JP2003188677A - Piezoelectric device, its manufacturing method, portable telephone utilizing the piezoelectric device and electronic equipment utilizing the piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a joining structure of a piezoelectric oscillation piece and an electrode in a package excellent in impact resistance and improve adhesion force therein. <P>SOLUTION: A piezoelectric device stores the piezoelectric oscillation piece 32 in an inside space S of the package 36, and joins electrodes 31 and 31 provided in the inside of the package and extraction electrodes 71 and 71 of the piezoelectric oscillation piece by a silicone-based conductive adhesive, so that it fixes a part of the piezoelectric oscillation piece. The extraction electrode has a base layer 73 provided on the surface side of a material constituting the piezoelectric oscillation piece, and a surface noble metal layer 72 by noble metal provided on the surface side of the base layer. The base layer 73 is partially exposed on the surface noble metal layer 72 opposed to at least a package side electrode of the extraction electrode. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a piezoelectric device having a piezoelectric vibrating piece incorporated in a package.

[0002]

2. Description of the Related Art In recent years, devices such as HDDs (hard disk drives), mobile computers, and small information devices such as IC cards, and mobile communication devices such as mobile phones, car phones, and paging systems are small and thin. The piezoelectric devices used in these devices are required to be small and thin. At the same time, there is a demand for a surface-mounting type piezoelectric device that can be surface-mounted on the circuit board of the apparatus. 16 and 17
FIG. 16 is a schematic diagram showing a configuration example of such a piezoelectric device, and FIG. 16 is a schematic plan view showing the configuration of the piezoelectric device,
FIG. 17 is a schematic cross-sectional view of the piezoelectric device of FIG. 16 taken along the line AA.

In FIGS. 16 and 17, a conventional piezoelectric device 1 contains a piezoelectric vibrating reed 2 inside a package 6. The piezoelectric vibrating piece 2 is formed by using, for example, a quartz substrate. The piezoelectric vibrating reed 2 is formed in a tuning fork type having a base portion 11 joined to the electrode portion of the package 6 and a pair of vibrating arms 4 and 5 extending in parallel from the base portion 11. A metal electrode is formed.

The package 6 is formed by laminating two sheets 12 and 13 made of ceramic so as to form a predetermined internal space S inside, and is entirely formed in a rectangular shape.
In this internal space S, the lead-out electrodes 12, 12 of the base 11 of the piezoelectric vibrating piece 2 are bonded to the electrode parts 3, 3 on the inner bottom of the package 6 via a conductive adhesive 7 or the like. It is fixed. Then, the extraction electrode 12,
Reference numeral 12 is formed integrally and continuously with the above-mentioned driving metal electrode (not shown). The tip of the piezoelectric vibrating piece 2 is a free end. At the open upper end of the package 6, through a brazing material 8 such as low melting point glass,
The lid body 9 made of glass is joined to be sealed.

The piezoelectric device 1 is configured as described above, and a driving voltage from the outside is transmitted through the electrode portion 3, the conductive adhesive 7 and the extraction electrodes 12 and 12 to the piezoelectric vibrating piece 2.
Be transmitted to. As a result, the voltage from the excitation electrode (not shown) of the piezoelectric vibrating piece 2 is transmitted to the piezoelectric material, so that the pair of vibrating arms 4 and 5 generate bending vibration and vibrate at a predetermined frequency. By extracting this vibration frequency to the outside, an output of a predetermined frequency can be obtained.

[0006]

By the way, in such a piezoelectric device 1, the extraction electrode 1 of the piezoelectric vibrating reed 2 is formed.
Silicone-based conductive adhesives are used as the conductive adhesives 7 and 7 used for joining the electrodes 2 and 12 and the package-side electrode portions 3 and 3. This silicone-based conductive adhesive is configured to have conductivity by containing a conductive material such as silver particles in a silicone-based resin. Further, the silicone-based conductive adhesive has a higher ability to absorb impact force than the epoxy-based adhesive or the polyimide-based adhesive, and therefore exhibits a performance of being strong against a drop impact or the like. be able to.

However, the extraction electrodes 12, 12 of the piezoelectric vibrating reed 2 shown in FIG. 18A have chromium (C) as an underlayer, as shown in the structure of the lower surface of FIG. 18B.
r) Gold (Au) coating portions 14 and 14 are provided on the lower surfaces of 13 and 13. Therefore, the silicone-based conductive adhesives 7, 7 need to be bonded to the gold coating portions 14, 14. However, the gold-coated portions 14 and 14 have a slower curing reaction at the adhesive interface with the silicone-based conductive adhesive 7 and 7 than other portions, so that it is difficult to control the dry state in the bonding process. Therefore, there is a problem that the adhesive strength is insufficient.

Therefore, the silicone type conductive adhesive 7,
Instead of exposing the gold on the bonding surface with 7,
As shown in (a), a base layer 13 is formed on the front surface side of the piezoelectric vibrating piece 2, a gold coating portion 14 is provided on the front surface side, and a chromium film 15 is formed on the front surface side of the gold coating portion 14. There are possible ways to do this. Or, more simply, FIG.
As shown in (b), the chromium film 1 is formed on the surface of the piezoelectric vibrating piece 2.
A method of forming 5 is conceivable.

However, the silicone-based conductive adhesive 7,
If the gluing surface with 7 is a chrome surface as described above, the wettability of the adhesive is too good, causing slipping on the gluing surface,
It is difficult to correctly position the piezoelectric vibrating piece 2 and it is difficult to stably bond the piezoelectric vibrating piece 2.

The object of the present invention is to solve the above-mentioned problems, and in the bonding structure of the piezoelectric vibrating reed and the electrode in the package, the shock resistance is excellent and the adhesive force is improved. Piezoelectric device that can
It is an object of the present invention to provide a manufacturing method thereof, a mobile phone device and an electronic device using the piezoelectric device.

