JPH07153799A - Method of manufacturing of double-layer tab tape - Google Patents

Abstract

PURPOSE:A double-layer TAB is manufactured easily and economically by forming holes in a film not heat-treated and dried up to the temperature to complete imidizing, keeping it in a state of a half-cured polyamino acid film with openings, press adhering the film to a conductive layer wider than the film and forming conductors by completing the imidizing. CONSTITUTION:Predetermined openings as device holes are formed on a half- cured polyamino acid film. The film is press adhered to a conductive foil that is wider 0.2mm or more exposing the conductor foil by 0.1mm or more at both sides. By heat-treating it, imidizing is completed. A predetermined pattern is formed by etching the conductor foil. With this, a 2 layer TAB is obtained in which device holes are provided by punching and the 2 layer TAB made from rolled foil, that is not usable with the vacuum deposition method, is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a T for mounting a semiconductor element.
The present invention relates to a method for manufacturing an AB (Tape Automated Bonding) tape, and more particularly to a method for manufacturing a double-layer TAB tape.

[0002]

2. Description of the Related Art Although semiconductor packaging technology has made remarkable progress in recent years, TAB, in particular, can easily cope with an increase in the number of pins because a conductor pattern can be formed with extremely high density, and a wire is used for bonding. Since it is possible to wire-connect the entire lead to the semiconductor element at a time without incident, high-density mounting technology is currently required, and development is actively underway.

There are two types of TAB tapes, a two-layer structure and a three-layer structure. The three-layer structure (hereinafter abbreviated as three-layer TAB) generally has a conductor foil such as copper foil and a heat-resistant resin film. It is made by sticking together with an adhesive, and even if a polyimide film with excellent properties such as heat resistance and chemical resistance is used as a film, it has an adhesive layer with poor heat resistance, so it is possible to make full use of that property. There wasn't.

On the other hand, a two-layer structure TAB (hereinafter abbreviated as two-layer TAB) is generally excellent in heat resistance as a TAB because it does not have an adhesive layer on the base film, but is practically used because of its difficult manufacturing method. It was rarely offered. That is, as a method for manufacturing a two-layer TAB, a conductor layer is provided on a heat-resistant film such as polyimide by using a thin film forming technique such as sputtering, vapor deposition, and plating, and then etching treatment is performed on the base film and the conductor layer to form device holes and A method of forming a predetermined opening such as a sprocket hole and a conductor pattern, and a varnish of a heat-resistant resin such as polyimide is directly applied on a conductor foil such as a copper foil and dried to form a two-layer substrate, and then a resin layer and a conductor foil. It is manufactured by two kinds of methods, that is, a method for forming a predetermined opening portion or a conductor pattern by performing an etching treatment on the. In the former, a rolled foil having excellent flexibility and a Fe-Ni alloy foil having excellent strength are used. Since it is necessary to use the etching method to form the openings in the base film, it is not possible to use a 3-layer TAB. Productivity as compared to come method significantly decreases. On the other hand, also in the latter, in order to prevent the occurrence of curls and wrinkles, it is necessary to match the linear expansion coefficient of the resin used with that of the copper foil which is the conductor layer, but such a resin is generally rigid and excellent in solvent resistance. Therefore, alkali etching is difficult in many cases, and dry etching such as excimer laser must be performed to provide an opening in the film layer, which is disadvantageous in productivity and cost. .

Further, most of these problems can be solved by using a method in which holes are formed in the polyamic acid film, thermocompression bonding is performed on the conductor foil, and then baking is performed, but most of these problems are solved. When a copper foil narrower than the width is thermocompression-bonded and fired, the polyamic acid film will be fired in a free state without a support, and the part that is not pressure-bonded to the copper foil will be wrinkled like wakame. It was a problem.

[0006]

The object of the present invention is to produce a two-layer TAB having no adhesive layer, after the polyamic acid film is pressure-bonded to a conductor foil wider than the polyamic acid film, the imide is used. The present invention provides a method for producing a two-layer TAB with excellent productivity without impairing dimensional stability, smoothness, and the like.

