JP2009135749A - Piezoelectric vibrator and piezoelectric oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate manufacture without receiving influence of a size of a piezoelectric vibration element. <P>SOLUTION: In this piezoelectric vibrator 100, a mount pad 14 provided inside a recessed part 13 formed in one main surface of a container 10 formed into a rectangular with a plane view and a lead pattern 23 connected to an exciting electrode 22 provided in a piezoelectric vibration element 20 are connected to each other with a conductive adhesive material D, and the recessed part 13 of the container 10 is air-tightly sealed with a lid body 30 formed into a rectangular with a plane view. The lead pattern 23 provided in the piezoelectric vibration element 20 is formed in only both the main surfaces of the piezoelectric vibration element 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a piezoelectric vibrator and a piezoelectric oscillator used in electronic equipment.

  Conventionally, as a surface-mountable piezoelectric vibrator used for electronic equipment, for example, a crystal vibrator has been used. This crystal resonator has been proposed to be hermetically sealed with a lid made of an insulating material or a metal material in a state where the crystal vibrating element is mounted on a container made of an insulating material having a recess (for example, Patent Document 1).

In a conventionally used crystal resonator, the structure of a crystal resonator element is provided at one end of a crystal plate to energize the crystal plate, excitation electrodes provided on both main surfaces thereof, and these excitation electrodes. And a routing pattern to be formed.
These routing patterns are provided in pairs, and one routing pattern is connected to an excitation electrode provided on one main surface, and one corner at one end of the crystal plate. Has been routed to the department. The other routing pattern is connected to an excitation electrode provided on the other main surface, and is routed to another corner at one end of the crystal plate.
Since each of the routing patterns is routed so as to face both main surfaces of the crystal plate at the corner, it is also provided on the side surface of the crystal plate.

  When manufacturing such a crystal resonator element, first, the shape of the excitation electrode and the lead pattern are formed on the crystal wafer, using a technique such as photolithography, on the crystal plate as a plurality of crystal resonator elements. At this time, a metal film is formed on the quartz wafer by electrolytic plating, electroless plating, sputtering, vapor deposition, etc. on the quartz wafer, and the excitation electrode and the lead pattern are arranged in accordance with the position of the quartz plate in the outer shape. Apply resist to Thereafter, etching is performed to remove the exposed metal film, and then the resist is removed to form excitation electrodes and routing patterns on both main surfaces of the quartz wafer. After separating each crystal plate into individual pieces, a mask is applied to the crystal plate, and a metal film is formed on the side surface of the crystal plate, which is a part of the drawing pattern, by vapor deposition or sputtering, thereby completing the drawing pattern.

As described above, conventionally used crystal resonator elements tend to be miniaturized as electronic devices are miniaturized. For example, the crystal unit container has a length of 2.0 mm and a width of 1. mm. If it is 6 mm in size, it must be manufactured in a smaller size.
Therefore, the smaller the container size, the smaller the size of the quartz crystal vibration element must be manufactured. The same applies to, for example, a piezoelectric oscillator having a structure in which two concave portions are provided in one container body. For example, in the case where two recesses are formed on the same plane of the container body, or in the case of a piezoelectric oscillator in which recesses are formed on both main surfaces, miniaturization is progressing. The vibration element is also required to be downsized.

JP2007-067795

However, since the excitation electrodes provided on the crystal plate become smaller as the crystal resonator element and the crystal resonator element used in the crystal oscillator become smaller, it is necessary to form a part of the drawing pattern on the side surface of the crystal plate. It is conceivable that accuracy must be increased and workability is deteriorated. As a result, there are concerns that frequent failures and deterioration in yield will occur.
For example, since it is necessary to refill the container body with a jig made of a holder having a mask provided with a predetermined pattern, productivity is deteriorated.
In addition, since the quartz plate is small, handling is poor, and it has become difficult to form a part of the pattern on the side surface of the quartz plate.

