JP6816805B2 - Vibrating elements, oscillators, oscillators, electronic devices and mobiles - Google Patents

Description

The present invention relates to vibrating elements, oscillators, oscillators, electronic devices and mobile objects.

Conventionally, a vibrating element using quartz has been known (see, for example, Patent Document 1). Such a vibrating element is widely used as a reference frequency source or a transmission source of various electronic devices because of its excellent frequency / temperature characteristics.
The vibrating element described in Patent Document 1 has a tuning fork shape, and has a base portion and a pair of vibrating arms extending from the base portion. Further, each vibrating arm is formed with a pair of grooves that open on the upper surface and the lower surface thereof. Therefore, each vibrating arm has a substantially H-shaped cross-sectional shape. By forming the vibrating arm in such a shape, the thermoelastic loss can be reduced and excellent vibration characteristics can be exhibited. However, conventionally, the shape (including the size) of the vibrating arm around the groove has not been sufficiently studied.

Square root extraction No. 2-322229

An object of the present invention is to provide a vibrating element capable of exhibiting excellent vibration characteristics with low power consumption, and an oscillator, an oscillator, an electronic device and a moving body including the vibrating element.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following application example.
[Application example 1]
The vibrating element of the present invention includes a first end portion and a base portion including a second end portion opposite to the first end portion in a plan view.
It is provided integrally with the base portion, extends from the base portion along the first direction on the first end side side of the base portion, and is arranged along a second direction orthogonal to the first direction. Including a pair of vibrating arms
Each of the vibrating arms
With the arm
Includes a wide portion of the arm that is located on the opposite side of the base from the base and that is longer than the arm in the second direction.
Each of the vibrating arms
A pair of main surfaces that are in a front-to-back relationship,
Including a bottomed groove provided on each of the main surfaces,
The main surface of each of the arms is characterized in that the width of each portion arranged with the groove in between along the second direction is 6 μm or less.
As a result, the equivalent series resistance R1 (CI value) can be sufficiently lowered while maintaining the Q value of the vibrating element relatively high. As a result, it is possible to obtain a vibration element capable of exhibiting excellent vibration characteristics with low power consumption.

[Application example 2]
In the vibrating element of the present invention, the width is preferably 1 μm or more and 3 μm or less.
As a result, the R1 (CI value) of the vibrating element can be made smaller, and the vibrating element can be driven with lower power consumption.
[Application example 3]
In the vibrating element of the present invention, the maximum depth of the groove is t [μm].
When the thickness of the vibrating arm is T [μm],
It is preferable that η represented by 2t / T is 0.6 or more.
As a result, the forming area of the driving electrode can be increased, so that the R1 (CI value) of the vibrating element can be made smaller, and the vibrating element can be obtained with lower power consumption.
[Application example 4]
In the vibrating element of the present invention, the thickness of the vibrating arm is preferably 50 μm or more.
Thereby, R1 of the vibrating element can be made smaller.

[Application example 5]
The vibrating element of the present invention preferably includes a support portion that supports the base portion.
Thereby, the vibration leakage of the vibrating element can be reduced more effectively.
[Application example 6]
In the vibrating element of the present invention, the support portion preferably includes a support arm extending from the base portion along the first direction between the pair of vibrating arms.
Thereby, the vibration leakage of the vibrating element can be reduced more effectively.

[Application 7]
In the vibrating element of the present invention, the support portion preferably includes a support arm extending from the base portion on the second end side of the base portion.
Thereby, the vibration leakage of the vibrating element can be reduced more effectively. Further, since it is not necessary to provide a support arm between the vibrating arms, the length (width) of the vibrating element along the second direction can be reduced.

[Application Example 8]
In the vibrating element of the present invention, the support portion preferably includes at least the base portion, the vibrating arm, and a frame body that surrounds the vibrating arm and is connected to the support arm.
As a result, the vibrating element can be accurately fixed to, for example, the base of the package via the frame. Therefore, the size of the vibrating element can be increased, and as a result, its R1 can be made smaller.

[Application 9]
In the vibrating element of the present invention, the support portion preferably includes at least the base portion and a frame body surrounding the vibrating arm.
As a result, the vibrating element can be accurately fixed to, for example, the base of the package via the frame. Therefore, the size of the vibrating element can be increased, and as a result, its R1 can be made smaller.

[Application Example 10]
In the vibrating element of the present invention, the base portion has a length along the second direction between the pair of vibrating arms on at least one of the first end side and the second end side. It is preferable to include a narrowed portion that is continuously or gradually reduced toward the center of the base along the center line of the base.
Since the base portion has a narrowed width portion, vibration leakage of the vibrating element can be effectively suppressed.

[Application Example 11]
The oscillator of the present invention includes the vibrating element of the present invention and
It is characterized by including a package in which the vibrating element is mounted.
As a result, a highly reliable oscillator can be obtained.

[Application 12]
The oscillator of the present invention includes the vibrating element of the present invention and
It is characterized by including an oscillation circuit.
As a result, a highly reliable oscillator can be obtained.

[Application 13]
The electronic device of the present invention is characterized by including the vibrating element of the present invention.
As a result, a highly reliable electronic device can be obtained.
[Application 14]
The moving body of the present invention is characterized by including the vibrating element of the present invention.
As a result, a highly reliable moving body can be obtained.

It is a top view of the oscillator which concerns on 1st Embodiment of this invention. FIG. 5 is a cross-sectional view taken along the line AA in FIG. It is a top view explaining the principle of vibration leakage reduction. It is sectional drawing BB in FIG. It is sectional drawing of the vibrating arm explaining the heat conduction at the time of bending vibration. It is a graph which shows the relationship between a Q value and f / fm. It is sectional drawing which shows the vibrating arm formed by the wet etching. It is a graph which shows the relationship between W3 and Q value. It is a graph which shows the relationship between W3 and 1 / R1. It is a top view of the vibrating element which the oscillator which concerns on 2nd Embodiment of this invention has. It is a top view of the oscillator which concerns on 3rd Embodiment of this invention. FIG. 11 is a cross-sectional view taken along the line CC in FIG. It is a top view of the vibrating element which the oscillator which concerns on 4th Embodiment of this invention has. It is sectional drawing which shows the preferable embodiment of the oscillator of this invention. It is a perspective view which shows the structure of the mobile type (or notebook type) personal computer which applied the electronic device provided with the vibrating element of this invention. It is a perspective view which shows the structure of the mobile phone (including PHS) to which the electronic device provided with the vibration element of this invention is applied. It is a perspective view which shows the structure of the digital still camera to which the electronic device provided with the vibrating element of this invention is applied. It is a perspective view which shows typically the automobile as an example of the moving body of this invention.

Hereinafter, the vibrating element, the oscillator, the oscillator, the electronic device, and the moving body of the present invention will be described in detail based on the preferred embodiments shown in the drawings.
First, an oscillator to which the vibrating element of the present invention is applied (the oscillator of the present invention) will be described.

