JP2014158183A - Crystal oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact crystal oscillator which can suppress degradation of oscillation characteristics and reduction in connection strength caused by stress concentration on a mounting part so as to maintain excellent oscillation characteristics over a long period of time.SOLUTION: A crystal oscillator comprises: a crystal oscillation piece having a crystal diaphragm and two mounting electrodes which are provided in the vicinity of a peripheral part of the crystal diaphragm; a holder on which the crystal oscillation piece is mounted; two base electrodes formed on an upper face of the holder and electrically connected to the two mounting electrodes, respectively; and a support part formed on the upper face of the holder and supporting the crystal oscillation piece. One of the base electrodes has: a deformably formed first deformation part which is located between the upper face of the holder and a lower face of the crystal oscillation piece facing the upper face of the holder; a first fastening part fastened to the upper face of the holder; and a first gap formed between the holder upper face side of the first deformation part and the upper face of the holder.

Description

  The present invention relates to a crystal resonator.

  Various materials are known as materials that can be expected to have a piezoelectric effect. Conventionally, quartz that can obtain a stable and accurate frequency is preferably used. A crystal resonator is known as one of devices using this crystal.

  This crystal unit is mainly composed of a crystal resonator element in which an electrode film is formed on a crystal diaphragm processed into a predetermined shape, and a holder for packaging the crystal resonator element in an airtight state. Built in various electronic devices. In recent years, these electronic devices are required to be reduced in size and size, and accordingly, further reduction in the size of crystal units is also required.

  Therefore, it is required to reduce the mounting area when mounting the quartz crystal resonator element on the cage. Therefore, there is a joining means using metal as a crystal piece mounting means for maintaining good vibration characteristics for a long period of time. A metal bump is ultrasonically fixed to the base electrode on the cage, and the crystal vibrating piece is pressurized while applying ultrasonic waves thereon, whereby the mounting electrode and the metal bump on the crystal vibrating piece are joined. Metal bumps are arranged at two locations near the outer periphery of the crystal piece.

  However, according to this, the following problems are pointed out. In the case of metal bonding, since the bonding strength is high and the rigidity of the bonding member is high, distortion occurs due to the stress between the two outer peripheral portions where the metal bumps are arranged due to the difference in expansion coefficient between the crystal piece and the cage body. This propagates to the vibration region and deteriorates the vibration characteristics, in particular, the frequency temperature characteristic that is originally a cubic curve in the AT-cut crystal resonator.

  For this problem, in the quartz crystal holding structure in which the extraction electrode is extended from the excitation electrode arranged at the center of the vibration region of the rectangular crystal vibrating piece to the crystal piece outer peripheral portion at two locations, one of the two outer peripheral portions is A structure has been proposed in which a mechanical end is electrically connected by metal bonding to be a fixed end, and the other of the two outer peripheral portions is electrically connected by wire bonding to be a free end (see Patent Document 1).

JP 2004-80711 A

However, the following problems remain in the conventional crystal unit described above.
According to wire bonding, after first connecting the mounting electrode on the crystal and the bonding ball, the wire is pulled upward, then the wire is bent with a predetermined curvature to form a loop shape, and the base electrode on the cage The wire is stretched toward the base, the base electrode and the wire are second connected, and the wire is cut. Since the wire is elastically deformed and bent partly by plastic deformation, stress concentrates on the first connected portion serving as a fulcrum and the fixed end that fixes the quartz crystal vibrating piece, leading to a decrease in connection strength at these two points. I will. This causes a long-term decline in electrical connection and impairs reliability. Further, the stress concentration at the first connected portion and the fixed end is greatly influenced by the vibration characteristics, and becomes a source of unnecessary vibration.

  Further, after the bonding is finished, stress remains in the direction of lifting the quartz crystal vibrating piece due to the spring back of the wire. This causes frequency fluctuations.

  Furthermore, wire bonding is disadvantageous in terms of miniaturization of the crystal resonator. This is because an area and height for accommodating the bonding wire are required. It is said that the wire length is several hundred μm or more and the loop height is 70 μm or more, which is about 1/5 of the vibrator size. In order to accommodate this size, it is necessary to increase the volume by increasing the vertical and horizontal height dimensions of the cage. However, the increased volume is only used to store the wire, and the rest is a useless space.

  Here, reducing this useless space leads to miniaturization. However, if the curvature of the wire loop is reduced for that purpose, the reliability is lowered and the frequency fluctuates more for the reasons described above.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a miniaturized crystal resonator while effectively maintaining vibration characteristics.

The present invention provides the following means in order to solve the above problems.
A quartz crystal resonator according to the present invention includes a quartz crystal vibrating plate, a quartz crystal vibrating piece having two mounting electrodes provided near the periphery of the quartz crystal vibrating plate, a holder for mounting the quartz crystal vibrating piece, A crystal unit comprising two base electrodes formed on the upper surface of the cage and electrically connected to the two mounting electrodes, respectively, and a support formed on the upper surface of the cage and supporting the crystal vibrating piece The first base electrode is located between the upper surface of the cage and the lower surface of the quartz crystal vibrating piece facing the upper surface of the cage, and is formed to be deformable. And a first gap between the upper surface side of the cage and the upper surface of the cage in the first deformed portion. It is characterized by having.

  In the crystal resonator according to the present invention, the first deformable portion can be formed by not fixing a part of one base electrode to the cage. One base electrode can be deformed by the first deforming portion without being restricted by the cage. It is possible to reduce the stress applied to the crystal vibrating piece.

