JP5138185B2 - Printed wiring board - Google Patents

Description

  The present invention relates to a wiring member and a printed wiring board for constituting a printed wiring board.

In recent years, a ubiquitous society has been visited, and in information processing equipment, communication equipment, etc., especially in personal computers, mobile phones, game machines, etc., MPU speedup, multi-functionality, compounding, and speedup of recording devices such as memory are progressing. doing.
However, there is a problem in that the noise radiated from these devices or the noise conducted through a conductor in the device causes malfunction of itself or other electronic devices or parts, and influence on the human body. These noises include noise due to impedance mismatch of conductors in printed wiring boards on which MPUs, electronic components, etc. are mounted, noise due to crosstalk between conductors, power supply layer and ground layer due to simultaneous switching of semiconductor elements such as MPU There is noise induced by resonance between layers.

The following printed wiring boards are known as printed wiring boards in which these noises are suppressed.
(1) A printed wiring board in which a metal film made of a metal having a higher resistivity than a copper foil is formed on both surfaces of a power supply layer and a ground layer made of copper foil (Patent Document 1).
(2) Printed wiring board in which films having anisotropic conductivity in the direction perpendicular to the printed wiring board surface including a conductive material are formed on both surfaces of a power supply layer and a ground layer made of copper foil (Patent Document 1) .

  In the printed wiring board of (1), the high-frequency eddy current that flows on the copper foil surface can be attenuated, and even if the semiconductor element causes simultaneous switching, the power supply potential can be stabilized, and unnecessary noise emission is suppressed. It is supposed to be possible. In order to attenuate the high-frequency current (skin current) flowing on the conductor surface (skin) with a metal film of several μm, which is about the same as the depth of the skin, depending on the frequency of the target high-frequency current, A material having a high resistivity is required. However, such a material cannot be obtained, and the printed wiring board of (1) cannot obtain a sufficient noise suppression effect.

Similarly, in the printed wiring board (2), the high-frequency eddy current can be attenuated. However, forming an anisotropically conductive film so as to have a copper foil surface roughness equal to or greater than the depth of the skin is a complicated process. Further, in the printed wiring board (2), a sufficient noise suppressing effect cannot be obtained.
JP-A-11-97810 JP 2006-66810 A

  Accordingly, an object of the present invention is to suppress the resonance between the power supply layer and the ground layer due to simultaneous switching, thereby stabilizing the power supply potential and suppressing unnecessary noise emission, and a wiring member for a printed wiring board, It is providing the printed wiring board which comprises a wiring member.

The printed wiring board of the present invention is a printed wiring board having a signal wiring layer, a ground layer, and a power supply layer, and includes a copper foil having a smooth surface with a surface roughness Rz of 2 μm or less, and a metal or conductive ceramics. A noise suppression layer having a thickness of 5 to 200 nm, an insulating resin layer provided between the smooth surface side of the copper foil and the noise suppression layer, and a smooth surface side of the copper foil and the insulating resin layer. A wiring member having a thickness of the insulating resin layer of 0.1 to 10 μm , and the copper foil is the power supply layer or the ground layer, The power supply layer or the ground layer exists between the signal wiring layer and the noise suppression layer .
The noise suppression layer preferably has a defect in which no metal or conductive ceramic exists.

The printed wiring board of the present invention preferably has an adhesion promoting layer on the surface of the noise suppression layer opposite to the copper foil side.

In the printed wiring board of the present invention, it is preferable that the copper foil is a power supply layer, and the noise suppression layer is disposed between the power supply layer and the ground layer.

According to the wiring member of the present invention, by suppressing the resonance between the power supply layer and the ground layer due to simultaneous switching in the printed wiring board, the power supply potential can be stabilized and unnecessary noise emission can be suppressed.
In the printed wiring board of the present invention, resonance between the power supply layer and the ground layer due to simultaneous switching is suppressed, the power supply potential is stabilized, and unnecessary noise emission is suppressed.

<Wiring member>
FIG. 1 is a schematic cross-sectional view showing an example of a wiring member in the present invention. The wiring member 10 includes a copper foil 11, an insulating resin layer 12 provided on the copper foil 11, and a noise suppression layer 13 formed on the surface of the insulating resin layer 12.