<First Embodiment>
1 is a plan view of the vibrator according to the first embodiment of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a plan view and a view for explaining the principle of vibration leakage reduction. 4 is a cross-sectional view taken along the line BB in FIG. 1, FIG. 5 is a cross-sectional view of a vibrating arm for explaining heat conduction during bending vibration, and FIG. 6 is a graph and a diagram showing the relationship between the Q value and f / fm. 7 is a cross-sectional view showing a vibrating arm formed by wet etching, FIG. 8 is a graph showing the relationship between W3 and the Q value, and FIG. 9 is a graph showing the relationship between W3 and 1 / R1. In the following, for convenience of explanation, as shown in FIG. 1, three axes orthogonal to each other are referred to as an X axis (electric crystal axis), a Y axis (mechanical axis of crystal), and a Z axis (optical axis of crystal). ..

1. 1. Oscillator The oscillator 1 shown in FIGS. 1 and 2 has a vibrating element 2 (vibrating element of the present invention) and a package 9 for accommodating the vibrating element 2. Hereinafter, the vibrating element 2 and the package 9 will be described in detail in order.
(Vibration element 2)
As shown in FIGS. 1, 2 and 4, the vibrating element 2 has a crystal substrate 3 and first and second drive electrodes 84 and 85 formed on the crystal substrate 3. Note that in FIGS. 1 and 2, for convenience of explanation, the first and second drive electrodes 84 and 85 are not shown.
The crystal substrate 3 is composed of a Z-cut crystal plate. As a result, the vibrating element 2 can exhibit excellent vibration characteristics. The Z-cut quartz plate is a quartz substrate whose thickness direction is the Z axis. The Z-axis preferably coincides with the thickness direction of the crystal substrate 3, but may be slightly tilted with respect to the thickness direction from the viewpoint of reducing the frequency temperature change in the vicinity of room temperature.

That is, when the tilt angle is θ degree (-5 degrees ≤ θ ≤ 15 degrees), the Cartesian coordinate system including the X axis as the electric axis of the crystal, the Y axis as the mechanical axis, and the Z axis as the optical axis. With the X-axis as the rotation axis, the Z-axis is tilted by θ degrees so that the + Z side rotates in the −Y direction of the Y-axis, and the Y-axis rotates in the + Z direction of the Z-axis. When the axis tilted by θ degrees is defined as the Y'axis, the thickness is the direction along the Z'axis, and the crystal substrate 3 has a surface including the X axis and the Y'axis as the main surface.

As shown in FIG. 1, the crystal substrate 3 has a base 4, a pair of vibrating arms 5, 6 extending from the base 4 and vibrating arms 5, 6 on the tip (first end) side of the base 4. A support arm (support portion) 71 extending from the base 4 is provided on the same side as these. Therefore, the base 4, the vibrating arms 5 and 6, and the support arm 71 are integrally formed.
The base portion 4 has a plate shape having an extension in the XY plane and a thickness in the Z-axis direction. The base portion 4 has a portion (main body portion 41) that supports and connects the vibrating arms 5 and 6 and a narrowed width portion 42 that reduces vibration leakage.

The narrowed width portion 42 is provided on the base end (second end portion) side of the main body portion 41, that is, on the side opposite to the side on which the vibrating arms 5 and 6 extend. Further, the width of the narrowed portion 42 (length along the X-axis direction) is along the center line C1 between the vibrating arms 5 and 6 from the vibrating arms 5 and 6, that is, the center of the base 4. It gradually decreases as it moves away from (main body 41), and its contour (edge) is arched (arc-shaped). By having such a narrowing portion 42, it is possible to effectively suppress the vibration leakage of the vibrating element 2.

The specific explanation is as follows. For the sake of simplicity, it is assumed that the shape of the vibrating element 2 is symmetrical with respect to a predetermined axis (center line C1) parallel to the Y axis.
First, as shown in FIG. 3A, a case where the narrowed width portion 42 is not provided will be described. When the vibrating arms 5 and 6 are bent and deformed so as to be separated from each other, a displacement close to a clockwise rotational motion occurs in the main body 41 near the connection of the vibrating arms 5, and vibration occurs. In the main body 41 near where the arm 6 is connected, a displacement close to a counterclockwise rotational motion occurs as shown by the arrow (however, since it is not a motion that can be called a rotational motion in a strict sense). , For the sake of convenience, "close to rotary motion").

Since the X-axis direction components of these displacements are oriented in opposite directions, they cancel each other out at the center of the main body 41 in the X-axis direction, and the displacement in the + Y-axis direction remains (however, strictly speaking, the Z-axis). The displacement in the direction remains, but it is omitted here). That is, the main body 41 is bent and deformed so that the central portion in the X-axis direction is displaced in the + Y-axis direction. Since the support arm 71 extends from the main body 41 having the displacement in the + Y axis direction and the support arm 71 performs the movement having the displacement in the + Y axis direction, an adhesive is formed on the support arm 71. When fixed to the package via an adhesive, the elastic energy associated with the + Y-axis displacement leaks to the outside via the adhesive. This is a loss called vibration leakage, which causes deterioration of the Q value, resulting in deterioration of the CI value.

On the other hand, as shown in FIG. 3B, when the narrowed width portion 42 is provided, the narrowed width portion 42 has an arch-shaped (curved) contour, so that the rotation described above is performed. Displacements close to motion will stagger each other at the narrowed portion 42. That is, in the central portion in the X-axis direction of the narrowed width portion 42, the displacement in the X-axis direction is canceled as in the central portion in the X-axis direction of the main body portion 41, and at the same time, the displacement in the Y-axis direction is suppressed. Become. Further, since the contour of the narrowed width portion 42 is arched, the displacement in the + Y axis direction that is likely to occur in the main body portion 41 is also suppressed. As a result, the displacement of the central portion in the X-axis direction of the base portion 4 in the + Y-axis direction when the narrowed width portion 42 is provided is much smaller than that when the narrowed width portion 42 is not provided. That is, it is possible to obtain a vibration element having a small vibration leakage.

Here, the contour of the narrowed portion 42 has an arch shape, but the present invention is not limited to this as long as it exhibits the above-mentioned action. For example, in a plan view, the width gradually decreases along the center line C1, and the contour is formed in a stepped shape (step shape) by a plurality of straight lines. In a plan view, the width is along the center line C1. It becomes smaller linearly (continuously), and the contour is formed in a mountain shape (triangular shape) by two straight lines, and the width is linear (continuous) along the center line C1 in a plan view. It may be a narrowed portion or the like that becomes smaller and has a contour formed by three or more straight lines.

The vibrating arms 5 and 6 are aligned in the X-axis direction (second direction) and extend from the tip of the base 4 along the Y-axis direction (first direction) so as to be parallel to each other. Each of these vibrating arms 5 and 6 has a longitudinal shape, the base end thereof is a fixed end, and the tip end is a free end. Further, the vibrating arms 5 and 6 are provided at the arm portions 51 and 61 and the tips of the arm portions 51 and 61 (opposite to the base portion 4), respectively, and have a substantially rectangular hammer head (arm portion) in an XY plan view. Wide portions) 59 and 69 having a length longer along the X-axis direction than 51 and 61.