The deformation of the crystal vibrating piece with respect to the temperature change occurs based on the difference in thermal expansion coefficient between the cage and the crystal vibrating piece between the support portion and the fixing portion. However, in the present invention, since the first deforming portion is deformed, deformation of the crystal vibrating piece is suppressed, and stress on the crystal vibrating piece can be reduced. As a result, the temperature characteristics can be kept good.
Further, since the crystal resonator element is mounted on the holder between the lower surface of the crystal resonator element and the upper surface of the holder, the height of the crystal resonator can be reduced.

  The crystal resonator according to the present invention is characterized in that the first deforming portion is formed of a thin film. In the crystal resonator according to the present invention, since the first deformable portion that can be deformed in the stress reduction direction is thinned, the spring back at the time of mounting is eliminated, so that the stress applied to the crystal resonator element after mounting is reduced. The Therefore, there is no influence on the frequency characteristics, and vibration characteristics close to the theoretical values can be obtained. The crystal resonator according to the present invention is characterized in that the first gap is on a line connecting the first fixing portion and the support portion. In the crystal resonator according to the present invention, since stress is generated between the support portion and the first fixing portion as described above, deformation in the first deformation portion is caused by pulling or compression of the deformation portion and voids. It becomes a deformation of the play in the thickness direction accompanying the formation, and the deformation due to the side shake is eliminated. In the case of deformation due to lateral vibration, the first deformable portion had to be reduced in length in the deformation direction to suppress stress application to the quartz crystal vibrating piece, but in the present invention, the first deformable portion can be widely formed. Therefore, it is advantageous in terms of electrical resistance and mechanical strength.

  In the crystal resonator according to the present invention, the support portion is a connection electrode that connects one mounting electrode and the other base electrode. In the crystal resonator according to the present invention, the crystal resonator element is mechanically fixed to the holder by connecting the mounting electrode and the other base electrode with the connection electrode without providing a gap on the other base electrode side. can do. In addition, since it is not necessary to provide a support portion other than the mounting electrodes, the quartz crystal resonator element can be reduced in size, and as a result, the area of the cage can be reduced. In addition, the first fixing portion according to the present invention is disposed between a lower surface of the crystal vibrating piece and an upper surface of the cage.

  In the crystal resonator according to the present invention, when the crystal resonator is viewed from the upper surface, the first fixing portion is disposed on the lower surface of the crystal resonator element. Since it is not necessary to provide the first fixing portion outside the crystal vibrating piece, the area of the cage can be reduced.

  Further, in the crystal resonator according to the invention, the support portion is electrically insulated from the two mounting electrodes, and the other base electrode is between the upper surface of the cage and the lower surface of the crystal vibrating piece. A second deformable portion that is formed to be deformable and a second fixing portion that is fixed to the upper surface of the retainer, and the upper surface side of the retainer of the second deformable portion; A second gap is provided between the upper surface of the cage and the upper surface of the cage. The support part is formed other than the other base electrode, and one base electrode and the other base electrode can be similarly deformed, and the influence of the connection part between the base electrode and the mounting electrode on the vibration of the quartz crystal vibrating piece is suppressed. Can do. As a result, since the shape of the quartz crystal resonator element can be simplified, it is possible to suppress the occurrence of the secondary vibration and facilitate the improvement of the vibration characteristics.

  According to the crystal resonator according to the present invention, the generation of stress in the crystal resonator element can be suppressed. Therefore, the influence on the mechanical strength and vibration can be reduced, and the vibration characteristics can be improved.

It is a figure for demonstrating embodiment which concerns on this invention, Comprising: It is a disassembled perspective view of the surface mount-type crystal resonator which has a thickness shear vibration piece. FIG. 2 is a top view when a lid is removed from the crystal resonator shown in FIG. 1. FIG. 3 is a cross-sectional view of the crystal resonator taken along line A-A ′ shown in FIG. 2. FIG. 4 is a top view when the lid is removed from the crystal unit shown in FIG. 1 and is a modification of FIG. 2. FIG. 6 is a top view when the lid is removed from the crystal unit shown in FIG. 1, and is a modification of FIGS. 2 and 4. FIG. 6 is a top view when a lid is removed from the crystal unit shown in FIG. 1, and is a modification of FIGS. 2, 4, and 5. FIG. 3 is a cross-sectional view of the crystal resonator taken along line A-A ′ shown in FIG. 2, which is a modification of FIG. 2. FIG. 9 is a cross-sectional view of the crystal resonator taken along the line A-A ′ shown in FIG. 2, and is a modification of FIGS. 2 and 7. FIG. 7 is a top view when the lid is removed from the crystal unit shown in FIG. 1, and is a modification of FIGS. 2, 4, 5, and 6. FIG. 10 is a cross-sectional view of the crystal resonator taken along line A-A ′ shown in FIG. 9. FIG. 10 is a cross-sectional view of the crystal resonator taken along line B-B ′ shown in FIG. 9. FIG. 10 is a cross-sectional view of the crystal resonator taken along line B-B ′ shown in FIG. 9, which is a modification of FIG. 11. FIG. 10 is a top view when the lid is removed from the crystal unit shown in FIG. 1, and is a modification example of FIGS. 2, 4, 5, 6, and 9.

