KR20060052481A - Copper-clad laminate for cof and carrier tape for cof - Google Patents

Abstract

Provided is a copper clad laminate for COF, which can form a circuit of a fine pattern and can prevent intrusion into a polyimide layer of a conductor during an Au-Sn process.

A copper-clad laminate having a polyimide layer provided on a copper foil, the polyimide layer having a thickness of 5 to 20 µm, obtained by coating, drying and curing in a solution state on the copper foil, exhibiting non-thermoplastic properties at 350 ° C. The thickness is 5-50 μm, the surface roughness is in the range of 0.5-1.5 μm, and the metal-treated layer, chromate-treated layer and silane coupling agent-treated layer treated with at least one metal selected from Mo, Co, Ni or Zn A copper clad laminate for COF having a 180 ° peel strength of 0.6 kN / m or more at room temperature between copper-polyimide and a carrier tape for COF obtained by processing the same.

Description

Copper-clad Laminate for COF and Carrier Tape for COF}

1 is a conceptual diagram showing an example in which an IC chip is mounted on a film carrier tape for COF.

**** Description of the symbols for the main parts of the drawings ***

1: IC chip (1), 2: bump,

3: polyimide layer, 4: circuit

The present invention relates to a copper clad laminate for COF (Chip on Film) and a carrier tape for COF obtained by processing the same.

COF is a composite component in which a semiconductor IC is mounted on a film-shaped wiring board. In many cases, COF is used in connection with larger rigid wiring boards or display boards. And a film-shaped wiring board is produced from the copper clad laminated board which laminated | stacked organic polymer films, such as polyimide, and copper foil.

The film-shaped wiring board laminates a photosensitive resin layer on the copper foil surface of a copper clad laminated board, performs exposure corresponding to a desired wiring pattern, photocures the photosensitive resin of a required part, and develops the photosensitive resin of an unexposed part. After the removal, the coated copper layer of the substrate which is not covered with the cured resist is removed by etching, or the plating metal is deposited in the part not covered with the cured resist by plating. Finally, the method of removing the hardening resist by peeling and obtaining the wiring board which has a desired conductor pattern is employ | adopted. As a method of laminating | stacking photosensitive resin, there exists a method of apply | coating and drying a liquid resist, and the method of laminating | stacking a photosensitive resin film.

As a copper clad laminated board for COF, the polyimide copper clad laminated board obtained by sputtering copper to a polyimide resin film mainly has been used. In the case of the sputtering method, since the yield is easily deteriorated by the pinhole of the metal layer, a polyimide copper clad laminate without a pinhole is preferable. As a copper clad laminated board without a pinhole, the rolled copper foil, the electrolytic copper foil, and the polyimide were laminated | stacked. Although this laminated board is obtained by laminating | stacking a polyimide on copper foil by a casting or lamination method, in order to improve red crushing force etc., a thermoplastic polyimide layer may be formed on metal foil.

On the other hand, chip mounting is carried out at a low temperature such as ACF, NCP, ultrasonic bonding, or at a high temperature of 300 ° C. such as Au-Au bonding or Au-Sn bonding. In view of the rapid connection between chips and wirings, many Au-Au junctions and Au-Sn junctions are employed.

Japanese Patent Application Laid-Open No. 2004-207670 discloses an example in which a release agent layer such as a silane compound or silica sol is provided on a side surface on the side opposite to the side where the semiconductor chip of the insulating layer is mounted as a flexible printed wiring board for COF. Japanese Laid-Open Patent Publication No. 2004-153194 discloses a method of manufacturing a COF wiring board, including a step of forming a release agent layer on an insulating layer after a photolithography step of patterning. The insulating layer is formed of a thermoplastic resin layer obtained by coating or thermocompressing a polyimide precursor resin solution on a conductor layer and an insulating film, and the thermosetting resin layer and insulating film of which the insulating layer is thermocompressed. It also describes what is formed.