[0011]

The above-mentioned object is defined in claim 1.
According to the invention, the piezoelectric vibrating piece is housed in the internal space of the package, and the electrode provided inside the package and the lead-out electrode of the piezoelectric vibrating piece are joined by a silicone-based conductive adhesive, A piezoelectric device configured to fix a part of the piezoelectric vibrating piece, wherein the extraction electrode is provided on a surface side of a material forming the piezoelectric vibrating piece and a surface layer of the underlying layer. And a surface noble metal layer made of a noble metal, wherein the underlying layer is partially exposed in the surface noble metal layer facing at least the electrode on the package side of the extraction electrode. To be done. According to the configuration of claim 1,
At least the surface noble metal layer of the lead-out electrode of the piezoelectric vibrating piece, which faces at least the electrode on the package side, exposes the underlayer partially not on the entire surface. As a result, in the region where the underlayer is exposed, the wettability with respect to the conductive adhesive is improved, and therefore the adhesive force is stronger. That is, by using a silicone-based conductive adhesive as the conductive adhesive, the piezoelectric device of the present invention can have a bonding structure with excellent impact resistance and improved adhesive strength.

According to a second aspect of the present invention, in the structure of the first aspect, the material layer of the piezoelectric vibrating piece is partially exposed in the surface noble metal layer, instead of the base layer. To do. According to the configuration of claim 2, the material layer of the piezoelectric vibrating piece is partially exposed, not the entire surface, in the surface noble metal layer facing at least the electrode on the package side of the extraction electrode of the piezoelectric vibrating piece. . As a result, in the area where the material layer of the piezoelectric vibrating piece is exposed, the wettability with respect to the conductive adhesive is improved, and therefore the adhesive force is stronger.

According to a third aspect of the present invention, in the structure of the first or second aspect, the underlayer or the material layer of the piezoelectric vibrating piece partially exposed to the surface noble metal layer,
The surface noble metal layer is formed in a regular geometric shape. According to the configuration of claim 3,
It is easy to form a regular geometric pattern on the photomask used in the process of forming the extraction electrode. Further, the area ratio of each region of the base layer or the material layer of the piezoelectric vibrating piece can be easily set correctly so as to be a required ratio. Moreover, it is possible to easily determine whether or not the alignment of the quartz substrate and the photomask is correctly performed in forming the extraction electrode, only by evaluating the appearance of the geometrical shape of the formed extraction electrode.

According to a fourth aspect of the present invention, in the structure according to any one of the first to third aspects, the material layer of the piezoelectric vibrating reed is quartz and the underlayer is chromium (Cr) or a chromium alloy. And According to the structure of claim 4, when quartz is selected as the material layer of the piezoelectric vibrating piece, it is suitable for forming chromium, which is selected as the base layer. When the crystal or chrome is partially exposed on the surface of the extraction electrode, a high adhesive strength can be exhibited by using a silicone-based conductive adhesive.

According to a fifth aspect of the present invention, in the structure according to any one of the first to fourth aspects, the material layer of the piezoelectric vibrating piece is quartz, and the surface noble metal layer is gold (Au) or a gold alloy. Characterize. According to the configuration of claim 5, when quartz is selected as the material layer of the piezoelectric vibrating piece and gold (Au) or a gold alloy is selected as the surface noble metal layer, the piezoelectric vibrating piece having good aging characteristics can be obtained. . When the surface noble metal layer is gold (Au) or a gold alloy,
By partially exposing the chromium or material layer in the surface noble metal layer, an effect of improving the bonding force can be expected especially when a silicone-based conductive adhesive is used.

Further, the above-mentioned object is, according to the invention of claim 6, the step of accommodating the piezoelectric vibrating piece in the internal space of the package, and joining the electrode provided inside the package and the piezoelectric vibrating piece. A method of manufacturing a piezoelectric device including:
The extraction electrode of the piezoelectric vibrating piece forms an underlayer on the surface side of the material layer of the piezoelectric vibrating piece, then forms a surface noble metal layer on the surface side of this underlayer, and further forms the surface noble metal layer partially. Of the extraction electrode is formed so that the underlying layer is partially exposed at least on the surface of the extraction electrode facing the electrode on the package side. A conductive adhesive of silicone type is applied between the electrode surface on the side of the lead electrode and the surface of the lead-out electrode where the underlying layer is partially exposed, so that the electrode on the package side and the piezoelectric vibration are applied. This is achieved by a method for manufacturing a piezoelectric device, in which a lead electrode of one piece is joined. According to the structure of claim 6, by using the process according to this method, it is possible to easily expose the underlayer to the surface noble metal layer partially. Further, as a result, regarding the area where the underlayer is exposed,
The wettability is improved with respect to the conductive adhesive, and thus the adhesive force can be improved.

According to a seventh aspect of the present invention, in the structure of the sixth aspect, the material of the piezoelectric vibrating piece is partially formed on the surface of the lead electrode facing at least the electrode on the package side, instead of the base layer. It is characterized in that the layer is exposed. According to the configuration of claim 7, by using the process according to this method, the material layer of the piezoelectric vibrating piece can be partially exposed to the surface noble metal layer easily.

According to an eighth aspect of the present invention, in the structure of the sixth or seventh aspect, the underlayer or the material layer of the piezoelectric vibrating piece partially exposed to the surface noble metal layer,
The surface noble metal layer is formed in a regular geometric shape.

