JP2005192179A - Piezoelectric oscillator, portable telephone apparatus using same, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric oscillator or the like which improves a joining strength of each terminal portion and can prevent an electric circuit from being short-circuited or disconnected even if the piezoelectric oscillator is small-sized. <P>SOLUTION: In the piezoelectric oscillator in which a first package 35 overlaps a second package 60, the second package comprises a connection terminal portion 41a formed by arranging a terminal portion of a first lead frame which is connected with an oscillation circuit element 61 by a conductor line 62, so as to face an external terminal portion 37, a mounting terminal portion 51a formed by arranging a terminal portion of a second lead frame to overlap the connection terminal portion 41a in a plane view, and an insulating member 64 which seals the whole, except for a mounting surface of the mounting terminal portion, to join the first package and the second package. The connection terminal portion 41a is configured to be connected with the external terminal portion by a fused conductive material 66, and includes a pool portion 46 where the conductive material is stored, in the area opposite to the side of the oscillation circuit element. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a piezoelectric oscillator in which a piezoelectric vibrating piece and an oscillation circuit element are built in a package, a cellular phone device using the same, and an electronic apparatus.

Piezoelectric oscillators are widely used in small information devices such as HDDs (hard disk drives), mobile computers, and IC cards, and mobile communication devices such as mobile phones, car phones, and paging systems.
11 and 12 are drawings of a conventional piezoelectric oscillator, FIG. 11 is a plan view in the middle of manufacturing, and FIG. 12 is a cross-sectional view taken along a line CC in FIG. 11 (for example, Patent Document 1). reference).

In the piezoelectric oscillator 100, the piezoelectric vibrator 102 is disposed on the lower side of the lead frame 120, and the oscillation circuit element 110 is disposed on the upper side, and these are sealed with a resin 101.
The lead frame 120 includes a single planar frame, a mounting terminal portion 122 for mounting on a mounting substrate, and a connection terminal portion 124 for electrically connecting the oscillation circuit element 110 and the piezoelectric vibrator 102. And to form.
The piezoelectric vibrator 102 houses a piezoelectric vibrating piece (not shown) in a cylinder 104, and an external terminal portion 106 that is electrically connected to an excitation electrode (not shown) provided on the piezoelectric vibrating piece is drawn out of the cylinder. ing. The external terminal portion 106 is electrically connected to the connection terminal portion 124.
As the oscillation circuit element 110, an integrated circuit element or the like constituting the oscillation circuit is used, and is arranged on the die pad 108 provided in the center portion. The oscillation circuit element 110 is electrically connected to the mounting terminal portion 122 and the connection terminal portion 124 by a bonding wire 130.

Japanese Utility Model Publication No. 5-16724

  By the way, in recent years, various electronic devices such as the above-described information devices and mobile communication devices are remarkably reduced in size and thickness, and the piezoelectric oscillators used for them are also required to be reduced in size and thickness. For this reason, the mounting terminal portion 122 and the connection terminal portion 124 are also downsized, and the bonding area of the mounting terminal portion 122 to the mounting substrate and the bonding area of the connection terminal portion 124 to the external terminal portion 106 are also reduced. Therefore, improving the bonding strength of the mounting terminal portion 122 and the connection terminal portion 124 is a major issue.

  However, in the conventional piezoelectric oscillator 100, since the lead frame 120 is planar as described above, the mounting terminal portion 122 and the connection terminal portion 124 are arranged side by side in the horizontal direction. For this reason, if the mounting terminal portion 122 and the connection terminal portion 124 are enlarged in order to increase the bonding strength, the size in the horizontal direction must be increased. Therefore, the structure of the conventional piezoelectric oscillator 100 has a limit in miniaturization. End up.

Therefore, the applicant of the present application has proposed an invention according to Japanese Patent Application No. 2003-334616.
FIG. 13 shows a longitudinal section of the piezoelectric oscillator 200 according to Japanese Patent Application No. 2003-334616.
The piezoelectric oscillator 200 includes a first package 210 and a second package 220. The first package 210 contains a piezoelectric vibrating piece 212 therein, and an excitation electrode (not shown) of the piezoelectric vibrating piece 212. ) And an external terminal portion 214 exposed to the outside. The second package 220 uses two lead frames arranged one above the other. The oscillation circuit element 222 is accommodated therein, and the oscillation circuit element 222 and the bonding wire 224 are electrically connected to each other. A connection terminal portion 226 and a mounting terminal portion 228 are connected.

Here, the second package 220 is formed in the following manner, and is arranged so that the connection terminal portion 226 and the mounting terminal portion 228 overlap each other in plan view.
That is, two lead frames of a first lead frame 234 and a second lead frame 235 are prepared, and an end portion of the first lead frame 234 is disposed so as to face the external terminal portion 214, thereby connecting terminal portions. The mounting terminal portion 228 is formed by arranging the end portion of the second lead frame 235 so as to overlap the connection terminal portion 226 when seen in a plan view.
Then, the solder 232 is disposed on the surface of the connection terminal portion 226 facing the external terminal portion 214, and the external terminal portion 214 is placed on the solder 232 so that the first package 210 is placed on the second package 220. Repeat.
Then, the solder 232 is melted in a reflow furnace or the like, the connection terminal portion 226 and the external terminal portion 214 are connected, and then the mounting surface of the mounting terminal portion 228 is left, and the oscillation circuit element 222 and the bonding wire 224 are left. The first package 210 and the second package 220 are joined and fixed by the insulating member 230 while the whole including the above is sealed with an insulating member 230 such as a resin.

  As described above, the piezoelectric oscillator 200 has two lead frames arranged one above the other so that the connection terminal portion 226 and the mounting terminal portion 228 overlap with each other when seen in a plan view. Even if the size in the horizontal direction is reduced, the area in the horizontal direction of the mounting terminal portion 228 and the connection terminal portion 226 can be increased. Therefore, even if the piezoelectric oscillator 200 is downsized, the bonding strength of the mounting terminal portion 228 to the mounting substrate and the bonding strength of the connection terminal portion 226 to the external terminal portion 214 can be improved.

