JP2010226396A - Piezoelectric device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric device capable of preventing leakage of underfill materials or mold resins filled between packages and substrates for packaging, and to provide a method of manufacturing a piezoelectric device for manufacturing the piezoelectric device. <P>SOLUTION: A piezoelectric oscillator 1 includes: the substrate 4 for packaging, formed in a nearly rectangular shape in a plan view; a package 3 that is placed on the substrate 4 for packaging and stores a piezoelectric vibration reed 2; and an electronic component 6 provided between the substrate 4 for packaging and the package 3. Also, edges of a pair of sides opposite to the substrate 4 for packaging are bent upward entirely, and a packaging terminal 43 is provided on a lower surface of a bent section 401. Then, a mold resin (not shown) is filled between the substrate 4 for packaging and the package 3. The piezoelectric oscillator 1 is soldered to the circuit board, thus forming a solder reservoir in a gap generated at a lower portion of the bent section 401. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a piezoelectric device and a method for manufacturing a piezoelectric device.

A piezoelectric device such as a crystal oscillator generally includes a piezoelectric element such as a crystal resonator and an electronic component such as an IC element that drives the piezoelectric element. As such a piezoelectric device, for the purpose of downsizing and the like, a device having a configuration in which a piezoelectric element and an electronic component are mounted on a substrate so as to overlap is known.
For example, in the piezoelectric oscillator described in Patent Document 1, a package containing a piezoelectric vibrator is placed on a mounting substrate, and an electronic component is provided between the package and the mounting substrate. .

FIG. 10 is a cross-sectional view (a) showing a conventional piezoelectric oscillator and a top view (b) of a mounting substrate provided in the piezoelectric oscillator.
A piezoelectric oscillator 900 shown in FIG. 10 includes a mounting substrate 901 and a package 903 having an electronic component 902 and a piezoelectric vibrator arranged thereon.
Two notches 910 are formed at both ends in the longitudinal direction of the mounting substrate 901 as shown in FIG. And the center part of the width direction pinched | interposed by these notches 910 is bend | folded upward as shown to Fig.10 (a), and forms the bending part 911. FIG. The package 903 is fixed on the mounting substrate 901 by joining the tip of the bent portion 911 and the bottom surface of the package 903. In addition, mounting terminals 912 are provided on the lower surface of portions other than the bent portion 911 among the both ends of the mounting substrate 901, that is, on the lower surfaces of the four corners of the mounting substrate 901.

On the other hand, the circuit board 920 shown in FIG. 10 includes an insulating substrate 921 and circuit wiring 922 provided on the upper surface thereof.
When the piezoelectric oscillator 900 described above is mounted on the circuit board 920, the piezoelectric oscillator 900 is placed on the circuit board 920 so that the mounting terminal 912 of the piezoelectric oscillator 900 and the circuit wiring 922 of the circuit board 920 face each other. For example, the mounting terminal 912 and the circuit wiring 922 are soldered. As a result, the piezoelectric oscillator 900 is fixed on the circuit board 920 via the solder layer 923.
By using the mounting substrate 901 provided with the bent portion 911 in this manner, the package 3 can be fixed on the mounting substrate 901 without using a spacer or the like, so that the structure of the piezoelectric oscillator 900 can be simplified. It is done.

Incidentally, an underfill material 913 is filled between the package 903 of the piezoelectric oscillator 900 and the mounting substrate 901 as shown in FIG.
However, the underfill material 913 may leak from the notch 910 and adhere to the mounting terminals as shown in FIG. Therefore, conventionally, it has been necessary to take measures such as wiping out the leaked underfill material 913 and closing the notch 910. For this reason, the structure of the piezoelectric oscillator 900 is complicated, and the manufacturing process is complicated.

JP 2007-281597 A

  An object of the present invention is to provide a piezoelectric device capable of preventing leakage when an underfill material or a mold resin is filled between a package and a mounting substrate, and a method for manufacturing the piezoelectric device for manufacturing such a piezoelectric device. There is.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.
[Application Example 1]
The method for manufacturing a piezoelectric device of the present invention is provided between a mounting substrate, a package provided on one surface side of the mounting substrate, containing a piezoelectric vibrating piece, and the mounting substrate and the package. A method of manufacturing a piezoelectric device having an electronic component for driving the piezoelectric vibrating piece,
Preparing a mounting substrate film in which a plurality of regions to be the mounting substrate are connected, and placing each electronic component on one surface side of each region;
A package mounting step of stacking and mounting the packages so as to sandwich the electronic components with respect to the mounting substrate film;
A folding step of bending a whole pair of opposing edges of the region to the package side to form a bent portion, and fixing a part of the bent portion to the package;
A resin filling step of filling a resin between the mounting substrate film and the package and covering the electronic component with the resin;
And a cutting step of cutting the boundaries between the regions of the mounting substrate film into pieces into a plurality of the piezoelectric devices.
As a result, when mounted on a substrate or the like, it is possible to make the connection portion easy to see while reducing the height, and to enable highly reliable connection, and when the resin is filled, A plurality of piezoelectric devices capable of preventing leakage can be manufactured simultaneously and efficiently.

[Application Example 2]
In the method for manufacturing a piezoelectric device according to the aspect of the invention, it is preferable that the package placing step includes a step of bonding the package to each electronic component with an adhesive.
Thereby, it can prevent that a void generate | occur | produces between an electronic component and a package when it fills with resin.

[Application Example 3]
In the piezoelectric device manufacturing method of the present invention, the mounting substrate film is connected to the region to be the mounting substrate and the region, and is electrically connected to the electronic component in the electronic component mounting step. And an extended portion having an adjustment terminal,
It is preferable that after the package mounting step, there is an adjustment step of rewriting information on the electronic component via the adjustment terminal and then separating the region and the extended portion.
As a result, even if the usage environment of the piezoelectric device changes significantly after the manufacture of the piezoelectric device, a piezoelectric device capable of stable oscillation can be manufactured by rewriting various information in the electronic component according to the usage environment. Can do.

