JP2000308997A - Die for application of semiconductor-chip-mounting adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a die for application of semiconductor-chip-mounting adhesive tapes that can apply a uniform load to different adhesive sheets and thus suppress dispersion in quality even if the adhesive sheets differ in thickness or the pressure-application stage has an inclination. SOLUTION: The die has two or more punches 5a to 5c for punching a semiconductor-chip-mounting adhesive tape 9 and apply these punched sections under pressure to prescribed places of a TAB tape 20 or a lead frame. The region in which a backing plate 10 and a punch holder 4 face each other includes one space 3 accommodating the back ends of the punches 5a to 5c. The space 3 is hermetically filled with liquid as a punch pressuring medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for punching out an adhesive tape portion (adhesive sheet) having a predetermined shape from an adhesive tape, and
A die for attaching an adhesive tape for mounting a semiconductor chip to be attached to an AB tape or a lead frame, particularly 2
The present invention relates to a mold for attaching an adhesive tape to more than one location.

[0002]

2. Description of the Related Art At present, with the miniaturization of semiconductor packages, various types of packages having a size substantially equal to the chip size have been developed. Among them, US Tessera (T
In recent years, a micro ball grid array (μBGA) package devised by ESSERA) has attracted attention as a highly reliable package.

The μBGA package is a CSP of a tape BGA type, and has a structure in which an elastomer (low elastic resin) is interposed between a chip and a TAB tape, and further, the chip and the TAB tape are connected by S-shaped leads. .
In the μBGA technology, since an elastomer is interposed between the chip and the TAB tape, thermal stress generated between the package and the printed board can be reduced, and the life of the solder ball joint can be improved.

On the other hand, in the method of forming the above-mentioned elastomer in the μBGA package structure, conventionally, a silicone-based elastomer is printed on a TAB tape and an adhesive is applied thereon. Therefore, workability was poor and the process was complicated. That is, the liquid silicone resin is printed (coated, cured) on the tape carrier to form an elastomer,
Due to the thick film printing, it is difficult to obtain flatness, and there is a problem that adhesive printing must be performed again at the time of chip mounting.

In order to solve this problem, a double-sided film elastomer (film-like elastomer) also serving as a chip adhesive is punched out by a press, and a TA is used.
We are developing a method to attach to B tape.

[0006] FIG. 4 shows a μBG using the above TAB tape.
1 shows an assembly process for manufacturing a semiconductor device having an A structure.

A TAB tape 20 having a wiring pattern 22 including lands 23 and wiring leads 24 provided on one side of a tape base 21 made of an insulating film is formed by pressing an elastomer sheet 31 from a continuous tape-shaped elastomer tape into a sheet. Is attached and T with elastomer for BGA
An AB tape 40 is formed (FIG. 4A).

This TAB tape with elastomer for BGA 4
0, the semiconductor chip 50 is mounted (FIG. 4).
(B)). The semiconductor chip 50 is adhered to the TAB tape 20 via an elastomer sheet 31 which is a double-sided adhesive film.

Next, the inner lead 24a of the TAB tape 40 with elastomer for BGA is formed in an S-shape by a bonding tool and connected to the electrode pad 51 as a terminal electrode of the semiconductor chip 50 (FIG. 4C). Next, the electrode pad 51 and the lead 2 of the joined semiconductor chip 50
4a is sealed with a sealing resin 60 (FIG. 4D). Then, the solder ball 70 is mounted on the land 23 of the TAB tape 20 (FIG. 4E), and laser marking or printing is performed on the chip surface (FIG. 4F). Finally, it is cut into individual pieces by punching out a TAB tape 40 with an elastomer for BGA to obtain a μBGA package.

As described above, in the production of the μBGA package, the double-sided adhesive elastomer sheet 31 is first attached to the surface of the tape base 21 on the side where the wiring pattern 22 exists.