(Copper foil)
Examples of the copper foil 11 include electrolytic copper foil and rolled copper foil.
Usually, the surface of the copper foil is roughened by, for example, attaching fine copper particles to the surface in order to improve the adhesion to the insulating resin layer 12. On the other hand, in the present invention, the surface of the copper foil 11 on the noise suppression layer 13 side is a smooth surface having a surface roughness Rz of 2 μm or less. If the surface roughness Rz of the smooth surface is 2 μm or less, even if the insulating resin layer 12 is formed thin, defects such as pinholes due to irregularities on the surface of the copper foil 11 are less likely to occur in the insulating resin layer 12. Moreover, the short circuit with the copper foil 11 and the noise suppression layer 13 is suppressed, and sufficient noise suppression effect is acquired. The surface roughness Rz is a ten-point average roughness Rz defined in JIS B 0601-1994.

As the copper foil 11, an electrolytic copper foil is particularly preferable. The electrolytic copper foil is obtained by depositing copper on the surface of the rotating drum of the cathode using an electrolytic reaction and peeling it from the rotating drum. The surface in contact with the drum is transferred with the surface state of the drum. It becomes a smooth surface. On the other hand, the shape of the surface on which copper is electrolytically deposited is a rough surface because the crystal growth rate of the deposited copper differs for each crystal surface, and is convenient for bonding to other insulating resin layers (not shown). It has become.
The thickness of the copper foil 11 is preferably 3 to 50 μm.

(Insulating resin layer)
The insulating resin layer 12 is a layer made of a resin composition or a layer made of a fiber reinforced resin obtained by impregnating a reinforcing fiber such as a glass fiber with the resin composition. The state of the fiber reinforced resin may be B-stage (semi-cured state) or C-stage (cured state).

  A resin composition is a composition which has resin as a main component. The resin preferably has heat resistance required for the printed wiring board and can withstand the heating during the production of the printed wiring board, and is necessary for the design of the printed wiring board such as dielectric constant and dielectric loss tangent. Those having known characteristic values are preferred. Examples of the resin include polyimide resin, epoxy resin, bismaleimide triazine resin, polytetrafluoroethylene, polyphenylene ether and the like.

As a resin composition, what contains an epoxy resin and a hardening | curing agent, a hardening accelerator, a flexibility imparting agent, etc. as needed is preferable.
Epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, novolac type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, brominated epoxy resin, glycidylamine type epoxy resin. Etc. As for the quantity of an epoxy resin, 20-80 mass% is preferable among 100 mass% of resin compositions.

Curing agents include amines such as dicyandiamide, imidazoles and aromatic amines; phenols such as bisphenol A and brominated bisphenol A; novolacs such as phenol novolac resin and cresol novolac resin; acid anhydrides such as phthalic anhydride Etc.
Examples of the curing accelerator include tertiary amines, imidazole curing accelerators, urea curing accelerators, and the like.

Examples of the flexibility imparting agent include polyether sulfone resin, aromatic polyamide resin, and elastic resin.
Aromatic polyamide resins include those synthesized by condensation polymerization of aromatic diamines and dicarboxylic acids. Examples of the aromatic diamine include 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylsulfone, m-xylenediamine, 3,3′-oxydianiline and the like. Examples of the dicarboxylic acid include dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and fumaric acid.
Examples of the elastic resin include natural rubber, styrene-butadiene rubber, butadiene rubber, butyl rubber, and ethylene-propylene rubber. In order to ensure the heat resistance of the insulating resin layer 12, nitrile rubber, chloroprene rubber, silicone rubber, or urethane rubber may be used in combination. As the nitrile rubber, CTBN (carboxy group-terminated butadiene nitrile rubber) is preferable.

  The insulating resin layer 12 is formed, for example, by applying a varnish obtained by dissolving or dispersing a resin composition in a solvent on the copper foil 11 (or on an adhesion promoting layer 15 described later) and drying it. Moreover, the application and drying of the varnish may be performed twice or more to form two or more insulating resin layers. The varnish may be the same type of varnish in each layer, or may be a different type for each layer.

