JP5129171B2 - Method for manufacturing circuit wiring board - Google Patents

Description

  The present invention relates to a method for manufacturing a circuit wiring board used for an electronic component, and more particularly to a method for manufacturing a circuit wiring board formed by forming a circuit wiring having a predetermined pattern on a polyimide resin layer.

  In an electronic circuit of an electronic device, a printed wiring board obtained by processing a laminated board made of an insulating material and a conductive material is used. A printed wiring board is formed by fixing a conductive pattern based on electrical design on the surface (and inside) of an insulating substrate with a conductive material. Depending on the type of insulating resin used as a base material, a plate-shaped rigid printed wiring board And flexible printed wiring boards that are flexible. The flexible printed wiring board is characterized by having flexibility, and is a necessary part for connection in a movable part that constantly bends. In addition, since the flexible printed wiring board can be stored in a bent state in an electronic device, it is also used as a space-saving wiring material.

  In a flexible printed wiring board, a polyimide ester or a polyimide resin is often used as an insulating resin as a base material. However, the amount of heat-resistant polyimide resin is overwhelmingly large. On the other hand, copper foil is generally used as the conductive material because of its excellent conductivity.

  As a method for producing a flexible printed wiring board, first, a patterned conductor layer to be a wiring with a predetermined pattern is formed on an insulating resin layer made of a polyimide film or the like. Next, a protective resin layer is formed on the patterned conductor layer. That is, the surface of the patterned conductor layer is covered with a cover lay film made of a resin material to form a protective resin layer. Next, the surface of the patterned conductor layer exposed from the opening of the protective resin layer is subjected to plating, soldering, and the like, and further subjected to external processing to produce a flexible printed wiring board.

  As a representative method for producing a polyimide film used as an insulating resin layer in a flexible printed wiring board, a tenter method and a casting method can be given. The tenter method is a method in which a polyamic acid solution is cast on a rotating drum and dried, and then the polyamic acid layer is peeled off from the drum and cured to form a polyimide film (for example, Patent Document 1). The casting method is a method in which a polyamic acid solution is applied to an arbitrary support, cured by heat treatment, and then a polyimide resin layer is peeled from the support to form a polyimide film (for example, Patent Document 2 and Patent Document 3). ).

  Moreover, as a main manufacturing method of the patterned conductor layer as a circuit wiring, for example, a polyimide film is prepared, a seed layer is formed by sputtering a metal on this, and then a conductor layer is formed by copper plating. A method of forming a wiring by etching a conductor layer, a method of preparing a copper clad laminate (CCL) composed of a polyimide resin layer and a copper foil, and a method of forming a wiring by etching the copper foil layer (subtractive method) Etc. are done. A method (semi-additive method) is also known in which a seed layer is formed on a polyimide resin layer, a resist is patterned, and pattern plating is performed to form a wiring (semi-additive method).

  In recent years, a metal salt is formed by coordinating metal ions to polyamic acid, which is a precursor of polyimide resin, so that the adhesion between the polyimide resin substrate and the metal film can be maintained relatively well. A technique called a direct metallization method in which a metal thin film is formed by reduction has been proposed. A part of the metal thin film obtained by such a method is embedded in the resin of the polyimide resin base material, and high adhesion is obtained. There has been proposed a technique for applying such direct metallization to provide a flexible printed wiring board having excellent adhesion between a polyimide resin substrate and wiring (for example, Patent Document 4). However, this method is a method in which a polyimide substrate is treated with an alkali solution to form a modified layer, and then metal ions are adsorbed on the modified layer (hereinafter, this method may be referred to as an “alkali modifying method”). Therefore, there is a limit to the thickness of the resulting modified layer, and there is a drawback that the amount of metal ions that can be adsorbed in the modified layer cannot be increased. In addition, there is a restriction that it is necessary to select a polyimide having good compatibility (wetability) with an alkaline solution. Furthermore, in the alkali modification method, the polyamide base material is heated through the step of ring-closing treatment by heating the polyamic acid constituting the modified layer. There is a problem that the dimensional accuracy of the patterned conductor layer (wiring) is reduced due to shrinkage.

  Furthermore, as a method of forming the coverlay film on the surface of the patterned conductor layer, the patterned conductor layer is formed from a coverlay film made of a thermosetting resin having openings of a predetermined shape corresponding to the wiring. In general, a method of thermocompression-bonding to a metal-clad laminate is employed. However, there is a problem that the insulating resin layer is also thermally contracted by the heating in the coverlay process, and the dimensional accuracy of the patterned conductor layer fixedly formed thereon is lowered.

JP 2000-191806 A JP 2004-322441 A JP-A-7-76024 JP 2008-53682 A

  With recent miniaturization of electronic components and higher signal transmission speed, there is an increasing demand for fine fine pitch circuits in circuit wiring boards. As the wiring pitch becomes finer, interference is likely to occur between the wirings even if the wiring pattern has a slight dimensional error. However, in the manufacturing process of the circuit wiring board, since the heat treatment for the ring closure and imidization of the polyimide precursor and the coverlay processing is essential after the wiring formation as described above, the polyimide resin base material is thermally contracted, Wiring dimensions will change. Such a decrease in wiring dimensional accuracy is a major risk factor for reducing the yield and reliability of electronic components, and countermeasures have been demanded.

  Therefore, the present invention prevents a reduction in the dimensional accuracy of the patterned wiring caused by the heat treatment in the manufacturing process of the circuit wiring board, and has a fine fine pitch, a high dimensional accuracy, and the circuit wiring and the insulating resin layer. An object of the present invention is to provide a method for manufacturing a circuit wiring board having high adhesion reliability.

  As a result of intensive studies in view of the above circumstances, the present inventors have been able to suppress changes in wiring dimensions due to heat treatment by forming wiring while attaching a sheet-like support member to the insulating resin layer, and further, the sheet It has been found that a change in wiring dimensions can be further suppressed by forming an insulating resin layer by a casting method using a support member as a support, and the present invention has been completed.

That is, the present invention is a method of manufacturing a circuit wiring board formed by forming circuit wiring on an insulating resin layer,
a) Containing a polyimide precursor resin and a metal compound directly on a metal sheet-like support member or on a polyimide resin layer or a polyimide precursor resin layer supported by a metal sheet-like support member A step of forming a coating film by applying and drying the coating liquid to be applied;
b) forming a patterned resist mask on the surface of the coating film;
c) Metal ions in the coating film are treated with a reducing agent solution containing a boron compound to reduce the metal ions , thereby precipitating metal in a region not covered with the resist mask in the surface layer portion of the coating film. Forming a deposited layer;
d) forming a circuit wiring having a pattern on the metal deposition layer by electroless plating and / or electroplating;
e) imidizing the polyimide precursor resin in the coating film by heat treatment to form an insulating resin layer laminated on the sheet-like support member;
f) separating the sheet-like support member from the insulating resin layer ; and
g) A step of forming an insulating film by performing thermocompression bonding of a coverlay film on the layer above the wiring after performing the step e and before the step f.
Bei to give a,
The sheet-like support member has a surface roughness Rz that is in contact with the insulating resin layer and is long and less than 1.4 μm, and the steps are performed by a roll-to-roll method. It is a manufacturing method of a circuit wiring board.

  In the method for manufacturing a circuit wiring board of the present invention, in step b, the resist mask is formed by attaching a resist ink to a pattern shape surface of a mold having a pattern shape, and then forming a pattern of the mold with the resist ink. The shape surface may be brought into contact with the surface of the coating film so that a resist ink is adhered to the surface of the coating film.

  In the method for manufacturing a circuit wiring board according to the present invention, the sheet-like support member may be used as a means for maintaining the dimensional accuracy of the wiring.

In addition, in the method for manufacturing a circuit wiring board of the present invention, after step a, h) impregnation of the coating film with an aqueous solution containing metal ions and drying, so that the coating film contains metal ions. A step of increasing the amount, or i) a step of impregnating the coating film with an aqueous ammonia solution or an aqueous solution of a primary or secondary amine.

  According to the method for manufacturing a circuit wiring board of the present invention, the sheet-shaped support member is used as a support, the insulating resin layer is formed by a casting method, and the wiring formation step and heating are performed with the sheet-shaped support member provided. By performing the accompanying process, the thermal shrinkage of the insulating resin layer can be suppressed, so that the pattern accuracy of the wiring is maintained. Moreover, according to the method of the present invention, a circuit wiring having a high adhesion reliability between the circuit wiring and the insulating resin layer (polyimide resin layer) can be manufactured by forming the wiring by combining the casting method and the direct metallization method. .

  Moreover, in this invention, when producing an insulating resin layer by a casting method, the said sheet-like support member can be used as a support body used as the object which apply | coats polyimide precursor resin. And as above-mentioned, this sheet-like support member can be utilized also as a pattern dimension precision maintenance means in the process with a wiring formation process and a heating. In other words, each sheet-like support member has a function as a support in the casting method, a function to reinforce the insulating resin layer, and a function to maintain the dimensional accuracy of the wiring pattern. Compared to the case of using, it is possible to reduce the number of parts used and the number of processes such as laminating and peeling.

  In particular, in the formation of the resist mask in step b, when a mold having a pattern shape surface with resist ink is used, ultrafine wiring having a width of several μm that cannot be covered by the photolithography technique as in the prior art is formed. It is possible to maintain the wiring dimension accuracy in the ultra-fine wiring. That is, the method of the present invention is particularly effective when forming a fine pitch wiring of about 1 to 10 μm, for example, using a mold having a pattern-shaped surface.

It is drawing explaining the difference of the process of this invention method and the conventional method.

  Hereinafter, embodiments of the present invention will be described in detail. The manufacturing method of the circuit wiring board of this invention is equipped with the following processes af, and can further provide arbitrary processes, such as process g, h, i, as needed. The circuit wiring board manufactured by the manufacturing method of the present invention is formed by forming circuit wiring on an insulating resin layer.

Step a) A polyimide precursor resin and a metal compound are directly applied on a metal sheet-like support member or on a polyimide resin layer or a polyimide precursor resin layer supported by a metal sheet-like support member. A step of forming a coating film by coating and drying the coating solution contained:
The sheet-like support member used in the present invention is used for the purpose of reinforcing the insulating resin layer and the purpose of maintaining the dimensional accuracy of the wiring pattern by suppressing expansion and contraction due to heat of the insulating resin layer. Further, when the insulating resin layer is formed by the casting method, it becomes a target to which the resin liquid is applied, and also functions as a support for spreading the resin liquid. The sheet-like support member can be used in the form of a cut sheet, a roll, or an endless belt. In order to obtain productivity, it is efficient to use a roll-like or endless belt-like form so that continuous production is possible. Furthermore, the sheet-like support member is preferably a roll formed in a long form from the viewpoint of more greatly improving the effect of improving the wiring pattern accuracy in the circuit wiring board.

  The material of the sheet-like support member may have a thermal shrinkage rate of 500 ppm or less from the viewpoint of stability against heating when imidizing the polyimide precursor resin in forming the insulating resin layer or thermocompression bonding of the coverlay film. It is necessary and is preferably in the range of 0 to 300 ppm, and specifically, it is preferably a metal. When the thermal shrinkage rate is greater than 500 ppm, a dimensional change before and after heating occurs, the dimensional change of the wiring formed in the insulating resin layer cannot be suppressed, and the effect of maintaining the dimensional accuracy of the wiring cannot be obtained. In addition, from the viewpoint of chemical resistance when forming the wiring, the material of the sheet-like support member is preferably a metal. Therefore, as a sheet-like support member, a metal film such as copper foil, stainless steel foil, iron foil, nickel foil, beryllium foil, aluminum foil, zinc foil, indium foil, silver foil, gold foil, tin foil, zirconium foil, tantalum foil , Titanium foil, lead foil, magnesium foil, manganese foil and alloy foils thereof. Among these, copper foil or a copper alloy is particularly preferable when the insulating resin layer is produced by a casting method because, for example, the balance of operability in the polyimide precursor solution coating process, drying / heat treatment process and peeling process is good. . On the other hand, for example, when a polyimide film is used as a support, it shrinks due to heat treatment or the like, and the upper insulating resin layer (for example, polyimide resin layer) is pulled to it, so that the dimensional accuracy of the wiring is lowered. Therefore, synthetic resin cannot be applied as the material for the sheet-like support member.