As shown in FIG. 4, the arm portion 51 includes a pair of main surfaces 511 and 512 formed of an XY plane and a pair of side surfaces 513 and 514 formed of a YZ plane and connecting the pair of main surfaces 511 and 512. have. Further, the arm portion 51 has a bottomed groove 52 that opens to the main surface 511 and a bottomed groove 53 that opens to the main surface 512. Each of the grooves 52 and 53 extends in the Y-axis direction, the tip is located at the boundary between the arm 51 and the hammer head 59, and the base end is located at the base 4. Such an arm portion 51 has a substantially H-shaped cross-sectional shape at a portion where the grooves 52 and 53 are formed.

By forming the grooves 52 and 53 in the vibrating arm 5 in this way, the thermoelastic loss can be reduced and excellent vibration characteristics can be exhibited (described in detail later). The lengths of the grooves 52 and 53 are not limited, and the tips of the grooves 52 and 53 may be located at the boundary between the arm portion 51 and the hammer head 59 as in the present embodiment. If the tips of the grooves 52 and 53 are configured to extend to the hammer head 59, the stress concentration generated around the tips of the grooves 52 and 53 is relaxed, so that there is a risk of breakage or chipping that occurs when an impact is applied. Decrease. Alternatively, if the tips of the grooves 52 and 53 are located closer to the base than in the present embodiment, the stress concentration generated near the boundary between the arm 51 and the hammer head 59 is relaxed, so that an impact is applied. The risk of breakage or chipping that occurs at the time is reduced.

Further, since the base ends of the grooves 52 and 53 extend to the base portion 4, the stress concentration at the boundary portion thereof is relaxed. Therefore, the risk of breakage or chipping that occurs when an impact is applied is reduced. Alternatively, if the base ends of the grooves 52 and 53 are located in the Y-axis direction (the direction in which the vibrating arm 5 extends) from the boundary between the base 4 and the arm 51, near the boundary between the base 4 and the arm 51. Since the stress concentration that occurs is alleviated, the risk of breakage or chipping that occurs when an impact is applied is reduced.

In the grooves 52 and 53, the positions of the grooves 52 and 53 are adjusted in the X-axis direction with respect to the position of the vibrating arm 5 so that the center of gravity of the cross section of the vibrating arm 5 coincides with the center of the cross-sectional shape of the vibrating arm 5. It is preferably formed. By doing so, unnecessary vibration of the vibrating arm 5 (specifically, oblique vibration having an out-of-plane component) is reduced, so that vibration leakage can be reduced. Further, in this case, since it is possible to reduce the occurrence of unnecessary vibration, the drive region can be relatively increased and the CI value can be reduced.
Further, it is preferable that the center of the hammer head 59 in the X-axis direction is slightly deviated from the center of the vibrating arm 5 in the X-axis direction. By doing so, it is possible to reduce the vibration of the base portion 4 in the Z-axis direction caused by the vibrating arm 5 twisting during bending vibration, so that vibration leakage can be suppressed.

The vibrating arm 5 has been described above. The vibrating arm 6 has the same configuration as the vibrating arm 5. That is, the arm portion 61 has a pair of main surfaces 611 and 612 formed of an XY plane and a pair of side surfaces 613 and 614 formed of a YZ plane and connecting the pair of main surfaces 611 and 612. .. Further, the arm portion 61 has a bottomed groove 62 that opens to the main surface 611 and a bottomed groove 63 that opens to the main surface 612. Each of the grooves 62 and 63 extends in the Y-axis direction, the tip thereof is located at the boundary between the arm portion 61 and the hammer head 69, and the base end is located at the base portion 4. Such an arm portion 61 has a substantially H-shaped cross-sectional shape at a portion where the grooves 62 and 63 are formed.
Further, it is preferable to slightly shift the center of the hammer head 69 in the X-axis direction from the center of the vibrating arm 6 in the X-axis direction. By doing so, it is possible to reduce the vibration of the base portion 4 in the Z-axis direction caused by the vibrating arm 6 twisting during bending vibration, so that vibration leakage can be suppressed.

As shown in FIG. 4, the vibrating arm 5 is formed with a pair of first drive electrodes 84 and a pair of second drive electrodes 85. Specifically, one of the first driving electrodes 84 is formed on the inner surface (side surface) of the groove 52, and the other is formed on the inner surface (side surface) of the groove 53. Further, one of the second driving electrodes 85 is formed on the side surface 513, and the other is formed on the side surface 514. Similarly, the vibrating arm 6 is also formed with a pair of first drive electrodes 84 and a pair of second drive electrodes 85. Specifically, one of the first driving electrodes 84 is formed on the side surface 613, and the other is formed on the side surface 614. Further, one of the second driving electrodes 85 is formed on the inner surface (side surface) of the groove 62, and the other is formed on the inner surface (side surface) of the groove 63.
When an alternating voltage is applied between these first and second drive electrodes 84 and 85, the vibrating arms 5 and 6 vibrate at a predetermined frequency in the in-plane direction (XY plane direction) so as to repeatedly approach and separate from each other. To do.

The configurations of the first and second drive electrodes 84 and 85 are not particularly limited, and gold (Au), gold alloy, platinum (Pt), aluminum (Al), aluminum alloy, silver (Ag), silver alloy, etc. Chromium (Cr), Chromium alloy, Nickel (Ni), Nickel alloy, Copper (Cu), Molybdenum (Mo), Niob (Nb), Tungsten (W), Iron (Fe), Titanium (Ti), Cobalt (Co) , Zinc (Zn), Zirconium (Zr) and other metal materials, and indium tin oxide (ITO) and other conductive materials.

As a specific configuration of the first and second drive electrodes 84 and 85, for example, an Au layer of 700 Å or less may be formed on a Cr layer of 700 Å or less. In particular, since Cr and Au have a large thermoelastic loss, the Cr layer and Au layer are preferably 200 Å or less. When increasing the dielectric breakdown resistance, the Cr layer and Au layer are preferably 1000 Å or more. Furthermore, since Ni is close to the coefficient of thermal expansion of quartz, by using a Ni layer as a base instead of the Cr layer, the thermal stress caused by the electrodes can be reduced, and the vibrating element 2 with good long-term reliability (aging characteristics) can be used. Can be obtained.

As described above, in the vibrating element 2, the thermoelastic loss is reduced by forming the grooves 52, 53, 62, 63 in the vibrating arms 5 and 6. Hereinafter, this will be specifically described by taking the vibrating arm 5 as an example.
As described above, the vibrating arm 5 bends and vibrates in the in-plane direction by applying an alternating voltage between the first and second driving electrodes 84 and 85. As shown in FIG. 5, during this bending vibration, when the side surface 513 of the arm 51 contracts, the side surface 514 expands, and conversely, when the side surface 513 expands, the side surface 514 contracts. When the vibrating arm 5 does not generate the Gough-Joule effect (energy elasticity is dominant over entropy elasticity), the temperature of the contracting surface side of the side surfaces 513 and 514 rises, and the temperature of the extending surface side increases. Since it descends, a temperature difference occurs between the side surface 513 and the side surface 514, that is, inside the arm portion 51. The heat conduction caused by such a temperature difference causes a loss of vibration energy, which lowers the Q value of the vibration element 2. The energy loss associated with such a decrease in the Q value is called thermoelastic loss.