According to a ninth aspect of the present invention, in the structure according to any of the sixth to eighth aspects, the material layer of the piezoelectric vibrating piece is quartz and the underlayer is chromium (Cr) or a chromium alloy. And

According to a tenth aspect of the present invention, in the structure of any of the sixth to ninth aspects, the material layer of the piezoelectric vibrating piece is quartz, and the surface noble metal layer is gold (Au) or a gold alloy. The method for manufacturing a piezoelectric device according to claim 6, which is characterized in that:

According to the invention of claim 11, the above object is to accommodate the piezoelectric vibrating piece in the internal space of the package,
A piezoelectric device was used in which an electrode provided inside the package and a lead-out electrode of the piezoelectric vibrating piece were joined by a silicone-based conductive adhesive to fix a part of the piezoelectric vibrating piece. In the mobile phone device, the extraction electrode has a base layer provided on the front surface side of the material forming the piezoelectric vibrating piece, and a surface noble metal layer made of a noble metal provided on the front surface side of the base layer. A piezoelectric device in which the underlying layer is partially exposed, or a material layer of the piezoelectric vibrating piece is partially exposed in the surface noble metal layer facing at least the package-side electrode of the extraction electrode. The piezoelectric device is used to obtain a clock signal for control,
Achieved by mobile phone devices.

Further, according to the invention of claim 12, the above object is to accommodate the piezoelectric vibrating piece in the internal space of the package,
A piezoelectric device was used in which an electrode provided inside the package and a lead-out electrode of the piezoelectric vibrating piece were joined by a silicone-based conductive adhesive to fix a part of the piezoelectric vibrating piece. An electronic device,
The extraction electrode has a base layer provided on the front surface side of the material forming the piezoelectric vibrating piece, and a surface noble metal layer made of a noble metal provided on the front surface side of the base layer, and at least the extraction electrode The surface noble metal layer facing the electrode on the package side is controlled by a piezoelectric device in which the underlying layer is partially exposed or a piezoelectric device in which the material layer of the piezoelectric vibrating piece is partially exposed. It is achieved by an electronic device, characterized in that it is adapted to obtain a clock signal for.

[0023]

1 to 3 show a first embodiment of a piezoelectric device of the present invention. FIG. 1 is a schematic perspective view thereof, FIG. 2 is a schematic plan view thereof, and FIG. C- in FIG.
It is a C line schematic sectional drawing. In these drawings, the piezoelectric device 30 shows an example in which a piezoelectric vibrator is configured, and the piezoelectric device 30 includes a piezoelectric vibrating piece 32 in a package 36.
Are housed. The package 36 is formed in a shallow box shape by, for example, stacking ceramic green sheets of aluminum oxide and then firing them. Each laminated substrate (not shown) is formed with a predetermined hole inside thereof to form a predetermined internal space S inside when laminated.

In the inner space S of the package 36 in the vicinity of the left end in the figure, at the bottom exposed in the inner space S, electrode portions 31, 31 plated with Au and Ni are predetermined as shown in FIG. Are formed at intervals.
The electrode portions 31, 31 are connected to the outside and supply a drive voltage. Conductive adhesives 43 and 43 are applied on the respective electrode portions 31 and 31, and the base portion 51 of the piezoelectric vibrating piece 32 is placed on the conductive adhesives 43 and 43 and conductive adhesive is applied. The agents 43, 43 are bonded by being hardened. As the conductive adhesives 43, 43, in this embodiment, a silicone-based conductive adhesive in which silver particles are contained in a silicone-based resin is used. This silicone-based conductive adhesive has the property of absorbing shock after curing.

The piezoelectric vibrating reed 32 is made of, for example, crystal, and other than crystal, a piezoelectric material such as lithium tantalate or lithium niobate can be used. In the case of the present embodiment, the piezoelectric vibrating piece 32 is divided into two forks parallel to the right side in the drawing with the base 51 fixed to the package 36 side as described later, with the base 51 as the base end. A so-called tuning fork type piezoelectric vibrating reed having a pair of vibrating arms 34 and 35 extending and having a shape like a tuning fork is used. The piezoelectric vibrating reed of the present invention is not limited to such a tuning fork type, but a so-called AT-cut vibrating reed obtained by cutting a piezoelectric material such as crystal into a rectangular shape may be used.

Lead-out electrodes 71, 71 for transmitting a driving voltage are formed at the portions of the base portion 51 of the piezoelectric vibrating piece 32 that come into contact with the conductive adhesives 43, 43.
The driving electrode of the piezoelectric vibrating piece 32 is electrically connected to the electrode portions 31, 31 on the package 36 side via the conductive adhesives 43, 43. The electrode portions 31 and 31 are for applying a drive voltage to the piezoelectric vibrating piece 32 from the outside. That is, on the surface of the piezoelectric vibrating piece 32, a drive electrode or an exciting electrode (not shown) having a complicated pattern necessary for exciting the piezoelectric vibrating piece 32 is formed. Then, as shown in FIG. 3, at the ends in the lengthwise direction of the base portion 51 of the piezoelectric vibrating piece 32 and in the vicinity of both ends in the widthwise direction, as shown in FIG. Lead-out electrodes 71, 71 electrically connected to the electrode portions 31, 31 on the package 36 side are formed in order to transmit a driving voltage to the electrodes.
The detailed structure of the extraction electrodes 71, 71 will be described later.

A lid 39 is joined to the open upper end of the package 36 via a brazing material 33 such as low melting point glass to seal the package 36. The lid 39 is made of a light-transmissive material, such as glass, in order to adjust the frequency with the laser light or the like transmitted through the lid 39.

Further, in this embodiment, the package 36
By forming a hole in the vicinity of the right end portion in FIGS. 2 and 3 of the intermediate substrate (not shown) of the laminated substrate constituting
A recess 42 corresponding to the thickness of this laminated substrate is formed. The recess 42 is located below the free end 32b of the piezoelectric vibrating piece 32. This effectively prevents the free end 32b of the piezoelectric vibrating piece 32 from abutting against the inner bottom surface of the package 36 when the free end 32b of the piezoelectric vibrating piece 32 is swung in the direction of the arrow when an external impact is applied to the package 36. .