  In consideration of the rigid surface, the sheet-like support member preferably has a thickness in the range of 6 μm to 70 μm, and more preferably in the range of 12 μm to 35 μm. If the thickness of the sheet-like support member is less than 6 μm, sufficient rigidity cannot be obtained, and if it exceeds 70 μm, separation (peeling) from the insulating resin layer may be difficult.

  In consideration of separability (peelability) from the insulating resin layer, the surface roughness Rz of the sheet-like support member on the surface side in contact with the insulating resin layer is preferably less than 1.4 μm, more preferably 1.2 μm or less. It is better to use something. By using the thing of such a range, the external appearance of the insulating resin layer after peeling can be made favorable. In particular, it is preferable to apply the step of casting and applying a polyimide precursor solution to a sheet-like support member and peeling the polyimide resin layer cured by heat treatment, because the above-described effect is easily obtained. The surface roughness Rz represents “10-point average roughness” and is measured according to JIS B 0601. From another viewpoint, when a water droplet is placed on the surface on the surface side in contact with the insulating resin layer, a sheet-like support member having a contact angle between the sheet-like support member and water exceeding 60 ° and 170 ° or less is used. It is good. More preferably, the contact angle with water is 70 ° or more and 100 ° or less. This contact angle is determined by two factors: the surface chemistry of the sheet-like support member and the surface roughness. When the contact angle exceeds the above range, the adhesive strength between the sheet-like support member and the insulating resin layer becomes excessively high, and not only the handling property at the time of peeling of the insulating resin layer is deteriorated, but also the appearance of the insulating resin layer after peeling. Tends to get worse.

  In the present invention, the resin constituting the insulating resin layer is a polyimide resin. Examples of the polyimide resin include a heat resistant resin made of a polymer having an imide group in a structure such as polyimide, polyamideimide, polybenzimidazole, polyimide ester, polyetherimide, and polysiloxaneimide.

  The polyimide resin can be formed by imidizing (curing) a precursor. The precursor here contains a photosensitive group, for example, an ethylenically unsaturated hydrocarbon group, in its molecular skeleton. Also included. Details of imidization will be described later.

  As the polyimide precursor resin (hereinafter sometimes simply referred to as “precursor”), a known polyimide resin precursor obtained from a known acid anhydride and diamine can be applied and can be produced by a known method. . The precursor can be obtained, for example, by dissolving tetracarboxylic dianhydride and diamine in an organic solvent in an approximately equimolar amount and stirring the mixture at a temperature in the range of 0 to 100 ° C. for 30 minutes to 24 hours to cause a polymerization reaction. . In the reaction, it is preferable to dissolve the reaction components so that the obtained precursor is in the range of 5 to 30% by weight, preferably in the range of 10 to 20% by weight, in the organic solvent. As the organic solvent used for the polymerization reaction, it is preferable to use a polar one. Examples of the organic polar solvent include N, N-dimethylformamide, N, N-dimethylacetamide (DMAc), N-methyl. Examples include 2-pyrrolidone, 2-butanone, dimethyl sulfoxide, dimethyl sulfate, cyclohexanone, dioxane, tetrahydrofuran, diglyme, and triglyme. Two or more of these solvents can be used in combination, and some aromatic hydrocarbons such as xylene and toluene can also be used.

  The synthesized precursor is used as a solution. Usually, it is advantageous to use as a reaction solvent solution, but if necessary, it can be concentrated, diluted or replaced with another organic solvent. Moreover, since a precursor is generally excellent in solvent solubility, it is advantageously used. The solution thus prepared can be used as a coating solution by adding a metal compound.

  The precursor is preferably selected to include a thermoplastic polyimide resin after imidization. By using a thermoplastic resin, it is possible to improve the adhesion with a metal deposition layer (described later). Such a thermoplastic polyimide resin preferably has a glass transition temperature of 350 ° C. or lower, more preferably 200 to 320 ° C.

As a precursor of a thermoplastic polyimide resin, what has a structural unit represented by following General formula (1) is preferable. In Formula (1), Ar ₁ represents a divalent aromatic group represented by Formula (2), Formula (3), or Formula (4), and Ar ₂ is represented by Formula (5) or Formula (6). Represents a tetravalent aromatic group. In Formula (2) to Formula (4), R ₁ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, X and W are independently a single bond, 2 having 1 to 15 carbon atoms. A divalent hydrocarbon group, —O—, —S—, —CO—, —SO ₂ —, —NH— or —CONH—, wherein n ₁ is an integer of 0 to 4 independently P represents the molar ratio of the constituent units and is a value in the range of 0.1 to 1.0.

In the general formula (1), Ar ₁ can be referred to as a diamine residue, and Ar ₂ can be referred to as an acid anhydride residue. Therefore, a preferred polyimide resin will be described using a diamine and an acid anhydride. However, the precursor of the thermoplastic polyimide resin is not limited to that obtained by this method.

Examples of diamines suitably used for preparing a thermoplastic polyimide resin precursor include 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'-diamino Biphenyl, 3,3′-dihydroxy-4,4′-diaminobiphenyl, 4,4′-diaminobenzanilide and the like can be mentioned. In addition, the diamine mentioned by description of the low thermal expansion polyimide resin mentioned later can be used. Among them, particularly preferred diamine components include 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane (DANPG), 2,2-bis [4- (4-aminophenoxy) phenyl] propane ( BAPP), 1,3-bis (3-aminophenoxy) benzene (APB), paraphenylenediamine (p-PDA), 3,4'-diaminodiphenyl ether (DAPE34), 4,4'-diaminodiphenyl ether (DAPE44) One or more selected diamines may be mentioned.

  Examples of the acid anhydride suitably used for the preparation of the thermoplastic polyimide resin precursor include pyromellitic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, and 3,3 ′. 4,4'-diphenylsulfone tetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride. In addition, the acid anhydrides mentioned in the description of the low thermal expansion polyimide resin described later can be used. Among them, particularly preferred acid anhydrides include pyromellitic anhydride (PMDA), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3', 4,4'- Examples thereof include at least one acid anhydride selected from benzophenone tetracarboxylic dianhydride (BTDA) and 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride (DSDA).

  Each of the diamine and acid anhydride may be used alone or in combination of two or more. In addition, diamines and acid anhydrides other than those described above can be used in combination.

  In the precursor of the thermoplastic polyimide resin, the structural unit represented by the general formula (1) may be present in the homopolymer or may be present as a structural unit of the copolymer. In the case of a copolymer having a plurality of structural units, it may exist as a block copolymer or a random copolymer. The structural unit represented by the formula (1) is plural, but may be one type or two or more types. Advantageously, the main component is the structural unit represented by the formula (1), and the precursor preferably contains 60 mol% or more, more preferably 80 mol% or more.

  In this Embodiment, in order to prepare a coating liquid, a commercial item can also be used suitably as a solution containing a precursor. For example, Nippon Steel Chemical Co., Ltd. thermoplastic polyimide precursor resin varnish SPI-200N (trade name), SPI-300N (trade name), SPI-1000G (trade name), Toray Industries Co., Ltd. 3000 (trade name) and the like.

  As the metal compound contained in the coating solution together with the precursor, a compound containing a metal species having a redox potential higher than the redox potential of the reducing agent used in the reduction treatment (described later) for forming a metal deposition layer, It can be used without particular limitation. Examples of the metal compound include those containing metal species such as Cu, Ni, Pd, Ag, Au, Pt, Sn, Fe, Co, Cr, Rh, and Ru. As the metal compound, a salt of the metal, an organic carbonyl complex, or the like can be used. Examples of the metal salt include hydrochloride, sulfate, acetate, oxalate, and citrate. Metal salts are preferably used when the metal is Cu, Ni or Pd. Examples of the organic carbonyl compound capable of forming an organic carbonyl complex with the above metal species include β-diketones such as acetylacetone, benzoylacetone and dibenzoylmethane, and β-ketocarboxylic acid esters such as ethyl acetoacetate. it can.

Preferred specific examples of the metal _{compound, Ni (CH 3 COO) 2} , Cu (CH 3 COO) 2, Pd (CH 3 COO) 2, NiSO 4, CuSO 4, PdSO 4, NiCO 3, CuCO 3, PdCO 3 , NiCl ₂ , CuCl ₂ , PdCl ₂ , NiBr ₂ , CuBr ₂ , PdBr ₂ , Ni (NO ₃ ) ₂ , NiC ₂ O ₄ , Ni (H ₂ PO ₂ ) ₂ , Cu (NH ₄ ) ₂ Cl ₄ , CuI Cu (NO ₃ ) ₂ , Pd (NO ₃ ) ₂ , Ni (CH ₃ COCH ₂ COCH ₃ ) ₂ , Cu (CH ₃ COCH ₂ COCH ₃ ) ₂ , Pd (CH ₃ COCH ₂ COCH ₃ ) _{2 and the} like. be able to.

  In the coating solution containing the precursor and the metal compound, a three-dimensional cross-linking reaction occurs between the metal ion generated by dissociation of the metal compound and the precursor. For this reason, the thickening and gelation of the coating solution proceed with the passage of time, which may make it difficult to use the coating solution. In order to prevent such thickening and gelation, it is preferable to add a viscosity modifier as a stabilizer in the coating solution. By adding the viscosity modifier, the viscosity modifier and the metal ion form a chelate complex instead of the metal ion in the coating solution forming a chelate complex with the precursor. As described above, the viscosity modifier blocks the three-dimensional cross-linking between the precursor and the metal ion, and suppresses thickening and gelation.

  As the viscosity modifier, it is preferable to select a low-molecular organic compound that is highly reactive with metal ions (that is, capable of forming a metal complex). The molecular weight of the low molecular weight organic compound is preferably in the range of 50 to 300. Specific examples of such a viscosity modifier include acetylacetone, ethyl acetoacetate, pyridine, imidazole, picoline and the like. Moreover, it is preferable to add the addition amount of a viscosity modifier in the range of 1-50 mol with respect to 1 mol of chelate complex compounds which can be formed, Preferably it is in the range of 2-20 mol.

  The compounding amount of the metal compound in the coating solution is within the range of 5 to 60 parts by weight, preferably within the range of 10 to 40 parts by weight, with respect to 100 parts by weight of the total of the precursor, the metal compound and the viscosity modifier. To be. In this case, if the metal compound is less than 5 parts by weight, the reduction of metal particles on the surface of the polyimide precursor resin layer is reduced by the reduction treatment, resulting in unevenness in the thickness of the conductor layer (for example, electroless plating layer), This is because if it exceeds 60 parts by weight, a metal salt that cannot be dissolved in the coating solution will precipitate.

  In addition, a leveling agent, an antifoamer, adhesiveness imparting agent, a crosslinking agent etc. can be mix | blended with the coating liquid as arbitrary components other than the said component, for example.

  The method for applying the coating liquid is not particularly limited, and for example, it can be applied with a coater such as a comma, die, knife, lip or the like.

Moreover, after apply | coating a coating liquid, it is made to dry and a coating film is formed. In drying, the temperature is controlled so as not to complete imidization due to the progress of dehydration and ring closure of the precursor. The drying method is not particularly limited, and for example, the drying may be performed under a temperature condition in the range of 60 to 200 ° C. over a time period in the range of 1 to 60 minutes, preferably 60 to 150 ° C. It is preferable to perform drying under temperature conditions within the range. The precursor layer after drying may have part of the precursor structure imidized, but the imidization rate should be 50% or less, more preferably 20% or less, leaving the precursor structure at 50% or more. Is good. In addition, the imidation ratio of the precursor is 1,000 cm by measuring the infrared absorption spectrum of the polyimide thin film by a transmission method using a Fourier transform infrared spectrophotometer (commercial product: FT / IR620 manufactured by JASCO Corporation). ^-1 benzene ring carbon hydrogen bond as a reference is calculated from the absorbance from the imide groups 1,710Cm ^-1.

