JP6005442B2 - Crystal oscillator - Google Patents

Description

  The present invention relates to a crystal resonator element used for a reference signal source or a clock signal source, for example. Hereinafter, a tuning fork-type bending quartz crystal vibrating element (hereinafter abbreviated as “vibrating element”) will be described as an example of a quartz crystal vibrating element.

  FIG. 7 is a plan view showing a vibration element according to Related Technique 1. FIG. Hereinafter, description will be given based on this drawing.

  The vibration element 100 according to the related technique 1 includes a base portion 11 and a pair of vibrating arm portions 12 extending in parallel from the base portion 11. The vibrating arm portion 12 includes a first vibrating arm portion 12a and a second vibrating arm portion 12b. Groove portions 13a and 13b are formed in the first vibrating arm portion 12a and the second vibrating arm portion 12b, respectively.

  Excitation electrodes 21a and 21b are formed on the vibrating arm portion 12 and the groove portions 13a and 13b. Two electrode pads 22 a and 22 b are formed on the base 11. The electrode pads 22a and 22b are arranged in a separated state so as to be insulated from each other. The excitation electrode 21a formed on the side surface of the first vibrating arm portion 12a and the groove portion 13b of the second vibrating arm portion 12b and the electrode pad 22a formed on the base portion 11 are wired and connected so as to have the same polarity. ing. The excitation electrode 21b formed on the side surface of the second vibrating arm portion 12b and the groove portion 13a of the first vibrating arm portion 12a and the electrode pad 22b formed on the base portion 11 are wired and connected so as to have the same polarity. ing.

  The electrode pads 22a and 22b are electrically connected simultaneously with the electrode pads (not shown) on the package side via the conductive adhesive 31. When an alternating voltage is applied to the electrode pads 22a and 22b, the vibrating arm portion 12 expands and contracts due to the generated electric field, whereby a bending vibration having a predetermined resonance frequency occurs in the vibrating element 100. In addition, although the conductive adhesive 31 in FIG. 7 is shown only on the electrode pad 22a side, it is similarly applied to the electrode pad 22b side.

  The vibration element 100 is used as a synchronization signal source in an electronic device such as a mobile phone. With recent miniaturization of electronic equipment, the vibration element 100 used therein is also required to be miniaturized. In reducing the size of the vibration element 100, it is necessary to shorten the lengths of the vibrating arm portion 12 and the base portion 11. When the base portion 11 is shortened, vibration from the vibrating arm portion 12 is not sufficiently absorbed in the base portion 11 and leaks to an external package or the like through a fixed portion of the base portion 11 (hereinafter referred to as “vibration leakage”). .) Occurs. This vibration leakage is a loss of vibration energy, and causes deterioration (increase) in CI (Crystal Impedance), which is an important characteristic value for the vibration element 100.

  As a structure for suppressing this vibration leakage, Patent Documents 1 and 2 disclose a technique in which cut portions 114 a and 114 b are provided in the base 11. By inserting the notches 114a and 114b into the base 11, the vibration arm 12 side of the base 11 where the vibration displacement is relatively large, and the electrode pads 22a of the base 11 fixed to the package with the conductive adhesive 31, Since the 22b side can be separated, vibration leakage can be suppressed. In addition, the shape of the notches 114a and 114b is a rectangular shape extending perpendicularly to the extending direction of the vibrating arm portion 12.

  FIG. 8 is a plan view showing a resonator element according to Related Technique 2. Hereinafter, description will be given based on this drawing.

  In the vibration element 200 of the related art 2, in order to further reduce the vibration energy leaking to the fixed region, the cut depths of the cut portions 214a and 214b are further increased in the width direction of the base portion 11. Here, the cut depths of the cut portions 214a and 214b are distances from the base ends of the cut portions 214a and 214b to the tips of the cut portions 214a and 214b (that is, the base center side end surface 202). Other configurations of the vibration element 200 of the related technology 2 are the same as those of the related technology 1.

JP 59-183520 A JP 2002-261575 A JP 2011-151567 A

  Hereinafter, problems to be solved by the present invention will be described with reference to FIGS.

