JP6682190B2 - Insulator with metal coating, semiconductor device, and method for manufacturing insulator with metal coating - Google Patents

Description

  The present invention relates to an insulator with a metal coating, a semiconductor device having the insulator with a metal coating, and a method for manufacturing an insulator with a metal coating.

  In recent years, the frequency of transmission signals has been increasing in the semiconductor field. A cycloolefin polymer is known as a material having excellent dielectric properties (low dielectric constant (ε) and low dielectric loss tangent (tan δ)) in a high frequency region that can cope with the high frequency of the transmission signal.

  As a technique for forming a conductive film having good adhesion to the cycloolefin polymer, a cycloolefin polymer material with a metal film in which a metal thin film is formed on the surface of the surface-modified cycloolefin polymer material is disclosed ( Patent Document 1). The surface modification method applied to the surface of the cycloolefin polymer material includes a step of degreasing the surface of the cycloolefin polymer material, a step of irradiating the cycloolefin polymer material with ultraviolet rays in an aerobic atmosphere, and the resulting cycloolefin polymer material. Including a step of washing with water.

  However, since the cycloolefin polymer generally has a glass transition temperature (hereinafter, referred to as Tg) of about 120 ° C., there is a problem that it cannot meet the market demand for applications requiring high heat resistance. There is also a problem that the adhesive strength of copper plating is not sufficient.

JP, 2009-94923, A

  It is an object of the present invention to solve the above problems, that is, to provide an insulator with a metal coating, which has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating.

The present invention relates to an insulator with a metal coating, a semiconductor device, and a method for manufacturing an insulator with a metal coating, which solve the above problems by having the following configurations.
[1] A resin composition comprising (A) a resin and (B) a styrenic block copolymer in which an unsaturated double bond of a main chain in a molecule is hydrogenated, and having a glass transition temperature (Tg) of An insulator with a metal coating, comprising an insulator having a temperature of 150 ° C. or higher and a metal coating on at least one surface of the insulator.
[2] The insulator with a metal coating according to the above [1], wherein the insulator has a glass transition temperature (Tg) of 180 ° C. or higher.
[3] The insulator with a metal coating according to the above [1] or [2], wherein the insulator has an elastic modulus of 100 MPa to 2 GPa.
[4] The insulator with a metal coating according to any one of the above [1] to [3], wherein the surface roughness (Rzjis) of the insulator at the interface between the insulator and the metal coating is 1 μm or less.
[5] A semiconductor device having the insulator with a metal coating according to any one of [1] to [4] above.
[6] A resin composition comprising (I) (A) resin and (B) a styrene block copolymer in which an unsaturated double bond of the main chain in the molecule is hydrogenated, and having a glass transition temperature (Tg ) Forms an insulator having a temperature of 150 ° C. or higher,
(II) A step of performing electroless plating and electrolytic plating in this order on the formed insulator to form a metal film,
Are provided in this order, and a method for producing an insulator with a metal coating.

  According to the present invention [1], it is possible to provide an insulator with a metal coating, which has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating.

  According to the present invention [5], a highly reliable semiconductor device can be provided by an insulator with a metal coating, which has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating.

  According to the present invention [6], it is possible to produce an insulator with a metal coating, which has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating.

It is a figure which shows the transmission loss of the insulator with a metal film which concerns on this invention.

[Insulator with metal coating]
The insulator with a metal coating of the present invention (hereinafter referred to as the insulator with a metal coating) is a resin (A) and a styrene block copolymer in which an unsaturated double bond of a main chain in a molecule is hydrogenated. Which has a glass transition temperature (Tg) of 150 ° C. or higher, and a metal coating on at least one surface of the insulator. Here, the insulator is formed from the composition for insulator.

  The resin as the component (A) imparts high frequency characteristics, heat resistance and adhesiveness to the insulator. Here, the high frequency characteristic refers to a property of reducing transmission loss in a high frequency region of 10 GHz or more, a dielectric constant (ε) of 4 or less, and a dielectric loss tangent (tan δ) of 0.01 or less. Say. The component (A) is preferably a thermosetting resin, more preferably a thermosetting resin having a styrene group at the terminal, an epoxy resin or an imide resin, and further preferably a thermosetting resin having a styrene group at the terminal.