In a vibrating element that vibrates in a bending vibration mode having a configuration like the vibrating element 2, when the bending vibration frequency (mechanical bending vibration frequency) f of the vibrating arm 5 changes, the bending vibration frequency of the vibrating arm 5 becomes the heat relaxation frequency fm. The Q value becomes the minimum when it matches with. The thermal relaxation frequency fm can be obtained by fm = 1 / (2πτ) (however, where π is the circular constant, if the e and Napier number, tau is the temperature difference by heat conduction e ^- is the relaxation time required to become ¹ times).

Further, if the heat relaxation frequency when the vibrating arm 5 is regarded as having a flat plate structure (a structure having a rectangular cross-sectional shape) is fm0, fm0 can be obtained by the following equation.
fm0 = πk / (2ρCpa ² ) ... (1)
In addition, π is the pi, k is the thermal conductivity in the vibration direction of the vibrating arm 5, ρ is the mass density of the vibrating arm 5, Cp is the heat capacity of the vibrating arm 5, and a is the width of the vibrating arm 5 in the vibration direction (effective). Width). When the constants of the material itself (that is, crystal) of the vibrating arm 5 are input to the thermal conductivity k, the mass density ρ, and the heat capacity Cp of the formula (1), the heat relaxation frequency fm0 obtained is the grooves 52 and 53 in the vibrating arm 5. It is the value when it is not provided.

In the vibrating arm 5, grooves 52 and 53 are formed so as to be located between the side surfaces 513 and 514. Therefore, the heat transfer path for balancing the temperature difference between the side surfaces 513 and 514 generated during the bending vibration of the vibrating arm 5 by heat conduction is formed so as to bypass the grooves 52 and 53, and the heat transfer path is formed on the side surfaces 513 and 514. It is longer than the straight line distance (shortest distance) between them. Therefore, the relaxation time τ becomes longer and the heat relaxation frequency fm becomes lower than in the case where the grooves 52 and 53 are not provided in the vibrating arm 5.

FIG. 6 is a graph showing the f / fm dependence of the Q value of the vibrating element in the bending vibration mode. In the figure, the curve F1 shown by the dotted line indicates a case where a groove is formed in the vibrating arm like the vibrating element 2 (when the cross-sectional shape of the vibrating arm is H-shaped), and is shown by a solid line. The curved line F2 shows a case where a groove is not formed in the vibrating arm (when the cross-sectional shape of the connecting arm is rectangular). As shown in the figure, the shapes of the curves F1 and F2 do not change, but the curve F1 shifts in the frequency decreasing direction with respect to the curve F2 as the heat relaxation frequency fm decreases as described above. Therefore, if the heat relaxation frequency when a groove is formed in the vibrating arm as in the vibrating element 2 is fm1, the vibration in which the groove is always formed in the vibrating arm by satisfying the following equation (2). The Q value of the element is higher than the Q value of the vibrating element in which the groove is not formed in the vibrating arm.

Further, if the relationship is limited to f / fm0> 1, a higher Q value can be obtained.
In FIG. 6, the region of f / fm <1 is also referred to as an isothermal region, and in this isothermal region, the Q value increases as f / fm decreases. This is because as the mechanical frequency of the vibrating arm becomes lower (the vibration of the vibrating arm becomes slower), the temperature difference in the vibrating arm as described above becomes less likely to occur. Therefore, in the limit when f / fm is brought as close as possible to 0 (zero), the isothermal quasi-static operation is performed, and the thermoelastic loss approaches 0 (zero) as much as possible. On the other hand, the region where f / fm> 1 is also referred to as an adiabatic region, and in this adiabatic region, the Q value increases as f / fm increases. This is because as the mechanical frequency of the vibrating arm increases, the temperature rise on each side surface and the switching of the temperature effect become faster, and the time for heat conduction as described above disappears. Therefore, in the limit when f / fm is increased as much as possible, the heat elastic loss becomes infinitely close to 0 (zero) due to the heat insulating operation. From this, it can be said that satisfying the relationship of f / fm> 1 means that f / fm is in the adiabatic region.

Since the constituent materials (metal materials) of the first and second driving electrodes 84 and 85 have higher thermal conductivity than the crystal which is the constituent material of the vibrating arms 5 and 6, the vibrating arm 5 has a higher thermal conductivity. 1 The heat conduction through the drive electrode 84 is positively performed, and in the vibrating arm 6, the heat conduction through the second drive electrode 85 is positively performed. If heat conduction is positively performed through the first and second drive electrodes 84 and 85, the relaxation time τ becomes short. Therefore, in the vibrating arm 5, the first drive electrode 84 is divided into a side surface 513 side and a side surface 514 side at the bottom surfaces of the grooves 52 and 53, and in the vibrating arm 6, the second drive is performed at the bottom surfaces of the grooves 62 and 63. It is preferable to prevent or suppress the above-mentioned heat conduction by dividing the electrode 85 into a side surface 613 side and a side surface 614 side. As a result, the vibration element 2 having a higher Q value can be obtained by preventing the relaxation time τ from being shortened.

Next, the relationship between the total length of the vibrating arms 5 and 6 and the length and width of the hammer heads 59 and 69 will be described. Since the vibrating arms 5 and 6 have the same configuration as each other, the vibrating arm 5 will be described as a representative below, and the description of the vibrating arm 6 will be omitted.
As shown in FIG. 1, when the total length (length in the Y-axis direction) of the vibrating arm 5 is L [μm] and the length of the hammer head 59 (length in the Y-axis direction) is H [μm]. The vibrating arm 5 preferably satisfies the relationship of 0.012 <H / L <0.3, and more preferably satisfies the relationship of 0.046 <H / L <0.223. By satisfying such a relationship, the CI value of the vibrating element 2 can be suppressed to a low value, so that the vibrating element 2 has a small vibration loss and excellent vibration characteristics.

Here, in the present embodiment, the vibrating arm 5 is a line segment connecting the base end of the vibrating arm 5 with a portion where the side surface 514 is connected to the base portion 4 and a portion where the side surface 513 is connected to the base portion 4. It is set at the center of the width (length in the X-axis direction). Further, the free end portion of the arm portion 51 has a tapered shape in which the width gradually increases toward the free end side, and the width (length in the X-axis direction) of this tapered portion is the width (X) of the arm portion 51. When the arm portion 51 has a portion that is 1.5 times or more the length in the axial direction), this portion is also included in the length H of the hammer head 59.

Further, when the width of the arm portion 51 (length in the X-axis direction) is W1 [μm] and the width of the hammer head 59 (length in the X-axis direction) is W2 [μm], the vibrating arm 5 is 1 It is preferable that the relationship of .5 ≦ W2 / W1 ≦ 10.0 is satisfied, and more preferably that the relationship of 1.6 ≦ W2 / W1 ≦ 7.0 is satisfied. By satisfying such a relationship, a wide width of the hammer head 59 can be secured. Therefore, even if the length H of the hammer head 59 is relatively short as described above (even if it is less than 30% of L), the mass effect of the hammer head 59 can be sufficiently exerted. Therefore, by satisfying the relationship of 1.5 ≦ W2 / W1 ≦ 10.0, the total length L of the vibrating arm 5 can be suppressed, and the vibrating element 2 can be miniaturized.