  Therefore, an object of the present invention is to provide a piezoelectric vibrator and a piezoelectric oscillator that solve the above-described problems and can be easily manufactured without being affected by the size of the piezoelectric vibration element.

  In order to solve the above-described problems, the present invention provides a piezoelectric vibration in which a mounting pad provided in a container body and a routing pattern connected to an excitation electrode of the piezoelectric vibration element are joined, and the container body is hermetically sealed with a lid. The lead pattern of the piezoelectric vibration element is formed only on both main surfaces of the piezoelectric vibration element.

  Further, according to the present invention, the piezoelectric vibrator includes a conductive adhesive that joins the mounting pad and the routing pattern, and the conductive adhesive has a routing pattern facing the lid side of the piezoelectric vibration element. The mounting pad and the routing pattern are electrically and mechanically joined so as to come into contact with each other.

  Further, the present invention is a piezoelectric oscillator in which two recesses are provided in one container body, a piezoelectric vibration element is mounted in one recess, and an electronic component including an oscillation circuit is mounted in the other recess, The lead pattern of the piezoelectric vibration element is formed only on both main surfaces of the piezoelectric vibration element, and the lead pattern is connected to the mounting pad provided in the one concave portion of the container body and the excitation electrode of the piezoelectric vibration element. And are configured to be joined together.

  Further, according to the present invention, the piezoelectric oscillator includes a conductive adhesive that joins the mounting pad and the routing pattern, and the conductive adhesive contacts the routing pattern facing the lid side of the piezoelectric vibration element. Thus, the mounting pad and the routing pattern are electrically and mechanically joined.

According to such a piezoelectric vibrator, since it is not necessary to provide a part of the drawing pattern on the side surface of the piezoelectric vibrator, it is possible to easily manufacture the piezoelectric vibrator.
In addition, according to such a piezoelectric oscillator, it is not necessary to provide a part of the drawing pattern on the side surface of the piezoelectric vibration element, so that the piezoelectric oscillator can be easily manufactured.

  Next, the best mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail with reference to the drawings as appropriate. The piezoelectric vibration element will be described as a crystal vibration element. Moreover, in each embodiment, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

(First embodiment)
FIG. 1A is a perspective view showing an example of a piezoelectric vibration element used in the piezoelectric vibrator according to the first embodiment of the present invention, and FIG. 1B is a perspective view showing an example of a container body. 2A is a perspective view showing a state in which a conductive adhesive is applied to a mounting pad, FIG. 2B is a perspective view showing a state in which a piezoelectric vibration element is mounted, and FIG. 2C is a view of a piezoelectric vibrator. It is a perspective view which shows an example. FIG. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is a perspective view showing an example of a state in which excitation electrodes and routing patterns are provided on a quartz wafer. FIG. 5 is a partial perspective view showing a state in which a conductive adhesive is applied to a mounting pad provided in a portion that becomes a container body of a wafer. FIG. 6 is a perspective view showing a state in which a crystal resonator element is mounted. FIG. 7 is a partial perspective view showing an example of a state in which a wafer on which a portion to be a container is arranged and a wafer to be a lid are joined.

  As shown in FIGS. 1 to 3, the piezoelectric vibrator 100 according to the first embodiment of the present invention includes a container body 10, a crystal vibrating element 20 that is a piezoelectric vibrating element, a lid 30, and a conductive adhesive D. Consists mainly of.

The container body 10 is made of, for example, glass or crystal, and has a rectangular shape in plan view and has a concave portion 13 on one main surface as shown in FIG. 1B, and the crystal resonator element 20 is placed in the concave portion 13. Two mounting pads 14 for mounting are provided in pairs.
Specifically, when the surface of the container body 10 where the concave portion 13 is not provided is the bottom and the surface where the concave portion 13 is opened is the top, the bottom surface of the concave portion 13 is, for example, along the short side of the four corners. Two mounting pads 14 are formed on each of two adjacent corners to form a pair.

