JP2006278371A - Manufacturing method of polyimide-metal layer laminate, and the polyimide-metal layer laminate obtained thereby - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of polyimide-metal layer laminate that can satisfy the request of fan pattern machining, has high heat resistance and has improved dimensional stability, will not require pretreatment, or the like, especially before sputtering film formation, and has improved adhesion properties between a metal layer and a polyimide film, and to provide the polyimide-metal layer laminate obtained by the method. <P>SOLUTION: In the manufacturing method of the polyimide-metal layer laminate, a polyimide layer 2 is film-formed on metal foil by a casting method, and a metal layer 4 is formed on the metal foil-removed surface 3 of the polyimide film, obtained by removing the polyimide layer from the metal film by a sputtering method and an electrolytic plating method. The polyimide-metal layer laminate 5 is obtained by the manufacturing method. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a polyimide-metal layer laminate for use in a wiring board. Specifically, the present invention has excellent fine pattern workability of wiring, excellent adhesion between wiring and polyimide, and reliability. The present invention relates to a method for producing a polyimide-metal layer laminate that is high and suitable for a flexible wiring board, and a polyimide-metal layer laminate obtained by this method.

  For example, COF (Chip On Film), which is used in a wide range of fields such as liquid crystal drivers for mobile phones, increases the amount of processing information and the wiring pitch becomes narrower due to miniaturization, and the IC chip is mounted directly on the substrate wiring Therefore, there is an increasing demand for fine pattern workability, heat resistance, and the like for a two-layer CCL (Copper Clad Laminate) used as the material.

  The characteristics required for the two-layer CCL in order to satisfy fine pattern processability include wiring processability due to a flat polyimide-metal layer interface, electrical reliability for flowing a large amount of electrical signals with narrow pitch wiring, and Since the chip is mounted directly, it has heat resistance with adhesive strength that does not cause circuit peeling during mounting. In addition, a polyimide film as a two-layer CCL substrate is required to have dimensional stability, no variation in dimensional change rate within the film, and high heat resistance that can withstand thermocompression bonding during mounting.

  Due to its manufacturing method and characteristics, the two-layer CCL is made by a casting method (casting method) in which polyimide is applied on a copper foil, a laminating method in which a polyimide film is thermocompression bonded to a copper foil, a sputtering method or an electrolytic plating method on a polyimide film. It is classified as a sputter plating method for forming a layer.

  In particular, with regard to the sputter plating method, since the thickness of the metal layer can be freely controlled by electrolytic plating, the metal layer can be made thin, and the smoothness of the interface between polyimide and metal is good. It has the advantage that it is excellent in performance.

  However, in general, the polyimide film itself used in the sputter plating method is mainly manufactured by chemical imidization. After the varnish is applied on the drum and dried, the solvent is applied while being stretched in the state of a gel film. In order to evaporate, the orientation in one direction proceeds. In the polyimide film obtained by such a method, the thermal expansion coefficient in the MD and TD directions changes, and the dimensional change in the film may increase.

  The heat-resistant resin that can withstand thermocompression bonding is made of a resin having a rigid structure such as biphenyltetracarboxylic acid (BPDA) or p-phenylenediamine (p-DAP), which is mainly used in the laminating method. Although there are polyimide films and the like, since these have poor adhesion to the metal layer, if these resins are used in a sputter plating method with a small anchor effect, it is impossible to obtain an adhesive strength that can withstand practical use. Therefore, when using these resins in the sputter plating method, in order to improve the adhesion to the metal layer, the polyimide film before the metal layer is formed is subjected to dry treatment such as plasma treatment, alkali treatment, etc. It is necessary to improve the adhesion to the sputtered metal by performing a surface modification treatment such as by performing a wet treatment.

Thus, several solutions have been proposed so far in order to increase the adhesion of the polyimide film with poor adhesion to the metal layer. For example, according to Japanese Patent Application Laid-Open No. 2003-127275, it is described that a polyimide layer having heat resistance is subjected to reduced-pressure vacuum plasma treatment to improve adhesion with a metal layer. In Japanese Patent Laid-Open No. 06-210794, the surface of a polyimide film is subjected to surface modification by alkali treatment in order to develop adhesiveness. According to these prior arts, it is possible to develop an adhesive strength that can withstand practicality, but since various pretreatment steps are required, the treatment itself becomes complicated, and when a long treatment is performed, a polyimide film There is a possibility that the variation of the processing effect in the case becomes a problem.
JP 2003-127275 A Japanese Patent Laid-Open No. 06-210794

  The present invention satisfies the requirements for fan pattern processing, has high heat resistance and excellent dimensional stability, and further requires no pretreatment before sputtering film formation, etc. It is providing the manufacturing method of the polyimide-metal laminated body excellent in adhesiveness, and the polyimide-metal layer laminated body obtained by this method.