FIG. 4A shows a base portion 51 of the piezoelectric vibrating piece 32.
FIG. 4B is an enlarged plan view showing the vicinity, and FIG.
It is a BB line cutting end view of (a). In these drawings, the extraction electrodes 71, 71 actually constitute a part of an electrode (not shown) formed on the surface of the piezoelectric vibrating piece 32 as described above, and the structure thereof is as shown in FIG. Four
As shown in (b), a chromium (Cr) layer 73 as an underlayer is formed on the surface of the crystal material 75 of the piezoelectric vibrating piece 32.
Is equipped with. A gold (Au) coating layer 72 as a noble metal film is provided on the chrome layer 73.

Here, usually, the chromium layer 7 which is an underlayer.
The gold coating layer 72, which is a noble metal layer, is formed on the entire surface on the surface side of No. 3, but in this embodiment, as shown in the figure, the gold coating layer 72 is partially covered by the underlying chromium layer. The layer 73 is exposed. Specifically, as shown in FIG. 4A, the surfaces of the extraction electrodes 71, 71 are
The gold coating layer 72 and the chrome layer 73 are exposed so as to form a regular geometric pattern. In the case of the drawing, in particular, the surfaces of the respective extraction electrodes 71, 71 are formed with the same area.
The gold coating layers 72, 72 and the chromium layers 73, 73 are divided in a diagonal direction to form a square lattice or a grid pattern. As a result, the exposed areas of the gold coating layer 72 and the chromium layer 73 are equal to each other.

The present embodiment is configured as described above, and in the piezoelectric device 30, the extraction electrodes 71, 71 of the piezoelectric vibrating piece 32 partially expose the chromium layers 73, 73. As a result, in the areas where the chrome layers 73, 73 are exposed, the wettability is improved with respect to the conductive adhesives 43, 43 described with reference to FIGS. 2 and 3, and thus the adhesive strength is stronger. . Moreover, the conductive adhesive 43, 43
By using a silicone-based conductive adhesive for the piezoelectric device 30, the piezoelectric device 30 can have a bonding structure with excellent impact resistance and improved adhesive strength.

Here, in FIG. 4, the extraction electrode 7
Although the chrome layers 73 and 73 are partially exposed on both the front surface 71a and the back surface 71b of Nos. 1, 71, the chrome layer 73 may be exposed only on the back surface 71b in FIG. That is, the back surface 7 facing at least the electrode portions 31, 31 on the package 36 side of the extraction electrodes 71, 71, which is a main joint surface with the conductive adhesives 43, 43.
If the exposed portions of the chromium layer 73 are formed only on the portions 1b and 71b, the above-described effects can be obtained. Further, the exposed areas of the gold coating layer 72 and the chrome layer 73 do not necessarily have to be equal to each other, as long as the chrome layer 73 is partially exposed. Furthermore, the desired effect can be obtained by dividing the number of regions of the gold coating layer 72 and the chromium layer 73 into at least four in one extraction electrode 71. The gold coating layer 72 as the noble metal layer may be made of gold alloy, silver, or silver alloy, for example. The chromium layer 73 as the underlayer may be a chromium alloy, nickel or a nickel alloy.

FIG. 5 shows a first modification of this embodiment. In this first modified example, only the structure of the extraction electrode is different from the above-mentioned extraction electrodes 71, 71, and the other structures are the same, so the duplicated description will be omitted and only the differences will be described. Extraction electrode 8 of piezoelectric vibrating piece 32 of FIG.
1, 81 have the same chrome and gold as the layer structure, but differ only in the shape in which the gold coating layer 72 and the chrome layer 73 are exposed. That is, the extraction electrode 81,
On the surface of 81, the gold coating layer 72 and the chrome layer 73 are exposed so as to have a regular geometric pattern.
Compared with the case of (a), it has a finer square grid pattern or a grid pattern. Therefore, also in the case of this first modified example, the extraction electrode 71,
It is possible to exhibit the same operational effect as the joint structure using 71.

6 and 7 are process drawings showing a method of manufacturing the extraction electrodes 71, 71 of the piezoelectric vibrating piece 32 of the piezoelectric device 30. In FIG. 6A, a chromium layer 73 is formed on the surface of the crystal material 75 forming the piezoelectric vibrating piece 32 by vapor deposition, sputtering or plating.
A gold coating layer 72 is sequentially formed on the surface. Next, FIG.
As shown in FIG. 6B, a resist 76 is applied to the surface of the gold coating layer 72, and as shown in FIG.
A mask 77 corresponding to the outer shape of No. 2 (see FIG. 2) is arranged and exposed. In this case, the mask 77 has an opening for separating the above-mentioned extraction electrodes 71, 71, as shown in the drawing.

Next, as shown in FIG. 6 (d), the exposed resist 76 is removed, and subsequently, as shown in FIG. 6 (e), the gold coating layer corresponding to the region of the peeled resist 76 is removed. The 72 and the chromium layer 73 are removed by using an etching solution. Next, as shown in FIG. 7F, the mask 77 and the resist 76 are removed, and as shown in FIG. 7G, a resist 78 is applied again on the entire surface.

Then, as shown in FIG. 7H, a mask 79 is prepared. The mask 79 is, for example, as shown in FIG.
It is shaped so as to cover the portions of the gold coating layers 72, 72 shown in FIG. Therefore, when the extraction electrodes 71, 71 are formed by a photolithography method, if the gold coating layer 72 and the chrome layer 73 are exposed so that the surface thereof has a regular geometric pattern, It is easy to precisely form the mask 79 used in.