  As the thermosetting resin having a styrene group at the terminal, the following general formula (1):

(In the formula,
R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , and R ₇ may be the same or different and are a hydrogen atom, a halogen atom, an alkyl group, a halogenated alkyl group or a phenyl group,
— (O—X—O) — is represented by Structural Formula (2), wherein R ₈ , R ₉ , R ₁₀ , R ₁₄ and R ₁₅ may be the same or different and each is a halogen atom or a carbon number. An alkyl group having 6 or less or a phenyl group, R ₁₁ , R ₁₂ , and R ₁₃ may be the same or different and each is a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group;
-(Y-O)-is one kind of structure represented by Structural Formula (3) or two or more kinds of structures represented by Structural Formula (3) are randomly arranged, wherein R ₁₆ , R ₁₇ may be the same or different and is a halogen atom or an alkyl group having 6 or less carbon atoms or a phenyl group, R ₁₈ and R ₁₉ may be the same or different, and is a hydrogen atom, a halogen atom or a C 6 or less. An alkyl group or a phenyl group,
Z is an organic group having 1 or more carbon atoms, and may optionally contain an oxygen atom, a nitrogen atom, a sulfur atom, or a halogen atom,
a and b show the integer of 0-300 in which at least one is not 0,
C and d each represent an integer of 0 or 1), and a thermosetting polyphenylene ether oligomer having a phenyl group to which a vinyl group is bonded at both ends (hereinafter referred to as modified PPE) is preferable. When the modified PPE is used as the component (A), in addition to excellent high-frequency characteristics, it also has excellent heat resistance, so that the insulator does not easily change over time, and the long-term reliability of a semiconductor device having this insulator is high. You can maintain sex. Further, since the number of hydrophilic groups in the resin is small, it is excellent in hygroscopicity and chemical resistance. For this reason, the insulator does not peel off from the metal coating even in applications where a temperature of about 150 ° C. is required, and the semiconductor device has high reliability. In addition, the modified PPE has excellent insulating properties and can maintain the reliability of the semiconductor device even when the thickness of the insulator is reduced. This modified PPE is as described in JP-A-2004-59644.

Formula (1) shown by the modified PPE - (O-X-O ) - structural formula for the _{(2), R 8, R} 9, R 10, R 14, R 15 is preferably a carbon number It is an alkyl group having 3 or less, and R ₁₁ , R ₁₂ , and R ₁₃ are preferably hydrogen atoms or alkyl groups having 3 or less carbon atoms. Specifically, structural formula (4) can be given.

In Structural Formula (3) for — (YO) —, R ₁₆ and R ₁₇ are preferably alkyl groups having 3 or less carbon atoms, and R ₁₈ and R ₁₉ are preferably hydrogen atoms or carbon atoms. It is an alkyl group having a number of 3 or less. Specifically, structural formula (5) or (6) is mentioned.

  Z is an alkylene group having 3 or less carbon atoms, and is specifically a methylene group.

  a and b show the integer of 0-300 in which at least one is not 0, Preferably the integer of 0-30 is shown.

  The thermosetting resin having a styrene group at its terminal preferably has an average molecular weight of 800 to 3500, and more preferably 800 to 3000 of the modified PPE of the general formula (1). More preferably, the number average molecular weight is 800 to 2500. The number average molecular weight is a value using a calibration curve based on standard polystyrene by gel permeation chromatography (GPC).

