JP2008271331A - Manufacturing method of piezoelectric vibrator, piezoelectric vibrating element, piezoelectric vibrator and oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a piezoelectric vibrator capable of surely chucking and holding (picking up) a compact piezoelectric vibrating element. <P>SOLUTION: First, the piezoelectric vibrating element formed with an electrode, by using a ferromagnetic body material on a surface of a piezoelectric vibrating piece made of a piezoelectric material is manufactured. Next, the electromagnet of a probe is turned on, the electrode of the manufactured piezoelectric vibrating element is chucked and held by its magnetic force, and the electrode is transferred to a base body. Then, the electromagnet is turned off, chucking and holding by the probe are released, and the probe is separated from the piezoelectric vibrating element. Thereafter, the base body is covered with a lid body and a space where the piezoelectric vibrating element is disposed is airtightly sealed, thereby manufacturing the piezoelectric vibrator. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention belongs to the technical field of the structure of a piezoelectric vibration element and a method of manufacturing a piezoelectric vibrator using this element.

  An example of a conventional crystal unit will be described with reference to a cross-sectional view of FIG. Reference numeral 10 in FIG. 9 denotes a package, in which a crystal vibration element 12 having electrodes 11a and 11b formed on both main surfaces is stored. The package 10 is composed of a ceramic case body 13 having an upper surface opened and a metal lid body 14. The case body 13 and the lid body 14 are seam welded via a sealing material (not shown), and the inside thereof is in a vacuum state. In the crystal vibration element 12, an electrode 11 b formed on one surface side of the crystal vibration element 12 in a lateral orientation extending into the space inside the package 10 is formed on the surface of the pedestal 17 by the conductive adhesive 16. The conductive paths 18 and 19 (18 is a conductive path on the back side of the drawing) are fixed.

  The oscillating operation of the crystal resonator thus configured is performed through the external terminals 20, 21, the conductive paths 18, 19 and the conductive adhesive 16 provided on both side surfaces of the case body 13, and the crystal oscillating element 12. This occurs when a voltage is applied to the electrodes 11a and 11b formed on both main surfaces.

  A method for manufacturing the above-described crystal resonator will be briefly described. First, a quartz wafer is prepared in which quartz vibrating elements 12 having electrodes 11a and 11b formed on both main surfaces are continuously arranged in a matrix. Subsequently, the quartz wafer is cut and divided by dicing or the like along the outline of the quartz vibrating element 12 to be singulated. The separated crystal vibrating elements 12 are picked up by a suction nozzle and arranged one by one in a plurality of recesses formed on the surface of the ceramic substrate.

  Briefly describing the pickup operation of the suction nozzle, as shown in FIG. 10, the suction nozzle 22 sucks the crystal vibrating element 12 to the tip surface of the suction nozzle 22 by suction through the hole 24. It is like that. Further, by stopping suction by the suction pump 23 in this state, the crystal vibrating element 12 sucked on the tip surface of the suction nozzle 22 is released.

  After placing the crystal vibration element 12 in all the concave portions formed on the surface of the ceramic substrate by the suction nozzle 22, a metal substrate having the same shape as the ceramic substrate is bonded through a sealing material. The sealing material portion is heated to melt the sealing material, and the metal substrate is fixed to the surface of the ceramic substrate. Thereafter, the laminated body is cut by dicing or the like along the partition lines formed in the laminated body, whereby the crystal resonator shown in FIG. 9 is completed.

However, there are the following problems in the manufacturing method of the crystal unit described above. In recent years, with the miniaturization of the crystal resonator, the miniaturization of the crystal vibrating element 12 has been advanced. Specifically, the size is as extremely small as 2 mm ² or less. For this reason, when the suction nozzle 22 sucks the target crystal vibration element 12, the crystal vibration element 12 around the target crystal vibration element 12 may be sucked. 22 also needs to be reduced in size in accordance with the small crystal vibrating element 12. However, if the suction nozzle 22 is made smaller, the inner diameter of the suction hole formed in the tip surface of the suction nozzle 22 is also reduced accordingly, so that there is a possibility that a sufficient suction force cannot be secured.