  The coating film may be a single layer or a laminated structure formed from a plurality of coating films. In the case of a plurality of layers, it can be formed by sequentially coating other precursors on precursor layers made of different constituent components. When the precursor layer is composed of three or more layers, the precursor having the same configuration may be used twice or more. Two layers or a single layer, in particular a single layer, having a simple layer structure can be advantageously obtained industrially. The thickness of the coating film (after drying) is preferably in the range of 3 to 100 μm, and preferably in the range of 3 to 50 μm.

  When forming a coating film composed of a plurality of layers, all layers may contain a metal compound, or only a part of the layers may contain a metal compound, but a circuit wiring is formed. It is preferable that the metal compound is contained only in the precursor layer on the side (outermost layer).

When the coating film is composed of a plurality of layers, it is preferable to form the precursor layer so that the polyimide resin layer in contact with the circuit wiring after imidization described later becomes a thermoplastic polyimide resin layer. Moreover, it is preferable to form at least one layer of the plurality of layers with a precursor layer that becomes a low thermal expansion polyimide resin after imidization. Applying such a low thermal expansion polyimide resin as an insulating resin layer is advantageous because warpage as a circuit wiring board can be suppressed. When the polyimide resin layer is composed of a low thermal expansion polyimide resin layer and a thermoplastic polyimide resin layer, 1/2 or more of the total thickness, preferably 2/3 to 9/10 is low thermal expansion polyimide resin It is better to make up with layers. Further, from the viewpoint of heat resistance and dimensional stability, the thickness of one layer of the thermoplastic polyimide resin layer is preferably 5 μm or less, and preferably in the range of 1 to 4 μm. The linear thermal expansion coefficient of the entire polyimide resin layer is 30 × 10 ⁻⁶ (1 / K) or less, preferably 5 × 10 ^{−6 to} 25 × 10 ⁻⁶ (1 / K). .

Specifically, the low thermal expansion polyimide resin has a linear thermal expansion coefficient in the range of 1 × 10 ⁻⁶ to 30 × 10 ⁻⁶ (1 / K), preferably 1 × 10 ^{−6 to} 25 × 10 ^{−. 6} (1 / K), more preferably 15 × 10 ^{−6 to} 25 × 10 ⁻⁶ (1 / K). Such a low thermal expansion polyimide resin is preferably a polyimide resin having a structural unit represented by the following general formula (7). In Formula (7), Ar ₃ represents a tetravalent aromatic group represented by Formula (8) or Formula (9), and Ar ₄ represents a divalent group represented by Formula (10) or Formula (11). Represents an aromatic group, R ₂ independently represents a monovalent hydrocarbon group or alkoxy group having 1 to 6 carbon atoms, and V and Y independently represent a single bond or a divalent hydrocarbon group having 1 to 15 carbon atoms. , O, S, CO, SO, SO ₂ or CONH represents a divalent group, m ₁ independently represents an integer of 0 to 4, q represents a molar ratio of constituent units, 0.1 It is in the range of -1.0.

  The structural unit may be present in the homopolymer or may be present as a structural unit of the copolymer. In the case of a copolymer having a plurality of structural units, it may exist as a block copolymer or a random copolymer.

In the general formula (7), Ar ₃ can be referred to as an acid anhydride residue, and Ar ₄ can be referred to as a diamine residue. Therefore, a preferred polyimide resin will be described using an acid anhydride and a diamine. However, the low thermal expansion polyimide resin is not limited to that obtained by this method.

  Acid anhydrides used to form low thermal expansion polyimide resins include pyromellitic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3', 4,4'- Preferred examples include diphenylsulfonetetracarboxylic dianhydride and 4,4′-oxydiphthalic anhydride. Moreover, 2,2 ', 3,3'-, 2,3,3', 4'- or 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 2,3 ', 3,4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 2,3 ', 3,4'-diphenyl ether tetracarboxylic dianhydride Bis (2,3-dicarboxyphenyl) ether dianhydride and the like are also preferred. In addition, 3,3``, 4,4 ''-, 2,3,3 '', 4 ''-or 2,2 '', 3,3 ''-p-terphenyltetra Carboxylic dianhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3- or 3.4-dicarboxyphenyl) methane dianhydride, bis Preferred examples include (2,3- or 3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3- or 3,4-dicarboxyphenyl) ethane dianhydride and the like.

  Other acid anhydrides such as 1,2,7,8-, 1,2,6,7- or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, 2,3,6,7 -Anthracene tetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) tetrafluoropropane dianhydride, 2,3,5,6-cyclohexane dianhydride, 2,3,6,7 -Naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,8-dimethyl-1,2 , 3,5,6,7-Hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6- or 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic Acid dianhydride, 2,3,6,7- (or 1,4,5,8-) tetrachloronaphthalene-1,4,5,8- (or 2,3,6,7-) tetracarboxylic acid Dianhydride, 2,3,8,9-, 3,4,9,10-, 4,5,10,11- or 5,6,11,12-perylene-tetracarboxylic dianhydride, cyclopentane -1,2,3,4-teto Lacarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, thiophene-2,3,4,5- Examples thereof include tetracarboxylic dianhydride and 4,4′-bis (2,3-dicarboxyphenoxy) diphenylmethane dianhydride.

  Diamines used to form low thermal expansion polyimide resins include 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, 3,3 Preferred examples include '-dihydroxy-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide and the like. Diamines include 2,2-bis- [4- (3-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, and bis [4- (3-aminophenoxy) phenyl. ] Sulfone, bis [4- (4-aminophenoxy)] biphenyl, bis [4- (3-aminophenoxy) biphenyl, bis [1- (4-aminophenoxy)] biphenyl, bis [1- (3-aminophenoxy) )] Biphenyl, bis [4- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy)] benzophenone, bis [4- (3-aminophenoxy)] benzophenone, bis [4,4 '-(4-aminophenoxy)] Ben Anilide, bis [4,4 '-(3-aminophenoxy)] benzanilide, 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene, 9,9-bis [4- (3-aminophenoxy) Preferred examples include phenyl] fluorene and the like.

  Other diamines include, for example, 2,2-bis- [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis- [4- (3-aminophenoxy) phenyl] hexafluoropropane, 4 , 4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline, 4,4'-diaminodiphenylpropane, 3,3 ' -Diaminodiphenylpropane, 4,4'-diaminodiphenylethane, 3,3'-diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 3, 3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 3,4'-diaminodiphenyl Ether, benzidine, 3,3'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 4,4 ''-diamino-p-terphenyl, 3, 3 ''-diamino-p-terphenyl, m-phenylenediamine, p-phenylenediamine, 2,6-diaminopyridine, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-amino) Phenoxy) benzene, 4,4 '-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 4,4'-[1,3-phenylenebis (1-methylethylidene)] bisaniline, bis (p- Aminocyclohexyl) methane, bis (p-β-amino-t-butylphenyl) ether, bis (p-β-methyl-δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-aminopentyl) benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene 2,4-bis (β-amino-t-butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine, Examples thereof include p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-diamino-1,3,4-oxadiazole, piperazine and the like.

  Each of acid anhydrides and diamines can be used alone or in combination of two or more. In addition, other acid anhydrides or diamines not included in the general formula (7) can be used together with the acid anhydrides or diamines. In this case, other acids not included in the general formula (7) The proportion of anhydride or diamine used is 90 mol% or less, preferably 50 mol% or less. By controlling the types of acid anhydrides or diamines and the molar ratios when using two or more acid anhydrides or diamines, the thermal expansion, adhesion, glass transition point (Tg), etc. are controlled. be able to.

  As the precursor solution of the non-thermoplastic polyimide resin, a commercially available product can be suitably used. For example, U-Varnish-A (trade name) which is a non-thermoplastic polyimide precursor resin varnish manufactured by Ube Industries, Ltd. U-varnish-S (brand name) etc. are mentioned.

  Further, a single layer or a plurality of precursor layers are laminated on a sheet-like support member, and after imidization is made into a single layer or a plurality of polyimide resin layers, a coating film is further formed thereon. It is also possible. In this case, in order to improve the adhesion between the polyimide resin layer and the coating film layer, the surface of the polyimide resin layer is preferably surface-treated with plasma. By this surface treatment with plasma, the surface of the polyimide resin layer can be roughened or the chemical structure of the surface can be changed. Thereby, the wettability of the surface of the polyimide resin layer is improved, the affinity with the precursor solution is increased, and the coating film can be stably held on the surface.

  As the plasma, for example, an atmospheric pressure type plasma processing apparatus is used, and plasma of argon, helium, nitrogen, or a mixed gas thereof is generated in a vacuum processing chamber. In this case, it is preferable that the processing pressure is in the range of 5000 to 200000 Pa, the processing temperature is in the range of 10 to 40 ° C., and the high frequency (or microwave) output is in the range of 50 to 400 W. In addition, hydrolysis of the polyimide resin by alkali treatment is effective because it can improve the adhesion to the coating film. Here, examples of the alkali include alkali metal hydroxides such as LiOH, KOH, and NaOH, and preferably one or more selected from KOH or NaOH can be used.

Step b) Step of forming a patterned resist mask on the surface of the coating film:
A known method can be applied to the formation of the resist pattern, and is not particularly limited. For example, it is possible to use a photolithography technique in which a photosensitive resist is laminated or coated on the surface of a coating film to form a resist layer, and then exposed, developed, and cured to form a resist pattern.

  In step b, the resist mask is formed by attaching a resist ink to the pattern shape surface of a mold having a pattern shape, and then bringing the pattern shape surface of the mold with the resist ink into contact with the surface of the coating film. It is preferable to carry out by attaching a resist ink to the surface of the coating film. In this method, the circuit wiring can be formed with a fine pitch within the range of 1 to 10 μm, preferably 2 to 5 μm.

  When adopting such a forming method, first, a mold is prepared in which resist ink is attached to the surface of the concavo-convex pattern. The mold having the concavo-convex pattern shape surface is used when the resist ink adhered to the convex portions of the pattern is transferred to the coating film. For this purpose, the template is preferably a material having good resist ink wettability and chemical resistance to the resist ink. For example, PDMS (polydimethylsiloxane), fluororesin, quartz, silicon oxide, Materials made of silicon carbide, glass, silicon, nickel, tantalum and the like can be suitably used. The mold may be composed of a single material or may be supported by a hard substrate. The concave / convex pattern of the mold can be formed by a known photolithography technique and etching. The pattern shape surface of the mold may be subjected to a plasma treatment or a treatment with a surface modifier in order to improve wettability with the resist ink.

  The mold has a concavo-convex pattern corresponding to the negative type of the patterned conductor layer (circuit wiring) of the circuit wiring board. The width of the concave portion (or the width of the convex portion) on the pattern shape surface of the mold is preferably 0.05 μm or more, and the depth of the concave portion (or the height of the convex portion) is 0.5 μm or more. preferable. By setting it as such a range, it can suppress that a pattern is crushed at the time of adhesion of the resist ink to a casting_mold | template, and the transfer to a resin layer. Depending on the application of the circuit wiring board, the width of each of the irregularities on the pattern surface in the mold can be arbitrarily changed within the above range. For example, in the flexible wiring board application, the width of the recess (or the protrusion The width is preferably in the range of 1 to 25 μm. Furthermore, the shape of the mold may be a flat plate for performing batch printing, or a roll for continuous printing.