However, in this piezoelectric oscillator 200, the connection terminal portion 226 and the external terminal portion 214 are connected to each other by the solder 232 so as to face each other, and the first package 210 and the second package 220 are joined. The oscillation circuit element 222, the bonding wire 224, and the like are sealed with the insulating member 230.
For this reason, when connecting the connection terminal portion 226 and the external terminal portion 214 with the solder 232, the oscillation circuit element 222 and the bonding wire 224 are not sealed. In such a state, when the molten solder 232 used to connect the connection terminal portion 226 and the external terminal portion 214 flows out to the oscillation circuit element 222 side, it adheres to the oscillation circuit element 222 through the bonding wire 224. The electric circuit may be short-circuited.
Further, if the molten solder 232 adheres to the bonding wire 224, there is a possibility that the bonding wire 224 may be cut when the solder 232 is cooled and solidified. The cutting of the bonding wire 224 when the solder 232 is cooled may occur when the piezoelectric oscillator 200 is placed in a reflow furnace and mounted on a mounting board.
On the other hand, in order to avoid such a short circuit and the cutting of the bonding wire 224, the amount of the solder 232 may be reduced. However, the amount of the solder 232 applied is originally minute with the miniaturization of the piezoelectric oscillator 200. Therefore, it is very difficult to control the coating amount. Moreover, if the application amount is reduced, it becomes impossible to ensure a predetermined bonding strength between the connection terminal portion 226 and the external terminal portion 214.

  The present invention is for solving the above-mentioned problems, and even if the piezoelectric oscillator is downsized, the piezoelectric oscillator capable of improving the bonding strength of each terminal portion and preventing a short circuit or disconnection of an electric circuit, It is another object of the present invention to provide a mobile phone and an electronic device using the same.

  According to the first aspect of the present invention, the piezoelectric resonator element is housed inside, and is electrically connected to the excitation electrode of the piezoelectric resonator element and has an external terminal portion exposed to the outside. A package and a second package that is electrically connected to the external terminal portion and accommodates an oscillation circuit element for configuring an oscillation circuit, and the first package is fixed to the second package by overlapping the second package In the piezoelectric oscillator, the second package includes first and second lead frames, and an end portion of the first lead frame connected to the oscillation circuit element by a conduction line is connected to the outside. A connection terminal portion formed so as to be opposed to the terminal portion and an end portion of the second lead frame electrically connected to the oscillation circuit element overlap with the connection terminal portion when seen in a plan view. Arrange so that A mounting terminal portion formed, and an insulating member that seals the entire mounting terminal portion except the mounting surface so that the first package and the second package are bonded to each other. The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a concave portion is formed in a region opposite to the oscillation circuit element side to collect the conductive material. This is achieved by a piezoelectric oscillator in which a reservoir is formed.

According to the configuration of the first invention, the second package of the piezoelectric oscillator includes the first and second lead frames, and is arranged so that the end portion of the first lead frame faces the external terminal portion. Thus, a connection terminal portion is formed, and an end portion of the second lead frame is arranged so as to overlap with the connection terminal portion in plan view, thereby forming a mounting terminal portion. For this reason, even if the horizontal size of the piezoelectric oscillator is reduced compared to the conventional case, it is not necessary to reduce the horizontal size of the connection terminal portion and the mounting terminal portion, and it is possible to ensure the necessary joint area. The joint strength in each terminal part can be improved.
The second package is configured such that the first package and the second package are joined by an insulating member such as a resin, for example, so that the whole of the mounting terminal portion except the mounting surface is sealed. ing. For this reason, the connection terminal portion and the mounting terminal portion formed by the first and second lead frames, the oscillation circuit element, and the like can be fixed, and at the time of fixing, the first package and the second package are joined. You can also. Therefore, it is not necessary to separately provide an adhesive for joining the first package and the second package. In addition, before the first package and the second package are bonded and fixed, the inspection on the first package side and the inspection on the second package side can be individually performed. Therefore, it is not necessary to discard the entire piezoelectric oscillator when only one of the piezoelectric vibrating piece and the oscillation circuit element is defective, and the manufacturing cost can be reduced.

Here, since the second package seals the whole of the mounting terminal portion except the mounting surface so that the first package and the second package are joined by the insulating member, the insulating member Before sealing with, it is necessary to connect the connection terminal portion and the external terminal portion with a molten conductive material such as solder. Then, when the conductive material is melted, the conductive line and the oscillation circuit element are not sealed. For this reason, when the molten conductive material flows out to the oscillation circuit element side, it adheres to unsealed conductive lines and oscillation circuit elements, and there is a possibility that an electrical circuit may be short-circuited or disconnected.
However, in the piezoelectric oscillator according to the present invention, a reservoir portion is formed in a region opposite to the oscillation circuit element side so that a conductive material is accumulated by forming a recess. For this reason, the molten conductive material can be prevented from flowing to the oscillation circuit side in an attempt to accumulate in the region opposite to the oscillation circuit element side where there is a recess. Thereby, it is possible to prevent the molten conductive material from adhering to unsealed conductive lines and oscillation circuit elements, and to prevent short circuit and disconnection of the electric circuit.
Therefore, according to the present invention, it is possible to provide a piezoelectric oscillator capable of improving the bonding strength of each terminal portion and preventing a short circuit or disconnection of an electric circuit even if the piezoelectric oscillator is downsized. .

According to a second aspect of the present invention, in the configuration of the first aspect, a side end surface of the external terminal portion is exposed on a side surface of the first package, and the reservoir portion is the side end surface of the external terminal portion. It is characterized by being extended outward.
According to the structure of 2nd invention, the reservoir part is extended | stretched outside from the side end surface of the external terminal part. Then, since the molten conductive material is accumulated in the reservoir portion, the molten conductive material is also accumulated outside the side end surface of the external terminal portion. And since the side terminal surface of the external terminal part is exposed to the side surface of the first package, the molten conductive material accumulated outside as described above is likely to adhere to the side end surface of the external terminal part. Therefore, a fillet can be reliably formed on the side surface of the external terminal portion, and the bonding strength between the connection terminal portion and the external terminal portion can be improved.

