Vibration elements and oscillators

Abstract

To provide a vibration element and an oscillator capable of suppressing a reduction in Q value of an inductance.SOLUTION: A vibration element has a vibration piece and an electrode pattern. The vibration piece has a first surface and a second surface in a head-and-tail relationship, and includes a first electrode-free area. The electrode pattern is arranged on the vibration piece while avoiding the first electrode-free area. The electrode pattern includes: a first excitation electrode arranged on the first surface; a second excitation electrode arranged on the second surface while opposing the first excitation electrode; and a spiral-shaped first electrode pattern arranged on the first surface and surrounding the first electrode-free area. The first electrode-free area intersects a central axis of a magnetic flux generated on the first electrode pattern.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration element and an oscillator. [Background technology]

[0002] Conventionally, quartz crystal resonator elements in which excitation electrodes are arranged on both sides of a quartz crystal resonator element have been widely known. For example, Patent Document 1 discloses a quartz crystal resonator element in which an inductor formed by a spiral electrode pattern is arranged in addition to excitation electrodes and pad electrodes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-23015 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the quartz crystal vibration element of Patent Document 1, the pad electrode is located at the center of the inductor, which causes a large amount of magnetic flux generated by the inductor to pass through the pad electrode, resulting in eddy current loss and a decrease in the Q value of the inductance. [Means for solving the problem]

[0005] The vibration element of the present invention includes a vibration element having a first surface and a second surface that are opposite surfaces and a first no-electrode region; an electrode pattern disposed on the vibrating element to avoid the first no-electrode region, The electrode pattern is a first excitation electrode disposed on the first surface; a second excitation electrode disposed on the second surface so as to face the first excitation electrode; a spiral first electrode pattern disposed on the first surface and surrounding the first no-electrode area; The first no-electrode region intersects with the central axis of the magnetic flux generated in the first electrode pattern.

[0006] The oscillator of the present invention comprises the above-described vibration element and a circuit element that causes the vibration element to oscillate; and a package that houses the vibration element and the circuit element. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a top view of the vibration element according to the first embodiment. [Figure 2] FIG. 2 is a bottom view of the vibration element shown in FIG. [Figure 3] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 4] 10A and 10B are schematic cross-sectional views for explaining the effect of the vibration element. [Figure 5] FIG. 10 is a top view of a vibration element according to a second embodiment. [Figure 6] FIG. 6 is a bottom view of the vibration element shown in FIG. [Figure 7] FIG. 10 is a cross-sectional view showing an oscillator according to a third embodiment. [Figure 8] FIG. 8 is a top view of the oscillator shown in FIG. [Figure 9] FIG. 2 is a circuit diagram showing an example of a circuit included in a circuit element. [Figure 10] FIG. 4 is a circuit diagram illustrating an example of an equivalent circuit of a vibration unit. DETAILED DESCRIPTION OF THE INVENTION

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the vibration element and oscillator of the present invention will be described in detail below with reference to the accompanying drawings.

[0009] First Embodiment Fig. 1 is a top view of the vibration element according to the first embodiment. Fig. 2 is a bottom view of the vibration element shown in Fig. 1. Fig. 3 is a cross-sectional view taken along line AA in Fig. 1. Fig. 4 is a schematic cross-sectional view for explaining the effect of the vibration element.

[0010] As shown in FIGS. 1 and 2, the vibration element 1 has a vibration element 2 and an electrode pattern 3 arranged on the surface of the vibration element 2.

[0011] The vibrating element 2 is an AT-cut quartz crystal substrate. However, the vibrating element 2 is not limited to an AT-cut quartz crystal substrate. An AT-cut quartz crystal substrate has a thickness-shear vibration mode and a third-order frequency-temperature characteristic. Therefore, the vibrating element 1 has excellent temperature characteristics. An AT-cut quartz crystal substrate is a quartz crystal substrate cut along a plane obtained by rotating the XZ plane approximately 35°15' around the X axis, where the electrical axis, mechanical axis, and optical axis, which are the crystal axes of the quartz, are the X axis, Y axis, and Z axis.

