JPS60180193A - Method of mounting terminal of electronic part - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to industrial applications such as semiconductor integrated circuits (
The present invention relates to a method for attaching a terminal of an electronic component, such as an IC, which is suitable for electrically connecting and mechanically fixing the terminal of an electronic component to a wiring board.

BACKGROUND TECHNOLOGY AND PROBLEMS Conventionally, for a large number of conductive patterns provided on a wiring board of an electronic device, such as a flexible board, or a rigid board, other conductive patterns corresponding to these conductive patterns and arranged in the same manner, such as a flexible board, have been provided. conductive pattern, I
2. Description of the Related Art A large number of conductors such as terminals of components such as C are electrically connected. This electrical connection is mainly made by soldering, but this soldering process is done by printing a resist for soldering in advance except for the parts to be soldered, or by laminating or pressing a coverlay film cut out with a die. This requires a complicated process of applying solder to the part to be soldered using a roll solder or the like, soldering it using a soldering iron or the like, and making an electrical connection, which is disadvantageous in that it is difficult to manufacture.

In view of this, electrical connection and mechanical fixing methods using adhesives as shown in FIGS. 1 and 2 have been proposed.

That is, in FIG. 1, (1) indicates a wiring board, and this wiring board (1) has a predetermined conductive pattern (2) on an insulating board.
was formed. A fibrous conductor (4) such as carbon fiber is mixed into an insulating adhesive (3) on this conductive pattern (2), and the fibrous conductor (4) is oriented almost in one direction. At the same time, an adhesive layer (5) made of a uniformly distributed adhesive layer (5) is applied so that the fibrous conductors (4) are insulated by the adhesive (3) so that they do not come into contact with each other. In this case the fibrous conductor (4) of the adhesive layer (5)
The direction of orientation of the conductive pattern (2) is made along the direction of extension of the conductive pattern (2). Moreover, the diameter of this fibrous conductor (4) is 0.5 μ to 50 μm.
μ, preferably 1 μ to 30 μ, and this fibrous conductor (
4) Length: 0.5μ to 3mm, preferably 1μ to 500mm
Let it be μ. Also, the fibrous conductor (4) in this adhesive (3)
The content is 1 to 50% by volume, preferably 5 to 40% by volume.
The thickness of the adhesive layer (5) to be applied is 5 to 200μ,
Preferably it is 10-100μ. The adhesive (3) used has an electrical resistance of 10 Ω/cm or more.

In this example, a wiring board (1
) and another wiring board (
When electrically connecting the force conductive pattern (8) and the conductive pattern (2), the conductive patterns (2) and (8) of the wiring boards (1) and (7) should face each other and overlap each other. Predetermined portions of the substrates (1) and (7) are superimposed on each other, and the superposed portion is pressurized and heated as shown by arrows a and b. In this way, as shown in FIG. 2, the adhesive layer (5) is pressed from both sides in the thickness direction between the conductive patterns (2) and (8) superimposed on each other. Since the conductive patterns (2
) and (8), mainly only the fibrous conductor (4) is sandwiched between these conductive patterns (2).
) and (8) in close contact along the mutually opposing surfaces. Then, by applying pressure in the thickness direction, the adhesive (
3) is a conductive pattern (2) and (8) for the part that is inserted between adjacent fibrous conductors (4).
However, the adhesive (3) other than this is extruded to the part where the conductive patterns (2) and (8) are not overlapped and fills the space between the side substrates (1) and (7) in this part. reach. In this way, an adhesive layer (5) is formed between the conductive patterns (2) and (8) which are superimposed on each other.
In the thickness direction, the fibrous conductor (4) is in contact with the conductive patterns (2) and (8) in a single layer or in multiple layers, and exhibits good electrical conductivity. Between the matching conductive turns (2) (2) and (8) (8), a large electrical resistance is exhibited due to the presence of the adhesive (3).

The corresponding conductive patterns (2) and (8) superimposed on each other in this way are electrically connected to each other by the fibrous conductor (4), and mechanically, the conductive patterns (2) and (8) are mainly connected to each other by the fibrous conductor (4). 8) are firmly connected by a sufficient amount of adhesive (3) filled in the parts other than the mutually overlapping parts.

Therefore, according to this example, there is an advantage that electrical connection and mechanical connection with other wiring boards are simple.

By the way, for example, the terminals (9a) of the IC (9) can be attached to a predetermined conductive pattern (2) provided on the flexible substrate (1) using an adhesive (with the above-mentioned fibrous conductor (4) uniformly dispersed and oriented). 3), as shown in Figure 3, it is mechanically attached only with the adhesive (3) between the fibrous conductors (4) and (4). Since the thickness of the adhesive (3) is only about 7 μm, for example, the diameter of the fibrous conductor (4), the adhesive force is weak and there are problems in terms of strength, reliability, etc. Also, when the electronic component such as IC (9) is relatively thick, the terminal of IC (9)
If the terminal (9a) of the IC (9), etc. is floating with respect to the IC chip body, it cannot be installed properly and the terminal (9a) of the IC (9) etc. is lifted up from the wiring board (1), which is the so-called springback. There was an inconvenience that this caused the electrical connection to become defective.

OBJECTS OF THE INVENTION In view of the above, an object of the present invention is to enable terminals of electronic components such as ICs to be properly attached to a wiring board with simple work.

