KR20160103519A - Circuit board and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a technology for forming a via hole, which has a small diameter while being in a fine via hole shape, on an insulation layer including an inorganic filler when a circuit board is manufactured. The circuit board includes the insulation layer having the via with a diameter of 15 m or less. The arithmetic average roughness of the surface of the insulation layer (Ra) is 150 nm or less. The insulation layer includes the inorganic filler. For the cross-section of the insulation layer in a vertical direction of the surface of the insulation layer, the value of n11.27 (n2) is 0.2 m or less when the average value of the maximum diameter of the inorganic filler included in an area of a predetermined width is set to be n1 (m).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a circuit board,

The present invention relates to a circuit board and a manufacturing method thereof.

BACKGROUND ART [0002] Circuit boards widely used in various electronic apparatuses are required to miniaturize circuit wirings and increase the density thereof in order to make electronic apparatuses smaller and more sophisticated. BACKGROUND ART [0002] As a manufacturing technique of a circuit board, a manufacturing method by a build-up method in which an insulating layer and a conductor layer are alternately superimposed on an inner layer substrate is known. In the manufacturing method according to the build-up method, the insulating layer is formed by laminating the resin composition layer on the inner layer substrate using, for example, an adhesive film comprising a support and a resin composition layer provided on the support, And is cured. Subsequently, via holes are formed in the formed insulating layer by a laser to perform a desmear treatment, thereby removing the resin residue (smear) in the via-hole and roughening the surface of the insulating layer (For example, Patent Document 1).

Patent Document 1: JP-A-2008-37957

In order to achieve higher density of the circuit wiring, it is desired to reduce the diameter of the via hole. Via holes are generally formed by laser drilling, and carbonaceous gas lasers, which are fast in puncturing speed and favorable in manufacturing cost, are currently in use. However, there is a limit to the formation of a via-hole in a small-size hole, and it is difficult to form a via hole having an opening diameter of 25 占 퐉 or less by, for example, a carbon dioxide gas laser.

Examples of the laser usable for forming the via-hole include a carbon dioxide gas laser and a UV solid-state laser such as a UV-YAG laser. The UV solid-state laser is not so used for the formation of the via-hole. Generally, since a strong ultraviolet region laser can be obtained, unlike an infrared laser such as a carbon dioxide gas laser, no heat is generated. Therefore, finer machining is possible and it is expected to contribute to the hardening of the via hole.

On the other hand, in order to cope with high-speed signal transmission, the dielectric constant of the insulating layer has been lowered, and it is preferable to include an inorganic filler in the insulating layer.

The present inventors have tried to form a via hole having a small diameter by a UV solid laser such as a UV-YAG laser on an insulating layer containing an inorganic filler. As a result, it has been found that the laser machinability is deteriorated and the shape of the via hole (also simply referred to as " via shape ") may deteriorate. Particularly, when the content of the inorganic filler in the insulating layer is increased in order to achieve an insulating layer having a low dielectric constant, this becomes a serious problem. It has also been found that the same problem arises when the value of the arithmetic mean roughness (Ra) of the insulating layer forming the via hole by the UV solid laser is high. The deterioration of the via shape causes deterioration of the conduction reliability, and the increase of the amount of smear in the via-hole necessitates the desmear treatment under strict conditions, which hinders miniaturization of the circuit wiring.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technique capable of forming a via-hole with a small diameter and having a good via shape in an insulating layer containing an inorganic filler when a circuit board is manufactured.

As a result of intensive studies on the above problems, the inventors of the present invention have found that by producing a circuit board using a predetermined inorganic filler, the above problems can be solved and the present invention has been completed.

That is, the present invention includes the following contents.

[1] A circuit board comprising an insulating layer having a via-hole having an opening diameter of 15 탆 or less,

The arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less,

Wherein the insulating layer comprises an inorganic filler,

When the average value of the maximum diameter of the inorganic filler contained in the region of the predetermined width is n ¹ (탆) in the cross section of the insulating layer in the direction perpendicular to the surface of the insulating layer, a value n ¹ × 1.27 (n ² ) is 0.2 탆 or less.

[2] The circuit board according to item [1], wherein the surface of the insulating layer has an Ra of 100 nm or less.

[3] The circuit board according to item [1] or [2], wherein the opening diameter of the via-hole is 12 μm or less.

[4] the above items [1] to [3] according to any one of, wherein the surface of the insulating layer of such insulating layers in the vertical cross section, a resin area in a predetermined width zone of (A ₁₎ and an inorganic filler area (a ₂₎ is _{0.1≤A 2 / (a 1 + a} 2), a circuit board satisfying.

[5] the above items [1] to [4] The method according to any one of, wherein the via-hole opening diameter (D) and the via-hole in the minimum diameter (D _min), the circuit board to satisfy the 0.65≤D _min / D.

[6] The circuit board according to any one of items [1] to [5], wherein the insulating layer comprises an inorganic filler surface-treated with a silane compound containing an organic group having an aromatic ring.

[7] The circuit board according to any one of items [1] to [6], wherein the inorganic filler is silica.

[8] A semiconductor device comprising the circuit board according to any one of items [1] to [7].

[9] A method of manufacturing a semiconductor device, comprising the steps of: (A) laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,

Wherein the insulating layer formed in the step (B) includes an inorganic filler and an average value of a maximum diameter of the inorganic filler contained in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is n ¹ (N ² ) of n ¹ × 1.27 is not more than 0.2 μm when the thickness (m ² ) is defined as (μm).

(10) A method of manufacturing a semiconductor device, comprising the steps of: (A) laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,

Wherein the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having a BET specific surface area of 20 m ² / g or more.

[11] A method for manufacturing a semiconductor device, comprising the steps of: (A) laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,

Wherein the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having an average particle diameter of 0.2 占 퐉 or less.

[12] The method according to item [10], wherein the inorganic filler has a BET specific surface area of 20 m ² / g or more and 500 m ² / g or less.

[13] The method according to item [11], wherein the inorganic filler has an average particle diameter of 0.01 μm or more and 0.2 μm or less.

[14] The method according to any one of items [9] to [13], wherein the support is removed before the step (C).

[15] The method according to any one of items [9] to [14], wherein an arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less.

[16] The pharmaceutical composition of [9] to [15] as claimed in any one of, wherein the surface of the insulating layer of such insulating layers in the vertical cross section, a resin area in a predetermined width zone of (A ₁₎ and an inorganic filler area (a ₂₎ to satisfy the _{0.1≤A 2 / (a 1 + a} 2), method.

[17] The method according to any one of items [9] to [16], wherein the opening diameter D of the via hole and the minimum diameter D _min of the via hole satisfy 0.65? D _min / D.

