Vibration elements, vibrators, and electronic devices

Abstract

A vibration element, a vibrator, and an electronic device. A vibration element is provided whose oscillation characteristics are less likely to deviate. The vibration element comprises a first excitation electrode, a first pad electrode, and a first lead-out wiring arranged on the first surface of a vibration piece; a second excitation electrode, a second pad electrode, and a second lead-out wiring arranged on the second surface of the vibration piece; and a spiral first electrode pattern arranged on the first surface of the vibration piece, wherein the first excitation electrode and the second excitation electrode are arranged opposite each other with the vibration piece interposed therebetween, the first center side end of the first electrode pattern is electrically connected to the second lead-out wiring via a through electrode provided on the vibration piece, the first peripheral side end of the first electrode pattern is electrically connected to the first lead-out wiring, the first lead-out wiring is electrically connected to at least one of the first excitation electrode and the first pad electrode, and the second lead-out wiring is electrically connected to at least one of the second excitation electrode and the second pad electrode.

Description

Technical Field

[0001] The present invention relates to a vibration element, a vibrator and an electronic device. Background Art

[0002] Vibration elements with excitation electrodes on both sides of a quartz resonator are widely used. For example, Patent Document 1 discloses a vibration element with a spiral electrode pattern in addition to the excitation electrode and pad electrode. The spiral electrode pattern is an inductor, with a pad electrode at its center. The outer edges of the inductor are electrically connected to the excitation electrodes via wiring.

[0003] In the vibrating element of this document, Figure 7 As shown, one end of a bonding wire is connected to a pad electrode located at the center of the inductor, and electrical connection is made in a state where the bonding wire and the inductor intersect in a plan view.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-23015

[0005] However, the vibration element of Patent Document 1 has a problem in that the oscillation characteristics of the vibration element may vary. Specifically, the magnetic flux generated in the inductor magnetically couples with the bonding wire disposed nearby, causing variations in the inductance value. Summary of the Invention

[0006] The vibration element comprises: a first excitation electrode, a first pad electrode and a first lead-out wiring arranged on one surface of a vibration piece; a second excitation electrode, a second pad electrode and a second lead-out wiring arranged on the other surface of the vibration piece; and a spiral first electrode pattern arranged on the one surface of the vibration piece, the first excitation electrode and the second excitation electrode are arranged opposite to each other with the vibration piece in between, the end portion on the center side of the first electrode pattern is electrically connected to the second lead-out wiring via a through electrode provided on the vibration piece, the end portion on the outer peripheral side of the first electrode pattern is electrically connected to the first lead-out wiring, the first lead-out wiring is electrically connected to at least one of the first excitation electrode and the first pad electrode, and the second lead-out wiring is electrically connected to at least one of the second excitation electrode and the second pad electrode.

[0007] A vibrator includes: the above-mentioned vibration element; and a package on which the vibration element is mounted.

[0008] An electronic device includes: the vibration element described above; a package on which the vibration element is mounted; and a drive circuit substrate that supplies a drive voltage to the first excitation electrode and the second excitation electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1It is a schematic plan view showing the structure of the vibration element according to the first embodiment.

[0010] Figure 2 is a schematic side sectional view showing the structure of a vibration element.

[0011] Figure 3 It is a schematic top view showing the structure of the vibration element.

[0012] Figure 4 This is a circuit diagram showing an example of an oscillator circuit.

[0013] Figure 5 A circuit diagram illustrating an example of an equivalent circuit of a piezoelectric vibrating portion.

[0014] Figure 6 It is a schematic plan view showing the structure of the vibration element according to the second embodiment.

[0015] Figure 7 is a schematic side sectional view showing the structure of a vibration element.

[0016] Figure 8 It is a schematic top view showing the structure of the vibration element.

[0017] Figure 9 It is a schematic plan view showing the structure of the vibration element according to the third embodiment.

[0018] Figure 10 is a schematic side sectional view showing the structure of a vibration element.

[0019] Figure 11 It is a schematic top view showing the structure of the vibration element.

[0020] Figure 12 It is a schematic plan view showing the structure of the vibration element according to the fourth embodiment.

[0021] Figure 13 It is a schematic top view showing the structure of the vibration element.

[0022] Figure 14 It is a schematic plan view showing the structure of the vibration element according to the fifth embodiment.

[0023] Figure 15 It is a schematic plan view showing the structure of the vibration element according to the sixth embodiment.

[0024] Figure 16 is a schematic side sectional view showing the structure of a vibration element.

[0025] Figure 17 It is a schematic side sectional view showing the structure of a vibrator according to the seventh embodiment.

[0026] Figure 18 It is a schematic side sectional view showing the structure of the electronic device according to the eighth embodiment.

