JPH10126019A - Flexible printed board, fc tape, and tab(tape automated bonding) tape composed of fc tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a polyimide film to have such water absorption, a coefficient of hygroscopic swelling, and a coefficient of thermal expansion that meet specific conditions by dehydrating and ring-closing a polyamic acid copolymer which is a precursor obtained by performing polymerization in an organic polar solvent by using an acid anhydrite and a diamine component under a substantially equimolar condition. SOLUTION: A polyamic acid film having a self-supporting property is obtained by making to flow and spread or applying a polyamic acid copolymer or its solution on or to the surface of a supporting plate, such an organic film as the PET, etc., or such a support as the drum, endless belt, etc., in a film-like state after a stoichiometric quantity of or more dehydrating agent and a catalytic amount of tertiary amine is added to the copolymer or its solution and evaporating an organic solvent. Then the stripping-off end section of the film from the supporting film is fixed. After fixing the stripping-off end, the polyamidic acid is imidized by gradually heating the film to about 100-500 deg.C and, after cooling the film, the film is stripped off from the supporting plate. Therefore, a polyimide film having water absorption of <=1.6%, a coefficient of hygroscopic swelling of <=15ppm, and a coefficient of expansion of >=1.0×10<-5> deg.C and <=2.5×10<-5> deg.C can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TAB (Tape Automat) which has been attracting attention in the process of assembling a semiconductor device in increasing the number of pins, reducing the size, and mounting the device at a high density.
ed Bonding) Tape (hereinafter referred to as FC) having a three-layer structure of a protective layer, an adhesive layer, and an organic insulating film used in the system.
It is called tape. ), And a TAB tape in which a copper foil is bonded to an FC tape to draw a circuit, and a flexible printed circuit board (hereinafter abbreviated as FPC) which is small in dimensional change with respect to temperature change and small in hygroscopic dimensional change and excellent in heat resistance. .).

[0002]

[Prior art]

[0003] In recent years, flexible printed circuit boards (hereinafter, referred to as FPC) having excellent flexibility have been widely used as printed circuit boards and connection cables in various electronic devices. FPC is a roll-to-roll method for applying a base film, which is a long insulating material, to adhesive coating and drying, laminating copper foil, curing adhesive, and forming an arrangement pattern (resist coating, copper etching, resist stripping). It is manufactured by a processing step. In general, when a pattern is formed, a dimensional change occurs in an etching process. Therefore, when designing a circuit, it is necessary to design the circuit in consideration of changes in subsequent processes in advance.

This dimensional change is caused by dimensional change due to moisture absorption and dehumidification of the base film, which is an insulating material of the FPC, distortion due to a difference in thermal expansion between the copper foil and the base film generated during lamination of the copper foil, and tension generated in each process. Caused by distortion.

Among these, the dimensional change caused by the above can be easily incorporated into the design if the coefficient of thermal expansion of the base film is constant. Also,
The dimensional change due to the cause can be controlled by controlling the tension in each step, and the dimensional change can be easily incorporated into the design.

However, in the manufacturing process of the FPC, a process of absorbing moisture and drying is repeated in a washing process and the like, so that it is difficult to control a dimensional change due to moisture absorption and dehumidification of the base film. .

[0007] A base film which is a conventional insulating material generally has a large hygroscopic expansion coefficient due to its characteristics.
The dimensional change due to moisture absorption and dehumidification in the C production process was large, and was a problem that could not be solved for the above reasons.

In recent years, the number of pins of semiconductor devices has been increased,
As a technology that can respond to miniaturization and high-density mounting, a hole (device hole) for mounting a semiconductor chip such as an LSI is provided on a long insulating film, and a very thin copper foil lead is formed on it. TAB technology for connecting an LSI or the like to a printed wiring board or the like via these leads has attracted attention.
In such TAB technology, generally, a protective layer, an adhesive layer, and an organic insulating film layer (base film layer) are used.
An FC tape having a layered structure is used, and the processing steps up to mounting an LSI or the like on a TAB tape obtained by processing the FC tape are performed as follows.

That is, the processing steps of the TAB tape are as follows:
Steps of forming sprocket holes and device holes by punching, removing protective layers, laminating copper foil, curing adhesives, forming arrangement patterns (resist coating, copper etching, resist peeling), plating This is performed in eight steps of a step, an inner lead bonding step, a resin sealing step, a punching step, and an outer lead bonding step, and the LSI is mounted through the above processing steps.

In order to mount an LSI on a TAB tape,
The steps from the punching step to the plating step are performed under tension. Therefore, when the elastic modulus of the base film is low, elongation occurs and it is difficult to draw a circuit of a fine pattern.

Further, in the processing steps of copper foil laminating, adhesive curing, inner lead bonding, resin sealing, and outer lead bonding, heat is applied, so that it is inconvenient if the base film of the TAB tape has a large thermal expansion coefficient. Occurs. For example, in a processing step of inner lead bonding, a displacement of a bonding position with an LSI occurs due to thermal expansion of a base film. Similarly, in the outer lead bonding process,
The displacement of the joining position between the outer lead and the substrate occurs. If this shift occurs, joining becomes impossible, and the reliability is reduced.

