JPH02220306A - Tape for tab and manufacture thereof and tape film for tab to be used therein - Google Patents

Abstract

PURPOSE:To prevent deformation or dislocation of an inner lead and to form a conductor pattern finely by providing a thin film of electronic insulating characteristic midway between a conductor layer and a base film. CONSTITUTION:A base film 14 is adhered to a junction body of a conductor part 10 and a thin film 12, for both of which the base film 14 is designed as a support body. On the base film, necessary holes such as a device hole 16, a sprocket hole 18, etc., are provided. After the base film 14, the conductor part 10, and the thin film 12 are connected with one another, a predetermined conductor pattern is formed on the conductor part 10. The thin film 12 is extended to one surface of the device hole 16, while an inner lead 10b is bonded with the film 12 and is supported.

Description

[Detailed description of the invention] (Industrial application field) The present invention f$ T A B (TapCΔuLomate
d Bonding) tape, its manufacturing method, and a TAB tape film used therefor.

(Prior Art) A TAB tape has a conductor pattern formed on a thin base film made of synthetic resin. This '1'
AB tape can form extremely high-density conductor patterns, making it suitable for increasing the number of pins.Also, when bonding to a semiconductor chip, the entire lead can be bonded at once without using wires, making it efficient. It has various advantages such as the ability to perform bonding.

TAB tapes vary depending on their structure: some consist of a single conductor layer, some consist of two layers: a conductor layer and a base film, and others consist of three layers: a conductor layer, a base film, and an adhesive layer that bonds them together. It is roughly divided into three types.

A two-layer TAB tape has a conductor layer and a base film bonded together without using an adhesive, and the manufacturing method is different from a three-layer TAB tape.6 Figure 5 shows a conventional example of a 3FIl TAB tape. shows.

In the figure, 1 is a base film, 2 is a conductor pattern, and 3 is an adhesive for bonding the base film 1 and the conductor pattern 2. The base film 1 is provided with necessary holes such as a device hole 4 and sprocket 1-holes 5. In this example, the inner lead portion extends inward from the periphery of the device hole 4, and the structure is such that the inner lead and the [C chip] can be directly bonded.

To make a 3-layer TAB tape with η construction 1. Normally, adhesive is applied to the base film, the required holes are punched through the base film, and copper foil is laminated as a conductor layer. Then, the copper foil is etched according to a predetermined conductor pattern to form a conductor pattern on the base film.

(Problem to be Solved by the Invention) As mentioned above, the "I" A B tape has conductor patterns such as inner leads formed at extremely high density.1 Usually, it is bonded directly to a semiconductor chip. Therefore, the inner leads are formed to extend inside the device hole.

In order to prevent the conductor pattern from deforming, the plating thickness of the conductor layer is set appropriately to maintain its strength, but the base film may deform during handling when transporting the product. This may cause deformation of the inner lead.

The conductor pattern formed on the TAB tape is much finer and denser than the conductor pattern formed on conventional lead frames T1, etc., so the inner lead may be deformed even slightly, or If it deviates from its position, a problem arises in that accurate bonding cannot be performed.

In addition, as another reference point, when bonding the tape for I'A[3 and the semiconductor chip, a bump for bonding is provided on either the semiconductor chip or the inner lead, and the bonding is performed via the bump. It is connected by thermocompression,
With conventional TAB tape, the base of the inner lead is simply glued to the base film, making the inner lead unstable.

There was a problem in that it was difficult to form bumps on the inner lead portion.

Therefore, the present invention has been made to solve the above-mentioned problems, and its purpose is to effectively prevent deformation and misalignment of the inner lead, and to form a fine conductor pattern. The present invention aims to provide a TAB tape that can easily form bumps on inner leads, a method for manufacturing the same, and a TAB tape film used for manufacturing the same.

(Summary of the Invention) In order to solve the above-mentioned problems, in the present invention, in contrast to the conventional three-layer TAB tape consisting of a base film, a conductor layer, and an adhesive layer, the present invention is made by combining a conductor layer and a base film. It is characterized by having an electrically insulating thin film interposed in the middle.

That is, in the TAB tape of the present invention, a thin film is stretched over a device hole formed in a base film, and inner leads are formed on this thin film.

In addition, a hole is etched in the thin film that supports the inner lead in the area corresponding to the tip of the inner lead.
Bumps can be formed in the hole portions by plating.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

[Example 1] FIGS. 1(a) to 1(c) are explanatory diagrams showing the 'r A B tape and the manufacturing method thereof according to the present invention.

FIG. 1(a) shows a sectional view of a joined body of a conductor part and a thin film, in which 10 is a conductor part and 12 is a thin film joined to the conductor part 10. As the book film 12, an electrically insulating film such as polyimide is used,
The joined body of the conductor part 10 and the thin film 12 is the conductor part 10
A method of laminating the copper foil and the thin film 12 using an adhesive, or a method of laminating the copper foil and the thin film 12 as
Conductor portion 1 is formed on top by sputtering, vapor deposition, plating, etc.
There is a way to form 0.