The attachment of the elastomer sheet 31 is as follows.
As shown in FIG. 5, using a die for attaching an adhesive tape for mounting a semiconductor chip including a punch 5, a die plate 8, a stripper 6, and a pressure bonding stage 7, for example, a continuous tape shape in which an adhesive is formed on both surfaces of a porous core Is pressed into a sheet-like elastomer sheet 31 by a press, and is bonded to the TAB tape 20 by pressure bonding on the pressure bonding stage 7 composed of a heat block.

[0012]

The die for punching and bonding an adhesive tape to a TAB tape or the die for punching and bonding an adhesive tape to a lead frame as described above usually uses a plurality of punches having the same shape.

That is, a film-shaped adhesive tape such as an elastomer tape set on a die is punched into a predetermined shape by a plurality of punches having the same shape. Press down the punch as it is, and TAB that has been positioned and heated in advance on the pressure bonding stage 7 located at the die opening
Carry until the punched adhesive sheet comes into contact with the tape or the lead frame. Thereafter, the backing plate (rigid body) on the back of the punch is pressed by a press or the like. This pressure is transmitted to the adhesive sheet through the punch, and the adhesive sheet is pressed against the lead frame or TAB.

However, there is a variation in the thickness between the adhesive sheets punched at the same time, so that even if the surface positions of the punches are aligned, uniform pressing cannot be performed. Further, the length between the punches varies, and even if the punched adhesive tape has the same thickness, uniform pressing cannot be performed. For this reason, the pressure-bonding load differs for each adhesive tape, and the quality such as the adhesive strength varies.

Further, when the parallelism between the pressure-bonding stage and the tip of the punch is poor, the pressure-bonding load changes continuously between adjacent adhesive sheets. In the case of a low load, there is a problem of non-adhesion, and in the case of a high load, there is a problem of sticking out of the adhesive. Further, there is a problem that the thickness of the adhesive sheet after pressure bonding varies. For this reason, since it is necessary to provide parallelism with high precision, efficiency is poor and uneconomical.

Therefore, an object of the present invention is to solve the above-mentioned problems, and to apply a load evenly to a plurality of adhesive sheets even if there is a variation in the thickness of the adhesive sheets or the inclination of the pressure bonding stage. An object of the present invention is to provide a die for attaching an adhesive tape for mounting a semiconductor chip, which can suppress variations in quality.

[0017]

In order to achieve the above object, a die for attaching an adhesive tape for mounting a semiconductor chip according to the present invention is formed by punching out an adhesive tape for mounting a semiconductor chip.
In a mold having two or more punches to be pressure-bonded to a predetermined position of a TAB tape or a lead frame, a continuous space in which a back surface of each punch is located is provided in a region where a backing plate and a punch holder are in contact with each other. And a liquid as a punch pressurizing medium.

The gist of the present invention resides in that a continuous space is provided in a region surrounded by a plurality of punch back surfaces, a punch holder and a backing plate, and a liquid is sealed in the space. Thus, by transmitting the pressure of one lump of liquid to each adhesive tape via a plurality of punches, it becomes possible to perform pressure bonding while applying a uniform load to all the adhesive tapes that are pressed at once.

The space may be formed by providing a concave portion on either side or both of the backing plate and the punch holder. Preferably, a concave portion is provided on the surface of the backing plate that is in contact with the punch holder, and the concave portion and the punch holder that covers the concave portion are formed. This is because the thickness of the punch holder can be sufficiently secured as compared with the form in which the concave portion is provided on the punch holder side, and the manufacturing becomes easier as compared with the form in which the concave portion is provided on both the backing plate and the punch holder side.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

FIG. 1 shows a cross section of a mold for explaining an embodiment of the present invention.

The die for attaching an adhesive tape for mounting a semiconductor chip is configured to have a pressure bonding stage 7 in addition to an upper die and a lower die.

As an upper mold, a shank (holding body) 2 is attached to a press platen (not shown), and a backing plate (rigid body) 10 is connected to the shank 2 via a hanger 13. This backing plate 1
Numeral 0 is vertically movably inserted into guide posts 12 erected at four locations around the die holder 14.

A punch holder 4 is fixed to the lower surface of the backing plate 10 by bolts or the like. The punch holder 4 has a plurality of punches, here three punches 5.
a, 5b and 5c are attached.