  In Related Art 1, when the base 11 is shortened for the size reduction of the vibration element 100, the distance between the vibration arm portion 12 side of the base 11 having a large vibration displacement and the electrode pads 22a and 22b side of the base 11 which is a fixed region is increased. Shorter. Similarly, the distance between the cut portions 114a and 114b and the conductive adhesive 31 in the electrode pads 22a and 22b is also shortened. On the other hand, in order to stably fix the vibration element 100, the adhesion region cannot be narrowed. Therefore, the application area of the conductive adhesive 31 needs to be approximately the same as the application area before the vibration element 100 is downsized.

  As a result, along with the downsizing of the vibration element 100, the portions where the vibration displacement is relatively large in the cut portions 114a and 114b, particularly the vibration arm side end surface 101 and the base center side end surface 102 of the cut portions 114a and 114b. Then, the conductive adhesive 31 protrudes. The conductive adhesive 31 shown in FIG. 7 may not only reach the base-center-side end surface 102 in the cut portion 114a, but may crawl up to the vibrating arm-side end surface 101 extending from the cut portion 114a by the action of surface tension. There is also. Then, since the conductive adhesive 31 inhibits vibration on the vibration arm portion side end surface 101 and the base center side end surface 102, the CI increases and the incisions 114a and 114b are not formed. This problem also applies to the vibration element 200 of the related technique 2.

  Further, in the vibration element 200 of the related technique 2 shown in FIG. 8, the conductive adhesive 31 is unlikely to reach the base-center side end face 202 of the cut portion 214a, so that the influence of the conductive adhesive 31 can be suppressed to some extent. However, a region with an extremely narrow width is formed in the base-center-side end face 202 as the cut depths of the cut portions 214a and 214b are further increased in the width direction of the base portion 11. For this reason, the strength for holding the vibrating arm portion 12 is reduced, so that the resistance of the vibrating element 200 is deteriorated against an impact such as dropping.

  Therefore, an object of the present invention is to increase the depth of cut of the cut portion when the cut portion is formed in the base portion, while avoiding unnecessary contact between the cut portion and the adhesive, thereby achieving low CI. It is to provide a vibration element to be obtained.

The vibration element according to the present invention is
A base, a vibration portion extending from the base, a cut portion formed in the base, and an adhesive for fixing the base to an element mounting member;
In a vibration element comprising
The base portion has a quadrangular shape having a first side provided with the vibrating portion, a second side facing the first side, and a third side and a fourth side formed with the cut portion and facing each other. Yes, fixed to the element mounting member via the adhesive applied in a circular shape around each of the two apexes sandwiching the second side,
The cut portion is Ri shape der away from the vibrating unit as one proceeds inwardly of the base portion, a first surface which is not in contact with the adhesive be in the first window side, said there to the second window side A second surface in contact with the adhesive,
The first surface has an arc shape along the periphery of the adhesive.
It is characterized by that.

  According to the present invention, by adopting the incision portion that is shaped to move away from the vibration portion as it goes inside the base portion, the incision depth of the incision portion can be increased while maintaining the distance between the incision portion and the adhesive application region. Further, unnecessary contact between the cut portion and the adhesive can be avoided, and a low CI can be achieved by the cut portion.

FIG. 3 is a plan view showing the resonator element according to the first embodiment. It is the II-II line longitudinal cross-sectional view in FIG. It is a schematic sectional drawing which shows the state which mounted the vibration element of FIG. 1 on the element mounting member. 6 is a plan view showing a vibration element according to Embodiment 2. FIG. FIG. 6 is a plan view illustrating a vibration element according to a third embodiment. FIG. 6 is a plan view illustrating a vibration element according to a fourth embodiment. FIG. 12 is a plan view showing a vibration element of Related Art 1. FIG. 10 is a plan view showing a vibration element of Related Art 2.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “embodiments”) will be described with reference to the accompanying drawings. In the present specification and drawings, the same reference numerals are used for substantially the same components. The shapes depicted in the drawings are drawn so as to be easily understood by those skilled in the art, and thus do not necessarily match the actual dimensions and ratios.

  FIG. 1 is a plan view of the resonator element according to the first embodiment. 2 is a longitudinal sectional view taken along line II-II in FIG. FIG. 3 is a schematic cross-sectional view illustrating a state where the vibration element of FIG. 1 is mounted on an element mounting member. Hereinafter, description will be given with reference to FIGS.