Japanese Patent Application Laid-Open No. 2004-128337 discloses a method for producing COF, a resin coating step of applying an insulating resin to the surface of an insulating tape, and a semiconductor element pressing process for pressing a semiconductor element from an insulating resin onto a wiring pattern to pressurize it on a wiring pattern. And a resin curing step of curing an insulating resin and fixing the semiconductor element in a state in which the semiconductor element is electrically connected by pressure welding on a wiring pattern. Japanese Patent Application Laid-Open No. 2004-31685 discloses a method for producing a COF film carrier tape, which is a step of adhering a reinforcing film on the side opposite to the conductive layer of the insulating layer and thermally compressing the sprocket hole in the areas on both sides in the width direction. And a step of again performing thermocompression bonding of the reinforcing film and the insulating layer, and forming a wiring pattern by forming and etching a resist pattern on the conductive layer and simultaneously forming dummy wiring around the plurality of sprocket holes. This is described.

Japanese Patent Application Laid-Open No. 2001-315256 discloses a flexible metal foil copper clad laminate used for HDD, COF, etc., comprising a metal foil, a thermoplastic polyimide layer and a heat resistant base film, and having a thermoplastic polyimide layer having a glass of 150 to 300 ° C or less. It is described that a thermoplastic polyimide having a transition temperature and a water absorption of 1% or less, and a heat resistant base film using a thermoplastic polyimide film having a glass transition temperature of 350 ° C. or higher and a water absorption of 2% or less at the same time, respectively. Japanese Laid-Open Patent Publication No. 2003-71984 discloses a polyimide copper clad laminate in which a thermoplastic polyimide layer is formed on at least one surface of a non-thermoplastic polyimide layer, and copper foil is laminated on the surface of the thermoplastic polyimide layer, which is bonded to a thermoplastic polyimide. The polyimide copper clad laminated board whose thickness of copper foil is 5 micrometers or less is described, and it describes that this is used for COF etc. Japanese Patent Laid-Open No. 2003-23046 discloses a copper clad laminate for COF having the characteristics of copper foil.

In general, in the case of the polyimide laminate obtained by the sputtering method, since the thermoplastic resin layer is not necessary, the phenomenon that the metal wiring penetrates into the polyimide layer at the time of chip mounting of 300 ° C. or higher does not occur, but there are problems as described above. . When laminating | stacking a polyimide layer to copper foil by application | coating, crimping | bonding, etc., in order to raise the adhesive force between copper foil and a polyimide layer, it is generally necessary to use thermoplastic polyimide, and there exists a problem, such as a phenomenon which invades. In particular, in the case of the flexible chip mounting using the Au-Sn process in the COF manufacturing process, there is a problem of causing heat deformation because of being exposed to high temperature and high pressure, and the conductor penetrates into the polyimide layer. And when a laminated board is manufactured by using a coating method (called the casting method) for a polyimide resin or its precursor solution, a copper foil is roughened, an anchor effect is exhibited, and thermoplastic polyimide is used. Instead, a method of increasing the adhesive strength has been proposed. However, this method requires the circuit formation of the fine pattern of the material for COF, but has a problem of inhibiting it.

An object of the present invention is to provide a copper clad laminate for COF which can form a circuit of a fine pattern and can prevent invasion of the conductor into the polyimide layer during the Au-Sn process.

This invention is a copper clad laminated board provided with a polyimide layer on copper foil, The polyimide layer was obtained by apply | coating, drying, and hardening | curing in solution state on copper foil, and exhibits non-thermoplastic characteristics at 350 degreeC, and the polyimide laminated surface of copper foil The surface roughness (Rz) is in the range of 0.5 to 1.5 µm, and the 180 ° peeling strength at room temperature between copper and polyimide is 0.6 kN / m or more. Moreover, this invention is a carrier tape for COF obtained by processing the said copper clad laminated board for COF.

Here, the polyimide layer being a single layer facilitates the production of the copper clad laminate for COF. In addition, the copper foil is an unharmonized electrolytic copper foil, and the metal-treated layer treated with at least one metal selected from the group consisting of molybdenum, cobalt, nickel and zinc on the polyimide laminated side of the copper foil, and chromate treatment. Having a layer and a silane coupling treatment layer is advantageous because it increases the adhesive strength between the polyimide layer and the copper foil. Thus, the metal treatment layer is an alloy layer composed of zinc and nickel to impart higher adhesive strength. Moreover, if the thickness of copper foil exists in the range of 5-20 micrometers, and the thickness of a polyimide layer exists in the range of 5-50 micrometers, usability as a carrier tape for COF will improve.