Next, as shown in FIG. 1(b), a base film 14 is attached to the joined body of the conductor portion 10 and the thin film 12. The base film 14 serves as a support for the conductor portion 10 and the thin film 12, and the base film 14 includes:
Device hole 16, sprocket hole 1 in advance
The necessary holes such as 8th grade are made transparent. These holes can be formed with high precision by normal punching. 20 is a thin film 12 and a base film 14
It is an adhesive that bonds the two. After the base film 14, conductor portion 10, and thin film 12 are bonded in this manner, a predetermined conductor pattern is formed on the conductor portion 10. The conventional method for forming a conductor pattern can be applied as is. For example, by providing a resist 1-pattern on the conductor portion 10 and removing unnecessary portions of the conductor portion, the conductor pattern can be formed as shown in FIG. 1(C). A TAB tape having a conductive pattern 10a as shown is obtained.

In the figure, reference numeral 10b indicates an inner lead of the conductor pattern. A thin film 12 is stretched over one side of the device hole 16 as shown in the figure, and the inner lead 10b is adhered to and supported by the thin film 12.

Figure 1<d) shows the above T A B tape IC chip 2.
2 is bonded and mounted on a substrate 24.

In this example, bumps 23 are formed on the IC chip 22 side, and the IC chip 22 is bonded to the inner lead 10b on the opposite side to the device hole 16. The outer peripheral portion of the base film 14 is cut off to form the support ring 1.
It remains as 4a.

Further, the external lead 10c of the conductive pattern 10a is connected to the substrate 2.
4 is connected to the conductor pattern 25 on the top.

In this TAB tape, since the inner leads 10b are adhered to and supported by the thin film 12, deformation of the inner leads 10b can be effectively prevented.

[Example 2] FIG. 2(a) is a sectional view of a TAB tape in which bonding bumps are formed on the inner leads 10b.

The manufacturing method is the same as that described in Example 1 above until the conductor part 10 is formed on the base film 14 via the thin film 12.Next, a resist pattern is formed on the conductor part in order to form a conductor pattern. The conductor pattern 10a is formed by removing unnecessary portions of the conductor portion using a method. At this time, a resist layer is formed on the thin film 12 corresponding to the portion where the bumps of the inner lead portion 10b are to be formed, and then holes are formed by dry etching. The bumps 26 are formed by opening and plating the conductor portions partially exposed.

Figures 2) and (C) show a method for forming bumps on the inner leads. In order to make the bumps protrude from the inner leads, the bumps are formed on the thin film 12 before etching the holes. Figure 2(b) shows that the bumps 26 can be made to protrude from the thin film 12 by removing the resist 1-28 after plating.

The reason why bumps can be formed corresponding to the positions of the inner leads 10b in this way is that the conductor patterns 10a are reliably supported by the thin film 12 and are reliably positioned. Even after the bumps 26 are formed, the inner leads 10b are supported on the t-refilm 12, and the effect of preventing deformation of the inner leads 10b is the same as in the first embodiment.

FIG. 2(d) shows T A B provided with the bump 26.
Bond the IC chip to the Jl+ tape and attach the board 24.
An example of implementation is shown below. TAB with bumps of this example
In this tape carrier, the IC chip 22 is bonded to the device hole 16 side of the base film 14.

[Embodiment 3] The embodiment shown in FIG. 3 is an example in which the conductor pattern loa formed on the thin film 12 is coated and further provided with bumps. The steps up to forming the conductor pattern 10a on the base film 14 are the same as in each of the above embodiments.

In FIG. 3(a), 30 is a coating that covers the conductor pattern 10a. This coating can be applied by printing or the like.

FIG. 3(b) shows a state in which bumps 32 for bonding are provided on the coating surface side of the inner lead 10b. When providing the bumps 32, a resist layer is further formed on the coating 30 to make a two-layer resist layer, and resists 1 to 30 at positions corresponding to the inner leads 10b are etched to make holes.
The surface is exposed and plated. Then, the bumps 32 can be formed by removing only the upper resist layers 1 to 1.

FIG. 3(c) shows coating 3 for bonding the TAB tape to the IC chip and mounting it on the board.
This figure shows a state in which a portion 36 corresponding to the external lead portion of the conductor pattern 10a of No. 0 has been etched and removed.

FIG. 3(d) shows a state in which an IC chip is bonded to the TAB tape and then mounted on a board.