  The resist ink contains an ink solute that forms a hydrophobic resist layer and a solvent for diluting it. In order to adjust the adhesion amount and transfer amount of resist ink, it is desirable to dilute with a solvent and adjust the concentration. It is preferable that the resist ink has good wettability with respect to the concave / convex pattern of the mold used for printing and can be uniformly attached to the resist ink. After volatilization of the solvent, it is liquid or semi-solid, and it is desirable to have fluidity and adhesiveness when transferring ink onto the coating film surface. After transferring the resist ink, it is desirable to fix it on the surface of the polyimide precursor resin by drying or heating to develop hydrophobicity.

  The ink solute has an organic functional group (for example, amino group, epoxy group, etc.) for chemically bonding with the polyimide resin and a hydrophobic group or chemical structure exhibiting water repellency in order to fix on the coating film surface and develop hydrophobicity. It is desirable. Specific examples of the ink solute include, for example, a terminal-modified silicone, a silane coupling agent, and an epoxy oligomer. This will be described in order below.

<Terminal modified silicone>
The terminal-modified silicone is amino-modified or epoxy-modified silicone, and as shown below, the functional group may be introduced into any of a side chain, one end, both ends, and a side chain both ends type. The side chain type represented by the general formula (12) is obtained by introducing an organic modifying group into the side chain of polysiloxane. The single terminal type represented by the general formula (13) is obtained by introducing an organic modifying group into one terminal of polysiloxane. The both-end type represented by the general formula (14) is obtained by introducing an organic modifying group at both ends of the polysiloxane. The side chain double-end type represented by the general formula (15) is one in which organic modifying groups are introduced into both the side chain and both ends of the polysiloxane.

In the general formulas (12) to (15), R ₃ means an organic modifying group having an amino group or an epoxy group shown below, and R ₃ ′ means a hydrocarbon group, which is an average number of repetitions. m ₂ and n ₂ each represent a number of 1 to 20, preferably 5 to 15.

［ここで、アミノ基、エポキシ基に結合する基Ｒ_４としては、例えばプロピル基、ブチル基、フェニル基、フェニルメチルエーテル基などが挙げられる］

[Examples of the group R ₄ bonded to an amino group or an epoxy group include a propyl group, a butyl group, a phenyl group, and a phenylmethyl ether group]

  Examples of the main chain siloxane skeleton include dimethylsiloxane, diphenylsiloxane, and methylphenylsiloxane. The molecular weight of silicone is preferably 800 or less, more preferably 500 or less per functional group.

  Examples of such modified silicones include diaminopropylpolydimethylsiloxane, diaminopropylpolydiphenylsiloxane, diglycidoxypropylpropylpolydimethylsiloxane, diglycidoxypropylpropylpolydiphenylsiloxane, and the like.

  As the amino-modified silicone, diaminosiloxane represented by the following general formula (16) is preferably used as the diaminosiloxane having both ends.

［但し、Ａｒ_５及びＡｒ_６は、それぞれ、酸素原子を含有していてもよい２価の有機基を示し、Ｒ_５〜Ｒ_８は、それぞれ炭素数１〜６の炭化水素基を示し、平均繰り返し数であるｍ_３は、１〜２０、好ましくは５〜１５の数を意味する。

[However, Ar ₅ and Ar ₆ each represent a divalent organic group that may contain an oxygen atom, R _{5 to} R ₈ each represent a hydrocarbon group having 1 to 6 carbon atoms, and average M ₃ which is a repeating number means a number of 1 to 20, preferably 5 to 15.

As a specific example of the diaminosiloxane represented by the general formula (16), a diaminosiloxane represented by the following formula is preferable. In the following formula, m ₃ has the same meaning as described above.

  Typical solvents for the solution containing the modified silicone (resist ink) include, for example, ether solvents such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane, acetone, MEK (methyl ethyl ketone), 2-pentanone, 3- Mention may be made of ketone solvents such as pentanone and γ-butyrolactone, and aromatic hydrocarbon solvents such as toluene and xylene. These may be used alone or in combination of several kinds. Particularly preferred is toluene. The concentration of the modified silicone in the solution containing the terminal-modified silicone (resist ink) is preferably from 0.1 to 5% by weight, more preferably from 0.5 to 1% by weight.

<Silane coupling agent>
Examples of the silane coupling agent having an amino group as an organic functional group include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, etc. Can be mentioned. These can be used alone or in combination of two or more.

  Examples of the silane coupling agent having an epoxy group as an organic functional group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidide. Examples include xylpropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. These can be used alone or in combination of two or more.

  Among these, 3-aminopropyltriethoxysilane and / or 3-aminopropyltrimethoxysilane are particularly preferable.

  The silane coupling agent is used as an organic solvent solution (resist ink). The organic solvent is not particularly limited as long as it is a liquid that can dissolve the silane coupling agent. Examples of such an organic solvent include alcohol solvents such as methanol, ethanol, propanol, and isopropanol, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, Amide solvents such as N, N-dimethylmethoxyacetamide, dimethyl sulfoxide and N-methyl-2-pyrrolidone, ether solvents such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether and dioxane, acetone, MEK (methyl ethyl ketone), 2-pentanone And ketone solvents such as 3-pentanone and γ-butyrolactone, and aromatic hydrocarbon solvents such as toluene and xylene. The concentration of the silane coupling agent in the solution (resist ink) containing the silane coupling agent is preferably 0.1 to 5% by weight, and more preferably 0.5 to 1% by weight.

<Epoxy oligomer>
The epoxy oligomer used in the present invention is not particularly limited, and examples thereof include epoxy oligomers such as bisphenol A type, bisphenol F type, biphenyl type, and cresol novolac type. These may be used alone or in combination of two or more. Can be used. The epoxy oligomer preferably has an epoxy equivalent of 800 or less, and more preferably 500 or less.

  Typical solvents for the solution (resist ink) containing an epoxy oligomer include, for example, alcohol solvents such as methanol, ethanol, propanol, isopropanol, N, N-dimethylformamide, N, N-diethylformamide, N, N. Amide solvents such as dimethylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, ether solvents such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane Ketone solvents such as acetone, MEK (methyl ethyl ketone), 2-pentanone, 3-pentanone, and γ-butyrolactone, and aromatic hydrocarbon solvents such as toluene and xylene. Rukoto can. Among these, toluene is particularly preferable. These solvents may be used alone or in combination of several kinds. The concentration of the epoxy oligomer in the solution (resist ink) containing the epoxy oligomer is preferably 0.1 to 5% by weight, and more preferably 0.5 to 1% by weight.

  In addition to the solute and solvent, the resist ink may contain a polymer component such as polystyrene or acrylic resin for the purpose of adjusting the viscosity of the resist ink and the volatility of the solvent. Further, the viscosity of the resist ink is preferably about 0.2 to 5 cP from the viewpoint of maintaining the adhesion to the mold and the pattern accuracy when adhered to the metal ion-containing layer.

  Examples of the method for attaching the resist ink having the above configuration to the mold include, for example, a method in which the pattern shape surface of the mold is brought into contact with a porous body impregnated with the resist ink, or a method in which the pattern shape surface of the mold is immersed in the resist ink. A method of spraying resist ink onto the pattern shape surface of the mold, a method of transferring the resist ink coated on a smooth substrate with a thin film onto the pattern shape surface of the mold, and the like.

  Next, the resist ink is attached to the surface of the coating film by bringing the pattern shape surface of the mold with the resist ink into contact therewith to form a resist mask to which the pattern shape has been transferred. That is, a fine pattern is printed using resist ink. In printing, from the viewpoint of uniformly attaching the resist ink to the surface of the coating film, it is preferable to bring the pattern shape surface of the mold into contact with the surface of the coating film at a predetermined pressure, for example, about 100 to 1000 Pa. From the same point of view as described above, after printing the resist ink on the surface of the coating film, after volatilizing the solvent at room temperature, contact the mold so that the pattern does not shift, and re-attach the resist ink for printing. It is also preferable to repeat.

  The drying method for fixing the resist ink containing the terminal-modified silicone, silane coupling agent, or epoxy oligomer after printing is not particularly limited, and natural drying, spray drying with an air gun, drying with an oven, or the like is used. be able to. The drying conditions depend on the type of polar solvent, but are 10 to 150 ° C. for 5 seconds to 60 minutes, preferably 25 to 150 ° C. for 10 seconds to 30 minutes, more preferably 30 to 120 ° C. for 1 minute to 10 minutes. It is.

  As described above, in the method of forming a patterned resist mask using a mold, the resist pattern formed on the surface of the coating film is a portion of the metal covered with the resist mask in the next metal deposition layer forming step. In addition to the function of suppressing the deposition, it also has a function of fixing to the mask region (that is, the resin surface between the circuit wirings) and increasing the surface insulation resistance between the wirings. In addition, the resist mask constituents are chemically bonded to the resin in a partially impregnated state on the resin surface, so that they have heat resistance and are different from photosensitive resist materials commonly used in photolithography. The process of peeling in the process of can be omitted.

Step c) A step of reducing the metal ions in the coating film to deposit a metal in a region not covered with the resist mask on the surface layer portion of the coating film to form a metal deposition layer:
As the reduction treatment method, it is particularly advantageous to use a wet reduction method. The wet reduction method is a method of reducing metal ions in an exposed region that is not masked by a resist layer by immersing the coating film in a solution containing a reducing agent (reducing agent solution). In this wet reduction method, metal ions existing inside the coating film (for example, a deep layer portion deeper than the surface layer portion or a coating portion immediately below the resist layer) are reduced at that location and deposited as metal. This is an effective method capable of preferentially performing metal deposition at the surface layer portion of the coating film while suppressing. Further, in the wet reduction method, there is little unevenness of metal deposition, and a uniform metal deposition layer can be formed in a short time. Since the metal deposit layer obtained in this way is partially embedded in the surface layer portion of the coating film (polyimide precursor resin layer), high adhesion can be obtained.

  As the reducing agent, for example, boron compounds such as sodium borohydride, potassium borohydride, dimethylamine borane and the like are preferable. These boron compounds can be used in the form of a solution (reducing agent solution) of sodium hypophosphite, formalin, hydrazines, and the like. The concentration of the boron compound in the reducing agent solution is preferably in the range of 0.005 to 0.5 mol / L, for example, and more preferably in the range of 0.01 to 0.1 mol / L. When the concentration of the boron compound in the reducing agent solution is less than 0.005 mol / L, reduction of the metal ions contained in the metal ion-containing layer may be insufficient, and when the concentration exceeds 0.5 mol / L, Due to the action, the polyimide precursor resin may be dissolved.

  Further, in the wet reduction treatment, the region not masked by the resist layer is placed in a reducing agent solution having a temperature within the range of 10 to 90 ° C., preferably within the range of 50 to 70 ° C., preferably 20 seconds to 30 minutes. Is immersed for 30 seconds to 10 minutes, more preferably 1 minute to 5 minutes. By soaking, metal ions in the metal ion-containing layer are reduced by the action of the reducing agent, and the metal is deposited in the form of particles on the surface layer portion of the coating film. At the end point of the reduction, there is almost no metal ion in the polyimide precursor resin other than the exposed surface layer portion of the coating film (for example, the deep layer portion or the coating portion immediately below the resist layer). This is because the metal ions in the coating film move to the surface layer part of the unmasked region of the coating film as the metal deposits on the surface layer part, and the migrated metal ions move to the surface layer. This is considered to be due to reduction near the part and metal deposition. At the end point of the reduction, there is almost no metal ions remaining in the coating film, but even if metal ions remain in the coating film, the remaining metal ions can be removed by acid treatment described later. . The determination of the end point of the reduction can be confirmed, for example, by measuring the cross section of the coating film using an energy dispersive X-ray (EDX) analyzer and reading the atomic weight% of the remaining metal ions.