[Application Example 4]
The piezoelectric device of the present invention includes a mounting substrate,
A package provided on one side of the mounting substrate and containing a piezoelectric vibrating piece;
An electronic component provided between the mounting substrate and the package for driving the piezoelectric vibrating piece;
The mounting substrate has a bent portion formed by bending the entire pair of opposing edges to the package side,
A part of the bent portion is fixed to the package;
A resin is filled between the mounting substrate and the package, and the electronic component is covered with the resin.
Thereby, a piezoelectric device capable of preventing leakage when resin is filled between the package and the mounting substrate is obtained.

[Application Example 5]
In the piezoelectric device of the present invention, it is preferable to have a mounting terminal provided on the surface of the bent portion opposite to the package.
As a result, when the piezoelectric device is mounted on a substrate or the like, it is possible to make the connection portion easy to see while reducing the height, and to obtain a piezoelectric device capable of highly reliable connection.

[Application Example 6]
In the piezoelectric device according to the aspect of the invention, the bent portion includes an inclined portion that is inclined with respect to the electronic component mounting portion on which the electronic component of the mounting substrate is mounted, and a portion that extends to the outer edge side from the inclined portion. Having a tip and
The tip portion is preferably fixed to the package.

  Thereby, the stress of a surface direction is easy to be relieved because the inclination-angle of an inclination part changes freely. For this reason, when the piezoelectric device is mounted on the base material, it is possible to more reliably suppress the occurrence of problems associated with stress concentration. Further, since the tip end portion is substantially parallel to the other portion, the tip end portion is also substantially parallel to the package, and is reliably bonded to the package with a sufficient area.

[Application Example 7]
In the piezoelectric device according to the aspect of the invention, it is preferable that the mounting terminal is provided on the inclined portion.
Thereby, when a piezoelectric device is mounted on a base material, an area required for the mounting can be further reduced. For this reason, the area | region on a base material can be used effectively, for example, when a base material is a circuit board, the wiring density of circuit wiring can be raised more. As a result, the circuit board can be reduced in size.

[Application Example 8]
In the piezoelectric device according to the aspect of the invention, it is preferable that the mounting substrate is made of a flexible material.
Thereby, since flexibility is given to the mounting substrate, the mounting substrate itself can alleviate stress concentration.

It is a disassembled perspective view which shows the piezoelectric oscillator to which embodiment of the piezoelectric device of this invention is applied. It is the (a) top view and (b) bottom view which show typically the piezoelectric oscillator shown in FIG. It is the sectional view on the AA line of FIG. It is a top view which shows typically the mounting board | substrate with which a piezoelectric oscillator is provided. It is sectional drawing for demonstrating the method to mount the piezoelectric oscillator shown in FIG. 1 on a circuit board. It is the elements on larger scale which show the other structural example of the connection part formed in the clearance gap between a mounting terminal and circuit wiring. It is a conceptual diagram which shows the board | substrate film for mounting for manufacturing the board | substrate for mounting with which the piezoelectric oscillator shown in FIG. 1 is provided. It is a figure for demonstrating the manufacturing method of the piezoelectric oscillator shown in FIG. It is a figure for demonstrating the manufacturing method of the piezoelectric oscillator shown in FIG. It is sectional drawing (a) which shows the conventional piezoelectric oscillator, and the top view (b) of the mounting board | substrate with which a piezoelectric oscillator is provided.

Hereinafter, a piezoelectric device and a method for manufacturing the piezoelectric device of the present invention will be described in detail based on embodiments shown in the accompanying drawings.
FIG. 1 is an exploded perspective view showing a piezoelectric oscillator to which an embodiment of a piezoelectric device of the present invention is applied, and FIG. 2 is a schematic top view of the piezoelectric oscillator shown in FIG. 3 is a cross-sectional view taken along line AA of FIG. 2, and FIG. 4 is a plan view schematically showing a mounting substrate provided in the piezoelectric oscillator. In the following description, the front side of the paper surface in FIG. 2A is referred to as “upper”, and the back side of the paper surface is referred to as “lower”. In FIG. 1, the mold resin that covers the piezoelectric oscillator is omitted.

(Piezoelectric oscillator)
First, a piezoelectric oscillator will be described as an example of an embodiment of a piezoelectric device of the present invention.
A piezoelectric oscillator 1 shown in FIG. 1 is mounted so as to be housed between a package 3 for housing a piezoelectric vibrating piece 2, a mounting substrate 4 for mounting (fixing) the package 3, and the package 3 and the mounting substrate 4. And an electronic component 6 provided on the circuit board 4.

Hereinafter, each part which comprises the piezoelectric oscillator 1 is demonstrated in detail sequentially.
First, the piezoelectric vibrating piece 2 will be described.
In the present embodiment, the piezoelectric vibrating piece 2 is a tuning-fork type quartz vibrating piece as shown in FIG. As shown in FIG. 2, the piezoelectric vibrating piece 2 includes a piezoelectric substrate 21 having a longitudinal shape and a tuning fork shape, and two excitation electrodes (not shown) formed on the surface of the piezoelectric substrate 21. ing.

The piezoelectric substrate 21 is made of a piezoelectric material. Examples of the piezoelectric material include crystal, lithium tantalate, lithium niobate, lithium borate, and barium titanate.
The excitation electrode applies an electric field to the piezoelectric substrate 21. When an electric field is applied to the excitation electrode, the piezoelectric substrate 21 can be vibrated at a certain frequency (resonance frequency) due to the inverse piezoelectric effect of the piezoelectric material. When the piezoelectric substrate 21 vibrates, a voltage having a certain frequency is generated between the two excitation electrodes due to the piezoelectric effect of the piezoelectric material. Utilizing these properties, the piezoelectric vibrating reed 2 can generate an electrical signal that vibrates at a resonance frequency.

