JPH0766931B2 - TAB tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a TAB (Tape Automated Bonding) method that is attracting attention in the process of assembling semiconductor devices, in order to increase the number of pins of the device, reduce the size of the device, and mount the device in high density. A tape having a multilayer structure of a protective layer, a multilayer adhesive layer and an organic insulating film used for the following (hereinafter referred to as TAB tape)
Regarding

[Conventional technology]

Conventionally, the TAB tape is processed as follows to form a film carrier tape.

1) Drill sprocket device holes by stamping.

2) After the copper foil is thermocompression bonded to the punched tape, the adhesive is cured by heating.

3) Apply a photoresist, irradiate with ultraviolet rays through a mask, and then develop.

4) Line the device hole, etch copper, remove the resist, remove the line, make a circuit, and apply solder resist.

5) Perform tin and gold plating.

After the chip is inner lead bonded to the tape produced through the above steps, the lead is cut, outer lead bonding is performed on a printed board or the like, and the tape is sealed with resin. Alternatively, after inner lead bonding,
Seal with resin, cut peripheral circuits, and perform outer lead bonding.

The adhesive and the organic insulating film often remain in the peripheral circuit and the sealing resin. In such a case, as the density becomes higher and higher, ionic impurities that affect the insulation reliability between the patterns of the copper foil and the corrosion of the Al wiring of the chip become a problem. Insulation reliability and ionic impurities are mainly due to the characteristics of the adhesive. That is, the ionic impurities are, in the above steps 3) to 5), that the adhesive is alkali (for example, containing potassium ions during gold plating or resist stripping), acid (for example, chlorine ions or sulfate ions during tin plating). May be contained in the adhesive itself, or may be contained in the adhesive itself. Also, the insulation reliability is governed by the moist heat resistance of the adhesive, the electrical resistance, the ionic impurities, and the like.

The adhesive layer of the TAB tape that has been used in the past is of epoxy type. It is a) that ionic impurities (particularly C1 ions) are easily contained during processing, and b) it is hydrolyzed by wet heat. Due to the properties such as easy, c) low electric resistance, etc., insulation deterioration is a problem including metal transfer between patterns.

The adhesive used for the TAB tape is C, which is a metal.
Since it forms the interlayer between the u foil and the organic insulating film, it is required to have high adhesive strength to both the metal and the organic insulating film.

The adhesive layers of the TAB tapes that have been used conventionally have a single-layer structure.
a) In the above step, the adhesive layer is alkali (for example, during gold plating or resist stripping), acid (for example, tin plating),
There are drawbacks such as a decrease in the adhesive strength to Cu foil due to exposure to etching liquid, and b) a decrease in the adhesive strength to the organic insulating film at high temperature during inner lead and outer lead bonding. As the density and the number of pins increase, the problems such as bonding mistakes of multi-pin chips, lead deformation, and peeling are becoming problems.
The present invention aims to solve the above-mentioned problems in the conventional TAB tape.

[Means for Solving the Problems]

The tape for TAB of the present invention comprises an adhesive layer and a protective layer provided on an organic insulating film, the adhesive layer is composed of at least two layers, and the adhesive layer on the side in contact with the organic insulating film is The polyamide resin is the main component, and the adhesive layer on the side in contact with the protective layer is characterized in that the polyamide resin and the resol-type phenol resin are the main components.

FIG. 1 is a schematic cross-sectional view of a TAB tape of the present invention, which is a semi-cured adhesive consisting of a first adhesive layer 21 and a second adhesive layer 22 on one side of an organic insulating film 1. Layer 2 and
It has a layer structure in which protective films 3 to be protective layers are sequentially laminated. In the figure, the adhesive layer 2 has a two-layer structure, but in the present invention, it may have a layer structure of two or more layers.

The organic insulating film has a thickness of 25 to 188 μm, preferably 50 to 125 μm of polyimide, polyetherimide,
An organic insulating film made of a heat-resistant film such as polyphenylene sulfide or polyether ether ketone or a composite heat-resistant film such as epoxy resin-glass cloth or epoxy resin-polyimide-glass cloth can be used.

The adhesive layer is a thermosetting type and needs to be semi-cured, and is composed of at least two layers. The total thickness of the adhesive layer is in the range of 10 to 50 μm, preferably 15 to 30 μm. Further, it is desirable that the adhesive layer on the side in contact with the organic insulating film and the adhesive layer on the side in contact with the protective layer each have a film thickness of at least 1 μm.