  Hereinafter, embodiments according to the present invention will be described with reference to FIGS. 1 to 14. In the present embodiment, a surface-mounted crystal resonator having a thickness-shear resonator element (crystal resonator element) will be described as an example.

(Embodiment 1)
FIG. 1 is an exploded perspective view of a surface-mounted crystal resonator having a thickness-shear resonator element according to this embodiment. FIG. 1 is an exploded perspective view of the crystal resonator.

  As shown in FIG. 1, the crystal resonator of the present embodiment includes a crystal vibrating plate 31, two mounting electrodes 33 provided near the periphery of the crystal vibrating plate 31, and a holder for mounting the crystal vibrating piece 3. And two base electrodes 12 formed on the upper surface of the cage and electrically connected to the two mounting electrodes 33, respectively.

  Further, in the present embodiment, there is a support portion that is formed on the upper surface of the cage and supports the crystal vibrating piece, and one base electrode faces the upper surface of the cage and the upper surface of the holder of the crystal vibrating piece. It has a 1st deformation | transformation part which is located between a lower surface and is formed so that a deformation | transformation is possible, and a 1st adhering part adhering to the upper surface of a holder | retainer.

A first gap is provided between the upper surface side of the cage and the upper surface of the cage in the first deformable portion.
The retainer is formed in a box shape in which a holding container 1 and a lid 2 are welded at a sealing portion 11 and laminated in two layers. Further, the holding container 1 and the lid 2 form an internal cavity. A crystal vibrating piece 3 is mounted in the cavity.

  The quartz crystal resonator element 3 is electrically connected to the quartz diaphragm 31 obtained by slicing the quartz crystal, and the two excitation electrodes 32 and the two excitation electrodes 32 respectively formed on the upper and lower surfaces of the quartz diaphragm 31. And an electrode film having two mounting electrodes 33. Each mounting electrode 33 is electrically connected to a different base electrode 12 disposed on the upper surface of the bottom of the holding container 1 located at the bottom of the cavity.

  The arrangement position of the crystal vibrating piece 3 on the holding container 1 is shown in FIG. FIG. 2 is a view of the lid 2 removed from the crystal unit of FIG.

  In addition, the crystal vibrating piece 3 includes an excitation electrode 32 disposed at the center of a quartz crystal diaphragm 31 having a rectangular shape in plan view, a mounting electrode 34 and a mounting electrode 35 disposed at the peripheral edge. The quartz crystal vibrating piece 3 is arranged at the substantially central portion of the holding container bottom portion 17 so that the mounting electrode A34 and the deformable portion 15, and the mounting electrode B35 and the base electrode B16 overlap.

  The holding container 1 includes a holding container bottom 17 and a holding container side wall that surrounds the holding container bottom 17 and stands upright at the peripheral edge of the holding container bottom 17. Further, a sealing portion 11 for joining the holding container 1 and the lid 2 is formed on the upper surface of the holding container side wall. One base electrode 13 (one base electrode) and the other base electrode 16 (the other base electrode) are disposed on the upper surface of the holding container bottom 17.

  The base electrode 13 has a fixing portion 14 (first fixing portion) fixed to the holding container bottom portion 17 and a deformable portion 15 (first deforming portion) formed to be deformable. In addition, a first gap is provided between the upper surface side of the holding container bottom 17 in the deformable portion 15 and the holding container bottom 17. Therefore, the deformable portion 15 is separated from the upper surface of the holding container bottom portion 17. The fixing portion 14 is formed in close contact with the upper surface of the holding container bottom portion 17. The base electrode 16 is formed in close contact with the upper surface of the holding container bottom 17. Moreover, in this embodiment, the adhering part 14 and the deformation | transformation part 15 are formed on a straight line.

  FIG. 3 shows the connection relationship between the crystal vibrating piece 3 and the electrode of the holding container 1. FIG. 3 is a cross-sectional view taken along the line A-A ′ of FIG. 2. In FIG. 3, the sealing part 11 is omitted.

  The holding container 1 is a box-shaped container having a holding container side wall 18 at the peripheral edge of the upper surface of the holding container bottom 17 and having a recess at the center. An external electrode 19 and an external electrode 20 are disposed on the lower surface of the holding container bottom 17 and serve as connection terminals for an external wiring board. The external electrode 19 is electrically connected to the fixing portion 14 disposed on the upper surface of the holding container bottom 17 through a through electrode 21 that penetrates the holding container bottom 17. Furthermore, the adhering portion is connected to the deformable portion 15 that can be deformed by having the first gap between the holding portion bottom portion 17 and the fixing portion. Similarly, the external electrode 20 is electrically connected to the base electrode 16 disposed on the upper surface of the holding container bottom 17 via a through electrode (not shown).

  The quartz crystal vibrating piece includes a mounting electrode 34 and a mounting electrode 35 that are disposed at both left and right ends of the crystal vibrating plate 31 so that the upper surface and the lower surface are electrically connected via the side surfaces. The mounting electrode 34 is electrically connected to the deformable portion 15 via the connection electrode 36. The mounting electrode 35 is electrically connected and fixed via the base electrode 16 and the connection electrode 37. In the present embodiment, the support portion is a connection electrode that connects the mounting electrode 35 and the base electrode 16.