Next, the package 3 for housing and fixing the piezoelectric vibrating piece 2 will be described.
The package 3 has a substantially square shape or a substantially rectangular shape in plan view. As shown in FIG. 3, such a package 3 includes a plate-like base substrate 31 having a concave portion corresponding to the internal space S <b> 1 in the central portion, and a lid member that is stacked on the base substrate 31 so as to cover the concave portion. 32. The base substrate 31 and the lid member 32 are joined by an adhesive or a brazing material. The package 3 accommodates the piezoelectric vibrating reed 2 in an internal space S1 defined by the base substrate 31 and the lid member 32. In FIG. 2A, the lid member 32 is shown in a transparent manner.

As the constituent material of the base substrate 31, those having insulating properties (non-conductive) are preferable. For example, various glass materials, various ceramic materials such as oxide ceramics, nitride ceramics, carbide ceramics, polyimide, etc. Various resin materials can be used.
Further, as the constituent material of the lid member 32, for example, the same constituent material as that of the base substrate 31, various metal materials such as Al and Cu, various glass materials, and the like can be used. In particular, when a light-transmitting material such as a glass material is used as the constituent material of the lid member 32, the piezoelectric vibrating piece 2 can be obtained by previously forming a metal cover (not shown) on the piezoelectric substrate 21. Even after the substrate 3 is accommodated in the package 3, the metal cover is irradiated with a laser through the lid member 32, and the metal cover is removed to reduce the mass of the piezoelectric substrate 21 (mass). The frequency of the piezoelectric vibrating piece 2 can be adjusted by the reduction method.

  As shown in FIG. 3, a pair of mount electrodes 34 is formed on the bottom surface of the recess (internal space S <b> 1) of the base substrate 31. On the mount electrode 34, an epoxy-based or polyimide-based conductive adhesive 39 containing conductive particles is applied (stacked), and further on the conductive adhesive 39. The piezoelectric vibrating reed 2 described above is placed. Then, by curing the conductive adhesive 39, the piezoelectric vibrating reed 2 is cantilevered by the mount electrode 34 (base substrate 31).

By this fixing, one of the pair of mount electrodes 34 is electrically connected to one of the two excitation electrodes provided on the piezoelectric vibrating piece 2 via the conductive adhesive 39. The other mount electrode 34 is also electrically connected to the other excitation electrode through the conductive adhesive 39.
Further, since the piezoelectric vibrating piece 2 is fixed by adhering the left end of the piezoelectric vibrating piece 2 to the base substrate 31, when the piezoelectric vibrating piece 2 vibrates, the left side of the piezoelectric vibrating piece 2 is fixed. The end is the “fixed end”, while the right end is the “free end”.

As shown in FIG. 2A, external terminals 35 are provided on the lower surface of the base substrate 31 in the vicinity of the four corners.
Two of these four external terminals 35 are electrically connected to the two mount electrodes 34 described above.
Each of the mount electrodes 34 and the external terminals 35 can be formed by applying gold plating to an underlying layer of tungsten and nickel plating, for example.

Next, the mounting substrate 4 on which such a package 3 is placed will be described.
As shown in FIG. 1, the mounting substrate 4 is a substrate on which the package 3 and an electronic component 6 to be described later are placed, and has a substantially square shape or a substantially rectangular shape in plan view. The substrate is approximately the same size as the substrate 31.
Such a mounting substrate 4 has an insulating substrate 40, a plurality of electrode terminal portions 41 provided on the upper surface (surface on the package 3 side), and two wiring patterns 42.

  Among these, the insulating substrate 40 may be a rigid substrate, a flexible substrate, or a rigid flexible substrate, but is preferably a flexible substrate from the viewpoint of ease of processing. In addition, the constituent material of the insulating substrate 40 is preferably an insulating (non-conductive) material. Examples of the constituent material of the rigid substrate include various glasses, oxide ceramics, and nitride ceramics. And ceramics such as carbide-based ceramics. As the constituent material of the flexible substrate, various resin materials such as polyimide, polyethylene, polypropylene, and polyethylene terephthalate can be used.

Further, as shown in FIG. 3, the plurality of electrode terminal portions 41 are spaced apart from each other in correspondence with the pad portions 61 of the electronic component 6.
These electrode terminal portions 41 are terminals for driving the piezoelectric vibrating reed 2, as well as characteristic inspection of the electronic component 6 and rewriting of various information in the electronic component 6 (for example, temperature compensation information of the piezoelectric oscillator 1). A write terminal, an input / output terminal, a ground terminal, and the like.

  Further, as shown in FIG. 1, the entire short side direction of the insulating substrate 40 is upward at both ends in the longitudinal direction of the mounting substrate 4 (a pair of opposed edges or a pair of opposed sides). Two bent portions 401 and 401 are formed to be bent so as to protrude. In each bent portion 401, bent lines 402a and 402b are formed at the root portion and the tip portion, respectively. As a result, each of the bent portions 401 is bent upward along the fold line 402a, and the region on the distal end side of the fold line 402a and the proximal end side of the fold line 402b is located on a portion other than the bent portion 401 of the insulating substrate 40. It becomes the inclined part 401a inclined with respect to it. On the other hand, the bending line 402b is bent downward, so that the region on the tip side of the bending line 402b becomes a tip portion 401b substantially parallel to the portion other than the folding portion 401 of the insulating substrate 40.