As described above, in the vibrating arm 5, the synergy of these two relationships is achieved by satisfying the relationship of 0.012 <H / L <0.3 and the relationship of 1.5 ≦ W2 / W1 ≦ 10.0. Due to the effect, the vibrating element 2 whose CI value is sufficiently suppressed by miniaturization can be obtained.
By setting L to 2 mm or less, preferably 1 mm or less, a small vibrating element 2 used for an oscillator mounted on a portable music device or an IC card can be obtained. Further, by setting W1 to 100 μm or less, preferably 50 μm or less, it is possible to obtain a vibrating element 2 that resonates at a low frequency used in an oscillation circuit that realizes low power consumption even in the above range of L.

Further, in the heat insulating region, when the vibrating arm extends in the Y-axis direction on the Z-cut crystal plate and flexes and vibrates in the X-axis direction, W1 is preferably 12.8 μm or more, and X on the Z-cut crystal plate. When the vibrating arm extends in the axial direction and bends and vibrates in the Y-axis direction, W1 is preferably 14.4 μm or more, and the vibrating arm extends in the Y-axis direction with the X-cut crystal plate and bends and vibrates in the Z-axis direction. In this case, W1 is preferably 15.9 μm or more. By doing so, since the adiabatic region can be surely formed, the thermoelastic loss is reduced and the Q value is improved by forming the grooves 52 and 53, and at the same time, in the region where the grooves 52 and 53 are formed. By driving, the CI value becomes low (the electric field efficiency is high and the driving area can be earned).

Further, the bank portions (main surfaces arranged with the groove 52 sandwiched along the width direction orthogonal to the longitudinal direction of the vibrating arm) 511a and the grooves of the main surface 512 located on both sides of the groove 52 of the main surface 511 in the X-axis direction. When the width (length in the X-axis direction) of the bank portions 512a located on both sides in the X-axis direction of 53 is W3 [μm], W3 is set to 6 μm or less. As a result, the equivalent series resistance R1 (CI value) can be sufficiently lowered while maintaining the Q value of the vibrating element 2 relatively high. As a result, it is possible to obtain a vibration element 2 capable of exhibiting excellent vibration characteristics with low power consumption.

Here, the grounds for setting the width W3 of the bank portions 511a and 512a to 6 μm or less will be described based on the simulation results performed by the inventors. In the following, a simulation using a vibration element 2 in which a Z-cut crystal plate is patterned and a bending vibration frequency (mechanical bending vibration frequency) f = 32.768 kHz is used as a representative, but the inventors have described it. It has been confirmed that there is almost no difference from the simulation results shown below in the range where the bending vibration frequency f is 32.768 kHz ± 1 kHz.

Further, in this simulation, a vibrating element 2 in which a Z-cut crystal plate (rotation angle 0 °) is patterned by wet etching is used. Therefore, as shown in FIG. 7, the grooves 52 and 53 have a shape in which the crystal plane of the crystal appears. Note that FIG. 7 shows a cross section corresponding to the cross section taken along line BB in FIG. Since the etching rate in the −X axis direction is lower than the etching rate in the + X axis direction, the side surface in the −X axis direction has a relatively gentle inclination, and the side surface in the + X axis direction has an inclination close to vertical.

The size of the vibrating arm 5 of the vibrating element 2 used in this simulation is that the total length L is 930 μm, the thickness T is 120 μm, the width W1 of the arm 51 is 80 μm, the width W2 of the hammer head 59 is 138 μm, and the hammer head 59. The length H of is 334 μm. In such a vibrating element 2, a simulation was performed by changing the width W3 of the bank portions 511a and 512a.
It has been confirmed by the inventors that even if the total length L, the thickness T, the width W1, the width W2, and the length H are changed, the tendency is the same as the simulation result shown below. Further, in this simulation, the vibrating element 2 in which the first and second drive electrodes 84 and 85 are not formed is used.

In FIG. 8, the widths W3 and Q of the bank portions 511a and 512a when the maximum depths t of the grooves 52 and 53 are 0.208T, 0.292T, 0.375T, 0.458T and 0.483T, respectively. It is a graph which shows the relationship with the value (Q value after F conversion), and FIG. 9 shows the maximum depth t of grooves 52 and 53 set to 0.208T, 0.292T, 0.375T, 0.458T and 0, respectively. It is a graph which shows the relationship between the width W3 of a bank portion 511a, 512a and the reciprocal of R1 (1 / R1) when it is set to .483T.

The graphs shown in FIGS. 8 and 9 are created as follows. First, the Q value is obtained by the finite element method, considering only the thermoelastic loss. Since the Q value has frequency dependence, the obtained Q value is converted into the Q value at 32.768 kHz (Q value after F conversion). The graph shown in FIG. 8 is created by plotting the Q value after F conversion with the vertical axis and W3 as the horizontal axis. Further, R1 is calculated based on the Q value after F conversion. Since R1 also has frequency dependence, the obtained R1 was converted to R1 at 32.768 kHz, and the reciprocal was plotted on the vertical axis and W3 on the horizontal axis. It is a graph shown in. The larger the Q value, the higher the vibration characteristic of the vibrating element 2, and the smaller the R1 (the larger 1 / R1), the lower the power consumption of the vibrating element 2.

The conversion of the Q value to the Q value after F conversion can be calculated as follows using the above formula (1) and the following formula (3).
Q = {ρCp / (Cα ² H)} × [{1+ (f / fm0) ² } / (f / fm0)]
(3) However, in equation (3), ρ is the mass density of the vibrating arm 5, Cp is the heat capacity of the vibrating arm 5, C is the elastic stiffness constant of expansion and contraction in the length direction of the vibrating arm 5, and α is the vibrating arm. The thermal expansion rate in the length direction of 5, H is the absolute temperature, and f is the natural frequency. Note that a is the width (effective width) that the vibrating arm 5 is considered to have a flat plate structure (flat plate shape), but even if this value of a is used, it is converted to the Q value after F conversion. be able to.

First, the natural frequency of the vibrating arm 5 used in the simulation is F1, the obtained Q value is Q1, and the equations (1) and (3) are used so that f = F1 and Q = Q1. Find the value. Next, the obtained a is used, f = 32.768 kHz, and the Q value is calculated from the equation (3). The Q value obtained in this way becomes the Q value after F conversion.
As shown in FIG. 8, the Q value takes the maximum value when the width W3 of the bank portions 511a and 512a is 7 μm regardless of the depth of the grooves 52 and 53. On the other hand, as shown in FIG. 9, R1 tends to become smaller as the width W3 of the bank portions 511a and 512a becomes smaller. The vibrating element is usually designed so that the Q value is as large as possible, that is, the width W3 of the bank portions 511a and 512a is about 7 μm. However, with this, the power consumption of the vibrating element 2 cannot be sufficiently reduced.

Therefore, in the present invention, the design value of the width W3 of the bank portions 511a and 512a is not intentionally set to the value normally adopted (7 μm at which the Q value is the maximum), and even if the Q value is sacrificed to some extent, R1 becomes more favorable. It was decided to preferentially adopt a smaller value (6 μm or less). As a result, the equivalent series resistance R1 (CI value) can be sufficiently lowered while maintaining the Q value of the vibrating element 2 relatively high. As a result, it is possible to obtain a vibration element 2 capable of exhibiting excellent vibration characteristics with low power consumption.