[18] The method according to any one of items [9] to [17], wherein the insulating layer comprises an inorganic filler surface-treated with a silane compound containing an organic group having an aromatic ring.

[19] The method according to any one of items [9] to [18], wherein the inorganic filler is silica.

According to the present invention, when manufacturing a circuit board, a via-hole having a small diameter and a good diameter can be formed in the insulating layer containing the inorganic filler.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view for explaining a method of calculating an average value of a maximum diameter of an inorganic filler in a region of a predetermined width in a cross section of an insulating layer. FIG.
2 is a schematic view for explaining a via shape.

First, the concept of the present invention will be described.

In the present invention, a via hole having a small diameter (for example, an opening diameter of 15 탆 or less) is formed in the insulating layer by a UV solid laser while satisfying the following conditions (i) and (ii)

(i) the arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less; And

(ii) When the average value of the maximum diameter included in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is n ¹ (탆), a value n ¹ × 1.27 ² ) is not larger than 0.2 탆.

The inventors of the present invention found that, when a circuit board is manufactured, the insulating layer containing an inorganic filler is subjected to a perforation process by a UV solid laser while satisfying the above-mentioned specific conditions (i) and (ii) It is possible to form a hole.

- Condition (i) -

The condition (i) relates to the arithmetic mean roughness (Ra) of the surface of the insulating layer. The present inventors have found that when a via hole having a small diameter is formed by a UV solid laser, Ra of the surface of the insulating layer greatly affects the via shape.

From the viewpoint of forming a small-diameter via hole having a good via shape, the arithmetic mean roughness (Ra) of the surface of the insulating layer is 150 nm or less, preferably 140 nm or less, more preferably 130 nm or less, , Still more preferably 110 nm or less, particularly preferably 100 nm or less, 90 nm or less, 80 nm or less, or 70 nm or less. The lower limit of the Ra is not particularly limited, but may be usually 1 nm or more, 5 nm or more, 10 nm or more from the viewpoint of stabilizing the adhesion strength between the insulating layer and the conductor layer. The arithmetic mean roughness (Ra) of the surface of the insulating layer can be measured using a non-contact surface roughness meter. A specific example of the non-contact type surface roughness meter is "WYKO NT3300" manufactured by Veeco Instrument.

- Condition (ii) -

The condition (ii) relates to the particle diameter of the inorganic filler in the insulating layer. The present inventors have found that when a via hole with a small diameter is formed by a UV solid laser, the particle diameter of the inorganic filler in the insulating layer greatly affects the via shape.

In view of forming a small-diameter via hole having a good via shape, in the cross section of the insulating layer in the direction perpendicular to the surface of the insulating layer (also simply referred to as " cross section of the insulating layer "), (N ² ) of n ¹ × 1.27 when n ¹ (μm) is n ¹ (μm) is 0.2 μm or less, preferably 0.18 μm or less, more preferably 0.16 μm or less, more preferably 0.14 μm or less, and 0.12 Mu m or less, or 0.1 mu m or less. The lower limit of n ² is not particularly limited, but is usually 0.01 μm or more, preferably 0.02 μm or more, more preferably 0.03 μm or more, 0.04 μm or more, or 0.05 μm or more. Also, it was confirmed that n ² substantially coincided with the average particle diameter of the actual inorganic filler.

The cross-section of the insulating layer can be suitably observed using an FIB-SEM composite device. As the FIB-SEM hybrid device, for example, "SMI3050SE" manufactured by SII Nano Technology Co., Ltd. can be mentioned. After the cross section of the insulating layer in the vertical direction is cut off by the FIB (focused ion beam) on the surface of the insulating layer, the cross section can be observed with an SEM (scanning electron microscope) to obtain a cross-sectional SEM image. The observation width and the observation magnification by the SEM are not particularly limited as long as the maximum diameter of the inorganic filler contained in the region of the predetermined width in the cross section of the insulating layer can be appropriately counted, It is also good.

When the obtained average value (n ¹⁾ of choedaegyeong, refers to a region of the "region having a predetermined width" means the total thickness of the insulating layer in a cross section SEM image (t) (㎛) × width (w) (㎛). The width w is not particularly limited as long as it can be observed in a cross-sectional SEM image. For example, 15 mu m is preferable. That is, it is preferable to obtain the average value (n ¹ ) of the maximum diameter in the area of the total thickness t (占 퐉) of the insulating layer 占 15 (占 퐉) in the cross-sectional SEM image.

The " maximum diameter " means the largest diameter of the inorganic filler particles observed in the cross-sectional SEM image. Further, it is judged that the inorganic filler is included in the area of " width (w) (mu m) " when the amount of the inorganic filler exceeds 1/2 of the maximum diameter in the area of width w (mu m). The method for calculating the average value of the maximum filler diameter will be described in more detail with reference to Fig. Fig. 1 shows a cross section of an insulating layer 10 having a thickness t, which includes a resin component 10 and an inorganic filler 12. Fig. In the section of the insulating layer shown in Fig. 1, the maximum diameter of the inorganic filler selected as a representative is indicated by a chain line. It is judged that the inorganic filler which is contained in the region of the width w (占 퐉) only outside the half of the maximum diameter is not included in the region of the width w (占 퐉). Therefore, regarding the cross-section of the insulating layer shown in Fig. 1, it is judged that the number of inorganic fillers existing in the region of width (w) (占 퐉) is two, and the maximum of these is determined, and the average value of the maximum diameter is calculated. A sufficient number (N ₁ ) of cross-sectional SEM images is obtained for the insulating layer sample, and an average value of the maximum diameters of the inorganic fillers contained in the region of the width w (占 퐉) is obtained to obtain the average value n ¹ . Here, N ₁ is preferably 10 or more. In the present invention, the average value (n ¹ ) of the maximum diameter can be calculated according to the procedure described in < evaluation of the particle diameter of the inorganic filler in the insulating layer >

According to the present invention that satisfies the above conditions (i) and (ii), a via hole having a small diameter and a good diameter can be formed. The problem of the via shape and the amount of internal smear tends to become remarkable as the via hole is hardened by curing. However, according to the method of the present invention, for example, 15 mu m or less, preferably 14 mu m or less, (Top diameter) of not more than 10 mu m, more preferably not more than 9 mu m, not more than 8 mu m, not more than 7 mu m, not more than 6 mu m, or not more than 5 mu m, . The lower limit of the opening diameter of the via-hole is not particularly limited, but may be usually 1 占 퐉 or more, 2 占 퐉 or more, 3 占 퐉 or more, or the like.