  On the other hand, in Patent Document 1, a ferromagnetic material is formed on the surface of a crystal resonator, and the inner wall surface of a cap that accommodates the crystal resonator is opposed to the ferromagnetic material formed on the surface of the crystal resonator. Although it is described that a permanent magnet is attached to the quartz magnet to prevent deformation of the quartz crystal due to gravity due to the attraction force of the permanent magnet, this technique holds and holds a small quartz vibrating element as described above. It is not intended for.

JP 54-65497 (FIG. 3)

  The present invention has been made in view of such circumstances, and an object of the present invention is to be used in a method for manufacturing a piezoelectric vibrator capable of reliably attracting and holding (pickup) a small piezoelectric vibration element, and the manufacturing method. An object of the present invention is to provide a piezoelectric vibration element, a piezoelectric vibrator and an oscillator manufactured by the manufacturing method.

The present invention includes a step of manufacturing a piezoelectric vibration element in which an electrode using a ferromagnetic material is formed on the surface of a piezoelectric vibration piece made of a piezoelectric material;
The electrode of the manufactured piezoelectric vibration element is attracted and held by the magnetic force of the electromagnet of the probe, and transferred to the base body;
Next, turning off the electromagnet to release the adsorption holding by the probe, and separating the probe from the piezoelectric vibration element;
Then, covering the base body with a lid body and hermetically sealing a space in which the piezoelectric vibration element is disposed is included.
In the above-described method for manufacturing a piezoelectric vibrator, it is preferable that a large number of piezoelectric vibration elements transferred by the probe are divided on the wafer. Moreover, it is preferable that the surface of the electromagnet of the probe is coated with a resin in order to prevent the electromagnet from directly contacting the electrode of the piezoelectric vibration element.

  The piezoelectric vibrating element of the present invention includes a piezoelectric vibrating piece made of a piezoelectric material, an electrode formed on the surface of the piezoelectric vibrating piece and using a ferromagnetic material to be picked up by the magnetic force during assembly, It is provided with. In this piezoelectric vibration element, it is preferable that the electrode includes a laminate in which a gold layer is laminated on a ferromagnetic material layer, and the surface of the gold layer is exposed.

The piezoelectric vibrator according to the present invention includes a base body that supports the above-described piezoelectric vibration element, a lid that covers the base body and uses an arrangement space for the piezoelectric vibration element as an airtight space, An external electrode provided outside and means for electrically connecting the external electrode and the excitation electrode of the piezoelectric vibration element are provided.
An oscillator according to the present invention includes the above-described piezoelectric vibrator and an oscillation circuit that oscillates the piezoelectric vibrator.

  According to the present invention, since a piezoelectric vibration element in which an electrode using a ferromagnetic material is formed on the surface of a piezoelectric vibrating piece made of a piezoelectric material is used, suction holding (pickup) can be performed using a suction nozzle. The small quartz crystal vibrating element that could not be obtained can be reliably attracted and held by the magnetic force of the probe. Accordingly, it is very convenient to transfer a small crystal vibrating element in the manufacture of the crystal resonator.

An embodiment of a crystal resonator which is a piezoelectric resonator according to the present invention will be described. FIG. 1 is a cross-sectional view of a crystal resonator according to the present invention. In the crystal unit shown in FIG. 1, the same parts as those described with reference to FIG. 9 in the section of the prior art are denoted by the same reference numerals, and the description thereof is omitted. As shown in FIG. 1, a plate-shaped crystal vibrating piece 30 having a size of 2 mm ² or less and 1.5 mm ^{2 in} this example is stored in the package 10. As shown in FIG. 2, ferromagnetic materials 31a and 31b such as nickel (Ni), titanium (Ti), cobalt (Co), and the like are formed on both main surfaces of the crystal vibrating piece 30, and Gold (Au) films 32a and 32b are formed on the surfaces of the magnetic materials 31a and 31b. The ferromagnetic materials 31 a and 31 b and the Au films 32 a and 32 b are used as electrodes 33 a and 33 b that excite the quartz crystal vibrating piece 30.