[0007]

According to the present invention, a semi-cured polyamic acid film is provided with a predetermined opening such as a device hole, and then both end portions are formed on a conductor foil having a width of 0.2 mm or more wider than the film. From the above, the film is pressure-bonded so that the conductor foil is exposed by 0.1 mm or more, and the imidization is completed by heat treatment, and then the conductor foil is subjected to etching treatment or the like to form a desired pattern. It is a method of manufacturing a two-layer TAB tape.

In the method for producing a semi-cured polyamic acid film in the present invention, a polyamic acid solution is applied onto a release film and dried until a tack-free state is formed to form a polyamic acid film. Further, another polyamic acid film having the same composition or a different composition is aligned with the polyamic acid film surface, and if necessary, a predetermined number of polyamic acid films are inserted between them, and two or more sheets are simultaneously heated and pressure-bonded to form a thick polyamic acid film. You can also do it.

Next, the polyamic acid film is perforated by a usual method, for example, punching, cutting, alkali etching, laser or the like together with the release film, or by perforating only the polyamic acid film.
Punching is preferable in terms of cost.

The polyamic acid film which has been subjected to the hole processing is sufficiently imidized after being heated and pressure-bonded to the conductor foil. Next, a conductor pattern is formed. At this time, the conductor foil having a width wider than that of the polyamic acid film by 0.2 mm or more is crimped so that the conductor foil is exposed by 0.1 mm or more from both ends. Generally, the slit accuracy of the film and the alignment accuracy between the film and the conductor foil are both 0.05m.
Since it is about m, if the polyamic acid film is pressure-bonded so that the conductor foil is exposed by 0.1 mm or more, the film will not protrude from the copper foil. On the other hand, like a normal 3-layer TAB, when a copper foil narrower than the width of the resin tape is thermocompression-bonded and fired, the polyamic acid film is fired in a free state without a support, so that a portion not pressure-bonded to the copper foil Wrinkles like wakame.

In the present invention, suitable conditions for drying the polyamic acid solution to form a semi-cured polyamic acid film are 80 to 200 ° C. and 5 to 30 minutes. If the temperature is lower than this and the time is short, the fluidity is large when heating and crimping with the conductor foil, bleeding and bleeding at the opening are large, and the variation in the film thickness is large, and the dimensional change after imidization Grows larger. If the temperature is higher and the time is longer than this, the fluidity is too small when heated and pressure-bonded to the conductor foil, the peel strength with the conductor foil decreases, and voids increase. The coating thickness of the amic acid is preferably 200 μm or less after imidization. When the thickness is thicker than this, the film layer is thick, so that the evaporation rate of the solvent is slow and the productivity is remarkably lowered. The conditions for heating and pressure-bonding the polyamic acid films to each other or to the conductor foil are 70 to 200 ° C., 5 to 100 kg / cm ² , and 5 to 30 minutes in the case of a press type.
In the case of a roll type laminator, 70-200 ° C, 1-50
Suitable conditions are kg / cm and 0.1 to 10 m / min. Especially, the temperature is 1 from the drying temperature of the polyamic acid film.
It is desirable to carry out the reaction at a temperature lower by 0 to 30 ° C. without generating volatile matter.

The polyamic acid in the present invention is usually obtained by reacting a diamine with an acid anhydride.
Examples of the diamine include phenylenediamine, diaminodiphenylmethane, diaminodiphenyl sulfone, and diaminodiphenyl ether, and examples of the acid anhydride include trimellitic anhydride, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, and benzophenonetetracarboxylic acid. It is possible to use dianhydride and the like, one for each
One kind or two or more kinds can be appropriately combined and used. The imidation ratio in the state of the polyamic acid film is preferably 10 to 50%, and desirably 20 to 40%.
If the imidization ratio is less than 10%, not only does tackiness remain and workability is poor, but it also becomes difficult to adhere the film to the back surface of the release film and isolate the films one by one after winding.
When imidization is performed at 0% or more, the melting property deteriorates, and even if the amic acid surfaces are combined and thermocompression bonded, they are not sufficiently integrated.

