JP2000077462A - TAB tape sticking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deformation of a flexible film and stabilize simultaneous bonding of a heat transfer agent when attaching a flexible film on which an integrated circuit chip is mounted to a support ring in manufacturing an integrated circuit package. The purpose is to let them. An attaching device (20) including a mounting table (22) for mounting a support ring (4) and a crimping punch (36) covered with an elastic material (44) includes an elastic material (20). 44) and a low friction sheet (4) made of polytetrafluoroethylene between the flexible film (2)
6) is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sticking apparatus for sticking a flexible film on which an integrated circuit chip is mounted to a support ring in manufacturing an integrated circuit package.

[0002]

2. Description of the Related Art A ball grid array type integrated circuit package manufactured using a TAB (Tape Automated Bonding) tape is known. As shown in FIG. 1A, this type of integrated circuit package includes an integrated circuit chip 1,
Flexible film 2 formed from TAB tape,
Potting resin 3 for protecting the integrated circuit chip and its inner leads, support ring 4 for supporting the flexible film, heat spreader 5 for diffusing the heat generated by the integrated circuit chip, and transferring the heat of the integrated circuit chip to the heat spreader A heat transfer agent layer 6 such as a silver paste, a solder ball 7 called a bump connected to an external lead of the flexible film, and the like. This integrated circuit package is mounted on the substrate 8 by thermocompression bonding the solder bumps 7 to the substrate 8.

[0003] This type of integrated circuit package is manufactured using TAB tape. That is, in the manufacturing line, the electrode pads of the integrated circuit chip 1 are connected to the external leads formed on the TAB tape by thermocompression bonding or the like, and the individual integrated circuit chips are sealed with the potting resin 3, so that a series of A long TAB tape on which the integrated circuit chip is mounted is manufactured. Next, this TAB tape is cut into each integrated circuit chip unit, and the assembly of the flexible film 2 and the integrated circuit chip 1 cut in this manner is attached by an attaching device as shown in FIG. Affixed to support ring 4. For this purpose, the support ring 4 whose surface is coated with an adhesive in advance and the heat spreader 5 are joined, and this support ring / heat spreader assembly is mounted on the mounting table 9 of the attaching device, and the pressure punch 10
By pressing the flexible film 2 against the support ring 4, the flexible film 2 and the support ring 4 are attached.

[0004] In this attaching step, air bubbles 1 are interposed between the flexible film 2 and the interface of the adhesive of the support ring 4.
When the package 1 is taken in, when the package is heated for thermocompression bonding of solder bumps in a post-process of mounting the integrated circuit package on the substrate, the flexible film 2 swells and deforms as shown in FIG. In some cases, adjacent solder bumps may unintentionally come into contact with each other. Similarly, if there is unevenness in the pressure of the pressure bonding punch 10 in the attaching step, peeling 12 of the flexible film 2 occurs at the time of heating for mounting the substrate, as shown in FIG. May come in contact. In order to prevent such a problem, in the related art, as shown in FIG.
The pressure bonding punch 10 of the attaching device is covered with an elastic material 13 such as rubber so that the pressure of the pressure bonding punch 10 is uniformly applied to the flexible film and the support ring.

[0005]

The problem of the conventional sticking device relates to the heat transfer agent layer 6 for transferring the heat of the integrated circuit chip to the heat spreader. That is, as described above with reference to FIG. 1A, in this integrated circuit package, the heat of the integrated circuit chip is transmitted to the heat spreader, so that the integrated circuit chip 1 and the heat spreader 5 are connected by heat transfer such as silver paste. They are connected by an agent layer 6. As shown in FIG. 2 (A), the heat transfer agent layer 6
4 is applied, the flexible film and the support ring are attached by an attaching device, and then the silver paste 14 is heated and cured at, for example, 150 ° C. for about 15 to 30 minutes. The cured heat transfer agent layer 6 adheres to the heat spreader 5.

However, in the conventional sticking apparatus, the press-fitting punch 10 is covered with the elastic material 13 for the above-described reason. Therefore, when the press-fitting punch 10 is pressurized, the elastic material 13 is covered with the elastic material 13 shown in FIGS. As shown by an arrow in FIG. As a result of such elastic deformation of the elastic member 13, the flexible film 2 is applied to the flexible film 2 in a direction perpendicular to the pressure applied by the pressure bonding punch 10 (see FIGS.
(In the direction indicated by the arrow in FIG. 3), the flexible film 2 is deformed. Further, since the elastic material 13 is crushed by pressing, the elastic material 13 protrudes inward by a distance L from the inner contour of the support ring 4 as shown in FIG.
At the time of pressurization, the flexible film 2 is deformed downward,
When unloading, the flexible film tends to return to its original state due to its elastic force.