Next, as shown in FIG. 7 (i), the mask 7
The resist 78 not hidden by 9 is exposed and removed. Then, the exposed gold coating layer 72 is removed with a corresponding etching solution, and the remaining resist is peeled off as shown in FIG. 7 (j). As described above, the extraction electrode 7 described in FIG. 4 is formed by the process using photolithography.
1, 71 can be formed. As described above, by performing the manufacturing process of FIGS. 6 and 7, the chromium layer 73 can be easily partially exposed on the surfaces of the extraction electrodes 71, 71 of the piezoelectric vibrating piece 32. Further, as a result, the wettability of the region where the chrome layer 73 is exposed with respect to the conductive adhesive 43 is improved, and thus the adhesive force can be improved.

FIG. 8A shows a second modification of the piezoelectric device 30 according to the first embodiment. This second
In the modified example, only the configuration of the extraction electrode is different from the extraction electrodes 71, 71 described in FIG. 4, and the other configurations are the same, so duplicate description will be omitted and only the differences will be described. Extraction electrodes 82, 82 of the piezoelectric vibrating piece 32 of FIG.
Is the same as the chromium and gold that make up the layer structure,
The only difference is the shape in which the gold coating layer 72 and the chromium layer 73 are exposed. That is, the surfaces of the extraction electrodes 82, 82 are formed so that the gold coating layer 7 has a regular geometric pattern.
2 and the chrome layer 73 are exposed. For example, the gold coating layer 72 has a square shape and the other gold coating layer 72a has a triangular shape, and the gold coating layer has two different shapes. The triangular gold coating layer 72a has its apex
The patterns are arranged so as to be located side by side on both side edges of each extraction electrode 82, 82. Therefore, also in the case of the second modification, it is possible to exhibit the same function and effect as the joining structure using the extraction electrodes 71, 71 of FIG.

FIG. 8B shows a process of forming the extraction electrodes 82, 82 having the structure of FIG.
The drawing shows a case where the extraction electrodes 82, 82 are not formed correctly due to the displacement of the mask. The extraction electrodes 82, 82 having the structure of FIG. 8A are also formed by the same manufacturing process as described in FIGS. 6 and 7, and for example,
The arrangement position of the mask described in FIG. 7H is shown in FIG.
The finished state is shown when there is a slight deviation in the directions of arrows B and C.

According to FIG. 8 (b), it can be seen that due to the displacement in the direction of arrow B, the vertical positions of the square gold coating layer 72 and the chromium layer 73 are displaced. Further, it is observed that the apex of the triangular gold coating layer 72a is cut off at the side edge of the left extraction electrode 82 due to the displacement in the arrow C direction. in this way,
Since the chromium layer 73 and the gold coating layers 72 and 72a are formed in a regular geometric shape, the areas occupied by the regions of the chromium layer 73 and the gold coating layer 72 are formed by the required area. And the extraction electrode 82,
82 It can be utilized to easily determine whether or not the formation process has been performed correctly by simply evaluating the appearance of the formed geometric shape. Further, as a method for making a simple determination, for example, the size itself of the triangular gold coating layer 72a is determined as a range of product tolerance, and when the gold coating layer 72a disappears at the end of the extraction electrode 82. May be provided with a criterion of being defective.

FIG. 9 shows a third modification of the piezoelectric device 30 according to the first embodiment. In the third modified example, only the structure of the extraction electrode is different from the extraction electrodes 71, 71 described in FIG. 4, and the other configurations are the same, and thus the duplicate description will be omitted and only the differences will be described. explain. The extraction electrodes 83, 83 of the piezoelectric vibrating piece 32 of FIG.
Chromium and gold constituting the layered structure are the same, but the only difference is the shape in which the gold coating layer 72 and the chromium layer 73 are exposed. That is, the surfaces of the extraction electrodes 83, 83 have a gold coating layer 72 so that they have a regular geometric pattern.
And the chrome layer 73 are exposed. For example, the gold coating layer 7
2 has a square shape, and the other gold coating layer 72b has a large rotated square shape, and the gold coating layer has two different shapes. The apex of the rotated large square gold coating layer 72b has the extraction electrodes 83, 8
It is designed to be located on both side edges of No. 3 and arranged side by side. Therefore, also in the case of the third modification, it is possible to determine whether or not the extraction electrodes 83, 83 have been correctly formed by the same method as in FIG. 8B.

FIG. 10 shows a fourth modification of the piezoelectric device 30 according to the first embodiment. In the fourth modified example, only the structure of the extraction electrode is different from the extraction electrodes 71, 71 described in FIG. 4, and the other structures are the same, and thus the duplicate description will be omitted and only the differences will be described. explain. Extraction electrodes 84, 84 of the piezoelectric vibrating piece 32 of FIG.
Is the same as the chromium and gold that make up the layer structure,
The only difference is the shape in which the gold coating layer 72 and the chromium layer 73 are exposed. That is, the surfaces of the extraction electrodes 84, 84 are formed so that the gold coating layer 7 has a regular geometric pattern.
2 and the chrome layer 73 are exposed. For example, the gold coating layer 72 has a square shape, and the other gold coating layers 72c have the following shapes.
The shape is such that the vertices of small triangles are butted against each other, and the gold coating layer has two different shapes. The gold coating layer 72c having a shape in which the vertices of small triangles are butted against each other is formed so as to be positioned and arranged on both side edges of the extraction electrodes 84, 84. Therefore, also in the case of the fourth modification, it is possible to determine whether or not the extraction electrodes 84, 84 are correctly formed, by the same method as in FIG. 8B.

FIG. 11A shows the first piezoelectric device 30.
5 shows a fifth modification example of the embodiment of FIG. In the fifth modification, only the structure of the extraction electrode is different from that of the extraction electrodes 84, 84 described with reference to FIG. 10, and the other structure is the same. Therefore, duplicate description will be omitted and only the differences will be described. explain. That is, the surfaces of the extraction electrodes 85, 85 have a gold coating layer 72 so that they have a regular geometric pattern.
And the chrome layer 73 are exposed. For example, the gold coating layer 7
The shape of 2 is a square, and the shape of the other gold coating layer 72c is such that the vertices of small triangles are butted against each other, and the gold coating layer has two different shapes. The gold coating layer 72c having a shape in which the vertices of small triangles are butted against each other is formed not only on both side edges of the extraction electrodes 85, 85 but also on the lower edge in the drawing. There is.