[0027] Description of labels

[0028] 1, 40, 43, 51, 55, 61, 65 vibration element; 2 vibration piece; 2a as the first surface of one surface; 2b as the second surface of the other surface; 3 first excitation electrode; 4 first pad electrode; 5, 46, 52 first lead-out wiring; 6 first electrode pattern; 6a as the first peripheral end portion of the peripheral end portion; 6b as the first center end portion of the center end portion; 8 second excitation electrode; 9 second pad electrode; 11, 49, 53 2 lead-out wiring; 15 through-electrode; 16 piezoelectric vibrating portion serving as a vibrating portion; 17 first region; 18 second region; 21, 81 electronic device; 41a second peripheral end portion serving as a peripheral end portion; 41b second central end portion serving as a central end portion; 41 second electrode pattern; 46a first wiring serving as the first lead-out wiring; 53b fourth wiring serving as the second lead-out wiring; 64 vibrator; 66, 83 package; 84 driving circuit substrate. DETAILED DESCRIPTION

[0029] First embodiment

[0030] In this embodiment, characteristic examples of the vibration element will be described with reference to the drawings. Figure 2 Shown along Figure 1 The cross section of line AA. Figure 3 Observed from the opposite side Figure 1 Diagram of a vibrating element.

[0031] like Figures 1 to 3 As shown, the vibration element 1 has a vibration plate 2. The material of the vibration plate 2 is a component having a piezoelectric effect. In the present embodiment, the material of the vibration plate 2 is quartz. The vibration plate 2 is formed using a quartz wafer as a single crystal substrate, which is cut at a predetermined cutting angle from a quartz Lambertian wafer formed by forming a block of a portion of an artificial quartz raw stone with a clear crystal axis. The predetermined cutting angle is a cutting angle that is tilted at a target angle relative to the crystal axis of the quartz. The vibrator 1 exhibits a thickness shear vibration mode formed using so-called AT-cut quartz cut at a cutting angle of 35°15′ from the crystal axis.

[0032] When viewed from above, the diaphragm 2 is a pentagon with one corner of the rectangle cut off. When viewed from above, the diaphragm 2 is long in one direction. The long directions are the longitudinal direction 56 and the X direction. The short directions of the diaphragm 2 are the width direction 57 and the Y direction. The thickness direction of the diaphragm 2 is the Z direction. The portion of the diaphragm 2 where one corner of the rectangle is cut off is in the positive X direction and the negative Y direction.

[0033] The diaphragm 2 has a first surface 2a as one surface and a second surface 2b as the other surface. The direction from the second surface 2b toward the first surface 2a is defined as the positive Z direction.

[0034] A first excitation electrode 3, a first pad electrode 4, and a first lead wire 5 are arranged on the first surface 2a of the vibrating element 2. The first lead wire 5 is electrically connected to both the first excitation electrode 3 and the first pad electrode 4. Furthermore, a spiral first electrode pattern 6 is arranged on the first surface 2a of the vibrating element 2. A first outer peripheral end 6a, which is an outer peripheral end of the first electrode pattern 6, is electrically connected to the first lead wire 5.

[0035] The first pad electrode 4 is located at a corner between the negative X and negative Y directions. The first excitation electrode 3 is located at a corner between the positive X and positive Y directions. Furthermore, a third pad electrode 7 is disposed on the first surface 2a. The third pad electrode 7 is located at a corner between the negative X and positive Y directions.

[0036] Second excitation electrode 8, second pad electrode 9, and second lead wire 11 are arranged on second surface 2b of vibrator element 2. First excitation electrode 3 and second excitation electrode 8 are arranged facing each other with vibrator element 2 interposed therebetween. Second lead wire 11 is electrically connected to both second excitation electrode 8 and second pad electrode 9.

[0037] The second pad electrode 9 and the third pad electrode 7 are arranged opposite each other with the vibrating element 2 interposed therebetween. The second pad electrode 9 and the third pad electrode 7 are electrically connected via a second side wiring 12. Furthermore, a fourth pad electrode 13 is arranged on the second surface 2b. The fourth pad electrode 13 and the first pad electrode 4 are arranged opposite each other with the vibrating element 2 interposed therebetween. The fourth pad electrode 13 and the first pad electrode 4 are electrically connected via a first side wiring 14. The second side wiring 12 and the first side wiring 14 are provided on the side surfaces of the vibrating element 2.

[0038] The first center-side end portion 6b, which is the center-side end portion of the first electrode pattern 6, is a square pad. On the second surface 2b, the second lead wiring 11 includes a connection pad 11a at a location opposite the first center-side end portion 6b across the vibrating element 2. A through-electrode 15 is provided on the vibrating element 2 between the connection pad 11a and the first center-side end portion 6b. The first center-side end portion 6b is electrically connected to the second lead wiring 11 via the through-electrode 15 provided on the vibrating element 2.