Due to these deformations of the flexible film, the relative positions of the integrated circuit chip 1 and the heat spreader 5 change in the vertical direction as shown by arrows in FIG. As a result, the wetting of the heat transfer agent layer 6 to the heat spreader 5 deteriorates, and FIG.
As shown in (B), “shrinkage” 15 occurs in the heat transfer agent layer 6. The shrinkage especially originates from the corners. Since the heat transfer performance of the heat transfer agent layer 6 is determined by the connection area, the occurrence of the shrinkage 15 is smaller than that in the normal state of the heat transfer agent layer 6 shown in FIG. The heat transfer performance of the agent layer 6 will be significantly reduced.

An object of the present invention is to provide a flexible film on which an integrated circuit chip is mounted on a support ring so that deformation of the flexible film can be suppressed, and therefore, the adhesion of the heat transfer agent can be stabilized. An object of the present invention is to provide a sticking device.

[0009]

SUMMARY OF THE INVENTION The present invention comprises a mounting table for mounting a support ring, a crimping punch covered with an elastic material, and a flexible board on which an integrated circuit chip is mounted in manufacturing an integrated circuit package. In a sticking device for sticking a film to a support ring, a low friction sheet made of fluororesin or the like is arranged between the elastic material and the flexible film.

As described above, since the low friction sheet is interposed between the elastic material of the pressure bonding punch and the flexible film,
The elastic material can easily slide on the low friction sheet. Therefore, even when the elastic material is elastically deformed in a direction perpendicular to the pressing force of the press-fitting punch when the press-fitting punch is operated, slippage occurs between the elastic material and the low-friction sheet,
The elastic deformation of the elastic material in the direction perpendicular to the pressing force is not transmitted to the flexible film. Therefore, a force is applied to the flexible film only in the pressing direction of the pressure bonding punch.

In a preferred embodiment, the resilient material has an inner profile that is recessed outside the inner profile of the support ring. With this configuration, even if the elastic material is crushed, the elastic material does not protrude from the support ring to the inside, so that the deformation of the flexible film can be further suppressed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring mainly to FIG. 6, an apparatus 20 of the present invention for attaching a flexible film on which an integrated circuit chip is mounted to a support ring includes a mounting table or a mounting table 22 and a mounting table 22. Post 2 fixed to
4 and a top plate 26 supported by the columns 24. The mounting table 22 is formed with a recess 28 corresponding to the support ring 4 so as to position the pre-assembled assembly of the support ring 4 and the heat spreader 5. Further, at least two positioning pins 30 are provided on the mounting table 22, and the perforations 32 (FIG. 7) of the flexible film 2 formed of TAB tape are provided.
By engaging these positioning pins 30 with
The flexible film 2 on which the integrated circuit chip 1 is mounted is positioned with respect to the mounting table 22. Although not shown in the drawing, the mounting table 22 has a built-in heater to heat the silver paste 14 applied to the surface of the integrated circuit chip 1 or the thermoplastic adhesive applied to the support ring 4 in advance. It has become.

A slider 34 is mounted on the column 24 so as to be slidable in the vertical direction, and a movable member 38 on which a crimping punch 36 is mounted is mounted on the slider 34. A pressurizing device 40 such as an air cylinder for lowering the pressing punch 36 and applying pressure is mounted on the top plate 26, and an output shaft 42 of the pressurizing device 40 is connected to the movable member 38.

As in the conventional sticking device shown in FIG. 2, a rectangular annular elastic member 44 made of neoprene rubber or the like is attached to the press-fitting punch 36. As can be clearly seen from FIG. 6, in accordance with one aspect of the present invention, the inner profile 44A of the resilient material 44 is recessed more outward than the inner profile 4A of the support ring 4.

Immediately below the elastic member 44 attached to the press-fitting punch 36, a low friction sheet 46 made of a fluororesin such as polytetrafluoroethylene and having a small friction coefficient and flexibility is provided by a movable holder 48. Positioned. Referring to FIG. 6 and FIG.
Consists of a pair of vertical rods 50 slidably inserted into the movable member 38 in the vertical direction, stoppers 52 provided at the heads of these rods 50, and a rectangular frame 54 attached to the lower ends of the rods 50. The low friction sheet 46 is attached to the lower surface of the frame 54 by bonding or the like. This holder 48
Slides vertically with respect to the movable member 38, so that the low-friction sheet 46 approaches or separates from the flexible film 2 in accordance with the vertical movement of the pressing punch 36.
The low friction sheet 46 has a square shape, and a square opening 56 (FIG. 8) is formed in the center.