  The epoxy resin is preferably a liquid epoxy resin from the viewpoint of reducing the melt viscosity of the composition. As the epoxy resin, aminophenol type epoxy resin, liquid bisphenol A type epoxy resin, liquid bisphenol F type epoxy resin, liquid naphthalene type epoxy resin, liquid hydrogenated bisphenol type epoxy resin, liquid alicyclic epoxy resin, liquid alcohol ether type Examples of the epoxy resin, liquid cycloaliphatic epoxy resin, liquid fluorene epoxy resin, liquid siloxane epoxy resin, and the like. From the viewpoint of fluidity and flexibility of the insulating composition, liquid bisphenol A epoxy resin, liquid Bisphenol F type epoxy resin and liquid naphthalene type epoxy resin are preferable. From the viewpoint of adhesiveness, heat resistance and durability, solid epoxy resin is preferable.

  The epoxy equivalent of the epoxy resin is preferably 80 to 300 g / eq from the viewpoint of viscosity adjustment. Commercially available epoxy resins include bisphenol A type epoxy resin manufactured by Daicel Chemical (product name: LX-01), aminophenol type epoxy resin manufactured by Mitsubishi Chemical (grade: JER630, JER630LSD), liquid epoxy resin manufactured by Mitsubishi Chemical (grade: 828). , 828EL), bisphenol A type epoxy resin manufactured by Nippon Steel Chemical (product name: YDF8170), bisphenol F type epoxy resin manufactured by Nippon Steel Chemical (product name: YDF870GS), naphthalene type epoxy resin manufactured by DIC (product name: HP4032D), made into Japan A medicinal biphenyl type epoxy resin (product name: NC-3000-H), a Shin-Etsu Chemical siloxane-based epoxy resin (product name: TSL9906) and the like can be mentioned.

  Examples of the imide resin include polyimide and maleimide compounds, and examples thereof include N-ethylmaleimide, N-cyclohexylmaleimide, N-isopropylmaleimide, N-methylmaleimide, N-butylmaleimide, 1,6-bismaleimide- (2, 2,4-trimethyl) hexane and the like.

  The imide resin is preferably a compound containing an N-phenylmaleimide skeleton. N- (o-hydroxyphenyl) maleimide, N- (m-hydroxyphenyl) maleimide, N- (p-hydroxyphenyl) maleimide, N- (p-nitrophenyl) maleimide, N-phenylmaleimide, N- (o- Methylphenyl) maleimide, N- (m-methylphenyl) maleimide, N- (p-methylphenyl) maleimide, N- (o-methoxyphenyl) maleimide, N- (m-methoxyphenyl) maleimide, N- (p- Methoxyphenyl) maleimide, N- (o-chlorophenyl) maleimide, N- (m-chlorophenyl) maleimide, N- (p-chlorophenyl) maleimide, N- (o-carboxyphenyl) maleimide, N- (p-carboxyphenyl) Maleimide, 4-methyl-1,3-phenylene bismaleimide, - it is a phenylene bismaleimide.

  The maleimidophenyl compound is preferably a compound containing at least two N-phenylmaleimide skeletons. For example, 4,4′-bismaleimide diphenylmethane, 4,4′-bismaleimide diphenyl ether, 4,4′-bismaleimide diphenyl sulfone, 1,3-bis- (3-maleimidophenoxy) benzene, 1,3-bis- (4-maleimidophenoxy) benzene, bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane, 2,2'-bis- [4- (4-maleimidophenoxy) phenyl] propane and the like.

  The component (A) may be used alone or in combination of two or more kinds.

  The component (B) is a styrene block copolymer in which an unsaturated double bond of the main chain in the molecule is hydrogenated, and this hydrogenated styrene block copolymer is a styrene-ethylene / butylene-styrene block copolymer. (SEBS), styrene- (ethylene-ethylene / propylene) -styrene block copolymer (SEEPS), styrene-ethylene / propylene-styrene block copolymer (SEPS), etc. are mentioned, and SEBS and SEEPS are preferable. This is because SEBS and SEEPS have good compatibility with polyphenylene ether (PPE), modified PPE, etc., which are options of the component (A), and can form an insulator having heat resistance. Further, since the styrene block copolymer contributes to lowering the elasticity of the insulator, it is suitable for applications where the insulator is required to have low elasticity of 2 GPa or less.