The present invention is further described below.

The copper clad laminated board for COF consists of a copper foil and a polyimide layer, and copper foil may be in one surface side, and may be in both surfaces.

The polyimide layer may consist of a single layer or a plurality of layers, but the single layer is easy to manufacture. When it consists of multiple layers, the structure which has a thin polyimide layer for improving the adhesive strength with copper foil on the adhesion surface side, and has a thick polyimide layer on the surface side which shows high rigidity at high temperature is preferable. The thickness ratio in this case is preferably in the range of 1: 2 to 1: 100. The polyimide layer exhibits non-thermoplastic properties at 350 ° C, preferably 400 ° C. In addition, when a polyimide layer consists of multiple layers, any polyimide layer also shows the said characteristic. Here, the non-thermoplastic characteristic means that storage elastic modulus shows 0.5 GPa or more. If the storage modulus is too high, the adhesiveness tends to be lowered, and therefore it is preferable to exhibit 3.0 GPa or less under the above conditions. Hereinafter, the polyimide (layer) which shows the non-thermoplastic characteristic used by this invention is also called non-thermoplastic polyimide (layer) or simply polyimide (layer).

The copper clad laminated board for COF of this invention is manufactured by apply | coating the solution of the polyimide or the precursor of polyimide on copper foil, drying, and hardening to form a polyimide layer. The laminated board which has copper foil on both surfaces is manufactured by thermocompression bonding copper foil (you may have a polyimide layer) on the surface of the said polyimide layer.

The non-thermoplastic polyimide forming the non-thermoplastic polyimide layer is not particularly limited, but a polyimide synthesized from a specific diamine and a specific tetracarboxylic dianhydride can be preferably used. As such diamine, o-phenylenediamine, p-phenylenediamine, m-phenylenediamine, 4,4'- diaminophenyl ether, 3,4'- diamino diphenyl ether, 3,3'- diamino Diphenylether, 4,4'-diamino-biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl) propane And 4,4'-diamino-benzanilide which may have substituents, such as an alkyl group and an alkoxy group, are mentioned. These may be used individually or 2 types or more. Moreover, although it can also use together with other diamine, it is preferable that the usage-amount of the said diamine component is 70 mol% or more.

As said specific tetracarboxylic dianhydride, a pyromellitic dianhydride, 3,3 ', 4,4'-biphenyl tetracarboxylic dianhydride, 2,2', 3,3'-biphenyl tetracarboxylic Acids and the like can be enumerated. These may use individual or 2 types or more. Moreover, although it can also use together with other tetracarboxylic dianhydride, it is preferable that the usage-amount of the said specific tetracarboxylic dianhydride is 70 mol% or more.

Moreover, as a non-thermoplastic polyimide which forms a non-thermoplastic polyimide layer, the polyimide solution or its precursor solution which is an intermediate of a commercially available non-thermoplastic polyimide film can be used. For example, Upyrex® S, SGA, SN, Kafton® H, V, EN of Toray-Dupont Co., Ltd, Apical® AH of Kaneka Corporation, Intermediates such as NPI, HP and the like.

Although the thickness of a polyimide layer does not restrict | limit especially, 2-100 micrometers, Preferably 5-50 micrometers is suitable.

The copper foil used by this invention consists of copper or the copper alloy containing 90% or more of copper, Although the thickness does not have a restriction | limiting in particular, 3-30 micrometers, Preferably 5-20 micrometers is suitable. The copper foil may be an electrolytic copper foil or a rolled copper foil, but an electrolytic copper foil is preferably used. And it is suitable that this copper foil is not roughening process.