According to a third aspect of the invention, in the configuration of the second aspect of the invention, the reservoir portion is formed so as to have a step portion than the oscillation circuit element and not to have a step portion on the outside. And
According to the configuration of the third invention, since the reservoir portion has a step portion than the oscillation circuit element and does not have the step portion on the outside, it is possible to reliably prevent the molten conductive material from flowing inward. The molten conductive material tends to accumulate outside. Therefore, compared to the second invention, it is possible to more reliably prevent the molten conductive material from adhering to the conductive line and the oscillation circuit element, to prevent short circuit and disconnection of the conductive line, and more reliably to the external terminal portion. A fillet can be formed on the side surface.

According to a fourth invention, in any one of the first to third inventions, the reservoir portion has an inclined surface that descends toward the opposite side of the oscillation circuit element. .
According to the configuration of the fourth aspect of the invention, since the reservoir has an inclined surface that descends toward the opposite side of the oscillation circuit element, the molten conductive material easily flows to the opposite side of the oscillation circuit element. Become. Therefore, compared to the first to third inventions, it is possible to more effectively prevent the molten conductive material from adhering to the conductive line and the oscillation circuit element, and the molten conductive material can easily flow outside the external terminal portion. Thus, the fillet can be more reliably formed on the side surface of the external terminal portion.

According to a fifth invention, in any one of the first to fourth inventions, the reservoir is formed by pressing the first lead frame and partially reducing the thickness. Features.
According to the configuration of the fifth invention, the reservoir is formed by pressing the first lead frame and partially reducing the thickness. Therefore, the reservoir portion can be formed without changing the thickness of the connection terminal portion, and the height of the piezoelectric oscillator can be reduced.

According to a sixth invention, in any one of the first to fifth inventions, the connection terminal portion has a through-hole penetrating in the thickness direction.
According to the configuration of the sixth invention, since the connection terminal portion has a through-hole penetrating in the thickness direction, for example, even if the molten conductive material is pushed by the first package and flows to the oscillation circuit side, It is possible to prevent the conductive material from flowing into the through hole and flowing to the oscillation circuit side.

  According to the seventh aspect of the present invention, the piezoelectric resonator element is housed inside, and is electrically connected to the excitation electrode of the piezoelectric resonator element and has an external terminal portion exposed to the outside. 1 package and a second package that is electrically connected to the external terminal portion and accommodates an oscillation circuit element for constituting an oscillation circuit, and the first package is stacked on the second package. The second package includes first and second lead frames, and the first package is connected to the oscillation circuit element by a conductive line. A connection terminal portion formed by arranging an end portion of a lead frame so as to face the external terminal portion, and an end portion of the second lead frame electrically connected to the oscillation circuit element as the connection terminal Part and plane The mounting terminal part formed so as to be overlapped with each other and the first package and the second package are joined, and the whole except the mounting surface of the mounting terminal part is sealed The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a recess is formed in a region opposite to the oscillation circuit element side. This is achieved by a mobile phone device that obtains a clock signal for control by a piezoelectric oscillator in which a reservoir portion in which the conductive material is accumulated is formed.

  According to an eighth aspect of the present invention, the piezoelectric vibration piece is housed inside, and is electrically connected to the excitation electrode of the piezoelectric vibration piece and has an external terminal portion exposed to the outside. 1 package and a second package that is electrically connected to the external terminal portion and accommodates an oscillation circuit element for constituting an oscillation circuit, and the first package is stacked on the second package. The second package includes first and second lead frames, and the first lead connected to the oscillation circuit element through a conductive line. A connection terminal portion formed by disposing an end portion of the frame so as to face the external terminal portion, and an end portion of the second lead frame electrically connected to the oscillation circuit element as the connection terminal portion. And in plane The mounting terminal portion formed so as to be overlapped with each other, the first package, and the second package are joined, and the whole except the mounting surface of the mounting terminal portion is sealed. The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a recess is formed in a region opposite to the oscillation circuit element side. This is achieved by an electronic device in which a clock signal for control is obtained by a piezoelectric oscillator having a reservoir portion in which the conductive material is accumulated.

1 and 2 show a first embodiment of a piezoelectric oscillator according to the present invention, FIG. 1 is a schematic exploded perspective view thereof, FIG. 2A is a schematic sectional view taken along line AA in FIG. FIG. 2B is a partially enlarged sectional view in which the vicinity of the boundary between the first package and the second package is enlarged.
Note that the parallel diagonal lines (hatching) of the terminal portions in FIG. 2 are given for convenience of understanding, and do not indicate cut surfaces, but indicate positions in the vertical direction (vertical direction) of each terminal portion and the like. It is.
In the figure, a piezoelectric oscillator 30 includes a first package 35 that accommodates a piezoelectric vibrating piece 32 therein, and a second package 60 that is fixed on the first package 35 and that accommodates an oscillation circuit element described later. It has.

First, the structure of the first package 35 will be described.
As shown in FIG. 2, the first package 35 is formed by, for example, laminating a plurality of substrates 35a and 35b formed by molding an aluminum oxide ceramic green sheet as an insulating material, and then sintering. Has been. The substrate 35b is formed in a rectangular box shape having an open upper end so that a predetermined hole is formed on the inner side so as to have a predetermined inner space S2 on the inner side when stacked. The internal space S2 is a housing space for housing the piezoelectric vibrating piece 32.

Further, as shown in FIG. 1, in this embodiment, the first package 35 is formed on the surface of the substrate 35b so as to be exposed to the internal space S2 in the vicinity of the left end portion in the drawing in the internal space S2. For example, electrode portions 31 and 31 formed by nickel plating and gold plating are provided on tungsten metallization. The electrode portions 31 and 31 are electrically connected to a second package 60 described later, and supply a drive voltage to the piezoelectric vibrating piece 32.
That is, the conductive adhesives 33 and 33 are applied on the electrode portions 31 and 31, and the base portion 36 of the piezoelectric vibrating piece 32 is placed on the conductive adhesives 33 and 33. 33 and 33 are joined by being cured. In addition, as the conductive adhesives 33 and 33, a synthetic resin agent as an adhesive component that exhibits bonding strength can be used containing conductive particles such as silver fine particles. A system-based or polyimide-based conductive adhesive or the like can be used.

