JP2001127117A - Method for manufacturing tab tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a tab tape which can enhance the efficiency in bonding a filmy solder resist without loosing the positional precision of the solder resist. SOLUTION: For manufacturing a TAB tape by bonding a metal foil to one face or both faces of a tape base material 1 made of an insulating film to form it into a wiring pattern 3 by photoetching, and by forming an insulating film in a region on the wiring pattern 3 except an inner lead 4 and an outer lead 5, a tapelike cover coat material is punched into a filmy cover coat material 20 of a necessary areal form enough to form the above-mentioned insulating film and bonded onto the above-mentioned wiring pattern 3 simultaneously with punching.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a TAB (Tape Aut)
The present invention relates to a method for producing an OMated tape, particularly a TAB tape provided with an insulating film as a surface protective coating layer.

[0002]

2. Description of the Related Art Recently, a liquid crystal display (LCD) has been developed.
As the market expands, the demand for TAB tapes for mounting the driving LSIs is also increasing rapidly. Liquid crystal displays tend to have higher precision, and TAB tapes are also rapidly becoming lighter and thinner.

[0003] The TAB is a mounting method developed for efficiently mounting a highly integrated IC, and continuously mounts the IC on a long TAB tape carrier (TAB tape). Recently, not only liquid crystal panels but also TAB tapes for CSP (Chip Scale Package) have attracted attention.

FIG. 6 shows the surface structure of a conventional TAB tape for a liquid crystal panel.

A method of manufacturing this TAB tape 10 is as follows. First, a wiring pattern 3 is formed on one or both sides of a tape base 1 made of an insulating film made of polyimide resin or the like via an adhesive 2.
Paste copper foil. Then, a device hole 6 serving as an element mounting portion, a perforation hole 7 serving as a feed hole, an outer lead hole 8 and the like are punched out by punching. Next, a predetermined wiring pattern 3 including the signal layer 3a is formed on the surface of the copper foil of the copper foil adhesive tape by photoetching. Specifically, a photoresist is coated, pre-cured, exposed and developed, and post-cured.
The wiring pattern 3 is formed by etching the copper foil.

Next, a solder resist 9 is applied as an insulating film to a portion of the wiring body tape other than the inner leads 4 and the outer leads 5 of the wiring pattern 3.
That is, a liquid photo solder resist or an epoxy solder resist is print-coated, exposed, developed or post-baked to form an insulating surface protective coat layer on the wiring. Thereafter, a plating layer of Sn, Au, or the like is formed on a portion where the solder resist 9 is not formed, that is, on the inner lead 4 and the outer lead 5.

[0007]

As described above, the surface protective coating layer of the TAB tape is generally formed by applying a liquid epoxy solder resist (ink) having an insulating property by a screen printing method, and then applying the ink to a post cure ( After curing, the thickness is Cu
20 μm or less is applied as a target on the wiring.

However, since a liquid solder resist is used, FIG.
As indicated by 1, the end of the solder resist 9 applied to the printing position 92 flows out, and the formation position of the surface protection coat layer with respect to the wiring pattern 3 is shifted from a predetermined formation region, that is, the so-called dimensional tolerance is deviated. Will be. For this reason, if the solder resist 9 serving as the surface protection coat layer is formed up to, for example, the joint portion of the outer lead 5, at the time of mounting on the liquid crystal panel, the ITO electrode of the liquid crystal panel is interposed through the anisotropic conductive film. When connecting the output outer lead 5, a surface protective coating layer enters between the joints between the anisotropic conductive film and the output outer lead 5, which causes a connection failure.

Further, since the coating is performed using the screen printing method, depending on the Cu pattern, the thickness cannot be made uniform, and the Cu wiring is exposed as shown by a wiring exposed portion 93 in FIG. If the wiring pattern 3 is exposed as described above, it may cause a short circuit failure due to a conductive foreign substance or the like after mounting.