  As a result of intensive studies to solve such problems, the present inventors first formed a polyimide layer on a metal foil by a casting method in order to obtain a film having excellent dimensional stability, and then the polyimide layer was removed from the metal foil. By removing the polyimide film to obtain a polyimide film having a rigid structure with poor adhesion by forming a metal layer on the metal foil removal surface of the polyimide film by combining sputtering and electroplating. On the other hand, the present inventors have found that a metal layer having an adhesive force that can withstand practical use can be formed, thereby completing the present invention.

That is, in the present invention, a polyimide layer is formed on a metal foil by a casting method, and the polyimide layer obtained by removing the polyimide layer from the metal foil is coated with a metal layer by a sputtering method and an electroplating method. Is a method for producing a polyimide-metal layer laminate.
Moreover, this invention is a polyimide-metal layer laminated body obtained by said manufacturing method.

  According to the present invention, a polyimide film is formed on a metal foil by a casting method, and the polyimide film is formed by removing the polyimide layer from the metal foil. Therefore, a polyimide film having excellent dimensional stability can be obtained. In this case, in particular, by forming a polyimide layer using a monomer having a rigid structure as a basic skeleton, a polyimide film having high heat resistance can be obtained. By forming a metal layer on the surface by sputtering and electrolytic plating, it is excellent in adhesion between the metal layer and the polyimide layer without requiring pretreatment such as plasma treatment or alkali treatment on the polyimide film in advance. A polyimide-metal layer laminate can be obtained. And since such a polyimide-metal layer laminated body forms a metal layer by sputtering method and electroplating method, while being able to make the metal layer thin, smoothness of the interface between polyimide and metal is good. Therefore, it is excellent in fine pattern processability and can be suitably used for a flexible printed wiring board.

  Hereinafter, the present invention will be described in detail.

  In the present invention, first, in order to obtain a film having excellent dimensional stability, a polyamic acid solution, which is a polyimide precursor, is applied onto a metal foil by a casting method and dried to form a support substrate. After curing, the polyimide layer obtained by imidization is peeled off, or the metal foil is removed by means of dissolving with a commercially available etching solution or the like to obtain a polyimide film. Thus, since the polyamic acid solution is cured on the metal foil, a polyimide film that is not oriented in one direction without being affected by stretching can be obtained.

  In the present invention, the casting method refers to a known technique in which a polyimide layer is formed by applying a polyamic acid solution, which is a polyimide precursor, to the surface of a substrate such as a metal foil, followed by drying and curing. The acid solution and the coating amount can be appropriately selected, and as a method for applying the polyamic acid solution to the surface of the substrate, for example, a general coating method using hand coating, knife coater, lip coater or the like is used. be able to. Furthermore, about the polyamic acid apply | coated to the surface of metal foil, it can be made to imidize by drying and hardening with a general method, and a polyimide layer can be formed.

  About the polyimide layer formed by the casting method, it can obtain by making diamine and an acid anhydride react. In the present invention, polyimide means a resin made of a polymer having an imide group in the structure such as polyimide, polyamideimide, polyetherimide, polyesterimide, polysiloxaneimide, polybenzimidazoleimide and the like.

  As a means for reacting diamine and acid anhydride to form a polyimide layer, a known method can be employed. Preferably, first, a diamine component and an acid anhydride component are mixed in an approximately equimolar ratio in a solvent, and reacted in a reaction temperature range of 0 to 200 ° C., more preferably in a range of 0 to 100 ° C. to obtain a polyimide. It is preferable to form a polyimide layer made of a polyimide resin by obtaining a polyamic acid solution which is a resin precursor and further imidizing it. Here, examples of the solvent used in the reaction include N-methylpyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), and the like, and one or more kinds can be appropriately selected and used. .

  Examples of the acid anhydride component used in producing the polyamic acid used in the present invention include pyromellitic anhydride (PMDA), 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA). 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride (BTDA), 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride Among them, one or a mixture of two or more of them in any proportion can be used. Among these, the structure is particularly rigid and can exhibit high heat resistance. It is preferred to use BPDA.