FIG. 11B shows a case where the extraction electrodes 85 and 85 are not formed correctly due to a mask shift in the process of forming the extraction electrodes 85 and 85 having the structure of FIG. 11A. ing. As can be understood from FIG. 11B, the shape of the gold coating layer 72c disposed on the side edge of the left extraction electrode 85 and the right extraction electrode 8
Since the shape of the gold coating layer 72c arranged on the side edge of No. 5 is different, it can be easily discriminated that it is a pattern shift in the direction of arrow C.

FIG. 12 shows a second embodiment of the piezoelectric device of the present invention. FIG. 12A shows the piezoelectric vibrating piece 3.
12 is an enlarged plan view showing the vicinity of the base 51 of FIG.
12B is a sectional view taken along line DD of FIG. 12A.
In these figures, the portions denoted by the same reference numerals as those in FIG. 4 have the same configuration, and therefore, duplicate description will be omitted, and the differences will be mainly described below. The extraction electrodes 21 and 21 actually form a part of an electrode (not shown) formed on the surface of the piezoelectric vibrating piece 32, and the structure thereof is as shown in FIG.
As shown in (b), a chromium (Cr) layer 73 as an underlayer is formed on the surface of the crystal material 75 of the piezoelectric vibrating piece 32.
Is equipped with. A gold (Au) coating layer 72 as a noble metal film is provided on the chrome layer 73.

Here, the chrome layer 7 which is the underlayer is usually used.
The gold coating layer 72, which is a noble metal layer, is formed on the entire surface on the surface side of No. 3, but in this embodiment, as shown in the drawing, the crystal material 75, which is the material layer, is partially exposed. . Specifically, as shown in FIG. 12A, the gold coating layer 72 and the crystal material 75 are exposed so that the surfaces of the extraction electrodes 21 and 21 have a regular geometric pattern. In the case of the drawing, in particular, the surface of each of the extraction electrodes 21 and 21 is divided into four with the same area, and the gold coating layers 72 and 72 and the crystal materials 75 and 75 are arranged in a square lattice shape or in a diagonal direction. It is in the form of a grid. Thereby, the exposed areas of the gold coating layer 72 and the crystal material 75 are equal to each other.

The present embodiment is configured as described above, and in the piezoelectric device 20, the extraction electrodes 21 and 21 of the piezoelectric vibrating piece 32 partially expose the crystal materials 75 and 75. As a result, in the areas where the crystal materials 75, 75 are exposed, the wettability is improved with respect to the conductive adhesives 43, 43 described in FIG. 2 and FIG. 3, and therefore the adhesive force is stronger. . Moreover, the conductive adhesive 43, 43
As in the first embodiment, by using a silicone-based conductive adhesive for the piezoelectric device 20, the piezoelectric device 20 can have a bonding structure with excellent impact resistance and improved adhesive strength. is there.

FIG. 13 is a process diagram showing a method of manufacturing the extraction electrodes 21 and 21 of the piezoelectric vibrating piece 32 of the piezoelectric device 20. In FIG. 13A, the piezoelectric vibrating piece 3
A chromium layer 73 and a gold coating layer 72 are sequentially formed on the surface of the crystal material 75 forming the second layer by vapor deposition, sputtering or plating. Next, FIG.
As shown in (b), a resist 25 is applied to the surface of the gold coating layer 72, and as shown in FIG. 13 (c), a mask 26 corresponding to the outer shape of the piezoelectric vibrating piece 32 (see FIG. 2) is formed. Place and expose. This mask 26 is, for example, as shown in FIG.
It is shaped so as to cover the portions of the gold coating layers 72, 72 shown in FIG. Therefore, when the extraction electrodes 21 and 21 are formed by a photolithography method, if the gold coating layer 72 and the crystal material 75 are exposed so that the surface thereof has a regular geometric pattern, It is easy to precisely form the mask 26 used in.

Next, as shown in FIG. 13D, the resist 25 not hidden by the mask 26 is exposed and removed. Then, the exposed gold coating layer 72 and the chromium layer 73 are removed by a corresponding etching solution, and the state shown in FIG. Then, the resist is peeled off. From the above,
As shown in FIG. 13F, the extraction electrode 2 described in FIG. 12 is formed by a process using photolithography.
1, 21 can be formed. As shown in FIG.
In the manufacturing process of, the extraction electrodes 21, 2 of the piezoelectric vibrating piece 32 are
It is possible to easily partially expose the crystal material 75, which is the material layer, to the surface of 1. Further, as a result, in the area where the crystal material 75 is exposed, the conductive adhesive 43
On the other hand, the wettability is improved, and thus the adhesive force can be improved.

Further, by applying the above manufacturing process, in the second embodiment as well, as in the first embodiment, as shown in FIGS. 8 and 9 to 11, the extraction electrodes 21, By allowing the surface of 21 to have various regular geometric patterns, it is possible to perform the product inspection and the like as described above.

FIG. 14 is a schematic plan view showing the structure of the third embodiment of the piezoelectric device of the present invention. In the figure,
The piezoelectric device 90 shows an example in which a piezoelectric oscillator is formed by using the piezoelectric vibrating piece 32, and the portions denoted by the same reference numerals as those in the first embodiment have the same configuration, and thus the duplicate description will be omitted. The description will be omitted, and the differences will be mainly described.