Of the adhesive layers, the adhesive layer on the side in contact with the organic insulating film is in direct contact with the organic insulating film, and thus has high adhesiveness even at high temperatures and exhibits high adhesive strength with the organic insulating film. Adhesive is used. As such an adhesive, in the present invention, an adhesive containing a polyamide resin as a main component is used. An epoxy resin or a novolac type phenol resin can be used in combination with this adhesive layer in order to impart chemical resistance. Furthermore, it is possible to blend a thermoplastic resin such as polyester resin, NBR or SBR. In any case, the polyamide layer is preferably contained in the adhesive layer which is in direct contact with the organic insulating film in an amount of 50% by weight or more.

When the content of polyamide resin becomes lower than 50% by weight,
The adhesive strength of the adhesive layer to the organic insulating film becomes weak, and there is a phenomenon that peeling occurs at the interface between the adhesive layer and the organic insulating film due to the TAB tape processing step and bending when used as a film carrier tape after processing. , Causing a serious decrease in reliability of semiconductor devices. Further, the pattern of the copper foil is easily peeled off from the organic insulating film during bonding, which causes a problem that the reliability of the semiconductor device is deteriorated similarly to the above.

On the other hand, the adhesive layer on the side in contact with the protective film comes into contact with the copper foil during processing into the film carrier tape, and therefore has high adhesiveness with the copper foil and a chemical solution exposed during processing into the film carrier. Adhesives with excellent chemical resistance are used. In the present invention, as such an adhesive, one having a polyamide resin and a resol-type phenol resin as main components is used.

In this adhesive layer, the ratio of the polyamide resin and the resole-type phenol resin is preferably in the range of 4 to 100 parts by weight of the resole-type phenol resin with respect to 100 parts by weight of the polyamide resin, and the polyamide resin is It is preferably less than 50% by weight of the total adhesive.

When the content of the polyamide resin is 50% by weight or more, the heat resistance of the adhesive layer decreases, and the insulation resistance decreases or fluctuates in the high temperature atmosphere (for example, the temperature of 70 to 80 ° C during tin plating). And the semiconductor device malfunctions. Further, the chemical resistance of the adhesive layer is lowered, and the adhesive layer is deteriorated by being exposed to a strong alkali during gold plating or resist stripping, or exposed to a strong acid during tin plating, or an etching solution. And the adhesive strength with the copper foil decreases. These chemicals are more likely to be absorbed as impurities in the adhesive layer, reducing the electrical reliability and causing the semiconductor device to malfunction similarly to the above.

In addition, a thermosetting resin such as an epoxy resin or a novolac type phenol resin, and a curing accelerator such as imidazole can be used in combination with this adhesive layer.

As the polyamide resin used in each of the adhesive layers in the present invention, various known ones can be used.

The molecular weight of the polyamide resin used is related to flexibility, melting characteristics when the tape and copper foil are thermocompression-bonded, and when the adhesive cures (extrusion of the adhesive from the device hole). If is too low, the melting temperature will be low and the problem of protrusion will occur. Further, if the molecular weight is too high, there arises a problem that the thermocompression bonding temperature with the copper foil becomes too high. Therefore, in the present invention, a molecular weight of 30,0
It is preferable to use a polyamide resin having a softening temperature of 100 to 180 ° C. in the range of 00 to 150,000.

Furthermore, there is a molecular weight distribution as a factor that influences the melting characteristics related to the protrusion of the adhesive from the device hole, and when the molecular weight distribution is narrow, a rapid decrease in viscosity due to heat occurs and the tape and copper foil It is not preferable because the heat and pressure conditions that do not cause protrusion from the device hole during heat and pressure are narrow. Therefore, the polyamide resin used in the present invention preferably has a wide molecular weight distribution.

When a polyamide resin having an amide group equivalent (molecular weight / one amide group) of 200 to 400 is used as the polyamide resin, the hygroscopicity of the adhesive layer becomes low, and
It is particularly preferable because the decrease in electric resistance due to moisture absorption can be suppressed to about one digit, the moisture resistance such as hydrolysis is improved, and the insulation deterioration can be prevented as a result.

Polyamide resin has a wide range of molecular weight of hydrocarbons between amide groups from 100 to 800 in one molecular chain, and hydrocarbon molecules between amide groups having different molecular weights are randomly arranged. You may use the thing.
These polyamide resins are preferably used because they have adhesiveness and flexibility even though the amide group equivalent is large.

As the resole-type phenol resin used in combination with the above polyamide resin, a bisphenol A type, an alkylphenol type, or a cocondensation type thereof in which the phenol component is one or two selected from bisphenol A and alkylphenol can be used. Examples of the alkylphenol type resol type phenolic resin include those having a methyl group, an ethyl group, a propyl group, a t-butyl group, a nonyl group or the like at the o- or p-position of the phenolic aqueous group. The resol type phenol resin reacts by heating to become an insoluble and infusible solid having an adhesive force, and acts to improve the adhesive force, insulation reliability, chemical resistance, and heat resistance of the adhesive.