The mounting pad 14 is made of a metal film, and is electrically connected to an external terminal G provided on the lower surface 12 of the container body 10 through the inside of the container body 10. Note that the two mounting pads 14 are not electrically connected to each other.
Further, a metallized layer (not shown) is provided on the main surface 11 where the recess 13 of the container body 10 is formed, and a sealing material (not shown) for the lid body 30 (see FIG. 2C). And can be joined.

The lid 30 is made of, for example, glass or quartz, and serves to hermetically seal the concave portion 13 provided in the container body 10 as shown in FIGS. 2 (c) and 3. After 20 is mounted, it is joined to the container body 10. The lid body 30 has a quadrangular shape in plan view and is made of a metal material.
A sealing material (not shown) is provided on one main surface of the lid 30 and is joined to a metallized layer (not shown) provided on the container body 10.
It should be noted that the container 10 and the lid 30 may be bonded to each other depending on the material of the sealing material (not shown), but the sealing material such as seam welding, laser irradiation, or heat bonding with a halogen lamp may be used. Corresponding joining methods can be used.

As shown in FIGS. 1A and 3, the crystal resonator element 20 includes a crystal plate 21, an excitation electrode 22, and a routing pattern 23.
The quartz plate 21 has, for example, an AT-cut square shape in plan view, and excitation electrodes 22 are provided at predetermined positions on both main surfaces of the quartz plate 21. The excitation electrodes 22 are provided so as to face each other.

As shown in FIG. 1A, FIG. 2B, and FIG. 3, one routing pattern 23 is provided for each excitation electrode 22. The routing pattern 23 is provided so as to reach from the excitation electrode 22 to one corner 23A on one end side of the crystal plate 21, and is also provided at the corner 23B on the back side thereof, and the corners 23A, 23B. It is in a state opposite to each other. However, the crystal plate 21 is also not provided with the routing pattern 23 on the side surface.
Therefore, the routing pattern 23 used with the same polarity is not electrically connected between the portion provided on one main surface side of the quartz plate 21 and the portion provided on the other main surface. As will be described later, these are electrically connected when mounted on the container body 10 using the conductive adhesive D.

  Further, in the routing pattern 23 used in the same polarity, a portion provided on one main surface side of the crystal plate 21 and a portion provided on the other main surface are opposed to each other at the corners 23A and 23B. The two routing patterns 23 are provided so as to reach different corners. Thereby, when it joins to the container body 10 using the conductive adhesive D mentioned later, joining strength can be maintained similarly to the past.

Such a crystal resonator element 20 is manufactured by the following processes, for example.
A metal film forming process is performed in which a metal film is formed on both main surfaces of the quartz wafer by electrolytic plating, electroless plating, sputtering, and vapor deposition.
Next, a resist coating process is performed in which a resist is applied to the positions where the excitation electrode 22 and the lead pattern 23 correspond to the outer shape of the crystal plate 21.
In this state, etching is performed to perform a metal film removing process for removing the exposed metal film not covered with the resist.
The remaining resist is removed to expose the metal film (see FIG. 4), and a resist removing process is performed for the excitation electrode 22 and the lead pattern 23.
In this state, the crystal resonator element 20 is obtained by being separated into individual crystal plates 21.
As can be seen from this process, the process of providing a part of the pattern 23 on the side surface of the quartz plate 21 is not necessary.

  In addition, a metal mask (not shown) having a penetrating portion having the same shape as the excitation electrode 22 and the lead pattern 23 is superposed on the quartz wafer, and then a metal film is formed in the penetrating portion by vapor deposition, sputtering, or the like. Then, the step of providing the excitation electrode 22 and the routing pattern 23 may be performed by peeling off the overlapped metal mask.