The width W3 of the bank portions 511a and 512a may be 6 μm or less, preferably 0.1 μm or more and 6 μm or less, more preferably 0.5 μm or more and 4 μm or less, and 1 μm or more and 3 μm or less. Is even more preferable. By setting the width W3 to such a range, the R1 (CI value) of the vibrating element 2 can be made smaller, and the vibrating element 2 can be driven with lower power consumption. It is difficult to form the bank portions 511a and 512a having a width W3 smaller than the above lower limit value, or a processing technique having extremely high accuracy is required, which increases the cost.

Further, the thickness T of the vibrating arm 5 (arm 51) and the maximum depth t of the grooves 52 and 53 satisfy the relationship of 0.458T ≦ t ≦ 0.483T, and the bank portions 511a and 512a are satisfied. Width W3 and η represented by 2t / T have a relationship of −36.000η + 39.020≤W3 [μm] ≤26.000η-15.320 (however, 0.916≤η≤0.966). It is preferable to be satisfied. As a result, it is possible to obtain a vibration element 2 that exhibits more excellent vibration characteristics.

In particular, the greater the depth of the grooves 52, 53, that is, η, the more preferably, specifically 0.6 or more, more preferably 0.75 or more, and 0.9 or more. Is even more preferable. As a result, the formed areas of the first and second driving electrodes 84 and 85 can be increased, so that the R1 (CI value) of the vibrating element 2 can be made smaller, and the vibration driven with lower power consumption can be obtained. The element 2 can be obtained.

Further, since η satisfies the relationship of 2t / T, when η is constant, t can be increased as the thickness T of the vibrating arm 5 (crystal substrate 3) increases. As a result, the formed areas of the first and second driving electrodes 84 and 85 can be made larger, so that R1 of the vibrating element 2 can be made even smaller. Specifically, the thickness T of the vibrating arm 5 (crystal substrate 3) is preferably 50 μm or more, more preferably 110 μm or more, and further preferably 160 μm or more. The upper limit of the thickness T of the vibrating arm 5 is not particularly limited, but is preferably 300 μm or less. When the thickness T of the vibrating arm 5 exceeds the upper limit value, the shape asymmetry of the vibrating element 2 tends to increase, although it depends on the processing conditions (wet etching conditions) of the crystal substrate 3.

Between the pair of vibrating arms 5 and 6 (arms 51 and 61) as described above, a support arm 71 extending from the base 4 (main body 41) along the center line C1 (Y-axis direction) is provided. It is provided. The support arm 71 has a substantially rectangular shape in XY plan view, and the vibrating element 2 is fixed to the package 9 by the support arm 71 via the conductive adhesive 11 as shown in FIGS. 1 and 2. However, the present invention is not particularly limited, and the package 9 may be fixed to the package 9 via a metal such as Au. With such a configuration, vibration leakage of the vibrating element 2 can be reduced more effectively.

Further, the support arm 71 has a constricted portion 711 having a small length (width) along the X-axis direction near the boundary portion with the base portion 4. As a result, from the resonance frequency of the main mode in which the vibrating arms 5 and 6 bend and vibrate so as to separate and approach each other, the resonance frequency of the X in-phase mode in which the vibrating arms 5 and 6 bend and vibrate in the same direction in the XY plane is changed. Can be separated. As a result, when the vibrating element 2 is flexed and vibrated in the main mode, so-called coupled vibration, in which the vibration form generated in the X common-phase mode overlaps with the main mode, is less likely to occur, and vibration leakage can be reduced.

Such a vibrating element 2 can be obtained by processing a crystal substrate by, for example, a wet etching method such as alkaline wet etching, a laser beam etching, or a dry etching method such as reactive gas etching. It is preferably obtained by processing by a wet etching method. According to the wet etching method, the crystal substrate can be processed with high accuracy with a simple device.

(package)
The package 9 has a box-shaped base 91 having a recess 911 that opens to the upper surface, and a plate-shaped lid 92 that is joined to the base 91 so as to close the opening of the recess 911. Such a package 9 has a storage space formed by closing the recess 911 with a lid 92, and the vibration element 2 is airtightly stored in this storage space. The vibrating element 2 is fixed to the bottom surface of the recess 911 by the support arm 71 via, for example, a conductive adhesive 11 in which a conductive filler is mixed with an epoxy-based or acrylic-based resin.
The storage space may be in a reduced pressure (preferably vacuum) state, or may be filled with an inert gas such as nitrogen, helium, or argon. As a result, the vibration characteristics of the vibrating element 2 are improved.

The constituent material of the base 91 is not particularly limited, but various ceramics such as aluminum oxide can be used. Further, the constituent material of the lid 92 is not particularly limited, but a member having a linear expansion coefficient similar to that of the constituent material of the base 91 is preferable. For example, when the constituent material of the base 91 is the above-mentioned ceramics, it is preferable to use an alloy such as Kovar. The joining of the base 91 and the lid 92 is not particularly limited, and may be joined by, for example, an adhesive or seam welding.

Further, connection terminals 951 and 961 are formed on the bottom surface of the recess 911 of the base 91. Although not shown, the first drive electrode 84 of the vibrating element 2 is pulled out halfway in the Y-axis direction of the support arm 71, and the conductive adhesive 11 is electrically connected to the connection terminal 951 at this portion. Has been done. Similarly, although not shown, the second drive electrode 85 of the vibrating element 2 is pulled out halfway in the Y-axis direction of the support arm 71, and at that portion, the connection terminal 961 is interposed via the conductive adhesive 11. Is electrically connected to.
Further, the connection terminal 951 is electrically connected to an external terminal 953 formed on the bottom surface of the base 91 via a through electrode 952 penetrating the base 91, and the connection terminal 961 is a through electrode penetrating the base 91. It is electrically connected to an external terminal 963 formed on the bottom surface of the base 91 via 962.

The configurations of the connection terminals 951 and 961, the through electrodes 952 and 962, and the external terminals 953 and 963 are not particularly limited as long as they have conductivity, but for example, Cr (chromium), W (tungsten), etc. It can be composed of a metal coating in which each coating such as Ni (nickel), Au (gold), Ag (silver), Cu (copper) is laminated on the metallized layer (underlayer) of.

<Second Embodiment>
Next, a second embodiment of the oscillator of the present invention will be described.
FIG. 10 is a plan view of the vibrating element included in the vibrator according to the second embodiment of the present invention.
Hereinafter, the oscillator of the second embodiment will be described mainly on the differences from the first embodiment described above, and the same matters will be omitted.
The oscillator of the second embodiment is the same as that of the first embodiment described above, except that the configuration of the vibrating element is different. The same reference numerals are given to the same configurations as those of the first embodiment described above.