  Although the inclination angle of the inclined portion 401a, that is, the angle formed between the portion other than the bent portion 401 of the insulating substrate 40 and the inclined portion 401a is not particularly limited, it is preferably about 5 to 80 °, preferably about 10 to 70 °. It is more preferable that it is about 20 to 60 °. When two inclination angles are considered, the smaller angle is referred to as the “inclination angle”.

Moreover, although the height of the front-end | tip part 401b changes according to the size of the piezoelectric oscillator 1, the thickness of the electronic component 6, etc., as an example, Preferably it is about 0.2-3 mm, More preferably, it is about 0.3-2 mm. It is said.
Further, as shown in FIG. 2B, the mounting substrate 4 is formed with a notch 404 for separating each bent portion 401 from other regions (electronic component mounting portion on which the electronic component 6 is mounted). Has been. That is, a plurality of the notches 404 are formed at the base portion of each bent portion 401 along the bend line 402a. By providing the cuts 404 in this way, the mounting substrate 4 can be easily folded along the folding line 402a, and the influence of the bending is applied to other regions in the longitudinal direction of the mounting substrate 4. It has become impossible to reach.

Each notch 404 includes a groove, a recess, or the like formed in the mounting substrate 4.
In addition, as shown in FIGS. 3 and 4, the two wiring patterns 42 have one end connected to one of the plurality of electrode terminal portions 41, and the other end is mounted. It is formed so as to extend toward the left end of the substrate 4 for use.
The other end of each wiring pattern 42 extends away from each other until it reaches the tip 401b through the inclined portion 401a of the bent portion 401 formed at the left end of the mounting substrate 4. Further, the other end of each wiring pattern 42 has a wide line width. Thereby, each wiring pattern 42 has improved connectivity with the external terminal 35 of the package 3 described above.

  On the other hand, in the bent portion 401 formed at the right end portion of the mounting substrate 4, two connection patterns 48, 48 used for joining with the external terminals 35 of the package 3 are provided apart from each other. That is, in the mounting substrate 4, the package 3 is fixed by bonding or bonding between the two wiring patterns 42, 42 and the two connection patterns 48, 48 and the external terminals 35 of the package 3.

  In addition, mounting terminals 43 are formed on the lower surface of each bent portion 401 of the mounting substrate 4. Each mounting terminal 43 is a terminal for electrical and mechanical connection with a circuit board on which the piezoelectric oscillator 1 is mounted. Each mounting terminal 43 is electrically connected to each electrode terminal portion 41 through a conductor post 45 and a wiring pattern 46 provided in a via hole formed in the mounting substrate 4.

An electronic component 6 is placed on the center of the upper surface of the mounting substrate 4. The electronic component 6 is, for example, an integrated circuit element (IC) and has a function of driving the piezoelectric vibrating piece 2.
As shown in FIG. 3, the electronic component 6 is mounted by so-called face-down bonding via bumps (projection electrodes) 44 formed on the electrode terminal portions 41. Thereby, each pad part 61 and each electrode terminal part 41 of the electronic component 6 are electrically connected, and the electronic component 6 is fixed to the mounting substrate 4.

The electronic component 6 may be electrically connected by so-called wire bonding using a metal wire instead of fail-down bonding.
In addition, the package 3 is placed on the front end portion 401 b of each bent portion 401 of the mounting substrate 4. As a result of the package 3 being placed on the tip 401b, the package 3 was lifted from the center of the mounting substrate 4 by the protruding height of each bent portion 401, as shown in FIGS. It is in a state. This eliminates the need for a spacer, a pillar member, and the like for lifting the package 3 as in the prior art, and a reduction in height due to simplification of the structure of the piezoelectric oscillator 1 can be achieved.

Further, as described above, the tip 401b of each bent portion 401 of the mounting substrate 4 and the external terminal 35 of the package 3 are joined or connected by a conductive member such as solder (brazing material) or a conductive adhesive. It is glued. Since the front end portion 401b is a region substantially parallel to the lower surface of the package 3, it can be reliably bonded to the package 3 with a sufficient area.
In addition, as a result of joining each bending part 401 and the package 3, the electronic component 6 will be in the state by which the lower surface and side surface were covered with the board | substrate 4 for mounting. As a result, the mounting substrate 4 can protect the electronic component 6 from impacts, intrusion of foreign matter, and the like, and can improve the durability and reliability of the piezoelectric oscillator 1.

The piezoelectric oscillator 1 is partially molded with a mold resin 7. This reinforces the bonding between the package 3 and the mounting substrate 4 and protects each. For the mold resin 7, for example, various thermosetting resin materials are suitable.
In FIG. 3, the mold resin 7 is provided so as to cover the outer peripheral portion of the lid member 32, the gap between the package 3 and the mounting substrate 4, and the side surfaces of the package 3 and the mounting substrate 4.

(Piezoelectric oscillator mounting method)
Next, a method for mounting the piezoelectric oscillator 1 on a circuit board will be described.
FIG. 5 is a cross-sectional view for explaining a method of mounting the piezoelectric oscillator shown in FIG. 1 on a circuit board. In the following description, the upper side in FIG. 5 is referred to as “upper” and the lower side is referred to as “lower”. In FIG. 5, the mold resin that covers the piezoelectric oscillator is omitted.

The piezoelectric oscillator 1 is mounted on a circuit board via, for example, solder, anisotropic conductive paste or the like.
The mounting method is not particularly limited, such as a reflow method or a flow method, but the reflow method will be described here.
Specifically, the reflow mounting method includes a step of supplying a solder paste to a location where the piezoelectric oscillator 1 is mounted on the circuit board, a step of mounting the piezoelectric oscillator 1 on the circuit board, and the piezoelectric oscillator 1 A step of heating (reflowing) the mounted circuit board by heating, melting and solidifying the solder.