The electrode portions 31 and 31 are electrically connected to external terminal portions 37, 37, and 37 formed by, for example, nickel plating and gold plating on tungsten metallization. The external terminal portions 37 are exposed at the four corners of the bottom surface of the first package 35. In this embodiment, the side end surface 37a is formed on the side surface of the first package 35 as shown in FIG. It is formed to be exposed. The external terminal portions 37 are provided at the four corners of the bottom surface of the first package 35, but some of them are not shown in FIG. In addition, all the external terminal portions 37 may not be connected to the electrode portions 31 and 31.
Specifically, each electrode portion 31 and each external terminal portion 37 are conductive through-holes formed by using the metallization of the first package 35 or using tungsten metallization or the like before firing the substrate 35a. Are electrically connected. In the present embodiment, as shown in FIG. 1, each electrode portion 31 and each external terminal portion 37 are vertically formed on the surface of a castellation portion 35 c formed by ¼ circles formed at the four corners of the first package 35. They are connected by conductive patterns extending in the direction (not shown for simplicity). The castellation portion 35c is formed on the basis of castellation that is a circular through hole that serves as a guide formed at the intersection of cutting lines when a large number of substrates are cut from the green sheet when the first package 35 is manufactured. It is.

The piezoelectric vibrating piece 32 is formed of, for example, quartz, and a piezoelectric material such as lithium tantalate or lithium niobate can be used in addition to quartz. In the case of the present embodiment, the piezoelectric vibrating piece 32 has a particularly illustrated shape in order to form a small size and obtain necessary performance.
That is, the piezoelectric vibrating piece 32 has a base portion 36 fixed to the first package 35 side, and a pair of vibrating arms 34 that extend in parallel to be divided into two forks toward the right in the drawing with the base portion 36 as a base end. , 34, and a so-called tuning fork type piezoelectric vibrating piece having a whole shape like a tuning fork is used.
The piezoelectric vibrating piece 32 is not limited to such a tuning-fork type, and various piezoelectric vibrating pieces such as a so-called AT-cut vibrating piece obtained by cutting a piezoelectric material into a rectangle can be used. .

As shown in FIG. 2, the upper opening of the first package 35 is sealed by bonding a glass lid 39 using a brazing material 38 such as low melting point glass, for example.
The brazing material 38 and the lid 39 can be provided with a shielding effect by grounding the lid 39 by using a metal Fe—Ni—Co alloy or the like. In this case, it is necessary to electrically connect at least one of the external terminal portions 37 and the lid 39 and to be electrically connected to the ground of the second package 60.

Next, the second package 60 will be described.
As shown in FIG. 2, the second package 60 is a package in which an oscillation circuit element 61 is accommodated and sealed with an insulating member 64 such as a resin.
The oscillation circuit element 61 uses one or a plurality of integrated circuits or electronic components such as a capacitor, and includes at least a predetermined circuit structure for exciting the piezoelectric vibrating piece 32. Preferably, the oscillation circuit element 61 is a thermostat as a temperature detecting means. A sensor (not shown) is provided. As a result, a temperature-compensated vibration piece can be used as the piezoelectric vibration piece 32. As shown in FIG. 2, the oscillation circuit element 61 is fixed to a substantially rectangular element mounting portion 55 disposed near the center by die bonding or the like.

  As shown in FIG. 2, the oscillation circuit element 61 is electrically connected to the mounting terminal portions 51a, 52a, 53a, and 54a (see FIG. 1) by wire bonding using a conductive wire 62 such as an Au wire. . The mounting terminal portions 51a, 52a, 53a, and 54a are terminal portions when mounted on a mounting board or the like. In the present embodiment, the mounting terminal portions 51a, 52a, 53a, and 54a are located below the oscillation circuit element 61 so that the mounting surface is exposed. Thus, they are arranged at the four corners of the second package 60.

The oscillation circuit element 61 is also electrically connected to the connection terminal portions 41a, 42a, 43a, and 44a (see FIG. 1) by wire bonding using the conductive wires 62. The connection terminal portions 41a, 42a, 43a, and 44a are terminal portions for electrically connecting the first package 35 and the second package 60. In the case of the present embodiment, each of the connection terminal portions 41a, 42a, 43a, 44a is disposed at the four corners so as to face the respective external terminal portions 37 of the first package 35, and as shown in FIG. As illustrated, the external terminal portion 37 is disposed so as to extend outward from the side end surface 37a (left side in FIG. 2B).
Each of the connection terminal portions 41a, 42a, 43a, and 44a is connected to each external terminal portion 37 by applying a conductive material 66 that can be electrically and mechanically connected. Note that the conductive material 66 only needs to be electrically and mechanically connected, and solder or a conductive adhesive similar to the conductive adhesive 33 shown in FIG. 1 can be used. As described above, solder is used in consideration of wettability so that a fillet can be easily formed on the side end surface 37 a of the external terminal portion 37.

  Such connection terminal portions 41a, 42a, 43a, and 44a and mounting terminal portions 51a, 52a, 53a, and 54a partially or entirely overlap in plan view as shown in FIGS. Are arranged as follows. That is, in the second package 60, the connection terminal portions 41a, 42a, 43a, and 44a and the mounting terminal portions 51a, 52a, 53a, and 54a are formed using separate lead frames, and these lead frames are made of resin. By fixing with, etc., it is possible to arrange them in a plan view.

Specifically, the second package 60 is formed as follows so as to include the first and second lead frames.
FIG. 3 is a schematic perspective view for clarifying the structure relating to the vertical positions of the first and second lead frames. FIG. 4 is a plan view of the second lead frame 50 and shows a state in which each lead portion of the second lead frame 50 is connected by a rectangular frame portion F1 surrounding the periphery. FIG. 5 is a plan view of the first lead frame 40 and shows a state in which each lead portion of the first lead frame 40 is connected by a rectangular frame portion F2 surrounding the periphery.