  The vibration element 10 according to the first exemplary embodiment fixes the base 11, the vibrating arm portion 12 extending from the base 11, the cut portions 14 a and 14 b formed in the base 11, and the base 11 to the element mounting member 32. And a conductive adhesive 31. The notches 14 a and 14 b have a shape that moves away from the vibrating arm 12 as it moves inward of the base 11.

  The base portion 11 includes a first side 111 provided with the vibrating arm portion 12, a second side 112 facing the first side 111, cut portions 14a and 14b, and a third side 113 and a second side facing each other. A quadrangular shape having four sides 114. The base 11 is fixed to the element mounting member 32 via the conductive adhesive 31 applied to the two apexes 112a and 112b sandwiching the second side 112. In addition, although the conductive adhesive 31 in FIG. 1 is shown only on the electrode pad 22a side, it is similarly applied to the electrode pad 22b side.

  The cut portion 14 a has a first surface 141 a that is on the first side 111 side and does not contact the conductive adhesive 31, and a second surface 142 a that is on the second side 112 side and contacts the conductive adhesive 31. The cut portion 14 b has a first surface 141 b that is on the first side 111 side and does not contact the conductive adhesive 31, and a second surface 142 b that is on the second side 112 side and contacts the conductive adhesive 31. The conductive adhesive 31 is circularly applied to the two vertices 112a and 112b. The first surfaces 141 a and 141 b have an arc shape along the periphery of the conductive adhesive 31. The second surfaces 142 a and 142 b are linear along the direction perpendicular to the extending direction of the vibrating arm portion 12.

  The shape of the first surfaces 141a and 141b is not limited to the arc shape, but any shape such as an elliptical arc shape, a curved shape, a straight line shape, a broken line shape, or the like that moves away from the vibrating arm portion 12 as it goes inside the base portion 11 can be used. It may be anything. Further, the vibrating arm portion 12 and the conductive adhesive 31 are examples of “vibrating portion” and “adhesive” described in the claims, respectively.

  Next, the configuration of the vibration element 10 will be described in more detail.

  As shown in FIGS. 1 and 2, the resonator element 10 includes a crystal vibrating piece 15, excitation electrodes 21a and 21b, electrode pads 22a and 22b, and frequency adjusting metal films 23a and 23b provided on the crystal vibrating piece 15. From, it is mainly composed.

  The quartz crystal vibrating piece 15 has a tuning fork shape, and is roughly configured by a base portion 11 and a pair of vibrating arm portions 12 extending from the base portion 11. The vibrating arm portion 12 is provided with excitation electrodes 21a and 21b having the same polarity on opposite surfaces across the quartz.

  The base 11 is a flat plate having a substantially rectangular shape in plan view. The vibrating arm portion 12 includes a first vibrating arm portion 12a and a second vibrating arm portion 12b. The first vibrating arm portion 12 a and the second vibrating arm portion 12 b extend from the first side 111 of the base portion 11 in the same direction. The crystal vibrating piece 15 has a tuning fork shape in which the base portion 11 and the vibrating arm portion 12 are integrated, and is manufactured by, for example, a film forming technique, a photolithography technique, or a chemical etching technique.

  Groove portions 13a and 13b are provided in the length direction of the first vibrating arm portion 12a and the second vibrating arm portion 12b, respectively. The groove portions 13a and 13b are, for example, two on the front and back surfaces of the first vibrating arm portion 12a and two on the front and back surfaces of the second vibrating arm portion 12b. A predetermined length is provided parallel to the length direction of the vibrating arm portion 12 toward the tip. The groove portions 13a and 13b may be provided one on each of the front and back surfaces of the first vibrating arm portion 12a and one on the front and back surfaces of the second vibrating arm portion 12b. You may provide only in either.

  The excitation electrode 21a is provided on both side surfaces of the first vibrating arm portion 12a and on the front and back surfaces of the second vibrating arm portion 12b. The excitation electrode 21b is provided on both side surfaces of the second vibrating arm portion 12b and on the front and back surfaces of the first vibrating arm portion 12a.

  The base 11 is provided with electrode pads 22a and 22b. In the base 11 and the vibrating arm 12, the excitation electrode 21a, the electrode pad 22a, and the frequency adjusting metal film 23a are electrically connected to each other, and the excitation electrode 21b, the electrode pad 22b, and the frequency adjusting metal film 23b are also electrically connected to each other. Conducted.