  On the other hand, well-known diamines can be used as typical diamine components used in the production of the polyamic acid solution. For example, p-phenylenediamine (p-DAP), 4,4′-diaminodiphenyl ether, 2′-methoxy-4,4′-diaminobenzanilide, 1,4-bis (4-aminophenoxy) benzene, 1,3 -Bis (4-aminophenoxy) benzene, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-TB), 3 , 3′-dihydroxy-4,4′-diaminobiphenyl, 4,4′-diaminobenzanilide, etc., of which one or two or more of them are mixed in an arbitrary ratio Can do. In particular, in order to obtain a polyimide film having high heat resistance suitable for the application of the present invention, it is preferable to use m-TB having a rigid structure.

  As the metal foil to be a support base material when the polyimide layer is formed by the casting method, a metal foil such as copper, stainless steel, and aluminum foil can be used, but a copper foil is preferably used. The metal foil needs to be strong enough not to cause wrinkles or the like during resin coating. The appropriate thickness for this purpose is 8 to 70 μm, and preferably 9 to 30 μm. In addition, in order to obtain a smooth polyimide surface, the surface of the metal foil has a 10-point average roughness (JIS B 0601-1994: hereinafter referred to as Rz) Rz0 .8 μm or less. In addition, on the surface of the metal foil on the side where the polyimide layer is to be formed, at least one metal selected from metals such as Ni, Zn, Cr, Co and the like having high affinity with polyamic acid and polyimide is used. It is preferable that the metal precipitation process which precipitates is given. In general, these metals are known as metals having high affinity with polyimide, and in the present invention, when polyamic acid is applied to the metal foil, the metal foil has a structure that is compatible with this state. Since it is considered that the metal foil is maintained after removing the metal foil from the polyimide layer, it is presumed that the adhesion when the metal layer is formed by the sputtering method and the electrolytic plating method is improved.

  Examples of the metal deposition treatment for depositing a metal such as Ni, Zn, Cr, and Co on the surface of the metal foil include a rust prevention treatment using these metals. Examples of the method include performing a plating treatment using a bath containing a certain amount and depositing a metal on the surface of the metal foil.

In FIG. 1 (1)-(6), the procedure of the manufacturing method of the polyimide-metal layer laminated body of this invention is shown.
First, the polyamic acid solution which is a polyimide precursor is directly apply | coated to the surface of the support metal foil 1 (FIG. 1 (1)) used as a support base material, and it predrys by about 90-200 degreeC heat drying. Then, it is allowed to stand in a hot air drying furnace that can be set to a predetermined temperature for a certain period of time, or is continuously moved within the drying furnace area range to ensure a predetermined drying and curing time, whereby a heat treatment at a high temperature (200 The polyimide layer 2 is formed by imidizing the polyamic acid (FIG. 1 (2)). The heat treatment step is preferably performed under reduced pressure, a reducing gas atmosphere, or a reducing gas atmosphere under reduced pressure for the purpose of preventing oxidation of the supporting metal foil 1.

  Next, the polyimide layer 2 is removed from the support metal foil 1 with respect to the support metal foil 1 having the polyimide layer 2 formed on the surface (FIG. 1B). When the adhesiveness between the supporting metal foil 1 and the polyimide layer 2 is low and can be peeled off, it is peeled off by an appropriate method to obtain a polyimide film 2 consisting only of the polyimide layer 2. In the case where peeling is not possible, the supporting metal foil 1 is dissolved and removed with a commercially available etching solution such as ferric chloride, cupric chloride, sulfuric acid / hydrogen peroxide-based etching solution, etc. A polyimide film 2 is obtained (FIG. 1 (3)).

  Next, the metal layer 4 is newly formed by the sputtering method and the electrolytic plating method on the support metal foil removal surface 3 from which the support metal foil 1 of the polyimide film 2 obtained above is removed. The metal layer 4 may be formed by laminating one layer formed by a sputtering method and one layer formed by an electrolytic plating method, but preferably at least two layers are formed by a sputtering method in which the metal raw material is changed. After forming the above sputtering layer, it is preferable to further laminate one or more plating layers by electrolytic plating.

  1 (4) to (6), a first sputtering layer formed by sputtering in order from the support metal foil removal surface 3 to the metal layer 4 formed on the support metal foil removal surface 3 of the polyimide film 2. The case where 4a, the second sputtering layer 4b formed by the sputtering method, and the plating layer 4c formed by the electrolytic plating method are sequentially laminated is shown.