The IC chip 22 is connected to the inner lead 1 via the bump 32.
0b, and the external lead 10 of the conductor pattern 10a
c is connected to the circuit pattern 25 on the substrate 24. In this third embodiment, the coating 30 of the conductor pattern 10a
The bumps 32 were formed on the side where the conductive pattern 10a was formed, but in this case as well, the thin film 1 of the conductive pattern 10a
Of course, it is also possible to form bumps on the second side. That is, by employing a method of coating the conductor pattern 10a, the IC chip can be formed in either a face-up or face-down configuration.

As in Example 3, when the conductor pattern 10a is covered with the coating 30, the inner lead 10b is further supported by the coating 30 than when only the film 12 is used, and the deformation of the inner lead 10b is prevented. The prevention effect is further improved. Another effect of the coating is that migration of copper in the loa portion of the conductor pattern can be prevented.

In each of the embodiments described above, an example was given in which the tip of the inner lead was arranged at the periphery of the device hole.
In the TAB tape described above, since the conductor pattern is supported by the thin film 12, it is possible to extend the inner lead long to the center inside the device hole. In this way, the inner lead can be pulled out to the center inside the device hole, which expands the placement range of the inner lead, and allows for a wide variety of inner lead patterns to be selected. This has the great effect of eliminating deformation. Furthermore, by doing so, it becomes possible to widely use not only the periphery of the IC chip but also the entire surface of the IC chip for connection.

In addition, as shown in each of the above embodiments, since the conductor pattern is always bonded to the thin film 12, the conductor pattern can be reinforced by the strength of the thin film 12, and the conductor portion of the copper foil tube when forming the conductor pattern can be reinforced. Extremely F, thick,
This has the advantage that fine etching becomes easy and ultra-fine patterns can be easily formed. When a fine pattern is formed, by applying a coating as shown in Example 3, it is possible to reliably protect the conductor pattern. Further, an extremely thin conductor portion can also be used as it is as a conductor pattern.

In addition, as shown in Figure 4, there is a known TAB tape that allows the inner lead to be freely pulled out to the center of the device hole as described above and eliminates the risk of deformation of the inner lead. TAB tape is
Through hole 33 filled with conductor in base film 14
It is extremely difficult to form a fine conductor pattern, and after connection with an IC chip, the connected portion is likely to peel off due to warping of the thick base film 14.

Although the present invention has been variously explained above using preferred embodiments, the present invention is not limited to these embodiments.
Of course, many modifications can be made within the scope of the invention.

(Effects of the Invention) According to the present invention (7pTAB tape), as described above, the conductor pattern provided on the base film is bonded to the pace filter t1 via the thin film, so the conductor pattern is always attached to the thin film. The conductor pattern can be supported and positioned reliably, and the inner leads can be prevented from being deformed or misaligned.This makes it easier to transport, carry, and handle the TAB film.

Further, since deformation of the inner lead can be prevented, accurate bonding is possible, and the positioning of the inner lead can be ensured, and the conductor pattern can be easily formed into a finer structure.

Furthermore, since the conductor pattern is supported by the thin film, it becomes easy to form bumps for bonding on the inner lead portion.

[Brief explanation of the drawing]

FIGS. 1(a) to (d) are explanatory diagrams showing the first embodiment of the TAIl tape according to the present invention and its mounting state, and FIGS. 2(a) to (d) are the second embodiment and its mounting state. Explanatory diagram 1 showing the state. 3(a) to 3(d) are explanatory diagrams showing the third embodiment and its mounting state; FIG. 4 is an explanatory diagram showing an example of the arrangement of the inner leads drawn out into the device hole;
The figure is an explanatory diagram showing a conventional TAB tape. 10... Conductor part, 10a... Conductor pattern,
10b...inner lead, 10c/0. External lead, 12... Thin film, 14... Suhole, 22... 26... 30... Base film, 16... Debye 18... Sprocket hole. IC chip, 24...Substrate, bump, 28...Resist, coating, 32...Bump. (& la (b) Fig.

Claims (1)

[Claims] 1. A conductive part such as copper foil for forming a conductive pattern is bonded to a base film in which required holes such as device holes and sprocket holes are formed through a thin film having electrical insulation properties. Tape film for TAB. 2. A TA in which a conductive pattern is bonded to a base film in which required holes such as device holes and sprocket holes are formed, via a thin film having electrical insulation properties.
B tape. 3. The TA according to claim 2, wherein a bonding bump that is electrically connected to the inner lead is formed in the hole provided in the thin film to which the inner lead is bonded.
B tape. 4. The TAB tape according to claim 2 or 3, wherein the conductor pattern on the side not bonded to the thin film is covered with a protective coating. 5. A bonded body of an electrically insulating thin film and a conductor such as copper foil is attached to a base film in which required holes such as device holes and sprocket holes have been formed in advance, and a resist pattern is applied to the conductor. A method for producing a TAB tape, which comprises forming a predetermined conductive pattern on a thin film by forming and etching it.