  Here, the fixing portion 14 is arranged on a line connecting the connection electrode 36 and the connection electrode 37. Further, the deformable portion 15 and the first gap are located on a line connecting the fixing portion 14 and the connection electrode 37 that is the support portion. In this case, the deformation at the deforming portion 15 is deformation due to pulling or compression of the deforming portion and play in the thickness direction accompanying the formation of the gap, and there is no deformation due to side shake. In the case of deformation due to lateral vibration, it was necessary to suppress the stress application to the crystal vibrating piece by reducing the length in the deformation direction of the deformed portion, but according to the present embodiment, the deformable portion 15 can be widely formed. This is advantageous in terms of electrical resistance and mechanical strength.

  The mounting electrode 34 and the mounting electrode 35 are laminated films in which a base layer is formed of Cr, Ni, Ti as an adhesion layer to the quartz crystal plate 31 and Au is formed as an upper layer on the adhesion layer. Each layer is a thin film having a thickness of about 10 nm to 200 nm. The connection electrode 36 and the connection electrode 37 are metal electrodes such as Au, Au—Sn, and solder. The connection electrode 36 and the connection electrode 37 have a cylindrical shape, the height of each connection electrode is several μm to several tens of μm, and the diameter is about 20 μm to 100 μm. The fixing portion 14 and the base electrode 16 may be a single Au layer, or a base layer may be formed of Cr, Ni, Ti, Mo, W, or the like as an adhesion layer with the holding container bottom portion 17, and Au may be formed as an upper layer on the adhesion layer. Is a laminated film formed by The deformable portion 15 is a laminated film having an underlayer similar to the fixed portion, or an Au single layer.

Here, the deformable portion 15 is formed of a thin film and has a thickness of 1 μm to 10 μm. If the thickness of the deforming portion 15 is in the above-described range, the deforming portion 15 can be easily plastically deformed by the pressure applied when mounting the crystal vibrating piece. Therefore, the crystal vibrating piece is mounted while relaxing the stress. It becomes possible. In the past fixing of the mounting electrode and the connection electrode by metal bonding, the stress is concentrated on the fixing portion, so that the vibration characteristics are greatly changed, which is a source of unnecessary vibration. However, according to this structure, since the stress is relieved by plastic deformation of the deformable portion 15, unnecessary vibrations are generated in the portion where the mounting electrode 34 and the connection electrode 36 are fixed and the portion where the mounting electrode 35 and the connection electrode 37 are fixed. Occurrence is eliminated and vibration characteristics are improved. In addition, since the deformation amount in the deformation part 15 is about several tens of nm or less calculated from the difference in thermal expansion coefficient, the void amount may be minute. Even if a gap of about several μm is provided due to manufacturing restrictions, the gap can be formed while suppressing the useless space in the thickness direction that has been generated in the conventional wire bonding, and therefore, the size can be reduced.
The connection electrode 36 and the connection electrode 37 are formed by metal bumps or the like.

A method for manufacturing a crystal resonator according to this embodiment will be described.
First, the crystal vibrating piece 3 is formed. The crystal vibrating piece 3 forms an electrode film pattern on the crystal vibrating plate 31.

  The holding container 1 is formed in a separate process from the above. The holding container 1 is made of, for example, glass, silicon, ceramics or the like. The holding container 1 forms a holding container side wall 18, and forms a through electrode 21 in the holding container bottom 17.

  Next, the base electrode 16 and the base electrode 13 are formed. The base electrode 16 is formed by patterning a metal film by sputtering or the like.

  The base electrode 13 can be formed by previously forming a thin metal plate in the shape of the fixing portion 14 and the deforming portion 15 and fixing the upper surface of the holding container bottom portion 17 and the fixing portion 14 by thermocompression bonding, ultrasonic welding, or the like. . The base electrode 13 can be formed by other methods. First, a resist is applied to a portion of the holding container bottom 17 corresponding to the deformed portion 15, that is, a portion where the first gap is formed, and then wet plating is performed on the resist and a portion corresponding to the fixing portion 14 of the holding container bottom 17. To deposit a thick metal. Thereafter, the resist is peeled off.

  With the above-described forming method, it is possible to form a shape in which the deforming portion 15 is free from the holding container bottom portion 17 and the first gap while the fixing portion 14 is fixed to the holding container bottom portion 17. Next, the crystal vibrating piece 3 is mounted on the holding container 1. The quartz crystal vibrating piece 3 is held using mounting members such as a metal connection electrode 36 and a connection electrode 37. As a mounting method, heat pressure bonding, ultrasonic pressure bonding, or the like can be used. At this time, the mounting electrode 36 and the mounting electrode 37, and further, Au on the surface layers of the deformable portion 15 and the base electrode 16 are metal-bonded to the connection electrode 36 and the connection electrode 37 by mutual diffusion or surface activation. . The quartz crystal resonator element is firmly fixed to the holding container by the size of the connection electrode and the metal bond between each electrode and the connection electrode. Note that the connection electrode 37 may be formed of a conductive resin. Thereby, each mounting electrode, the base electrode 16, and the deformation | transformation part 15 which were formed in the lower surface of the crystal vibrating piece 3 are joined via each connection member.

  In addition, when forming the deformation | transformation part 15 using a resist, a resist is peeled after the crystal vibrating piece 3 is mounted. Thereby, a 1st space | gap is formed reliably.

  Thereafter, the holding container 1 and the lid 2 are joined via a sealing portion. The lid 2 is made of, for example, glass, silicon, ceramics or the like. Various joining methods are selected depending on the type of holding container 1. In addition, various materials are selected for the sealing portion depending on the bonding method. For example, when the holding container 1 and the lid 2 are made of glass, the sealing portion is formed of a metal film, and the holding container 1 and the lid 2 are joined by anodic bonding.