As described above, the inventors of the present invention found that when the insulating layer contains an inorganic filler having a large particle diameter in a certain amount or more, the laser processability by the UV solid laser is lowered and the shape of the via hole is deteriorated It was found that the amount of smear in the hole sometimes increased. Particularly, when the content of the inorganic filler is increased, the problem becomes more present. On the other hand, according to the present invention, even when the content of the inorganic filler in the insulating layer is high, a via-hole having a good via shape with a small diameter can be formed in the insulating layer.

The content of the inorganic filler in the insulating layer can be evaluated using the area ratio of the inorganic filler in the cross section of the insulating layer. Specifically, the inorganic filler content in the insulating layer when a predetermined resin, the area of the wide area in the dielectric layer cross-section the A _1, an inorganic filler area to _{A 2, A 2 / (A} 1 + A 2) The value of . &Lt; / RTI > The larger the value of A ₂ / (A ₁ + A ₂ ), the higher the content of inorganic filler in the insulating layer. From the viewpoint of lowering the dielectric constant of the insulating layer, the value of A ₂ / (A ₁ + A ₂ ) is preferably 0.1 or more (that is, 0.1 A ₂ / (A ₁ + A ₂ ) Or more, more preferably 0.25 or more, and even more preferably 0.26 or more. The upper limit of the value of A ₂ / (A ₁ + A ₂ ) is not particularly limited, but is preferably 0.9 or less, more preferably 0.8 or less, from the viewpoint of the mechanical strength and the like of the insulating layer. In the present invention, &quot; resin area &quot; refers to the area occupied by the resin component. The term &quot; resin component &quot; refers to a component other than the inorganic filler among components constituting the insulating layer. The value of A ₂ / (A ₁ + A ₂ ) in the cross-section of the insulating layer can be obtained according to the procedure described in <Measurement of resin area and inorganic filler area in the end face of insulating layer> described later. The area of the predetermined width is as described above.

In the present invention, a via hole having a small diameter is formed in the insulating layer by a UV solid laser while satisfying the above conditions (i) and (ii).

As the UV solid laser, various well-known ones can be used. Examples of the UV solid laser include a UV-YAG laser, a UV-YLF laser and a UV-YTO ₄ laser. Among them, a UV-YAG laser is preferable.

The UV-YAG laser is a kind of UV solid-state laser, in which yttrium, aluminum, garnet (abbreviated as YAG) crystals are doped with other elements to replace part of the yttrium in the crystal structure as a medium for oscillation of solid-state lasers . In general, Nd: YAG doped with neodymium (Nd) is used. A laser beam (wavelength: 355 nm, quadruple wavelength: 266 nm) obtained by converting the wavelength of Nd: YAG laser light using LBO (LiB ₃ O ₅ ) crystal is used. In addition, _{BBO (β-BaB 2 O 4} ) is a laser using a crystal or a KTP (KTiOPO ₄₎ crystal as an element for generating harmonics also used.

(For example, laser wavelength, pulse number, pulse width, output) by a UV solid laser is not particularly limited as long as it can form a via hole of a small diameter having a good via shape, It can be appropriately determined within the range of general processing conditions according to the specification of the solid laser processing machine. The UV solid laser can be a commercially available UV solid laser processing machine, and specifically, a commercially available UV-YAG laser processing machine, for example, "LU-2L212 / M50L" manufactured by Via Mechanics .

According to the method of the present invention in which the conditions (i) and (ii) are satisfied, the method of the present invention in which the hole is processed by the UV solid laser can provide a good via shape (for example, an insulating layer having a high content of inorganic filler) A via hole having a small diameter can be formed.

The shape of the via-hole will be described with reference to Fig. 2 shows an inner layer substrate 1 and an insulating layer 10 having a thickness t provided so as to be bonded to the inner layer substrate. The insulating layer 10 is provided with the typical vias (a) to (c) Holes are formed. In the present invention, the &quot; opening diameter (D) &quot; of the via-hole refers to the diameter of the via-hole in the surface of the insulating layer (Z = 0 position in Fig. 2). The &quot; minimum diameter &quot; (D _min ) of the via hole refers to the minimum diameter of the via hole in the range of 0 to t. The &quot; _maximum diameter &quot; (D _max ) of the via-hole refers to the _maximum diameter of the via-hole in the range of 0 to t. For example, the via-hole in Fig. 2 (a) has a net taper shape in which the diameter gradually decreases from the insulating layer surface to the depth direction Z of the insulating layer. In this via-hole a, the aperture diameter D is the _maximum diameter D _max and the minimum diameter D _min at the via hole bottom portion (Z = t in Fig. 2). When a via hole is formed using a UV solid laser, a via hole of (a) is generally formed. In addition, the via holes shown in Fig. 2 (b) or (c) may be formed. (b) of the via hole, isolated a predetermined distance in the depth direction (Z) of the insulation layer from the layer surface, the diameter while the progress slowly (k ₁ t end, k ₁ is the number that satisfies 0 <k _{1 <1)} And the diameter gradually increases as it goes further in the depth direction. In this via-hole (b), the diameter of the aperture diameter D or the bottom of the via hole (Z = t) is the _maximum diameter (D _max ) and the minimum diameter D _min at the position of the depth (k ₁ t) . the diameter of the via hole of the insulating layer (c) gradually increases from a surface of the insulating layer in the depth direction Z of the insulating layer (k2t (k2 is a number satisfying 0 <k2 <1) The diameter gradually decreases in the depth direction. These via holes (c) the depth choedaegyeong the position of the _{(k 2 t) (D max} ) to indicate, opening diameter (D) or via diameter to a minimum diameter of (the position of Z = t) hole bottom portion (D _min) to be.

(a) - regardless of the via-hole in the distinction of (c), from the viewpoint of obtaining good electrical conduction to the reliability, of the via-hole opening diameter (D) and the via-hole in the minimum diameter (D _min) satisfies 0.65≤D _min / D Suitable. If the value of D _min / D is low, it results in deterioration of the penetration of the plating liquid into the via-hole, resulting in deterioration of the conduction reliability. From the viewpoint of obtaining better conduction reliability, the value of _Dmin / D is preferably 0.66 or more, more preferably 0.68 or more, more preferably 0.70 or more, 0.72 or more, 0.74 or more, 0.75 or more, 0.76 or more, or 0.77 Or more. The upper limit of the value of _Dmin / D is 1, and is usually 0.99 or less, 0.98 or less, 0.95 or less, 0.90 or less, and the like. According to the method of the present invention, it is possible to advantageously form a via-hole with a small diameter having a high value of D _min / D. The value of D _min / D can be determined by observing the surface by the via-hole opening on the SEM for a via-hole of a sufficient number (N _2). (d _min ) can be measured by the surface observation by the SEM when the diameter of the via hole bottom is smaller than the diameter D of the via hole in the via hole (c) When the diameter is not visible, the aperture diameter D is the minimum diameter (D _min )). N ₂ is preferably 10 or more.