A film made of polyethylene, polyethylene terephthalate, polypropylene, or the like can be used as a protective film for the protective layer of the adhesive layer. Next, a method for producing the TAB tape of the present invention will be described. FIG. 2 shows the manufacturing process, and the protective film 3
First, two kinds of adhesives having a predetermined composition are applied so that the film thickness after drying falls within the above range.
The adhesive layer 21 and the second adhesive layer 22 are formed, or a film composed of two kinds of adhesives formed in advance into a single layer is laminated on the protective film 3 by thermocompression bonding. At this time, the heating condition is 15 to obtain a semi-cured state.
It is necessary to dry at 0-180 ° C.

Next, the organic insulating film 1 is superposed on the surface of the formed adhesive layer 2 and thermocompression-bonded at 100 to 130 ° C. under the condition of 1 kg / cm ² or more.

The obtained TAB tape is wound, for example, width 30-200mm
The length of 30-300m can be obtained.

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

Example 1 A coating film for an adhesive layer having the following composition was applied to a protective film made of a polyethylene terephthalate film having a thickness of 38 μm and dried by heating at 160 ° C. for 2 minutes to form an adhesive layer having a film thickness of 15 μm.

Polyamide resin (Tomide TXC-232-B manufactured by Fuji Kasei Kogyo Co., Ltd.) 25% isopropyl alcohol / water mixed solution 60 parts Resol phenol resin (CKM-1282, Showa Polymer Co., Ltd.) 50% methyl ethyl ketone solution 6 parts Epoxy resin ( Epicoat 828, Yuka Shell Co., Ltd.) 14 parts Novolac phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 14 parts 2-Ethylimidazole 1% methyl ethyl ketone solution
10 parts Next, an adhesive layer coating composition having the following composition was applied onto the adhesive layer and dried at 160 ° C. for 2 minutes to form an adhesive layer having a film thickness of 5 μm.

25% isopropyl alcohol / water mixed solution of polyamide resin (Tomide TXC-232-B manufactured by Fuji Kasei Kogyo Co., Ltd.) 100
Part Epoxy resin (Epicoat 828, Yuka Shell Co., Ltd.) 8 parts Novolac phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 2 parts 1% methyl ethyl ketone solution of 2-ethylimidazole 10 parts Polyimide with a thickness of 50 μm Organic insulating films made of films were stacked and heated and pressed under the conditions of 130 ° C. and 1 kg / cm ² to prepare a TAB tape.

Next, the protective film of this TAB tape was peeled off, 1 ounce electrolytic copper foil (thickness 35-40 μm) was attached, and
The heating and pressurizing treatment was performed under the conditions of ℃ and 1 kg / cm ² . After that, 60 ° C for 6 hours, 80 ° C for 6 hours, 120 ° C for 3 hours, and 1
Each adhesive layer was cured by sequentially heating at 50 ° C. for 5 hours. Further, a photoresist film was formed on the copper foil by a conventional method and treated, and the copper foil was etched to form a comb-shaped circuit to prepare a film carrier tape.

Example 2 A TAB tape and a film carrier tape were produced in the same manner as in Example 1 except that the adhesive layer coating material having the following composition was used.

(Adhesive on protective film side) Polyamide resin (Macromelt 6212 Henkel Hakusui Co., Ltd.) 25% isopropyl alcohol / water mixed solution 60 parts Resol phenol resin (CKM-1282, Showa Polymer Co., Ltd.) 50% methyl ethyl ketone solution 6 Part Epoxy resin (Epicoat 828, Yuka Shell Co., Ltd.) 14 parts Novorask phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 2-ethyl imidazole 1% methyl ethyl ketone solution 10 parts (on the organic insulating film side) Adhesive) Polyamide resin (Macromelt 6212 Henkel Hakusui Co., Ltd.) 25% isopropyl alcohol / water mixed solution 100 parts Epoxy resin (Epicoat 828, Yuka Shell Co., Ltd.) 8 parts Novolac phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) ) 50% methyl ethyl ketone solution 8 parts 2-ethyl imidazole 1 Methyl ethyl ketone solution
10 parts Example 3 A TAB tape and a film carrier tape were produced in the same manner as in Example 1 except that the adhesive layer coating material having the following composition was used.

(Adhesive on protective film side) 25% isopropyl alcohol / water mixed solution of polyamide resin (Platabonda M-1276, manufactured by Rilsan Japan) 60 parts Resol phenol resin (PR-11078, manufactured by Sumitomo Durez) 50% methyl ethyl kent Solution 6 parts Epoxy resin (Epicoat 828, Yuka Shell Co., Ltd.) 14 parts Novolac phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 14 parts 2-Ethylimidazole 1% methyl ethyl ketone solution
10 parts (adhesive for the organic insulating film) 25% isopropyl alcohol / water mixed solution of polyamide resin (Platabonda M-1276 manufactured by Rilsan Japan) 100 parts Epoxy resin (Epicoat 828, Yuka Shell Co.) 8 parts Novolac phenol Resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 8 parts 2-ethyl imidazole 1% methyl ethyl ketone solution
10 parts Comparative Example 1 A film carrier tape was produced in the same manner as in Example 1 except that the adhesive layer coating material having the following composition was used and the adhesive layer had a single-layer structure to produce a TAB tape.