[0012] The Y-axis and Z-axis rotated around the X-axis are referred to as the Y'-axis and Z'-axis, and for ease of explanation, the X-axis, Y'-axis, and Z'-axis are illustrated in each drawing. As in the oscillator 100 of a third embodiment described later, the vibration element 1 is supported at the end opposite to the arrow in the X-axis direction. Therefore, for ease of explanation, the arrow side in the X-axis direction will be referred to as the "tip side" of the vibration element 1, and the opposite side will be referred to as the "base side" of the vibration element 1. For ease of explanation, the arrow side in the Y'-axis direction will be referred to as the bottom side, and the opposite side will be referred to as the top side.

[0013] As shown in FIGS. 1 and 2, the vibrating element 2 is plate-shaped and has an upper surface 2a as a first surface and a lower surface 2b as a second surface, which are opposite surfaces. When viewed from the thickness direction, i.e., the Y'-axis direction, the vibrating element 2 has a substantially pentagonal shape with the X-axis direction as the longitudinal direction and the Z'-axis direction as the lateral direction, with one corner located on the tip side cut off. By giving the vibrating element 2 this shape, the weight of the tip of the vibrating element 1 can be reduced. Therefore, deflection and vibration of the tip when subjected to an impact are suppressed, resulting in a vibrating element 1 with excellent impact resistance. However, the shape of the vibrating element 2 is not particularly limited. For example, the corner located on the tip side may not be cut off, and the vibrating element 1 may have a substantially rectangular shape.

[0014] 1 to 3, a recessed portion 20 that opens to the upper surface 2a is formed at the tip of the vibrating element 2. Therefore, the vibrating element 2 has a first region 21 that is thinned by the recessed portion 20, and a second region 22 that is located around the first region 21 and is thicker than the first region 21. Then, as will be described later, first and second excitation electrodes 31 and 32 are arranged on both sides of the first region 21, and the portion of the first region 21 sandwiched between the first and second excitation electrodes 31 and 32 becomes a vibrating portion 211.

[0015] That is, the vibrating element 1 has a so-called "inverted mesa structure." Such an inverted mesa structure can increase the oscillation frequency of the vibrating element 1 while maintaining sufficient strength of the vibrating element 1. However, the vibrating element 2 is not limited to this. For example, the recessed portion 20 may be formed not only on the upper surface 2a but also on the lower surface 2b. Also, for example, the vibrating element 2 may have a so-called "mesa structure" in which the first region 21 is thicker than the second region 22, or the entire vibrating element 2 may have a flat plate structure with a uniform thickness. Furthermore, the vibrating element 2 may be subjected to convex processing or bevel processing.

[0016] 1 and 2, the second region 22 of the vibrating element 2 is provided with a first no-electrode region S1, a second no-electrode region S2, a third no-electrode region S3, a fourth no-electrode region S4, and a fifth no-electrode region S5, which are not formed with the electrode pattern 3. These first to fifth no-electrode regions S1 to S5 will be described in the description of the electrode pattern 3.

[0017] Next, we will explain the electrode pattern 3. The electrode pattern 3 is formed by depositing a metal film over the entire surface of the vibrating bar 2 using various film-forming techniques such as sputtering and vapor deposition, and then patterning the deposited metal film into a desired shape using photolithography and etching techniques. However, the method for forming the electrode pattern 3 is not particularly limited.

[0018] 1 and 2, the electrode pattern 3 is arranged so as to avoid the first no-electrode region S1, the second no-electrode region S2, the third no-electrode region S3, the fourth no-electrode region S4, and the fifth no-electrode region S5, as described above. Such an electrode pattern 3 has an upper surface-side electrode pattern 3a arranged on the upper surface 2a and consisting of a first excitation electrode 31, a first pad electrode 33, and a first extraction electrode 35, and a lower surface-side electrode pattern 3b arranged on the lower surface 2b and consisting of a second excitation electrode 32, a second pad electrode 34, and a second extraction electrode 36.

[0019] 1 and 2, the first excitation electrode 31 is disposed on the upper surface 2a of the first region 21. The first pad electrode 33 is disposed not only on the upper surface 2a of the second region 22 but also on the lower surface 2b via a side surface. The first excitation electrode 31 and the first pad electrode 33 are electrically connected via a first extraction electrode 35 disposed on the upper surface 2a.