[0039] According to this structure, the vibrating element 2 has a spiral first electrode pattern 6 on the first surface 2a. The first electrode pattern 6 functions as an inductor. The first center-side end 6b of the first electrode pattern 6 is electrically connected to the second lead wiring 11 via the through electrode 15. The second lead wiring 11 is electrically connected to both the second excitation electrode 8 and the second pad electrode 9. Therefore, the first electrode pattern 6 is electrically connected to both the second excitation electrode 8 and the second pad electrode 9. The first peripheral-side end 6a of the first electrode pattern 6 is located on the first surface 2a and is electrically connected to the first lead wiring 5. The first lead wiring 5 is electrically connected to both the first excitation electrode 3 and the first pad electrode 4. Therefore, the first electrode pattern 6 is electrically connected to both the first excitation electrode 3 and the first pad electrode 4 located on the first surface 2a.

[0040] In the resonator element 1, unlike conventional techniques, there is no pad electrode at the first center-side end 6b of the first electrode pattern 6, and no wire bonding is performed at the first center-side end 6b of the first electrode pattern 6. Consequently, variations in the inductance value of the first electrode pattern 6 can be suppressed. The distance between the second lead wire 11 and the first electrode pattern 6 can be set to at least the thickness of the resonator element 2. Consequently, magnetic coupling between the magnetic flux generated in the first electrode pattern 6 and the second lead wire 11 can be reduced. As a result, variations in oscillation characteristics are less likely to occur, resulting in an excellent resonator element 1.

[0041] The through-electrode 15 is arranged on the center side of the first electrode pattern 6. The second lead-out wiring 11 intersects the first electrode pattern 6 when viewed in plan from the Z direction, and is arranged from the through-electrode 15 to the outside of the first electrode pattern 6.

[0042] This configuration allows the second lead wire 11 and the first electrode pattern 6 to be spaced at least by the thickness of the vibrating element 2 . This reduces magnetic coupling between the magnetic flux generated by the first electrode pattern 6 and the second lead wire 11 .

[0043] In the vibration element 1, the first pad electrode 4, the first electrode pattern 6, and the first excitation electrode 3 are arranged in this order along the longitudinal direction 56 of the vibration piece 2. The portion of the vibration element 1 where the first excitation electrode 3 and the second excitation electrode 8 are provided serves as a piezoelectric vibrating portion 16, which is the vibrating portion that vibrates the vibration piece 2. The first pad electrode 4 and the third pad electrode 7 are fixed to the vibration element 1, and the piezoelectric vibrating portion 16 vibrates.

[0044] This configuration can increase the distance between the first pad electrode 4 and the first excitation electrode 3 compared to when there is no first electrode pattern 6. Therefore, when stress is applied to the vibrating element 2 on the first pad electrode 4 side, the stress can be prevented from affecting the piezoelectric vibrating portion 16.

[0045] The thickness of the vibrating element 2 in the first region 17, where the first excitation electrode 3 and the second excitation electrode 8 are provided, is thinner than the thickness of the vibrating element 2 in the second region 18, where the first pad electrode 4 and the second pad electrode 9 are provided. In other words, the vibrating element 1 has a so-called inverted mesa structure. A recess 2 c is formed in the vibrating element 2 in the first region 17.

[0046] With this structure, the thickness of the vibrating element 2 is relatively thin in the first region 17 where the first excitation electrode 3 and the second excitation electrode 8 are provided. This increases the vibration frequency of the piezoelectric vibrating portion 16. Consequently, a vibrating element 1 capable of handling high frequencies can be realized. Furthermore, when high frequency handling is not required, the thickness of the second region 18 can be the same as or thicker than that of the first region 17.

[0047] The width of the vibrating plate 2 in the positive X direction is narrower than the width in the negative X direction. Therefore, the mass of the vibrating plate 2 in the positive X direction is smaller than the mass in the negative X direction. The negative X direction side of the vibrating element 1 is fixed, acting as a cantilever beam. When an impact is applied to the vibrating element 1, the positive X direction side of the vibrating element 1 vibrates. Since the mass of the vibrating element 1 in the positive X direction is smaller than the mass of the negative X direction side, vibration can be suppressed.

[0048] The resonator element 1 can be manufactured using a known method. A quartz crystal wafer is etched to form through-holes for the through-electrode 15, the first region 17, and the outer shape of the resonator element 2. Next, a metal film made of, for example, gold is formed on a nickel or chromium base layer by vapor deposition or sputtering. The metal film is then patterned using photolithography and etched to form the first excitation electrode 3, the second excitation electrode 8, the first pad electrode 4, the second pad electrode 9, the third pad electrode 7, the fourth pad electrode 13, the first electrode pattern 6, the first lead wiring 5, the second lead wiring 11, the through-electrode 15, and the like.