  The weight average molecular weight of the component (B) is preferably 30,000 to 200,000, and more preferably 80,000 to 120,000. The weight average molecular weight is a value using a calibration curve based on standard polystyrene by gel permeation chromatography (GPC).

  The component (B) may be used alone or in combination of two or more kinds.

  The component (A) is preferably 15 to 55 parts by mass with respect to 100 parts by mass of the insulator, from the viewpoint of high frequency characteristics, heat resistance and chemical resistance of the insulator.

  The component (B) is preferably 15 to 80 parts by mass with respect to 100 parts by mass of the insulator, from the viewpoints of plating adhesion, moldability of the insulating composition, and low melt viscosity.

  From the viewpoint of high frequency characteristics, heat resistance, and chemical resistance of the insulator, the insulator composition preferably contains polytetrafluoroethylene (PTFE) particles. The shape of the PTFE particles is preferably spherical and has an average particle diameter of 5 μm or less from the viewpoint of dispersibility in the insulator. The PTFE particles are preferably 0 to 65 parts by mass with respect to 100 parts by mass of the insulator.

  In addition, the composition for insulators is a filler other than PTFE, a coupling agent such as a silane coupling agent, a tackifier, a defoaming agent, a flow control agent, and a film formation aid, as long as the effect of the present invention is not impaired. Additives such as agents and dispersion aids may be included.

  The method for forming the insulator will be described below. The insulator is formed into a desired shape from the insulator composition.

  The composition for insulators can be prepared by dissolving or dispersing raw materials such as the components (A) and (B) constituting the resin composition in an organic solvent. The apparatus for dissolving or dispersing these raw materials is not particularly limited, but a Leika machine equipped with a stirring and heating device, a three-roll mill, a ball mill, a planetary mixer, a bead mill and the like can be used. . Further, these devices may be used in appropriate combination.

  Examples of the organic solvent include aromatic solvents such as toluene and xylene, and examples of ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. The organic solvent may be used alone or in combination of two or more kinds. The amount of the organic solvent used is not particularly limited, but it is preferably used so that the solid content is 15 to 50% by mass. From the viewpoint of workability, the composition for insulators preferably has a viscosity in the range of 200 to 3000 mPa · s. The viscosity is a value measured using an E-type viscometer at a rotation speed of 10 rpm and 25 ° C.

  As described above, the insulator is formed into a desired shape from the insulating composition. Specifically, the insulator can be obtained by applying the above-mentioned composition for an insulator onto a support, followed by drying or pouring it into a molding die. Hereinafter, a case will be described in which the composition for an insulator is applied on a support and then dried and cured to obtain a film of the insulator. The support is not particularly limited, and examples thereof include metal foils such as copper and aluminum, and organic films such as polyester resin, polyethylene resin, and polyethylene terephthalate resin (PET). The support may be release-treated with a silicone compound or the like. The shape of the insulator is not particularly limited, and examples thereof include a film, a plate, a block, and a line, and the film is preferable for high frequency applications.

  The method of applying the insulating composition to the support is not particularly limited, but from the viewpoint of thinning and controlling the film thickness, the gravure method, the slot die method, and the doctor blade method are preferable. By the slot die method, an uncured film of an insulating composition having a thickness after heat curing of 10 to 300 μm can be obtained. Here, the thickness of the uncured film of the insulating composition is preferably 10 to 300 μm from the viewpoint of high frequency characteristics and chemical resistance. The preferable thickness of the insulating film is the same as the preferable thickness of the uncured film of the insulating composition.

  The drying conditions can be appropriately set according to the type and amount of the organic solvent used in the insulating composition, the thickness of coating, and the like, and for example, at 50 to 120 ° C. for about 1 to 60 minutes. can do. The uncured film of the insulating composition thus obtained has good storage stability. The uncured film of the insulating composition can be peeled from the support at a desired timing.

  The uncured film of the insulating composition can be cured, for example, at 150 to 230 ° C. for 30 to 180 minutes. Curing of the uncured film of the insulator composition may be performed on the uncured film of the insulator composition alone, or after forming the metal coating described below.