As shown in these drawings, each of a plurality of end portions (portions indicated by parallel oblique lines in FIG. 5) of the first lead frame 40 is opposed to each external terminal portion 37 as shown in FIG. The connecting terminal portions 41a, 42a, 43a, and 44a are formed by bending into a predetermined shape. Further, each of a plurality of end portions (portions indicated by parallel oblique lines in FIG. 4) of the second lead frame 50 is planarly connected to each connection terminal portion 41a, 42a, 43a, 44a as shown in FIG. The mounting terminal portions 51a, 52a, 53a, 54a are formed by bending into a predetermined shape so as to overlap.
The first and second lead frames 40 and 50 are each made of a commonly used material, for example, an Fe alloy such as 42 alloy, or Cu such as Cu—Sn, Cu—Fe, Cu—Zn, or Cu—Ni. It is formed of an alloy or a ternary alloy obtained by adding a third element to these.

Then, as shown in FIG. 2, the oscillation circuit element 61 is fixed on the element mounting portion 55 formed by the second lead frame 50, and the oscillation circuit element 61 and the connection terminal portion 41a, 42a, 43a and 44a are electrically connected. The oscillation circuit element 61 and the mounting terminal portions 51a, 52a, 53a, 54a are also electrically connected by wire bonding.
Thereafter, a conductive material 66 (see FIG. 2) such as solder is applied to the surfaces of the connection terminal portions 41a, 42a, 43a, 44a facing the external terminal portions 37, and the external terminal portions are formed on the conductive material 66. The first package 35 is placed on top so that 37 is disposed. In such a state, the conductive material 66 is melted in a reflow furnace or the like (not shown), and the connection terminal portions 41a, 42a, 43a, 44a and the external terminal portions 37 are connected.

Next, with the first package 35 placed on the second package 60, the entire surface excluding the mounting surface of the mounting terminal portions 51a, 52a, 53a, 54a is injection-molded with an insulating member 64 such as an epoxy resin. . In the present embodiment, as shown in FIG. 2, the caster portions 35 c provided at the four corners of the first package 35 are also covered and molded with the insulating member 64. As a result, the oscillation circuit element 61 and the conducting wire 62 are sealed, and the positions of the connection terminal portions 41a, 42a, 43a, 44a and the mounting terminal portions 51a, 52a, 53a, 54a are fixed, and further, the first package 35 and the second package 60 are joined.
Then, after resin molding, the frame portion F1 is cut off at each cutting line C1, C1, C1, C1 shown in FIG. 4 of the second lead frame 50, and each of the first lead frames 40 shown in FIG. The frame part F2 is cut off at the positions of the cutting lines C2, C2, C2, and C2, and the second package 60 is completed.

Next, the first lead frame 40 and the second lead frame 50 will be described in more detail.
As shown in FIG. 3, the second lead frame 50 shown in FIG. 4 is positioned in the lower part of the second package 60 and is arranged at almost four corners. A two-lead portion 52, a third lead portion 53, and a fourth lead portion 54 are provided.
Each of the first lead portion 51, the second lead portion 52, the third lead portion 53, and the fourth lead portion 54 has an end portion having a relatively large area (a portion indicated by parallel diagonal lines) as described above. It becomes part 51a, 52a, 53a, 54a. That is, the first to fourth lead portions 51, 52, 53, and 54 are bent so as to be positioned downward in FIG. 3 (in a direction away from the first package 35 in FIG. 2). The end portions 51a, 52a, 53a, 54a serving as the terminal portions are formed to be horizontal at a position one step lower than the remaining portions. Further, the portions of the first lead portion 51, the second lead portion 52, the third lead portion 53, and the fourth lead portion 54 other than the end portions 51 a, 52 a, 53 a, 54 a shown in a narrow shape are the oscillation circuit element 61 and It becomes an internal terminal connected by the conduction line 62 (see FIG. 2).
Further, the second lead frame 50 is parallel to each other between the first lead portion 51 and the fourth lead portion 54 and between the second lead portion 52 and the third lead portion 53 in a thin rectangular shape. Control terminal leads 57, 57 and 56, 56 extending in a straight line. The control terminal leads 57, 57, 56, 56 are also electrically connected to the oscillation circuit element 61 (not shown) by wire bonding using conductive wires such as Au wires.

As shown in FIG. 3, the first lead frame 40 of FIG. 5 is located above the second package 60, and is disposed at substantially the four corners, the first lead portion 41, the second lead portion 42, and the third lead frame 40. A lead part 43 and a fourth lead part 44 are provided.
Each of the first lead portion 41, the second lead portion 42, the third lead portion 43, and the fourth lead portion 44 has an end portion having a relatively large area (a portion indicated by parallel oblique lines) as a connection terminal portion 41a, 42a, 43a, 44a. That is, the first to fourth lead portions 41, 42, 43, and 44 are bent so as to be positioned upward in FIG. 3 (in a direction approaching the second package 35 in FIG. 2), and the remaining portions. The connecting terminal portions 41a, 42a, 43a, and 44a are formed so as to be horizontal at a position higher than that of the external terminal portion 37 (see FIGS. 1 and 2).
Further, the first lead portion 41, the second lead portion 42, the third lead portion 43, and the fourth lead portion 44 of FIG. 5 are one step lower than the portions indicated by the parallel oblique lines that form the connection terminal portions 41a, 42a, 43a, and 44a. The portions indicated by the narrow shape (located on the lower side) at the positions become the internal terminals 41d, 42d, 43d, and 44d connected to the oscillation circuit element 61 by the conduction line 62 (see FIG. 2).