[0049] like Figure 4 As shown, the electronic device 21 includes a vibration element 1 and a drive circuit substrate 22. Figure 4 A portion of the circuit is shown, and the circuit for oscillation is omitted. The driving circuit board 22 includes a first terminal 23 and a second terminal 24. The vibration element 1 is connected between the first terminal 23 and the second terminal 24. Figure 4 and Figure 5 The connections in the description indicate electrical connections.

[0050] The drive circuit board 22 includes a control voltage input terminal 25. The control voltage input terminal 25 is connected to one end of a control voltage applying resistor 26. The other end of the control voltage applying resistor 26 is connected to a varactor diode 27 and the first terminal 23. The cathode of the varactor diode 27 is connected to the control voltage applying resistor 26, and the anode is connected to a ground 28.

[0051] Second terminal 24 is connected to the input of amplifier 29. The output of amplifier 29 is connected to frequency output terminal 31. A first capacitor 32 and a second capacitor 33 are connected in series between second terminal 24 and ground 28. One end of first capacitor 32 is connected to second terminal 24. The other end of first capacitor 32 is connected to one end of second capacitor 33 and frequency output terminal 31. The other end of second capacitor 33 is connected to ground 28.

[0052] In the vibration element 1 , the first electrode pattern 6 is electrically connected in parallel to the piezoelectric vibration portion 16 in which the first excitation electrode 3 and the second excitation electrode 8 sandwich the vibration element 2 .

[0053] With this structure, the first electrode pattern 6 is connected in parallel with the piezoelectric vibrating portion 16. Therefore, the first electrode pattern 6 functions as an inductor, eliminating parasitic capacitance. Parasitic capacitance includes capacitance generated by the package's wiring. Since the first electrode pattern 6 is formed without surrounding the first excitation electrode 3, eddy currents generated in the first excitation electrode 3 can be reduced. Consequently, the first electrode pattern 6 can achieve an inductor with a high Q value.

[0054] like Figure 5 As shown, a general equivalent circuit of the piezoelectric vibrating portion 16 is represented by a circuit in which an equivalent series inductor 34, an equivalent series capacitor 35, and an equivalent series resistor 36 are connected in series, and an equivalent parallel capacitor 37 is connected in parallel with the equivalent series inductor 34, the equivalent series capacitor 35, and the equivalent series resistor 36. The first electrode pattern 6 can cancel the parasitic capacitance including the equivalent parallel capacitor 37. Furthermore, when the equivalent parallel capacitor 37 is C0 and the equivalent series capacitor 35 is C1, it is preferable that C0 / C1 be small. This can expand the frequency range.

[0055] When the vibration frequency of the piezoelectric vibrating portion 16 is ω and the inductance of the first electrode pattern 6 is L, it is preferable to set L within the range of ωC0 > 1 / (ωL). This can eliminate the influence of C0. Furthermore, to obtain a large L value, the vibrating element 1 can be stacked with another vibrating element forming an inductor.

[0056] The thickness of the first electrode pattern 6 is preferably thicker than the thicknesses of the first excitation electrode 3 and the second excitation electrode 8. Furthermore, it is preferable to optimize the Q value of the first electrode pattern 6 and the CI value of the piezoelectric vibrating portion 16.

[0057] Second embodiment

[0058] Figure 6 This is a diagram of the vibration element 40 as viewed from the first surface 2 a side. Figure 7 It is from along Figure 6 FIG is a diagram showing the vibration element 40 as viewed from the cross-sectional side along line BB. Figure 8 This is a diagram of the vibration element 40 viewed from the second surface 2b side. Figures 6 to 8 As shown, the vibration element 40 may include a second electrode pattern 41 on the second surface 2 b.

[0059] On the second surface 2b of the vibration element 40, the second excitation electrode 8 and the second pad electrode 9 are electrically connected via a second lead-out wiring 42. A spiral second electrode pattern 41 is provided on the second surface 2b. A second central end portion 41b, which is the central end portion of the second electrode pattern 41, is electrically connected to the first electrode pattern 6 via the through electrode 15. A second peripheral end portion 41a, which is the peripheral end portion of the second electrode pattern 41, is electrically connected to the second lead-out wiring 42.

[0060] With this structure, the first electrode pattern 6 is electrically connected to the second electrode pattern 41. Since both the first electrode pattern 6 and the second electrode pattern 41 are spiral-shaped, an inductor having a larger number of turns can be formed compared to a case where only the first electrode pattern 6 is used.