Polyamide resin (Tomide TXC-232-B manufactured by Fuji Kasei Kogyo Co., Ltd.) 25% isopropyl alcohol / water mixed solution 60 parts Resol phenol resin (CKM-1282, Showa Polymer Co., Ltd.) 50% methyl ethyl ketone solution 6 parts Epoxy resin ( Epicoat 828, Yuka Shell Co., Ltd.) 14 parts Novolac phenolic resin (Tamanor 752, Arakawa Chemical Co., Ltd.) 50% methyl ethyl ketone solution 14 parts 2-Ethylimidazole 1% methyl ethyl ketone solution
10 parts Comparative Example 2 A film carrier tape was produced in the same manner as in Example 1 except that the adhesive layer coating material having the following composition was used and the adhesive layer had a single-layer structure to produce a TAB tape.

Polyamide resin (Platabonda M-1276, manufactured by Rilsan Japan) isopropyl alcohol / water mixed solution 100 parts Epoxy resin (Epicoat 828, manufactured by Yuka Shell Co., Ltd.) 8 parts Novolac phenolic resin (Tamanor 752, manufactured by Arakawa Chemical Co., Ltd.) 8 parts 2-Ethylimidazole 1% methyl ethyl ketone solution
10 Parts (Characteristic Evaluation Test) The film carrier tapes of Examples 1 to 3 and Comparative Examples 1 and 2 were subjected to the following characteristic evaluation test.

1. Chemical resistance test In order to investigate the adhesive force between the copper foil and the adhesive layer when immersed in the etching solution and the electroless plating solution, the pattern width of 200 μm, 100 μm and 50 μm was formed by etching. The adhesive force of the copper foil pattern was measured, and the adhesive force after electroless plating was measured. The results are shown in Table 1. The numerical values in Table 1 are values obtained by measuring 180 ° peeling force with a Tensilon tensile strength measuring machine.

2. Heat-resistant adhesive property 3 cm of film carrier tape with 1 cm width Cu foil formed
The organic insulating film was fixed on a hot plate at 50 ° C so that the back surface of the organic insulating film was in contact, and the Cu foil was peeled at a peeling speed of 5 cm / min in the direction of 180 °, and the peeling force at that time was measured. The results are shown in Table 2.

As is clear from the results of Table 1 and Table 2,
The above test confirmed that the TAB tape exhibited excellent chemical resistance and heat-resistant adhesiveness.

〔The invention's effect〕

In the TAB tape of the present invention, the adhesive layer has a laminated structure of two or more layers, and the adhesive layer on the side in contact with the organic insulating film and the adhesive layer on the side in contact with the protective layer have the above-mentioned adhesion. Since it has an agent composition, even if the adhesive is exposed to an alkali, an acid, an etching solution, or the like during processing steps such as etching, plating, and resist stripping, the adhesive strength to the Cu foil does not decrease. Further, the adhesive strength to the organic insulating film does not decrease under high temperature during the inner lead and outer lead bonding.

Therefore, the TAB tape of the present invention can be applied to a high-density circuit. Further, the tape for TAB of the present invention has high insulation reliability and does not cause a problem in insulation between leads. Therefore, when used for connection between a chip and an external circuit, even if the number of leads increases, The tape can be left on the lead portion. Therefore, when a multi-pin chip is mounted, bonding mistakes are less likely to occur, and lead deformation is small in the carrying process, the bonding process, etc., and the yield is greatly increased.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of the TAB tape of the present invention,
FIG. 2 is a manufacturing process drawing of the TAB tape of the present invention. 1 ... Organic insulating film, 2 ... Adhesive layer, 21 ... First
Adhesive layer of 22 ... Second adhesive layer, 3 ... Protective film.

Claims (3)

[Claims] An adhesive layer and a protective layer are provided on an organic insulating film, the adhesive layer is composed of at least two layers, and the adhesive layer on the side in contact with the organic insulating film is a polyamide resin. Is a main component, and the adhesive layer on the side in contact with the protective layer is mainly composed of a polyamide resin and a resol-type phenolic resin. 2. The tape for TAB according to claim 1, wherein the content of the polyamide resin in the adhesive layer on the side in contact with the organic insulating film is 50% by weight or more. 3. The TAB tape according to claim 1, wherein the content of the polyamide resin in the adhesive layer on the side in contact with the protective layer is less than 50% by weight.