  The glass transition temperature (Tg) of the insulator (for example, the cured insulator film) is 150 ° C. or higher, and preferably 180 ° C. or higher from the viewpoint of the heat resistance of the insulator. Here, the glass transition temperature (Tg) of the insulator is measured by "DMS6100" manufactured by SII Nanotechnology Inc.

  The elastic modulus of the insulator is preferably 100 MPa to 2.5 GPa from the viewpoint of application to a flexible wiring board. The pressure is more preferably 200 MPa to 2 GPa, further preferably 200 MPa to 1 GPa. Here, the elastic modulus of the insulator is measured at room temperature using an autograph.

  The metal coating on at least one surface of the insulator is formed by the method for producing an insulator with a metal coating described below.

  The surface roughness (Rzjis) of the insulator at the interface between the insulator and the metal coating is preferably 1 μm or less from the viewpoint of exhibiting performance in high frequency applications. If the surface of the insulator has irregularities of more than 1 μm, it is possible to improve the adhesion with the metal film by the physical anchor effect, but it is preferable that the surface of the insulator is smoother than 1 μm. The high-frequency characteristics are improved as compared with the insulator having irregularities of more than 1 μm on the surface. Here, the surface roughness (Rzjis) of the insulator is measured with a confocal microscope (Lasertec Co., Ltd., OPTELICS H1200) in an analysis range of 0.9 mm 2 and a 5-point average roughness.

  INDUSTRIAL APPLICABILITY The insulator with a metal coating of the present invention has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating, so that a highly reliable semiconductor device can be provided.

[Method for producing insulator with metal coating]
The method for producing an insulator with a metal coating of the present invention,
A resin composition comprising (I) (A) resin and (B) a styrene block copolymer in which an unsaturated double bond of the main chain in the molecule is hydrogenated, and having a glass transition temperature (Tg) of 150. A step of forming an insulator of ℃ or higher,
(II) A step of performing electroless plating and electrolytic plating in this order on the formed insulator to form a metal film,
In this order.

<(I) step>
The step (I) is as described above. The insulator here is an uncured product of the composition for insulator or a cured product of the composition for insulator. The glass transition temperature (Tg) in the case where the insulator is an uncured product of the insulating composition is the glass transition temperature (Tg) of the cured insulator.

<(II) step>
In the step (II), a metal thin film layer is formed on the insulator by electroless plating having excellent adhesion, and then electrolytic plating having excellent productivity is performed to form a metal film.

  Before performing electroless plating on the insulator, it is preferable to perform pretreatment in order to improve the adhesive strength between the insulator and the metal coating. As the pretreatment, ultraviolet (UV) irradiation treatment, cleaner treatment, catalyst treatment are preferable.

  When the insulator is irradiated with ultraviolet rays in the ultraviolet (UV) irradiation treatment, it is preferable to perform it in an oxygen-containing atmosphere. When UV irradiation is performed in an oxygen-containing atmosphere, the C—H bond on the surface of the insulator can be converted into —OH group and / or —C═O group by the irradiation UV energy to make it hydrophilic. Because it is considered. As the aerobic atmosphere, the atmosphere is preferable because it is the simplest. However, it is also possible to convert the structure into a structure in which N or the like is incorporated on the surface of the insulator, if it is carried out in an atmosphere containing an element capable of forming an organic polymer, such as a nitrogen atmosphere or an ammonia atmosphere.

Dominant wavelength of the ultraviolet to be used in this process, preferable to be 180Nm～400nm, UV intensity at the surface of the insulator is ^preferably a ^{1mW / cm 2 ~500mW / cm 2} . Here, when the wavelength of the ultraviolet rays is less than 180 nm, it does not mean that the modifying effect cannot be obtained, but is set as the lower limit of the wavelength that can be generally used. Therefore, it is considered that if there is a light source that can obtain a shorter wavelength, a more preferable effect can be obtained. On the other hand, when the wavelength of ultraviolet rays exceeds 400 nm, it is considered that the light transmittance of the insulator becomes large and it becomes difficult to obtain the modifying effect. A more preferable wavelength range of ultraviolet rays is 180 nm to 300 nm, and a further preferable wavelength range is 180 nm to 260 nm.