[0061] Third embodiment

[0062] Figure 9 This is a diagram of the vibration element 43 as viewed from the first surface 2 a side. Figure 10 It is from along Figure 9 A cross-sectional view of the CC line. Figure 11 This is a diagram of the vibration element 43 viewed from the second surface 2b side. Figures 9 to 11 As shown, in the vibration element 43 , the first electrode pattern 6 is electrically connected in series to the piezoelectric vibration portion 16 , wherein the first excitation electrode 3 and the second excitation electrode 8 sandwich the vibration element 2 in the piezoelectric vibration portion 16 .

[0063] The first surface 2a includes a first pad electrode 44 at a corner in the negative X direction and the positive Y direction. The second surface 2b includes a fourth pad electrode 45 at a location opposite the first pad electrode 44 across the vibrating element 2. The first pad electrode 44 and the fourth pad electrode 45 are electrically connected via the second side surface wiring 12. The first surface 2a includes a first lead wiring 46. The first lead wiring 46 includes a first wiring 46a and a second wiring 46b. The first excitation electrode 3 and the first pad electrode 44 are electrically connected via the first wiring 46a, which serves as the first lead wiring.

[0064] The first surface 2a includes a third pad electrode 47 at a corner in the negative X and negative Y directions. The second surface 2b includes a second pad electrode 48 at a location opposing the third pad electrode 47 across the vibrating element 2. The third pad electrode 47 and the second pad electrode 48 are electrically connected via the first side wiring 14. The first outer peripheral end portion 6a and the third pad electrode 47 are electrically connected via the second wiring 46b.

[0065] The second surface 2b includes a second lead-out wiring 49. The second lead-out wiring 49 is electrically connected to the through-electrode 15. Furthermore, the second lead-out wiring 49 is electrically connected to the second excitation electrode 8.

[0066] According to this structure, the first electrode pattern 6 is connected in series with the piezoelectric vibrating portion 16. Therefore, the first electrode pattern 6 functions as an inductor, and when the vibrating element 43 is used in a voltage-controlled quartz oscillator, the frequency variable range can be expanded.

[0067] Fourth embodiment

[0068] Figure 12 This is a diagram of the vibration element 51 as viewed from the first surface 2 a side. Figure 13 This is a diagram of the vibration element 51 viewed from the second surface 2b side. Figure 12 and Figure 13 As shown, in the vibration element 51 , the first electrode pattern 6 is electrically connected in series to the piezoelectric vibration portion 16 , wherein the first excitation electrode 3 and the second excitation electrode 8 sandwich the vibration element 2 in the piezoelectric vibration portion 16 .

[0069] The first surface 2a includes a first lead-out wiring 52. The first outer peripheral end 6a of the first electrode pattern 6 is electrically connected to the first lead-out wiring 52. The first lead-out wiring 52 is electrically connected to the first excitation electrode 3.

[0070] The first surface 2a has a first pad electrode 44 at a corner in the negative X direction and the positive Y direction. The second surface 2b has a fourth pad electrode 45 at a location facing the first pad electrode 44 across the vibrating element 2. The first pad electrode 44 and the fourth pad electrode 45 are electrically connected via the second side surface wiring 12.

[0071] The second surface 2b includes a second lead wire 53. The second lead wire 53 includes a third wire 53a and a fourth wire 53b. The third wire 53a electrically connects the second excitation electrode 8 and the fourth pad electrode 45. The third wire 53a is electrically connected to the first pad electrode 44 via the fourth pad electrode 45 and the second side surface wire 12.

[0072] The first surface 2a has a third pad electrode 47 at a corner in the negative X and Y directions. The second surface 2b has a second pad electrode 48 at a location facing the third pad electrode 47 across the vibrating element 2. The third pad electrode 47 and the second pad electrode 48 are electrically connected via the first side surface wiring 14.

[0073] The fourth wiring 53b, which serves as the second lead wiring, is electrically connected to the through-electrode 15 and the second pad electrode 48. The third pad electrode 47, the first side wiring 14, the second pad electrode 48, the fourth wiring 53b, the through-electrode 15, the first electrode pattern 6, the first lead wiring 52, and the first excitation electrode 3 are connected in series in this order.

[0074] According to this structure, the first electrode pattern 6 is connected in series with the piezoelectric vibrating portion 16. Therefore, the first electrode pattern 6 functions as an inductor, and when used in a voltage-controlled quartz crystal oscillator, the frequency variable range can be expanded.

[0075] Fifth embodiment

[0076] Figure 14 This is a diagram of the vibration element 55 as viewed from the first surface 2a side. Figure 14 As shown, the vibration element 55 includes the vibration piece 2. The positive X direction and the negative X direction are longitudinal directions 56. The positive Y direction and the negative Y direction are width directions 57. The width direction 57 of the vibration piece 2 is shorter than the length in the longitudinal direction 56.