As shown in FIG. 10, the base portion 4A of the vibrating element 2A includes a main body portion 41, a narrowed width portion 42 provided on the base end (second end portion) side of the main body portion 41, and vibrating arms 5 and 6. In between, it has a narrowed width portion 43 provided on the tip end (first end portion) side of the main body portion 41. Such a vibrating element 2A is fixed to the package 9 at the main body 41 via the conductive adhesives 11 and 11. Therefore, the support arm 71 is omitted.

The width of the narrowed portion 43 (length along the X-axis direction) gradually decreases as it moves away from the center of the base 4 (main body 41) along the center line C1 between the vibrating arms 5 and 6. Its contour (edge) is arched (arc-shaped). Such a narrowing portion 43 has the same function as the narrowing portion 42. Further, in the present embodiment, the conductive adhesives 11 and 11 are arranged along the center line C1, but may be arranged along a direction (X-axis direction) orthogonal to the center line C1.

Even with such a second embodiment, the same effect as that of the first embodiment described above can be exhibited. In particular, according to the second embodiment, since the support arm 71 can be omitted, the length (width) of the vibrating element 2A along the X-axis direction can be reduced. The base portion 4 may not have the narrowing portion 42 and may have only the narrowing portion 43, or may not have the narrowing portion 43 and may have only the narrowing portion 42. ..

<Third Embodiment>
Next, a third embodiment of the oscillator of the present invention will be described.
FIG. 11 is a plan view of the oscillator according to the third embodiment of the present invention, and FIG. 12 is a sectional view taken along line CC in FIG.
Hereinafter, the oscillator of the third embodiment will be described mainly on the differences from the first embodiment described above, and the same matters will be omitted.
The oscillator of the third embodiment is the same as that of the first embodiment described above, except that the configuration of the support portion and the configuration of the package are different. The same reference numerals are given to the same configurations as those of the first embodiment described above.

As shown in FIG. 11, the support portion of the vibrating element 2B includes a frame body 72 having a substantially square outer shape that surrounds the base portion 4, the vibrating arms 5, 6 and the support arm 71B, and the support arm 72 is provided with the frame body 72. The tip end portion (the end portion on the side opposite to the base portion 4) of 71B is connected. The frame body 72 is a portion joined to the package 9B.
As shown in FIG. 12, the package 9B has a box-shaped base 91B having a recess 911B open to the upper surface and a box-shaped lid 92B having a recess 921B to open to the lower surface, and has an outer peripheral portion of the base 91B and a box-shaped lid 92B. The vibrating element 2B is fixed to the package 9B by sandwiching and joining the frame body 72 to the outer peripheral portion of the lid 92B. Further, a connection terminal 961 (951) provided on the bottom surface of the recess 911B of the base 91B and a predetermined portion of the vibrating element 2B are connected by, for example, a wire 12 made of gold or the like.
Even with such a third embodiment, the same effect as that of the first embodiment described above can be exhibited. In particular, according to the third embodiment, since the vibrating element 2B is fixed to the package 9B via the frame body 72, this fixing can be performed with high accuracy. Therefore, the size of the vibrating element 2B can be increased, and as a result, its R1 can be made smaller.

<Fourth Embodiment>
Next, a fourth embodiment of the oscillator of the present invention will be described.
FIG. 13 is a plan view of the vibrating element included in the vibrator according to the fourth embodiment of the present invention.
Hereinafter, the oscillator of the fourth embodiment will be described mainly on the differences from the above-mentioned first to third embodiments, and the same matters will be omitted.
The oscillator of the fourth embodiment is the same as that of the third embodiment described above, except that the configuration of the support portion is different. The same reference numerals are given to the same configurations as those in the third embodiment described above.

As shown in FIG. 13, the support portion of the vibrating element 2C is a support extending along the center line C1 to the base end (opposite to the pair of vibrating arms 5 and 6) side of the base portion 4C instead of the support arm 71B. An arm 73 is provided. The support arm 73 is connected to the frame body 72. The base 4C has the same configuration as the base 4A of the second embodiment.
Even with such a fourth embodiment, the same effect as that of the first embodiment described above can be exhibited. In particular, according to the fourth embodiment, since the vibrating element 2C is fixed to the package 9 via the frame body 72, this fixing can be performed with high accuracy. Therefore, the size of the vibrating element 2C can be increased, and as a result, its R1 can be made smaller. Further, according to the fourth embodiment, since the support arm 71B can be omitted, the length (width) of the vibrating element 2C along the X-axis direction can be reduced.
The support arm 73 may be omitted and the base 4C may be directly connected to the frame body 72, or the frame body 72 may be omitted and the support arm 73 may use the conductive adhesive 11 to vibrate the vibrating element. 2C may be fixed to the package 9.

2. 2. Oscillator Next, an oscillator to which the vibrating element of the present invention is applied (oscillator of the present invention) will be described.
FIG. 14 is a cross-sectional view showing a preferred embodiment of the oscillator of the present invention.
The oscillator 10 shown in FIG. 14 has an oscillator 1 and an IC chip 8 for driving the vibrating element 2. Hereinafter, the oscillator 10 will be mainly described with respect to the differences from the above-mentioned oscillator, and the same matters will be omitted.

As shown in FIG. 14, the package 9 has a box-shaped base 91 having a recess 911 and a plate-shaped lid 92 that closes the opening of the recess 911. Further, the recesses 911 of the base 91 include a first recess 911a that opens to the upper surface of the base 91, a second recess 911b that opens to the bottom surface of the first recess 911a, and a third recess 911c that opens to the bottom surface of the second recess 911b. And have.

Connection terminals 95 and 96 are formed on the bottom surface of the first recess 911a. Further, an IC chip 8 is arranged on the bottom surface of the third recess 911c. The IC chip 8 has an oscillation circuit for controlling the drive of the vibrating element 2. When the vibrating element 2 is driven by the IC chip 8, a signal having a predetermined frequency can be extracted.
Further, a plurality of internal terminals 93 electrically connected to the IC chip 8 via a wire are formed on the bottom surface of the second recess 911b. These plurality of internal terminals 93 are electrically connected to the external terminals 94 formed on the bottom surface of the package 9 via vias (not shown) formed on the base 91, and via vias and wires (not shown). A terminal electrically connected to the connection terminal 95 and a terminal electrically connected to the connection terminal 96 via a via or a wire (not shown) are included.
In the configuration of FIG. 14, the configuration in which the IC chip 8 is arranged in the storage space has been described, but the arrangement of the IC chip 8 is not particularly limited, and for example, the outside of the package 9 (bottom surface of the base 91). It may be arranged in.

3. 3. Electronic device Next, an electronic device to which the vibration element of the present invention is applied (the electronic device of the present invention) will be described.
FIG. 15 is a perspective view showing the configuration of a mobile (or notebook) personal computer to which an electronic device including the vibration element of the present invention is applied. In this figure, the personal computer 1100 is composed of a main body 1104 having a keyboard 1102 and a display unit 1106 having a display 2000, and the display unit 1106 rotates with respect to the main body 1104 via a hinge structure. It is movably supported. Such a personal computer 1100 has a built-in vibrating element 2 (2A to 2C) that functions as a filter, a resonator, a reference clock, and the like.