Here, reservoir portions 46 are formed in the connection terminal portions 41a, 42a, 43a, 44a formed by the end portions of the first to fourth lead portions 41, 42, 43, 44, respectively.
FIG. 6 is a view for explaining the reservoir portion 46 and is a schematic enlarged perspective view of the fourth lead portion 44. FIGS. 7A to 7D are diagrams for explaining each variation of the reservoir portion 46. The left column of each figure is a schematic plan view of the fourth lead portion 44, and the right column is a left column. It is a schematic plan view at the time of mounting the 1st package 35 on the 4th lead part 44 of a column.
Since the first to third lead portions 41, 42, 43 have a reservoir portion 46 that is substantially the same as the fourth lead portion 44, only the reservoir portion 46 formed in the fourth lead portion 44 will be described below. .

  The reservoir portion 46 is a means for preventing the conductive material 66 (see FIG. 2) melted when the connection terminal portion 44 a and the external terminal portion 37 are connected from adhering to the conductive line 62 and the oscillation circuit element 61. And provided in a region opposite to the oscillation circuit element 61. That is, the reservoir portion 46 is a relative position that is determined by the position where the oscillation circuit element 61 is disposed. In the present embodiment, the oscillation circuit element 61 is located on the center side of the connection terminal portion 44a. Therefore, the reservoir 46 is provided on the outside of the second package 60 as indicated by the parallel diagonal lines in FIGS. 6 and 7.

Further, as shown in FIG. 2B, the reservoir portion 46 is formed by providing a concave portion on the surface facing the external terminal portion 37 of the fourth lead portion 44, and this concave portion is formed by the external terminal portion 37. The side end surface 37a is extended outward. That is, the concave portion is not only the surface facing the external terminal portion 37, but also outside the side end surface 37a of the external terminal portion 37, as shown in the right column of FIG. 2B and FIGS. 7A to 7D. Is also provided.
Further, the reservoir 46 has a stepped portion 46a closer to the oscillation circuit element 61 (right side in FIG. 6). It is sufficient that the step portion 46 a is provided at least from the oscillation circuit element 61 (on the right side in FIG. 6), but a step portion may be provided at a location other than the oscillation circuit element 61. However, it is more preferable not to have a step on the side opposite to the oscillation circuit element 61 (left side in FIG. 6), and in this embodiment, the step 46a is formed only from the oscillation circuit element 61.
The recess that becomes the reservoir 46 is formed, for example, with a punch K, by crushing the outside of the end portion 44a of the fourth lead portion 44 to partially reduce the thickness and adjusting the shape.

  The area where the reservoir 46 is provided may be any of the areas indicated by the parallel diagonal lines in FIGS. 7A to 7D. In the present embodiment, the conductive line 62 is In the region indicated by the parallel diagonal lines in FIGS. 7B, 7C and 7D in which the stepped portion 46a is formed on the internal terminal 44d side because it is connected to the location of the internal terminal 44d of the 4-lead portion, the reservoir portion 46 is preferably provided.

  The present embodiment is configured as described above. A mounting board or the like (not shown) on which the piezoelectric oscillator 30 is mounted using the two lead frames of the first lead frame 40 and the second lead frame 50. Mounting terminal portions 51a, 52a, 53a, 54a that are means for connecting the second package 60 and the connection terminal portion 41a that is means for electrically connecting the second package 60 and the first package 35. , 42a, 43a, 44a can be formed at positions overlapping in the vertical direction as shown in FIGS. Therefore, even if the horizontal size of the piezoelectric oscillator is reduced as compared with the prior art, the horizontal sizes of the connection terminal portions 41a, 42a, 43a, 44a and the mounting terminal portions 51a, 52a, 53a, 54a need not be reduced. In addition, since a necessary bonding area can be ensured, the bonding strength at each terminal portion can be improved.

  Further, the second package 60 is mounted on the mounting terminal portions 51a, 52a, 53a, and 54a so that the first package 35 and the second package 60 are joined by an insulating member 64 such as a resin. The whole except the surface is sealed. For this reason, when fixing the connection terminal portions 41a, 42a, 43a, 44a and the mounting terminal portions 51a, 52a, 53a, 54a formed by the first and second lead frames 40, 50, the oscillation circuit element 61, and the like. The first package 35 and the second package 60 can also be joined. Therefore, it is not necessary to separately provide an adhesive for joining the first package 35 and the second package 60, and the manufacturing cost can be reduced.

  Further, as described above, when the connection terminal portions 41a, 42a, 43a, 44a and the external terminal portions 37 are connected by melting the conductive material 66 such as solder, the conductive wires 62 and the oscillation circuit element 61 are sealed. Although not provided, the connecting terminal portions 41a, 42a, 43a, 44a are provided with a reservoir 46 in a region opposite to the oscillation circuit element 61 side as shown in FIG. For this reason, the molten conductive material 66 is restrained from being accumulated in the reservoir 46 in the region opposite to the oscillation circuit element 61 side and flowing to the oscillation circuit element 61 side. Therefore, it is possible to prevent the conductive material 66 from adhering to the unsealed conductive line 62 and the oscillation circuit element 61, thereby preventing a short circuit or disconnection of the electric circuit.

Further, since the reservoir portion 46 extends outward from the side end surface 37 a of the external terminal portion 37, the molten conductive material 66 accumulates outside the side end surface 37 a of the external terminal portion, and the side surface of the first package 35 is accumulated. The conductive material 66 easily adheres to the side end surface 37a of the external terminal portion 37 exposed to the surface. Therefore, a fillet can be reliably formed on the side surface of the external terminal portion 37, and the bonding strength between the connection terminal portions 41a, 42a, 43a, 44a and each external terminal portion 37 can be improved.
Moreover, since the reservoir portion 46 has a step portion 46a more than the oscillation circuit element 61 and is formed with a concave portion that does not have a step portion on the outside, the molten conductive material 66 is more likely to accumulate outside, The fillet can be formed on the side surface of the external terminal portion 37 while preventing the electrical circuit from being short-circuited or disconnected.

  Further, since the reservoir portion 46 is formed by crushing the outside of the end portion of the first lead frame 40 and partially reducing the thickness, the connection terminal portion is formed in order to form the reservoir portion 46. It is not necessary to change the thickness of 41a, 42a, 43a, 44a in particular, and the piezoelectric oscillator 30 can be reduced in height.