  In the present embodiment, in the metal deposition layer forming step, the metal deposition layer that becomes the seed layer of the circuit wiring is formed only on a portion that is not covered with the patterned resist mask, and is not formed below the resist mask. Therefore, a flash etching process for finally removing the seed layer is unnecessary, and the number of processes can be reduced and the reliability of the circuit wiring board can be improved.

Step d) Step of forming a circuit wiring having a pattern on the metal deposition layer by electroless plating and / or electroplating:
Electroless plating is performed by immersing the coating film on which the metal deposition layer is formed in an electroless plating solution (electroless plating step). By this electroless plating, an electroless plating layer is formed. This electroless plating layer becomes the core of electroplating performed later.

  As the electroless plating solution used in the electroless plating process, a neutral to weakly acidic hypophosphorous acid nickel plating solution or boron-based nickel plating solution is selected in consideration of the influence on the polyimide precursor resin. It is preferable. As a commercially available product of a hypophosphorous acid nickel plating solution, for example, Top Nicolon (trade name; manufactured by Okuno Pharmaceutical Co., Ltd.) can be mentioned. Examples of commercially available boron-based nickel plating solutions include Top Chemialoy B-1 (trade name; manufactured by Okuno Pharmaceutical Co., Ltd.) and Top Chemialoy 66 (trade name; manufactured by Okuno Pharmaceutical Industries, Ltd.). Can do. Moreover, it is preferable to adjust the pH of the electroless plating solution to neutral to slightly acidic 4-7. In this case, for example, inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, boric acid, and carbonic acid, and organic acids such as acetic acid, glycolic acid, citric acid, and tartaric acid can be used. Furthermore, boric acid, carbonic acid, acetic acid, citric acid, and the like can be used. A weak acid such as an acid may be combined with these alkali salts to provide a buffering action. The temperature of the electroless plating treatment can be in the range of 80 to 95 ° C, and preferably in the range of 85 to 90 ° C. Moreover, the processing temperature of an electroless-plating process can be made into 20 second-10 minutes, Preferably it is 30 second-5 minutes, More preferably, it is 1 minute-3 minutes.

Next, electroplating is performed using the electroless plating layer as a core to form an electroplating layer (electroplating step). An electroplating layer is formed by electroplating so as to cover the electroless plating layer. Electroplating is, for example, plating having a composition containing sulfuric acid, copper sulfate, hydrochloric acid, and a brightener [for example, as a commercially available product, Macuspec (trade name) manufactured by Nihon McDermitt, Top Lucina SF (trade name) manufactured by Okuno Pharmaceutical Co., Ltd., etc.]. In the liquid, the electroless plating layer is used as a cathode, and a metal such as Cu is used as an anode. Current density in electroplating, for example, is preferably in the range of 0.2~3.5A / dm ^2. As the anode for electroplating, for example, metals such as Ni and Co can be used in addition to Cu. Moreover, chlorides, such as sodium chloride, can be added to a plating solution as needed.

  After the circuit wiring having the pattern is formed, the resist layer that has become unnecessary is peeled off. Although the method of peeling a resist layer is not ask | required, For example, the method of immersing in alkaline solutions, such as 1 to 4 weight% concentration sodium hydroxide aqueous solution and potassium hydroxide aqueous solution, etc. are preferable. At this time, the concentration of the alkaline solution is preferably 4% by weight or less in order to suppress deterioration of the polyimide modified layer due to the action of the alkaline solution. In addition, if the resist layer is peeled after imidization, the resist layer may be peeled off by the action of an alkaline solution for removing the resist. It is preferable to carry out before imidation of the resin. However, in the case where the resist layer is used as a part of the inter-circuit insulating layer of the circuit wiring, the resist layer is not required to be peeled off.

  Here, the removal of metal ions in the coating film will be described. In the wet reduction treatment, for example, when a metal salt such as sodium borohydride, potassium borohydride, dimethylamine borane, or the like is used, or when removing the resist layer, a metal salt such as sodium hydroxide or potassium hydroxide is used. In this case, since metal ions derived from the metal salt may be present in the coating film, it is preferable to remove them. The removal of metal ions is preferably performed by immersing in an aqueous solution of acid, and the applicable acid in this case dissociates the metal ions coordinated with the carboxyl groups of the polyamic acid. It is preferable to select a strong acid (acid dissociation constant pKa of 3.5 or less), and it is more preferable to select an acid that does not dissolve the metal deposited by reduction. Specific examples of such acids include citric acid (pKa = 2.87), oxalic acid (pKa = 1.04), and the like. Strong acids such as hydrochloric acid, nitric acid, and sulfuric acid may dissolve the metal deposition layer, and acetic acid (pKa = 4.56) is not preferable because the strength of the acid is low and it is difficult to remove metal ions. As conditions for the immersion treatment for removing metal ions, an aqueous acid solution having a concentration in the range of 1 to 15% by weight, preferably in the range of 5 to 10% by weight and in the range of 20 to 50 ° C., It is preferable to immerse in the range of 2 to 10 minutes. By performing such acid treatment, metal ions remaining in the coating film can be removed at the same time after the reduction is completed or after the resist layer is peeled off. The method for removing metal ions is also disclosed in, for example, “17th Microelectronics Symposium Proceedings”, September 2007, pages 179-182.

Step e) Step of forming an insulating resin layer obtained by imidizing the polyimide precursor resin in the coating film by heat treatment and laminating the sheet-like support member:
The imidization method is not particularly limited, and for example, heat treatment such as heating for 1 to 60 minutes under a temperature condition in the range of 80 to 400 ° C. is suitably employed. In order to suppress the oxidation of the circuit wiring, which is a metal layer formed by reduction and plating, heat treatment in a low oxygen atmosphere is preferable. Specifically, reduction of hydrogen or the like in an inert gas atmosphere such as nitrogen or a rare gas. It is preferably performed in a gas atmosphere or in a vacuum. Further, the step e is preferably performed after the step d, but may be performed before the step d. By passing through such a heat treatment, an insulating resin layer (single layer or plural polyimide resin layers) can be laminated on the sheet-like support member.

Step f) Step of separating the sheet-like support member from the insulating resin layer:
Step f is performed after step e. Thus, by completing the heat treatment with the sheet-like support member, it is possible to form a pattern without warping the insulating resin layer, and to improve the dimensional accuracy.

Step g) Step of forming an insulating film by thermocompression bonding of the coverlay film above the wiring:
The step g is preferably performed after the step e and before the step f.
The coverlay film functions as a protective resin layer for protecting the wiring. The coverlay film is laminated so as to cover the wiring by thermocompression bonding using an adhesive film of a thermosetting resin such as an epoxy resin or a polyimide resin processed into a predetermined shape according to the wiring pattern. Thermocompression bonding can be performed by a known hot pressing method. When the coverlay film is thermocompression-bonded, it is performed in a state equipped with a sheet-like support member, thereby suppressing the thermal shrinkage of the insulating resin layer and suppressing the dimensional change of the wiring formed in the insulating resin layer. The dimensional accuracy can be maintained.

  In the method of the present invention, the circuit wiring board is formed by performing the process f after the process e (and the process g) and separating the sheet-like support member and the insulating resin layer to form circuit wiring on the insulating resin layer. Can be produced. In addition, the circuit wiring board obtained in this way has a great effect of maintaining the dimensional accuracy of the wiring, particularly when the circuit wiring board is long. Therefore, it is preferable to carry out the roll-to-roll method until at least the step before the step of producing the circuit wiring board by peeling off the sheet-like support member and the insulating resin layer.

  In the above description, only the characteristic steps of the method of the present invention have been described. That is, when a circuit wiring board is manufactured, processes other than those normally performed, for example, processes such as through-hole processing in the previous process, terminal plating in the subsequent process, and external processing can be performed according to a conventional method.

  The method for manufacturing a circuit wiring board of the present invention preferably further includes a step h after the step a.

Step h) Step of increasing the content of metal ions in the coating film by impregnating the coating film with an aqueous solution containing metal ions and drying:
By this impregnation treatment, a free carboxyl group present in the coating film, that is, a carboxyl group that does not form a salt with a metal derived from a metal compound can be converted into a metal salt.

  As the metal ions used in the step h (metal ion impregnation step), the same metal compounds as those contained in the coating liquid used in the step a (coating film forming step) can be used.

  In the metal ion solution used in the metal ion impregnation step, the metal compound is preferably contained within a range of 30 to 300 mM, and more preferably within a range of 50 to 100 mM. If the concentration of the metal compound is less than 30 mM, it takes too much time to impregnate the coating film with metal ions, and if it exceeds 300 mM, the surface of the coating film may be corroded (dissolved).

  In addition to the metal compound, the metal ion solution can contain components intended for pH adjustment such as a buffer solution.

  The impregnation method is not particularly limited as long as the metal ion solution can come into contact with the surface of the coating film, and a known method can be used. For example, a dipping method, a spray method, a brush coating method or a printing method can be used. The impregnation temperature may be 0 to 100 ° C., preferably 20 to 40 ° C. The impregnation time is preferably 1 minute to 5 hours, for example, and more preferably 5 minutes to 2 hours, when applying the dipping method. Even when the immersion time exceeds 5 hours, the degree of impregnation of the coating film with metal ions tends to be almost flat.

  After impregnation, the coated film is dried. The drying method is not particularly limited, and for example, natural drying, spray drying with an air gun, drying with an oven, or the like can be used. Drying conditions are 10 to 150 ° C. for 5 seconds to 60 minutes, preferably 25 to 150 ° C. for 10 seconds to 30 minutes, and more preferably 30 to 120 ° C. for 1 minute to 10 minutes.

  After step h, the resist pattern forming step in step b and the metal deposited layer forming step in step c are preferably performed. By providing step h, the amount of metal ions in the coating film that is the polyimide precursor resin layer (That is, the content of metal ions in the coating film) can be increased. As a result, the metal deposition layer obtained in step c can be formed into a film shape, so that the electroless plating step can be omitted. Since electroless plating has a problem that the management of the plating solution and the treatment of the waste solution are complicated, if the circuit wiring with excellent adhesion to the substrate can be formed without performing the electroless plating, the industry The target value is very large. From this point of view, it is particularly preferable to further increase the amount of metal ions in the coating film by performing a metal ion impregnation step in step h after forming the coating film in step a. In addition, after the step c (that is, before the step d), the metal ion solution is brought into contact with the exposed portion of the coating film not covered with the patterned resist mask to perform the metal ion impregnation step of the step h. Sometimes you can.

  The method for manufacturing a circuit wiring board of the present invention preferably further includes step i after step a.

Step i) Step of impregnating the coating film with an aqueous ammonia solution or an aqueous solution of a primary or secondary amine:
By impregnating with an aqueous ammonia solution or a primary or secondary amine aqueous solution (hereinafter also referred to as an amine aqueous solution), the amine in the amine aqueous solution is coordinated with the ligand of the metal ion chelate complex present in the coating film. Ligand substitution produces a metal ion amine complex. The amine complex thus formed is in a state where the ligand is easily liberated when the metal ion is reduced, and as a result, the reduction reaction of the metal ion is considered to occur uniformly in the surface layer portion of the coating film. The primary or secondary amine is not particularly limited as long as it is water-soluble, but is preferably an aliphatic amine. Specific examples of such aliphatic amines include ethanolamine, propanolamine, butanolamine, diethanolamine, dipropanolamine, ethylenediamine, diethylamine and the like. Of the aliphatic amines, alcohol amines such as ethanolamine, propanolamine, butanolamine, diethanolamine, and dipropanolamine are more preferable. Among these, ammonia that is easy to handle and excellent in economy is particularly preferable. As the aqueous amine solution, the concentration is used within the range of 1 to 30% by weight, preferably within the range of 10 to 30% by weight, and the liquid temperature is within the range of 1 to 80 ° C, preferably within the range of 10 to 50 ° C. It is preferable. The method for impregnating the aqueous amine solution is not particularly limited. For example, a dipping method, a spray method, or brushing can be applied. For example, when the immersion method is applied, it is effective to perform the treatment for 10 seconds to 2 hours, preferably 1 to 30 minutes. When the concentration or temperature of the aqueous amine solution is less than the above lower limit, ligand substitution tends to be insufficient, and when it exceeds the above upper limit, metal ions present in the coating film tend to be eluted.