Further, in the copper foil laminating processing step, since the copper foil is heated together with the copper foil, if it exhibits a different thermal behavior from the copper foil, that is, if it has a different thermal expansion coefficient from the copper foil, it causes curling. . When the curl, that is, the warpage of the TAB tape occurs, there is a problem that the electrical connection portion of the bonding is distorted and the electrical reliability of the circuit is reduced.

When the water absorption of the base film is large, the copper foil laminating processing step
Immediately after the curing reaction of the adhesive is completed and taken out of the curing heating furnace, the base film is dried, so it is fixed to the copper foil without distortion, but when the copper foil is left in a laminated state, Due to the nature of the base film, it gradually expands and absorbs moisture with time. However, copper foil does not absorb moisture and expand, and it has high rigidity compared to film and does not cause dimensional change due to film expansion.Therefore, internal stress is applied to the adhesive layer sandwiched between copper foil and film. Will be accumulated.

Therefore, an arrangement pattern forming step in this state (resist coating, copper etching, resist peeling)
In the above, drying and moisture absorption will be repeated, and when a wiring pattern is formed on the copper foil by etching, the stress in the portion where the copper foil has been removed is released by etching, causing a dimensional change, and the wiring pattern is formed. Will be formed. As a result, connection failure with the semiconductor device occurs,
Such a dimensional change has caused a decrease in yield in the TAB processing step.

[0015]

[Problems to be solved by the invention]

In order to solve the above-mentioned problems, in the manufacturing process of the FPC, a dimensional change due to moisture absorption / dehumidification of the base film is controlled. The appearance of the base film was awaited.

Further, in order to solve the above-mentioned problems in the TAB tape manufacturing process, specifically, in the processing step of the TAB tape, and in the processing step of the inner lead bonding, an LSI (silicon wafer) and a base film are formed. It is necessary that the thermal expansion coefficient is close,
In the outer lead bonding process,
The substrate to be bonded and the base film have similar thermal expansion coefficients, and in the copper foil laminating process,
It is required that the copper foil and the base film have similar thermal expansion coefficients. The coefficient of thermal expansion of the LSI is 0.4 × 10 ⁻⁵ ° C. ⁻¹
And the coefficient of thermal expansion of the copper foil is 1.6 × 10 ⁻⁵ ° C. ⁻¹ .

From the above, TAB tape and FP
The base film used for C needs to be a film having a high elastic modulus. In addition, it is necessary to have a low water absorption, and further, the coefficient of thermal expansion is 0.4 × 10 ⁻⁵ ° C. ^-1 .
It is desirably about 2.6 × 10 ⁻⁵ ° C. ⁻¹ . The emergence of a TAB tape using a base film having these properties has been awaited.

An object of the present invention is to solve the above-mentioned problems in the conventional FPC, FC tape and TAB tape comprising the same, and to draw a flexible printed circuit board which does not cause a dimensional change, an FC tape, and a circuit in which a copper foil is bonded thereto. To provide a TAB tape. Accordingly, the present inventors have conducted intensive studies and found that a polyimide copolymer obtained by dehydrating and ring-closing a polyamic acid copolymer having a specific structure in a flexible printed circuit board, or an FC tape and a TAB tape made of the same. By conceiving the use of a polyimide film composed of a united film as a base film, they have found that the above-mentioned conventional problems can be solved and the initial object can be achieved, and the present invention has been completed.

[0020]

[Means for Solving the Problems]

The gist of the flexible printed board according to the present invention is as follows. In a flexible printed board obtained by laminating at least a conductor layer and a base film, the base film has a water absorption of 1.6% or less and a moisture absorption expansion. The coefficient is 15 ppm or less, or the coefficient of thermal expansion is 1.
0 × 10 ^-5 ℃ ^-1 or more and 2.5 × 10 ^-5 ℃ ^-1 or less
It is to satisfy the above conditions.

The base film is represented by the general formula (1):

[0023]

Embedded image

The aromatic polyamic acid copolymer having a repeating unit represented by the formula (1) is obtained by dehydration and ring closure of an aromatic polyimide copolymer.

Further, the base film has the general formula (1)

[0026]

Embedded image

Wherein R ₁ is

[0028]

Embedded image

R ₂ is a divalent organic group selected from

[0030]

Embedded image

R ₃ is a divalent organic group selected from
0

[0032]

Embedded image

R ₄ is a tetravalent organic group selected from
_{3 -, Cl-, Br-, F-} , showing a CH ₃ O-. Further, m and n are integers and satisfy 1 ≦ m and 0 ≦ n. )
In which the aromatic polyamic acid copolymer represented by the formula (1) is obtained by dehydration and ring closure.

The gist of the FC tape according to the present invention is as follows. The base film has a water absorption of 1.6% or less, a moisture expansion coefficient of 15 ppm or less, and a thermal expansion coefficient of 1.
0 × 10 ^-5 ℃ ^-1 or more and 2.5 × 10 ^-5 ℃ ^-1 or less
It is to satisfy the above conditions.