[0077] A center line passing through the center of the vibrating element 2 in the width direction 57 and along the length direction 56 is defined as a first center line 58. With respect to the first center line 58, the first excitation electrode 3 is positioned on the positive Y direction side, and the center 6c of the first electrode pattern 6 is positioned on the negative Y direction side. Therefore, with respect to the first center line 58, the first excitation electrode 3 is positioned on one side, and the center 6c of the first electrode pattern 6 is positioned on the other side. One side is the positive Y direction side, and the other side is the negative Y direction side.

[0078] With this configuration, the distance between the first excitation electrode 3 and the first electrode pattern 6 can be increased compared to a case where the first excitation electrode 3 and the center 6 c of the first electrode pattern 6 are located on one side relative to the first center line 58 along the longitudinal direction 56. As a result, the magnetic flux generated in the first electrode pattern 6 can be reduced from magnetically coupling with the first excitation electrode 3, thereby reducing the effect of the first excitation electrode 3 on the inductance value of the first electrode pattern 6.

[0079] A center line passing through the center of the vibrating element 2 in the longitudinal direction 56 and along the width direction 57 is defined as a second center line 59. With respect to the second center line 59, the first excitation electrode 3 is positioned on the positive X-direction side, and the center 6c of the first electrode pattern 6 is positioned on the negative X-direction side. Therefore, with respect to the second center line 59, the first excitation electrode 3 is positioned on one side, and the center 6c of the first electrode pattern 6 is positioned on the other side. One side is the positive X-direction side, and the other side is the negative X-direction side.

[0080] With this configuration, the distance between the first excitation electrode 3 and the first electrode pattern 6 can be increased compared to a case where the first excitation electrode 3 and the center 6 c of the first electrode pattern 6 are located on one side relative to the second center line 59 along the width direction 57. As a result, the magnetic flux generated in the first electrode pattern 6 can be reduced from magnetically coupling with the first excitation electrode 3, thereby reducing the effect of the first excitation electrode 3 on the inductance value of the first electrode pattern 6.

[0081] In the vibrating element 55, the first excitation electrode 3 is arranged on one side relative to the first center line 58 and the second center line 59, and the center 6c of the first electrode pattern 6 is arranged on the other side. This reduces the effect of the first excitation electrode 3 on the inductance of the first electrode pattern 6. One side is the positive X-direction side and the positive Y-direction side. The other side is the negative X-direction side and the negative Y-direction side.

[0082] Sixth embodiment

[0083] Figure 15 This is a diagram of the vibration element 61 as viewed from the first surface 2 a side. Figure 16 It is from along Figure 15 The figure of the vibration element 61 is observed from the cross-sectional side of the DD line. Figure 15 and Figure 16 As shown, the vibration element 61 has a first electrode pattern 6 on the first surface 2a. The vibration element 61 has a metal hole 62 inside the first electrode pattern 6. The metal hole 62 is insulated from the first electrode pattern 6 and electrically floats. The metal hole 62 is made of a material with high magnetic permeability. In this embodiment, for example, the material of the metal hole 62 is pure iron.

[0084] According to this configuration, by providing the metal hole 62 having low magnetic resistance inside the magnetic flux of the inductor, it is possible to increase the inductance value of the first electrode pattern 6. The number of the metal hole 62 is not limited to one, and a plurality of metal holes may be provided.

[0085] Seventh embodiment

[0086] like Figure 17As shown, the vibrator 64 includes a vibration element 65 and a package 66 on which the vibration element 65 is mounted. As the vibration element 65, any one of the vibration element 1, the vibration element 40, the vibration element 43, the vibration element 51, the vibration element 55, and the vibration element 61 is used.

[0087] Specifically, the package 66 includes a package body 67 and a cover member 68 . The package body 67 is formed into a rectangular box shape to accommodate the vibration element 65 , and the cover member 68 is made of metal, ceramics, glass, or the like.

[0088] The package body 67 is formed by stacking a first substrate 69, a second substrate 71 and a sealing ring 72. A plurality of mounting terminals 73 are formed on the outer bottom surface of the first substrate 69. The second substrate 71 is an annular body with the central portion removed. A sealing ring 72 made of kovar alloy or the like is formed on the upper periphery of the second substrate 71. A cavity 74 for accommodating the vibration element 65 is formed by the second substrate 71. At a predetermined position on the upper surface of the first substrate 69, a plurality of element mounting pads 75 are provided that are electrically connected to the mounting terminals 73 through wiring (not shown) formed inside the first substrate 69. The element mounting pads 75 are arranged so as to correspond to the first pad electrode 4, the third pad electrode 7 or the first pad electrode 44, the third pad electrode 47 when the vibration element 65 is mounted.