FIG. 8 shows a modification of the first embodiment shown in FIGS. 1 to 7, in which FIG. 8 (a) is a schematic sectional view of the piezoelectric oscillator 70, and FIG. 8 (b) is a view of the vicinity of the connection terminal portion 41a. It is a partial enlarged view.
In this figure, the same reference numerals as those used in FIGS. 1 to 7 are the same in configuration, and therefore, overlapping description will be omitted, and differences will be mainly described. Further, since the connection terminal portion 41a and the other connection terminal portions 42a, 43a, 44a have substantially the same configuration, only the connection terminal portion 41a will be described below.

The connection terminal portion 41a is different from the first embodiment only in that the shape of the reservoir portion is different. That is, the reservoir 72 shown in FIG. 8 is different only in that the reservoir 72 has an inclined surface 72 a that descends toward the opposite side of the oscillation circuit element 61.
Therefore, when connecting the connection terminal portion 41a and the external terminal portion 37, the molten conductive material 66 is likely to flow in the direction opposite to the oscillation circuit element 61 side (left side in FIG. 8B).
Therefore, the same operation effect as the first embodiment is exhibited, and the molten conductive material 66 is more effectively prevented from adhering to the conductive line 62 and the oscillation circuit element 61 as compared with the first embodiment. In addition, the melted conductive material 66 can be easily flowed to the outside, and the fillet can be more reliably formed on the side end surface 37 a of the external terminal portion 37.

FIG. 9 shows a piezoelectric oscillator 80 according to the second embodiment of the present invention, in which FIG. 9A is a schematic sectional view of the piezoelectric oscillator 80, and FIG. 9B is a partially enlarged sectional view in the vicinity of the connection terminal portion 42a. FIG.
In this figure, the same reference numerals as those used in FIGS. 1 to 8 are the same in configuration, and therefore, overlapping description will be omitted, and differences will be mainly described.
The piezoelectric oscillator 80 is different from the first embodiment in the shape of the connection terminal portions 41a, 42a, 43a, 44a. Since the connection terminal portion 42a and the other connection terminal portions 41a, 43a, 44a have substantially the same configuration, only the connection terminal portion 42a will be described below.

That is, the connection terminal portion 42a has a through hole 82 that penetrates in the thickness direction.
Although the through hole 82 is formed in the reservoir portion 46 in FIG. 9, it may be provided at any position as long as it is the connection terminal portion 42a. For example, the through hole 82 is provided inside the step portion 46a (on the oscillation circuit element 61 side). It does not matter. Further, only one through hole 82 is provided in the connection terminal portion 42a, but a plurality of through holes 82 may be provided.
In FIG. 9, the conductive material 66 such as solder is filled in the inner surface of the through hole 82 and further spreads around the back surface 42 b of the connection terminal portion 42 a.

  The second embodiment of the present invention is configured as described above, and thus exhibits the same effects as the first embodiment. Furthermore, since the connection terminal portion 42a has the through hole 82 penetrating in the thickness direction, the molten conductive material 66 can be prevented from flowing into the through hole 82 and flowing to the oscillation circuit element 61 side. That is, since it is difficult to control the application amount of the conductive material 66 on each connection terminal portion 41a, 42a, 43a, 44a, the application amount to each connection terminal portion 41a, 42a, 43a, 44a differs. For example, the first package 35 is inclined and placed as shown in FIG. Then, the molten conductive material 66 is pushed inward (oscillation circuit element 61 side) on the back surface of the first package 35 and tends to flow toward the oscillation circuit element 61 side. However, since the connection terminal portion 42a has the through hole 82 in the thickness direction, the molten conductive material 66 flows into the through hole 82 and flows to the oscillation circuit element 61 side even when pushed by the first package 35. Can be suppressed.

FIG. 10 is a diagram showing a schematic configuration of a digital mobile phone device as an example of an electronic apparatus using the piezoelectric oscillator according to the above-described embodiment of the present invention.
In the figure, the voice of a sender converted into an electrical signal by a microphone 308 is digitally modulated by a demodulator and a codec unit, frequency-converted to an RF (Radio Frequency) band by a transmission unit 307, and then transmitted through a base station (not shown). Sent). The RF signal from the base station is converted in frequency by the receiving unit 306, converted into an audio signal by the demodulator / codec unit, and output from the speaker 309. A CPU (Central Processing Unit) 301 controls the overall operation of the digital cellular phone device 300 including an input / output unit 302 including a liquid crystal display device and a keyboard. A memory 303 is an information storage unit including a RAM and a ROM, which is controlled by the CPU 301, and stores information such as a control program for the digital cellular phone device 300 and a telephone directory.

  As an example to which the piezoelectric oscillator according to the embodiment of the present invention is applied, there is a TCXO (Temperature Compensated X'stal Oscillator) 305, for example. The TCXO 305 is a piezoelectric oscillator in which frequency fluctuation due to ambient temperature change is reduced, and is widely used in mobile phone devices as a frequency reference source for the receiving unit 306 and the transmitting unit 307 in FIG. As the TCXO 305 has been downsized in recent years, the demand for downsizing has increased, and the TCXO downsizing by the structure according to the embodiment of the present invention is extremely useful.

  As described above, by using the piezoelectric oscillator 30 or the piezoelectric oscillator 70 according to the above-described embodiment in an electronic apparatus such as the digital cellular phone device 300, the mounting area in the horizontal direction can be reduced without increasing the mounting area. It is possible to improve the bonding strength and prevent an electrical circuit from being short-circuited or disconnected, and to obtain a digital cellular phone device 300 with excellent quality.

The present invention is not limited to the above-described embodiment. Each configuration of each embodiment and each modification may be combined or omitted as appropriate, and may be combined with other configurations not shown.
In the embodiment described above, two lead frames are used when forming the first package, but three or more lead frames may be used. Further, the number and shape of terminals formed from each lead frame are not limited to the description of the embodiment, and can be determined as appropriate.