Since the surface (called the surface which contact | connects a polyimide layer) of copper foil improves adhesiveness with a polyimide layer, it is preferable to surface-treat. In this surface treatment, it is preferable to provide a metal treatment layer, a chromate treatment layer, and a silane coupling treatment layer in order on the surface of copper foil.

In the method of providing the metal treatment layer, at least one metal selected from Mo, Co, Ni and Zn is attached to the surface of the copper foil, preferably a metal containing both Zn and Ni. This adhesion amount is 1-50 microgram / cm <^2> as a metal, Preferably it is about 5-50 microgram / cm <^2> . When both Zn and Ni are essential, it is preferable to set Zn to 1 to 5 µg / cm ² , Ni to 1 to 15 µg / cm ² , and to set the Ni / (Ni + Zn) ratio to 0.70 or more. As a method of attaching a metal, a known method such as an electric or chemical plating method, a vacuum or a chemical vapor deposition method can be used.

As a method of providing a chromate treatment layer, well-known methods, such as a cathode process which dipped the copper foil which installed the metal treatment layer in the sodium dichromate solution, and supplies an electric current, can be used. The method of providing a silane coupling agent treatment layer is a well-known method of applying a silane coupling agent-containing solution such as 3-glycidoxypropyltrimethoxysilane to the copper foil provided with the chromate treatment layer by a spray method or the like, and drying the same. Can be used.

Roughness Rz is the range of 0.5-1.5 micrometers of the copper foil surface (when surface-treated, the surface after surface treatment is used) used by this invention. If the surface roughness Rz is smaller than this range, there is a problem that good contact strength cannot be obtained. If the surface roughness Rz is large, problems such as difficulty in forming a fine wiring are likely to occur.

The copper foil laminated plate for COF of this invention can be manufactured by the method of apply | coating the solution of a non-thermoplastic polyimide or precursor (henceforth varnish) to copper foil surface, and drying and hardening. As a method for applying the varnish, a known method such as a die coater, comma coater, roll coater, gravure coater, curtain coater, spray coater and the like may be adopted. In this case, it can apply | coat in multiple layers as needed. As a method for drying and curing the applied varnish, a conventional heat drying furnace can be used. As an atmosphere of a drying furnace, air, an inert gas (nitrogen, argon), etc. can be used. As temperature of drying and hardening, the temperature range of about 60-400 degreeC is used preferably. Hardening is performed until a polyimide precursor turns into a polyimide. In addition, when it is necessary to make copper foil thickness thin, a part of copper foil is removed to constant thickness by an etching process etc., and copper foil thickness is made into predetermined thickness.

The copper foil laminated sheet for COF of this invention obtained in this way needs to be 0.6 kN / m or more as normal temperature and 180 degree peeling strength between copper- polyimide layers. Preferred peel strength ranges from 0.8 to 2.0 kN / m. Such peeling strength can be obtained by selecting an appropriate polyimide from the above-described polyimide, or by selecting an appropriate copper foil or treatment condition from the copper foil or surface treatment conditions of the copper foil. Here, 180 degree peeling strength is specifically measured by the conditions described in the Example.

From the copper clad laminated board for COF, the method of manufacturing the film carrier tape for COF can select a well-known method suitably, and can use. For example, the copper-clad laminate for COF is cut into a film of a predetermined width, sprockets are provided on both sides of the film, a photosensitive resin layer is provided on the copper foil surface side, and exposed through a mask so as to obtain a predetermined circuit. , An etching process is performed, and either the unexposed portion or the exposed portion is removed. Next, there are methods such as a film carrier tape for COF by etching the exposed copper foil using the remaining resin layer as a resist to form a circuit pattern, and then removing the resist.

1 is a conceptual diagram showing an example of mounting an IC chip on a film carrier tape for COF, wherein the gold-plated bumps 2 of the IC chip 1 are formed on the polyimide layer 3 of the film carrier tape for COF. It shows the state bonded to the circuit 4 (The copper foil of the copper clad laminated board for COF is obtained by circuit-processing, and may be tin plating etc.). In this case, since it is thermocompression-bonded at the high temperature of about 350-400 degreeC, the thickness of the polyimide layer 3 of a crimp part will penetrate from initial thickness T1 to T2. It is preferable to make the difference T1-T2 of this thickness as small as possible.