  Thus, a crystal resonator is manufactured. Note that the manufacturing method is not necessarily limited to the present embodiment.

Next, a modification of this embodiment will be described.
As a modification, the deformation portion 15 is formed of a thin film, and the thickness of the deformation portion 15 is 0.05 μm to 1 μm. In addition, about another structure, it is the same as that of this embodiment.

  If the thickness of the deforming portion 15 is in the above-described range, the deforming portion 15 can be easily plastically deformed by the pressure applied when mounting the crystal vibrating piece. Therefore, the crystal vibrating piece is mounted while relaxing the stress. It becomes possible. Unnecessary vibration is not generated in the portion where the mounting electrode 34 and the connection electrode 36 are fixed and the portion where the mounting electrode 35 and the connection electrode 37 are fixed, and the vibration characteristics are improved. Furthermore, the deformation portion 15 is formed thinly and can be easily plastically deformed even with respect to the difference in expansion degree between the holding container and the quartz crystal vibrating piece due to temperature change, so that the stress can be relaxed. Therefore, it becomes possible to obtain a frequency temperature characteristic close to the theoretical value.

  A method for forming the deformable portion 15 will be described. After applying a resist to a portion of the upper surface of the holding container bottom 17 corresponding to the deformable portion 15, that is, a portion where the first gap is formed, sputtering is performed on the resist and a portion corresponding to the fixing portion 14 of the holding container bottom 17. To deposit and pattern the metal. Then, it forms by peeling a resist. While the fixing portion 14 is fixed to the holding container bottom portion 17, the deformable portion 15 can have a shape free from the holding container bottom portion 17 and the first gap. Note that the resist is peeled after the crystal vibrating piece 3 is mounted.

  As described above, since the deformable portion 15 that can be deformed in the stress reduction direction is thinned, there is no springback at the time of mounting, so that the stress applied to the crystal vibrating piece after mounting is reduced. Therefore, there is no influence on the frequency characteristics, and vibration characteristics close to the theoretical values can be obtained.

  Further, since the deformation is facilitated by reducing the thickness, the length of the base electrode 13 can be shortened, thereby enabling a reduction in size.

(Embodiment 2)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 4 is a view showing a modification of the crystal resonator of FIG. 1, and is a view of the crystal resonator of FIG. 1 with the lid 2 and the crystal resonator element 3 removed and viewed from above. However, the arrangement of the crystal vibrating piece 3 is indicated by a dotted line. Note that the description of the same configuration as that of the first embodiment is omitted.

  In the present embodiment, the deformable portion 15 is arranged in a direction perpendicular to the line connecting the connection electrode 36 and the connection electrode 37. Therefore, the deformable portion 15 can be deformed so that it can be easily swung in the direction of twisting or approaching or separating each connection electrode, with the portion connected to the fixing portion 14 as a fulcrum. Since the degree of freedom of deformation of the deformable portion 15 is high, a high stress reduction effect can be exhibited. In the present embodiment, the portion of the fixing portion 14 that connects to the deformable portion 15 is disposed in a direction perpendicular to the deformable portion 15, but is formed with an angle with respect to the deformable portion 15. It only has to be.

(Embodiment 3)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 5 is a view showing a modification of the crystal resonator of FIG. 1, and is a view as seen from above, with the lid 2 and the crystal resonator element 3 removed from the crystal resonator of FIG. However, the arrangement of the crystal vibrating piece 3 is indicated by a dotted line. In addition, description is abbreviate | omitted about the structure similar to each embodiment.

  The base electricity 13 and the base electrode 16 are diagonally arranged on the upper surface of the holding container bottom 17. Although not shown, the mounting electrode 34 and the mounting electrode 35 are arranged diagonally to the crystal vibrating piece 3 in accordance with the arrangement of the base electrode 13 and the base electrode 16. In order to mount the crystal vibrating piece 3, a connection electrode 36 is fixed to the base electrode 13, and a connection electrode 37 is fixed to the base electrode 16. The base electrode 13 includes a fixing portion 14 that is fixed to the upper surface of the holding container bottom portion 17 and a deformation portion 15 that is separated from the upper surface of the holding container bottom portion 17.

  In the present embodiment, the deformable portion 15 is disposed on a line connecting the connection electrode 36 and the connection electrode 37. In the diagonal arrangement of each base electrode, the distance between the connection electrode 36 and the connection electrode 37 becomes longer, so that the stress between the connection electrodes increases. However, the stress between the connection electrodes can be relaxed by the expansion and contraction of the deformable portion 15. The diagonal arrangement of the base electrodes increases the distance between the mounting electrodes. Thereby, it becomes easy to ensure the area on the crystal vibrating piece for disposing each mounting electrode. When the crystal resonator element is downsized, it is difficult to dispose the two mounting electrodes on the same end side in the short direction of the crystal resonator element. On the other hand, in the present embodiment, since the mounting electrodes are arranged in a physique, it is easy to arrange the mounting electrodes, which is advantageous for downsizing the resonator element. In the present embodiment, the portion of the fixing portion 14 that connects to the deformable portion 15 is disposed in a direction perpendicular to the deformable portion 15, but is formed with an angle with respect to the deformable portion 15. May be arranged on the same line.