  As shown in FIG. 1 (4), first, the first sputtering layer 4 a formed on the support metal foil removal surface 3 of the polyimide film 2 is preferably nickel, from the viewpoint of ensuring adhesion with the polyimide film 2. It is good to form from 1 or more types of metals chosen from chromium and cobalt, or the alloy of these metals. The film thickness of the first sputtering layer 4a is preferably 1 to 40 nm, and more preferably 2.0 to 30 nm. When the film thickness is less than 1 nm, the adhesive strength between the metal layer 4 and the polyimide film 2 is lowered, and the adhesive strength after being exposed to a high-temperature and high-humidity environment is abruptly deteriorated so that the reliability as a laminate is improved. There is a risk that it cannot be maintained. On the other hand, if the thickness is larger than 40 nm, the etching property at the time of circuit processing deteriorates and the circuit processing step becomes complicated, and there is a concern that the electrical insulating property is lowered due to the etching residue.

  About the 2nd sputtering layer 4b laminated | stacked on the said 1st sputtering layer 4a shown in FIG.1 (5), since the electroconductivity at the time of electrolytic plating is favorable, forming from copper or a copper alloy is preferable. Good. The film thickness of the second sputtering layer 4b is preferably about 75 nm to 300 nm, more preferably about 150 to 250 nm from the viewpoint of forming a layer that can withstand the current density in the subsequent electroplating method. Good. If the thickness is less than 75 nm, the resistance becomes high at the time of subsequent electrolytic plating film formation, and defects such as burnout are likely to occur. On the contrary, if the thickness is more than 300 nm, the cost increases.

  In the present invention, for the sputtering method, DC (direct current) bipolar sputtering, DC tripolar sputtering, RF (radio frequency) sputtering, DC magnetron sputtering, RF magnetron sputtering, ion beam sputtering, or the like can be used. As for the gas used for sputtering, gas types such as helium, neon, argon, krypton, xenon, and nitrogen can be used, but the gas is easily available and does not react with metal during film formation. Argon gas is preferred. As for other sputtering conditions, a general method can be adopted.

  In addition, as a pre-process for forming a metal layer by sputtering, the polyimide film 2 may be heated in a drying furnace for the purpose of controlling the moisture content of the filmed polyimide. In order to carry out, it is good to heat at the temperature of room temperature-200 degreeC in a vacuum.

  Furthermore, plasma treatment, corona treatment, UV treatment, or the like may be applied to the sputter film formation surface before the step of forming the metal layer by sputtering. In addition to cleaning the support metal foil removal surface 3 of the polyimide film 2 to reduce pinholes and the like, it can be expected that the adhesive force is further improved by the surface modification effect.

  As shown in FIG. 1 (6), a plating layer 4c is further laminated on the second sputtering layer 4b formed above by an electrolytic plating method. The plating layer 4c is preferably a copper plating layer. The film thickness of the plating layer 4c can be set to an arbitrary thickness, but is preferably 3 to 15 μm. If the thickness of the plating layer is less than 3μm, the wiring height sufficient to mount the chip cannot be obtained. Conversely, if the thickness is greater than 15μm, the etching factor during wiring processing by etching decreases, and fine pattern processing It becomes difficult. Further, in the semi-additive method in which the circuit is formed by the plating method in FIG. 1 (5) formed up to the second sputtering layer, there is a concern that the circuit wiring strength is lowered particularly in the fine pattern when the thickness is larger than 15 μm.

  Regarding the electrolytic plating method in the present invention, a copper sulfate bath, a copper pyrophosphate bath, a copper cyanide bath, or the like can be used as a plating bath, preferably an electrolytic plating method in a copper sulfate bath, There are few decomposition products, and liquid management is easy. Moreover, about these plating baths, you may add an additive for the refinement | miniaturization of the crystal grain of the film | membrane which forms a plating layer, glossiness, leveling, and the uniformity of a film thickness. The additive is adsorbed on the cathode surface, obstructs the reaction on the cathode surface, and multinucleation of the crystal is performed, and it can be expected that the crystal is refined, glossed, improved in leveling, improved in physical properties, and improved in throwing power. A general method can be employed for other electrolytic plating conditions.

