JPH0964579A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electronic device in which the damage at the time of bending and the insufficient contact due to spring back can be prevented while eliminating the need of a step for shaping, e.g. the step for bending an earth terminal in order to conduct the shield part and the earth terminal, and simplifying the production process. SOLUTION: A board 14 on which a circuit element is formed is coated with a composite film 16 of an insulating resin film 16a and a conductive film 16b. The conductive film 16b on the outer surface of composite film 16 and an earth terminal 13 connected with the board 14 are conducted by inserting a conductor 17 into a through hole 19 made through the composite film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component having a transducer electrode portion such as an oscillator, a filter and a sensor, or a semiconductor electronic component which dislikes stray capacitance, a high frequency electronic component and the like, and particularly to an exterior portion. The present invention relates to improvement of a connection structure between a shield terminal and a shield terminal in a structure provided with an electromagnetic shield section.

[0002]

2. Description of the Related Art As an example of conventional electronic components, the structure of a resin-coated SAW (surface acoustic wave) filter is shown in FIGS.
Shown in FIG. 9 is a perspective view of an external structure of the conventional SAW filter 1, and FIG. 10 is a cross-sectional structure view from a direction along a section XX. The SAW filter 1 includes an element substrate 5 and
The input terminals 2a, which are respectively pulled out from the element substrate 5,
2b, output terminals 3a and 3b, and a ground terminal 4 are provided, and the periphery of the element substrate 5 is covered and sealed by an exterior resin portion 6.

A pair of interdigital transducers (IDTs) are formed on the SAW filter element substrate 5 at regular intervals, and the vicinity of the region sandwiched by the pair of IDTs constitutes a transducer section. In this portion, the surface wave propagates on the substrate surface from one IDT side to the other IDT side. Therefore, in the packaged state, the transducer part is manufactured so as to form an air gap between itself and the exterior part.

The exterior resin portion 6 is composed of an insulating resin 6a, a conductive film 6b and an exterior insulating film 6c. The conductive film 6b is a conductive layer for high frequency shielding,
Part of it is electrically connected to the ground terminal 4.

The SAW filter 1 as described above is manufactured as follows. First, with the input terminals 2a and 2b, the output terminals 3a and 3b, and the ground terminal 4 connected to the element substrate 5, wax is applied to the surface of the IDT transducer portion of the element substrate 5 to make the entire element substrate 5 porous. Dip in a thermosetting resin and dry. Next, a baking process is performed with the thermosetting resin coated.
When this baking process is performed, the wax enclosed in the thermosetting resin is melted and absorbed in the cured thermosetting resin, or evaporated to the outside, and the wax is applied to the transducer section of the IDT. A void is formed on the surface of the.

Further, a part of the ground terminal 4 is bent and brought into contact with the surface side of the insulating film 6a of thermosetting resin. Then, a part of the tip of the bent ground terminal and almost the entire surface of the insulating film 6a are immersed in a solution of a conductive paint, which is dried and baked to form a conductive film 6b on the surface of the insulating film 6a. Together with this conductive film 6b
And the bent portion of the ground terminal 4 are connected.

Further, an insulating resin is formed on the conductive film 6b to form the exterior insulating film 6c. Through these steps, the resin-coated SAW filter 1 is completed with the voids 9 formed on the surface of the transducer section of the IDT.

[0008]

However, in the conventional SAW filter 1 having the conductive film 6b for high-frequency shield, a part of the ground terminal 4 is bent in order to obtain conduction between the conductive film 6b and the ground terminal 4. A process is required, and this process requires machining, which complicates the process. Further, the material cost of the conductive paint used for the conductive film 6b is expensive, and there is also a problem that the manufacturing cost becomes high. Further, since springback occurs in the bent portion of the ground terminal 4, contact between the conductive film 6b and the bent portion of the ground terminal 4 becomes unstable.

Therefore, it is an object of the present invention to provide an electronic component having a connection structure capable of electrically connecting the shield portion and the ground terminal by a simpler method.

[0010]

An electronic component according to the present invention has an electronic component element body having a portion that should be functionally kept in a state where it can freely vibrate, and an electronic component substrate that is drawn outward from a substrate. It has a ground terminal, an insulating resin film, and a conductive film formed on one surface side of the insulating resin film, and is maintained in a state in which at least the electronic component body can freely vibrate. And a conductor-covered resin film that covers the periphery of the electronic component body such that a space is formed between the electronic component body and the insulating film. Through holes are formed in the conductor-coated resin film. And the electronic component is
A conductor that passes through the through hole formed in the conductor-covered resin film and electrically connects the conductive film of the conductor-covered resin film to the ground terminal is further provided.