Further, since post-curing is performed, the solder resist-coated portion after drying is largely warped due to heat shrinkage. In particular, when the wiring pitch is 80 μm or less, the warpage of the TAB tape is large, and the productivity of mounting the TAB tape for a liquid crystal panel or CSP is low.

[0011] These problems result from the use of a liquid solder resist. Therefore, as a solution to this, as disclosed in Japanese Patent Application Laid-Open No. 5-183013, a film-shaped solder resist having a required area around the device hole excluding the inner lead and the outer lead is attached. Conceivable. According to the method of attaching the film-shaped solder resist, the solder resist does not flow into the solder resist and does not bleed, making it easier for the solder resist to enter fine wiring sections, making the solder resist work easier and requiring an amount of solder resist. Can be minimized. Furthermore, regarding the positional accuracy of the solder resist, the positional accuracy in the conventional screen printing is ±
An advantage is obtained that the thickness is 0.3 mm, which can be greatly improved to within ± 0.05 mm.

However, since the sticking method is performed by normal heat sticking, the production efficiency is low.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a method of manufacturing a TAB tape capable of increasing the efficiency of the operation of attaching a film-shaped solder resist without lowering the positional accuracy of the solder resist. It is in.

[0014]

Means for Solving the Problems In order to achieve the above object, the present invention is configured as follows.

(1) According to the first aspect of the present invention, a wiring pattern is formed by photoetching by attaching a metal foil to one or both surfaces of a tape base made of an insulating film, and inner leads on the wiring pattern are formed. In the method of manufacturing a TAB tape, in which an insulating film is formed in a region excluding outer leads, the insulating film is formed by punching a tape-shaped cover coating material into a required area shape, and forming the punched film-shaped cover coating. This is performed by bonding a material onto the wiring pattern at the same time as punching.

This manufacturing method presupposes the following modes. The first is an adhesive-less single-sided copper-clad single layer C
This is a form in which a metal foil is stuck to one or both sides of a tape base material without an adhesive, such as CL (Copper Clad Laminate) or a double-sided copper-clad two-layer CCL without an adhesive. Second,
This is a form in which a metal foil is attached to one or both sides of a tape base material using an adhesive, such as a single-sided copper-clad single-layer CCL using an adhesive or a double-sided copper-clad two-layer CCL using an adhesive.

Further, the manufacturing method of the present invention includes both a mode having a device hole and a mode having no device hole. In the former case, a metal foil is bonded to one or both sides of a tape base made of an insulating film with or without an adhesive to form a wiring pattern by photoetching, and inner leads on the wiring pattern are formed. The present invention relates to a method for manufacturing a TAB tape in which an insulating film is formed in a shape of a necessary area around a device hole excluding outer leads.

In any form, according to the present invention,
Using the tape-shaped cover coat material as described above, punching this into a sheet, and bonding the punched film-shaped cover coat material at the same time as punching, punching and bonding in separate steps. , A TAB tape with an insulating film can be manufactured more efficiently.

Further, since the wiring pattern is covered with a film-form cover coat material in advance, the thickness can be made uniform and the exposure of the wiring can be prevented as compared with a case where a liquid solder resist is applied by a printing method. can do. In addition, since the film-like cover coat material is adhered, there is no outflow as in the case of applying a liquid solder resist, and the dimensional tolerance is less shifted.

The tape-shaped cover coat material is, for example, an epoxy-based or polyimide-based solder resist, or a photosensitive epoxy acrylate or fluorene-based material which is cured by post-baking at 200 ° C. or less.

(2) The invention described in claim 2 is the first invention.
The manufacturing method described above is characterized in that a hole serving as a solder ball via is previously formed in the tape-shaped cover coating material, and the hole is punched into a predetermined shape, and is bonded at the same time.

The feature of this manufacturing method is that BGA (Ball Gri
d Array) is suitable for manufacturing TAB tapes for CSP semiconductor devices. According to this feature, the purpose of leaving an insulating film unattached to a solder ball via portion in a wiring pattern region can be easily achieved. Can be achieved.