  The thickness of the insulating resin layer 12 is preferably 0.1 to 10 μm. If the thickness of the insulating resin layer 12 is 0.1 μm or more, the insulation between the copper foil 11 and the noise suppression layer 13 is sufficiently maintained, and a short circuit between the copper foil 11 and the noise suppression layer 13 is suppressed, which is sufficient. Noise suppression effect can be obtained. Further, when patterning the copper foil 11 by etching, the noise suppression layer 13 is not affected by the etching. On the other hand, if the thickness of the insulating resin layer 12 is 10 μm or less, the printed wiring board including the wiring member can be thinned. Moreover, when the noise suppression layer 13 and the copper foil 11 approach, the electromagnetic coupling of the noise suppression layer 13 and the copper foil 11 becomes strong, and a sufficient noise suppression effect is obtained. In addition, when pattern processing is performed on the noise suppression layer 13 from the copper foil 11 side, the insulating resin layer 12 can be easily removed, and the processing time is shortened.

(Noise suppression layer)
The noise suppression layer 13 is a thin film having a thickness of 5 to 200 nm containing a metal material or conductive ceramics.
If the thickness of the noise suppression layer 13 is 5 nm or more, a sufficient noise suppression effect can be obtained. On the other hand, when the thickness of the noise suppression layer 13 exceeds 200 nm, microclusters to be described later grow, a homogeneous thin film made of a metal material or the like is formed, the surface resistance is reduced, the metal reflection is increased, and the noise suppression effect. Becomes smaller.
The thickness of the noise suppression layer 13 is determined based on the high-resolution transmission electron microscope image (for example, FIG. 4) of the cross section in the film thickness direction of the noise suppression layer. Thickness is determined by measuring on an electron microscope image and averaging.

The surface resistance of the noise suppression layer 13 is preferably 10 ⁰ to 10 ⁴ Ω. In the case where the noise suppression layer 13 is a homogeneous thin film, a limited material having a high volume resistivity is required. However, when the volume resistivity of the material is not so high, a metal material or conductive ceramic is formed on the noise suppression layer 13. The surface resistance can be increased by providing a non-existing physical defect to form an inhomogeneous thin film. The surface resistance of the noise suppression layer 13 is measured as follows.
A thin film metal electrode such as a gold vapor deposition electrode having two unit lengths is pressed against a measurement electrode separated by a unit length with a constant load of 50 g / cm ² , The resistance between the electrodes is measured with a measurement current of 1 mA or less. This value is used as the surface resistance.

  Examples of the metal material include ferromagnetic metals and paramagnetic metals. Ferromagnetic metals include iron, carbonyl iron; Fe-Ni, Fe-Co, Fe-Cr, Fe-Si, Fe-Al, Fe-Cr-Si, Fe-Cr-Al, Fe-Al-Si, Fe -Pt and other iron alloys; cobalt and nickel; and alloys thereof. Examples of the paramagnetic metal include gold, silver, copper, tin, lead, tungsten, silicon, aluminum, titanium, chromium, molybdenum, alloys thereof, amorphous alloys, and alloys with ferromagnetic metals. Of these, nickel, iron-chromium alloy, tungsten, and noble metals are preferred because of their resistance to oxidation. In addition, since noble metals are expensive, practically, nickel, nickel chromium alloy, iron chromium alloy, and tungsten are preferable, and nickel or nickel alloy is particularly preferable.

  Examples of the conductive ceramic include an alloy, an intermetallic compound, a solid solution, and the like including a metal and one or more elements selected from the group consisting of boron, carbon, nitrogen, silicon, phosphorus, and sulfur. Specific examples include nickel nitride, titanium nitride, tantalum nitride, chromium nitride, titanium carbide, zirconium carbide, chromium carbide, molybdenum carbide, tungsten carbide, silicon carbide, chromium boride, and molybdenum boride.

  Since conductive ceramics have a higher volume resistivity than metals, the noise suppression layer containing conductive ceramics does not have a specific resonance frequency, the frequency that exhibits the noise suppression effect is widened, and the storage stability is high. Advantages such as high. As the conductive ceramics, those made of metal and nitrogen are particularly preferable because they can be easily obtained by using nitrogen gas as a reactive gas in the physical vapor deposition method described later.

  Examples of a method for forming the noise suppression layer 13 include a normal wet plating method, a physical vapor deposition method, and a chemical vapor deposition method. In this method, although it depends on the conditions and materials used, by terminating the growth of the thin film at an early stage, it is not possible to form a homogeneous thin film but to form a heterogeneous thin film having fine physical defects. . Alternatively, an inhomogeneous thin film can also be formed by a method of forming a defect by etching a homogeneous thin film with an acid or the like, or a method of forming a defect by a laser ablation.