  As shown in FIGS. 2B, 5 and 6, the conductive adhesive D electrically and mechanically connects the mounting pad 14 of the container body 10 and the lead pattern 23 on the corner side of the crystal resonator element 20. Used when mechanically joining. The conductive adhesive D adheres to the lead pattern 23 provided on both principal surfaces of the crystal plate 21 of the crystal resonator element 20 while adhering to the mounting pad 14 of the container body 10, thereby crystal vibration. The state where the element 20 is bonded to the mounting pad 14 is maintained.

The relationship of bonding between the conductive adhesive D and the crystal resonator element 20 will be described. Specifically, as shown in FIG. 3, the lead pattern 23 of the crystal resonator element 20 facing the bottom surface side of the recess 13 of the container body 10 and the mounting pad 14 of the container body 10 are joined by the conductive adhesive D. However, the conductive adhesive D is also attached to the routing pattern 23 of the crystal resonator element 20 facing the opening side of the container body 10.
Thereby, the routing pattern 23 of the crystal resonator element 20 facing the bottom surface side of the recess 13 of the container body 10 plays a role of maintaining the bonding strength.

In addition, as shown in FIG. 5, the conductive adhesive D is applied in the state of the wafer before the container body 10 is singulated, and in this state, as shown in FIG. It may be mounted on the body 10. Thereafter, as shown in FIG. 7, the wafer on which the lid 30 is arranged is bonded to the wafer on which the crystal resonator element 20 is mounted to obtain a wafer on which the piezoelectric vibrator 100 is arranged. This wafer is cut into pieces by dicing or the like to obtain individual piezoelectric vibrators 100.
In this case, a wafer made of glass in which the container body 10 is arranged and a wafer made of glass in which the lid body 30 is arranged may be joined by direct bonding, or made of crystal in which the container body 10 is arranged. The wafer and the wafer made of crystal on which the lid 30 is arranged may be bonded by direct bonding.

Thereby, since it is not necessary to provide a part of the drawing pattern 23 on the side surface of the crystal resonator element 20, the piezoelectric vibrator 100 can be easily manufactured.
In other words, the function as the piezoelectric vibrator 100 can be maintained without providing the lead pattern 23 to the side surface of the crystal plate 21 of the crystal resonator element 20. In addition, since a part of the routing pattern 23 is not provided on the side surface of the quartz plate 21, high precision and complicated work such as masking, vapor deposition, and sputtering are eliminated, and workability is improved even if the quartz resonator element 20 is downsized. Can be improved.

(Modification of the first embodiment)
Although not shown, such a piezoelectric vibrator 100 may be a piezoelectric oscillator bonded to a container on which an integrated circuit element including an oscillation circuit is mounted, or an integrated circuit including an oscillation circuit using a lead frame. A piezoelectric oscillator in which elements are joined and the outer shape is adjusted with a mold resin may be used.

(Second embodiment)
FIG. 8A is a perspective view showing an example of a container body used in the piezoelectric oscillator according to the second embodiment of the present invention, and FIG. 8B is a diagram in which a piezoelectric vibration element and an integrated circuit element are mounted on the container body. It is a perspective view which shows a state, (c) is a perspective view which shows the piezoelectric oscillator which concerns on 2nd embodiment of this invention.

  As shown in FIG. 8, the piezoelectric oscillator 200 according to the second embodiment of the present invention is mounted in a container body 10A having at least two recesses 13A and 13B on the main surface and one recess 13A. It is mainly composed of a crystal resonator element 20 that is a piezoelectric resonator element, a lid 30 that hermetically seals these recesses 13A and 13B, and an integrated circuit element 40 that includes an oscillation circuit mounted in the other recess 13B. Yes.

The container body 10A used in the piezoelectric oscillator 200 according to the second embodiment of the present invention is, for example, in the same plane, provided with two recesses 13A and 13B on one main surface, and the other main body. An external terminal (not shown) is provided on the surface.
Of the two recesses 13A and 13B, one recess 13A is provided with a mounting pad 14A for mounting the crystal resonator element 20, and the other recess 13B is mounted with an integrated circuit element 40 having an oscillation circuit. An IC pad 14B is provided. The mounting pad 14A is electrically connected to a predetermined portion of the IC pad 14B. A predetermined portion of the IC pad 14B is connected to a predetermined external terminal so that a voltage can be applied from a mounting board (not shown).