(Embodiment 4)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 6 is a view showing a modification of the crystal resonator of FIG. 1, and is a view as seen from above with the lid 2 and the crystal resonator element 3 removed from the crystal resonator of FIG. However, the arrangement of the crystal vibrating piece 3 is indicated by a dotted line. In addition, description is abbreviate | omitted about the structure similar to each embodiment.

  In the present embodiment, the deformable portion 15 is disposed on a line connecting the connection electrode 36 and the connection electrode 37, and the stress applied to the crystal vibrating piece can be reduced by the expansion and contraction of the deformable portion 15. Here, at least a part of the adhering portion 14 is disposed between the lower surface of the quartz crystal vibrating piece and the upper surface of the cage. Therefore, it is possible to reduce the size of the crystal unit.

(Embodiment 5)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 7 is a view showing a modification of the crystal resonator of FIG. 2, and is a cross-sectional view taken along the line AA ′ of FIG. In addition, description is abbreviate | omitted about the structure similar to each embodiment.

  The crystal resonator element includes a mounting electrode 34 and a mounting electrode that are disposed at both ends of one side of the crystal diaphragm 31 in the lateral direction so as to electrically connect the upper surface and the lower surface via the side surface of the crystal diaphragm 31. 35. The mounting electrode 34 is directly connected to the deformable portion 15. On the other hand, the mounting electrode 35 is electrically connected and fixed via the base electrode 16 and the connection electrode 37.

  In FIG. 7, the fixing portion 14 is arranged on a line connecting the connection electrode 36 and the connection electrode 37, but it may be perpendicular to the line. Further, the adhering portion 14 may be disposed between the lower surface of the crystal vibrating piece and the upper surface of the cage. In any case, stress relaxation applied to the quartz crystal resonator element can be expected as described above.

  Now, a method for directly connecting the mounting electrode 34 and the deformable portion 15 will be described. Examples of the direct connection method include a method using solid phase diffusion of Au—Sn, surface activation bonding between metals, plasma bonding, and the like. By reducing the height of the connection electrode 37, the thickness of the cage can be reduced. Therefore, the crystal unit can be miniaturized.

  FIG. 8 shows a modification of this embodiment. As a modification, not only the mounting electrode 34 and the base electrode 13 are directly connected, but also the mounting electrode 35 and the base electrode 16 are directly connected.

  In this case, the lower surface of the fixing portion 14 and the upper surface of the holding container bottom portion 17 are fixed. On the other hand, the lower surface of the deformable portion 15 is not coupled to the upper surface of the holding container bottom portion 17 and is not fixed. That is, also in this case, the first gap is provided between the upper surface side of the holding container bottom 17 in the deformable portion 15 and the upper surface of the holding container bottom 17. Therefore, the deformable portion 15 is free from the upper surface of the holding container bottom portion 17 and has a structure that can move freely.

  The method of forming the deformed portion 15 of the base electrode 13 is not particularly different from other examples. For example, in the first embodiment, when the resist is formed, the deformed portion 15 can be formed as shown in FIG. 8 by changing the resist thickness to the submicron order. Moreover, the adhering portion 14 can be formed as a laminated structure of an adhesion layer with the upper surface of the holding container bottom portion 17 and Au, and the deformable portion 15 can be formed as an Au single layer. In this case, the deformable portion 15 is not connected to the upper surface of the holding container bottom portion 17 because an adhesion layer with the upper surface of the holding container bottom portion 17 is not provided.

  As a result, the crystal resonator can be lowered in height, and the crystal resonator element can be further reduced in size. In addition, since the base electrode 13 and the base electrode 16 have substantially the same height, and the fixing portion between the base electrode 15 and the mounting electrode 35 is widened, the crystal vibrating piece is less likely to shake due to external vibration, and vibration The characteristics are stable.

(Embodiment 6)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 9 is a view showing a modification of the crystal unit shown in FIG. 1, and is a view as seen from above with the lid 2 removed from the crystal unit shown in FIG. In addition, description is abbreviate | omitted about the structure similar to each embodiment.

  In the present embodiment, the support portion is electrically insulated from the two mounting electrodes of the crystal vibrating piece, and the other base electrode is located between the upper surface of the cage and the lower surface of the crystal vibrating piece and can be deformed. A second deformation portion to be formed, and a second fixing portion that is fixed to the upper surface of the cage, and the second deformation portion is provided between the upper surface side of the cage of the second deformation portion and the upper surface of the cage. 2 voids.

  The holding container has a holding container bottom 17 surrounded by the sealing portion 11, and one base electrode 13 (one base electrode) and the other base electrode 16 (the other base electrode) are arranged on the holding container bottom 17. It is arranged. Similarly to the first embodiment, the base electrode 13 includes a fixing portion 24 (first fixing portion) fixed to the upper surface of the holding container bottom portion 17 and a deformed portion 25 (first fixing portion) separated from the upper surface of the holding container bottom portion 17. 1 deformation part). Further, in the present embodiment, the base electrode 16 has a fixed portion 26 (second fixed portion) fixed to the upper surface of the holding container bottom portion 17 and the deformation separated from the holding container bottom portion 17 like the base electrode 13. It consists of the part 27 (2nd deformation | transformation part).

  The mounting electrode 34 and the deforming portion 25 are disposed so as to overlap each other, and the mounting electrode 35 and the deforming portion 27 are disposed so as to overlap each other substantially at the center of the water holding container bottom 17.