Hereinafter, each step will be described.
First, a solder paste is supplied onto the circuit wiring 81 of the circuit board 8.
The solder paste is a paste obtained by mixing solder powder or flux with a binder.
The supply of the solder paste can be performed using, for example, a dispenser in addition to various printing methods such as screen printing.

Next, the piezoelectric oscillator 1 is placed on the supplied solder paste. The position of the mounted piezoelectric oscillator 1 is held by the viscosity of the solder paste.
Next, the circuit board 8 on which the piezoelectric oscillator 1 is mounted is heated by a reflow furnace. Although heating temperature is suitably set according to the kind of solder, it is set as about 220-260 degreeC as an example.
By such heating, the binder component in the solder paste is first decomposed and removed. Thereafter, when the heating temperature exceeds the melting point of the solder, the solder is melted and spreads between the circuit wiring 81 of the circuit board 8 and each mounting terminal 43 of the piezoelectric oscillator 1.

Thereafter, the circuit board 8 is radiated to solidify the solder, and the piezoelectric oscillator 1 is mounted on the circuit board 8.
Here, the molten solder between the mounting terminal 43 and the circuit wiring 81 wets and spreads so as to fill a gap between the mounting terminal 43 and the circuit wiring 81 as shown in FIG. Further, since the mounting terminal 43 is formed on the lower surface of the bent portion 401 of the mounting substrate 4 of the piezoelectric oscillator 1, a gap 9 is generated between the mounting terminal 43 and the circuit wiring 81. . As shown in FIG. 5, the melted solder is formed so as to fill the gap 9 with a gently curved shape called a “fillet” (fillet 92 shown in FIG. 5) on the opening side of the gap 9. It becomes a solder pool. Such a solder pool is solidified, and the connection part 91 shown in FIG. 5 is formed.

In the conventional piezoelectric oscillator, since there was almost no gap with the circuit board, even if it tried to visually recognize a connection part, the visible area was very small. For this reason, in the inspection process, it was extremely difficult to directly look at the fillet and find defects such as cracks occurring in the connection portion.
Further, a difference in thermal expansion coefficient generally exists between the piezoelectric oscillator and the circuit board, but this thermal expansion coefficient difference may cause stress concentration on the connection portion after mounting. In the conventional solder accumulated in a layer shape, such stress concentration cannot be alleviated, and a crack or the like may occur in the connection portion.

On the other hand, in the mounting of the piezoelectric oscillator 1, as shown in FIG. 5, a relatively wide gap 9 is generated between the mounting terminal 43 and the circuit wiring 81 due to the bending of the bent portion 401. Therefore, in the inspection process, the thicker connecting portion 91 formed in the wide gap 9 can be easily visually recognized, and the defect can be easily found.
Further, since the connection portion 91 is a material in which solder is accumulated to a certain thickness, and the solder is a material having a relatively high flexibility, it contributes to relaxation of stress concentration in the connection portion 91. For this reason, even if the stress due to the difference in the thermal expansion coefficient between the piezoelectric oscillator 1 and the circuit board 8 occurs, the connecting portion 91 surely suppresses the occurrence of defects, thereby improving product reliability and manufacturing yield. Can be achieved.

  Furthermore, since the connecting portion 91 fixes the bent portion 401 to the circuit board 8, it contributes to stress relaxation particularly in the lateral direction (direction parallel to the circuit board 8). This is because the bent portion 401 is formed by bending an insulating substrate, and therefore the bending angle (inclination angle of the inclined portion 401a) can be freely changed, so that stress in the lateral direction (surface direction) is particularly changed. It is because it is easy to relax. This tendency is particularly remarkable when the insulating substrate 40 is a flexible substrate (flexible substrate). For this reason, the connecting portion 91 can more reliably suppress the occurrence of problems associated with stress concentration.

  In addition, since the electronic component 6 is mounted between the bent portions 401 formed at both ends of the mounting substrate 4, the mounting position (mounting) of the electronic component 6 is mounted even when the thickness of the connection portion 91 is increased. Almost no effect on (height). For this reason, even if the thickness of the connecting portion 91 is increased, it is difficult to affect the height of the piezoelectric oscillator 1 mounted on the circuit board 8. The entire circuit board 8 on which the oscillator 1 is mounted can be reliably reduced in thickness.

Note that the shape of the connecting portion 91 can take various shapes depending on the formation region of the mounting terminal 43.
FIG. 6 is a partially enlarged view showing another configuration example of the connection portion formed in the gap between the mounting terminal and the circuit wiring.
In the piezoelectric oscillator 1 shown in FIG. 5 described above, the mounting terminal 43 is provided on both the lower surface of the inclined portion 401a and the lower surface of the tip portion 401b in the bent portion 401. On the other hand, the piezoelectric oscillator shown in FIG. 6 is the same as the piezoelectric oscillator 1 shown in FIG. 5 except that the shape of the mounting terminal 43 is different.

That is, the mounting terminal 43 a shown in FIG. 6A is provided only on the lower surface of the tip end portion 401 b in the bent portion 401. When the piezoelectric oscillator 1 having such a mounting terminal 43a is placed on the circuit board 8, a solder pool as shown in FIG. 6A is formed between the mounting terminal 43a and the circuit wiring 81. The connection part 91a is formed when this solidifies.
On the other hand, the mounting terminal 43b shown in FIG. 6B is provided only on the lower surface of the distal end portion 401b in the bent portion 401, like the mounting terminal 43a described above. The piezoelectric oscillator 1 having such mounting terminals 43b is placed on the circuit board 8, and a conductive spherical shape as shown in FIG. 6B is provided between the mounting terminals 43b and the circuit wiring 81. The spacers 93 are connected. Then, a solder pool as shown in FIG. 6B is formed between the mounting terminal 43b and the spacer 93 and between the circuit wiring 81 and the spacer 93, and this solidifies to form the connection portion 91b. Has been.

