrode for connecting the quartz resonating element and a grounding electrode for grounding are provided. The grounding electrode is electrically connected to the cover member via the bonding member. The conductive adhesive has a resin-based adhesive and a conductive filler dispersed in the resin-based adhesive. In the base member, a protective film of insulating material is provided, at least covering the area of ​​the power supply electrode facing the facing surface. The protective film is in contact with the bonding member. The gap G1 between the grounding electrode and the facing surface and the gap G2 between the protective film and the facing surface satisfy the following relationship: 0 ≤ G2 - G1 ≤ 13 μm.

[0123] Therefore, by utilizing a cover component that provides electromagnetic shielding through grounding, noise caused by the entry and exit of electromagnetic waves can be reduced. Furthermore, contact between the conductive filler, the power supply electrode, and the cover component can be achieved, reducing the thickness of the joint components. Consequently, the rate of defective products due to ungrounded cover components can be reduced, as can the rate of defective products with frequency variations caused by poor leakage.

[0124] In one approach, the gap G2 between the protective film and the opposing surface satisfies the following relationship: 2μm≤G2≤20μm.

[0125] This allows the conductive filler to contact both the power supply electrode and the cover component, and reduces the thickness of the joint components. Consequently, it reduces the rate of defective products where the cover component cannot be grounded, and also reduces the rate of defective products with fluctuating frequencies due to poor leakage.

[0126] In one approach, the gap G2 between the protective film and the opposing surface and the particle size R of the conductive filler satisfy the following relationship: R < G2.

[0127] This prevents conductive fillers from coming into contact with each other in unnecessary areas. Consequently, it reduces the rate of defective products caused by short circuits in the quartz vibrating element and cover components.

[0128] In one approach, the conductive filler has a spherical resin core and a metal film covering the resin core.

[0129] In one approach, the resin core is made of styrene-based or acrylic resin, and the metal film is made of nickel.

[0130] As one approach, resin-based adhesives are epoxy-based thermosetting resins.

[0131] In one approach, the conductive adhesive also has an insulating filler dispersed in the resin-based adhesive, wherein the particle size R of the conductive filler and the particle size r of the insulating filler satisfy the following relationship: r < R.

[0132] This allows for the suppression of deformation of the conductive filler by the insulating filler. Consequently, it reduces the rate of defective products where the cover component cannot be grounded.

[0133] The embodiments of the present invention are not limited to quartz oscillators, but can also be applied to piezoelectric oscillators. An example of a piezoelectric resonator unit is a quartz crystal resonator unit incorporating a quartz crystal resonator. The quartz crystal resonator utilizes a quartz crystal element as a piezoelectric plate excited by the piezoelectric effect. The piezoelectric plate can also be formed from any piezoelectric material such as a piezoelectric single crystal, piezoelectric ceramic, piezoelectric thin film, or piezoelectric polymer film. As an example, lithium niobate (LiNbO3) can be cited as a piezoelectric single crystal. Similarly, piezoelectric ceramics can include barium titanate (BaTiO3), lead titanate (PbTiO3), lead zirconate titanate (Pb(ZrxTi1-x)O3; PZT), aluminum nitride (AlN), lithium niobate (LiNbO3), lithium metaniobate (LiNb2O6), and bismuth titanate (Bi4Ti3O3). 12 Lithium tantalate (LiTaO3), lithium tetraborate (Li2B4O7), lanthanum gallium silicate (La3Ga5SiO) 14 Examples of piezoelectric thin films include piezoelectric ceramics formed on substrates such as quartz or sapphire by sputtering. Examples of piezoelectric polymer films include polylactic acid (PLA), polyvinylidene fluoride (PVDF), or vinylidene fluoride / trifluoroethylene (VDF / TrFE) copolymers. These various piezoelectric materials can be used in a stacked manner or stacked with other components.

[0134] The embodiments of the present invention are not particularly limited to devices that utilize the piezoelectric effect for electromechanical energy conversion, such as timing devices, sound generators, oscillators, and load sensors, and can be appropriately applied.

[0135] As described above, according to one aspect of the present invention, a piezoelectric vibrator capable of suppressing noise and the generation of defective products can be provided.

[0136] Furthermore, the embodiments described above are provided to facilitate understanding of the invention and are not intended to limit the scope of the invention. The invention can be modified / improved without departing from its spirit, and its equivalents are also included. That is, any modifications made by those skilled in the art to the various embodiments that possess the features of the invention are included within the scope of the invention. For example, the elements, their configurations, materials, conditions, shapes, dimensions, etc., of each embodiment are not limited to the illustrated structures and can be appropriately modified. Additionally, the elements of each embodiment can be combined as long as it is technically feasible, and the structure formed by combining these elements is included within the scope of the invention as long as it contains the features of the invention.

[0137] Explanation of reference numerals in the attached figures

[0138] 1…quartz oscillator, 10…quartz resonating element, 30…base component, 31…substrate, 33a, 33b…electrode pads, 33c…upper surface electrode, 34a~34d…side electrode, 35a~35d…external electrode, 39…protective film, 40…cover component, 41…top wall, 42…side wall, 43B…opposing surface, 50…joining component, 51…resin-based adhesive, 52…conductive filler, 53…insulating filler.