  As described above, the ferromagnetic materials 31a and 31b and the Au films 32a and 32b are laminated in this order on the surface of the crystal vibrating piece 30 to form the electrodes 33a and 33b, thereby forming the electrodes 33a and 33b from the crystal vibrating piece 30. Prevents peeling. That is, since the Au films 32a and 32b have low adhesion to the crystal vibrating piece 30, the ferromagnetic materials 31a and 31b are formed between the crystal vibrating piece 30 and the Au films 32a and 32b. The film thickness of the ferromagnetic material 31 needs to be such that the quartz crystal vibrating element 3 can be attracted and held (pick up) by a probe that generates a magnetic field, which will be described later, specifically 200 mm or more.

  The crystal vibrating element 3 in which the electrodes 33a and 33b made of the ferromagnetic materials 31a and 31b and the Au films 32a and 32b are formed on the surface of the crystal vibrating piece 30 is in a lateral orientation extending into the space inside the package 10. The electrode 33 formed on the one surface side of the crystal vibrating element 3 is fixed to the conductive paths 18 and 19 (18 is a conductive path on the back side of the paper surface) formed on the surface of the base 17 by the conductive adhesive 16. Has been. The oscillating operation of the crystal resonator configured in this way is performed through the external terminals 20, 21, the conductive paths 18, 19 and the conductive adhesive 16 provided on both side surfaces of the case body 13, and the crystal vibrating element 3. This occurs when a voltage is applied to the electrodes 33a and 33b formed on both main surfaces.

  Before describing the method of manufacturing the above-described crystal resonator, an example of a probe used in the manufacturing method described later will be described with reference to FIGS. FIG. 3 is a schematic cross-sectional view showing the configuration of the probe 4. 3 in FIG. 3 is a cylindrical metal body having a diameter of 0.4 mm. For example, a copper wire 42 having a diameter of 0.2 mm is spirally provided around the metal body 40. A power supply unit 44 is provided on the upstream side of the copper wire 42 via a switch unit 43, and a magnetic field is generated at the tip 41 of the metal body 40 by flowing a current from the power supply unit 44 to the copper wire 42. It has become. That is, the probe 4 is constituted by a solenoid type electromagnet in this example.

  The operation of the probe 4 will be described. As shown in FIG. 4A, the tip portion 41 of the probe 4 is brought into contact with the surface of the crystal vibration element 3 with the switch portion 43 turned off. Subsequently, as shown in FIG. 4B, the switch portion 43 is turned on to generate a magnetic field at the tip portion 41 of the probe 4, and the ferromagnetic material 31a formed on the surface of the crystal vibration element 3 by this magnetic field. , 31b are attracted, and the small crystal vibrating element 3 is attracted to the distal end surface of the probe 4. Further, by turning off the switch portion 43 in this state, the small crystal vibrating element 3 adsorbed on the distal end surface of the probe 4 is released. Further, as shown in FIG. 3, a resin film 48 is formed on the surface of the tip portion 41 of the metal body 40 in order to prevent the surface of the crystal vibration element 3 from being damaged when attracted by the probe 4. Yes.

  Next, a method for manufacturing the above-described crystal resonator will be described with reference to FIGS. First, as shown in FIG. 5, a crystal wafer 50 is prepared in which crystal vibration elements 3 having electrodes 3a and 3b formed on both main surfaces are arranged in a matrix. Here, a method for manufacturing the quartz wafer 50 will be briefly described. First, a device wafer is prepared, and crystal vibrating pieces are formed in a matrix on the wafer by etching or the like. Next, an electrode film 33 having a ferromagnetic material 31 as a lower layer and an Au film 32 as an upper layer is formed on both main surfaces of each crystal vibrating piece 30. Subsequently, as shown in FIG. 5, the crystal wafer 50 placed on the placement table 53 is cut and divided along the outline of the crystal vibration element 3 by dicing or the like to be singulated.