  These excitation electrodes 21a and 21b, electrode pads 22a and 22b, and frequency adjusting metal films 23a and 23b are formed by, for example, a film formation technique, a photolithography technique, and an etching technique. For example, a Pd or Au layer is provided on a Ti layer. It has a laminated structure.

  As shown in FIG. 3, the vibration element 10 is fixed and electrically connected to the electrode pad 33 on the element mounting member 32 side via the conductive adhesive 31 (and the electrode pads 22 a and 22 b). .

  When the tuning fork type crystal vibrating piece 15 is vibrated, an alternating voltage is applied to the electrode pads 22a and 22b. When an electrical state after application is captured instantaneously, the excitation electrodes 21b provided on the front and back surfaces of the first vibrating arm portion 12a have a positive potential, and the excitation electrodes provided on both side surfaces of the first vibrating arm portion 12a. 21a becomes a negative potential, and an electric field is generated from positive to negative. At this time, the excitation electrodes 21a provided on the front and back surfaces of the second vibrating arm portion 12b have a negative potential, the excitation electrodes 21b provided on both side surfaces of the second vibrating arm portion 12b have a positive potential, and the first vibrating arm portion. The polarity is opposite to that generated in 12a, and an electric field is generated from plus to minus. The electric field generated by the alternating voltage causes an expansion / contraction phenomenon in the first vibrating arm portion 12a and the second vibrating arm portion 12b, and a bending vibration mode having a resonance frequency set in the vibrating arm portion 12 is obtained.

  Next, the operation and effect of the vibration element 10 will be described.

  Since the notches 14a and 14b are symmetrical to each other, that is, both have the same shape, the notches 14a will be described below. Since the cut portion 14a has a shape that moves away from the vibrating arm portion 12 as it goes inward of the base portion 11, it keeps a distance from the conductive adhesive 31 applied in the vicinity of the apex 112a of the base portion 11 and moves toward the inside of the base portion 11. Will extend. Therefore, it is possible to avoid unnecessary contact between the cut portion 14a and the application region of the conductive adhesive 31 while securing the cut depth of the cut portion 14a to suppress vibration leakage, and therefore, the cut portion 14a according to the first embodiment is provided. By adopting, low CI can be achieved.

  Here, the “cut depth” refers to the shape of the cut portion 14 a from the base end (that is, the third side 113) of the cut portion 14 a in the direction (width direction) perpendicular to the extending direction of the vibrating arm portion 12. And the distance to the tip of the cut portion 14a. The tip of the cut portion 14a is a portion where the first surface 141a and the second surface 142a are in contact with each other.

  In addition, since the cut portion 14a has a shape that moves away from the vibrating arm portion 12 as it goes inward of the base portion 11, even if the cut depth of the cut portion 14a is increased, the width in the width direction of the base portion 11 is minimized as compared with the related art. Since the length can be increased, the impact on the impact resistance due to the provision of the cut portion 14a can also be suppressed.

  In particular, when the conductive adhesive 31 is applied in a circular shape around the vicinity of the apex 112a, and the first surface 141a of the cut portion 14a that does not contact the conductive adhesive 31 is arcuate, the conductive adhesive 31 The peripheral edge and the first surface 141a draw a substantially concentric circle. Therefore, the first surface 141a extends to the inside of the base portion 11 while maintaining a substantially constant distance with respect to the conductive adhesive 31. Therefore, even if the cutting depth of the cutting portion 14a is sufficiently increased, The surface 141a does not come into contact with the conductive adhesive 31, and this has a further remarkable effect.

  In other words, the cut 14a provided in the base 11 to prevent vibration leakage gradually increases the cut amount 143 (shown on the cut 14b side) from the vibrating arm 12 side of the base 11 toward the electrode pad 22a. The shape is increasing. Here, the cut amount 143 is a distance from the base end (third side 113) of the cut portion 14a to the first surface 141a in a direction perpendicular to the extending direction of the vibrating arm portion 12. By setting it as the shape of such a notch part 14a, it can suppress that the conductive adhesive 31 reaches | attains the base part center side end surface of the notch part 14a, and the conductive adhesive 31 inhibits a vibration. Moreover, even if the cutting amount 143 is large, since there are few regions in which the length in the width direction of the base 11 is small, the impact resistance against dropping or the like is excellent.

