JPS63250207A - Manufacture of surface wave equipment - Google Patents

Abstract

PURPOSE:To prevent the characteristic variation by connecting a lead frame and a surface wave element, after an insulating resin is coated to a surface wave element, bending a shield terminal to the rear surface side of a shield terminal and coating the conductive resin to the outer circumference of the insulating resin. CONSTITUTION:After an insulating resin 5 is coated to a surface wave element 1 to connect a lead frame 2, until the interval dimension of the tip of a shield terminal 4 and the insulating resin 5 comes to be the 1/2 or below of the interval dimension of the base end of the shield terminal 4 and the insulating resin 5, a shield terminal 5 is bent to the rear surface side of the surface wave element 1 and the tip of the shield terminal 4 is made into approximately the adhesion condition to the insulating resin 5 while a spring characteristic is held. By coating a conductive resin 7 to the outer circumference of the insulating resin 5 while the shield terminal 4 is included, the shield terminal 4 is buried to the conductive resin 7, the shield terminal 4 is not separated from the insulating resin 7 and connected through the conductive resin 7 without fail. Thus, the shieldability is improved and a stable characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a surface wave device, and particularly to a method for manufacturing a resin-dipped surface wave device.

Conventionally, in a resin-dipped surface acoustic wave device, the lead frame has a linear shield terminal portion 50 formed approximately in the center thereof, and the shield terminal portion 50 has A lead terminal portion 52 consisting of an appropriate number of five lead terminals was formed on both the left and right sides.

In a resin-dipped surface acoustic wave device having such a lead frame, a surface acoustic wave element (not shown) is first connected to the lead terminal section 52, and then the shield terminal section 50 is connected to the back surface of the surface acoustic wave element. It was manufactured by connecting to the formed shield electrode and then dipping the surface acoustic wave element with an insulating resin.

However, since the above insulating resin does not have a shielding function,
The surface acoustic wave device manufactured as described above has a problem in that the surface side of the surface acoustic wave element is not shielded, and characteristics change due to influences from the surroundings.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a surface acoustic wave device that can improve shielding performance and obtain stable characteristics by solving these conventional problems.

Hiroshi Tako @ MV r t 4; Δf role In order to achieve the above object, the method for manufacturing a surface acoustic wave device of the present invention comprises a lead terminal portion and a shield terminal portion, and the shield terminal portion is divided into two. A lead frame with one end as a ground terminal and the other as a shield terminal is provided, the lead frame and the surface wave element are connected, and then an insulating resin is applied to the surface wave element, and then the tip of the shield terminal and the other end are connected. Bend the shield terminal toward the back side of the surface wave element until the gap between the shield terminal and the insulating resin becomes 172 cm or less of the gap between the proximal end of the shield terminal and the insulating resin, and then fold the shield terminal. The gist is that a conductive resin is applied to the outer periphery of the insulating resin while containing the insulating resin.

According to the above manufacturing method, an insulating resin is applied to the surface wave element connected to the lead frame, and then the gap between the tip of the shield terminal and the insulating resin is adjusted to the base of the shield terminal. By bending the shield terminal toward the back side of the surface wave element until the gap between the end and the insulating resin becomes 1/2 or less, the tip of the shield terminal has a spring property and is almost bonded to the insulating resin. It is considered to be in close contact. Then, by applying a conductive resin to the outer periphery of the insulating resin while including the shield terminal, the shield terminal is embedded in the conductive resin, and the shield terminal is covered with the conductive resin without separating from the insulating resin. It is possible to manufacture a surface acoustic wave device with excellent shielding properties, which is reliably connected through the .

FIG. 1 is a developed view of a lead frame 2 used in the manufacturing method of the present invention, which includes a lead terminal portion 3 and a shield terminal portion 4. As shown in FIG. Further, the shield terminal portion 4 is formed with a U-shaped elongated hole 4c so that one side can be separated into a ground terminal 4a and the other side can be separated into a shield terminal 4b. Further, the lead terminal portions 3 are provided on both sides of the shield terminal portion 4. In this embodiment, the lead terminal section 3 is composed of four lead terminals 3a, . The terminals 3b and 3d are arranged so as to be connectable to the output side lead-out electrode.