Materials that can be used as the release film include plastic films such as polypropylene, polyester, polyether sulfone, polyimide and polyethylene.

Examples of materials that can be used as the conductor layer include metal foils such as Fe—Ni alloys and Fe—Cr—Al alloys in addition to simple metal foils such as copper, aluminum and nickel.

[0015]

The present invention provides a semi-cured polyamic acid film having an opening by performing pore processing in the state of a polyamic acid film without heating and drying until it is completely imidized by using an ordinary polyimide film manufacturing apparatus. A double-layer TAB tape can be easily and inexpensively produced with good productivity and yield by taking a step of crimping this film onto a conductor layer wider than a polyamic acid film, completing imidization, and forming a conductor wire. Can be obtained.

[0016]

【Example】

(Example) A 4-neck separable flask equipped with a thermometer, a stirrer, a reflux condenser, and a dry nitrogen gas inlet was charged with 108 g of purified anhydrous paraphenylenediamine and 200 g of 4,4'-diaminodiphenyl ether.
A mixed solvent of 90% by weight of anhydrous N-methyl-2-pyrrolidone and 10% by weight of toluene was added thereto and dissolved in such an amount that the solid content ratio in all the charged raw materials was 20% by weight. Dry nitrogen gas was allowed to flow in all steps from the reaction preparation stage to the product removal. Then, purified anhydrous 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride 2
Although 94 g and 218 g of pyromellitic dianhydride were added little by little with stirring, since this is an exothermic reaction, cold water of about 15 ° C. was circulated in an external water tank to cool it. After the addition, the internal temperature was set to 20 ° C., the mixture was stirred for 5 hours, the reaction was terminated, and a polyamic acid solution was obtained.

This polyamic acid solution was coated on a commercially available polyester film with a bar coater so that the thickness after imidization would be 50 μm, and dried at 130 ° C. for 15 minutes to obtain a polyamic acid film. Slit to the hole and perform hole processing (device hole) using a mold, and roll-type by superposing the polyamic acid film surface so that both ends of the copper foil are exposed by 5 mm on the roughened surface of the commercially available copper foil of 45 mm width. Using a laminator, 110 ℃, 15kg / c
Partial heating and pressure bonding were performed under the conditions of m and 0.5 m / min. After that, remove the release film and heat at 380 ° C for 1 hour,
Imidization was completed to obtain a two-layer substrate having device holes.

Using the obtained two-layer substrate, a conductor pattern is formed by subjecting a conductor foil to a predetermined resist pattern and a hole filling process, and then performing an etching process to form a conductor pattern. 2 by removing and punching a sprocket hole
A layer TAB tape was obtained.

(Comparative Example) The same material as in Example 1 was used except that a commercially available copper foil having a width of 25 mm was used and the surfaces of the polyamic acid film were superposed such that both ends of the polyamic acid film were exposed on the roughened surface by 5 mm. A two-layer substrate having a device hole was produced by the method, and the polyimide film did not have a support (copper foil) because the polyimide film contracted due to desolvation and dehydration condensation reaction during imidization by heating. The edge of the film was wrinkled like wakame.

[0020]

According to the present invention, it is possible to obtain a two-layer TAB having a device hole and excellent in heat resistance, chemical resistance and the like by punching with excellent productivity, and to use in a vapor deposition method or the like. It has become possible to manufacture a two-layer TAB using a rolled foil, which was not possible. INDUSTRIAL APPLICABILITY The present invention can be easily applied to a continuous process using a continuous sheet, and is suitable as an industrial method for producing a two-layer TAB.

Claims (1)

[Claims] 1. A semi-cured polyamic acid film is provided with a predetermined opening, and a conductor foil having a width wider than that of the film by 0.2 mm or more is exposed so that the conductor foil is exposed by 0.1 mm or more from both ends. A method for producing a two-layer TAB tape, characterized in that the film is pressure-bonded to, the imidization is completed, and then a desired pattern is formed on the conductor foil.