  FIG. 4 is a plan view of the resonator element according to the second embodiment. Hereinafter, a description will be given based on FIG.

  The vibration element 40 of the second embodiment is different from the first embodiment in the shapes of the cut portions 44a and 44b. The cut portion 44 a has a first surface 441 a that is on the first side 111 side and does not contact the conductive adhesive 31, and a second surface 442 a that is on the second side 112 side and contacts the conductive adhesive 31. The cut portion 44 b has a first surface 441 b that is on the first side 111 side and does not contact the conductive adhesive 31, and a second surface 442 b that is on the second side 112 side and contacts the conductive adhesive 31. Since the cut portions 44a and 44b are symmetrical with each other, that is, both have the same shape, the cut portion 44a will be described below.

  The cut portions 44a and 44b are symmetrical in terms of design, but in practice, the manner of attaching the residue after etching is not symmetrical. This is because the wet etching of quartz is anisotropic etching in which the etching amount varies depending on the crystal axis. The same applies to other embodiments.

  In the cut portion 44 a, both the first surface 441 a and the second surface 442 a have a shape that moves away from the vibrating arm portion 12 as it goes inside the base portion 11. More specifically, the first surface 441 a has an arc shape along the periphery of the conductive adhesive 31, and the second surface 442 a extends along a direction oblique to the extending direction of the vibrating arm portion 12. It is straight.

  The shape of the second surface 442a is not limited to a linear shape, but any shape such as an arc shape, an elliptical arc shape, a curved shape, a polygonal line shape, or the like that moves away from the vibrating arm portion 12 as it goes inside the base portion 11. But you can.

  Next, the operation and effect of the vibration element 40 will be described with reference to FIGS.

  In the first embodiment shown in FIG. 1, only the first surface 141 a has a shape that moves away from the vibrating arm portion 12 as it goes inside the base portion 11, and the second surface 142 a is in a direction perpendicular to the extending direction of the vibrating arm portion 12. A straight line along. Therefore, as shown in the drawing, the tip of the cut portion 14a where the first surface 141a and the second surface 142a are in contact cannot be provided on the second side 112 side than the base end of the cut portion 14a.

  On the other hand, in the second embodiment shown in FIG. 4, both the first surface 441 a and the second surface 442 a have a shape that moves away from the vibrating arm portion 12 as it goes inside the base portion 11. Therefore, as shown in the drawing, the tip end of the cut portion 44a where the first surface 441a and the second surface 442a are in contact can be provided on the second side 112 side of the base end of the cut portion 44a.

  Therefore, according to the second embodiment, the area of the base 11 that contributes to vibration can be increased by increasing the area of the base 11 on the first side 111 side from the first surface 441a. Can be reduced. In other words, the vibration leakage can be suppressed by the cut portion 44a while taking a wide place for exchanging the resonance energy of the vibrating arm portion 12, and thus the CI can be further reduced.

  Moreover, even if the cutting depth of the cut portion 44a is increased by providing the tip of the cut portion 44a where the first surface 441a and the second surface 442a contact each other on the second side 112 side with respect to the base end of the cut portion 44a. Since the minimum length in the width direction of the base portion 11 can be further increased as compared with the first embodiment, it is possible to further suppress the influence on the impact resistance due to the provision of the cut portion 44a.

  In other words, in the second embodiment, the second surface 442 a on the electrode pad 22 a side of the cut portion 44 a has an inclination so as to be separated from the vibrating arm portion 12 toward the center of the base portion 11. By adopting such a shape, the region where the width of the base portion 11 gradually changes as the cut portion 44a goes from the vibrating arm portion 12 side to the electrode pad 22a side can be taken long, and leakage of vibration energy can be made more efficient. The shape of the base 11 that can be well prevented and is also preferable for impact resistance is obtained.

  Other configurations, operations, and effects of the second embodiment are the same as those of the first embodiment.

  FIG. 5 is a plan view of the resonator element according to the third embodiment. Hereinafter, a description will be given based on FIG.