(3) The invention according to claim 3 is the invention according to claim 1.
Or in the manufacturing method according to 2, after the laminating of the film-like cover coat material, a hardening treatment is applied to the cover coat material, and then Sn, Ni, Au are applied to portions of the wiring pattern which are not covered with the cover coat material. And the like.

According to this feature, the amount of heat shrinkage can be suppressed due to the curing treatment (post-curing), so that the warpage and productivity of the TAB tape can be improved.

[0025]

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

FIG. 1 shows a method for producing a TAB tape of the present invention, and FIG. 2 shows a surface structure of a TAB tape for LCD obtained by the method.

This TAB tape is formed by applying or bonding an adhesive 2 (see FIG. 4) to a tape base 1 made of an insulating film such as an organic polyimide tape or a glass epoxy tape, and then punching the perforation holes 7. , An outer lead hole 8 serving as a slit for direct bonding, and a device hole 6. After laminating a copper foil such as a rolled copper foil or an electrolytic copper foil or a metal foil such as an alloy foil, the inner lead 4 for mounting the IC and the outer lead 5 on the input side and the output side are included by a photoresist etching process. It is composed of a predetermined wiring pattern 3 formed. Reference numeral 11 denotes a test pad.

Next, an insulating film is formed as a surface protection coat layer in a required area around the device hole 6 excluding the inner leads 4 and the outer leads 5 on the wiring pattern 3. This step will be described with reference to FIG.

First, a tape-shaped cover coat material (20
An insulating film having a thickness of μm is prepared (FIG. 1A). As the tape-shaped cover coating material, an epoxy-based or polyimide-based solder resist, or a photosensitive epoxy acrylate or fluorene-based material that is cured by post-baking at 200 ° C. or less is used.

Next, a tape-like cover coat material is punched into a required area shape (a frame shape in FIG. 2) (FIG. 1B), and the film-like cover coat material 20 punched into a sheet shape is removed. At the same time as the punching, it is bonded onto the wiring pattern 3 (FIG. 1C). That is, after punching and shearing a tape-shaped cover coat material into a predetermined shape with a punch, the punched film-like cover coat material (insulating film) 20 is lowered as it is, and the wiring pattern is formed using the punching force of the punch. 3 is stuck on as shown in FIG.

Next, a post cure is performed at 180 ° C. (FIG. 1D).
Electroplating or electroless plating of n, Ni, Au or the like is performed (FIG. 1 (e)).

As described above, the LCD TA of the present embodiment
The B tape is manufactured by using a cover coat material in the form of a tape and by sticking a film-like cover coat material 20 obtained by punching the cover coat material into a sheet at the same time as the punching. And TAB tape with an insulating film can be manufactured with higher production efficiency as compared with the case where the steps are performed as separate independent steps.

Further, since the film is coated with the film-like cover coating material 20, the thickness of the insulating film as the surface protective coating layer becomes uniform as shown in FIG. As shown in FIG. 7, since the flow-out (FIG. 7) when the conventional liquid solder resist is used does not occur, the deviation of the actual formation position of the sheet-like cover coat material 20 from the desired formation position of the surface protective coat layer is small. And so-called dimensional tolerances are less likely to shift. It is easy to achieve a positional deviation accuracy of ± 100 μm or less when the cover coat material 20 is bonded simultaneously with punching.

The TAB tape of this embodiment has high insulation resistance and excellent migration resistance.

Further, the TAB tape of this embodiment has a size of 60 μm.
Since there is no outflow of the solder resist with fine wiring of m pitch or less, a slim design is possible and a TAB tape having a structure that is easy to miniaturize can be supplied.

The TAB tape of the present embodiment has improved yield and productivity as compared with the liquid solder resist, and can be stably mass-produced.