  Further, the crystal diaphragm 31 is fixed to the holding container bottom 17 by a support portion 40. The support portion 40 is disposed on the vertical bisector connecting the mounting electrode 34 and the mounting electrode 35, near the short side facing the short side where the mounting electrode 34 of the crystal resonator element is disposed. . That is, the support portion 40 is on the center line of the crystal vibrating piece 3. Further, the support portion 40 is disposed on an exposed portion of the lower surface of the quartz crystal plate 31 that is different from the electrode film composed of the excitation electrode 32, the mounting electrode 34, and the mounting electrode 35. Moreover, the support part 40 is electrically separated from each electrode. Note that the support portion 40 is preferably located at the same distance from both mounting electrodes. As a result, the symmetry of the crystal vibrating piece is improved, so that the frequency difference between the main vibration and the sub-vibration can be increased and the vibration intensity of the main vibration can be increased. Moreover, since it is mechanically uniform, a long-term structural change occurs in the same manner, and the influence on the vibration is not biased. As a result, vibration characteristics are maintained well in the long term.

  FIG. 10 shows the connection relationship between the crystal vibrating piece 3 and each electrode of the holding container 1. FIG. 10 is a cross-sectional view taken along the line A-A ′ of FIG. 9.

  The external electrode 19 is connected to a fixing portion 24 disposed on the upper surface of the holding container bottom 17 through a through electrode 21 that penetrates the holding container bottom 17. Furthermore, the adhering portion 24 is connected to a deformable portion 25 that can be deformed by having a first gap with the holding container bottom portion 17.

  The external electrode 20 is connected to a fixing portion 26 disposed on the upper surface of the holding container bottom 17 through a through electrode (not shown) that penetrates the holding container bottom 17. Further, the fixing portion 26 is connected to a deformable portion 27 that can be deformed by having a second gap between the fixing portion 26 and the holding container bottom portion 17. That is, the base electrode 16 is positioned between the upper surface of the holding container bottom 17 and the lower surface of the crystal vibrating piece 3, and a deformable portion 27 formed so as to be deformable, and a fixing portion 26 that is fixed to the upper surface of the holding container bottom 17. And a second gap is provided between the upper surface side of the holding container bottom 17 of the deformable portion 27 and the upper surface of the holding container bottom 17.

  The mounting electrode 34 is electrically connected and fixed via the deformable portion 25 and the connection electrode 37. The mounting electrode 35 is electrically connected and fixed to the deformed portion 27 via the connection electrode 37. The manufacturing method of the base electrode 16 is the same as the manufacturing method of the base electrode 13.

  FIG. 11 shows a state in which the crystal vibrating piece 3 is supported and fixed to the holding container 1 via a support portion. FIG. 11 is a cross-sectional view taken along the line B-B ′ of FIG. 9.

  There is a support portion 40 between the holding container bottom portion 17 and the crystal diaphragm 31, whereby the crystal diaphragm 31 is fixed to the upper surface of the holding container bottom portion 17. Since the material of the support part 40 does not generate gas, it is preferably an inorganic material such as low-melting glass or water glass. In addition, you may form the support part 40 with insulating resin.

  According to the present embodiment, the holding container bottom portion 17, the deformable portion 25, and the deformable portion 26 are not fixed, and can be deformed in a direction to reduce the stress applied to the crystal vibrating piece. Therefore, both end portions of the peripheral portion of the crystal vibrating piece where the mounting electrode 34 and the mounting electrode 35 connected to the respective deformed portions are arranged are free ends. Thereby, there is no bad influence which suppresses vibration intensity in a mounting part.

  On the other hand, since the support portion 40 has the crystal vibrating piece 3 fixed thereto, the influence of vibration intensity suppression is exerted. However, since the support portion 40 is on the center line of the crystal vibrating piece 3, the left and right balance of the crystal vibrating piece is improved. For this reason, it is possible to increase the frequency difference between the main vibration and the sub vibration and increase the vibration intensity of the main vibration. Further, since the whole is mechanically uniform, a long-term structural change occurs in the same manner, and the influence on the vibration is not biased. As a result, vibration characteristics are maintained well in the long term.

  FIG. 12 is a diagram illustrating a modified example of the support portion. As shown in FIG. 12, a support pad 41 is provided on the lower surface of the crystal diaphragm 31, and a fixing pad 42 is provided on the upper surface of the holding container bottom 17. The support pad 41 and the fixing pad 42 are fixed to the support portion 40. Thereby, the crystal vibrating piece 3 is fixed to the holding container 1.

  For example, the support pad 41 and the fixing pad 42 are formed by forming a base layer of Cr, Ni, Ti, Mo, W, or the like as an adhesion layer with the crystal diaphragm 31 and the holding container bottom 17, respectively. The upper layer can be formed as Au, Au—Sn, or solder. The support portion 40 can be formed of Au, Au—Sn, or solder. Therefore, the bonding between the support pad 41 and the support portion 40 and the bonding between the support portion 40 and the fixing pad 42 can be performed at a low temperature by ultrasonic bonding or thermocompression bonding. In particular, when the mounting electrode and the base electrode are fixed by the connection electrode, it is possible to fix the support portion to the quartz diaphragm 31 and the holding container bottom portion 17 at the same time, and it can be manufactured with the same thermal history as the previous structure. . Therefore, vibration deterioration due to the process of forming the support portion may not be assumed. As a result, since the structure is well balanced, the vibration characteristics and mechanical strength can be improved.