Hereinafter, a method for manufacturing a surface acoustic wave device according to the present invention will be explained in detail based on FIGS. 2 to 6B.

First, as shown in FIG. 2, the surface wave element 1 and the lead frame 2 are connected by sandwiching the surface wave element 1 between the base ends 4d of the shield terminal portions 4.

Then, the tips of the lead terminal parts 3a and 3c are soldered to the input side extraction electrodes of the surface wave element 1, and the lead terminal parts 3b and 3d are soldered.
Connect the tip to the output side extraction electrode of the surface wave element l by soldering.

In this embodiment, a filter element is used as the surface wave element 1. Specifically, the filter element has an input-side interdigital transducer (hereinafter abbreviated as rI DTJ) and an output-side IDT arranged on a piezoelectric substrate, and when a signal voltage is applied to the input-side IDT, a signal is generated on the piezoelectric substrate. A surface wave is generated, which is converted back into an electrical signal at the output side IDT, and is configured to pass a desired band frequency by utilizing the conversion characteristics at that time. In the surface wave element, an input side lead-out electrode is formed at one end thereof, and an output side lead-out electrode is formed at the other end thereof.

Therefore, in this way, the surface wave element 1 and the lead frame 2
After connecting them, as shown in FIGS. 3A and 3B, an insulating resin 5 such as epoxy resin is applied to the outer periphery of the surface acoustic wave element 1. This insulating resin 5 is applied by a dipping method, and in order to obtain a vibration permissible space for the surface wave element 1, the resin is dipped with a cavity 6 formed. The method for forming the cavity 6 is to apply wax to the surface of the surface wave element 1, apply a thermosetting resin thereon, and bake the wax to absorb the wax into the resin, thereby forming the cavity. This can be carried out by any method such as a method or a method of covering the surface of the surface wave element 1 with a cap.

Next, the tip 4f of the shield terminal portion 4 is cut from the main portion 2a of the lead frame 2 to form a ground terminal 4a and a shield terminal 4b.

Thereafter, as shown in FIGS. 4A and 4B, the gap T between the tip 4f of the shield terminal 4b and the main insulating resin 5 is equal to the distance between the proximal end of the shield terminal 4b and the insulating resin 5.
The shield terminal 4b is bent toward the back side of the surface acoustic wave element 1 until the gap becomes 1/2 or less of the gap T' between the shield terminal 4b and the shield terminal 4b by the dipping method, as shown in FIGS. 5A and 5B. The conductive resin 7 is applied to the outer periphery of the insulating resin 5 in a state containing the above. That is, T<
By setting the shield terminal 4b to 1/2T' and giving the shield terminal 4b a spring property, the shield terminal 4b and the insulating resin 5 are dipped into the conductive resin 7 so that the shield terminal 4b and the insulating resin 5 can be brought into close contact with each other. is manufactured so as to be completely embedded in the conductive resin 7. That is, T≧
In the case of 1/2T', as shown in Fig. 7, the shield terminal 4b is warped in the direction of arrow A, and the external shape becomes approximately Y-shaped.
Not only is it unsightly, but there is a risk that the conductive resin 7 will be separated at the portion B and the insulating resin 5 and the shield terminal 4b will be separated, which may cause a new problem of lack of reliability. The present invention also focuses on this point and aims to improve reliability.

Furthermore, since the insulating resin 5 is applied by a dipping method, there is a possibility that the film thickness may vary;
When set to <1/2T', as shown in FIG. 8, the shield terminal 4b has spring properties and even if the film thickness becomes thick, the shield terminal 4b and the insulating resin 5 are in close contact with each other, so that variations in the film thickness are reduced. It also has the effect of being able to absorb

Finally, as shown in FIGS. 6A and 6B, an insulating device is applied to the conductive resin 7 and the shield terminal portion 4 to complete the manufacture of the surface acoustic wave device.