  Also in such a container body 10A, a crystal resonator element 20 similar to the piezoelectric resonator element 20 used in the piezoelectric vibrator 100 according to the first embodiment is used. As described above, the lead pattern 23 of the crystal resonator element 20 is formed only on both main surfaces of the crystal resonator element 20 and is not provided on the side surface. In this crystal resonator element 20, a mounting pad 14 </ b> A provided in one recess 13 </ b> A of the container body 10 </ b> A and a lead pattern 23 connected to the excitation electrode 22 of the crystal resonator element 20 are joined by a conductive adhesive D. Use.

Thereby, since it is not necessary to provide a part of the drawing pattern 23 on the side surface of the crystal resonator element 20, the piezoelectric oscillator 200 can be easily manufactured.
In other words, the function as the piezoelectric oscillator 200 can be maintained without providing the lead pattern 23 to the side surface of the crystal plate 21 of the crystal resonator element 20. In addition, since a part of the routing pattern 23 is not provided on the side surface of the quartz plate 21, high-precision and complicated work such as masking, vapor deposition, and sputtering is eliminated, and workability is improved even if the quartz resonator element 20 is downsized. Can be improved.

(Modification of the second embodiment)
Although not shown, such a piezoelectric oscillator 200 can also be applied to an oscillator having a structure in which the side surface of the concave portion provided in the container body is formed in a step shape. For example, an integrated circuit element including an oscillation circuit may be mounted at the lowest position in the recess, and a crystal vibration element may be mounted on the stepped portion of the stepped side surface. That is, it is possible to use a container having a structure having a recess in the recess.

(Third embodiment)
FIG. 9 is a cross-sectional view showing an example of a piezoelectric oscillator according to the third embodiment of the present invention.
As shown in FIG. 9, the piezoelectric oscillator 201 according to the third embodiment of the present invention includes a container body 10 </ b> B having recesses 13 </ b> C and 13 </ b> D provided on both main surfaces, and a piezoelectric vibration mounted in one recess 13 </ b> C. It is mainly composed of a crystal resonator element 20 that is an element, a lid 30 that hermetically seals the recess 13C, and an integrated circuit element 40 that includes an oscillation circuit mounted in the other recess 13D.

  Also in such a container body 10B, a crystal resonator element 20 similar to the piezoelectric resonator element 20 used in the piezoelectric vibrator 100 according to the first embodiment is used. As described above, the lead pattern 23 of the crystal resonator element 20 is formed only on both main surfaces of the crystal resonator element 20 and is not provided on the side surface. In this crystal resonator element 20, a mounting pad 14 </ b> C provided in one recess 13 </ b> C of the container body 10 </ b> B and a lead pattern 23 connected to the excitation electrode 22 of the crystal resonator element 20 are joined by a conductive adhesive D. Use.

Thereby, since it is not necessary to provide a part of the drawing pattern 23 on the side surface of the crystal resonator element 20, the piezoelectric oscillator 201 can be easily manufactured.
In other words, the function as the piezoelectric oscillator 201 can be maintained without providing the lead pattern 23 to the side surface of the crystal plate 21 of the crystal resonator element 20. In addition, since a part of the routing pattern 23 is not provided on the side surface of the quartz plate 21, high-precision and complicated work such as masking, vapor deposition, and sputtering is eliminated, and workability is improved even if the quartz resonator element 20 is downsized. Can be improved.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. For example, a piezoelectric material such as ceramic can be used as the piezoelectric vibration element. In addition, the piezoelectric vibration element may have a tuning fork shape, a shape in which a portion to be excited and vibrated is recessed or a shape in which the thickness is increased, and the edge portion is beveled or a plano convex It may have a shape that has undergone processing or biconvex processing.
For joining the container body and the lid body, a joining method other than the above-described method can be used. For example, when the material of the container body and the lid body is the same material, when glass is used as an example, the container body and the lid body may be joined by direct joining, or either the container body or the lid body Alternatively, a bonding film made of aluminum may be provided and bonded by anodic bonding.
The excitation electrode and the routing pattern may be a metal film, and a conventionally known metal material can be used. For example, a structure in which Ti, Cr, or the like is used for the base and Au or the like is provided on the base may be used.
Furthermore, a piezoelectric vibrator or a piezoelectric oscillator having a structure in which a piezoelectric vibration element is mounted on a flat substrate and hermetically sealed with a lid having a recess may be used.