(Example)

Hereinafter, an Example demonstrates this invention further in detail.

Abbreviations used in the examples are as follows.

PMDA: Anhydrous pyromellitic acid

BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic acid

m-TB: 4,4'-diamino-2,2'-dimethylbiphenyl

BAPP: 2,2-bis [4- (4-aminophenoxy) phenyl] propane

DAPE: 4,4'-diaminodiphenyl ether

MABA: 4,4'-diamino-2,2'-dimethoxy-benzanilide

DMAc: dimethylacetamide

Synthesis Example 1

In 425 g of DMAc, 21.78 g (102.63 × 10 ⁻³ mol) of m-TB and 13.70 g (68.42 × 10 ⁻³ mol) of DAPE were dissolved with stirring in a 1 L separate flask. Next, the PMDA to 29.55g (135.49 × 10 ^-3 mol) and ^{BPDA 9.96 (33.87 × 10 -3 mol} ) subjected to polymerization by introducing a little to the solution, to obtain a polyimide precursor solution A having a high viscosity.

Synthesis Example 2

To 110.5 kg of DMAc, 6651.3 g (25.85 mol) of MABA and 3450.9 g (17.23 mol) of DAPE were dissolved in a 130 L stainless vessel with stirring. Next, PMDA 9266.2g (42.48 mol) was added little by little to the solution to carry out a polymerization reaction to obtain a high viscosity polyimide precursor solution B.

Synthesis Example 3

BAPP 1294.43 (3.153 mol) was dissolved in 17386 g of DMAc, and then 708.49 g (3.248 mol) of PMDA was added to this solution to carry out a polymerization reaction to obtain a high viscosity polyimide precursor solution C.

The polyimide precursor solution obtained by each synthesis example was bar-coated on the heat resistant glass plate so that the film thickness after imide conversion might be set to 40 micrometers, and it dried at 130 degreeC for 5 minutes. Then, it put into the vacuum thermostat, heat-processed at 200 degreeC for 30 minutes, 300 degreeC for 30 minutes, and 350 degreeC for 30 minutes, and peeled from the glass plate, and obtained the polyimide film of 40 micrometers in thickness. Tg was measured by differential scanning calorimetry analysis (DSC) and thermomechanical analysis (TMA) of the obtained polyimide film, and viscoelasticity measurement was performed by dynamic mechanical analysis (Dynamic Mechanical Analysis).

Tg was not observed in the polyimide A obtained from the polyimide precursor solution A obtained in the synthesis example 1, and the storage elastic modulus in 350 degreeC was the non-thermoplastic polyimide of 1 GPa.

Tg was not observed in the polyimide B obtained from the polyimide precursor solution B obtained in Synthesis Example 2, and the storage modulus at 350 ° C. was a non-thermoplastic polyimide having 1 GPa.

In the polyimide C obtained from the polyimide precursor solution C obtained in Synthesis Example 3, Tg was observed between 300 ° C and 350 ° C, and the storage modulus at 350 ° C was 0.1 GPa of thermoplastic polyimide.

Processing Example 1

An unharmonized electrolytic copper foil having an average thickness of 18 µm was prepared, and the surface thereof was diluted with 30 ° C. diluted sulfuric acid to remove the oil component and the surface oxide film. Further, a nickel-zinc alloy layer was electrolyzed on the copper foil surface using a plating solution composed of nickel sulfate, zinc pyrolate, and potassium pyrolate.

Processing Example 2

An unharmonized electrolytic copper foil having an average thickness of 18 µm was prepared, and the surface thereof was diluted with 30 ° C. diluted sulfuric acid to remove the oil component and the surface oxide film. Further, a cobalt-nickel-zinc alloy layer was electrolyzed on the copper foil surface using a plating solution composed of nickel sulfate, zinc pyrrolate, potassium pyrolate, and cobalt sulfate.