  The impregnated coating film may be subjected to the next step as it is, or the impregnated coating film may be dried after impregnation.

  After the amine treatment step of step i, it is preferable to perform the resist pattern formation step of step b and the metal precipitation formation step of step c. By providing step i, the metal precipitation layer obtained in step c is formed into a film shape. Therefore, the electroless plating process can be omitted.

  In the case where it is desired to omit the electroless plating step by performing the above steps h and i, it is advantageous to set the thickness of the coating film to 3 μm or more (preferably 3 to 50 μm). By setting it as such thickness, a sufficient amount of metal ions can be contained in the coating film. In addition, although the metal ion impregnation process of the process h and the amine treatment process of the process i should just perform any one, it is also possible to implement both the process h and the process i. In this case, a dense film-like metal deposition layer can be formed, which is preferable. When performing both the process h and the process i, the order is not ask | required, but it is preferable to perform the process i after the process h.

Here, the effect | action of this invention is demonstrated, referring FIG. FIG. 1A shows a case where the polyimide precursor resin layer 3 is imidized (step f; heat treatment) with the sheet-like support member 1 attached, and FIG. 1B shows the sheet-like support member 1. The case where imidation of the polyimide precursor resin layer 3 was performed in the state which is not attached is shown. First, in the conventional method, as shown in FIG. 1B, the sheet-like support member 1 is peeled off before the wiring 7 is formed, so that the polyimide resin layer 3a is heated by imidation. Contractile stress (indicated by a black arrow in FIG. 1B) is applied. As a result, the dimension of the wiring 7 changes before and after imidization, and for example, the wiring interval becomes L ₁ > L ₂ , and the dimensional accuracy is lowered. The reduction in the dimensional accuracy of the wiring that occurs in this manner tends to become a problem as the wiring interval is narrow. In particular, as the fine pitch circuit having a narrow wiring interval (for example, within a range of 1 to 10 μm in the wiring interval), the dimensional accuracy is reduced, and the interference of electric signals between adjacent wirings is likely to occur. This is a major cause of reduced sex and yield.

In the method of the present invention, the wiring 7 is formed by the direct metallization method with the polyimide precursor resin layer 3 laminated on the sheet-like support member 1, and further imidization is performed as shown in FIG. 1 (a). After that, the sheet-like support member 1 is peeled off. Since shrinkage of the polyimide resin layer 3a by heating during imidation is suppressed by laminating the sheet-like support 1, the dimensional accuracy of the wire 7 before and after the imidization hardly changes, for example, the wiring distance L ₁ L ₂ is approximately the same length. Therefore, sufficiently high dimensional accuracy can be obtained in the formation of circuit wiring formed by photolithography with a wiring interval of 20 to 50 μm, preferably about 25 to 40 μm. Further, for example, by forming a finer fine pitch circuit having a wiring interval in the range of 1 to 10 μm, preferably in the range of 2 to 5 μm, which is formed by a microcontact printing technique using a mold having a pattern shape, by heating Since a change in the dimensions of the wiring is prevented, an even greater effect can be obtained.

  In addition, by adopting the casting method, the sheet-like support member 1 has a function as a support in the casting method, a function of reinforcing the polyimide resin layer 3a (or polyimide precursor resin layer 3), and dimensions of the wiring 7 By providing the function of maintaining accuracy, it is possible to reduce the number of parts used and the number of processes such as laminating and peeling.

  In FIG. 1, the imidization treatment has been described as an example, but the same effect can be obtained by attaching the sheet-like support member 1 even in the coverlay process in which the coverlay film is thermocompression bonded.

  Thus, in the method of the present invention, by performing the heat treatment step (imidization, coverlay processing) after the wiring formation in a state where the polyimide precursor resin layer 3 formed by the casting method is attached to the sheet-like support member 1. Therefore, it is possible to manufacture a circuit wiring board that prevents the dimensional accuracy of the wiring 7 from being lowered, has a fine fine pitch, has high dimensional accuracy, and has high adhesion reliability between the wiring 7 and the polyimide resin layer 3a.

EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited at all by these Examples. Unless otherwise specified in the examples of the present invention, various measurements and evaluations are as follows. Moreover, the symbol used for the Example has the following meaning.
m-TB: 2,2'-dimethyl-4,4'-diaminobiphenyl TPE-R: 1,3-bis (4-aminophenoxy) benzene DMAc: N, N-dimethylacetamide PMDA: pyromellitic dianhydride DANPG: 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane BTDA: 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride

[Measurement of dimensional change after heating]
The dimensional change rate was measured according to the following procedure. First, using a 300 mm square sample, a dry film resist is exposed and developed at 200 mm intervals to form a position measurement target. After measuring the dimensions before etching (normal state) in an atmosphere at a temperature of 23 ± 2 ° C. and a relative humidity of 50 ± 5%, the copper other than the target of the test piece is etched (liquid temperature: 40 ° C. or less, within 10 minutes) Remove with. After being left for 24 ± 4 hours in an atmosphere having a temperature of 23 ± 2 ° C. and a relative humidity of 50 ± 5%, the dimension after etching is measured. Thereby, the distance between the initial position targets can be obtained.

  Next, this test piece is heat-treated in an oven at 250 ° C. for 1 hour, and the distance between the position targets thereafter is measured. The dimensional change rate with respect to the normal state at each of the three locations in the vertical direction and the horizontal direction is calculated, and the average value of each is taken as the dimensional change rate after the heat treatment. The heating dimensional change rate was calculated by the following mathematical formula.

Heating dimensional change rate (%) = (B−A) / A × 100
A: Distance between targets after wiring formation B: Distance between targets after heating

[Measurement of linear thermal expansion coefficient]
The linear thermal expansion coefficient was measured using a thermomechanical analyzer (manufactured by Seiko Instruments Inc.) at a rate of 20 ° C./minute up to 255 ° C., held at that temperature for 10 minutes, and then further 5 ° C./minute. Cooled at a constant rate. The average thermal expansion coefficient (linear thermal expansion coefficient) from 240 ° C. to 100 ° C. during cooling was calculated.

[Evaluation of adhesion]
Evaluation of adhesion is made by preparing a test piece for measuring circuit wiring having a width of 3 mm, and measuring the peel strength in a 90 ° direction at room temperature using a strograph-M1 (manufactured by Toyo Seiki Seisakusho). evaluated. In the evaluation of adhesion, the case where the peel strength is 0.5 kN / m or more and less than 1.0 kN / m is regarded as “no problem in practical use”, and the case where the peel strength is 1.0 kN / m or more is “ Excellent. "

[Evaluation method of warpage]
The conductor layer forming resin film is cut by a cutting machine to create a sheet of 10 cm × 10 cm size, and when the sheet is placed on the desk, the height from the desk surface of the part that is the most lifted from the desk surface is set. Measured using calipers. The height was defined as the amount of warpage of the conductor layer-forming resin film.

[Measurement of sheet resistance of metal layer]
The sheet resistance of the metal layer was measured by a method based on JIS K 7194 using a resistivity meter (MCP-T610 manufactured by Mitsubishi Chemical Corporation). In addition, when the measured value of the sheet resistance of the metal layer exceeds 50Ω / □ (ohm / square), the level is “difficult to electroplate”, and when it is 50Ω / □ or less, the level is “electroplatable”. It was evaluated. Moreover, when it was 30 Ω / □ or less, the metal layer was evaluated as “particularly excellent” as a conductive film.

Production Example 1
In a 500 ml separable flask, 15.77 g m-TB (0.074 mol) and 2.41 g TPE-R (0.008 mol) were dissolved in 264 g DMAc with stirring. Next, 17.82 g of PMDA (0.082 mol) was added to the solution under a nitrogen stream. Thereafter, the polymerization reaction was continued by stirring for 4 hours to obtain a viscous non-thermoplastic polyimide resin precursor resin solution a.

Production Example 2
In a 500 ml separable flask, 30.3 g DANPG (0.1 mol) was dissolved in 352 g DMAc with stirring. Next, 9.3 g PMDA (0.04 mol) and 20.5 g BTDA (0.06 mol) were added to the solution in a nitrogen stream. Thereafter, stirring was continued for about 3 hours to conduct a polymerization reaction, thereby obtaining a precursor resin solution b of a viscous thermoplastic polyimide resin.

Production Example 3
To the precursor resin solution b prepared in Preparation Example 2, 7.91 g of pyridine (0.1 mol) was added and stirred for 20 minutes. To this mixture, a solution of 22.0 g (0.08 mol) of commercially available nickel (II) acetylacetonate dihydrate dissolved in 160 ml of N-methyl-2-pyrrolidinone (hereinafter abbreviated as NMP) was added. The blue polyimide precursor nickel complex solution c was produced by stirring at room temperature for 1 hour.

Example 1
As a sheet-like support member, the thickness after imidization is 25 μm on a long copper foil 1 (HL foil manufactured by Nippon Electrolytic Co., Ltd., Rz 1.2 μm on the peel surface, contact angle 90 ° with water, thickness 18 μm) Then, the precursor resin solution a was applied and dried at 130 ° C. for 20 minutes. Further thereon, a polyimide precursor nickel complex solution c was applied so that the thickness after imidization was 2.5 μm, and dried at 130 ° C. for 20 minutes to form a polyimide precursor resin layer A1.

  On the surface of the resin layer A1, a dry film resist (manufactured by Asahi Kasei Co., Ltd., trade name: Sunfort AQ, thickness 10 μm) is laminated at 110 ° C., exposed to ultraviolet rays through a photomask, and 0.5% by weight. The polyimide precursor resin layer B1 having a mask pattern of 50 μm {wiring width / wiring spacing (L / S) = 20 μm / 30 μm} was obtained by developing with an aqueous sodium carbonate solution.

The resin layer B1 is immersed in a 10 mM aqueous solution of sodium borohydride (30 ° C.) for 2 minutes to form a nickel precipitation layer on the surface of the impregnation layer not masked with the resist layer. Obtained. In addition, when a cross-sectional observation of the surface layer portion of the nickel-deposited resin layer C1 was performed, nickel particles having an average particle diameter of about 50 nm were densely present from the outermost surface of the nickel-deposited resin layer C1 to a depth of about 100 nm (nickel It was confirmed that the particles were embedded. Next, this nickel-deposited resin layer C1 is immersed in an electroless nickel plating bath (Okuno Pharmaceutical Co., Ltd., trade name: Top Nicolon TOM-S) at 80 ° C. for 30 seconds, thereby providing a base for electrolytic copper plating. A nickel layer was formed. Furthermore, the formed nickel layer is electroplated at a current density in the range of 0.5 A / dm ^{2 to} 3.5 A / dm ^{2 in} an electric copper plating bath to form a copper wiring having a copper film thickness of 12 μm. Thus, a copper wiring forming resin layer D1 was obtained.

The imidization was completed by heating the resin layer D1 to 360 ° C. over about 15 minutes in a nitrogen atmosphere. Thereafter, it is cooled to room temperature under a nitrogen atmosphere, immersed in a 2% by weight sodium hydroxide aqueous solution (25 ° C.) for 3 minutes to remove the resist pattern, and then in a 10% by weight oxalic acid aqueous solution (25 ° C.) for 2 minutes. By dipping, residual metal ions were removed, washed with ion-exchanged water, and then dried to obtain a circuit wiring board E1 with a sheet-like support member. After heat-treating this circuit wiring board E1 in vacuum at 250 ° C. for 1 hour, the circuit wiring board E1 was peeled from the sheet-like support member to obtain a circuit wiring board E1 ′. The obtained circuit wiring board E1 ′ had no warpage, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer (polyimide resin layer) of the circuit wiring board E1 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm). Moreover, the heating dimensional change rate was -0.001%.