The gist of the TAB tape according to the present invention resides in that the protective layer of the FC tape according to the fourth aspect of the present invention is peeled off and a copper foil is adhered to form a circuit.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION The base film used for the flexible printed circuit board, FC tape and TAB tape comprising the same used in the present invention is a film having excellent properties such as low thermal expansion, low water absorption, and low moisture expansion. Consists of Various materials can be considered as a film that satisfies the above-mentioned characteristics, and a polyimide film having the above-mentioned excellent characteristics is a polyimide film. As an example of the polyimide film, for example, the general formula (1)

[0037]

Embedded image

Wherein R ₁ is

[0039]

Embedded image

R ₂ is a divalent organic group selected from

[0041]

Embedded image

R ₃ is a divalent organic group represented by the following formula:

[0043]

Embedded image

A tetravalent organic group represented by R ₄ is CH
_{3 -, Cl-, Br-, F-} , showing a CH ₃ O-. m,
n is an integer and satisfies 1 ≦ m and 0 ≦ n. ), A polyimide film obtained by dehydration ring closure.

Flexible printed circuit board based on a polyimide film having the above characteristics as a base film, FC
The tape and the TAB tape composed of the tape have the advantage that there is no warp or curl and the dimensional change during processing and mounting is small.

Hereinafter, a method of manufacturing a flexible printed circuit board, an FC tape, and a TAB tape comprising the same according to the present invention will be described in detail.

A polyimide film having excellent properties such as low thermal expansion, low water absorption and low moisture expansion can be obtained by dehydrating and ring-closing a polyamic acid copolymer as a precursor. The polyamic acid copolymer solution is obtained by using an acid anhydride and a diamine component in substantially equimolar amounts and polymerizing in an organic polar solvent. As an example of this polyimide film, a method for producing the polyimide film having the above specific structure will be described. First, a method for producing a polyamic acid copolymer solution will be described.

In an atmosphere of an inert gas such as argon or nitrogen, a compound represented by the general formula (2) H ₂ N—R ₂ —NH ₂ (2) (wherein R ₂ represents a divalent organic group). One or two kinds of diamines are dissolved in an organic solvent or dispersed in a slurry. This solution was added to the general formula (3)

[0049]

Embedded image

(Wherein R ₁ represents a divalent organic group) and at least one aromatic diester dianhydride represented by the general formula (4):

[0051]

Embedded image

(Wherein R ₃ represents a tetravalent organic group), and a mixture of at least one kind of tetracarboxylic dianhydride in the form of a solid or an organic solvent is added to the polyamide. A solution of the acid copolymer is obtained.

The reaction temperature at this time is from -20 ° C to 100
° C, desirably 60 ° C or less. The reaction time is
It is about 30 minutes to 12 hours.

In this reaction, contrary to the above-mentioned addition procedure, first, a mixture of ester dianhydride and tetracarboxylic dianhydride is dissolved or diffused in an organic solvent, and the solid of the diamine is added to the solution. Alternatively, a solution or slurry using an organic solvent may be added. In addition, they may be mixed and reacted at the same time, and the mixing order of the acid anhydride component and the diamine component is not limited.

Examples of the organic solvent used for the reaction for producing the polyamic acid copolymer include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, and N, N-dimethylformamide and N, N-diethylformamide. Formamide solvents, N, N-dimethylacetamide, acetamido solvents such as N, N-diethylacetamide, N-methyl-2-pyrrolidone, pyrrolidone solvents such as N-vinyl-2-pyrrolidone, phenol, o-,
Examples thereof include phenol solvents such as m- or p-cresol, xylenol, halogenated phenol, and catechol, and hexamethylphosphoramide, γ-butyrolactone, and the like. These can be used with only one kind of solvent or a mixed solvent of two or more kinds. Further, it is also possible to use a mixture of aromatic hydrocarbons such as xylene and toluene.

Also, a mixed solvent comprising these polar solvents and a non-solvent of polyamic acid can be used. Examples of the non-solvent for the polyamic acid include acetone, methanol, ethanol, isopropanol, benzene, and methyl cellosolve. Further, a part of aromatic hydrocarbons such as xylene and toluene can be used.

Each of the polyamic acid copolymers is 5 to 40% by weight, preferably 10 to 30% by weight, in the above-mentioned organic polar solvent.
It is desirable from the viewpoint of handling that it is dissolved by weight%.

The polyamic acid copolymer produced preferably has a number average molecular weight of 10,000 to 1,000,000 in order to maintain the strength of the polyimide film. If the average molecular weight is less than 10,000, the resulting film becomes brittle, while if it exceeds 1,000,000, the viscosity of the polyamic acid varnish becomes too high and handling becomes unfavorable.

In such a reaction, the ratio of the acid anhydride component is determined by the molar ratio of the ester dianhydride represented by the general formula (3) to the tetracarboxylic dianhydride represented by the general formula (4). Is preferably used in the range of 10/90 to 100/0.

The diamine represented by the general formula (2) is preferably used in an equimolar amount to the total amount of the acid anhydride component.

More specifically, the diamine component used in the method for producing a polyamic acid copolymer is represented by the general formula (2) H ₂ N—R ₂ —NH ₂ (2) wherein R ₂ is

[0062]

Embedded image

And a divalent organic group represented by )).