[0020] Similarly, the second excitation electrode 32 is disposed on the lower surface 2b of the first region 21 so as to face the first excitation electrode 31. As described above, the portion of the first region 21 sandwiched between the first and second excitation electrodes 31, 32 forms the vibration portion 211. The second pad electrode 34 is disposed not only on the lower surface 2b of the second region 22 but also on the upper surface 2a via a side surface. The second excitation electrode 32 and the second pad electrode 34 are electrically connected via a second extraction electrode 36 disposed on the lower surface 2b.

[0021] The first pad electrode 33 and the second pad electrode 34 are arranged side by side in the Z'-axis direction at the base end of the vibrating element 2 so as not to contact each other. The upper surface side electrode pattern 3a is formed so as to be biased overall toward the arrow in the Z'-axis direction, while the lower surface side electrode pattern 3b is formed so as to be biased overall toward the opposite side of the arrow in the Z'-axis direction. As a result, a space is formed between the first extracted electrode 35 and the second extracted electrode 36.

[0022] The electrode pattern 3 further has an inductor pattern 30 disposed in the space and functioning as an inductor. As shown in Figures 1 to 3, the inductor pattern 30 has a spiral first electrode pattern 37 disposed on the upper surface 2a of the second region 22, a spiral second electrode pattern 38 disposed on the lower surface 2b of the second region 22 so as to overlap with the first electrode pattern 37 in a plan view, and a through electrode 39 that penetrates the vibrator element 2 and electrically connects the first electrode pattern 37 and the second electrode pattern 38.

[0023] In this way, by having the inductor pattern 30 include the first and second electrode patterns 37 and 38, an inductor with a large number of windings can be formed on the vibration element 1 without excessively increasing the size of the vibration element 1. In this embodiment, the first electrode pattern 37 and the second electrode pattern 38 are designed to have the same inner diameter, outer diameter, line width, winding pitch, etc. However, this is not limited thereto, and at least one of the above conditions may be different from each other. In this embodiment, the spiral shapes of the first and second electrode patterns 37 and 38 are substantially rectangular, but these shapes are not particularly limited thereto and may be, for example, hexagonal, octagonal, circular, elliptical, etc.

[0024] As shown in FIG. 1 , the first electrode pattern 37 is formed by being wound spirally so as to surround the first no-electrode region S1 in a plan view from the Y′-axis direction. In other words, the first no-electrode region S1 is located inside the first electrode pattern 37. The first electrode pattern 37 is electrically connected to the first extraction electrode 35 at its outer peripheral end and electrically connected to the through electrode 39 at its inner peripheral end. Similarly, the second electrode pattern 38 is formed by being wound spirally so as to surround the first no-electrode region S1 in a plan view from the Y′-axis direction. In other words, the first no-electrode region S1 is located inside the second electrode pattern 38. The second electrode pattern 38 is electrically connected to the second extraction electrode 36 at its outer peripheral end and electrically connected to the through electrode 39 at its inner peripheral end. Therefore, in this embodiment, the inductor pattern 30 is connected in parallel to the vibration element 1.

[0025] Such an inductor pattern 30 is an inductance inserted into the oscillation loop of the oscillation circuit, and is generally referred to as an elongated coil or simply as a coil. In this embodiment, as described above, the inductance due to the inductor pattern 30 is configured to be connected in parallel with the vibration element 1. Therefore, when the inductor pattern 30 is mounted on, for example, an oscillator 100 such as that of the third embodiment described later, it is possible to cancel the stray capacitance between the electrodes in the oscillation circuit.

[0026] In particular, in the vibration element 1, the first and second electrode patterns 37, 38 are arranged around the first no-electrode region S1, so that the central axis J of the magnetic flux Q generated in the inductor pattern 30 intersects with the first no-electrode region S1, as shown in FIG. 4. Therefore, the magnetic flux Q generated in the inductor pattern 30 passes through the first no-electrode region S1, making it difficult for eddy currents to be generated in the electrode pattern 3, and eddy current loss can be suppressed. Therefore, an inductance with a high Q value can be realized. Furthermore, since an inductance with a high Q value can be realized, the inductor pattern 30 can be made smaller, which contributes to the miniaturization of the vibration element 1.