In the area where the backing plate 10 and the punch holder 4 are in contact with each other, the punches 5a, 5b, 5
A continuous space 3 in which the rear surface of c is located is formed, and a liquid is sealed in the space 3 as a punch pressurizing medium. Here, the liquid enclosing space 3 is formed by a concave portion provided on the surface of the backing plate 10 which is in contact with the punch holder 4, and a punch holder covering the concave portion, and grease is enclosed as a liquid.

The rear ends of the three punches 5a, 5b, 5c penetrate the punch holder 4 in the vertical direction, and are held so as to be independently displaceable vertically. The rear surfaces of the punches 5a, 5b, 5c are located in the liquid filling space 3. Therefore, for example, when one of the punches 5a, 5b, 5c is displaced in the upward direction and the position on the back surface of the punch 5a, 5b, 5c is raised, the pressure acting on the back surface of the other punches 5a, 5b, 5c is increased by the action of the enclosed mass of liquid. The punch 5a, 5b, and 5c are configured to be pushed downward by a corresponding displacement amount.

On the other hand, as a lower die, a die holder 14 is set on a block 15 fixed on a mount 16 such as a surface plate, and the punch 5 is placed at the center of the die holder 14.
a, 5b, 5c, three die openings 8a, 8b,
The die 8 provided with 8c is fixed.

The pressure bonding stage 7 is composed of a heat block heated to a predetermined temperature, and is fixed on a mount 16 such as a surface plate. The upper surface of the heat block is located immediately below the die 8 at a predetermined distance from the die 8.

Next, the operation will be described.

An adhesive tape 9 made of an elastomer tape 30 is placed on the die 8, and a TAB tape 20 (or a lead frame) is placed on the pressure bonding stage 7.

The punch holder 4 moves up and down along the guide post 12 integrally with the backing plate 10 located above the punch holder 4. The required force is an external force acting on the shank 2 from a press machine (not shown) when descending, and an extension force of a contracted spring (not shown) when ascending.

When the upper die is pressed in a die pressing direction indicated by an arrow 1 by a press (not shown), the punches 5a, 5a
b and 5c fall.

The punches 5a, 5b, 5c can move up and down in a not-shown hole of a stripper, and the tips thereof cooperate with die openings 8a, 8b, 8c arranged opposite thereto. Then, the adhesive tape 9 placed on the die 8 is punched into a predetermined shape. The punches 5a, 5b and 5c are provided with an adhesive sheet 11 made of a punched elastomer sheet 31 (FIG. 2).
Is transferred to the pressure bonding stage 7 as it is, and is attached to the TAB tape 20 located on the pressure bonding stage 7. That is, the adhesive sheet 11, which is an adhesive tape portion punched out of the adhesive tape 9, descends together with the punches 5a, 5b, and 5c and is pressed against the TAB tape 20, and both are heated by a heat block, so that the TAB tape 2 is heated.
0.

In the above operation, the punches 5a, 5b, 5
The rear end of the punch 5a, 5b, 5c is sealed in the liquid sealing space 3 because the rear end of the punch c is located in the liquid sealing space 3 of the backing plate 10 after penetrating the punch holder 4. Restrained by grease. This is because the volume of grease sealed in the liquid sealing space 3 is constant. However, even under the condition that the volume of grease is constant, if the punches 5a, 5b, and 5c have the same amount of penetration into the liquid sealing space 3, the punches 5a, 5b
The heights of b and 5c are displaceable between the punches 5a, 5b and 5c.

FIG. 2 shows an adhesive tape 9 having different thicknesses.
This is an operation in a case where various types of adhesive tapes 9a and 9b are pressure-bonded. Here, a 100 μm adhesive tape 9a
And an adhesive tape 9b of 200 μm is prepared.
Is set on the die openings 8a and 8c on both sides, and the 200 μm adhesive tape 9b is set on the center die opening 8a.
b.