Processing Example 3

A rough electrolytic copper foil having an average thickness of 18 µm was prepared, and the surface of the surface was diluted with 30 ° C diluted sulfuric acid to remove the oil component and the surface oxide film. In addition, a nickel-zinc-alloy layer was electrolyzed on the copper foil surface using a plating solution composed of nickel sulfate, zinc pyrolate, and potassium pyrolate.

Processing Example 4

Furthermore, the copper foil in which the metal treatment layer obtained by the process examples 1-3 was formed was washed with water, and an electrolytic solution of 2 g / L anhydrous sodium chromate dihydrate, a pH value of 4, and a bath temperature of 30 ° C. was used at a current density of 1 A / dm ² . An electrolytic chromated layer was formed for 5 seconds.

Processing Example 5

The three types of chromate-treated copper foils obtained in Process Example 4 were washed with water, immersed in 0.1 wt% aqueous solution of γ-glycidoxypropyltrimethoxysilane, which is a silane coupling agent, for 10 seconds, and immediately dried at 80 ° C. A treatment layer was formed. The obtained surface-treated copper foil is what was obtained from three types of copper foil which provided the metal treatment layer obtained by the process examples 1-3, and is called surface-treated copper foil 1, 2, 3 in order.

For surface treated copper foils 1 to 3, the surface roughness (Rz) is manufactured by KLA-Tencor Co., Ltd. based on the definition of the ten point average roughness of 5.1 in JIS B 0601-1994 "Definition and Display of Surface Roughness". P-15 was used to measure the measurement length at 0.8 mm, the measurement speed of 20 μm / sec, and the load of 2 g. As a result, both Rz of surface-treated copper foils 1 and 2 was 0.8 micrometer, and Rz of surface-treated copper foil 3 was 2.5 micrometers.

Example 1

The polyimide precursor solution A was bar-coated to the surface treatment copper foil 1 so that the film thickness after imide inversion might be set to 40 micrometers. Then, it dried for 5 minutes at 130 degreeC. Thereafter, the resultant was put in a vacuum thermostatic bath and heat treated at 200 ° C. for 30 minutes, at 300 ° C. for 30 minutes, and at 350 ° C. for 30 minutes to obtain a copper clad laminate having a thickness of 40 μm. The copper foil surface of this copper clad laminated board was observed with the optical microscope, and the groove | channel of the surface resulting from the pinhole and pinhole of 5 micrometers or more was measured. As a result, the number of pinholes and grooves (called the number of pinholes and the like) was 0 pieces / cm ² .

The copper-clad laminate was uniformly showered for 1 minute with an etching solution of 5.0 g / l sulfuric acid concentration, 50 g / l hydrogen peroxide and 20 g / l copper concentration, having a conductor thickness of 8.0 µm and a polyimide layer thickness of 40 µm. Copper clad laminates were obtained.

The copper foil of the copper clad laminate for COF was processed into a circuit having a width of 1 mm to measure 180 ° peeling strength with polyimide, which was 1.0 kN / m. Moreover, even after heat-processing this circuit at 150 degreeC for 168 hours in a hot air oven, it was 0.5 kN / m and it was confirmed that it is practical.

Examples 2-3 and Comparative Examples 1-4

A copper clad laminate for COF was obtained in the same manner as in Example 1 except that the kind of the surface-treated copper foil and the kind of the polyimide precursor solution were shown in Table 1. The result of having evaluated similarly to Example 1 about the obtained copper clad laminated board for COF is shown in Table 1. In addition, in Table 1, the kind of copper foil shows the kind of surface-treated copper foil, and the kind of polyimide shows the kind of polyimide precursor solution. Before peeling strength shows peeling strength before heat processing, and after peeling strength shows peeling strength after heat processing at 150 degreeC and 168 hours. In addition, micromachinability indicates the degree of 50 탆 pitch processing. The deformation amount represents the amount tested by the method described below.

Comparative Example 5

Table 1 shows the results of the same evaluation as above for the non-adhesive copper clad laminate by commercial sputter plating. Further, the polyimide layer of the non-adhesive copper clad laminate was immersed in an aqueous solution at 70 ° C. consisting of 33.5 g of water, 33.5 g of potassium hydroxide, 11 g of ethylenediamine, and 22 g of ethylene glycol for 3 hours to obtain a conductor layer. It was 0.8 micrometer when the roughness (Rz) of the surface of the conductor layer was measured.