FIG. 14 is a schematic sectional view of the piezoelectric device 90. The package 86 is manufactured by using more laminated substrates of ceramic sheets than the package 36 of the first embodiment at the time of manufacturing. There is. As a result, in the package 86, as shown in FIG. 14, a recess 87 is formed near the center by utilizing the increased number of laminated substrates.
An electrode (not shown) is provided on the inner bottom portion thereof.
An integrated circuit 88 is mounted on this electrode. The integrated circuit 88 constitutes a predetermined frequency dividing circuit and the like, and is electrically connected to the drive electrode of the piezoelectric vibrating piece 32.
The drive voltage output from the piezoelectric vibrating piece 32 is applied to the piezoelectric vibrating piece 32.

The lead-out electrode 71 of the piezoelectric vibrating reed 32 housed in the piezoelectric device 90 has the structure described in the first embodiment, the structure of each modification of the first embodiment, or the second structure.
It can have the same structure as the extraction electrode of the above embodiment. This makes it possible to exhibit common operational effects based on these configurations. As described above, the present invention is not limited to the piezoelectric vibrator, and the piezoelectric oscillator, the filter, and the like shown in FIG. 14, regardless of their names, house the piezoelectric vibrating piece in the package and seal it with the lid. It can be applied to all piezoelectric devices.

FIG. 15 is a diagram showing a schematic configuration of a digital portable telephone device as an example of an electronic apparatus using the piezoelectric device according to the above-described embodiment of the present invention. In the figure, a microphone 308 for receiving the voice of the sender and a speaker 309 for outputting the received content as a voice are provided, and further, an integrated circuit or the like as a control unit connected to a modulation and demodulation unit of a transmission / reception signal. Controller 3
It is equipped with 01. The controller 301 includes an information input / output unit 302 including an LCD as an image display unit and operation keys for inputting information, in addition to modulation and demodulation of transmission / reception signals.
Alternatively, it controls the information storage means 303 including a RAM and a ROM. Therefore, the controller 30
1, for example, a piezoelectric device 30 is attached,
The output frequency is used as a clock signal suitable for the control content by a predetermined frequency dividing circuit (not shown) incorporated in the controller 301. The piezoelectric device 30 attached to the controller 301 is
Even if the piezoelectric device 30 is not a single unit, the piezoelectric device 30
A piezoelectric device 90 as shown in FIG. 14 which is an oscillator in which a frequency division circuit and a predetermined frequency dividing circuit are combined may be used.

The controller 301 is further connected to a temperature-compensated crystal oscillator (TCXO) 305, and the temperature-compensated crystal oscillator 305 is connected to a transmitter 307 and a receiver 306. As a result, even if the basic clock from the controller 301 changes when the environmental temperature changes,
The transmitter 3 is modified by the temperature-compensated crystal oscillator 305.
07 and the receiving unit 306.

As described above, by using the piezoelectric device according to the above-described embodiment in the electronic device such as the portable telephone device 300 having the control unit, in the bonding structure of the piezoelectric vibrating reed and the electrode in the package, Since the piezoelectric device has excellent impact resistance and can improve the adhesive force, the performance of the piezoelectric device is improved and an accurate clock signal can be generated.

The present invention is not limited to the above embodiments.
As the structure of the piezoelectric vibrating piece, various types such as a tuning fork type or an AT vibrating piece can be used. Further, the respective configurations of the respective embodiments can be appropriately combined with each other, or some of them can be omitted and combined with other configurations not shown.

[0058]

As described above, according to the present invention, in the bonding structure of the piezoelectric vibrating reed and the electrode in the package, a piezoelectric device having excellent impact resistance and improved adhesive strength, and It is possible to provide a manufacturing method and a mobile phone device and an electronic device using the piezoelectric device.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a first embodiment of a piezoelectric device of the present invention.

FIG. 2 is a schematic plan view showing the first embodiment of the piezoelectric device of the present invention.

3 is a schematic cross-sectional view taken along the line CC of FIG.

4 is a partially enlarged view of a piezoelectric vibrating piece of the piezoelectric device of FIG. 1, (a) is a partially enlarged plan view, and (b) is FIG.
(A) BB line cutting | disconnection end view.

FIG. 5 is a diagram showing a first modification of the first embodiment of the piezoelectric device of the present invention, and a partially enlarged plan view of the piezoelectric vibrating piece.

6A to 6C are manufacturing process diagrams for forming extraction electrodes on the piezoelectric vibrating piece of the piezoelectric device of FIG.

FIG. 7 is a manufacturing process diagram for forming extraction electrodes on the piezoelectric vibrating piece of the piezoelectric device shown in FIG.

FIG. 8 is a diagram showing a second modification of the first embodiment of the piezoelectric device of the present invention, and FIG. 8A is a partially enlarged plan view of the piezoelectric vibrating piece in which the extraction electrode is properly formed. ,
FIG. 6B is a partially enlarged plan view of a case where the extraction electrode of the piezoelectric vibrating reed is improperly formed.

FIG. 9 is a diagram showing a third modification example of the first embodiment of the piezoelectric device of the present invention, and a partially enlarged plan view of the piezoelectric vibrating piece.

FIG. 10 is a diagram showing a fourth modification of the first embodiment of the piezoelectric device of the present invention, and a partially enlarged plan view of the piezoelectric vibrating piece.

FIG. 11 is a diagram showing a fifth modification of the first embodiment of the piezoelectric device of the present invention, and FIG. 11A is a partially enlarged plan view of the piezoelectric vibrating piece in which the extraction electrode is properly formed. , (B) is a partially enlarged plan view in the case where the extraction electrode of the piezoelectric vibrating reed is improperly formed.

FIG. 12 is a partially enlarged view of the piezoelectric vibrating piece of the second embodiment of the piezoelectric device of the present invention, (a) is a partially enlarged plan view, and (b) is a sectional view taken along line BB of FIG. 4 (a). End view.

FIG. 13 is a manufacturing process diagram for forming extraction electrodes on the piezoelectric vibrating piece of the piezoelectric device shown in FIG.