In this case, it is preferable that the opening diameter D of the via-hole and the _maximum diameter D _max of the via-hole satisfy D _max / D? 1.35. The value of _Dmax / D is preferably 1.30 or less, more preferably 1.20 or less, still more preferably 1.10 or less, or 1.05 or less. The lower limit of the value of D _max / D is 1. D value of the _max / D can be determined by observation with respect to the via hole of a sufficient number (N _2), by a via hole section in the SEM. N ₂ is preferably 10 or more.

In the present invention, it is preferable that the thickness t (占 퐉) of the insulating layer and the opening diameter D (占 퐉) of the via hole satisfy t? 3D from the viewpoint of forming a via- More preferably satisfies t? 2D, more preferably satisfies t? 2D, more preferably satisfies t? 1.8D, t? 1.6D, t? 1.4D, or t? 1.2D desirable. The lower limit of the thickness t of the insulating layer is not particularly limited, but is usually 1 占 퐉 or more, 2 占 퐉 or more, 3 占 퐉 or more, and the like.

In a preferred embodiment, the insulating layer is formed by thermally curing a resin composition layer containing an inorganic filler.

The content of the inorganic filler in the resin composition constituting the resin composition layer is preferably 20% by mass or more, and more preferably 25% by mass or more from the viewpoint of sufficiently lowering the dielectric constant of the insulating layer and achieving high-speed signal transmission.

In the present invention, the content of each component constituting the resin composition is a value when the nonvolatile component in the resin composition is taken as 100% by mass.

When the insulating layer is formed using the resin composition containing the inorganic filler, the laser processability by the UV solid laser may be lowered and the via shape may be deteriorated. On the other hand, in the present invention, in which via holes are formed by a UV solid laser while satisfying the above-mentioned specific conditions (i) and (ii), a resin composition having a high inorganic filler content can be used without a problem of a via shape. For example, the content of the inorganic filler in the resin composition may be increased to 30 mass% or more, 40 mass% or more, 50 mass% or more, 60 mass% or more, or 70 mass% or more.

The upper limit of the content of the inorganic filler in the resin composition is preferably 90% by mass or less, more preferably 85% by mass or less, from the viewpoint of preventing the mechanical strength of the insulating layer from lowering.

The average particle diameter of the inorganic filler is preferably 0.2 占 퐉 or less, more preferably 0.15 占 퐉 or less, and even more preferably 0.1 占 퐉 or less, from the viewpoint of suitably satisfying the above conditions (i) and (ii). The lower limit of the average particle diameter of the inorganic filler is not particularly limited, but may be usually 0.01 탆 or more, 0.02 탆 or more, and the like. Examples of commercially available inorganic fillers having such an average particle diameter include "UFP-30" manufactured by Denki Kagaku Kogyo Co., Ltd., "YC100C" manufactured by Adomatech Co., Ltd., and "YA050C-MJE" have. The average particle diameter of the inorganic filler can be measured by a laser diffraction / scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be measured with a laser diffraction scattering type particle size distribution measuring apparatus, and the median diameter is determined as the average particle diameter. The sample to be measured may preferably be an inorganic filler dispersed in water by ultrasonic waves. As the laser diffraction scattering type particle size distribution measuring apparatus, "LA-500" manufactured by Horiba Seisakusho Co., Ltd. and the like can be used.

The BET specific surface area of the inorganic filler from the viewpoint of suitably satisfying the above conditions (i) and (ii), preferably at least 20m ² / g, more preferably 25m ² / g or more, more preferably 30m ² / g or more. The upper limit is not particularly limited, but is preferably 500 m ² / g or less, more preferably 400 m ² / g or less, and still more preferably 300 m ² / g or less. The BET specific surface area (m ² / g) of the inorganic filler can be measured as follows. Specifically, the specific surface area of the inorganic filler sample can be determined from the adsorption amount of an inorganic filler sample by adsorbing a molecule whose adsorption occupying area is known at a temperature of liquid nitrogen. An inert gas such as nitrogen or helium is suitably used as a molecule whose adsorption occupying area is known. The specific surface area S (m ² / g) of the inorganic filler can be measured by using an automatic specific surface area measuring device. Examples of the automatic specific surface area measuring device include Macsorb HM- 1210 &quot;.

Examples of the inorganic filler include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, Aluminum, manganese nitride, aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, zirconium phosphate and zirconium tungstate. Of these, silica such as amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica and the like is particularly suitable. As the silica, spherical silica is preferable. The inorganic fillers may be used singly or in combination of two or more kinds.

The inorganic filler is preferably treated with at least one surface treating agent such as a silane compound, an organosilazane compound, an aluminum-based coupling agent, a titanium-based coupling agent, and a zirconium-based coupling agent for improving moisture resistance.

In particular, by using an inorganic filler surface-treated with a silane compound containing an organic group having an aromatic ring, the value of A ₂ / (A ₁ + A ₂ ) is high and the value of n ² of the condition (ii) , An insulating layer can be realized. Accordingly, in a preferred embodiment, the resin composition constituting the resin composition layer, and further the insulating layer, contains an inorganic filler surface-treated with a silane compound containing an organic group having an aromatic ring.

From the viewpoint of realizing an insulating layer having a high value of A ₂ / (A ₁ + A ₂ ) and a low n ² , the organic group having an aromatic ring has 6 to 20 carbon atoms (preferably 6 to 14, More preferably 6 to 12, still more preferably 6 to 10) aryl groups are preferable, and among these, a phenyl group is preferable.

The silane compound containing an organic group having an aromatic ring used in the treatment of the inorganic filler is not particularly limited as long as it can introduce the organic group having an aromatic ring into the surface of the inorganic filler and includes a resin component such as an epoxy resin (For example, an amino group, an epoxy group, a mercapto group and the like) capable of reacting with a hydroxyl group. Specific examples of such silane compounds include phenyltrimethoxysilane, diphenyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, glycidoxypropylphenyldiethoxysilane, and mercaptopropyldimethoxysilane. . Examples of commercially available silane compounds include "KBM103" (phenyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (manufactured by Shin-Etsu Chemical Co., Methoxysilane), and the like. The silane compounds may be used alone, or two or more silane compounds may be used in combination.

The degree of surface treatment by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. The amount of carbon per unit surface area of the inorganic filler is preferably not less than 0.02 mg / m ² from the viewpoint of realizing an insulating layer having a high value of A ₂ / (A ₁ + A ₂ ) and a low n ² , / m &lt; ² &gt; is more preferable, and 0.2 mg / m &lt; ² &gt; or more is more preferable. On the other hand, from the viewpoint of preventing a rise in the melt viscosity of the melt viscosity of the resin varnish or film form, 1mg / m ² or less are preferred, 0.8mg / m ² or less, more preferably, 0.5mg / m ² or less, more desirable.