Claims

1. A piezoelectric oscillator, comprising: piezoelectric vibration element; The base component is equipped with the aforementioned piezoelectric vibration element; A cover component made of conductive material, forming an internal space between the cover component and the base component, wherein the piezoelectric vibration element is disposed in the internal space; and A joining component joins the base component and the cover component, and the joining component is provided with a conductive adhesive. The aforementioned cover component has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base component, the side wall portion having a facing surface opposite to the base component. The base component is provided with a power supply electrode for connecting the piezoelectric vibration element and a grounding electrode for grounding. The grounding electrode is electrically connected to the cover component via the connecting component. The aforementioned conductive adhesive comprises a resin-based adhesive and conductive fillers dispersed within the resin-based adhesive. The particle size R of the above conductive filler satisfies the following relationship: 4μm≤R≤15μm In the aforementioned base component, a protective film made of insulating material is provided, wherein, The aforementioned protective film at least covers the area of ​​the power supply electrode facing the aforementioned opposing surface, and the aforementioned protective film is in contact with the aforementioned bonding member. The gap G1 between the grounding electrode and the opposing surface and the gap G2 between the protective film and the opposing surface satisfy the following relationship: 0≤G2-G1≤13μm.

2. The piezoelectric oscillator according to claim 1, wherein, The gap G2 between the above-mentioned protective film and the above-mentioned opposing surface satisfies the following relationship: 2μm≤G2≤20μm.

3. The piezoelectric oscillator according to claim 1 or 2, wherein, The gap G2 between the above-mentioned protective film and the above-mentioned opposing surface and the particle size R of the above-mentioned conductive filler satisfy the following relationship: R < G2.

4. The piezoelectric oscillator according to claim 1 or 2, wherein, The conductive filler described above has a spherical resin core and a metal film covering the resin core.

5. The piezoelectric vibrator according to claim 4, wherein, The aforementioned resin core is a styrene-based resin or an acrylic-based resin. The aforementioned metal film is nickel.

6. The piezoelectric oscillator according to claim 1 or 2, wherein, The above-mentioned resin-based adhesives are epoxy-based thermosetting resins.

7. The piezoelectric oscillator according to claim 1 or 2, wherein, The aforementioned conductive adhesive also contains insulating fillers dispersed within the aforementioned resin-based adhesive. The particle size R of the conductive filler and the particle size r of the insulating filler satisfy the following relationship: r＜R。 8. The piezoelectric oscillator according to claim 1 or 2, wherein, A portion of the conductive filler is deformed by being clamped between the grounding electrode and the cover component.

9. The piezoelectric oscillator according to claim 1 or 2, wherein, The above-mentioned power supply electrodes have: The electrode pads are disposed on the upper surface of the cover member side of the base member and are surrounded by the joint member when viewed from above. Side electrodes are disposed on the side portion of the aforementioned base component; and Wiring electrodes are disposed on the upper surface to electrically connect the electrode pads and the side electrodes.

10. A piezoelectric oscillator, comprising: piezoelectric vibration element; The base component is equipped with the aforementioned piezoelectric vibration element; A cover component made of conductive material, forming an internal space between the cover component and the base component, wherein the piezoelectric vibration element is disposed in the internal space; and A joining component joins the base component and the cover component, and the joining component is provided with a conductive adhesive. The aforementioned cover component has a top wall portion and a side wall portion extending from the outer edge of the top wall portion toward the base component, the side wall portion having a facing surface opposite to the base component. The base component is provided with a power supply electrode for connecting the piezoelectric vibration element and a grounding electrode for grounding. The grounding electrode is electrically connected to the cover component via the connecting component. The aforementioned conductive adhesive comprises a resin-based adhesive and conductive fillers dispersed within the resin-based adhesive. In the aforementioned base component, a protective film made of insulating material is provided, wherein, The aforementioned protective film at least covers the area of ​​the power supply electrode facing the aforementioned opposing surface, and the aforementioned protective film is in contact with the aforementioned bonding member. The gap G1 between the grounding electrode and the opposing surface and the gap G2 between the protective film and the opposing surface satisfy the following relationship: 0≤G2-G1≤13μm.

11. The piezoelectric oscillator according to claim 10, wherein, The gap G2 between the above-mentioned protective film and the above-mentioned opposing surface satisfies the following relationship: 2μm≤G2≤20μm.

12. The piezoelectric oscillator according to claim 10 or 11, wherein, The gap G2 between the above-mentioned protective film and the above-mentioned opposing surface and the particle size R of the above-mentioned conductive filler satisfy the following relationship: R < G2.

13. The piezoelectric oscillator according to claim 10 or 11, wherein, The conductive filler described above has a spherical resin core and a metal film covering the resin core.

14. The piezoelectric oscillator according to claim 13, wherein, The aforementioned resin core is a styrene-based resin or an acrylic-based resin. The aforementioned metal film is nickel.

15. The piezoelectric oscillator according to claim 10 or 11, wherein, The above-mentioned resin-based adhesives are epoxy-based thermosetting resins.

16. The piezoelectric oscillator according to claim 10 or 11, wherein, The aforementioned conductive adhesive also contains insulating fillers dispersed within the aforementioned resin-based adhesive. The particle size R of the conductive filler and the particle size r of the insulating filler satisfy the following relationship: r＜R。 17. The piezoelectric oscillator according to claim 10 or 11, wherein, A portion of the conductive filler is deformed by being clamped between the grounding electrode and the cover component.

18. The piezoelectric oscillator according to claim 10 or 11, wherein, The above-mentioned power supply electrodes have: The electrode pads are disposed on the upper surface of the cover member side of the base member and are surrounded by the joint member when viewed from above. Side electrodes are disposed on the side portion of the aforementioned base component; and Wiring electrodes are disposed on the upper surface to electrically connect the electrode pads and the side electrodes.

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