FIG. 16 is a perspective view showing the configuration of a mobile phone (including PHS) to which an electronic device including the vibration element of the present invention is applied. In this figure, the mobile phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and a display unit 2000 is arranged between the operation button 1202 and the earpiece 1204. Such a mobile phone 1200 has a built-in vibrating element 2 (2A to 2C) that functions as a filter, a resonator, and the like.

FIG. 17 is a perspective view showing a configuration of a digital still camera to which an electronic device including the vibration element of the present invention is applied. Note that this figure also briefly shows the connection with an external device. Here, while a normal camera exposes a silver halide photographic film by the light image of the subject, the digital still camera 1300 photoelectrically converts the light image of the subject by an image sensor such as a CCD (Charge Coupled Device). Generates an image pickup signal (image signal).

A display unit 2000 is provided on the back surface of the case (body) 1302 of the digital still camera 1300, and the display unit 2000 displays the subject as an electronic image based on the imaging signal obtained by the CCD. Functions as a finder. Further, on the front side (back side in the drawing) of the case 1302, a light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided.

When the photographer confirms the subject image displayed on the display unit 2000 and presses the shutter button 1306, the image pickup signal of the CCD at that time is transferred and stored in the memory 1308. Further, in the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. Then, as shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312, and a personal computer 1440 is connected to the input / output terminal 1314 for data communication, respectively, as needed. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation. Such a digital still camera 1300 has a built-in vibrating element 2 (2A to 2C) that functions as a filter, a resonator, and the like.

In addition to the personal computer (mobile personal computer) shown in FIG. 15, the mobile phone shown in FIG. 16, and the digital still camera shown in FIG. 17, the electronic device provided with the vibrating element of the present invention includes, for example, an inkjet ejection device (for example,). Inkjet printer), laptop personal computer, TV, video camera, video tape recorder, car navigation device, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game equipment, word processor, workstation, TV Telephone, security TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish finder, various measuring devices, instruments It can be applied to a class (for example, a vehicle, an aircraft, a ship's instrument), a flight simulator, and the like.

4. Moving body Next, a moving body to which the vibrating element of the present invention is applied (moving body of the present invention) will be described.
FIG. 18 is a perspective view schematically showing an automobile as an example of the moving body of the present invention. The vibration element 2 is mounted on the automobile 1500. Vibrating elements 2 (2A-2C) include keyless entry, immobilizer, car navigation system, car air conditioner, anti-lock brake system (ABS), airbag, tire pressure monitoring system (TPMS), engine. It can be widely applied to electronic control units (ECUs) such as controls, battery monitors for hybrid vehicles and electric vehicles, and body posture control systems.

The vibrating element, oscillator, oscillator, electronic device, and mobile body of the present invention have been described above based on the illustrated embodiments, but the present invention is not limited thereto, and the configurations of each part are the same. It can be replaced with any configuration having a function. Further, any other constituents may be added to the present invention. Moreover, each embodiment may be combined appropriately.

1, 1B ... oscillator 10 ... oscillator 11 ... conductive adhesive 12 ... wire 2, 2A, 2B, 2C ... vibrating element 3 ... crystal substrate 4, 4A, 4C ... base 41 ... main body 42, 43 ... narrowed portion 5 ... Vibrating arm 51 ... Arm 511, 512 ... Main surface 511a, 512a ... Bank 513, 514 ... Side 52, 53 ... Groove 59 ... Hammer head 6 ... Vibrating arm 61 ... Arm 611, 612 ... Main surface 613, 614 ... Side surface 62, 63 ... Groove 69 ... Hammer head 71, 71B, 73 ... Support arm 711 ... Constriction 72 ... Frame 8 ... IC chip 84, 85 ... Drive electrode 9 ... Package 91, 91B ... Base 911, 911B , 921B ... Concave 911a ... 1st recess 911b ... 2nd recess 911c ... 3rd recess 92, 92B ... Lid 93 ... Internal terminal 94 ... External terminal 95, 96 ... Connection terminal 951, 961 ... Connection terminal 952, 962 ... Through electrode 953, 963 ... External terminal 1100 ... Personal computer 1102 ... Keyboard 1104 ... Main unit 1106 ... Display unit 1200 ... Mobile phone 1202 ... Operation button 1202 ... Earpiece 1206 ... Mouthpiece 1300 ... Digital still camera 1302 ... Case 1304 ... Light receiving unit 1306 ... Shutter button 1308 ... Memory 1312 ... Video signal output terminal 1314 ... Input / output terminal 1430 ... TV monitor 1440 ... Personal computer 1500 ... Automobile 2000 ... Display L ... Overall length H ... Hammer head length W1, W2, W3 ... Width t ... Depth T ... Thickness C1 ... Center line

Claims (8)

A first end and a base including a second end opposite to the first end in plan view.
A pair of vibrating arms extending along a first direction from the first end side of the base and lining up along a second direction orthogonal to the first direction.
A frame body surrounding the base and the vibrating arm in a plan view,
A support arm that connects the base and the frame and has a first width that is smaller than the distance between the pair of vibrating arms.
Including
The base includes a second width that is greater than or equal to the length along the second direction of the portion to which the pair of vibrating arms at the first end are connected.
The base, between the supporting arms, contraction of the length along the second direction is smaller continuously until the first width from said second width as it approaches the said support arm Including the width part
The vibrating arm
With the arm
A wide portion of the arm that is located on the side opposite to the base side and has a larger length in the second direction than the arm.
Including
One and the other of the pair of vibrating arms, respectively.
A pair of main surfaces that are in a front-to-back relationship along the first direction and the second direction.
A pair of side surfaces connecting the pair of main surfaces and
A bottomed groove portion provided on each of the main surfaces along the first direction and having a depth along the direction of thickness orthogonal to each of the main surfaces.
Including
A portion that is connected to one of the pair of side surfaces and is aligned with the groove portion along the second direction on the main surface of the vibrating arm in a plan view is defined as a first bank portion.
The portion which is connected to the other of the pair of side surfaces and is aligned with the groove portion along the second direction on the main surface of the vibrating arm in a plan view is defined as a second bank portion.
The length of the vibrating arm along the first direction is 1000 μm or less.
The length of the arm portion along the second direction is 12.8 μm or more and 50 μm or less.
The width of the first bank portion and the second bank portion is 6 μm or less.
When the length of the arm portion along the second direction is W1 and the length of the wide portion along the second direction is W2.
1.6 ≤ W2 / W1 ≤ 7.0
A vibrating element characterized by satisfying the above relationship. In claim 1,
When the length of the vibrating arm along the first direction is L and the length of the wide portion along the first direction is H.
0.012 <H / L <0.3
A vibrating element characterized by satisfying the above relationship. In claim 1 or 2,
A vibrating element characterized in that the widths of the first bank portion and the second bank portion are 1 μm or more and 3 μm or less. In any one of claims 1 to 3,
A vibrating element having a vibrating arm having a thickness of 50 μm or more and 300 μm or less. The vibrating element according to any one of claims 1 to 4,
A pair of package bases holding the frame and
An oscillator characterized by including. The vibrating element according to any one of claims 1 to 4,
Oscillator circuit and
An oscillator characterized by including. An electronic device including the vibrating element according to any one of claims 1 to 4. A moving body including the vibrating element according to any one of claims 1 to 4.

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