When the intensity of ultraviolet rays used is less than 1 mW / cm ^2, it takes a long time for reforming and the production efficiency is apt to deteriorate. On the other hand, when the intensity of ultraviolet rays is 500 mW / cm ² , the intensity of ultraviolet rays becomes too strong, and the deterioration of not only the surface but also the inside may occur, and the entire insulator tends to become brittle.

  The irradiation time of ultraviolet rays is preferably 5 seconds or more and less than 300 seconds, more preferably 15 seconds or more and less than 300 seconds, and further preferably 30 seconds or more and less than 300 seconds. If it is less than 5 seconds, the effect of ultraviolet irradiation may not be sufficient, and if it exceeds 300 seconds, the production efficiency tends to deteriorate.

Next, in the cleaner treatment, it is preferable to use an alkaline cleaner from the viewpoint of the effect of degreasing the oil and fat adhering to the insulator surface. For example, in the case of a film-shaped insulator, a release agent for the support used during coating is attached to the surface of the film-shaped insulator. For slight adhesion, degreasing treatment using an alkaline aqueous solution having a caustic soda concentration of about 50 g / dm ³ may be used. Alternatively, ultrasonic cleaning, plasma cleaning, or the like may be used. Even if the cleaner treatment is performed before the irradiation of ultraviolet rays, a sufficient effect may be obtained in some cases.

  For electroless plating, electroless copper plating, electroless nickel plating, or the like can be used. For use in high frequency applications, electroless copper plating that is not a magnetic metal is preferred. When electroless nickel plating is used, non-magnetic medium phosphorus type (P concentration in nickel plating film is 8 to 10% by mass), high phosphorus type (P concentration in nickel plating film is 11 to 13% by mass) %) Is preferred. Examples of the electroless copper plating bath include an electroless copper plating bath using formaldehyde as a reducing agent. The metal thin film layer formed by this electroless plating preferably has a thickness of 0.1 μm to 3 μm. If the thickness of the metal thin film layer is less than 0.1 μm, the uniformity of the film thickness tends to be impaired, and it becomes difficult to obtain a stable energized state during electrolytic plating. On the other hand, if the thickness of the metal thin film layer exceeds 3 μm, the cost will increase. Therefore, the thickness of the metal thin film layer is more preferably 0.5 μm to 2 μm.

  Examples of electrolytic plating include copper plating, nickel plating, tin plating, copper-zinc alloy plating, nickel-cobalt alloy plating, nickel-zinc alloy plating, and the like, and copper plating is preferable from the viewpoint of high-frequency characteristics and conductivity. Examples of the electrolytic copper plating bath include a copper sulfate bath, a copper cyanide bath, a copper pyrophosphate bath, and a copper borofluoride bath. From the viewpoint of productivity and cost, the copper sulfate bath is preferable.

  When an uncured product of the insulating composition is used as an insulator to be plated, it is cured after electrolytic plating.

  As described above, the metal-coated insulator can be obtained.

[Semiconductor device]
The semiconductor device of the present invention is highly reliable because it is formed by using the above-described insulator with a metal film, which has excellent high-frequency characteristics, excellent heat resistance, and high adhesion strength between the insulator and the metal film. Here, the semiconductor device refers to all devices that can function by utilizing semiconductor characteristics, and includes electronic parts, semiconductor circuits, modules incorporating these, electronic devices, and the like.

[Laminated board]
In addition, the insulator with a metal coating of the present invention is particularly applicable to a flexible copper clad laminate (FCCL) for a flexible printed circuit board (Flexible Printed Circuit, FPC) and a copper clad laminate for a multilayer board (FCCL). It is suitable for Copper Clad Laminate (CCL) or build-up material.

  The present invention will be described with reference to examples, but the present invention is not limited thereto. In the following examples, parts and% are parts by mass and% by mass, unless otherwise specified.