Next, the operation and use of the device 20 will be described. When attaching a flexible film on which an integrated circuit chip is mounted to a support ring, the assembly of the support ring 4 and the heat spreader 5 is attached to the mounting table 2.
The assembly is positioned on the mounting table 22 by fitting into the second recess 28. An adhesive is applied to the upper surface of the support ring 4 in advance. Next, an assembly of the integrated circuit chip 1, the flexible film 2, and the potting resin 3 coated with a silver paste 14 for forming the heat transfer agent layer 6 is applied to the perforation 3 of the flexible film 2.
By engaging the pin 30 with the pin 2, positioning is performed on the mounting table 22.

After positioning the flexible film assembly and the support ring assembly in this manner, the pressing device 40
Is operated, the holding tool 48 moves down together with the press-fitting punch 36 mounted on the movable member 38, and first, the low friction sheet 46
Abuts on the flexible film 2 and then the elastic material 44
Comes into contact with the low friction sheet 46. Crimp punch 36
Is further lowered, the flexible film 2 comes into close contact with the support ring 4, and both are adhered by the adhesive applied to the surface of the support ring 4. At the same time, the silver paste 14 applied to the surface of the integrated circuit chip 1 adheres to the heat spreader 5 and is cured by heating to form the heat transfer agent layer 6.

In these steps, since the low friction sheet 46 is interposed between the elastic member 44 and the flexible film 2, as the elastic member 44 is compressed by the pressing punch 36, the pressing force of the pressing punch 36 is reduced. When the elastic member 44 is elastically deformed in a direction perpendicular to the direction, the elastic member 44
A slip occurs between the low friction sheet 46 and the low friction sheet 46 along the contact surface between them. Therefore, a force in a direction perpendicular to the pressing force of the pressure bonding punch 36 is not transmitted to the flexible film 2, and a force is applied to the flexible film 2 only in the pressing direction of the pressure bonding punch. Also, as shown in FIG. 6, the inner contour 44A of the elastic member 44 is
Since the elastic member 44 is retracted outside the inner contour 4A of the support ring 4, the elastic member 44 does not protrude inward from the inner contour 4A of the support ring 4 even if the elastic member 44 is crushed. Can be suppressed. Therefore, the “shrinkage” described above with reference to FIG. 5B does not occur in the heat transfer agent layer 6.

When the attachment of the flexible film 2 and the support ring 4 and the adhesion and curing of the heat transfer agent layer 6 are completed,
When the pressing punch 36 is retracted, the low friction sheet 46 made of polytetrafluoroethylene is easily separated from the flexible film 2. The intermediate product of the integrated circuit package thus obtained is cut along a cutting line indicated by a broken line 58 in FIG. 7 to cut off an edge of the perforation 32, and then subjected to a solder bump welding step or the like. Sent.

Although a specific embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications and changes can be made. For example, low friction sheet 4
6 may be adhered to the elastic member 44 instead of being attached to the holder 48. However, in this case, there is a problem that the adhesive portion is peeled off due to expansion and contraction of the elastic material 44.

[0021]

As described above, the "shrinkage" of the heat transfer agent layer can be achieved by interposing a low friction sheet between the elastic material of the pressure bonding punch and the flexible film according to the present invention.
Therefore, an integrated circuit package having excellent heat transfer performance can be obtained. Another advantage of the low friction sheet is that the elastic material 44 of the crimping punch does not stick to the workpiece (flexible film) and is easily peeled off. Accordingly, work productivity is improved. According to a preferred embodiment, when the inner contour of the elastic material is retracted outside the inner contour of the support ring, the deformation of the flexible film can be further suppressed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a conventional ball grid array type integrated circuit package using a TAB tape mounted on a substrate.

FIG. 2 is a cross-sectional view of a conventional attaching device.

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is an enlarged sectional view of a portion inside a circle IV in FIG. 2 (B).

FIGS. 5A and 5B are cross-sectional views of the integrated circuit package, wherein FIG. 5A shows a normal wetting state of the heat transfer agent layer, and FIG.

FIG. 6 is a cross-sectional view of the attaching device of the present invention.

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;

FIG. 8 is a sectional view taken along line VIII-VIII in FIG.

[Explanation of symbols]

 1: integrated circuit chip of integrated circuit package 2: flexible film of integrated circuit package 4: support ring of integrated circuit package 20: sticking device 22: mounting table 36: crimping punch 44: elastic material 46: low friction sheet 48: low friction Sheet holder

Claims (4)

[Claims] 1. A mounting board for mounting a support ring, and a crimping punch covered with an elastic material, for attaching a flexible film on which an integrated circuit chip is mounted to the support ring when manufacturing an integrated circuit package. The bonding device according to claim 1, wherein a low friction sheet is disposed between the elastic material and the flexible film. 2. The application device according to claim 1, wherein the elastic member has an inner contour that is recessed outside an inner contour of the support ring. 3. The sticking device according to claim 1, wherein the low friction sheet is made of a fluororesin. 4. The sticking device according to claim 1, wherein the low friction sheet is mounted on a holder so as to be able to approach and separate from the flexible film.