As the acid anhydride used in the method for producing the polyamic acid copolymer, essentially various acid anhydrides can be used. More specifically, from the balance of various properties, a general acid anhydride can be used. Formula (3) 18

[0065]

Embedded image

(Wherein R ₁ is

[0067]

Embedded image

An aromatic diester dianhydride selected from the group consisting of a divalent organic group represented by the general formula (4):
Chemical formula 20

[0069]

Embedded image

Wherein R ₃ is

[0071]

Embedded image

And a tetravalent organic group represented by It is preferred to use a tetracarboxylic dianhydride selected from

The acid component monomer used in the present invention may be obtained by reacting trimellitic anhydride chloride with phenols in the presence of pyridine in a solvent such as benzene or toluene, or by adding trimellitic anhydride in a high boiling solvent. It can be obtained by a method such as a transesterification reaction between an acid and a diacetate.

As described above, the obtained general formula (1)
The number of repetitions m and n of the block unit in the polyamic acid copolymer represented by is an integer and satisfies 1 ≦ m and 0 ≦ n.

Next, in order to obtain a polyimide copolymer and a polyimide film from the polyamic acid copolymer solution, dehydration ring closure is performed by using either a thermal method or a chemical method using a dehydrating agent. (Imidization).

For example, in the method of chemically dehydrating and ring-closing, first, a dehydrating agent having a stoichiometric amount or more and a catalytic amount of a tertiary amine are added to the above-mentioned polyamic acid copolymer or a solution thereof, and a support plate is added. An organic film such as PET or PET, or a support such as a drum or an endless belt is cast or coated to form a film, and the organic solvent is evaporated to obtain a self-supporting polyamic acid film. The evaporation of the organic solvent is preferably performed at a temperature of 150 ° C. or less for about 5 to 90 minutes.

Next, this is peeled off from the support and the end is fixed. Then, it is imidized by gradually heating to about 100 ° C. to 500 ° C., and after cooling, it is removed to obtain a polyimide film.

In the method of thermally dehydrating and cyclizing, a polyamic acid copolymer solution is cast or coated on a support plate, an organic film such as PET, a support such as a drum or an endless belt to form a film, Treat in the same manner as in the case of chemical dehydration.

When the method of thermally imidizing and the method of chemically imidizing are compared, the elongation of the polyimide copolymer obtained by the chemical method is excellent,
In addition, there are advantages in that the mechanical properties of polyimide such as a large mechanical strength and a small coefficient of linear expansion are improved, and that the chemical method enables imidization in a short time. In addition, it is also possible to use both the method of thermally imidizing and the method of chemically imidizing together.

Further, imidization is performed while heating and drying,
A polyimide film made of a polyimide copolymer is obtained. The heating temperature is preferably in the range of 110 ° C to 550 ° C. There is no particular limitation on the rate of temperature rise during heating, but it is preferable that the temperature is gradually increased so that the maximum temperature becomes the above-mentioned temperature. The heating time varies depending on the film thickness and the maximum temperature.
A range from 0 seconds to 10 minutes is preferred. When heating and drying / imidizing a film having self-supporting properties, the film having self-supporting properties is peeled off from the support, and the end portion is fixed and heated in that state to reduce the linear thermal expansion coefficient. A polyimide film is obtained.

Examples of the dehydrating agent include aliphatic dianhydrides such as acetic anhydride and aromatic dianhydrides. Examples of the catalyst include aliphatic amines such as triethylamine, aromatic amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine, picoline and isoquinoline.

It is well known that polyimide is equivalent to polyisoimide, but it is also possible to improve the solvent solubility by selecting an isoimide structure.
In order to obtain a polyisoimide copolymer, the above chemical ring-closing agent is replaced with a diimide such as dicyclohexylcarbodiimide (DCC) and / or a carboxylic acid such as trifluoroacetic acid, and a reaction similar to the formation of the polyimide copolymer is performed. Should be performed.

In the production of this polyimide film, a thermoplastic resin such as nylon, polyvinyl acetate, polytetrafluoroethylene, or polymethyl methacrylate is added to a solution of a polyamic acid copolymer which is a precursor of the polyimide copolymer. Films may be obtained by blending organic additives such as resins, or inorganic fillers such as glass fibers, or various reinforcing agents. By blending these, various properties such as mechanical strength and adhesiveness can be obtained. It is possible to further improve.

The polyimide film having a specific structure obtained by the above method has a coefficient of hygroscopic expansion of not more than 15 ppm and a coefficient of thermal expansion of not less than 1.0 × 10 ^-5 ° C. ^{-1 and not} more than 2.5 × 1.
0 ^-5 ° C ^-1 or less, and the water absorption is 1.6% or less.
It is suitable as a base film for a tape and a TAB tape made of the tape, and has the advantage that there is no warping or curling, and the dimensional change during processing and mounting is small.

The base film of the flexible printed circuit board, FC tape and TAB tape comprising the same according to the present invention has a coefficient of hygroscopic expansion of 15 ppm or less.
Thermal expansion coefficient, 1.0 × 10 ^-5 ℃ ^-1 or 2.5 × 10 ^-5
C- ¹ or less, and the water absorption is 1.6% or less.
Any structure can be preferably used as long as the film has the above, and the film used as the base film of the present invention is not limited to the specific structure described above.

The film obtained by the above method is used as a base film for the flexible printed circuit board, FC tape and TAB tape comprising the same according to the present invention. In this case, the thickness is about 25 μm to 180 μm. However, the thickness is about 50 μm to 180 μm in consideration of the convenience of handling, the film strength, and the demand for thinner layers for miniaturization.
125 μm is more preferred.