[0027] The width W1 of the first no-electrode region S1 is not particularly limited, but when the winding pitch of the first electrode pattern 37 is P, it is preferable that W1≧P, and more preferably W1≧2P. This allows the first no-electrode region S1 to be sufficiently large, and the above-mentioned effects can be more reliably achieved. On the other hand, the upper limit of the width W1 is not particularly limited, but from the viewpoint of preventing the vibration element 1 from becoming excessively large, it is preferable that W≦100P, and more preferably W1≦50P. The width W1 can be rephrased as the diameter of a circle E inscribed in the first electrode pattern 37, for example.

[0028] As shown in FIG. 1, in a plan view from the Y'-axis direction, a fourth no-electrode region S4 and a fifth no-electrode region S5, where no electrode pattern 3 exists, are formed between the first electrode pattern 37 on the upper surface 2a and the lower-surface-side electrode pattern 3b on the lower surface 2b. The fourth no-electrode region S4 is formed between the first electrode pattern 37 and the second pad electrode 34, and the fifth no-electrode region S5 is formed between the first electrode pattern 37 and the second extraction electrode 36. By providing these fourth and fifth no-electrode regions S4 and S5, as shown in FIG. 4, magnetic flux Q generated in the inductor pattern 30 passes through the fourth and fifth no-electrode regions S4 and S5, making it difficult for eddy currents to be generated in the electrode pattern 3, thereby suppressing eddy current loss. This allows for an inductance with a high Q value to be achieved.

[0029] The width W4 of the fourth no-electrode region S4 is not particularly limited, but preferably W4≧P, and more preferably W4≧2P. This allows the fourth no-electrode region S4 to be sufficiently large, and the above-mentioned effects can be more reliably achieved. On the other hand, the upper limit of the width W4 is not particularly limited, but from the viewpoint of preventing the vibration element 1 from becoming excessively large, it is preferable that W4≦100P, and more preferably W4≦50P. The width W4 means, for example, the minimum distance between the first electrode pattern 37 and the second pad electrode 34 in a planar view from the Y′-axis direction.

[0030] Furthermore, the width W5 of the fifth no-electrode region S5 is not particularly limited, but preferably W5≧P, and more preferably W5≧2P. This allows the fifth no-electrode region S5 to be sufficiently large, and the above-mentioned effects can be more reliably achieved. On the other hand, the upper limit of the width W5 is not particularly limited, but from the viewpoint of preventing the vibration element 1 from becoming excessively large, it is preferable that W5≦100P, and more preferably W5≦50P. Note that the width W5 means, for example, the minimum distance between the first electrode pattern 37 and the second extraction electrode 36 in a plan view from the Y′-axis direction.

[0031] As shown in FIG. 2 , in a plan view from the Y′-axis direction, a second no-electrode region S2 and a third no-electrode region S3, where no electrode pattern 3 exists, are formed between the second electrode pattern 38 on the lower surface 2b side and the upper surface electrode pattern 3a on the upper surface 2a side. The second no-electrode region S2 is formed between the second electrode pattern 38 and the first pad electrode 33, and the third no-electrode region S3 is formed between the second electrode pattern 38 and the first extraction electrode 35. By providing these second and third no-electrode regions S2 and S3, as shown in FIG. 4 , magnetic flux Q generated in the inductor pattern 30 passes through the second and third no-electrode regions S2 and S3, making it difficult for eddy currents to be generated in the electrode pattern 3, thereby suppressing eddy current loss. This allows for an inductance with a high Q value to be achieved. In this embodiment, the first electrode pattern 37 and the second electrode pattern 38 overlap in a plan view, so the second no-electrode region S2 can also be said to be formed between the first electrode pattern 37 and the first pad electrode 33. Similarly, it can be said that the third no-electrode region S3 is formed between the first electrode pattern 37 and the first extraction electrode .