The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to an inorganic filler surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25 캜 for 5 minutes. After the supernatant is removed and the solids are dried, the amount of carbon per unit surface area of the inorganic filler can be measured using a carbon analyzer. As the carbon analyzer, "EMIA-320V" manufactured by Horiba Seisakusho Co., Ltd. and the like can be used.

In one embodiment, the resin composition constituting the resin composition layer includes a thermosetting resin in addition to the inorganic filler. As the thermosetting resin, conventionally known thermosetting resins used for forming the insulating layer of the circuit board can be used, and among them, an epoxy resin is preferable. The resin composition constituting the resin composition layer may also contain a curing agent. Accordingly, in one embodiment, the resin composition includes an epoxy resin and a curing agent in addition to the inorganic filler.

- Epoxy resin -

Examples of the epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol AF epoxy resin, dicyclopentadiene epoxy resin, trisphenol epoxy resin, naphthol novolak type epoxy resin, Epoxy resin, phenol novolak type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, Cresol novolak type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spirocyclic epoxy resins, cyclohexanedimethanol type epoxy resins, Tylene ether type epoxy resin, trimethylol type epoxy resin, tetraphenyl ethane type epoxy resin It can be given. The epoxy resins may be used alone or in combination of two or more.

The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. It is preferable that at least 50 mass% or more of the epoxy resin is an epoxy resin having two or more epoxy groups in one molecule, when the nonvolatile component of the epoxy resin is 100 mass%. Among them, the resin composition is preferably a solid epoxy resin (also referred to as &quot; solid epoxy resin &quot;) at a temperature of 20 占 폚 alone or in combination with a solid epoxy resin and a liquid epoxy resin ) In combination. As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in a molecule is preferable, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferable. The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule and more preferably an aromatic liquid epoxy resin having two or more epoxy groups in one molecule. In the present invention, an aromatic epoxy resin means an epoxy resin having an aromatic ring in its molecule.

Examples of the liquid epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenol novolak type epoxy resin, A cyclohexanedimethanol type epoxy resin, a glycidylamine type epoxy resin, and an epoxy resin having a butadiene structure are preferable, and a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a naphthalene Type epoxy resin is more preferable. Specific examples of the liquid epoxy resin include "HP4032", "HP4032H", "HP4032D", "HP4032SS" (naphthalene type epoxy resin), "jER828EL" and "828US" manufactured by Mitsubishi Kagaku Co., (Bisphenol A type epoxy resin), "jER807" (bisphenol F type epoxy resin), "jER152" (phenol novolak type epoxy resin), "ZX1059" (bisphenol A type epoxy resin EX-721 &quot; (glycidyl ester type epoxy resin) manufactured by Nagase Chemtex Co., Ltd., &quot; Celloxide 2021P &quot; manufactured by Daicel Co., Ltd. (a mixture of bisphenol F type epoxy resin (Cycloaliphatic epoxy resin) and &quot; PB-3600 &quot; (epoxy resin having a butadiene structure). These may be used alone, or two or more kinds may be used in combination.

Examples of the solid epoxy resin include naphthalene type tetrafunctional epoxy resin, cresol novolak type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, An anthracene type epoxy resin, a bisphenol A type epoxy resin, a bisphenol AF type epoxy resin and a tetraphenyl ethane type epoxy resin are preferable, and a naphthalene type tetrafunctional epoxy resin, a naphthol type epoxy resin, a biphenyl type epoxy resin, a dicyclopentadiene type An epoxy resin, and a bisphenol AF type epoxy resin are more preferable. Specific examples of the solid epoxy resin include "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin), "N-690", "N-695" (cresol novolac epoxy EXA7311-G3 "," EXA7311-G4 "," EXA7311-G4S "," HP6000 "," HP7200H "(dicyclopentadiene type epoxy resin) (Naphthylene ether type epoxy resin), "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (naphthol novolak type epoxy resin), "NC3000H", "NC3000" manufactured by Nippon Kayaku Co., , "NC3000L", "NC3100" (biphenyl type epoxy resin), "ESN475V" (naphthol type epoxy resin), "ESN485" (naphthol novolak type epoxy resin) manufactured by Shin- YX4000H "," YL6121 "(biphenyl type epoxy resin)," YX4000HK "(biquileneol type epoxy resin," YX8800 "(an anthracene type epoxy resin "PG-100", "CG-500" manufactured by Osaka Gas Chemical Co., Ltd., "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Kagaku Co., , "YER772" (bisphenol AF type epoxy resin), "jER1031S" (tetraphenyl ethane type epoxy resin), etc. These can be used alone or in combination of two or more. Or two or more of them may be used in combination.

When a liquid epoxy resin and a solid epoxy resin are used together as the epoxy resin, the ratio thereof (liquid epoxy resin: solid epoxy resin) is preferably in the range of 1: 0.1 to 1: 5 in mass ratio. By setting the proportions of the liquid epoxy resin and the solid epoxy resin in this range, suitable adhesiveness is obtained when i) used in the form of an adhesive film to be described later, and ii) sufficient flexibility is obtained when used in the form of an adhesive film , Handling property is improved, and (iii) a cured product having sufficient breaking strength can be obtained. In view of the effects of i) to iii), the ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is more preferably in the range of 1: 0.5 to 1: 5, To 1: 4.5, more preferably in the range of 1: 1.5 to 1: 4.5.

The content of the epoxy resin in the resin composition is preferably 3% by mass to 60% by mass, more preferably 5% by mass to 55% by mass, and still more preferably 5% by mass to 45% by mass.

The epoxy equivalent of the epoxy resin is preferably 50 to 5000, more preferably 50 to 3000, still more preferably 80 to 2000, still more preferably 110 to 1000. With this range, the cross-linking density of the cured product becomes sufficient, resulting in an insulating layer having a small surface roughness. The epoxy equivalent can be measured in accordance with JIS K7236, and is the mass of the resin containing one equivalent of epoxy group.

The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and still more preferably 400 to 1500. Here, the weight average molecular weight of the epoxy resin is a weight average molecular weight in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

- hardener -

The curing agent is not particularly limited as long as it has a function of curing an epoxy resin, and examples thereof include phenol-based curing agents, naphthol-based curing agents, active ester-based curing agents, benzoxazine- based curing agents, cyanate ester- based curing agents and carbodiimide- And a hardening agent. The curing agent may be used alone or in combination of two or more.