Next, a method of manufacturing a flexible printed circuit board according to the present invention will be described. The flexible printed board according to the present invention is prepared by applying an adhesive having a predetermined composition to a final film thickness of 10 to 100 μm, preferably 15 to 30 μm.
m is uniformly applied to a base film as an insulating material. The adhesive solution is dried to bring the adhesive layer into a semi-cured state (B-staged state). A copper foil is overlaid on the adhesive layer, and 0.1 kg / cm ² at 20 ° C. to 180 ° C.
Pressure bonding is performed under the above conditions, and the adhesive is cured at a temperature at which the adhesive is cured. A resist is applied, a circuit is drawn on the resist by exposure or the like, development is performed, copper is etched, and the resist is peeled off. Through the above manufacturing process, an FPC is created.

The flexible printed circuit board according to the present invention is characterized in that the base film has low moisture expansion and low thermal expansion as its properties. Therefore, since the dimensional change due to moisture absorption and dehumidification in each processing step is small, circuit formation and IC mounting are performed. Later, electricity
There is no displacement when mounting on electronic components,
Has excellent dimensional stability.

Next, a method for producing an FC tape according to the present invention will be described. About 1 adhesive on a protective layer such as PET
It is applied to a thickness of 0 to 30 μm, dried at a temperature of about 80 ° C. to 150 ° C. for about 0.5 to 20 minutes, and a cover film is laminated to form a three-layer structure of PET / adhesive / cover film. The three-layer film is slit into a predetermined width.

Separately, the base film produced by the above method is slit into a predetermined width. The cover film of the three-layer film is peeled off, and the organic insulating film is slit at a temperature of about 50 ° C. to 150 ° C. so that the adhesive is fused to the film (organic insulating film) separately manufactured by the above method. Are laminated, and the F according to the present invention, which has a three-layer structure of a protective layer / adhesive / organic insulating film, is used.
C tape is obtained.

Next, a method for manufacturing a TAB tape according to the present invention will be described. That is, the TAB tape is formed by forming a sprocket hole and a device hole by punching the FC tape manufactured by the above manufacturing method, peeling and removing the protective layer, then curing the copper foil laminate, the adhesive, and forming an arrangement pattern (resist). The TAB tape according to the present invention is obtained by performing coating, etching of copper, and resist stripping) and plating.

More specifically, the bonding method is as follows. An adhesive having a predetermined composition is coated on a protective film in a final film thickness of 10 to 40.
μm, preferably 15 to 30 μm. The adhesive solution is dried to bring the adhesive layer into a semi-cured state (B-staged state). The FC tape obtained by the above manufacturing method is superimposed on the adhesive layer, and 2
Crimping is performed at 0 ° C. to 180 ° C. under a condition of 0.1 kg / cm ² or more. According to the manufacturing method as described above, the TA according to the present invention
B tape is obtained.

The protective film serving as the protective layer of the adhesive layer may be basically any material as long as it has a heat resistance that does not cause softening or deterioration when the adhesive is dried. A polyester film such as polyethylene terephthalate or a polyolefin film such as polypropylene is suitable.

The TAB tape obtained as described above has a coefficient of hygroscopic expansion of not more than 15 ppm and a coefficient of thermal expansion of not less than 1.0 × 10 ^-5 ° C ^{-1 and not} more than 2.5 × 10 ^-5 ° C ^-1. In addition, by using a polyimide film having an excellent property that the water absorption is 1.6% or less, the displacement of the joining position between the base film and the LSI in the inner lead bonding process can be reduced. In addition, there is an advantage that there is no displacement of the joining position between the outer lead and the substrate in the outer lead bonding processing step, and no curling occurs in the copper foil laminating processing step.

Further, since the TAB tape according to the present invention has a low hygroscopic expansion and a low thermal expansion, the dimensional change in each processing step is small, so that a TAB tape having a finer line pattern can be provided. In addition, since the organic insulating film has a high elastic modulus, the thickness of the organic insulating film can be reduced, and a thin IC package can be manufactured.
Furthermore, since the dimensional change in each processing step is small, the electrical reliability at each joint surface is high, and the computer IC
It can also be used for mounting.

The adhesive used for the flexible printed circuit board, the FC tape and the TAB tape made of the same according to the present invention may be a conventionally known material. Specifically, for example, epoxy resin, polyamide resin , Phenolic resin, acrylic resin, polyimide resin,
A rubber-based resin or the like may be used alone or mixed with a solvent at various ratios, and if necessary, an additive such as a curing agent or a curing accelerator may be used.

As described above, the flexible printed circuit board, the FC tape, and the TAB tape made of the same have been described as examples of the embodiments in order to clarify their usefulness, but the present invention is not limited thereto. Instead, the present invention can be implemented in various modified, changed, and modified aspects based on the knowledge of those skilled in the art without departing from the spirit thereof.

[0098]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a flexible printed board, an FC tape and a TAB comprising the same according to the present invention will be described by way of examples.
The tape will be described. First, the flexible printed circuit board, FC tape and TAB comprising the same according to the present invention
A production example of an acid component used for producing a polyimide copolymer constituting a polyimide film used as a base film of a tape will be described.