[0032] The width W2 of the second no-electrode region S2 is not particularly limited, but is preferably approximately the same as the width W4 of the fourth no-electrode region S4. This ensures that the second no-electrode region S2 is sufficiently large, and the above-mentioned effects can be more reliably achieved. Furthermore, excessive size increase of the vibration element 1 can be suppressed. The width W2 refers to, for example, the minimum distance between the second electrode pattern 38 and the first pad electrode 33 in a planar view from the Y'-axis direction. In this embodiment, the width W2 also refers to the minimum distance between the first electrode pattern 37 and the first pad electrode 33 in a planar view from the Y'-axis direction.

[0033] Furthermore, the width W3 of the third no-electrode region S3 is not particularly limited, but is preferably approximately the same as the width W5 of the fifth no-electrode region S5. This ensures that the third no-electrode region S3 is sufficiently large, and the above-mentioned effects can be more reliably achieved. Furthermore, excessive size increase of the vibration element 1 can be suppressed. Note that the width W3 means, for example, the minimum distance between the second electrode pattern 38 and the first extraction electrode 35 in a planar view from the Y'-axis direction. In this embodiment, the width W3 also means the minimum distance between the first electrode pattern 37 and the first extraction electrode 35 in a planar view from the Y'-axis direction.

[0034] The above describes the vibration element 1. As described above, the vibration element 1 includes a vibrating element 2 having an upper surface 2a as a first surface and a lower surface 2b as a second surface, which are opposite surfaces. The vibrating element 1 includes a first no-electrode region S1 and an electrode pattern 3 arranged on the vibrating element 2 to avoid the first no-electrode region S1. The electrode pattern 3 includes a first excitation electrode 31 arranged on the upper surface 2a, a second excitation electrode 32 arranged on the lower surface 2b facing the first excitation electrode 31, and a spiral first electrode pattern 37 arranged on the upper surface 2a and surrounding the first no-electrode region S1. The first no-electrode region S1 intersects with the central axis J of the magnetic flux Q generated in the first electrode pattern 37. This configuration makes it difficult for the magnetic flux Q generated in the first electrode pattern 37 to pass through the electrode pattern 3, thereby suppressing eddy current loss. This allows for an inductance with a high Q value to be achieved. Furthermore, since an inductance with a high Q value can be realized, the inductor pattern 30 can be made smaller, which contributes to making the vibration element 1 smaller.

[0035] As described above, the width W1 of the first no-electrode region S1 is equal to or greater than the winding pitch P of the first electrode pattern 37. This ensures that the first no-electrode region S1 is sufficiently large, and eddy current loss can be more effectively suppressed.

[0036] As described above, the electrode pattern 3 includes the second electrode pattern 38, which is arranged on the lower surface 2b, has a spiral shape surrounding the first no-electrode region S1, and is electrically connected to the first electrode pattern 37, and the first pad electrode 33, which is arranged on the upper surface 2a and is electrically connected to the first excitation electrode 31. The vibrator element 2 also includes a second no-electrode region S2 in which no electrode pattern 3 is arranged between the second electrode pattern 38 and the first pad electrode 33 in a plan view of the vibrator element 2. Therefore, even around the second electrode pattern 38, the magnetic flux Q generated in the second electrode pattern 38 is less likely to pass through the electrode pattern 3, and eddy current loss can be more effectively suppressed.

[0037] As described above, the width W2 of the second no-electrode region S2 is equal to or greater than the winding pitch P of the first electrode pattern 37. This ensures that the second no-electrode region S2 is sufficiently large, and eddy current loss can be more effectively suppressed.

[0038] As described above, the electrode pattern 3 has the first extraction electrode 35 disposed on the upper surface 2a and electrically connecting the first excitation electrode 31 and the first pad electrode 33. The vibrator element 2 also has a third no-electrode region S3 in which the electrode pattern 3 is not disposed between the second electrode pattern 38 and the first extraction electrode 35 in a plan view of the vibrator element 2. Therefore, even around the second electrode pattern 38, the magnetic flux Q generated in the second electrode pattern 38 is less likely to pass through the electrode pattern 3, and eddy current loss can be more effectively suppressed.

[0039] As described above, the width W3 of the third no-electrode region S3 is equal to or greater than the winding pitch P of the first electrode pattern 37. This ensures that the third no-electrode region S3 is sufficiently large, and eddy current loss can be more effectively suppressed.