  The vibration element 50 according to the third embodiment is different from the second embodiment in that it includes a protrusion 53 and a slit 54. The protrusion 53 is in the middle of the pair of vibrating arms 12 and extends from the base 11 along the vibrating arms 12. In addition, the protrusion 53 is provided in an isosceles triangle shape as a whole so that the width increases as the width advances from the distal end to the proximal end. A slit 54 is provided at the tip of the protrusion 53 along the extending direction. The slit 54 penetrates in the thickness direction of the protrusion 53. The width of the protrusion 53 is the length of the protrusion 53 in a direction perpendicular to the extending direction of the vibrating arm 12.

  In the third embodiment, excitation electrodes 21 a and 21 b are formed on the side surface of the vibrating arm portion 12 by a lift-off method using a sputtering technique and a photolithography technique. At this time, the slit 54 serves to separate the excitation electrode 21a on the side surface of the first vibrating arm portion 12a from the excitation electrode 21b on the side surface of the second vibrating arm portion 12b (see Patent Document 3).

  Other configurations of the third embodiment are the same as those of the second embodiment. Even with the configuration of the third embodiment, the same operations and effects as those of the second embodiment can be achieved.

  Next, the vibration element 50 will be described more specifically. In the description here, “length” is the distance in the extending direction of the vibrating arm 12, and “width” is the distance in the direction perpendicular to the extending direction of the vibrating arm 12.

  The outer shape of the crystal vibrating piece 15 and the grooves 13a and 13b are formed by using a technique such as wet etching on a crystal Z plate wafer, for example. Excitation electrodes 21a and 21b are formed on the side surfaces of the vibrating arm portion 12 and the groove portions 13a and 13b by using a film forming method such as vapor deposition or sputtering. On the base 11, two electrode pads 22a and 22b having different polarities are formed. The electrode pads 22a and 22b are connected to the excitation electrodes 21a and 21b, respectively. Further, as shown in FIG. 3, the electrode pads 22a and 22b are connected to the electrode pads 33 of the element mounting member 32 constituting the package via a conductive adhesive 31 or the like, and predetermined wiring in the package (not shown). ) To an external terminal (not shown) of the package.

  The vibration element 50 is designed to resonate at 32.768 kHz, for example. In particular, the vibration element 50 has a total length of 1.17 mm, which corresponds to miniaturization. The thickness of the vibration element 50 is approximately the same as the thickness of the crystal wafer to be used. lmm. The length 61 of the vibrating arm portion 12 is 0.96 lmm, the width 62 of the vibrating arm portion 12 is 0.0486 mm, and the width 69 between the center of the first vibrating arm portion 12a and the center of the second vibrating arm portion 12b. Is 0.2162 mm. The length 63 of the base 11 is 0.208 mm, and the width 64 of the base 11 is 0.347 mm.

  The base portion 11 is formed with cut portions 14a and 14b. In the third side 113 of the base portion 11, the length 65 from the vibrating arm portion 12 side to the opening end of the cut portion 14a is 0.0575 mm, the length 66 of the open end of the cut portion 14a is 0.0465 mm, and the length of the cut portion 14a is A length 67 from the opening end to the tip of the cut portion 14a is 0.029 mm. The second surface 142a on the electrode pad 22a side of the cut portion 14a is inclined toward the electrode pad 22a side toward the center of the base portion 11. The maximum cut amount 68 of the cut portion 14a is 0.119 mm. The first surface 141a on the vibrating arm 12 side of the cut portion 14a has an arc shape. The cut portion 14b is the same as the cut portion 14a.

  Next, the electrical characteristics of the vibration element 50 will be described.

  The vibration element 50 had a resonance frequency of 40.3 kHz and a CI of 52 kΩ. Further, the temperature dependence of the resonance frequency was an upwardly convex quadratic curve (temperature is on the horizontal axis and resonance frequency is on the vertical axis), and the apex temperature was 30 ° C.

  Here, the conductive adhesive 31 was intentionally brought into contact with the first surface 141a of the cut portion 14a, and the vibration element was mounted in this state to measure the electrical characteristics. As a result, although the resonance frequency was almost the same as 40.2 kHz, CI increased to 80 kΩ, and the temperature dependence peak temperature of the resonance frequency decreased to 18 ° C. Thus, it became clear that when the conductive adhesive 31 touches the first surface 141a of the cut portion 14a, the electrical characteristics of the vibration element deteriorate.