  FIG. 2 is a field emission scanning electron microscope image obtained by observing the surface of the noise suppression layer made of a metal material formed on the surface of the insulating resin layer by physical vapor deposition, and FIG. 3 is a schematic diagram thereof. The noise suppression layer 13 is observed as an aggregate of a plurality of microclusters 14. The microclusters 14 are formed by physically depositing a metal material on the insulating resin layer 12 so as to be physically thin, and there are physical defects between the microclusters 14 to form a homogeneous thin film. Not. Although the microclusters 14 are in contact with each other and are clustered, there are many defects in which no metal material exists between the clustered microclusters 14.

FIG. 4 is a high-resolution transmission electron microscope image of a cross section in the film thickness direction of the noise suppression layer 13. 2 and 4, a crystal lattice (microcluster) in which metal atoms arranged at intervals of several kilometers are arranged as very small crystals, and defects in which a metal material does not exist in a very small range are recognized. That is, the microclusters are spaced apart from each other and have not grown into a homogeneous thin film made of a metal material. The state having such a physical defect is that the volume resistivity R ₁ (Ω · cm) converted from the measured value of the surface resistance of the noise suppression layer 13 and the volume resistivity R _{0 of the} metal material (or conductive ceramic). It can be confirmed from the relationship with (Ω · cm) (document value). That is, when the volume resistivity R ₁ and the volume resistivity R ₀ satisfy 0.5 ≦ logR ₁ −logR ₀ ≦ 3, an excellent noise suppression effect is exhibited.

  The noise suppression layer 13 may be patterned into a desired shape, and an anti-via such as a through hole may be formed. The noise suppression layer 13 can be processed into a desired shape by a normal etching method, a laser ablation method, or the like.

(Adhesion promoting layer)
In order to improve the adhesion between the copper foil 11 and the insulating resin layer 12, the adhesion promoting layer 15 is preferably provided on the smooth surface of the copper foil 11.
The adhesion promoting layer 15 is formed by treating the smooth surface of the copper foil 11 with an adhesion promoter. Examples of the adhesion promoter include a silane coupling agent or a titanate coupling agent.

  Examples of silane coupling agents include vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 2- (3,4-epoxycyclohexyl). ) Ethyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl- Examples include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-chloropropyltrimethoxysilane.

  Titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, tetraoctyl bis (di-tridecyl phosphite) titanate, bis (Dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyldimethacrylisostearoyl titanate, isopropylisostearoyldiacryl titanate, tetraisopropylbis (dioctylphosphite) titanate It is done.

As the adhesion promoter, 3-glycidoxypropyltrimethoxysilane is usually used. When the peel strength between the copper foil 11 and the insulating resin layer 12 is increased to 1.0 kgf / cm or more, 3-mercapto is used. Propyltrimethoxysilane is preferred.
Examples of the method for forming the adhesion promoting layer 15 include a coating method, a dipping method, a showering method, and a spraying method.

Further, an adhesion promoting layer (not shown) may be provided on the noise suppressing layer 13 in order to improve the adhesion between the noise suppressing layer 13 and another insulating resin layer (not shown).
The adhesion promoting layer can be formed by a method of applying the silane coupling agent or titanate coupling agent, a method of applying an epoxy resin in which the coupling agent is integral blended, or the like. The adhesion promoting layer may be formed after pattern processing of the noise suppression layer 13.

<Printed wiring board>
The printed wiring board of the present invention comprises the wiring member of the present invention. The copper foil in the wiring member is a signal wiring layer, a power supply layer, or a ground layer in the printed wiring board. In order to sufficiently exhibit the noise suppressing effect, the copper foil in the wiring member is preferably a power supply layer or a ground layer, and more preferably a power supply layer. In order to sufficiently exhibit the noise suppression effect, it is preferable that a noise suppression layer is disposed between the power supply layer and the ground layer.

  FIG. 5 is a schematic sectional view showing an example of the printed wiring board of the present invention. In the printed wiring board 20, a patterned signal wiring layer 21, a ground layer 22, a power supply layer 23, and a patterned signal wiring layer 21 over almost the entire surface of the printed wiring board 20 are arranged via an insulating layer 24 in order from the top. Are stacked.

  The power supply layer 23 is the copper foil 11 of the wiring member 10, and the noise suppression layer 13 having the same size as the ground layer 22 is provided on the ground layer 22 side of the power supply layer 23 via the insulating resin layer 12. It has been. The power supply layer 23 is divided into two parts, and the divided power supply layers 23 are insulated from each other.