<Example 1> A polyimide resin tape base material 1 (with a thickness of 75 μm)
m, width 70 mm), punched perforation holes 7, device holes 6, etc.
Lamination and curing were performed using an 8 μm copper foil tape. The inner leads 4 and the outer leads 5 on the input side and the output side are formed by photo application (exposure / etching) to a thickness of 18 μm of the copper foil on the pattern surface.
Was formed.

Next, a polyimide-based cover coat material (thickness: 20 μm) is punched into a sheet having a predetermined size, and the punched film-like cover coat material 20 is attached to the wiring pattern 3 simultaneously with the punching. Cure 1
Performed at 80 ° C.

Next, in a region of the wiring pattern 3 which is exposed from the resin layer of the film-like cover coating material 20, electroless Sn plating is applied to a thickness of 0.4 μm to obtain a finished TAB tape. .

It was confirmed that the warpage of the completed TAB tape 10 was reduced to 1/3 or less of the case where a conventional liquid polyimide solder resist was used. In addition, there was no exposure of the copper wiring, and the insulation was in a good covering state. Further, the bonding position accuracy was as high as 40 μm or less.

Next, the anti-migration property was measured at 85 ° C. × 85% RH, 3
The test was carried out at 0 V for 1000 hours. It was found that the insulation resistance during the test was high (10 9 Ω or more), stable, and excellent in reliability.

Next, after bonding the semiconductor chip (here, the LSI for driving the LCD), the outer lead bonding of the liquid crystal panel to the printed circuit board using the anisotropic conductive film was performed. The bonding was good and the liquid crystal panel was assembled as a liquid crystal panel. I was able to.

Example 2 A tape substrate 1 (thickness: 50) made of a polyimide tape to which an epoxy-based adhesive was bonded
After punching out perforation holes 7 and the like to a thickness of 35 μm and a width of 35 mm, lamination and curing were performed using a copper foil tape having a thickness of 18 μm. Then, after forming a pattern by a photo application on the copper foil having a thickness of 18 μm on the pattern surface, a copper wiring pattern 3 was formed by etching. Next, a fluorene-based photosensitive cover coating material (thickness: 20 μm) manufactured by Nippon Steel Chemical Co., Ltd. was punched into a sheet having a predetermined size, and the punched film-shaped cover coating material 20 was attached and punched at the same time as the punching, and precured. Thereafter, exposure and development were performed to form a predetermined insulating surface protective coat layer. Thereafter, post cure was performed at 180 ° C. Next, the electroless Sn plating was applied to the region of the wiring pattern 3 which was not covered with the film-like cover coat material 20 and was exposed from the cover coat resin layer to a thickness of 0.4 μm to obtain a finished product.

The obtained TAB tape 10 was good without any copper wiring being exposed. Further, the positional accuracy of the insulating film of the surface protective coating layer was as high as 10 μm or less.

Next, a semiconductor chip (LSI for driving LCD)
After flip chip bonding, outer lead bonding of the liquid crystal panel to the printed circuit board using an anisotropic conductive film was performed, but the bonding was good and the liquid crystal panel could be assembled.

<Modification> In the above embodiment, the tape base 1
A TAB tape having a form in which a metal foil is adhered to an adhesive via an adhesive has been described. However, the present invention is not limited to this, and an adhesive-less double-sided inner lead bonding type and a wire bonding type TAB are used.
It is also possible to apply to B tape. In the case of this double-sided wiring, a cover coat material is stuck on both sides.

The adhesive-free double-sided copper-applied polyimide or glass epoxy tape is composed of copper foil / polyimide tape / copper foil of 9 to 35 μm / 25 to 1 μm.
Those having a range of 50 μm / 9 to 35 μm are suitable. This is because these materials are generally available as a commercial product of an adhesive-less double-sided copper-clad polyimide tape.

In addition, the TAB tape of the present invention has a tape warpage that is as small as one-third that of a conventional liquid solder resist, has high insulation resistance, and has excellent migration resistance. The present invention can also be applied to flip-chip connection without device holes (with a pitch of 50 μm or less) and for beam lead type liquid crystal display (LCD) with device holes.