(A) is a perspective view which shows an example of the piezoelectric vibration element used for the piezoelectric vibrator which concerns on 1st embodiment of this invention, (b) is a perspective view which shows an example of a container body. (A) is a perspective view which shows the state which apply | coated the electrically conductive adhesive to the mounting pad, (b) is a perspective view which shows the state which mounted the piezoelectric vibration element, (c) is an example of a piezoelectric vibrator. It is a perspective view shown. It is AA sectional drawing of FIG.2 (c). It is a perspective view which shows an example of the state which provided the excitation electrode and the routing pattern in the quartz wafer. It is a fragmentary perspective view which shows the state which apply | coated the electrically conductive adhesive to the mounting pad provided in the part used as the container body of a wafer. It is a perspective view which shows the state which mounted the crystal vibration element. It is a fragmentary perspective view which shows an example of the state which joined the wafer in which the part used as a container body was arranged, and the wafer used as a cover body. (A) is a perspective view which shows an example of the container body used for the piezoelectric oscillator which concerns on 2nd embodiment of this invention, (b) is the state which mounted the piezoelectric vibration element and the integrated circuit element in the container body. (C) is a perspective view showing a piezoelectric oscillator according to a second embodiment of the present invention. It is sectional drawing which shows an example of the piezoelectric oscillator which concerns on 3rd embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Piezoelectric vibrator 200, 201 Piezoelectric oscillator 10, 10A, 10B Container body 13, 13A, 13B, 13C, 13D Recessed part 14, 14A, 14C Mounting pad 14B, 14D IC pad 20 Crystal vibrating element (piezoelectric vibrating element)
DESCRIPTION OF SYMBOLS 21 Quartz plate 22 Excitation electrode 23 Leading pattern 30 Lid 40 Integrated circuit element D Conductive adhesive material

Claims (4)

A piezoelectric vibrator in which a mounting pad provided in a container body and a lead pattern connected to an excitation electrode of a piezoelectric vibration element are joined, and the container body is hermetically sealed with a lid,
The lead pattern of the piezoelectric vibration element is
A piezoelectric vibrator, wherein the piezoelectric vibrator is formed only on both main surfaces of the piezoelectric vibration element. A conductive adhesive for joining the mounting pad and the routing pattern;
The conductive adhesive is
2. The piezoelectric vibrator according to claim 1, wherein the mounting pad and the lead pattern are electrically and mechanically joined so as to contact a lead pattern facing the lid side of the piezoelectric vibration element. A piezoelectric oscillator in which two recesses are provided in one container body, a piezoelectric vibration element is mounted in one recess, and an electronic component including an oscillation circuit is mounted in the other recess,
The lead pattern of the piezoelectric vibration element is formed only on both main surfaces of the piezoelectric vibration element,
A piezoelectric oscillator comprising: a mounting pad provided in the one concave portion of the container body and a routing pattern connected to an excitation electrode of the piezoelectric vibration element. A conductive adhesive for joining the mounting pad and the routing pattern;
The conductive adhesive is
4. The piezoelectric oscillator according to claim 3, wherein the mounting pad and the routing pattern are electrically and mechanically joined so as to contact the routing pattern facing the lid side of the piezoelectric vibration element.

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