The printed wiring board 20 is manufactured as follows, for example.
A prepreg made by impregnating glass fiber or the like with epoxy resin or the like is sandwiched between the wiring member 10 and another copper foil and cured, and the copper foil 11 of the wiring member 10 is grounded to the power supply layer 23 and the other copper foil is grounded. Layer 22 is assumed.
Next, the copper foil 11 of the wiring member 10 is etched so as to have a desired shape (two-divided pattern) by a photolithography method or the like. At this time, since the insulating resin layer 12 is resistant to the etching solution and the insulating resin layer 12 does not have pinholes, the noise suppression layer 13 exists without being damaged by etching. A power wiring layer 23 and a ground layer 22 are used as a core, and a copper foil is bonded to both outer surfaces with a prepreg to form a signal wiring layer 21.

  In the wiring member of the present invention described above, a copper foil having a smooth surface with a surface roughness Rz of 2 μm or less, a noise suppression layer having a thickness of 5 to 200 nm, including metal or conductive ceramics, Since the insulating resin layer provided between the smooth surface side of the copper foil and the noise suppression layer is provided, the insulation between the copper foil and the noise suppression layer can be sufficiently ensured.

  In the printed wiring board of the present invention described above, since the wiring member of the present invention is provided, the noise suppression layer attenuates the high-frequency current flowing into the power supply layer by simultaneous switching, and the power supply layer and the ground layer are The resonance between them can be suppressed. As a result, noise emission from the peripheral edge of the substrate can be suppressed.

(Noise suppression layer thickness)
The cross section of the noise suppression layer was observed using a transmission electron microscope H9000NAR manufactured by Hitachi, Ltd., and the thicknesses of the five noise suppression layers were measured and averaged.

(Adhesive strength)
The peel strength between the copper foil of the wiring member and the insulating resin layer was measured with Tensilon at a tensile angle of 90 ° and a tensile speed of 50 mm / min in accordance with JIS C5012.

(Noise suppression effect)
A two-layer substrate consisting of a ground layer and a power supply layer is manufactured, and an SMA connector connected to the power supply layer and the ground layer is mounted on both ends of one of the two power supply layers, and a network analyzer ( S21 (transmission attenuation, unit: dB) by the S parameter method was measured using 37247D manufactured by Anritsu Corporation, and the resonance state of the S21 parameter was confirmed. When there is a noise suppression effect, the amount of attenuation at the resonance frequency increases, and the graph showing the amount of attenuation and frequency becomes smooth.

(Power supply interlayer resistance)
A probe was applied to each of the two divided power supply layers, and the resistance between the power supply layers when a measurement voltage of 50 V was applied was measured using a superinsulator SM-8210 manufactured by Toa DKK.

[Example 1]
On the smooth surface of an electrolytic copper foil having a thickness of 35 μm, the surface roughness Rz of one surface (smooth surface) is 2 μm and the surface roughness Rz of the other roughened surface is 5.3 μm. A 1% by mass 3-glycidoxypropyltrimethoxysilane solution was applied and dried to form an adhesion promoting layer.

30 parts by mass of bisphenol A type epoxy resin (made by Japan Epoxy Resin Co., Ltd., 828), 30 parts by mass of brominated bisphenol A type resin (produced by Toto Kasei Co., Ltd., YDB-500) and cresol novolac resin (manufactured by Toto Kasei Co., Ltd., YDCN-704) ) 35 parts by mass was dissolved in methyl ethyl ketone, and then 0.2 part by mass of an imidazole curing accelerator (manufactured by Shikoku Kasei Co., Ltd., Curazole 2E4MZ) was added to prepare a varnish of 8% by mass of a resin composition.
The varnish of the resin composition was applied onto the adhesion promoting layer using a gravure coater so that the thickness after drying was 10 μm to form a coating film. The coating film was air-dried for 15 minutes and then cured by heating at 150 ° C. for 15 minutes to form an insulating resin layer.

  Next, nickel metal was physically deposited on the entire surface of the insulating resin layer by EB deposition. The insulating resin layer was further cured by heating at 150 ° C. for 45 minutes to form a 15 nm thick heterogeneous noise suppression layer having the surface shown in FIG. 2, thereby obtaining a wiring member having a total thickness of 45 μm.