(Production Example 1) Synthesis of acid component: P-phenylenebis (trimellitic acid monoester anhydride) 510 g of trimellitic anhydride chloride (2 g) in a 3000 ml three-necked flask equipped with a dropping funnel and a reflux condenser. .4
Mol) and 1000 ml of toluene and stirred at about 80 ° C. 132 g (1.2 mol) of hydroquinone was dissolved in 1200 ml of toluene and 240 ml of pyridine,
It is dripped from the dropping funnel into the neck flask. After the dropwise addition, the mixture was stirred under reflux for about 2 hours. After cooling, the precipitate was separated by filtration to obtain a white solid. The white solid is washed with 3 liters of water, dried, stirred under reflux with acetic anhydride for about 2 hours, and filtered. The white solid obtained by filtration was recrystallized from DMF,
g of a white solid were obtained.

(Production Example 2) Acid component: Synthesis of p-methylphenylenebis (trimellitic acid monoester acid anhydride) Instead of hydroquinone, methylhydroquinone 14
Except that 7.6 g (1.2 mol) was used, 350 g of a white solid was obtained in the same manner as in Production Example 1.

(Production Example 3) Synthesis of acid component: p- (2,3 dimethylphenylene) bis (trimellitic acid monoester anhydride) Instead of hydroquinone, 165.6 g of 2,3-dimethylhydroquinone (1. Except for using 2 mol), 400 g of a white solid was obtained in the same manner as in Production Example 1.

[0102] (Production Example 4) acid component: 4,4 ^'- instead of synthetic hydroquinone biphenylene bis (trimellitic acid monoester acid anhydride), ^4,4' - dihydroxybiphenyl 223.2 g (1.2 mol ) Was obtained in the same manner as in Production Example 1 except that) was used to obtain 400 g of a white solid.

(Production Example 5) Synthesis of acid component: 1,4-naphthalenebis (trimellitic acid monoester anhydride) In place of hydroquinone, 192.0 g (1.2 mol) of 1,4-dihydroxynaphthalene was used. Except for using it, 380 g of a white solid was obtained in the same manner as in Production Example 1.

(Production Example 6) Acid component: Synthesis of 2,6-naphthalenebis (trimellitic acid monoester anhydride) In place of hydroquinone, 192.0 g (1.2 mol) of 2,6-dihydroxynaphthalene was used. Except for using it, 385 g of a white solid was obtained in the same manner as in Production Example 1.

Next, the present invention will be described specifically with reference to examples, but the present invention is not limited to the scope of these examples. In the examples, ODA is 4,4'-diaminodiphenyl ether, and BAPP is 2,2'-bis [4-
(4-aminophenoxy) phenyl] propane, BAPB
4,4 ^'- bis (4-aminophenoxy) biphenyl,
TPE-Q is 1,4-bis (4-aminophenoxy)
Benzene and p-PDA are paraphenylenediamine, N
MP represents N-methylpyrrolidone, PMDA represents pyromellitic anhydride, and DMF represents dimethylformamide.

(Example 1) NM was placed in a separable flask.
Two equivalents of P and p-PDA and one equivalent of ODA were taken and stirred well at room temperature until the diamine compound was completely dissolved. Next, 2.85 equivalents of p-phenylenebis (trimellitic acid monoester anhydride) shown in Production Example 1 was gradually added as a powder, and then stirred for 40 minutes. Then, p-phenylenebis (trimellitic acid monoester anhydride) is added.
15 equivalents were dissolved in NMP, gradually added, and then cooled and stirred for 1 hour to obtain an NMP solution of a polyamic acid copolymer. The amount of NMP used is such that the concentration of charged monomers of diamines and aromatic tetracarboxylic dianhydrides is 18%.
% By weight.

Next, the polyamic acid copolymer solution was mixed with acetic anhydride and β-picoline, and cast and coated on a glass plate.
After drying at about 100 ° C. for about 5 minutes, the polyamic acid coating film is peeled off from the glass plate, and the coating film is fixed to a support frame. Thereafter, the coating film is applied at about 100 ° C. for about 5 minutes, at about 200 ° C. for about 5 minutes, about 300 minutes.
C. for about 5 minutes, heated at about 400.degree. C. for about 5 minutes, dehydrated and ring-closed to obtain a polyimide film of about 50 .mu.m. Table 1 shows the physical properties of the obtained polyimide film.

The coefficient of thermal expansion was measured at 100 ° C. to 200 ° C. by a TMA 8140 manufactured by Rigaku Corporation under a nitrogen stream.
Refers to the coefficient of thermal expansion in ° C. The water absorption is 150
The weight but was dried for 30 minutes at ℃ City W _1, 24
After immersion in distilled water for a long time and wiping off water droplets on the surface, the weight is defined as W ₂ and calculated by the following equation. Water absorption (%) = (W ₂ −W ₁ ) ÷ W ₁ × 100

The modulus of elasticity is according to ASTM D882.