(Embodiment 7)
The crystal resonator of this embodiment will be described with reference to FIG. FIG. 13 shows a modification of the crystal resonator of FIG. In addition, description is abbreviate | omitted about the structure similar to each embodiment.

  The base electrode 13 and the base electrode 16 are arranged diagonally at the corners of the holding container bottom 17. Although not shown, the mounting electrode 34 and the mounting electrode 35 are arranged diagonally to the crystal vibrating piece 3 in accordance with the arrangement of the base electrode 13 and the base electrode 16. In order to mount the crystal vibrating piece 3, the connection electrode 36 is fixed to the base electrode 13, and the connection electrode 37 is fixed to the base electrode 16.

  The support portions 40 are provided at different corners on the upper surface of the holding container bottom portion 17 where the base electrode 13 and the base electrode 16 are not disposed.

  In the present embodiment, since the connection electrode 36 and the connection electrode 37 are mechanically uniform, long-term structural changes occur evenly, and there is no bias in the influence on vibration. As a result, vibration characteristics are maintained well in the long term. Further, in the diagonal arrangement of the mounting electrodes, the distance between the connection electrode 36 and the connection electrode 37 becomes long, but both electrodes can be relieved of stress because they are connected to the deformed portion. Note that the diagonal arrangement increases the distance between the mounting electrodes, which is advantageous for downsizing the resonator element as in the third embodiment.

  In addition, this invention is not limited to each embodiment, The quartz crystal vibrating piece which has a quartz-crystal vibrating plate and two mounting electrodes provided in the peripheral part vicinity of a quartz-crystal vibrating plate, The holder | retainer which mounts a quartz-crystal vibrating piece, In the quartz vibrator including two base electrodes that are formed on the upper surface of the cage and electrically connected to the two mounting electrodes, respectively, a support portion that is formed on the upper surface of the cage and supports the crystal vibrating piece is provided. One base electrode is positioned between the upper surface of the cage and the lower surface of the quartz crystal vibrating piece facing the upper surface of the cage, and is formed to be deformable, It is sufficient that the first fixing portion is fixed to the upper surface, and the first gap is provided between the upper surface side of the cage in the first deformable portion and the upper surface of the cage. For example, the deformed portion is formed of metal and may not be formed of a thin film.

  In mounting the crystal resonator element on the cage, if the deformed part is mechanically connected without forming the support part, the deformed part may be greatly deformed. When the vibrator is viewed, it is arranged on the lower surface of the quartz crystal resonator piece, and the base electrode and the mounting electrode are connected. Any manufacturing process may be used, such as forming a void after connection and forming a deformed portion. In the case of the above process, in the conventional electrical connection method using wire bonding, wire bonding is performed after the crystal vibrating piece is fixed to the cage, so stress is concentrated on the fixed portion during connection, leading to a decrease in connection strength. However, according to the present invention, the connection strength can be kept high. Therefore, reliability can be maintained high. Further, the holding container does not need to have a holding container side wall portion, and may be configured in a plate shape. In this case, a side wall part can be formed separately or a part of lid can be constituted as a side wall part. Further, the base electrode is not necessarily in contact with the holding container side wall.

DESCRIPTION OF SYMBOLS 1 Holding container 2 Lid 3 Crystal vibrating piece 11 Sealing part 12 Base electrode 13 Base electrode 14 Adhering part 15 Deformation part 16 Base electrode 17 Holding container bottom part 18 Holding container side wall 19 External electrode 20 External electrode 21 Through electrode 22 External electrode 24 Adhering Part 25 Deformation part 26 Adhering part 27 Deformation part 31 Quartz diaphragm 32 Excitation electrode 33 Mounting electrode 34 Mounting electrode 35 Mounting electrode 36 Connection electrode 37 Connection electrode 40 Support part 41 Support pad 42 Fixing pad

Claims (6)

A quartz crystal vibrating plate having a quartz crystal vibrating plate and two mounting electrodes provided in the vicinity of the peripheral edge of the quartz crystal vibrating plate, a holder for mounting the quartz crystal vibrating piece, and formed on the upper surface of the holder, Two base electrodes electrically connected to each of the two mounting electrodes,
In the crystal unit consisting of
Formed on the upper surface of the cage, and has a support part for supporting the quartz crystal vibrating piece,
One of the base electrodes is located between the upper surface of the cage and the lower surface of the crystal vibrating piece facing the upper surface of the cage, and is formed to be deformable, and the holding A first fixing portion fixed to the upper surface of the vessel,
A quartz resonator having a first gap between an upper surface side of the retainer and an upper surface of the retainer in the first deformable portion.   The crystal resonator according to claim 1, wherein the first deformable portion is formed of a thin film.   3. The crystal resonator according to claim 1, wherein the first gap is on a line connecting the first fixing portion and the support portion.   The crystal unit according to claim 1, wherein the support portion is a connection electrode that connects one mounting electrode and the other base electrode.   2. The crystal resonator according to claim 1, wherein the first fixing portion is disposed between a lower surface of the crystal vibrating piece and an upper surface of the cage. The support is electrically insulated from the two mounting electrodes;
The other base electrode is located between the upper surface of the cage and the lower surface of the quartz crystal vibrating piece, and a second deformable portion formed to be deformable, and a second fixed to the upper surface of the cage. A fixing portion;
4. The crystal vibration according to claim 1, wherein a second gap is provided between an upper surface side of the cage of the second deformable portion and an upper surface of the cage. Child.

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