Here, the electronic component body refers to a lead in various electronic components such as an oscillator, a filter, an electronic component having a transducer electrode portion such as a sensor, a semiconductor electronic component that dislikes stray capacitance, or a high frequency electronic component. It refers to the main part of the component in the state before the terminals and wiring are connected. Also, the conductor-coated resin film,
Resin film such as polypropylene, polyethylene, polyethylene terephthalate, aluminum, copper, silver,
Although it is composed of a two-layer film with a conductive film such as gold, it may be composed of three or more multilayer films in which a heat-resistant film or the like is further laminated.

Further, in a limited aspect of the present invention, the outer surface of the conductor-covered resin film and the conductor is covered with an insulating resin.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of an electronic component according to an embodiment of the present invention will be described below. 1 to 3 are views showing a structure of a SAW filter according to an embodiment of the present invention, FIG. 1 is a perspective view of an external structure thereof, and FIG. 2 is a cross-sectional structure view of a section YY in FIG. , FIG. 3 shows a SAW filter element 1
3 is a structural perspective view of FIG.

The SAW filter 10 includes a SAW filter element 14, input terminals 11a and 11b connected to the SAW filter element 14, output terminals 12a and 12b, a ground terminal 13, and a resin surrounding the SAW filter element 14. And a unit 20. The SAW filter element 14 has a pair of I on the surface of a piezoelectric substrate composed of a single crystal of lithium tantalate or PZT ceramics.
It has DTs 15a and 15b. Input IDT 15a
Is arranged such that a pair of comb-shaped electrodes mesh with each other, and the input terminals 11a and 11 are connected to the respective electrodes.
b is connected. Similarly, the output IDT 15b
Is arranged so that a pair of electrodes having a comb tooth shape mesh with each other, and each electrode has an output terminal 12a,
12b is connected. And this input and output ID
T15a and 15b and the substrate region located between them constitute a transducer section. In this area, input ID
The surface wave generated on the T15a side propagates toward the output IDT 15b side. Therefore, this transducer part
The surface acoustic waves need to be maintained in a state where they can freely vibrate and propagate without being fixed by the exterior resin portion 20.

The ground terminal 13 is connected to the back surface of the substrate of the SAW filter element 14. As shown in FIG. 2, the exterior resin portion 20 is composed of the composite film 16 and the exterior insulating film 18 formed on the outer surface thereof. The composite film 16 is made of PP (polypropylene), P
It is composed of a composite material in which a conductive film 16b made of aluminum, copper, silver, gold or the like is coated on the outer surface of a resin film 16a made of E (polyethylene), PET (polyethylene terephthalate) or the like. Since the composite film 16 has a certain degree of rigidity, when covering the periphery of the SAW filter element 14, it can be molded so as to form the void portion 21 on the surface of the transducer portion of the SAW filter element 14. . Further, the composite film 16 is provided with a through hole 19 at a position aligned with a part of the ground terminal 13. A conductor 17 made of a conductive material such as a conductive paste or solder is embedded in the through hole 19. The conductor 17 is connected to the surface of the ground terminal 13 and adhered to the surface of the conductive film 16b of the composite film 16. As a result, electrical conduction between the conductive film 16b and the ground terminal 13 is achieved.

On the surface of the composite film 16, an exterior insulating film 18 made of epoxy resin or the like is formed. Figure 4-
FIG. 8 is an explanatory view mainly for explaining a method of manufacturing the exterior resin part of the SAW filter 10.

First, as shown in FIG. 4, for example, a rectangular composite film 16 is prepared, and a through hole 19 is formed at a predetermined position. Next, as shown in FIG. 5, each terminal 11a, 11b, 12a, 12b, 13 is attached to the SAW filter element 14.
Is attached to the surface of the resin film 16a of the composite film 16 molded into a predetermined shape.
At this time, the through-hole 19 preformed in the composite film 16
And the ground terminal 13 is aligned so that a part of the ground terminal 13 is aligned.

Next, as shown in FIG. 6, the composite film 1
6 is folded in half, and the SAW filter element 14 is wrapped with the composite film 16. In this case, the periphery of the SAW filter element 14 is thermocompression-bonded by using a heat welding means such as a heat iron so as to seal the inside. Note that FIG. 6 shows an assembled state of the SAW filter element 14 and the composite film 16 in FIG. 5 as viewed from the back surface side in the drawing. Therefore, the through-hole 1 of the composite film 16
The state in which 9 reaches the surface of the ground terminal 13 is shown.

Further, as shown in FIG. 7, a conductive paste or solder is inserted into the through hole 19 to electrically connect the conductive film 16b of the composite film 16 and the ground terminal 13. It should be noted that FIG. 8 shows a cross-sectional structure from a direction along the cross section Z-Z in this state. As shown in FIG. 8, the conductor 17 is connected so as to electrically connect the conductive film 16 b and a part of the ground terminal 13 through the through hole 19.