According to such a connecting portion 91b, the piezoelectric oscillator 1 can be mounted in a state where it is lifted from the circuit board 8 by the diameter of the spacer 93. As a result, a wider gap 9 is formed between the mounting terminal 43 and the circuit wiring 81. As a result, the connecting portion 91b and the fillet 92 can be visually confirmed more reliably.
The spacer 93 includes, for example, a solder layer formed on the surface of particles made of copper.

Also, the mounting terminal 43c shown in FIG. 6C is provided only on the lower surface of the inclined portion 401a in the bent portion 401. When the piezoelectric oscillator 1 having such mounting terminals 43c is placed on the circuit board 8, a solder pool as shown in FIG. 6C is formed between the mounting terminals 43c and the circuit wiring 81. The connection part 91c is formed when this solidifies.
According to such a connection part 91c, the area required for mounting the piezoelectric oscillator 1 can be further reduced. That is, in the case of FIG. 6C, the length L2 necessary for mounting the piezoelectric oscillator 1 on the circuit board 8 is shorter than the length L1 of the piezoelectric oscillator 1. For this reason, the area on the circuit board 8 can be used effectively. For example, the circuit board 8 may have circuit wiring 82 provided so as to enter the gap 9 as shown in FIG. it can. Since this circuit wiring 82 is another wiring different from the circuit wiring 81, according to the mounting form shown in FIG. 6C, the wiring density in the circuit board 8 is reduced without reducing the size of the piezoelectric oscillator 1. Can be increased. As a result, the circuit board 8 can be reduced in size.
Also by the connection portions 91a, 91b, 91c shown in FIG. 6 as described above, the same operations and effects as those of the connection portion 91 shown in FIG. 5 described above can be obtained.

(Piezoelectric oscillator manufacturing method)
Next, a method for manufacturing the piezoelectric oscillator 1 (a method for manufacturing a piezoelectric device of the present invention) will be described.
FIG. 7 is a conceptual diagram showing a mounting substrate film for manufacturing a mounting substrate provided in the piezoelectric oscillator shown in FIG. 1, and FIGS. 8 and 9 are diagrams for explaining a method of manufacturing the piezoelectric oscillator shown in FIG. FIG. 8 and 9 are cross-sectional views taken along line BB in FIG.

A mounting substrate film 100 shown in FIG. 7 is a belt-like film in which regions corresponding to the mounting substrate 4 are connected in a row so that a plurality of piezoelectric oscillators 1 can be formed simultaneously.
The mounting substrate film 100 includes an insulating substrate 40 made of the above-described resin material such as polyimide, an extended portion 4a that extends the insulating substrate 40 to the right side, and a blank portion that extends to the left side. A region having 4b is taken as one unit, and a plurality of these regions are connected. Then, by cutting the mounting substrate film 100 along the cutting line CL shown in FIG. 7, a plurality of temporary substrates 400 including the mounting substrate 4 and the extended portions 4a and blank portions 4b attached thereto are simultaneously formed. Can do. Further, by cutting the temporary substrate 400 obtained in this way along a cutting line CL2 shown in FIG. 7, a plurality of mounting substrates 4 can be formed simultaneously.

In addition, two adjustment terminals 47, 47 are provided on the upper surface of the extended portion 4a, and these are independently connected to the electrode terminal portion 41 via wiring. Thereby, various information in the electronic component 6 can be rewritten via each adjustment terminal 47.
The extended portion 4a and the margin portion 4b may be provided as necessary, and may be omitted.

In the mounting substrate film 100, the electrode terminal portions 41, the wiring patterns 42, the mounting terminals 43, the conductor posts 45, the wiring patterns 46, and the adjustments described above are provided at portions corresponding to the individual mounting substrates 4. Terminals 47, connection patterns 48, notches 404, and the like are formed.
Each electrode terminal portion 41, each wiring pattern 42, each mounting terminal 43, each conductor post 45, each wiring pattern 46, each adjustment terminal 47, and each connection pattern 48 are each made of a conductive material such as copper. It can be formed by combining techniques such as etching, printing, vapor deposition and plating.
In addition, an insulating film may be formed on the entire upper surface of the mounting substrate film 100 in a region that does not require electrical contact, if necessary.

Hereinafter, a method for manufacturing the piezoelectric oscillator 1 will be sequentially described.
First, the electronic component 6 is mounted face-down on the upper surface of the mounting substrate film 100 (electronic component placing step).
Specifically, first, the bump 44 is formed on each pad portion 61 with the surface of the electronic component 6 having the pad portion 61 facing upward. Various bumps, such as plating bumps and metal bumps, can be used as the bumps 44. As an example, the tip of a metal wire used for wire bonding is made into a ball shape by discharge, and then the tip is attached to a pad portion. A so-called stud bump formed by pressing and joining to 61 and then cutting the wire and leaving the tip portion on the pad portion 61 is exemplified. After the formation of the bumps 44, as shown in FIG. 8A, the electronic component 6 is supported from above by the bonding head BH, and the electronic components 6 are mounted so that the bumps 44 and the electrode terminal portions 41 are in contact with each other. It is placed on the substrate film 100 for use. And the electronic component 6 is crimped | bonded to the board | substrate film 100 for mounting, applying an ultrasonic wave with the bonding head BH.

Next, as shown in FIG. 8B, the lower surface of the package 3 and the upper surface of the electronic component 6 are bonded with an adhesive (not shown). Thereby, the package 3 is fixed to the upper surface of the electronic component 6.
Next, the mounting substrate film 100 to which the electronic component 6 and the package 3 are fixed is turned upside down. And each bending part 401 of the board | substrate film 100 for mounting is pushed down as shown in FIG.8 (c) (bending process). And the wiring pattern 42 provided in each bending part 401 and the external terminal 35 provided in the package 3 are connected. Similarly, the connection pattern 48 provided in each bent portion 401 and the external terminal 35 provided in the package 3 are connected. As a result, the wiring pattern 42, the external terminal 35, and the piezoelectric vibrating reed 2 housed in the package 3 are electrically connected. For the connection between the wiring pattern 42 or the connection pattern 48 and the external terminal 35, thermocompression bonding, bonding by bumps, or the like is used.