[0040] As described above, the electrode pattern 3 has a second pad electrode 34 that is disposed on the lower surface 2b and electrically connected to the second excitation electrode 32. The vibrator element 2 also has a fourth no-electrode region S4 in which the electrode pattern 3 is not disposed between the first electrode pattern 37 and the second pad electrode 34 in a plan view of the vibrator element 2. Therefore, even around the first electrode pattern 37, the magnetic flux Q generated in the first electrode pattern 37 is less likely to pass through the electrode pattern 3, and eddy current loss can be more effectively suppressed.

[0041] As described above, the width W4 of the fourth no-electrode region S4 is equal to or greater than the winding pitch P of the first electrode pattern 37. This ensures that the fourth no-electrode region S4 is sufficiently large, and eddy current loss can be suppressed more effectively.

[0042] As described above, the electrode pattern 3 has the second extraction electrode 36 that is disposed on the lower surface 2b and electrically connects the second excitation electrode 32 and the second pad electrode 34. The vibrator element 2 also has a fifth no-electrode region S5 in which no electrode pattern 3 is disposed between the first electrode pattern 37 and the second extraction electrode 36 in a plan view of the vibrator element 2. Therefore, even around the first electrode pattern 37, the magnetic flux Q generated in the first electrode pattern 37 is less likely to pass through the electrode pattern 3, and eddy current loss can be more effectively suppressed.

[0043] As described above, the width W5 of the fifth no-electrode region S5 is equal to or greater than the winding pitch P of the first electrode pattern 37. This ensures that the fifth no-electrode region S5 is sufficiently large, and eddy current loss can be suppressed more effectively.

[0044] Although the vibration element 1 of this embodiment has been described above, the vibration element 1 is not limited to this. For example, the second electrode pattern 38 may be omitted from the inductor pattern 30 depending on the required inductance value.

[0045] Second Embodiment Fig. 5 is a top view of the vibration element according to the second embodiment, and Fig. 6 is a bottom view of the vibration element shown in Fig. 5.

[0046] The vibration element 1 of this embodiment is similar to the vibration element 1 of the first embodiment described above, except that the inductor pattern 30 is connected in series to the vibration element 1. Therefore, in the following description, the differences between this embodiment and the first embodiment described above will be mainly described, and a description of similar points will be omitted. Furthermore, in each drawing of this embodiment, the same reference numerals are used to designate the same components as those in the above-described embodiment.

[0047] 5 and 6, in the vibrator element 1 of this embodiment, the inductor pattern 30 is connected to the middle of the first extraction electrode 35. Specifically, the first extraction electrode 35 has a first branch 351 that is disposed on the upper surface 2a and has one end connected to the first excitation electrode 31, and a second branch 352 that is disposed on the lower surface 2b and has one end connected to the first pad electrode 33, and the first branch 351 and the second branch 352 are connected to each other via the inductor pattern 30.

[0048] In this manner, in this embodiment, the inductance due to the inductor pattern 30 is connected in series with the vibration element 1. Therefore, for example, it is possible to increase the frequency variable range of an oscillator incorporating the vibration element 1.

[0049] The second embodiment as described above can also achieve the same effects as the first embodiment.

[0050] <Third embodiment> Fig. 7 is a cross-sectional view showing an oscillator according to a third embodiment. Fig. 8 is a top view of the oscillator shown in Fig. 7. Fig. 9 is a circuit diagram showing an example of a circuit included in a circuit element. Fig. 10 is a circuit diagram explaining an example of an equivalent circuit of a vibration unit.

[0051] 7 and 8 includes a vibration element 1, a circuit element 8 including an oscillation circuit 80 that causes the vibration element 1 to oscillate, and a package 9 that houses the vibration element 1 and the circuit element 8. The package 9 also includes a base 91 having a recess 911 that opens on its upper surface, and a plate-shaped lid 92 that is bonded to the upper surface of the base 91 via a bonding member 93 so as to close the opening of the recess 911. An airtight internal space is formed inside the package 9 by the recess 911, and the vibration element 1 and the circuit element 8 are housed in this internal space.