As shown in FIG. 2, an adhesive tape 9a of 100 μm and an adhesive tape 9b of 200 μm were simultaneously punched out and pressed on a TAB tape 20. At the time of this pressure bonding, the central punch 5b pushed the grease in accordance with the thickness of the adhesive tape 9b, and entered the grease in the liquid sealing space 3 relatively deeply. This also allows the left and right punches 5a,
5c was pushed out of its original position by the pressure of grease. The adhesive sheets 11a, 11b, 11a punched from the adhesive tapes 9a, 9b, 9a have punches 5a, 5b,
Grease pressure is applied via 5c. The adhesive sheets 11a and 11b having different thicknesses could be adhered to the TAB tape 20 without any unadhered portions and no protruding adhesive.

FIG. 3 shows that the crimping stage 7 is intentionally tilted,
This shows an operation when the adhesive sheet 11 is attached to the TAB tape 20 placed thereon. Here, the upper surface of the pressure-bonding stage 7 having a width of 50 mm
The punches 5a, 5b, and 5c were inclined by 0 μm in the arrangement direction. The punch 5a on the left side according to the inclination of the pressure bonding stage 7.
Pushed the grease, and the right punch 5c was pushed out by the grease. Each of the three adhesive sheets 11 affixed by the punches 5a, 5b, and 5c was adhered to the TAB tape 20 without any unadhered portions and no protrusion of the adhesive.

In the above embodiment, the case where the adhesive sheet is attached to the TAB tape has been described as an example. However, the present invention can be applied to the case where the adhesive sheet is attached to the lead frame.

[0039]

As described above, the present invention relates to a die having two or more punches for punching a TAB tape or a lead frame at a predetermined position by punching out an adhesive tape for mounting a semiconductor chip. A continuous space in which the back surface of each punch is located is provided in the area where the punch holder contacts, and the space is filled with a liquid as a punch pressurizing medium. By transmitting the adhesive tape to each of the adhesive tapes through the intermediary, it is possible to perform the pressure bonding while applying an equal load to all the adhesive tapes that are pressed at once.

Therefore, it is possible to eliminate the load variation at the time of sticking, which has been a problem in the prior art, and to maintain uniform adhesive characteristics with a plurality of adhesive tapes.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a die for attaching an adhesive tape for mounting a semiconductor chip according to the present invention.

FIG. 2 is a diagram illustrating an operation example of a die for attaching an adhesive tape for mounting a semiconductor chip according to the present invention.

FIG. 3 is a view showing another operation example of the die for attaching an adhesive tape for mounting a semiconductor chip according to the present invention.

FIG. 4 shows μ using a TAB tape with an elastomer for BGA.
FIG. 3 is a diagram showing a manufacturing process of the BGA semiconductor device.

FIG. 5 is a diagram schematically showing a die for attaching an adhesive tape for mounting a semiconductor chip, which punches out an elastomer tape and attaches it to a TAB tape.

[Explanation of symbols]

3 Liquid Enclosure Space 4 Punch Holder 5, 5a, 5b, 5c Punch 7 Crimping Stage 8 Die 8a, 8b, 8c Die Opening 9, 9a, 9b Adhesive Tape 10 Backing Plate 11, 11a, 11b Adhesive Sheet (Punched Adhesive Tape Part) 14 Die holder 20 TAB tape 30 Elastomer tape 31 Elastomer sheet 40 TAB tape with elastomer for BGA

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3C060 AA20 BA01 BC01 BE09 BF02 4J040 JA09 MA02 NA20 PB17 5F047 AA11 AA17 BA40 BB03 BB16 FA23 5F067 CC10

Claims (2)

[Claims] In a mold having two or more punches for punching an adhesive tape for mounting a semiconductor chip and pressing it at a predetermined position on a TAB tape or a lead frame, an area where a backing plate and a punch holder are in contact with each other is provided. A die for attaching an adhesive tape for mounting a semiconductor chip, wherein a continuous space in which the back surface of each punch is located is provided, and a liquid is sealed in the space as a punch pressurizing medium. 2. The semiconductor chip mounting according to claim 1, wherein said space is formed by a concave portion provided on a surface of said backing plate which is in contact with said punch holder, and a punch holder covering said concave portion. Adhesive tape pasting mold.