Table 1

Copper foil type and Rz (㎛) Polyimide Type Pinhole, etc. (pcs / cm ² ) Before and after peeling strength (kN / m) Micro Machinability Strain amount (㎛) Example 1 1 (0.8) A 0 1 0.5 Good One Example 2 2 (0.8) A 0 1 0.8 Good One Example 3 1 (0.8) B 0 1 0.6 Good One Comparative Example 1 1 (0.8) C 0 1.2 1.0 Good 4 Comparative Example 2 3 (2.5) A 0 1.5 0.6 Partial paragraph - Comparative Example 3 1 (0.8) A 0 0.5 0.1 Circuit separation - Comparative Example 4 1 (0.8) A 0 0.5 0.1 Circuit separation - Comparative Example 5      (0.8) > 10 0.8 0.4 Partial circuit defect -

 Example 4

The sprocket hole was formed by punching about three types of copper clad laminated boards obtained in Examples 1-3 after slitting to 35 mm width. Next, using a photolithography method, the negative photoresist was applied and dried to form a photoresist layer on the copper foil, and the photoresist layer was patterned by exposure and development through a 50-μm pitch COF photomask. Subsequently, using the photoresist layer pattern as a mask, the copper foil layer was dissolved and removed with an aqueous ferric chloride solution to form a pattern of copper foil. In addition, the photoresist layer was removed by basic aqueous solution. When the obtained conductor layer pattern was observed, the favorable film carrier tape without a short circuit, disconnection, peeling, etc. was obtained. The obtained circuit was pickled with an aqueous sulfuric acid solution and then tin plated with Shipposit Company Tinposit LT-34 to obtain a tin plated film carrier tape.

Thereafter, an IC having gold bumps was mounted on the inner lead portion of the film carrier tape. Mounting was carried out using a flip chip bonder "TFC-2100" manufactured by Shivaura Mechatronics Corporation, so that the bonding head tool temperature was 400 ° C, the stage temperature was 100 ° C, and the bonding pressure was 20gf per bump.

Next, the cross section of the COF film carrier tape on which the IC was mounted was observed, and measured as T1 (film thickness) -T2 (mounting film thickness) = T3 (resin deformation due to mounting) shown in FIG. In this embodiment, the deformation amount T3 was all 1 µm, and the engagement state between the inner lead and the bump was good.

According to the present invention, it is possible to provide a copper-clad laminate for COF having no pinhole and having little wiring deviation even when chip mounting by Au-Au bonding or Au-Sn bonding. As needed, the copper clad laminated board for COF which enables underfill filling can be provided.

Claims (6)

A copper clad laminate provided with a polyimide layer on a copper foil, wherein the polyimide layer is obtained by coating, drying and curing in a solution state on the copper foil, exhibiting non-thermoplastic properties at 350 ° C., and the surface roughness of the polyimide laminated surface of the copper foil. (Rz) is in the range of 0.5 to 1.5 µm, and 180 ° peeling strength at room temperature between copper and polyimide is 0.6 kN / m or more. The copper clad laminate for COF according to claim 1, wherein the polyimide layer is a single layer. 3. The metal-treated layer according to claim 1, wherein the copper foil is a non-harmonized electrolytic copper foil, wherein the surface on the polyimide laminated side of the copper foil is treated with at least one metal selected from the group consisting of molybdenum, cobalt, nickel, and zinc; A copper clad laminate for COF, comprising a chromate treated layer and a silane coupling layer. The copper clad laminate for COF according to claim 3, wherein the metal treatment layer is an alloy layer comprising zinc and nickel as essential. The copper foil laminated sheet according to any one of claims 1 to 4, wherein the thickness of the copper foil is in the range of 5 to 20 µm, and the thickness of the polyimide layer is in the range of 5 to 50 µm. . The carrier tape for COF obtained by processing the copper clad laminated board for COF of any one of Claims 1-5.

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