[Examples 1 to 7, Comparative Examples 1 to 3]
<Production of insulator film>
In the formulation shown in Table 7 , raw materials such as the components (A) and (B) and an appropriate amount of toluene as an organic solvent are metered and blended, and then these are put into a reaction kettle heated to 70 ° C. While rotating at 300 rpm, normal pressure mixing was performed for 3 hours to prepare a varnish containing the insulating composition.

  The varnish thus obtained was applied to one side of a support (a PET film that had been subjected to a mold release treatment) and dried at 100 ° C. to give an uncured film (thickness: 25 μm) of an insulator composition with a support. Obtained.

<Curing of uncured film of insulating composition>
Two 25 μm-thick uncured films were stuck together and heat-cured at 200 ° C. with the support attached to obtain a cured film having a thickness of 50 μm.

<Surface modification>
The surface modification treatment was performed under the conditions shown in Table 1.

<Formation of metal coating>
A copper coating was formed on the cured film that had been subjected to the surface modification treatment. Table 2 shows a flow of forming a metal coating by electroless copper plating and electrolytic copper plating, and Table 3 shows a flow of forming a metal coating by electroless copper nickel plating and electrolytic copper plating.

  Electroless plating is used to form the metal coating after the copper coating is formed, and two types are used: formalin bath (for copper thin film formation) and hypophosphorous acid bath (for copper nickel thin film formation). An electroless plated thin film of 0.2 to 0.3 μm was formed. Table 4 shows the bath composition and treatment conditions of the formalin bath, and Table 5 shows the bath composition and treatment conditions of the hypophosphorous acid bath.

On this copper thin film, a sulfuric acid copper plating solution having the composition shown in Table 6 was used to perform electrolysis at a solution temperature of 25 ° C. and a current density of 2 A / dm ² to form an electrolytic copper coating film having a thickness of 20 μm.

[Comparative Example 4]
Electrolytic copper foil (CF-T9FZ-SV-18 manufactured by Fukuda Metal Foil & Powder Co., Ltd.) was attached to the uncured film of the insulator composition with a support produced as described above by a press (200 ° C., 60 min, 10 kgf). After that, the film with a support was removed to prepare a test piece of Comparative Example 4. The test piece was cut into a width of 10 mm and peeled off with an autograph (Shimadzu Corporation ASG-J-5kNJ) to measure the peel strength. With respect to the measurement results, an average value of N = 5 was calculated.

[Evaluation of glass transition temperature (Tg)]
To confirm the heat resistance, the glass transition temperature (Tg) was measured using dynamic viscoelasticity measurement (DMA). Two uncured films having a thickness of 25 μm were stuck together and heat-cured at 200 ° C. for 60 minutes with the support attached to obtain a cured film having a thickness of 50 μm. After peeling this cured film from the support, a test piece (10 ± 0.5 mm × 40 ± 1 mm) was cut out from the cured film, and the width and thickness of the test piece were measured. Then, the measurement was performed using DMS6100 manufactured by SII Nano Technology Inc. (temperature rising rate: 3 ° C./min, measurement range: 25 to 220 ° C.). The peak temperature of tan δ was read and set as Tg. The results are shown in Table 7.

[Evaluation of elastic modulus]
Thickness: An uncured film having a thickness of 25 μm is heat-cured (200 ° C., 60 min) to prepare a cured film, and an autograph (Shimadzu Corporation ASG-J-5kNJ) is used to measure the tensile modulus at room temperature. I asked. In addition, it measured at n = 3 and used the average value. The tensile modulus is preferably 200 to 2500 MPa. Table 7 shows the evaluation results of the elastic modulus (tensile elastic modulus).