Further, in the above embodiment, the TA for the liquid crystal panel is used.
The B tape was described as an example. However, as shown in FIG.
A hole (Via Hole) 12 of ~ 800 μm is opened in advance,
The cover coat material 20 is punched into a predetermined shape so that the holes 12 are present in a predetermined positional relationship, and are simultaneously bonded to form a TAB tape 13 for a BGA semiconductor device.
You can also get Also in this embodiment, after performing a hardening process if necessary, plating of Sn, Ni, Au or the like is performed.

[0050]

As described above, according to the present invention, the following excellent effects can be obtained.

(1) According to the first to third aspects of the present invention, since the tape-shaped cover coat material is used and bonded at the same time as punching, the punching and bonding can be performed in separate steps. A TAB tape with an insulating film can be manufactured more efficiently than in the case where the process is performed.

Further, since the wiring pattern is covered with the film-like cover coating material, a uniform insulating film layer can be obtained without exposing the copper wiring, so that the liquid crystal panel and the outer lead for output are joined by the anisotropic conductive film. In this case, it is possible to avoid the inconvenience that the surface protection coat layer enters during that time to cause a connection failure.

Further, since a cover coat material is punched out at a necessary portion and is simultaneously attached, it is easy to form the surface protective coat layer of the wiring pattern so as not to be shifted from a predetermined formation area. It is possible to supply a TAB tape with stable dimensional accuracy and low warpage, which does not cause a so-called dimensional tolerance to be deviated.

(2) According to the second aspect of the present invention, a hole which becomes a solder ball via is previously formed in the tape-shaped cover coat material, and the hole is punched into a predetermined shape and bonded at the same time. T for CSP semiconductor device with structure
In the production of AB tape, of the wiring pattern area,
The purpose of leaving the solder ball via portion without attaching an insulating film can be easily achieved.

(3) According to the third aspect of the invention, after the film-like cover coat material is bonded, the cover coat material is subjected to a curing treatment, so that the heat shrinkage can be suppressed.
It is possible to improve the warpage and productivity of the B tape.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for producing a TAB tape of the present invention.

FIG. 2 is a plan view (pattern surface) showing an embodiment of the present invention.

FIG. 3 is an explanatory diagram of positional accuracy of a resist according to the embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a TAB tape showing an embodiment of the present invention.

FIG. 5 is a partial cross-sectional view of a TAB tape showing another embodiment of the present invention.

FIG. 6 is a plan view of a conventional TAB tape.

FIG. 7 is an explanatory diagram of a flow of solder resist in a conventional TAB tape.

FIG. 8 is a partial cross-sectional view of a conventional TAB tape.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tape base which consists of an insulating film 2 Adhesive 3 Wiring pattern 4 Inner lead 5 Outer lead 6 Device hole 7 Perforation hole 8 Outer lead hole 9 Solder resist 10 TAB tape 12 Hole which becomes a solder ball via 13 TAB tape for BGA 20 Film form Cover coat material

Claims (3)

[Claims] 1. A wiring pattern is formed by photo-etching by bonding a metal foil to one or both sides of a tape base made of an insulating film, and an insulating film is formed on a region of the wiring pattern excluding inner leads and outer leads. In the method of manufacturing a TAB tape, the insulating film is formed by punching a tape-like cover coat material into a required area shape, and simultaneously punching the punched film-like cover coat material onto the wiring pattern. A method for producing a TAB tape, characterized in that the method is performed by laminating the TAB tape. 2. The TAB according to claim 1, wherein a hole to be used as a solder ball via is previously formed in said tape-shaped cover coating material, and is punched into a predetermined shape, and is simultaneously bonded. Tape manufacturing method. 3. The method according to claim 1, wherein
After laminating the film-like cover coat material, the cover coat material is subjected to a hardening treatment, and then Sn, Ni,
A method for producing a TAB tape, comprising plating with Au or the like.