  Next, as shown in FIG. 5, the support portion 45 that supports the probe 4 is lowered to a predetermined height position by the drive mechanism 46 that drives the probe 4 in the vertical direction, and the switch portion 43 is turned off as shown in FIG. In this state, the tip portion 41 of the probe 4 is brought into contact with the surface of the crystal vibration element 3 that has been separated. Subsequently, as shown in FIG. 4B, the switch portion 43 is turned on to generate a magnetic field at the tip portion 41 of the probe 4, and the separated crystal vibrating element 3 is attracted to the tip surface of the probe 4 by its magnetic force. Let Thereafter, as shown in FIG. 5, the support portion 45 is raised to a predetermined height position by the drive mechanism 46, and a plurality of concave portions 52 are formed on the surface by the drive mechanism 47 that drives the support portion 45 in the horizontal direction. The substrate is moved to the manufactured substrate 51. As shown in FIG. 5, the substrate 51 is placed on a placing table 54.

  Then, the support portion 45 is lowered to a predetermined height position by the drive mechanism 46, and the crystal vibrating element 3 enters the recess 52. Thereafter, the switch portion 43 is turned off to release the adsorption by the probe 4, and the crystal vibration element 3 is placed in the recess 52 via the conductive adhesive 16. Conductive paths 18 and 19 are formed in the recess 52, and by placing the crystal vibration element 3 in the recess 52, the electrodes 33a and 33b formed on the surface of the crystal vibration element 3 and The conductive paths 18 and 19 formed in the recess 52 are electrically connected via the conductive adhesive 16.

  After the quartz-crystal vibrating element 3 is placed as described above in all the recesses 52 formed on the surface of the ceramic substrate 51 by the probe 4, the same shape as the ceramic substrate 51 is obtained as shown in FIG. The metal substrate 60 thus bonded is bonded through a seal material (not shown), and the seal material portion is heated to melt the seal material, thereby fixing the metal substrate 60 to the surface of the ceramic substrate 51. Then, as shown in FIG. 7, the surface of the metal substrate 60 is covered with a dicing tape 70, and cut along the dicing line 71 with a dicing saw (not shown) from above the dicing tape 70, so that the ceramic substrate 51 is removed. Crystal units are cut one by one. Then, by providing the external terminals 20 and 21 on both side surfaces of the cut crystal unit, the crystal unit shown in FIG. 1 is completed.

  According to the above-described embodiment, as shown in FIG. 2, the piezoelectric vibrating element 3 in which the ferromagnetic materials 31a and 31b are formed on the surface of the crystal vibrating piece 30 is used. As shown in FIG. 4, a small crystal vibrating element that could not be sucked and held (pick up) using the suction nozzle can be reliably sucked and held by the magnetic force of the probe 4. Therefore, as described with reference to FIGS. 5 to 7, it is possible to transfer the small crystal vibrating element 3 in the manufacture of the crystal resonator, which is very convenient.

  In addition, as shown in FIG. 2, the quartz-crystal vibrating element 3 of the above-described embodiment is formed by laminating ferromagnetic materials 31a and 31b and Au films 32a and 32b in this order on both main surfaces of the quartz-crystal vibrating piece 30. Although this laminated film is configured as electrodes 33a and 33b, only the ferromagnetic materials 31a and 31b are formed on both main surfaces of the quartz crystal vibrating piece 30, and the ferromagnetic materials 31a and 31b are configured as electrodes 33a and 33b. May be. In addition, an electrode film 33 in which the ferromagnetic material 31 and the Au film 32 are laminated in this order or an electrode film 33 made of only the ferromagnetic material 31 is formed on one side of the crystal vibrating piece 30 to constitute the crystal vibrating element 3. May be. Even with such a configuration, the magnetic force of the probe 4 can surely attract and hold.