  A strip-shaped test piece having a width of 10 mm and a length of 100 mm is cut out from the wiring member, three test pieces are arranged in the width direction of a prepreg having a width of 35 mm, a length of 50 mm, and a thickness of 1 mm, and the test piece and the prepreg are pressed. After bonding, the peel strength was measured and the peeled state was observed. The results are shown in Table 1. The peel strength was the average value of the three test pieces.

  The wiring member and a copper foil having a thickness of 35 μm were integrated through a prepreg having a thickness of 0.2 mm to produce a two-layer substrate. A test piece having a size of 74 mm × 160 mm is cut out from the two-layer substrate, and the copper foil on the wiring member side of the test piece is divided into two power supply layers having a size of 36.5 mm × 160 mm by etching and separated by 1 mm. Arranged. The size of the noise suppression layer and the ground layer was 74 mm × 160 mm. About this test piece, the power supply interlayer resistance was measured. The results are shown in Table 1. Moreover, about this test piece, S21 by S parameter method was measured. The results are shown in FIG.

[Example 2]
On the smooth surface of an electrolytic copper foil having a thickness of 18 μm, the surface roughness Rz of one surface (smooth surface) is 0.4 μm and the surface roughness Rz of the other roughened surface is 5.3 μm. 1 mass% of 3-mercaptopropyltrimethoxysilane solution was applied and dried to form an adhesion promoting layer.

95 parts by mass of polyethersulfone resin (Sumitomo Chemical Co., PES5003P), 5 parts by mass of bisphenol A type epoxy resin (Japan Epoxy Resin Co., Ltd., 828EL), imidazole-based curing accelerator (Shikoku Kasei Co., Ltd., Curesol 2MZ) 0.1 part by mass was dissolved in an N, N-dimethylformamide / cyclohexane mixed solvent (50/50 mass ratio) to prepare a varnish A of 0.5% by mass of a resin composition.
Varnish A of the resin composition was applied on the adhesion promoting layer so that the thickness after drying was 1 μm to form a coating film. The coating film was air-dried for 10 minutes and then cured by heating at 160 ° C. for 10 minutes to form an insulating resin layer A.

26 parts by mass of bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., 834), 20 parts by mass of bisphenol A type phenoxy resin (manufactured by Japan Epoxy Resin Co., 1256), 35 parts by weight of cresol novolac resin (YDCN-704, manufactured by Toto Kasei Co., Ltd.) A part by mass was dissolved in methyl ethyl ketone, and then 0.2 part by mass of an imidazole curing accelerator (manufactured by Shikoku Kasei Co., Ltd., Curazole 2E4MZ) was added to prepare varnish B of 4% by mass of a resin composition.
Varnish B of the resin composition was applied onto insulating resin layer A using a gravure coater so that the thickness after drying was 2 μm to form a coating film. The coating film was air-dried for 10 minutes and then cured by heating at 150 ° C. for 15 minutes to form an insulating resin layer B.

Next, tantalum metal was physically deposited on the entire surface of the insulating resin layer B by magnetron sputtering while nitrogen was introduced. The insulating resin layer was further cured by heating at 150 ° C. for 45 minutes to form a heterogeneous noise suppression layer having a thickness of 20 nm, and a wiring member having a total thickness of 21 μm was obtained.
About this wiring member, it carried out similarly to Example 1, and measured the peeling strength and observed the peeling state. The results are shown in Table 1.

  The wiring member and a copper foil having a thickness of 18 μm were integrated through a prepreg having a thickness of 0.1 mm to produce a two-layer substrate. For the two-layer substrate, the power supply layer was divided into two in the same manner as in Example 1, a test piece was prepared, and the power supply interlayer resistance was measured. The results are shown in Table 1. Moreover, about this test piece, S21 by S parameter method was measured. The results are shown in FIG.

[Comparative Example 1]
Wiring with a total thickness of 45 μm was used in the same manner as in Example 1 except that a roughened electrolytic copper foil with a thickness of 35 μm having a surface roughness Rz of both surfaces was 5.3 μm and no adhesion promoting layer was formed. A member was obtained. About this wiring member, it carried out similarly to Example 1, and measured the peeling strength and observed the peeling state. The results are shown in Table 1.
Using the wiring member, a two-layer substrate was produced in the same manner as in Example 1, a test piece was produced in the same manner as in Example 1, and the power supply interlayer resistance was measured. The results are shown in Table 1. S21 was not measured by the S parameter method.