The mounting substrate film 100 can be bent by, for example, using a jig 51 as shown in FIG. 8C and pressing the jig 51 against the mounting substrate film 100.
Here, in the conventional mounting substrate film, since a plurality of mounting substrates are generally connected in the longitudinal direction, when the bent portion is bent in one region corresponding to the mounting substrate. The film is pulled in the longitudinal direction, and a tensile force is transmitted to an adjacent area, and the position of this area may be shifted.

  On the other hand, in the mounting substrate film 100, as described above, a plurality of temporary substrates 400 are connected in the width direction. For this reason, even if the bent portion 401 is bent in one region corresponding to the mounting substrate 4, the tensile force generated at that time is transmitted in the width direction of the mounting substrate film 100, and It is not transmitted to other areas adjacent in the longitudinal direction. For this reason, according to the mounting substrate film 100, it is possible to reliably prevent the positional deviation as described above.

  Next, the mounting substrate film 100 is turned upside down again, and the space between the package 3 and the mounting substrate film 100 and the outside of the lid member 32 of the package 3 are molded with the mold resin 7. The mold resin 7 is, for example, a method in which a member to be molded is placed in a mold and the mold resin is supplied into the mold (injection mold), a method of supplying by a screen printing method, or a method of filling the gap with the mold resin ( Potting mold) or the like. Here, the potting mold will be described as a representative.

  The mounting substrate film 100 is placed on a pedestal 53 provided at a position corresponding to the extended portion 4a and the blank portion 4b, and the mold 52 is placed on the extended portion 4a and the blank portion 4b. The mold 52 has a cavity that surrounds the package 3 and the mounting substrate 4. Even if the mold 52 surrounds one package 3 and the mounting substrate 4, a plurality of packages 3 and mounting substrates 4 can be formed. It may be something that surrounds it. Then, the mold resin 7 is filled into the cavity of the mold 52 as shown in FIG.

By the way, in the case of the conventional mounting substrate as shown in FIG. 10, since the notch 910 exists, the supplied mold resin leaks out from the notch 910. For this reason, conventionally, a new process such as wiping away the leaked mold resin or covering the leaked mold resin has been required.
On the other hand, in the mounting substrate film 100, since both end portions in the width direction are bent upward, there is no notch, and the mold resin 7 supplied onto the mounting substrate film 100 is below There is no risk of flowing into For this reason, in the mounting substrate film 100, as shown in FIG. 9 (d), it is possible to simply perform resin molding simply by placing the mold 52 on the upper surface.

The mold resin 7 does not need to cover the entire piezoelectric oscillator 1 and can be replaced with a so-called underfill material filled only in the gap between the package 3 and the mounting substrate 4.
Next, the mounting substrate film 100 is cut along a cutting line CL shown in FIG. 7 (cutting step). Thereby, the mounting substrate film 100 is separated into a plurality of temporary substrates 400, and as a result, a plurality of piezoelectric oscillators 1 are manufactured simultaneously.

  Next, various characteristics of each piezoelectric oscillator 1 are inspected, and various information in the electronic component 6 is rewritten as necessary (adjustment process). In addition, as shown in FIG. 9 (e), this information is rewritten by bringing the voltage application probe 54 into contact with the two adjustment terminals 47, 47 provided on the extended portion 4 a and passing through the adjustment terminal 47. Various information in the electronic component 6 can be rewritten. Moreover, you may make it perform this adjustment process after the said package mounting process and before the said bending process.

In addition, each adjustment terminal 47 is provided in the extended portion 4 a, so that it is not hidden behind the package 3 or the mold resin 7. For this reason, even after supplying the mold resin 7, it is possible to rewrite various information in the electronic component 6 by applying a voltage to each adjustment terminal 47.
Furthermore, since each adjustment terminal 47 has been conventionally formed on the lower surface of the mounting substrate 4, the size of the adjustment terminal 47 cannot be increased in view of ensuring insulation with the adjacent mounting terminals 43. For this reason, when various information of the electronic component 6 is rewritten, it is difficult to control the position of the probe 54 to be brought into contact with each adjustment terminal 47, and it is easy to cause poor connection. On the other hand, in the temporary substrate 400 shown in FIG. 9E, the adjustment terminals 47 are provided in the extended portion 4a. Therefore, the sizes of the adjustment terminals 47 can be sufficiently increased, and the mounting terminals 43 are provided. And the adjustment terminal 47 can be sufficiently increased in distance. As a result, the position control of the probe 54 as described above becomes easy, and the occurrence of connection failure can be reliably prevented.

Further, if necessary, the frequency of the piezoelectric vibrating piece 2 can be adjusted by irradiating the piezoelectric vibrating piece 2 in the package 3 with laser light so as to pass through the lid member 32 and using the mass reduction method described above.
Note that after the information is rewritten, the temporary substrate 400 is cut along the cutting line CL2 shown in FIG. Thereby, the temporary board | substrate 400 is isolate | separated into the insulating board | substrate 40, the expansion part 4a, and the margin part 4b, respectively. As a result, the mounting substrate 4 (piezoelectric oscillator 1) shown in FIG. 1 can be obtained.