[0052] For example, the base 91 is made of a ceramic such as alumina, and the lid 92 is made of a metal material such as Kovar. However, the materials for the base 91 and the lid 92 are not particularly limited. The internal space is in a reduced pressure state, preferably a state closer to a vacuum. This reduces viscous resistance and improves the vibration characteristics of the vibration element 1. However, the atmosphere in the internal space is not particularly limited.

[0053] The recess 911 has a first recess 911a that opens to the top surface of the base 91, and a second recess 911b that opens to the bottom surface of the first recess 911a and is smaller than the first recess 911a. The circuit element 8 is disposed on the bottom surface of the second recess 911b, and the vibration element 1 is disposed on the bottom surface of the first recess 911a. The vibration element 1 is fixed to the bottom surface of the first recess 911a in the second region 22. The second region 22 is thicker than the first region 21, so the fixed state is more stable.

[0054] Furthermore, a plurality of internal terminals 951 electrically connected to the circuit element 8 via a conductive bonding member B1 are arranged on the bottom surface of the second recess 911b, a plurality of internal terminals 952 electrically connected to the vibration element 1 via a conductive bonding member B2 are arranged on the bottom surface of the first recess 911a, and a plurality of external terminals 953 are arranged on the lower surface of the base 91. Some of the plurality of internal terminals 951 are connected to the external terminals 953 via internal wiring (not shown), and the remaining some are connected to the internal terminals 952 via internal wiring (not shown). This electrically connects the vibration element 1 and the circuit element 8, and electrically connects the circuit element 8 and the external terminals 953.

[0055] 9 is an example of a circuit diagram of oscillator 100, which includes an amplifier 81, capacitors 82 and 83, a variable capacitance diode 84, a control voltage input terminal 85, a control voltage application resistor 86, and a frequency output terminal 87 of the voltage-controlled crystal oscillator. As can be seen from this circuit diagram, oscillator 100 is configured such that inductance due to inductor pattern 30 is connected in parallel with vibrating element 1 (vibrating portion 211). Therefore, stray capacitance between each electrode in oscillation circuit 80 can be canceled.

[0056] 10, a typical equivalent circuit of the vibrating part 211 is represented by a circuit in which an equivalent series inductance 71, an equivalent series capacitance 72, and an equivalent series resistance 73 are connected in series, and an equivalent parallel capacitance 74 is connected in parallel to these. The inductor pattern 30 can cancel the stray capacitance including the equivalent parallel capacitance 74.

[0057] In addition, when the equivalent parallel capacitance 74 is C0 and the equivalent series capacitance 72 is C1, it is preferable that C0 / C1 is small. This makes it possible to widen the frequency range. Furthermore, when the vibration frequency of the vibration element 1 is ω and the inductance of the inductor pattern 30 is L, it is preferable to set L in the range of ωC0>1 / (ωL). This makes it possible to cancel the influence of C0.

[0058] The above has described the oscillator 100. As described above, such an oscillator 100 has the vibration element 1, the circuit element 8 that causes the vibration element 1 to oscillate, and the package 9 that houses the vibration element 1 and the circuit element 8. This makes it possible to enjoy the effects of the vibration element 1 described above, resulting in a highly reliable oscillator 100.

[0059] As described above, in the vibration element 1, the thickness of the first region 21 where the first excitation electrode 31 and the second excitation electrode 32 are provided is thinner than the thickness of the second region 22 where the first electrode pattern 37 is provided. This allows the oscillation frequency of the vibration element 1 to be increased.

[0060] As described above, the vibration element 1 is fixed to the package 9 in the second region 22. The second region 22 is thicker than the first region 21, and therefore the fixed state is more stable.

[0061] The third embodiment as described above can also achieve the same effects as the first embodiment.