[Evaluation of surface roughness]
Using the metal-coated insulator prepared by the above method, a test piece having a metal film removed by etching, washing (water washing) and drying (50 ° C., 60 min) was produced. The etching was performed by immersing in an etching solution (etching solution H-1000A manufactured by Sunhayato) for 10 minutes, visually confirming that the Cu foil could be removed, taking out, washing with water and drying.
The surface roughness (Rzjis) of the obtained sample was measured using a confocal microscope (Lasertec Corp. OPTELICS H1200) (analysis range 0.9 mm ² , 5-point average roughness). The surface roughness (Rzjis) of the insulator is preferably 1 μm or less.

[Evaluation of plating property]
The plating property was evaluated visually. In each step of electroless plating and electroplating, plating peeling and blistering occurred in a wide range (area of 30% or more) ×, partial (area of 1% or more and less than 30%) generated △ No peeling, swelling, and even completion of the electroplating process were marked with ◯.

[Evaluation of peel strength]
The insulator with a metal coating, which has been subjected to the above-mentioned surface modification and plating steps, is cut into a width of 10 mm, and the portion of the metal coating is peeled off by an autograph (Shimadzu Corporation ASG-J-5kNJ) to obtain peel strength. It was measured. With respect to the measurement results, an average value of N = 5 was calculated. The peel strength is preferably 6 N / cm or more. The results are shown in Table 7.

[Evaluation of transmission loss]
By the method described above, a metal-coated insulator having metal coatings on both sides of a cured film was produced (corresponding to the sample of Example 4). In addition, an insulator having electrolytic copper foils was prepared on both sides of the cured film by the method described above (corresponding to the sample of Comparative Example 4). The wiring width was adjusted so that the impedance was 50Ω, and microstrip lines were produced (pattern length: 100 mm). Using this test piece, the transmission loss up to 20 GHz was measured (manufactured by E8363B Agilent Technologies). The results are shown in FIG. Lower transmission losses are preferred in high frequency applications.

  As can be seen from Table 7, Examples 1 to 6 were good results in all of the elastic modulus, surface roughness, plating property, peel strength, and heat resistance. Although not described in Table 1, the dielectric constant (ε) at a frequency of 10 GHz of Examples 1 to 6 is 2.3 to 2.8, and the dielectric loss tangent (tan δ) is 0.0005 to 0.005. there were. On the other hand, in Comparative Example 1 in which SBR was used instead of the component (B), the plating property was poor. In Comparative Example 2 in which COP was used instead of the component (A) and the component (B), the glass transition temperature and the elastic modulus were low, and the heat resistance was poor. Comparative Example 3 in which LCP was used instead of the component (A) and the component (B) had a low elastic modulus and poor plating properties.

  As described above, the metal-coated insulator of the present invention has excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating. Further, the semiconductor device of the present invention has high reliability because it has an insulator with excellent high-frequency characteristics, excellent heat resistance, and high adhesive strength between the insulator and the metal coating.

Claims (6)

A resin composition comprising (A) a resin and (B) a styrenic block copolymer in which an unsaturated double bond of a main chain in a molecule is hydrogenated, and having a glass transition temperature (Tg) of 150 ° C. or higher. insulator is, and on at least one side surface of the insulator, there is converted by the -OH group and / or -C = O group, characterized by having a metal plating film on the surface, with metal-plated coating film Insulator.   The metal-coated insulator according to claim 1, wherein the insulator has a glass transition temperature (Tg) of 180 ° C. or higher.   The insulator with a metal coating according to claim 1 or 2, wherein the insulator has an elastic modulus of 100 MPa to 2 GPa.   The insulator with a metal coating according to any one of claims 1 to 3, wherein a surface roughness (Rzjis) of the insulator at an interface between the insulator and the metal coating is 1 µm or less.   A semiconductor device comprising the insulator with a metal film according to claim 1. A resin composition comprising (I) (A) resin and (B) a styrene block copolymer in which an unsaturated double bond of the main chain in the molecule is hydrogenated, and having a glass transition temperature (Tg) of 150. A step of forming an insulator of ℃ or higher,
(II) A step of performing ultraviolet irradiation in an oxygen atmosphere, electroless plating, and electrolytic plating on the formed insulator in this order to form a metal plating film,
Is provided in this order, and a method for producing an insulator with a metal plating film.