[ Reference Example 1 ]
A wiring member was obtained in the same manner as in Example 1 except that the adhesion promoting layer was not formed and the thickness of the insulating resin layer was 25 μm. About this wiring member, it carried out similarly to Example 1, and measured the peeling strength and observed the peeling state. The results are shown in Table 1.
Using the wiring member, a two-layer substrate was produced in the same manner as in Example 1, a test piece was produced in the same manner as in Example 1, and the power supply interlayer resistance was measured. The results are shown in Table 1. Moreover, about this test piece, S21 by S parameter method was measured. The results are shown in FIG.

[Comparative Example 2]
A wiring member having a total thickness of 18 μm was obtained in the same manner as in Example 2 except that the noise suppressing layer was directly formed on the copper foil without providing the insulating resin layer. About this wiring member, it carried out similarly to Example 1, and measured the peeling strength and observed the peeling state. The results are shown in Table 1.

  A two-layer substrate was produced using the wiring member in the same manner as in Example 1. With respect to the two-layer substrate, the power source layer was divided into two and the test piece was produced in the same manner as in Example 1. However, since there was no insulating resin layer, the noise suppression layer was also divided and the same as the power source layer 2 It became the divided | segmented magnitude | size (36.5 mm x 160 mm). The size of the ground layer was 74 mm × 160 mm. About this test piece, the power supply interlayer resistance was measured. The results are shown in Table 1. Moreover, about this test piece, S21 by S parameter method was measured. The results are shown in FIG.

[Comparative Example 3]
A wiring member was obtained in the same manner as in Example 1 except that no noise suppression layer was formed. Using the wiring member, a two-layer substrate was produced in the same manner as in Example 1, a test piece was produced in the same manner as in Example 1, and S21 by the S parameter method was measured. The results are shown in FIGS.

[Comparative Example 4]
A wiring member was obtained in the same manner as in Comparative Example 2 except that no noise suppression layer was formed. Using the wiring member, a two-layer substrate was produced in the same manner as in Example 1, a test piece was produced in the same manner as in Example 1, and S21 by the S parameter method was measured. The results are shown in FIG.

  The wiring member of the present invention is useful as a member constituting a printed wiring board that supplies power and transmits signals to semiconductor elements such as IC and LSI and electronic components.

It is a schematic sectional drawing which shows an example of the wiring member of this invention. It is the field emission scanning electron microscope image which observed the surface of the noise suppression layer. FIG. 3 is a schematic diagram of FIG. 2. 3 is a high-resolution transmission electron microscope image of a cross section of the noise suppression layer in FIG. 2. It is a schematic sectional drawing which shows an example of the printed wiring board of this invention. It is a graph which shows S21 (transmission attenuation amount) of the printed wiring board of Example 1 and Comparative Example 3. It is a graph which shows S21 (transmission attenuation amount) of the printed wiring board of Example 2 and Comparative Example 3. It is a graph which shows S21 (transmission attenuation amount) of the printed wiring board of Example 3 and Comparative Example 3. It is a graph which shows S21 (transmission attenuation amount) of the printed wiring board of the comparative example 2 and the comparative example 4. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Wiring member 11 Copper foil 12 Insulating resin layer 13 Noise suppression layer 15 Adhesion promotion layer 20 Printed wiring board 22 Ground layer 23 Power supply layer

Claims (4)

A printed wiring board having a signal wiring layer, a ground layer and a power supply layer,
A copper foil having a smooth surface with a surface roughness Rz of 2 μm or less;
A noise suppression layer having a thickness of 5 to 200 nm, including a metal material or conductive ceramics;
An insulating resin layer provided between the smooth surface side of the copper foil and the noise suppression layer;
An adhesion promoting layer provided between the smooth surface side of the copper foil and the insulating resin layer;
A wiring member having a thickness of the insulating resin layer of 0.1 to 10 μm ;
The copper foil is the power supply layer or the ground layer,
A printed wiring board in which the power supply layer or the ground layer exists between the signal wiring layer and the noise suppression layer . The printed wiring board according to claim 1, wherein the noise suppression layer has a defect in which a metal material or conductive ceramic does not exist. The printed wiring board of Claim 1 or 2 which has an adhesion promotion layer in the surface on the opposite side to the said copper foil side of the said noise suppression layer. The copper foil is a power supply layer,
The printed wiring board as described in any one of Claims 1-3 by which the said noise suppression layer is arrange | positioned between the power supply layer and the ground layer.

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