  A coverlay film (manufactured by Nikkan Kogyo Co., Ltd., trade name: Nikaflex, base film thickness 25 μm, adhesive layer thickness 25 μm) is attached to the wiring side surface of the above-described circuit wiring board E1 with a sheet-like support member, and 160 ° C. After obtaining a circuit wiring board F1 with a sheet-like support member in which a coverlay film was laminated by a 1-hour heating press, the sheet-like support member was peeled off to obtain a circuit wiring board F1 ′ with a coverlay film. It was -0.002% when the heating dimensional change rate was measured by the method similar to the said method.

Example 2
In the same manner as in Example 1, a polyimide precursor resin layer A2 composed of a non-thermoplastic polyimide resin precursor resin layer and a polyimide precursor nickel complex resin layer was formed on the sheet-like support member. The resin layer A2 was immersed in a 100 mM nickel acetate aqueous solution (25 ° C.) for 10 minutes, and the resin layer A2 was impregnated with nickel ions to form a polyimide precursor resin layer A2 ′.

In Example 1, a polyimide precursor resin layer B2 having a mask pattern formed in the same manner as in Example 1 except that polyimide precursor resin layer A2 ′ was used instead of polyimide precursor resin layer A1. Nickel-deposited resin layer C2 was formed. The sheet resistance of the nickel deposition layer in the resin layer C2 was 25Ω / □, and was particularly excellent as a metal film. The nickel-deposited resin layer C2 is electroplated at an electric current density in the range of 0.5 A / dm ^{2 to} 3.5 A / dm ^{2 in} an electric copper plating bath to form a copper wiring having a copper film thickness of 12 μm. Then, a copper wiring forming resin layer D2 was obtained, and a circuit wiring board E2 with a sheet-like supporting member and a circuit wiring board E2 ′ from which the sheet-like supporting member was peeled were produced in the same manner as in Example 1. The obtained circuit wiring board E2 ′ had no warp, the copper wiring peel strength was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E2 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E2 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F2 'with a coverlay film.

Example 3
In the same manner as in Example 1, a polyimide precursor resin layer A3 composed of a non-thermoplastic polyimide resin precursor resin layer and a polyimide precursor nickel complex resin layer was formed on the sheet-like support member. This resin layer A3 was immersed in a 25 wt% aqueous ammonia solution (25 ° C.) for 2 minutes, then washed with water and dried to form a polyimide precursor resin layer A3 ′.

In Example 1, polyimide precursor resin layer B3 on which a mask pattern was formed in the same manner as in Example 1 except that polyimide precursor resin layer A3 ′ was used instead of polyimide precursor resin layer A1. Nickel-deposited resin layer C3 was formed. The sheet resistance of the nickel deposition layer in the resin layer C3 was 42Ω / □, and a metal film capable of direct electroplating was formed. The nickel-deposited resin layer C3 is electroplated at a current density in the range of 0.5 A / dm ^{2 to} 3.5 A / dm ^{2 in} an electric copper plating bath to form a copper wiring having a copper film thickness of 12 μm. Then, a copper wiring forming resin layer D3 was obtained, and a circuit wiring board E3 with a sheet-like supporting member and a circuit wiring board E3 ′ from which the sheet-like supporting member was peeled were produced in the same manner as in Example 1. Further, the obtained circuit wiring board E3 ′ had no warp, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E3 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E3 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F3 'with a coverlay film.

Example 4
In Example 3, instead of being immersed in a 25 wt% aqueous ammonia solution (25 ° C) for 2 minutes, it was the same method as in Example 3 except that it was immersed in an aqueous 25 wt% ethanolamine solution (25 ° C) for 2 minutes. A circuit wiring board E4 having a sheet-like support member and a circuit wiring board E4 having a sheet-like support member peeled off after forming a polyimide precursor resin layer B4, a nickel deposition resin layer C4 and a copper wiring-forming resin layer D4 on which a mask pattern is formed. 'Made. The sheet resistance of the nickel deposition layer in the nickel deposition resin layer C4 was 45Ω / □, and a metal film capable of direct electroplating was formed. In addition, the obtained circuit wiring board E4 ′ had no warpage, the copper wiring peel strength was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E4 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E4 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F4 'with a coverlay film.

Example 5
In Example 1, the precursor resin solution a was applied so that the thickness after imidization was 25 μm, and the polyimide precursor nickel complex solution c was applied so that the thickness after imidization was 2.5 μm. Instead of applying the precursor resin solution a so that the thickness after imidization is 5 μm and applying the polyimide precursor nickel complex solution c so that the thickness after imidization is 1.4 μm. In the same manner as in Example 1, a polyimide precursor resin layer A5, a polyimide precursor resin layer B5 on which a mask pattern is formed, a nickel-deposited resin layer C5, and a copper wiring forming resin layer D5 are formed, and a sheet-like support is formed. A circuit wiring board E5 ′ from which the circuit wiring board with members E5 and the sheet-like supporting member were peeled was produced. The obtained circuit wiring board E5 ′ had no warp, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E5 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E5 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F5 'with a coverlay film.

Example 6
As a sheet-like support member, a non-thermoplastic polyimide resin precursor resin solution a is applied onto a long copper foil 1, dried at 130 ° C. for 20 minutes, and then heated to 360 ° C. over about 15 minutes. Then, a polyimide resin layer having a thickness of 25 μm was formed, and a polyimide resin layer supported by a sheet-like support member was produced. The surface of the polyimide resin layer was subjected to plasma treatment for 25 seconds under an inert gas atmosphere of argon and helium with an applied voltage of 5 kV and a frequency of 10 kHz and a power of 250 W, and then the thickness after imidization was 2 The polyimide precursor nickel complex solution c was applied to a thickness of 0.5 μm and dried at 130 ° C. for 20 minutes to form a polyimide precursor resin layer A6.

In Example 1, instead of the polyimide precursor resin layer A1, a polyimide precursor resin layer B6 on which a mask pattern was formed, nickel, in the same manner as in Example 1, except that the polyimide precursor resin layer A6 was used. Precipitation resin layer C6 and copper wiring formation resin layer D6 were formed, and circuit wiring board E6 with a sheet-like support member and circuit wiring board E6 'which peeled off the sheet-like support member were produced. The obtained circuit wiring board E6 ′ had no warpage, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E6 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E6 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F6 'with a coverlay film.

Example 7
In the same manner as in Example 1, a polyimide precursor resin layer A7 including a non-thermoplastic polyimide resin precursor resin layer and a polyimide precursor nickel complex resin layer was formed on the sheet-like support member. The resin layer A7 was immersed in a 25 wt% aqueous ammonia solution (25 ° C.) for 2 minutes, then washed with water and dried to form a polyimide precursor resin layer A7 ′.

  PDMS (commonly known as silicone rubber) is added to a membrane filter (nitrocellulose membrane filter, pore size 0.22 μm, manufactured by MILLIPORE) impregnated with 1% toluene solution of diaminopropyl-polydimethylsiloxane (KF8010 manufactured by Shin-Etsu Chemical Co., Ltd.) Ink adheres to the surface of the concavo-convex pattern by stamping the manufactured concavo-convex pattern (depth of the recess; 5 μm, pattern shape; wiring width / wiring interval (L / S) = 5 μm / 5 μm, pattern area: 1 square cm) I let you. After drying the concavo-convex pattern with the ink attached for 1 minute (room temperature 23 ° C., humidity 50%), the ink on the concavo-convex pattern surface of the resin layer A7 ′ is stamped again on the surface of the polyimide precursor resin layer A7 ′. It was transferred to the surface and subsequently heat treated at 130 ° C. for 5 minutes to form a polyimide precursor resin layer B7 having a mask pattern formed on the surface of the resin layer A7 ′.

The resin layer B7 was treated in the same manner as in Example 1 to form a nickel deposited resin layer C7. The sheet resistance of the nickel deposition layer in the resin layer C7 was 42Ω / □, and a metal film capable of direct electroplating was formed. The nickel-deposited resin layer C7 is electroplated at a current density of 0.5 A / dm ^{2 in} an electric copper plating bath to form a copper wiring having a copper film thickness of 3 μm. Obtained. The obtained resin layer D7 is heated to 360 ° C. in a nitrogen atmosphere for about 15 minutes to complete imidization, and then cooled to room temperature in a nitrogen atmosphere to provide a circuit wiring board E7 with a sheet-like support member. Got. After heat-treating this circuit wiring board E7 in vacuum at 250 ° C. for 1 hour, the circuit wiring board E7 was peeled from the sheet-like support member to obtain a circuit wiring board E7 ′. The obtained circuit wiring board E7 ′ had no warp, the peel strength of the copper wiring was 1.1 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E7 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E7 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F7 'with a coverlay film.

Example 8
In Example 7, instead of using a 1% toluene solution of diaminopropyl-polydimethylsiloxane, a 1% by weight toluene solution of aminopropyl-triethoxysilane (KBE-903 manufactured by Shin-Etsu Chemical Co., Ltd.) was used. In the same manner as in Example 7, a nickel-deposited resin layer C8 was formed, and a circuit wiring board E8 with a sheet-like support member and a circuit wiring board E8 ′ from which the sheet-like support member was peeled were produced. The obtained circuit wiring board E8 ′ was not warped, the copper wiring was peeled off at 1.1 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E8 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E8 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F8 'with a coverlay film.

Example 9
Example 7 was the same as Example 7 except that a 1% by weight toluene solution of an epoxy oligomer (ZX-1059 manufactured by Toto Kasei Co., Ltd.) was used instead of the 1% toluene solution of diaminopropyl-polydimethylsiloxane. In this way, a nickel-deposited resin layer C9, a circuit wiring board E9 with a sheet-like support member, and a circuit wiring board E9 ′ from which the sheet-like support member was peeled were produced. The obtained circuit wiring board E9 ′ was not warped, the copper wiring was peeled off at 1.1 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E9 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E9 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F9 'with a coverlay film.

Example 10
In the same manner as in Example 1, a polyimide precursor resin layer A10 composed of a non-thermoplastic polyimide resin precursor resin layer and a polyimide precursor nickel complex resin layer was prepared on a sheet-like support member.

  PDMS (commonly known as silicone rubber) is added to a membrane filter (nitrocellulose membrane filter, pore size 0.22 μm, manufactured by MILLIPORE) impregnated with 1% toluene solution of diaminopropyl-polydimethylsiloxane (KF8010 manufactured by Shin-Etsu Chemical Co., Ltd.) Ink adheres to the surface of the concavo-convex pattern by stamping the manufactured concavo-convex pattern (recess depth: 2 μm, pattern shape; wiring width / interval (L / S) = 2 μm / 2 μm, pattern area: 1 square cm) I let you. After drying the concavo-convex pattern with the ink attached for 1 minute (room temperature 23 ° C., humidity 50%), the ink on the concavo-convex pattern surface is applied to the surface of the resin layer A10 by stamping again on the surface of the polyimide precursor resin layer A10. Subsequently, heat treatment was performed at 130 ° C. for 5 minutes to obtain a polyimide precursor resin layer B10 ′ in which a mask pattern was formed on the surface of the resin layer A10.

  Next, the resin layer B10 ′ is immersed in a mixed aqueous solution (25 ° C.) of 100 mM nickel acetate-600 mM ammonia for 10 minutes to form a resist pattern, and a polyimide precursor resin layer B10 ″ impregnated with nickel ions. Produced.