SUMMARY OF THE INVENTION The present invention involves disposing terminals of electronic components on corresponding wiring patterns of a wiring board via an adhesive, placing a heat-shrinkable adhesive film over predetermined terminals of the electronic components, and The terminal portion of the electronic component is attached to the wiring board by heat-pressing the terminal portion of the component onto the heat-shrinkable adhesive film, and according to the present invention, the terminal of the electronic component such as an IC can be attached to the wiring board. can be easily attached to the wiring board with simple work.

EXAMPLE Hereinafter, an example of a method for attaching a terminal of an electronic component according to the present invention will be explained with reference to FIGS. 4 to 7. In FIGS. 4 to 7, parts corresponding to those in FIGS. 1 to 3 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In this example, a glass epoxy substrate with a thickness of 0.5 mm (
10) A predetermined conductive pattern (2
) flat package IC (9) on the wiring board (1)
This section explains how to install the .

In this example, first, as shown in FIG. 4, the terminals (
9a) is applied to the predetermined position where the fibrous conductor (4) is uniformly dispersed and oriented, for example, in the shape of an opening, so that the thickness after drying is 30 μm to form an adhesive layer. (5) is applied.

This adhesive layer (5) had the following composition.

Thereafter, as shown in FIG. 4, an adhesive layer (5) on the conductive pattern (2) (2) of this wiring board (1) is temporarily pressed for terminal attachment. The press pressure for this temporary crimping is 10KP.
/cm ~ 15KFI/crlL and the temperature of the press plate is 10
The temperature was 0°C to 120°C, and the pressing time was about 5 seconds.

Next, in this example, as shown in FIG. To attach the terminal, place the IC (
9) All the terminals (9a) (9a)... A heat-shrinkable adhesive film 0] cut out in the shape of a predetermined width, for example, is placed across the top.

As shown in Fig. 6, this heat-shrinkable adhesive film aυ is a biaxially stretched polyvarnish film (l) with a thickness of 50μ.
A heat-sensitive adhesive (for example, one mainly composed of Vylon 300 manufactured by Toyobo Co., Ltd.) was coated on one side of la) to cover an adhesive layer (llb) with a thickness of 50 μm.

After that, the terminals (9a) of the IC (9) are heat-pressed onto the heat-shrinkable adhesive film Ql), and the terminals (9a) (9a) of the IC (9) are attached to the wiring board (1). Installed. The conditions for heat-pressing at this time are that the press pressure is 50 Ky/c.
IIL ~ 100 to 2/crIL, the temperature of the press plate is 1
The temperature was 00°C to 150°C, and the pressing time was about 30 seconds to 60 seconds.

In this case, the terminal (9a) (9
When attaching a)... to the wiring board (1), as shown in Figure 7, the heat-shrinkable adhesive film aυ shrinks while the terminal (
9a) (9a)... is pressed against the wiring board (1).

Therefore, the adhesive strength of the terminals (9a) (9a)... of the IC (9) can be increased by this heat-shrinkable adhesive film (11), and this heat-shrinkable adhesive film (
11) contracts, this terminal (9a) (9
a) It is possible to prevent springback, etc., and improve the electrical connection. In addition, this heat-shrinkable adhesive film Ql
) covers the terminals (9a) (9a)... of the IC (9), so these terminals (9a) (9a)... can be insulated from others.

In the above embodiment, the fibrous conductor (4) is uniformly dispersed and oriented in the adhesive layer (5), but it is also possible to include low melting point metal particles instead. It is easy to understand that the same effects as those of the above-mentioned embodiments can be obtained even if the fibrous conductor (4) is not included. In addition, in the above-mentioned examples, 2 was used as the heat-shrinkable adhesive film Ql).
Although the adhesive layer (flb) was provided on one side of the axially stretched polyester film (lla), it is of course not necessary to provide the adhesive layer (llb) if the film (lla) itself has adhesive properties. Furthermore, although the above-mentioned embodiment describes an example in which IC terminals are attached, it is easy to obtain the same effects as described above even when the present invention is used when attaching terminals of other electronic components to the wiring board (1). I can understand it. Furthermore, it goes without saying that the present invention is not limited to the above-described embodiments, and can take various other configurations without departing from the gist of the present invention.

Effects of the Invention According to the present invention, there is an advantage that terminals of electronic components such as ICs can be properly attached to a wiring board with simple work.

[Brief explanation of the drawing]

Figures 1 and 2 are enlarged sectional views showing an example of how to attach a wiring board, Figure 3 is a partially enlarged sectional view showing an example of how to attach terminals of electronic components, and Figures 4 and 5 are FIG. 6 is a partially enlarged sectional view showing an example of a heat-shrinkable adhesive film, and FIG. FIG. 2 is a partially enlarged cross-sectional view for explanation. (1) is a wiring board, (2) is a conductive pattern, (3) is an adhesive, (5) is an adhesive layer, (9) is an IC, (9a) is an IC terminal, (11) is a heat shrinkable It is a adhesive film. Figure 1'fs2 diagram

Claims (1)

[Claims] Terminals of electronic components are arranged on the corresponding wiring patterns of the wiring board via adhesive, and a heat-shrinkable adhesive film is placed over the predetermined terminals of the electronic components, and the terminal portions of the electronic components are A method for attaching a terminal of an electronic component, characterized in that the terminal of the electronic component is attached to the wiring board by heat-pressing on the heat-shrinkable adhesive film.