After that, the SAW filter 10 is completed by forming the exterior insulating film 18 on the surface of the conductive film 16b. As described above, in the above-described embodiment, the ground terminal and the conductive film 16b for shielding the exterior resin portion are electrically connected by enclosing the conductor 17 in the through hole 19 formed in the composite film 16.

In the above embodiment, the composite film 16 is composed of the resin film 16a and the conductive film 16b.
Although the layer structure has been described, it may have a multilayer structure of two or more layers. That is, it is also possible to use a structure in which a heat insulating film is further mounted on the resin film and a conductive film is provided on the outer surface of this heat insulating film.

Further, in the above-mentioned embodiment, the conduction structure of the shield part of the SAW filter 10 has been described, but such a structure is not limited to the SAW filter but is widely applied to electronic parts having an electromagnetic shield part. Can be applied.

[0023]

As described above, the electronic component according to the present invention covers the substrate with the insulating resin film having the conductive film formed on the outer surface thereof, and is used as a shield through the through hole formed in a part thereof. Since the conductive film and the ground terminal are configured to be electrically conductive, the conductive film for shielding and the ground terminal can be electrically connected to each other without performing mechanical processing on the ground terminal. The manufacturing process of parts can be simplified. Furthermore, compared to the conventional example in which a part of the ground terminal is bent, the connection between the shield and the ground terminal is stabilized, improving the reliability of the conduction structure between the conductive film for shielding and the ground terminal. Can be made.

[Brief description of drawings]

FIG. 1 is a perspective view of an external structure of a SAW filter according to an embodiment of the present invention.

FIG. 2 is a cross-sectional structural view from a direction along YY in FIG.

3 is a structural perspective view showing the structure of a SAW filter element 14 shown in FIG.

FIG. 4 is a structural perspective view of a composite film 16 used in the SAW filter 10 of the present invention.

5 is an explanatory view showing one step of a manufacturing process of the SAW filter 10 shown in FIG. 1. FIG.

FIG. 6 is an explanatory view for explaining a manufacturing process subsequent to the manufacturing process shown in FIG.

FIG. 7 is an explanatory diagram for explaining a manufacturing process that follows the manufacturing process shown in FIG.

FIG. 8 is a sectional structural view from a direction along a section ZZ in FIG.

FIG. 9 is a structural perspective view of a conventional SAW filter.

FIG. 10 is a cross-sectional structural view from a direction along a cross section XX in FIG.

[Explanation of symbols]

 10 ... SAW filter 11a, 11b ... Input terminal 12a, 12b ... Output terminal 13 ... Ground terminal 14 ... SAW filter element 16 ... Composite film 16a ... Resin film 16b ... Conductive film 17 ... Conducting part 19 ... Through hole

Front page continued (72) Inventor Sadayuki Kato 2 26-10 Tenjin Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd. (72) Inventor Mitsuhiro Tada 2 26-10 Tenjin Tenjin, Nagaokakyo, Kyoto Murata Manufacturing Co., Ltd. (72) Inventor Yoshiaki Otani 2-26-10 Tenjin Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd. (72) Inventor Akira Imamura 2-26-10 Tenjin Tenjin, Nagaokakyo Kyoto Prefecture Murata Manufacturing Co., Ltd. (72) Invention Hitoshi Nishimura, 26-10 Tenjin, Tenjin, Nagaokakyo, Kyoto Prefecture, Murata Manufacturing Co., Ltd. (72) Yukio Hayashi, 2-10, Tenjin, Tenjin, Nagaokakyo, Kyoto Prefecture (72) Inventor, Ryosuke Sakai 2-26-10 Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd. (72) Kenji Fukushima Inventor, Kenji Fukushima 2-26-10 Tenjin, Nagaokakyo City, Kyoto Prefecture Murata Manufacturing Co., Ltd. (72) Toru Watanabe, Nagaokakyo, Kyoto Prefecture Tenjin 2 chome 26-10 Murata Manufacturing Co., Ltd.

Claims (2)

[Claims] 1. An electronic component body having a portion which is functionally capable of being freely vibrated, a ground terminal drawn outward from the substrate, and an insulating resin film, A conductive film formed on one surface side of the insulating resin film, and a space is formed between at least a portion of the electronic component element body to be maintained in a freely vibrable state. And a conductor-coated resin film that covers the periphery of the electronic component body so that the insulating resin film is on the inner side, the conductor-coated resin film has a through hole formed therein. And a conductor that passes through a through hole formed in the conductor-coated resin film and electrically connects the conductive film of the conductor-coated resin film and the ground terminal. , Electronic Goods. 2. The electronic component according to claim 1, wherein the outer surface of the conductor-covered resin film and the conductor is provided with an exterior containing an insulating resin.