FIG. 14 is a schematic plan view of a third embodiment of the piezoelectric device of the present invention.

FIG. 15 is a diagram showing a schematic configuration of a digital mobile phone device as an example of an electronic apparatus using the piezoelectric device according to each embodiment of the present invention.

FIG. 16 is a schematic plan view showing an example of a conventional piezoelectric device.

17 is a schematic cross-sectional view taken along the line AA of FIG.

18 is a partially enlarged view of the piezoelectric vibrating piece of the piezoelectric device of FIG. 16, (a) is a partially enlarged plan view, and (b) is FIG.
8A is a sectional view taken along line EE of FIG.

FIG. 19 is a partially enlarged view of a piezoelectric vibrating reed studied as a structure different from the piezoelectric device of FIG. 18, (a) is a partially enlarged sectional view of the study example, and (b) is a portion of another study example. Enlarged sectional view.

[Explanation of symbols]

20, 30, 90 ... Piezoelectric device, 31 ... Electrode part, 32 ... Piezoelectric vibrating piece, 36, 86 ... Package, 43 ... Conductive adhesive, 71, 81, 82, 8
3, 84, 85 ... Extraction electrode, 39 ... Lid body.

Claims (12)

[Claims] 1. A piezoelectric vibrating reed is housed in an internal space of a package, and an electrode provided inside the package and a lead electrode of the piezoelectric vibrating reed are joined by a silicone-based conductive adhesive, whereby A piezoelectric device configured to fix a part of a piezoelectric vibrating piece, wherein the extraction electrode is provided on an underlayer provided on a surface side of a material forming the piezoelectric vibrating piece and on a surface side of the underlayer. A surface noble metal layer of a noble metal, the surface noble metal layer facing at least the package-side electrode of the extraction electrode, the underlying layer is partially exposed, the piezoelectric device. 2. The piezoelectric device according to claim 1, wherein a material layer of the piezoelectric vibrating piece is partially exposed in the surface noble metal layer, instead of the base layer. 3. The surface layer or the material layer of the piezoelectric vibrating piece which is partially exposed to the surface precious metal layer, and the surface precious metal layer are formed in a regular geometric shape. The piezoelectric device according to claim 1 or 2. 4. The material layer of the piezoelectric vibrating piece is quartz.
The piezoelectric device according to claim 1, wherein the underlayer is made of chromium (Cr) or a chromium alloy. 5. The material layer of the piezoelectric vibrating piece is quartz.
The piezoelectric device according to claim 1, wherein the surface noble metal layer is gold (Au) or a gold alloy. 6. A method of manufacturing a piezoelectric device, comprising the step of accommodating a piezoelectric vibrating reed in an internal space of a package and joining an electrode provided inside the package and the piezoelectric vibrating reed, the piezoelectric vibrating reed. Of the extraction electrode forms an underlayer on the surface side of the material layer of the piezoelectric vibrating piece, then forms a surface noble metal layer on the surface side of this underlayer, and further partially peels off the surface noble metal layer. Thus, at least the surface of the extraction electrode facing the electrode on the package side is formed so that the underlying layer is partially exposed, and in the bonding step of the piezoelectric vibrating piece, the electrode surface on the package side is formed. And a conductive conductive adhesive of silicone type is applied between the surface of the lead-out electrode where the underlying layer is exposed, so that the electrode on the package side and the piezoelectric vibrating piece are pulled out. A method for manufacturing a piezoelectric device, which is characterized in that it is joined to an output electrode. 7. The material layer of the piezoelectric vibrating piece is partially exposed instead of the underlayer on at least a surface of the lead electrode facing the electrode on the package side. The method for manufacturing a piezoelectric device according to claim 6, wherein 8. The underlying layer or the material layer of the piezoelectric vibrating piece partially exposed to the surface noble metal layer and the surface noble metal layer are formed in a regular geometric shape. A method for manufacturing the piezoelectric device according to claim 6. 9. The material layer of the piezoelectric vibrating piece is quartz.
9. The method for manufacturing a piezoelectric device according to claim 6, wherein the underlayer is made of chromium (Cr) or a chromium alloy. 10. The piezoelectric device according to claim 6, wherein the material layer of the piezoelectric vibrating piece is quartz, and the surface noble metal layer is gold (Au) or a gold alloy. Manufacturing method. 11. A piezoelectric vibrating reed is housed in an internal space of a package, and an electrode provided inside the package and a lead-out electrode of the piezoelectric vibrating reed are joined by a silicone-based conductive adhesive, whereby A mobile phone device using a piezoelectric device configured to fix a part of a piezoelectric vibrating piece, wherein the extraction electrode is an underlayer provided on a front surface side of a material forming the piezoelectric vibrating piece, and the underlayer. A surface noble metal layer made of a noble metal provided on the surface side of the piezoelectric element in which the underlying layer is partially exposed in the surface noble metal layer facing at least the package side electrode of the extraction electrode. A mobile phone, characterized in that a clock signal for control is obtained by a device or a piezoelectric device in which a material layer of the piezoelectric vibrating piece is partially exposed. Location. 12. A piezoelectric vibrating reed is housed in an internal space of a package, and an electrode provided inside the package and a lead-out electrode of the piezoelectric vibrating reed are joined by a silicone-based conductive adhesive, whereby An electronic device using a piezoelectric device configured to fix a part of a piezoelectric vibrating piece, wherein the extraction electrode is a base layer provided on a surface side of a material forming the piezoelectric vibrating piece, and A piezoelectric device having a surface noble metal layer formed of a noble metal provided on the front surface side, wherein the underlayer is partially exposed in the surface noble metal layer facing at least the electrode on the package side of the extraction electrode. Alternatively, the electronic device is characterized in that a clock signal for control is obtained by a piezoelectric device in which a material layer of the piezoelectric vibrating piece is partially exposed.