Further, the extended portion 4a may be folded back along the cutting line CL2 without being separated and inserted into the gap between the electronic component 6 and the package 3 or other gaps. As a result, the extended portion 4 a can be stored between the electronic component 6 and the package 3. As a result, the piezoelectric oscillator 1 incorporating the adjustment terminal 47 is obtained.
In such a piezoelectric oscillator 1, various information in the electronic component 6 can be rewritten as needed by pulling the extended portion 4 a out of the gap as necessary. Thereby, even if the usage environment of the piezoelectric oscillator 1 changes significantly after the manufacture of the piezoelectric oscillator 1, the piezoelectric oscillator 1 capable of stable oscillation by rewriting various information corresponding to the usage environment in the electronic component 6. Is obtained.

The piezoelectric oscillator 1 as described above can be applied to various electronic devices, and the obtained electronic device has high reliability.
The electronic apparatus provided with the piezoelectric device of the present invention is not particularly limited. For example, a personal computer (mobile personal computer), a mobile phone, a digital still camera, an ink jet type ejection device (for example, an ink jet printer), and a laptop personal computer. , TV, video camera, video tape recorder, car navigation device, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game device, word processor, workstation, video phone, security TV monitor, electronic binoculars POS terminal, medical equipment (eg electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring equipment, instruments (eg, vehicle, aircraft, ship) Instrumentation), hula Simulator, and the like.

Although the piezoelectric device and the method for manufacturing the piezoelectric device of the present invention have been described based on the illustrated embodiments, the present invention is not limited to these.
For example, each fold 401 may be a curved “fold” without a clear fold line, rather than a “fold” with fold lines 402a, 402b.
In addition, the piezoelectric device of the present invention includes a crystal oscillator (SPXO), a voltage controlled crystal oscillator (VCXO), a temperature compensated crystal oscillator (TCXO), a crystal oscillator with a thermostatic chamber (OCXO), a gyro sensor, an elasticity It is applied to surface wave (SAW) filters.

  DESCRIPTION OF SYMBOLS 1 ... Piezoelectric oscillator 2 ... Piezoelectric vibration piece 21 ... Piezoelectric substrate 3 ... Package 31 ... Base substrate 32 ... Lid member 34 ... Mount electrode 35 ... External terminal 39 ... Conductive adhesive 4 ... ... Mounting board 4a ... Expansion part 4b ... Blank part 40 ... Insulating board 401 ... Bending part 401a ... Inclined part 401b ... Tip part 402a, 402b ... Bending line 404 ... Incision 41 ... Electrode Terminal part 42 ... Wiring pattern 43, 43a, 43b, 43c ... Mounting terminal 44 ... Bump 45 ... Conductor post 46 ... Wiring pattern 47 ... Adjustment terminal 48 ... Connection pattern 51 ... Jig 52 ... Mold 53 ... Pedestal 54 ... Probe 6 ... Electronic parts 61 ... Pad part 7 ... Mold resin 8 ... Circuit board 81, 82 ... Circuit wiring 9 ... Gap 91, 91a, 91b, 91c ... Connection part 92 ... Fillet 93 ... Spacer 100 ... Mounting board film 400 ... Temporary board 900 ... Piezoelectric oscillator 901 ... Mounting board 902 ... ... Electronic components 903 ... Package 910 ... Notch 911 ... Bending part 912 ... Mounting terminal 913 ... Underfill material 920 ... Circuit board 921 ... Insulating board 922 ... Circuit wiring 923 ... Solder layer S1 Internal space BH Bonding head CL, CL2 Cutting line L1, L2 Length

Claims (8)

A mounting substrate, a package provided on one surface side of the mounting substrate and containing the piezoelectric vibrating piece, and provided between the mounting substrate and the package, for driving the piezoelectric vibrating piece A method of manufacturing a piezoelectric device having an electronic component,
Preparing a mounting substrate film in which a plurality of regions to be the mounting substrate are connected, and placing each electronic component on one surface side of each region;
A package mounting step of stacking and mounting the packages so as to sandwich the electronic components with respect to the mounting substrate film;
A folding step of bending a whole pair of opposing edges of the region to the package side to form a bent portion, and fixing a part of the bent portion to the package;
A resin filling step of filling a resin between the mounting substrate film and the package and covering the electronic component with the resin;
A method of manufacturing a piezoelectric device, comprising: a cutting step of cutting a boundary between the regions of the mounting substrate film into a plurality of the piezoelectric devices.   The method for manufacturing a piezoelectric device according to claim 1, wherein the package mounting step includes a step of bonding the package to each electronic component with an adhesive. The mounting substrate film has a region to be the mounting substrate, and an extended portion that is connected to the region and includes an adjustment terminal that is electrically connected to the electronic component in the electronic component mounting step. And
3. The method of manufacturing a piezoelectric device according to claim 1, further comprising an adjustment step of rewriting information on the electronic component via the adjustment terminal and then separating the region and the extended portion after the package placement step. Method. A mounting board; and
A package provided on one side of the mounting substrate and containing a piezoelectric vibrating piece;
An electronic component provided between the mounting substrate and the package for driving the piezoelectric vibrating piece;
The mounting substrate has a bent portion formed by bending the entire pair of opposing edges to the package side,
A part of the bent portion is fixed to the package;
A piezoelectric device, wherein a resin is filled between the mounting substrate and the package, and the electronic component is covered with the resin.   The piezoelectric device according to claim 4, further comprising a mounting terminal provided on a surface of the bent portion opposite to the package. The bent portion includes an inclined portion that is inclined with respect to the electronic component mounting portion on which the electronic component of the mounting board is mounted, and a tip portion that is a portion extending from the inclined portion toward the outer edge side. ,
The piezoelectric device according to claim 5, wherein the tip portion is fixed to the package.   The piezoelectric device according to claim 6, wherein the mounting terminal is provided on the inclined portion.   The piezoelectric device according to claim 4, wherein the mounting substrate is made of a flexible material.

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