[0089] The first substrate 69 and the second substrate 71 of the package body 67 are made of a ceramic insulating material or the like. The electrodes and terminals provided on the package body 67, as well as the wiring patterns or intra-layer wiring patterns that electrically connect them, are typically formed by screen-printing a metal wiring material such as tungsten or molybdenum onto the ceramic insulating material, firing the printed material, and then plating the printed material with nickel, gold, or the like.

[0090] When supporting and fixing the vibration element 65, a conductive adhesive 76 is first applied to the first pad electrode 4, the third pad electrode 7, or the first pad electrode 44, the third pad electrode 47, and the element mounting pad 75 of the vibration element 65. The first pad electrode 4, the third pad electrode 7, or the first pad electrode 44, the third pad electrode 47 is then placed thereon, and a load is applied. The conductive adhesive 76 can be, for example, a polyimide, silicone, or epoxy resin mixed with silver wire, nickel powder, or the like.

[0091] Next, to cure the conductive adhesive 76, the conductive adhesive 76 is heated in a high-temperature furnace at a predetermined temperature for a predetermined time. After curing, the conductive adhesive 76 is annealed. Next, frequency adjustment is performed by adding or removing mass from the second excitation electrode 8. When reducing the mass of the second excitation electrode 8, to prevent metal powder generated from adhering to the first electrode pattern 6, the first electrode pattern 6 is preferably positioned opposite the first substrate 69.

[0092] Next, a sealing ring 72 is formed on the upper surface of the second substrate 71. The cover member 68 is placed on the sealing ring 72. The cover member 68 is seam-welded in a vacuum or nitrogen atmosphere. The cavity 74 is sealed, and the vibrator 64 is completed.

[0093] With this structure, vibrator 64 includes any one of the aforementioned vibrating elements 1, 40, 43, 51, 55, and 61 within package 66. Each of the aforementioned vibrating elements 1, 40, 43, 51, 55, and 61 has excellent oscillation characteristics. Therefore, vibrator 64 can be a vibrator having a vibrating element with excellent oscillation characteristics.

[0094] 8th embodiment

[0095] like Figure 18 As shown, an electronic device 81 includes a vibration element 65, a package 83 on which the vibration element 65 is mounted, and a drive circuit board 84 for supplying a drive voltage to the first excitation electrode 3 and the second excitation electrode 8. The vibration element 65 can be any one of the vibration element 1, the vibration element 40, the vibration element 43, the vibration element 51, the vibration element 55, and the vibration element 61.

[0096] Specifically, the package 83 includes a package body 82 and a cover member 68. A drive circuit substrate 84 having an oscillation circuit mounted thereon excites the vibration element 65. The drive circuit substrate 84 is in the form of an IC chip.

[0097] The electronic device 81 is sealed by bonding the vibration element 65 and a drive circuit board 84 including an oscillation circuit to a cavity 74 inside the package body 82. The electronic device 81 is a surface mountable single-chip quartz oscillator called an SMD (Surface Mount Device).

[0098] The package body 82 is formed by stacking the first substrate 69, the second substrate 71, the third substrate 85, and the sealing ring 72. A plurality of mounting terminals 73 are formed on the outer bottom surface of the first substrate 69. The second substrate 71 and the third substrate 85 are ring-shaped bodies with the center portion removed. The sealing ring 72, made of a material such as Kovar, is formed on the upper periphery of the second substrate 71.

[0099] The second substrate 71 and the third substrate 85 form a cavity 74 for housing the vibration element 65. A recess 86 is formed on the third substrate 85, which houses the drive circuit substrate 84 carrying the oscillation circuit that excites the vibration element 65. A plurality of IC connection terminals 87 for connecting to the drive circuit substrate 84 are provided on the upper surface of the first substrate 69, which forms the bottom surface of the recess 86. A plurality of component mounting pads 75 are provided at predetermined positions on the upper surface of the third substrate 85, which are electrically connected to the mounting terminals 73 via wiring (not shown) formed inside the first substrate 69 and the third substrate 85. The component mounting pads 75 are arranged so as to correspond to the first pad electrode 4, the third pad electrode 7, or the first pad electrode 44, the third pad electrode 47 when the vibration element 65 is mounted.

[0100] The first to third substrates 69 to 85 of the package body 82 are made of a ceramic insulating material or the like. Furthermore, the electrodes and terminals provided on the package body 82, as well as the wiring patterns or intra-layer wiring patterns that electrically connect them, are typically formed by screen-printing a metal wiring material such as tungsten or molybdenum onto the ceramic insulating material, firing the printed material, and then plating the printed material with a layer of nickel, gold, or the like.