As the phenol-based curing agent and naphthol-based curing agent, a phenol-based curing agent having a novolak structure or a naphthol-based curing agent having a novolak structure is preferable from the viewpoints of heat resistance and water resistance. From the viewpoint of adhesion strength with the conductor layer, a nitrogen-containing phenol-based curing agent or a nitrogen-containing naphthol-based curing agent is preferable, and a phenol-based curing agent containing a triazine structure or a naphthol-based curing agent containing a triazine structure is more preferable. Of these, a phenazine novolac resin containing a triazine structure or a naphthol novolak resin containing a triazine structure is preferable from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion strength with a conductor layer. These may be used alone, or two or more kinds may be used in combination.

Specific examples of the phenol-based curing agent and naphthol-based curing agent include "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Meiwa Kasei Co., SN-170 "," SN-180 "," SN-190 "," SN-475 "and" SN-485 "manufactured by Shinnitetsu Sumikin Kagaku Co., LA-7054 "," LA-3018 "," LA-1356 "," SN-395 " , &Quot; TD2090 &quot;, &quot; LA-3018-50P &quot;, and the like.

The active ester-based curing agent is not particularly limited, but generally includes ester groups having a high reaction activity, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds, Is preferably used. It is preferable that the active ester-based curing agent is obtained by a condensation reaction of a carboxylic acid compound and / or a thiocarboxylic acid compound with a hydroxy compound and / or a thiol compound. From the viewpoint of heat resistance improvement, an active ester type curing agent obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester type curing agent obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is more preferable. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid and pyromellitic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, phenol phthaline, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o- , p-cresol, catechol, alpha -naphthol, beta -naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, tri Hydroxybenzophenone, tetrahydroxybenzophenone, fluoroglucine, benzenetriol, dicyclopentadiene type diphenol compounds, phenol novolak, and the like. Here, the "dicyclopentadiene type diphenol compound" refers to a diphenol compound obtained by condensing two molecules of phenol in one molecule of dicyclopentadiene.

Specific examples of suitable active ester curing agents include active ester compounds containing a dicyclopentadiene type diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing an acetylated phenol novolac, An active ester compound containing a benzoylate, and an active ester compound obtained by reacting an aromatic carboxylic acid with a phosphorus atom-containing oligomer having a phenolic hydroxyl group. Of these, an active ester compound having a dicyclopentadiene type diphenol structure , An active ester compound containing a naphthalene structure, and an active ester compound obtained by reacting an aromatic carboxylic acid with a phosphorus atom-containing oligomer having a phenolic hydroxyl group. In the present invention, the "dicyclopentadiene type diphenol structure" refers to a divalent structural unit comprising phenylene-dicyclopentylene-phenylene.

As the active ester type curing agent, the active ester compounds disclosed in Japanese Patent Application Laid-Open Nos. 2004-277460 and 2013-40270 may be used, or commercially available active ester compounds may be used. EXB9451 "," EXB9460 "," EXB9460S "," HPC-8000-65T "," HPC-8000L-65M "(dicyclopentadiene type (Active ester compound containing diphenol structure), "9416-70BK" (active ester compound containing naphthalene structure) manufactured by DIC Corporation, "DC808" (acetyl compound of phenol novolac manufactured by Mitsubishi Chemical Corporation) (Active ester compound containing cargo), YLH1026 (active ester compound containing phenol novolak benzoylate) manufactured by Mitsubishi Kagaku Co., Ltd., EXB9050L-62M (phosphorus atom containing compound Active ester compounds).

Specific examples of the benzoxazine type curing agent include "HFB2006M" manufactured by Showa Kobunshi Co., Ltd., "P-d" and "F-a" manufactured by Shikoku Kasei Kogyo Co.,

The cyanate ester-based curing agent is not particularly limited, and examples thereof include cyanate ester-based curing agents such as novolac type (phenol novolac type, alkylphenol novolac type and the like), dicyclopentadiene type cyanate ester type curing agents, (Bisphenol A type, bisphenol F type, bisphenol S type, etc.) cyanate ester type curing agents, and partially triarylated prepolymers thereof. Specific examples thereof include bisphenol A dicyanate, polyphenol cyanate (oligo (3-methylene-1,5-phenylene cyanate)), 4,4'-methylene bis (2,6-dimethylphenyl cyanate) , 4'-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanate phenylmethane) (4-cyanate-3,5-dimethylphenyl) methane, 1,3-bis (4-cyanate phenyl- 1- (methyl ethylidene)) benzene, bis Bifunctional cyanate resins such as bis (4-cyanate phenyl) ether, polyfunctional cyanate resins derived from phenol novolak and cresol novolak, and prepolymers in which some of these cyanate resins are triarized . Examples of commercially available cyanate ester curing agents include "PT30" and "PT60" (both phenol novolac type polyfunctional cyanate ester resins) manufactured by Lone Japan Co., Ltd., "BA230" (bisphenol A dicyanate A prepolymer in which a part or all of the polymer is trimerized to form a trimer).

Specific examples of the carbodiimide-based curing agent include "V-03" and "V-07" manufactured by Nisshinbo Chemical Co.,

The ratio of the amount of the epoxy resin to the amount of the curing agent is preferably from 1: 0.2 to 1: 2 in terms of the ratio of [the total number of epoxy groups of epoxy resin]: [the total number of reactors of the curing agent] from the viewpoint of improving the mechanical strength and water resistance of the obtained insulating layer , More preferably in the range of 1: 0.3 to 1: 1.5, and further preferably in the range of 1: 0.4 to 1: 1.2. Here, the reactive group of the curing agent is an active hydroxyl group, an active ester group or the like, and varies depending on the kind of the curing agent. The total number of epoxy groups of the epoxy resin means the value obtained by dividing the solid mass of each epoxy resin by the epoxy equivalent, and the total number of reactors of the curing agent means the total of the solid mass of each curing agent Divided by the total amount of the curing agent.

The resin composition may further contain at least one additive selected from the group consisting of a thermoplastic resin, a curing accelerator, a flame retardant and an organic filler, if necessary.

- Thermoplastic resin -

Examples of the thermoplastic resin include thermoplastic resins such as phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyether sulfone resin, Ether resins, polycarbonate resins, polyetheretherketone resins, and polyester resins. The thermoplastic resins may be used alone or in combination of two or more.

The weight average molecular weight of the thermoplastic resin in terms of polystyrene is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and still more preferably in the range of 20,000 to 60,000. The weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured by gel permeation chromatography (GPC). Specifically, the weight average molecular weight of the thermoplastic resin in terms of polystyrene was measured using LC-9A / RID-6A manufactured by Shimadzu Corporation, Shodex K-800P / K manufactured by Showa Denko K.K. -804L / K-804L can be measured using a calibration curve of standard polystyrene at a column temperature of 40 DEG C using chloroform or the like as the mobile phase.