[0110]

[Table 1]

A protective polyethylene terephthalate (hereinafter, referred to as PET) film having a surface treated with a release agent was coated with 50 parts of a bisphenol A type epoxy resin (E1001 / Yukahka Shell Epoxy) and a cresol novolak type epoxy resin (180H65 / Yuka Shell Epoxy Co., Ltd.) 10 parts, polyamide resin (M1276 / Nihon Rilsan Co., Ltd.) 40 parts, diaminodiphenyl sulfone 7 parts,
After drying an adhesive consisting of 2 parts of dicyandiamide, 35 parts of toluene and 15 parts of isopropyl alcohol, about 20 μm after drying
And dried at 150 ° C. for 10 minutes. This PET film with adhesive is slit to a width of 26 mm,
The polyimide film slit to a width of 35 mm was pressure-bonded at about 100 ° C. to obtain an FC tape.

After the PET film of the FC tape was removed, the adhesive surface and the copper foil (Low-prof, manufactured by Mitsui Kinzoku) were used.
ile electrolytic copper foil VLP-3EC) was laminated at 120 ° C., and after observing the appearance in this state, the dimensional change after etching was measured in accordance with the above method. Table 1 shows the results.

The dimensional stability was evaluated by obtaining the dimensional change rate by the following method. That is,
Except for the PET film, the FC tape composed of the base polyimide film, the adhesive, and the protective PET film is replaced with a copper foil (Low-profile electrolytic copper foil VLP made by Mitsui Kinzoku).
-3EC), and after heating and curing,
Insert two marking holes a and b for dimensional change rate measurement into MD
(Machine direction of production) opened by punching in a direction to measure the initial value l ₁ between a-b in this case. Next, the entire surface of the copper foil was etched to measure l ₂ between a and b. The following formula, Equation 1

(Equation 1) , The dimensional change before and after the etching was calculated. Example 2 A polyamic acid copolymer was obtained in the same manner as in Example 1 except that 1 equivalent of BAPP was used instead of ODA, and a polyimide film of about 50 μm was obtained in the same manner as in Example 1. . Table 1 shows the physical properties of the obtained polyimide film.

(Example 3) Instead of ODA, BAPB
A polyamic acid copolymer was obtained in the same manner as in Example 1 except that 1 equivalent was used.
Was obtained. Table 1 shows the physical properties of the obtained polyimide film.

Example 4 Instead of ODA, TPE-
A polyamic acid copolymer was obtained in the same manner as in Example 1 except that Q1 equivalent was used.
m was obtained. Table 1 shows the physical properties of the obtained polyimide film.

Example 5 Production Example 2 was repeated in place of p-phenylenebis (trimellitic acid monoester anhydride).
A polyamic acid copolymer was obtained in the same manner as in Example 1 except that 3 equivalents of p-methylphenylenebis (trimellitic acid monoester dianhydride) shown in A polyimide film of about 50 μm was obtained. Table 1 shows the physical properties of the obtained polyimide film.

Example 6 Production Example 3 was repeated in place of p-phenylenebis (trimellitic acid monoester anhydride).
A polyamic acid copolymer was obtained in the same manner as in Example 1 except that 3 equivalents of p- (2,3 dimethylphenylene) bis (trimellitic acid monoester anhydride) were used. A polyimide film of about 50 μm was obtained in the same manner. Table 1 shows the physical properties of the obtained polyimide film.

Example 7 Production Example 4 was used instead of P-phenylenebis (trimellitic acid monoester anhydride).
Indicated by 4,4 ^'- biphenylene bis (trimellitic acid monoester acid anhydride) was used 1 equivalent of the obtained polyamic acid copolymer in the same manner as in Example 1, as in Example 1 By the method, a polyimide film of about 50 μm was obtained.
Table 1 shows the physical properties of the obtained polyimide film.

(Example 8) Instead of ODA, BAPP
A polyamic acid copolymer was obtained in the same manner as in Example 7, except that 1 equivalent was used.
Was obtained. Table 1 shows the physical properties of the obtained polyimide film.

(Embodiment 9) Instead of ODA, BAPB
A polyamic acid copolymer was obtained in the same manner as in Example 7, except that 1 equivalent was used.
Was obtained. Table 1 shows the physical properties of the obtained polyimide film.

Example 10 Instead of ODA, TPE
A polyamic acid copolymer was obtained in the same manner as in Example 7 except that -Q1 equivalent was used.
A μm polyimide film was obtained. Table 1 shows the physical properties of the obtained polyimide film.

(Example 11) Instead of p-phenylenebis (trimellitic acid monoester acid anhydride), 1,4-naphthalenebis (trimellitic acid monoester acid dianhydride) 3 shown in Production Example 5 was used. A polyamic acid copolymer was obtained in the same manner as in Example 1 except that an equivalent amount was used, and a polyimide film of about 50 μm was obtained in the same manner as in Example 1. Table 1 shows the physical properties of the obtained polyimide film.

Example 12 Instead of p-phenylenebis (trimellitic acid monoester acid anhydride), 2,6-naphthalenebis (trimellitic acid monoester acid anhydride) shown in Production Example 6 was used. Other than the above, a polyamic acid copolymer was obtained in the same manner as in Example 1, and a polyimide film of about 50 μm was obtained in the same manner as in Example 1. Table 1 shows the physical properties of the obtained polyimide film.