  On the other hand, since the vibration element 50 has the shape of the cut portion 14 a that does not overlap the application region of the conductive adhesive 31, the above-described problem is unlikely to occur. In addition, as compared with the related art, even if the cut amount of the cut portion 14a is increased, the minimum width of the base portion 11 is not easily reduced, so that the strength for supporting the vibrating arm portion 12 is less deteriorated.

  FIG. 6 is a plan view of the resonator element according to the fourth embodiment. Hereinafter, a description will be given based on FIG.

  The vibration element 70 according to the fourth embodiment is different from the first embodiment in that the cut portions 74a and 74b have third surfaces 743a and 743b, respectively. That is, the notch 74a has a third surface 743a that does not contact the adhesive 31 between the first surface 741a and the second surface 742a. The notch 74b has a third surface 743b that does not contact the adhesive 31 between the first surface 741b and the second surface 742b.

  If there is no third surface 743a, a portion where the first surface 741a and the second surface 742a, which are the tips of the cut portions 74a, are pointed. However, in the fourth embodiment, by providing the third surface 743a between the first surface 741a and the second surface 742a, the tip of the cut portion 74a is not sharpened, and stress concentration at the tip of the cut portion 74a is alleviated. Since it can, impact resistance can be improved. In particular, as shown in the figure, when the third surface 743a is parallel to the extending direction 120 of the vibrating portion 12, the angle formed by the first surface 741a and the third surface 743a and the second surface 742a and the third surface 743a are illustrated. Since the stress concentration at the tip of the cut portion 74a can be further relaxed, the impact resistance can be further improved. The same applies to the notch 74b.

  Other configurations of the fourth embodiment are the same as those of the first to third embodiments. Even with the configuration of the fourth embodiment, the same operations and effects as those of the first to third embodiments are achieved.

  Although the present invention has been described with reference to the above embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention. Further, the present invention includes a combination of some or all of the configurations of the above-described embodiments as appropriate.

  In addition to the tuning fork type vibration element described above, the present invention can be used for a crystal vibration element such as a contour sliding vibration element.

DESCRIPTION OF SYMBOLS 10 Vibration element 11 Base 111 First side 112 Second side 112a, 112b Vertex 113 Third side 114 Fourth side 12 Vibration arm part 120 Extension direction 12a First vibration arm part 12b Second vibration arm part 13a, 13b Groove part 14a , 14b Cut portion 141a, 141b First surface 142a, 142b Second surface 143 Cut amount 15 Crystal vibrating piece 21a, 21b Excitation electrode 22a, 22b Electrode pad 23a, 23b Frequency adjustment metal film 31 Conductive adhesive 32 Element mounting member 33 Electrode pad 40 Vibration element 44a, 44b Cut part 441a, 441b First surface 442a, 442b Second surface 50 Vibration element 53 Projection part 54 Slit 61, 63, 65, 66, 67 Length 62, 64, 69 Width 68 Maximum Cut amount 70 Vibration element 74a, 74b Cut portion 7 41a, 741b First surface 742a, 742b Second surface 743a, 743b Third surface 100 Vibration element 101 Vibration arm portion side end surface 102 Base portion central side end surface 114a, 114b Cut portion 200 Vibration element 202 Base portion center side end surface 214a, 214b Cut portion

Claims (4)

A base, a vibration portion extending from the base, a cut portion formed in the base, and an adhesive for fixing the base to an element mounting member;
In the crystal resonator element with
The base portion has a quadrangular shape having a first side provided with the vibrating portion, a second side facing the first side, and a third side and a fourth side formed with the cut portion and facing each other. Yes, fixed to the element mounting member via the adhesive applied in a circular shape around each of the two apexes sandwiching the second side,
The cut portion is Ri shape der away from the vibrating unit as one proceeds inwardly of the base portion, a first surface which is not in contact with the adhesive be in the first window side, said there to the second window side A second surface in contact with the adhesive,
The first surface has an arc shape along the periphery of the adhesive.
A crystal resonator element characterized by the above. Both the first surface and the second surface are shaped to move away from the vibrating portion as they go inside the base portion.
The crystal resonator element according to claim 1 . The cut portion further includes a third surface that does not contact the adhesive between the first surface and the second surface.
The crystal resonator element according to claim 1 or 2 . The third surface is parallel to the extending direction of the vibrating portion;
The crystal resonator element according to claim 3 .

Images