  As described above, the polyimide-metal layer laminate 5 having the structure of polyimide film 2 / first sputtering layer 4a / second sputtering layer 4b / plating layer 4c is obtained. The polyimide-metal layer laminate 5 thus obtained is coated with a polyamic acid solution on the surface of the supporting metal foil 1 and cured to obtain the polyimide layer 2, and the supporting metal foil 1 is removed by peeling or etching. Since the polyimide film 2 is obtained, the polyimide film 2 having excellent dimensional stability can be obtained. In this case, in particular, 3,3 ′, 4,4′-biphenyltetracarboxylic acid as described above is used. (BPDA) and 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB), a polyimide film made of a polyimide resin having a basic structure of a monomer having a rigid structure. High heat resistance that can sufficiently withstand thermocompression bonding can be provided. And the metal layer 4 is formed in the support metal foil removal surface 3 of this polyimide film 2 by sputtering method and electrolytic plating method. The support metal foil removal surface 3 of the polyimide film 2 is not directly affected by heat when cured and imidized compared to the opposite surface (surface opposite to the support metal foil removal surface). Therefore, the possibility of causing deterioration of the resin due to high temperature is reduced as much as possible, and the polyimide-metal layer laminate 5 having high adhesive force can be obtained. In particular, by forming the first sputtering layer 4a made of a predetermined metal raw material on the support metal foil removal surface 3 of the polyimide film 2, the adhesive force with the polyimide film 2 is secured and the metal layer 4 and the polyimide film 2 The adhesive strength is further improved. Preferably, the peel strength between the metal layer 4 and the polyimide film 2 when the wiring is formed on the metal layer 4 with a width of 1 mm is 800 N / mm or more.

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

[Synthesis example]
N, n-dimethylacetamide (DMAc) is placed in a reaction vessel capable of introducing a thermocouple, a stirrer and nitrogen. After this reaction vessel was put on ice water, 1,3-bis (4-aminophenoxy) benzene (TPE-R) and 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB) were added to the reaction vessel. Then, pyromellitic anhydride (PMDA) and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) were added. The total monomer charge was 15 wt%, and the molar ratio of acid anhydride to diamine was 0.97: 1.0. Thereafter, stirring was further continued, and the reaction vessel was removed from the ice water when the temperature in the reaction vessel was in the range of room temperature ± 5 ° C. Stirring was continued for 3 hours at room temperature to obtain a polyamic acid solution A.

As the supporting metal foil, a copper foil 1 (NA-VLP, 15 μm thickness, hereinafter referred to simply as “copper foil”) manufactured by Mitsui Mining & Mining Co., Ltd. was used. The copper foil 1 is subjected to a metal deposition treatment for depositing Ni, Zn, and Cr as surface metals on the resin coated surface. The amounts of precipitation of these surface metals were determined by atomic absorption spectrometry, and were Ni: 6 μg / cm ² , Zn: 2 μg / cm ² , and Cr: 0.5 μg / cm ² . After applying the polyamic acid solution A prepared in the synthesis example on the copper foil 1, it was dried by heating at 130 ° C. to remove the solvent. Then, it heat-processed from room temperature to 280 degreeC over about 4 hours, imidated, and obtained the single-sided copper clad laminated body in which the polyimide layer 2 with a thickness of about 25 micrometers was formed on copper foil.

The single-sided copper-clad laminate was etched with a ferric chloride solution to remove the copper foil, and a polyimide film 2 was obtained. A metal thin film was formed by setting in an RF magnetron sputtering apparatus so that a metal raw material was formed on the surface of the polyimide film 2 from which the copper foil was removed (copper foil removal surface 3). The inside of the tank in which the sample was set was depressurized to 3 × 10 ⁻⁴ Pa, argon gas was introduced to make the degree of vacuum 2 × 10 ⁻¹ Pa, and plasma was generated by an RF power source. The copper foil removal surface 3 of the polyimide film 2 so that the nickel: chromium alloy layer [ratio 8: 2, 99.9 wt%, hereinafter, the nichrome layer (first sputtering layer 4a)] has a film thickness of 30 nm by this plasma. A film was formed. After forming the nichrome layer, copper (99.99 wt%) was further formed on the nichrome layer by sputtering in the same atmosphere to form a second sputtering layer 4b.

Next, an 8 μm-thick copper plating layer (plating layer 4c) was formed in an electrolytic plating bath using the copper sputtered film (second sputtering layer 4b) as an electrode. As an electrolytic plating bath, a copper sulfate bath (copper sulfate 100 g / L, sulfuric acid 220 g / L, chlorine 40 mg / L, anode is phosphorous copper) is used, and a plating film is formed at a current density of 2.0 A / dm ² . did. After plating, it was washed with sufficient distilled water and dried.
In this way, a polyimide-metal laminate 5 composed of polyimide film 2 / nichrome layer 4a / copper sputter layer 4b / electroplated copper layer 4c was obtained.