[0062] Although the vibration element and oscillator of the present invention have been described above based on the illustrated embodiments, the present invention is not limited thereto, and the configuration of each part can be replaced with any configuration having a similar function. Furthermore, any other configuration may be added to the present invention. Furthermore, the above-described embodiments may be combined as appropriate. [Explanation of symbols]

[0063] 1...vibration element, 100...oscillator, 2...vibration piece, 2a...upper surface, 2b...lower surface, 20...recessed portion, 21...first region, 211...vibration portion, 22...second region, 3...electrode pattern, 3a...upper surface electrode pattern, 3b...lower surface electrode pattern, 30...inductor pattern, 31...first excitation electrode, 32...second excitation electrode, 33...first pad electrode, 34...second pad electrode, 35...first extraction electrode, 351...first division portion, 352...second division portion, 36...second extraction electrode, 37...first electrode pattern, 38...second electrode pattern, 39...through electrode, 71...equivalent series inductance, 72...equivalent series capacitance, 73...equivalent series resistance, 74...equivalent parallel capacitance, 8...circuit element, 80...oscillating element Resonance circuit, 81...amplifier, 82...capacitor, 83...capacitor, 84...variable capacitance diode, 85...control voltage input terminal, 86...resistor for applying control voltage, 87...frequency output terminal, 9...package, 91...base, 911...recess, 911a...first recess, 911b...second recess, 92...lid, 93...bonding member, 951...internal terminal, 952...internal terminal, 953...external terminal, B1...bonding member, B2...bonding member, E...circle, J...center axis, P...winding pitch, Q...magnetic flux, S1...first no-electrode area, S2...second no-electrode area, S3...third no-electrode area, S4...fourth no-electrode area, S5...fifth no-electrode area, W1...width, W2...width, W3...width, W4...width, W5...width

Claims

1. a vibrating element having a first surface and a second surface that are opposite surfaces and a first no-electrode region; an electrode pattern disposed on the vibrating element to avoid the first no-electrode region, The electrode pattern is a first excitation electrode disposed on the first surface; a second excitation electrode disposed on the second surface so as to face the first excitation electrode; a spiral first electrode pattern disposed on the first surface and surrounding the first no-electrode region; a second electrode pattern disposed on the second surface, spirally surrounding the first no-electrode region, and electrically connected to the first electrode pattern; a first pad electrode disposed on the first surface and electrically connected to the first excitation electrode; a second pad electrode disposed on the second surface and electrically connected to the second excitation electrode; the first no-electrode region intersects with a central axis of a magnetic flux generated in the first electrode pattern, The vibrator element has a second no-electrode region in which the electrode pattern is not disposed between the second electrode pattern and the first pad electrode in a plan view of the vibrator element; a fourth no-electrode region in which the electrode pattern is not disposed between the first electrode pattern and the second pad electrode in a plan view of the resonator element, A vibration element, characterized in that the width of the second no-electrode region and the width of the fourth no-electrode region are the same.

2. The vibration element according to claim 1 , wherein the width of the first no-electrode region is equal to or greater than the winding pitch of the first electrode pattern.

3. The vibration element according to claim 1 , wherein the width of the second no-electrode region is equal to or greater than the winding pitch of the first electrode pattern.

4. the electrode pattern has a first extraction electrode disposed on the first surface and electrically connecting the first excitation electrode and the first pad electrode; A vibration element as described in any one of claims 1 to 3, wherein the vibration piece has a third electrodeless area in which the electrode pattern is not arranged between the second electrode pattern and the first extraction electrode when viewed in a plane of the vibration piece.

5. The vibration element according to claim 4 , wherein the width of the third no-electrode region is equal to or greater than the winding pitch of the first electrode pattern.

6. the electrode pattern has a second extraction electrode disposed on the second surface and electrically connecting the second excitation electrode and the second pad electrode; A vibration element described in any one of claims 1 to 5, wherein the vibration piece has a fifth no-electrode area in which the electrode pattern is not arranged between the first electrode pattern and the second extraction electrode when viewed in a plane of the vibration piece.

7. The vibration element according to claim 6 , wherein the width of the fifth no-electrode region is equal to or greater than the winding pitch of the first electrode pattern.

8. The vibration element according to any one of claims 1 to 7, a circuit element that causes the vibration element to oscillate; and a package that accommodates the vibration element and the circuit element.

9. The oscillator according to claim 8 , wherein the thickness of a first region in which the first excitation electrode and the second excitation electrode are provided is thinner than the thickness of a second region in which the first electrode pattern is provided.

10. The oscillator according to claim 9 , wherein the vibration element is fixed to the package in the second region.

Images