Examples of the phenoxy resin include bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, A phenoxy resin having at least one skeleton selected from the group consisting of a skeleton, an anthracene skeleton, an adamantane skeleton, a terpene skeleton, and a trimethyl cyclohexane skeleton. The terminal of the phenoxy resin may be any functional group of a phenolic hydroxyl group, an epoxy group and the like. The phenoxy resins may be used alone or in combination of two or more. Specific examples of the phenoxy resin include "1256" and "4250" (both phenol resins containing a bisphenol A skeleton), "YX8100" (phenoxy resin containing a bisphenol S skeleton) and "YX6954" manufactured by Mitsubishi Kagaku Co., (Phenoxy resin containing a bisphenol acetophenone skeleton). In addition, "FX280" and "FX293" manufactured by Shin Nitetsu Sumikin Kagaku Co., Ltd., "YX7553BH30" and "YX7553" manufactured by Mitsubishi Kagaku Co., , "YL6794", "YL7213", "YL7290", and "YL7482".

Specific examples of the polyvinyl acetal resin include a polyvinyl formal resin and a polyvinyl butyral resin, and a polyvinyl butyral resin is preferable. (Electrolytic Butyral 4000-2, 5000-A, 6000-C, 6000-EP manufactured by Denki Kagaku Kogyo K.K.), Sreek BH series, BX series, KS Series (specifically, &quot; KS-1 &quot;, etc.), BL series, BM series and the like.

Specific examples of the polyimide resin include "Rika coat SN-20" and "Rika coat PN-20" manufactured by Shin-Nihon Rika K.K. Specific examples of the polyimide resin include linear polyimide obtained by reacting a bifunctional hydroxyl-terminated polybutadiene, a diisocyanate compound and a tetrabasic acid anhydride (described in JP-A No. 2006-37083), a polysiloxane skeleton Modified polyimides such as polyimide containing polyimide (Japanese Patent Application Laid-Open No. 2002-12667 and Japanese Patent Application Laid-Open No. 2000-319386).

Specific examples of the polyamide-imide resin include "VYLOMAX HR11NN" and "VYLOMAX HR16NN" manufactured by Toyo Boseki K.K. Specific examples of the polyamide-imide resin include modified polyamideimide such as polyamideimide "KS9100" and "KS9300" containing a polysiloxane skeleton manufactured by Hitachi Chemical Co., Ltd.

Specific examples of the polyether sulfone resin include "PES 5003P" manufactured by Sumitomo Chemical Co., Ltd.

Specific examples of the polysulfone resin include polysulfone "P1700" and "P3500" manufactured by Solvay Advanced Polymers Co., Ltd.

The content of the thermoplastic resin in the resin composition is preferably 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, and still more preferably 1% by mass to 5% by mass.

- Curing accelerator -

Examples of the curing accelerator include phosphorus hardening accelerators, amine hardening accelerators (for example, 4-dimethylaminopyridine), imidazole hardening accelerators, guanidine hardening accelerators and metal hardening accelerators. Phosphorus hardening accelerators , An amine-based curing accelerator, and an imidazole-based curing accelerator. The curing accelerator may be used singly or in combination of two or more. The content of the curing accelerator in the resin composition layer is preferably in the range of 0.05 mass% to 3 mass%, assuming that the total of the nonvolatile components of the epoxy resin and the curing agent is 100 mass%.

- Flame retardant -

Examples of the flame retardant include organic phosphorus flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, silicon-based flame retardants and metal hydroxides. The flame retardant may be used alone, or two or more thereof may be used in combination. The content of the flame retardant in the resin composition is not particularly limited, but is preferably 0.5% by mass to 10% by mass, and more preferably 1% by mass to 9% by mass. As the flame retardant, for example, "HCA-HQ" manufactured by Sanko Co., Ltd. can be used.

- Organic filler -

As the organic filler, any organic filler that can be used in forming the insulating layer of the printed wiring board may be used, and examples thereof include rubber particles, polyamide fine particles, and silicone particles, and rubber particles are preferable .

The rubber particles are not particularly limited as long as they are fine particles of a resin which is chemically crosslinked to a rubber-elastic resin and is insoluble in an organic solvent and made to be unfused. For example, acrylonitrile-butadiene Rubber particles, butadiene rubber particles, acrylic rubber particles and the like. Specific examples of the rubber particles include XER-9l (manufactured by Nihon Kogyo Seiyaku Co., Ltd.), styrophyloids AC3355, AC3816, AC3816N, AC3832, AC4030, AC3364, IMl01 (manufactured by Aika Kogyo Co., Ltd.) Paraloid EXL2655, EXL2602 Or more, manufactured by Kureha Chemical Industry Co., Ltd.).

The average particle diameter of the organic filler is preferably in the range of 0.005 탆 to 1 탆, more preferably in the range of 0.2 탆 to 0.6 탆. The average particle diameter of the organic filler can be measured using a dynamic light scattering method. For example, an organic filler is uniformly dispersed in an appropriate organic solvent by ultrasonic waves or the like, and the particle size of the organic filler is measured by using a dense system particle diameter analyzer (FPAR-1000 manufactured by Otsuka Denshi Co., Ltd.) The distribution can be measured on the basis of mass, and the median diameter can be measured as the average particle diameter. The content of the organic filler in the resin composition is preferably 1% by mass to 10% by mass, and more preferably 2% by mass to 5% by mass.

- Other ingredients -

The resin composition may contain other components as required. Examples of such other components include organometallic compounds such as organic copper compounds, organic zinc compounds and organic cobalt compounds, and resin additives such as thickeners, defoaming agents, leveling agents, adhesion-imparting agents, and coloring agents.

The method of preparing the resin composition is not particularly limited, and examples thereof include a method of mixing and dispersing the compounding ingredients, if necessary, with a solvent, etc., using a rotary mixer or the like. Further, from the viewpoint of setting the n ² in the condition (ii) to 0.2 탆 or less, the resin composition may be filtered to remove particles having a predetermined particle diameter, if necessary. Therefore, in one embodiment, the insulating layer is formed by thermally curing a layer of the resin composition subjected to treatment for removing particles having a particle diameter (d) (탆) or more by filter filtration. Here, d is preferably 4 or less, more preferably 3 or less, more preferably 2 or less, still more preferably 1 or less. The filtration accuracy of the filter is preferably 4 탆 or less, more preferably 3 탆 or less, further preferably 2 탆 or less, and still more preferably 1 탆 or less. Suitable filters that can be used for filtering the resin composition include, for example, "SCP-010", "SHP-020" and "SHP-030" manufactured by Rocky Technology Corporation.