  In order to evaluate the adhesive strength between the polyimide film 2 and the metal layer 4 formed by the sputter plating method, the electrolytic plated copper layer 4c is etched using a photoresist and ferric chloride to form a circuit pattern of 1 mmW. did.

  About the normal state peel strength of the obtained polyimide-metal laminated body 5, and the peel strength after 168 hours exposure at 150 degreeC air | atmosphere atmosphere, it measured by the peeling method. The measurement of the adhesive strength was evaluated at 90 degrees peel according to JIS C-6481.

  The adhesive strength between the polyimide film 2 and the metal layer 4 was 930 N / mm in a normal state and 870 N / mm after 150 ° C. and 168 hr treatment, and it was confirmed that the adhesive strength and the heat resistance retention were good. The results are shown in Table 1.

[Comparative Example 1]
Using the polyimide film 2 obtained by removing the copper foil of the single-sided copper-clad laminate in Example 1, the same method as in Example 1 on the surface opposite to the copper foil removal surface (non-copper foil contact surface) Thus, a laminate in which the nichrome layer 4a, the copper sputtered layer 4b, and the electroplated copper layer 4c were sequentially formed was obtained. This laminated body was evaluated in the same manner as in Example 1.
The adhesive strength between the polyimide film 2 and the metal layer 4 was 340 N / mm in a normal state, and 60 N / mm after 150 ° C. and 168 hr treatment, and sufficient adhesive strength was not obtained. The results are shown in Table 1.

[Comparative Example 2]
After applying the polyamic acid solution A obtained in the above synthesis example to a smooth glass plate, drying, and further heat-treating to form a polyimide layer, a polyimide film is obtained by peeling the polyimide layer from the glass plate. It was. A laminate was manufactured and evaluated in the same manner as in Example 1 except that the film was set on the sputtering surface so that the polyimide film was formed on the glass plate removal surface.
The adhesive strength between the polyimide and the metal was 80 N / mm in a normal state, and it was not adhered to such a degree that it could not be measured after the treatment at 150 ° C. for 168 hours. The results are shown in Table 1.

FIG. 1 is a side explanatory view showing a step of obtaining a polyimide-metal layer laminate by the production method of the present invention.

Explanation of symbols

1: Support metal foil 2: Polyimide layer (polyimide film)
3: Support metal foil removal surface 4: Metal layer
4a: First sputtering layer
4b: Second sputtering layer
4c: Plating layer 5: Polyimide-metal layer laminate

Claims (6)

  A polyimide layer is formed on a metal foil by a casting method, and this polyimide layer is removed from the metal foil. A metal layer is formed on the metal foil removal surface of the polyimide film obtained by sputtering and electrolytic plating. A method for producing a polyimide-metal layer laminate.   The surface of the metal foil on which the polyimide layer is formed by a casting method is subjected to a metal deposition treatment for depositing one or more metals selected from Ni, Zn, Cr and Co, and the metal foil The method for producing a polyimide-metal layer laminate according to claim 1, wherein the surface has a 10-point average roughness (hereinafter Rz) of 0.8 μm or less.   A first metal layer having a film thickness of 1 to 40 nm made of one or more metals selected from nickel, chromium and cobalt formed by sputtering or an alloy of these metals in order from the metal foil removal surface of the polyimide film. A sputtering layer, a second sputtering layer having a thickness of 75 to 300 nm made of copper or a copper alloy formed by sputtering, and a copper plating layer having a thickness of 3 to 15 μm formed by electrolytic plating are sequentially laminated. The manufacturing method of the polyimide-metal layer laminated body of Claim 1 or 2.   Among the polyimide raw materials forming the polyimide layer, the diamine component contains 2,2′-dimethyl-4,4′-diaminobiphenyl (m-TB), and the acid anhydride component is 3,3 ′, 4,4. The manufacturing method of the polyimide-metal layer laminated body in any one of Claims 1-3 containing '-biphenyltetracarboxylic dianhydride (BPDA).   A polyimide-metal layer laminate comprising a polyimide film and a metal layer obtained by the method for producing a polyimide-metal layer laminate according to claim 1.   The polyimide-metal layer laminate comprising a polyimide film and a metal layer according to claim 5, wherein the metal layer and the polyimide film have a peel strength of 800 N / mm or more when wiring is formed on the metal layer with a width of 1 mm.

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