Example 13 A separable flask was charged with N
Two equivalents of MP and p-PDA and one equivalent of ODA were taken and stirred well at room temperature until the diamine compound was completely dissolved.
Next, 2 equivalents of p-phenylenebis (trimellitic acid monoester anhydride) shown in Production Example 1 were gradually added in powder form, and the mixture was stirred for 40 minutes. 0.85 equivalents of oxydiphthalic anhydride is gradually added as a powder,
Minutes. Then, 0.15 equivalents of oxydiphthalic anhydride was dissolved in NMP, gradually added, and then cooled and stirred for 1 hour to obtain an NMP solution of a polyamic acid copolymer. In addition, the amount of NMP used is such that the concentration of charged monomers of diamines and aromatic tetracarboxylic dianhydrides is
It was adjusted to 18% by weight. Using the obtained polyamic acid copolymer solution, the same method as in Example 1 was used to obtain about 50 μm
Was obtained. Table 1 shows the physical properties of the obtained polyimide film.

(Example 14) Example 13 was repeated except that benzophenonetetracarboxylic anhydride (BTDA) was used instead of oxydiphthalic anhydride.
A polyamic acid copolymer was obtained in the same manner as in Example 1, and a polyimide film having a thickness of about 50 μm was obtained in the same manner as in Example 1.
Table 1 shows the physical properties of the obtained polyimide film.

Example 15 A polyamic acid copolymer was obtained in the same manner as in Example 13 except that biphenyltetracarboxylic anhydride (BPDA) was used instead of oxydiphthalic anhydride. A polyimide film of about 50 μm was obtained in the same manner as described above. Table 1 shows the physical properties of the obtained polyimide film.

Example 16 Instead of oxydiphthalic anhydride, pyromellitic anhydride (PMDA)
A polyamic acid copolymer was obtained in the same manner as in Example 13 except for using, and a polyimide film of about 50 μm was obtained in the same manner as in Example 1. Table 1 shows the physical properties of the obtained polyimide film.

(Comparative Example 1) In the same manner as in Example 1 described above, 50 μm
Was obtained. Table 1 shows the physical properties of the obtained polyimide film. Using this polyimide film, an FC tape was obtained and laminated with a copper foil in the same manner as in Example 1 to observe the appearance and measure the dimensional change. The results are shown in Table 1.

Comparative Example 2 One equivalent of DMF and ODA was placed in a 2-liter separable flask, mixed well at room temperature until the diamino compound was completely dissolved, and then stirred while cooling with ice. Next, 2 equivalents of PMDA were added and 40
And stirred for 30 minutes. Then, 1 equivalent of p-PDA was dissolved in DMF, gradually added, and then cooled and stirred for 1 hour to obtain a polyamic acid copolymer DMF solution. It was fired in the same manner as in Example 1 to obtain a 50 μm polyimide film. Table 1 shows the physical properties of the obtained polyimide film.

Using this polyimide film, in the same manner as in Example 1, an FC tape was obtained, laminated with a copper foil, and the appearance was observed and the dimensional change was measured. Table 1 shows the results
It was shown to.

[0131]

As described above, as shown in the specific embodiments,
The flexible printed circuit board, the FC tape and the TAB tape comprising the same according to the present invention have a characteristic that the linear expansion coefficient is not extremely different from that of metal or glass, and has a specific high elastic modulus and a low water absorption. . Specifically, a polyimide film obtained by mixing a polyamic acid copolymer represented by the general formula (1) and a chemical dehydrating agent is used as a base film.
The present invention provides a tape and a TAB tape made of the tape, and has no warp or curl, and has a small dimensional change during processing and mounting, so that it is a material suitable for a tape carrier package having a multi-pin high-density pattern.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 27/34 B32B 27/34 C08G 73/16 NTK C08G 73/16 NTK // C08J 5/18 CFG C08J 5/18 CFG

Claims (5)

[Claims] 1. A flexible printed circuit board comprising at least a conductive layer and a base film laminated on each other, wherein the base film has a water absorption of 1.6% or less, a moisture expansion coefficient of 15 ppm or less, or a thermal expansion coefficient of 1. 0x10
^-5 ° C. ^-1 or 2.5 × 10 ^-5 ℃ ^-1 of the following, a flexible printed circuit board, wherein the one or more conditions are satisfied. 2. The base film according to claim 1, wherein the base film has the general formula (1). The flexible printed circuit board according to claim 1, comprising an aromatic polyimide copolymer obtained by dehydrating and ring-closing an aromatic polyamic acid copolymer having a repeating unit represented by the following formula: 3. The method according to claim 1, wherein the base film has the general formula (1). (Wherein R ₁ is R ₂ is a divalent organic group selected from R ₃ is a divalent organic group selected from A tetravalent organic group selected from R ₄ is CH ₃ —, Cl
—, Br—, F—, and CH ₃ O—. Further, m and n are integers and satisfy 1 ≦ m and 0 ≦ n. 3. The flexible printed circuit board according to claim 1, comprising an aromatic polyimide copolymer obtained by dehydrating and ring-closing the aromatic polyamic acid copolymer represented by the formula (1). 4. The base film has a water absorption of 1.6% or less, a moisture absorption expansion coefficient of 15 ppm or less, and a thermal expansion coefficient of 1.
0 × 10 ^-5 ℃ ^-1 or more and 2.5 × 10 ^-5 ℃ ^-1 or less
An FC tape satisfying the above conditions. 5. A TAB tape, wherein a circuit is formed by peeling a protective layer of the FC tape according to claim 4 and pasting a copper foil.