Further, the crystal resonator shown in FIG. 1 is mounted on a wiring substrate 81 on which circuit components of the oscillation circuit 80 are mounted as shown in FIG.
Further, when a small SAW element is transferred in the manufacture of a SAW (Surface Acoustic Wave) device, the small SAW element may be transferred using the probe 4 described above. In this case, a ferromagnetic material is used as an electrode constituting the SAW element.

1 is a schematic longitudinal sectional view showing a crystal resonator according to an embodiment of the present invention. It is a schematic longitudinal cross-sectional view which shows the element for crystal vibrations accommodated in the said crystal oscillator. It is a schematic sectional drawing which shows the structure of the front-end | tip part of a probe. It is explanatory drawing explaining operation | movement of the said probe. It is a schematic perspective view which shows the manufacturing method of the crystal oscillator based on embodiment of this invention. It is a schematic perspective view which shows a mode that a ceramic board | substrate and a metal board | substrate are piled up. It is a schematic plan view which shows a mode that the board | substrate made from a ceramic is cut | divided into one crystal oscillator one by one. It is the schematic which shows the crystal oscillator which concerns on embodiment of this invention. It is a schematic longitudinal cross-sectional view which shows the conventional crystal oscillator. It is explanatory drawing explaining the structure of a suction nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Package 13 Case body 14 Cover body 3 Crystal vibration element 30 Crystal vibration piece 31a, 31b Ferromagnetic material 32a, 32b Au film | membrane 33a, 33b Electrode 4 Probe 40 Metal body 41 Tip part 42 Copper wire 43 Switch part 44 Power supply part 45 Support portions 46 and 47 Drive mechanism 50 Crystal wafer 51 Ceramic substrate 52 Recesses 53 and 54 Mounting table 60 Metal substrate 70 Dicing tape 71 Dicing line 8 Crystal oscillator 80 Oscillation circuit 81 Wiring substrate

Claims (7)

Manufacturing a piezoelectric vibration element in which an electrode using a ferromagnetic material is formed on the surface of a piezoelectric vibration piece made of a piezoelectric material;
A step of attracting and holding the electrode of the manufactured piezoelectric vibration element by the magnetic force of the electromagnet of the probe and transferring it to the base body;
Next, turning off the electromagnet to release the adsorption holding by the probe, and separating the probe from the piezoelectric vibration element;
And a step of airtightly sealing a space in which the piezoelectric vibration element is disposed by covering the base body with a lid body.   2. The method of manufacturing a piezoelectric vibrator according to claim 1, wherein the piezoelectric vibration element transferred by the probe is in a state of being divided into a large number on the wafer.   3. The piezoelectric vibrator according to claim 1, wherein the surface of the electromagnet of the probe is coated with a resin in order to prevent the electromagnet from directly contacting the electrode of the piezoelectric vibration element. Production method. A piezoelectric vibrating piece made of a piezoelectric material;
An element for piezoelectric vibration, comprising: an electrode formed on the surface of the piezoelectric vibrating piece and made of a ferromagnetic material so as to be picked up by the magnetic force at the time of assembly.   The piezoelectric vibration element according to claim 4, wherein the electrode includes a laminate in which a gold layer is laminated on a ferromagnetic material layer, and a surface of the gold layer is exposed. A base body supporting the piezoelectric vibration element according to claim 4;
A lid that covers the top of the base body and uses the arrangement space of the piezoelectric vibration element as an airtight space;
An external electrode provided outside the base body;
A piezoelectric vibrator comprising: means for electrically connecting the external electrode and the excitation electrode of the piezoelectric vibration element.   An oscillator comprising the piezoelectric vibrator according to claim 6 and an oscillation circuit that oscillates the piezoelectric vibrator.

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