The resin layer B10 ″ was treated in the same manner as in Example 1 to form a nickel-deposited resin layer C10. The sheet resistance of the nickel-deposited layer in the resin layer C10 was measured and found to be 25Ω / □, A metal film capable of being plated was formed, and this nickel-deposited resin layer C10 was electroplated in an electric copper plating bath at a current density of 0.5 A / dm ² to form a copper wiring with a copper film thickness of 3 μm. After the imidization was completed by heating the obtained resin layer D10 to 360 ° C. over about 15 minutes in a nitrogen atmosphere, the resin layer D10 was obtained in a nitrogen atmosphere. After cooling to room temperature, a circuit wiring board E10 with a sheet-like support member was obtained, which was heat-treated in vacuum at 250 ° C. for 1 hour, and then from the sheet-like support member to the circuit wiring board E1. The circuit wiring board E10 ′ obtained was peeled off, and the obtained circuit wiring board E10 ′ had no warp and had a copper wiring peeling strength of 1.3 kN / m. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E10 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%. It was.

  In the same manner as in Example 1, after the coverlay film was laminated on the circuit wiring board E10 with a sheet-like support member, the sheet-like member was peeled off to obtain a circuit wiring board F10 'with a coverlay film.

Example 11
In Example 10, instead of using a 1% toluene solution of diaminopropyl-polydimethylsiloxane, a 1% by weight toluene solution of aminopropyl-triethoxysilane (KBE-903 manufactured by Shin-Etsu Chemical Co., Ltd.) was used. In the same manner as in Example 10, a nickel-deposited resin layer C11 was formed, and a circuit wiring board E11 with a sheet-like support member and a circuit wiring board E11 ′ from which the sheet-like support member was peeled were produced. The obtained circuit wiring board E11 ′ had no warp, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E11 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E11 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F11 'with a coverlay film.

Example 12
Example 10 was the same as Example 10 except that a 1% by weight toluene solution of an epoxy oligomer (ZX-1059 manufactured by Toto Kasei Co., Ltd.) was used instead of the 1% toluene solution of diaminopropyl-polydimethylsiloxane. In this way, a nickel-deposited resin layer C12, a circuit wiring board E12 with a sheet-like support member, and a circuit wiring board E12 ′ from which the sheet-like support member was peeled were produced. The obtained circuit wiring board E12 ′ had no warp, the peel strength of the copper wiring was 1.3 kN / m, and was excellent in adhesion between the insulating resin layer and the wiring. The linear thermal expansion coefficient of the insulating resin layer of this circuit wiring board E12 ′ was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.001%.

  In the same manner as in Example 1, a coverlay film was laminated on the circuit wiring board E12 with a sheet-like support member, and then the sheet-like member was peeled off to obtain a circuit wiring board F12 'with a coverlay film.

  The outline and test results of the tests of Examples 1 to 12 are summarized in Table 1.

Comparative Example 1
On the copper foil 1, the precursor resin solution a was apply | coated so that the thickness after imidation might be set to 25 micrometers, and it dried at 130 degreeC for 20 minutes. Furthermore, after the precursor resin solution b was applied so that the thickness after imidization was 2.5 μm and dried at 130 ° C. for 20 minutes to form a polyimide precursor resin layer, under a nitrogen atmosphere The polyimide resin layer laminated | stacked on copper foil was formed by heating to 360 degreeC over about 15 minutes. This polyimide resin layer was peeled from the copper foil to obtain a roll-shaped polyimide film. Plasma was generated on the surface of the thermoplastic polyimide resin layer side of this film with a long sputtering apparatus in a tank pressure of 3 × 10 ⁻⁴ Pa and an argon gas atmosphere, and a nickel: chromium alloy layer [ratio 8: 2 , 99.9% by weight, hereinafter, a nichrome layer] was formed on the polyimide layer so as to be a thin film having a thickness of 30 nm. A copper film (99.99% by weight) was further formed on the nichrome layer by sputtering to a thickness of 0.2 μm to form a sputtering film. On this sputtering film, a copper layer having a thickness of 12 μm was further formed by electrolytic copper plating to form a circuit forming substrate having a conductor layer. Next, the conductor layer of the circuit forming substrate was etched with a ferric chloride solution to form a comb pattern having a pitch of 50 μm and a conductor portion for a position target, thereby obtaining a circuit wiring substrate. The substrate was heat-treated in vacuum at 250 ° C. for 1 hour, and then the polyimide layer with the conductor portion for the position target was peeled from the sheet-like support member, and the heating dimensional change rate was measured. The linear thermal expansion coefficient of the insulating resin layer was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.005%.

Comparative Example 2
In Example 1, a circuit wiring board was prepared in the same manner as in Example 1 except that a commercially available polyimide film, Upilex S (registered trademark; manufactured by Ube Industries, Ltd., thickness 50 μm) was used as the sheet-like support member. Obtained. The coefficient of linear thermal expansion of the insulating resin layer of this circuit wiring board was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.04%.

Comparative Example 3
Without using a sheet-like support member, a conductor layer having a thickness of 12 μm was formed on Kapton EN (trade name; manufactured by Toray DuPont Co., Ltd., thickness: 38 μm) as a commercially available polyimide film by sputtering and electrolytic copper plating. Next, the circuit wiring board was obtained by etching the conductor layer so that the conductor portion for the position target remained. This substrate was heat-treated in vacuum at 250 ° C. for 1 hour, and the linear thermal expansion coefficient and the heating dimensional change rate of the polyimide resin layer were measured. The linear thermal expansion coefficient of the polyimide resin layer was 23 × 10 ⁻⁶ / K (= 23 ppm), and the heating dimensional change rate was −0.05%.

Comparative Example 4
50 polyimide film (manufactured by Toray DuPont, trade name: Kapton EN, 100 mm × 100 mm × 25 μm thickness, linear thermal expansion coefficient (CTE) 16 × 10 ⁻⁶ / K) in 5N potassium hydroxide aqueous solution Immersion at 10 ° C. for 10 minutes. Thereafter, the immersed polyimide film is sufficiently washed with ion-exchanged water, immersed in a 1% by weight hydrochloric acid aqueous solution (25 ° C.) for 30 seconds, further sufficiently washed with ion-exchanged water, and dried by blowing compressed air. Thus, a surface-treated polyimide film was obtained.

  Next, the surface-treated polyimide film was immersed in a 100 mM nickel acetate aqueous solution (25 ° C.) for 10 minutes, and the impregnated layer (metal ion-containing layer) was formed by impregnating the alkali-treated layer with nickel ions. Thereafter, a dry film resist (manufactured by Asahi Kasei Co., Ltd., trade name: Sunfort AQ, 10 μm thickness) is laminated on the surface of the impregnated layer at a temperature of 110 ° C., exposed to ultraviolet rays through a photomask, and 0.5% by weight. The film was developed with an aqueous sodium carbonate solution to form a resist pattern of 50 μm {wiring width / wiring interval (L / S) = 20 μm / 30 μm} to obtain a film on which the resist pattern was formed.

The film was immersed in a 10 mM aqueous solution of sodium borohydride (30 ° C.) for 2 minutes to form a nickel deposition layer on the surface of the impregnation layer in a region not masked with the resist layer, thereby obtaining a nickel deposition film. It was 1500 ohms / square as a result of measuring the sheet resistance of this nickel deposit film. Next, this film is immersed in an electroless nickel plating bath (Okuno Pharmaceutical Co., Ltd., trade name: Top Nicolone TOM-S) at a temperature of 80 ° C. for 30 seconds, so that nickel as a base for electrolytic copper plating A layer was formed. Here, the sheet resistance of the nickel layer formed by electroless nickel plating was 15Ω / □. Further, the formed nickel layer was electroplated at an electric current density of 3.5 A / dm ^{2 in} an electric copper plating bath to form a copper wiring having a copper film thickness of 10 μm to obtain a copper wiring forming film. .

  The obtained copper wiring forming film was immersed in a 2% by weight sodium hydroxide aqueous solution (25 ° C.) for 3 minutes to peel off the resist pattern, and then immersed in a 10% by weight oxalic acid aqueous solution (25 ° C.) for 2 minutes. Thus, residual metal ions were removed.

  After the copper wiring forming film was washed with ion-exchanged water, imidization was completed by heating to 360 ° C. over about 15 minutes in a nitrogen atmosphere. Then, it cooled to normal temperature in nitrogen atmosphere, and obtained the copper wiring formation film. The peel strength of the copper wiring was 0.7 kN / m, and there was no problem in the adhesion between the insulating resin layer and the wiring, but the heating dimensional change rate was -0.05%.

  As shown in Table 1, in Examples 1 to 12 in which the process up to the imidization treatment was performed with the copper foil as the sheet-like support member attached, the heating dimensional change rate was -0.001%. In addition, the dimensional accuracy of the wiring pattern was maintained even after heat treatment for imidization. This dimensional accuracy could be substantially maintained even after the coverlay film was formed by thermocompression bonding (see Example 1). In particular, in Examples 2 to 4 and 7 to 12, by performing impregnation treatment with metal ions, ammonia treatment, ethanolamine treatment, etc., the sheet resistance of the nickel deposition layer becomes sufficiently small and excellent in electrical conductivity. It was possible to omit the plating step. Also, in Examples 7 to 12 in which wiring was formed with a width of 2 to 5 μm using a mold having an uneven pattern, it was possible to maintain the accuracy of wiring dimensions.

  On the other hand, the comparative example 1 which peeled the polyimide resin layer and the sheet-like support member before wiring formation, the comparative example 2 which used the synthetic resin as a sheet-like support member, and wiring formation were performed without using a sheet-like support member. In Comparative Example 3 and Comparative Example 4, the heating dimensional change rate was as large as -0.005% to -0.05%, and it was confirmed that the dimensional accuracy of the wiring pattern was greatly reduced.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made.

  DESCRIPTION OF SYMBOLS 1 ... Sheet-like support member, 3 ... Polyimide precursor resin layer, 3a ... Insulating resin layer (polyimide resin layer), 7 ... Wiring

Claims (5)

A method of manufacturing a circuit wiring board by forming circuit wiring on an insulating resin layer,
a) Containing a polyimide precursor resin and a metal compound directly on a metal sheet-like support member or on a polyimide resin layer or a polyimide precursor resin layer supported by a metal sheet-like support member A step of forming a coating film by applying and drying the coating liquid to be applied;
b) forming a patterned resist mask on the surface of the coating film;
c) Metal ions in the coating film are treated with a reducing agent solution containing a boron compound to reduce the metal ions , thereby precipitating metal in a region not covered with the resist mask in the surface layer portion of the coating film. Forming a deposited layer;
d) forming a circuit wiring having a pattern on the metal deposition layer by electroless plating and / or electroplating;
e) imidizing the polyimide precursor resin in the coating film by heat treatment to form an insulating resin layer laminated on the sheet-like support member;
f) separating the sheet-like support member from the insulating resin layer ; and
g) A step of forming an insulating film by performing thermocompression bonding of a coverlay film on the layer above the wiring after performing the step e and before the step f.
Bei to give a,
The sheet-like support member has a surface roughness Rz that is in contact with the insulating resin layer and is long and less than 1.4 μm, and the steps are performed by a roll-to-roll method. A method of manufacturing a circuit wiring board. In step b, formation of the resist mask includes
After the resist ink is attached to the pattern shape surface of the mold having the pattern shape, the resist ink is attached to the surface of the coating film by bringing the pattern shape surface of the mold with the resist ink into contact with the surface of the coating film. The method for manufacturing a circuit wiring board according to claim 1, wherein the method is performed. Method of manufacturing a circuit wiring board according to claim 1 or claim 2 wherein the sheet-like supporting member, characterized by using as the means for maintaining the dimensional accuracy of the wiring. And h) impregnating the coating film with an aqueous solution containing metal ions, followed by drying to increase the content of metal ions in the coating film. The manufacturing method of the circuit wiring board of any one of Claims 1-3 . After step a, further, i) any one of claim 4, wherein the step of the coating film is impregnated with an aqueous solution of aqueous ammonia or a primary or secondary amine, claim 1, characterized in that it comprises a The manufacturing method of the circuit wiring board as described in any one of.

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