1 is a schematic exploded perspective view showing an embodiment of a piezoelectric oscillator of the present invention. 1A is a schematic cross-sectional view taken along the line AA of the piezoelectric oscillator of FIG. 1, and FIG. 2B is a partially enlarged cross-sectional view in which the vicinity of the boundary between the first package and the second package of FIG. The schematic perspective view which shows the bending structure of the 1st lead frame and 2nd lead frame utilized for the 2nd package of the piezoelectric oscillator of FIG. FIG. 3 is a schematic plan view showing an example of a second lead frame used for the second package of the piezoelectric oscillator of FIG. 1. FIG. 3 is a schematic plan view showing an example of a first lead frame used for a second package of the piezoelectric oscillator of FIG. 1. It is a figure for demonstrating a reservoir part, and a schematic expansion perspective view of a 4th lead part. It is a figure for demonstrating each variation of a reservoir part, The left column is a schematic plan view of a 4th lead part, The right column is a schematic plan view at the time of mounting a 1st package in the 4th lead part of a left column . (A) is a schematic sectional drawing which shows the modification of the piezoelectric oscillator of FIG. 2, (b) is the partial expanded sectional view which expanded the boundary vicinity of the 1st package of (a), and a 2nd package. It is a piezoelectric oscillator which concerns on the 2nd Embodiment of this invention, Comprising: (a) is the schematic sectional drawing, (b) is an expanded sectional view of a connection terminal part vicinity. 1 is a diagram showing a schematic configuration of a digital mobile phone device as an example of an electronic apparatus using a piezoelectric oscillator according to an embodiment of the present invention. The top view in the middle of manufacture about the conventional piezoelectric oscillator. Sectional drawing in the part corresponded to the CC line | wire of FIG. The longitudinal section of the piezoelectric oscillator concerning patent application 2003-334616 which the present applicant has proposed.

Explanation of symbols

  30, 70 ... piezoelectric oscillator, 32 ... piezoelectric vibrating piece, 35 ... first package, 37 ... external terminal portion, 40 ... first lead frame, 41a, 42a, 43a, 44a ... connection terminal part, 46 ... reservoir part, 50 ... second lead frame, 51a, 52a, 53a, 54a ... mounting terminal part, 60 ... second package, 61. ..Oscillator circuit element, 62... Conductive wire, 64 .. insulating member, 66.

Claims (8)

A piezoelectric vibrating piece is housed inside, and is electrically connected to the excitation electrode of the piezoelectric vibrating piece, and has a first package having an external terminal exposed to the outside, and is electrically connected to the external terminal. And a second package containing an oscillation circuit element for constituting an oscillation circuit, and a piezoelectric oscillator in which the first package is overlaid and fixed to the second package,
The second package is:
Including first and second lead frames;
A connection terminal portion formed by disposing an end portion of the first lead frame connected to the oscillation circuit element by a conduction line so as to face the external terminal portion;
A mounting terminal portion formed by disposing an end portion of the second lead frame electrically connected to the oscillation circuit element so as to overlap the connection terminal portion in plan view;
An insulating member that seals the whole of the mounting terminal portion except for the mounting surface so that the first package and the second package are joined;
With
The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a concave portion is formed in a region opposite to the oscillation circuit element side to collect the conductive material. A piezoelectric oscillator characterized in that a reservoir is formed.   The external terminal portion has a side end surface exposed at a side surface of the first package, and the reservoir portion extends outward from the side end surface of the external terminal portion. The piezoelectric oscillator according to 1.   3. The piezoelectric oscillator according to claim 2, wherein the reservoir portion is formed so as to have a step portion from the oscillation circuit element and not to have a step portion on the outside.   4. The piezoelectric oscillator according to claim 1, wherein the reservoir has an inclined surface that descends toward the opposite side of the oscillation circuit element.   5. The piezoelectric oscillator according to claim 1, wherein the reservoir portion is formed by pressing the first lead frame to partially reduce a thickness. 6. .   The piezoelectric oscillator according to claim 1, wherein the connection terminal portion has a through-hole penetrating in a thickness direction. A piezoelectric vibrating piece is housed inside, and is electrically connected to the excitation electrode of the piezoelectric vibrating piece, and has a first package having an external terminal exposed to the outside, and is electrically connected to the external terminal. And a second package containing an oscillation circuit element for constituting an oscillation circuit, and a cellular phone device using a piezoelectric oscillator in which the first package is stacked and fixed on the second package,
The second package is:
Including first and second lead frames;
A connection terminal portion formed by disposing an end portion of the first lead frame connected to the oscillation circuit element by a conduction line so as to face the external terminal portion;
A mounting terminal portion formed by disposing an end portion of the second lead frame electrically connected to the oscillation circuit element so as to overlap the connection terminal portion in plan view;
An insulating member that seals the whole of the mounting terminal portion except for the mounting surface so that the first package and the second package are joined;
With
The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a concave portion is formed in a region opposite to the oscillation circuit element side to collect the conductive material. A cellular phone device characterized in that a control clock signal is obtained by a piezoelectric oscillator in which a reservoir is formed. A piezoelectric vibrating piece is housed inside, and is electrically connected to the excitation electrode of the piezoelectric vibrating piece, and has a first package having an external terminal exposed to the outside, and is electrically connected to the external terminal. A second package containing an oscillation circuit element for constituting an oscillation circuit, and an electronic device using a piezoelectric oscillator in which the first package is stacked and fixed on the second package,
The second package is:
Including first and second lead frames;
A connection terminal portion formed by disposing an end portion of the first lead frame connected to the oscillation circuit element by a conduction line so as to face the external terminal portion;
A mounting terminal portion formed by disposing an end portion of the second lead frame electrically connected to the oscillation circuit element so as to overlap the connection terminal portion in plan view;
An insulating member that seals the whole of the mounting terminal portion except for the mounting surface so that the first package and the second package are joined;
With
The connection terminal portion is connected to the external terminal portion by a molten conductive material, and a concave portion is formed in a region opposite to the oscillation circuit element side to collect the conductive material. An electronic device characterized in that a control clock signal is obtained by a piezoelectric oscillator in which a reservoir is formed.

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