The surface acoustic wave device formed in this way has a shield terminal 4b.
is embedded in the conductive resin 7, and substantially the entire surface wave element 1 is shielded, so that the shielding performance is improved and the intended purpose can be achieved. In addition, the tip of the shield terminal is bent to give it spring properties and is in close contact with the insulating resin, so the conductive resin 7 and the shield terminal 4b do not separate, making the shielding function reliable. Sexuality also improves. However, since the shield terminal portion 4 is divided into two to form the ground terminal and the shield terminal, the materials used for the lead frame 2 can be used efficiently and can be manufactured at low cost.

It goes without saying that the present invention is not limited to the above-mentioned embodiments, and can be similarly applied to surface wave elements other than filter elements, such as resonators. Core section 2 of lead frame 2 at tip 4f
The cutting from a may be performed before applying the insulating resin to the surface wave element l.

As detailed above, the method for manufacturing a surface acoustic wave device according to the present invention involves connecting a surface acoustic wave element to a lead frame, coating the surface acoustic wave element with an insulating resin, and then performing the above-mentioned process. Bend the shield terminal toward the back side of the surface wave element until the gap between the tip of the shield terminal and the insulating resin becomes 1/2 or less of the gap between the base end of the shield terminal and the insulating resin. After that, a conductive resin was applied to the outer periphery of the insulating resin including the shield terminal, so that the shield terminal was buried in the conductive resin in close contact with the insulating resin, and was insulated from the shield terminal. It is possible to manufacture a highly reliable surface acoustic wave device which is securely connected to the conductive member through the conductive member without being separated from the conductive member, and whose front and back surfaces are shielded. Therefore, the surface acoustic wave device manufactured in this way can prevent characteristic fluctuations and use terminal materials efficiently, so it can be manufactured at low cost and has the effect of improving productivity. There is.

[Brief explanation of the drawing]

FIG. 1 is a front view of a lead frame, FIGS. 2 to 6B are process diagrams showing an example of the method for manufacturing a surface acoustic wave device according to the present invention, and FIG. 2 is a front view of a lead frame and a surface acoustic wave element. Figure 3A is a perspective view showing the connected state, Figure 3A is a perspective view showing the state when the surface wave element is coated with insulating resin and the shield terminal part is cut from the lead frame, and Figure 3B is the same as Figure 3A. 4A is a perspective view showing the state when the shield terminal is bent toward the back side of the surface wave element, FIG. 4B is a sectional view of FIG. 4A, and FIG. FIG. 5B is a sectional view of FIG. 5A, FIG. 6A is a perspective view of the surface acoustic wave device manufactured by the manufacturing method of the present invention, and FIG. 6B is a perspective view showing the state when the resin is applied. 7 is a sectional view showing an example of a surface wave device manufactured by a manufacturing method other than the manufacturing method of the present invention, and FIG. 8 is a sectional view of another surface wave device manufactured by the manufacturing method of the present invention. A sectional view showing an example, and FIG. 9 is a front view of a conventional lead frame. 1...Surface wave element, 2...Lead frame, 3...
・Lead terminal part, 4... Shield terminal part, 4a...
Earth terminal, 4b... Shield terminal, 5... Insulating resin, 7... Conductive resin, T, T'... Gap dimension. 4f Figure 6B Figure 3A Figure 4A Figure 3B Figure 9

Claims (1)

[Claims] (1) Provide a lead frame consisting of a lead terminal portion and a shield terminal portion, and divide the shield terminal portion into two and use one side as a ground terminal and the other as a shield terminal, and connect the lead frame and the surface wave element. After connecting and then applying an insulating resin to the surface wave element, the gap between the tip of the shield terminal and the insulating resin is 1 of the gap between the proximal end of the shield terminal and the insulating resin. /2 or less, the shield terminal is bent toward the back side of the surface wave element, and then a conductive resin is applied to the outer periphery of the insulating resin while including the shield terminal. Method of manufacturing the device.