[0101] The driver circuit board 84 is bonded to the IC bonding terminals 87 provided on the bottom surface of the recessed portion 86 of the package body 82 using solder or an adhesive. In this embodiment, the driver circuit board 84 is bonded face-down to the IC bonding terminals 87 using bumps 88 made of metal or solder, etc., which are pre-formed on electrode pads (not shown) of the driver circuit board 84.

[0102] The vibration element 65 is bonded with the conductive adhesive 76 in a state where the first pad electrode 4 and the third pad electrode 7 or the first pad electrode 44 and the third pad electrode 47 are aligned with the element mounting pad 75 .

[0103] The cover member 68 is bonded to the second substrate 71 of the package body 82. Materials for the cover member 68 include, for example, 42 alloy (iron containing 42% nickel) or Kovar (an alloy of iron, nickel, and cobalt). The cover member 68 is seam welded to the second substrate 71 via a sealing ring 72 formed in a frame-shaped mold. The sealing ring 72 is made of, for example, an iron-nickel alloy.

[0104] The cavity 74 formed by the package body 82 and the cover member 68 serves as a space for the operation of the vibration element 65. The cavity 74 is sealed in a reduced-pressure space or an inert gas atmosphere.

[0105] With this structure, electronic device 81 includes any one of vibration element 1, vibration element 40, vibration element 43, vibration element 51, vibration element 55, and vibration element 61 within package 83. Each of the vibration elements 1, 40, 43, 51, 55, and 61 exhibits excellent oscillation characteristics. Therefore, electronic device 81 can include vibration element 65 exhibiting excellent oscillation characteristics.

Claims

1. A vibration element, characterized in that The vibration element has: a first excitation electrode, a first pad electrode, and a first lead wiring arranged on one surface of the vibrating element; a second excitation electrode, a second pad electrode, and a second lead wiring arranged on the other surface of the vibrating element; as well as a spiral first electrode pattern disposed on the one surface of the vibrating piece, The first excitation electrode and the second excitation electrode are arranged to face each other with the vibrating piece interposed therebetween. The end portion on the center side of the first electrode pattern is electrically connected to the second lead wiring via a through electrode provided on the vibrating element. The outer peripheral end of the first electrode pattern is electrically connected to the first lead wiring. The first lead wiring is electrically connected to at least one of the first excitation electrode and the first pad electrode. The second lead wiring is electrically connected to at least one of the second excitation electrode and the second pad electrode.

2. The vibration element according to claim 1, characterized in that The through electrode is arranged on the center side of the first electrode pattern, The second lead wiring intersects the first electrode pattern in a plan view and is arranged from the through electrode to the outside of the first electrode pattern.

3. The vibration element according to claim 1, wherein A spiral second electrode pattern is provided on the other surface. The end portion of the second electrode pattern on the center side is electrically connected to the first electrode pattern via the through electrode. An outer peripheral end portion of the second electrode pattern is electrically connected to the second lead wiring.

4. The vibration element according to any one of claims 1 to 3, characterized in that The first electrode pattern is electrically connected in parallel to a vibration portion in which the first excitation electrode and the second excitation electrode sandwich the vibration element.

5. The vibration element according to any one of claims 1 to 3, characterized in that The first electrode pattern is electrically connected in series to a vibration portion in which the first excitation electrode and the second excitation electrode sandwich the vibration element.

6. The vibration element according to any one of claims 1 to 3, characterized in that In the longitudinal direction of the vibrating element, the first pad electrode, the first electrode pattern, and the first excitation electrode are arranged in this order.

7. The vibration element according to claim 6, characterized in that The first excitation electrode is arranged on one side of a center line passing through the center in the width direction of the vibrating element and along the longitudinal direction, and the center of the first electrode pattern is arranged on the other side.

8. The vibration element according to claim 6, characterized in that The first excitation electrode is arranged on one side of a center line passing through the center in the longitudinal direction of the vibrating element and along the width direction, and the center of the first electrode pattern is arranged on the other side.

9. The vibration element according to any one of claims 1 to 3, characterized in that The thickness of the vibrating element in the first region where the first excitation electrode and the second excitation electrode are provided is thinner than the thickness of the vibrating element in the second region where the first pad electrode and the second pad electrode are provided.

10. A vibrator, characterized in that: The vibrator has: The vibration element according to any one of claims 1 to 9; and A package is provided in which the vibration element is mounted.

11. An electronic device, characterized in that: The vibration element according to any one of claims 1 to 9; a package equipped with the vibration element; A driving circuit substrate supplies a driving voltage to the first excitation electrode and the second excitation electrode.

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