[Circuit board]

A circuit board obtained on the basis of the above-described concept of the present invention will be described.

The circuit board of the present invention is a circuit board comprising an insulating layer having a via-hole having an opening diameter of 15 탆 or less,

The arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less,

In the case where the insulating layer contains an inorganic filler and the average value of the maximum diameters of the inorganic fillers contained in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is n ¹ , and a value (n ² ) of n ¹ × 1.27 is 0.2 μm or less.

The circuit board of the present invention is characterized in that a via-hole having a small diameter and a small diameter is formed in an insulating layer containing an inorganic filler.

(A suitable range of D _min / D and D _max / D), a suitable Ra value of the insulating layer surface, a thickness of the insulating layer, n ² and A ₂ / (A ₁ + A &lt; ₂ &gt;) is as described above. The composition of the insulating layer is also as described above. In a preferred embodiment, the insulating layer comprises an inorganic filler surface-treated with a silane compound comprising an organic group having an aromatic ring. Details of the organic group having an aromatic ring, suitable silane compounds are as described above.

The circuit board of the present invention further includes a conductor layer (circuit) formed on the surface of the insulating layer. Details of the conductor layer are as described in [Method for producing circuit board] described later. In a preferred embodiment, the circuit board of the present invention has a ratio L / S of a circuit width (line L) to a circuit width (space S) of 10 mu m / 10 mu m or less (i.e., Or less). L / S = 8 占 퐉 / 8 占 퐉 or less (wiring pitch: 16 占 퐉 or less), L / S = 7 占 퐉 L / S = 5 占 퐉 / 5 占 퐉 or less (wiring pitch: 10 占 퐉 or less), or L / S = 4 占 퐉 / 4 占 퐉 or less (wiring pitch: 8 占 퐉 or less).

[Semiconductor device]

A semiconductor device can be manufactured using the circuit board of the present invention.

Examples of the semiconductor device include various semiconductor devices provided in an electric product (such as a computer, a mobile phone, a digital camera and a television) and a vehicle (such as a motorcycle, a car, a train, have.

The semiconductor device of the present invention can be manufactured by mounting a component (semiconductor chip) in a conductive portion of a circuit board. The &quot; conduction site &quot; is a &quot; location where electric signals are transmitted on the circuit board &quot;, and the location may be either a surface or a buried site. The semiconductor chip is not particularly limited as long as it is an electric circuit element made of a semiconductor material.

The method for mounting the semiconductor chip in manufacturing the semiconductor device of the present invention is not particularly limited as long as the semiconductor chip can function effectively. Specifically, the method can be applied to a wire bonding mounting method, a flip chip mounting method, a bump- A mounting method using an anisotropic conductive film (ACF), a mounting method using a non-conductive film (NCF), and the like. Here, the &quot; mounting method using the bumpless buildup layer (BBUL) &quot; is a mounting method in which &quot; the semiconductor chip is directly buried in the concave portion of the printed wiring board and the semiconductor chip is connected to the wiring on the circuit board &quot;.

[Method of manufacturing circuit board]

The method for producing a circuit board of the present invention is not particularly limited as long as the above-described concept of the present invention can be achieved. Best Mode for Carrying Out the Invention Hereinafter, a preferred embodiment capable of achieving the concept of the present invention will be described.

&Lt; First Embodiment >

A method of manufacturing a circuit board according to the present invention includes:

(A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 탆 or less in the insulating layer by a UV solid laser,

Wherein the insulating layer formed in the step (B) includes an inorganic filler and an average value of a maximum diameter of the inorganic filler contained in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is n ¹ (Μm), the value (n ² ) of n ¹ × 1.27 is 0.2 μm or less.

- Process (A) -

In the step (A), an adhesive film comprising a support and a resin composition layer provided on the support is laminated on the inner layer substrate such that the resin composition layer is bonded to the inner layer substrate.

The resin composition constituting the resin composition layer is as described above. The thickness of the resin composition layer is not particularly limited as long as the thickness (t) (mu m) of the obtained insulating layer satisfies the above specific relationship (i.e., t 3D) between the diameter D of the via- But may be determined appropriately.

As the support, for example, a film made of a plastic material, a metal foil and a release paper can be mentioned, and a film or a metal foil made of a plastic material is preferable.

When a film made of a plastic material is used as the support, examples of the plastic material include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate (PC), polymethyl methacrylate ), Acrylic, cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide and the like. Of these, polyethylene terephthalate and polyethylene naphthalate are preferable, and inexpensive polyethylene terephthalate is particularly preferable. As the polyethylene terephthalate, a commercially available product may be used. For example, &quot; Lumirror T6AM &quot; manufactured by Toray Industries, Inc. may be used.

When a metal foil is used as a support, examples of the metal foil include copper foil and aluminum foil, and copper foil is preferable. As the copper foil, a foil made of a single metal of copper may be used, or a foil made of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) .

The support may be subjected to a mat treatment or a corona treatment on the surface of the support on the side of bonding with the resin composition layer. As the support, a release layer-adhered support having a release layer on the surface of the side bonded to the resin composition layer may be used. Examples of the release agent used for the release layer of the release layer-adhered support include at least one release agent selected from the group consisting of an alkyd resin, an olefin resin, a urethane resin, and a silicone resin. Commercially available products of the release agent include, for example, "SK-1", "AL-5", and "AL-7" manufactured by Lintec Corporation, which are alkyd resin type mold release agents.

The arithmetic mean roughness (Ra) of the surface of the support on the side bonded to the resin composition layer is preferably 150 nm or less, preferably 140 nm or less, more preferably 150 nm or less from the viewpoint of lowering the Ra value of the surface of the insulating layer formed in the step (B) Preferably 130 nm or less, more preferably 120 nm or less, still more preferably 110 nm or less, particularly preferably 100 nm or less, 90 nm or less, 80 nm or less, or 70 nm or less. The lower limit of the Ra is not particularly limited, but may be usually 1 nm or more, 5 nm or more, 10 nm or more from the viewpoint of obtaining an insulating layer having good adhesion strength with the conductor layer. The arithmetic mean roughness (Ra) of the surface of the support on the side to be bonded to the resin composition layer can be measured by the same method as described for Ra on the surface of the insulating layer.

The thickness of the support is not particularly limited, but is preferably 75 占 퐉 or less, more preferably 60 占 퐉 or less, 50 占 퐉 or less, or 40 占 퐉 or less. The lower limit of the thickness of the support is not particularly limited, but may be usually 1 占 퐉 or more, 2 占 퐉 or more, 5 占 퐉 or more, or the like. When the support is a release layer-adhered support, it is preferable that the thickness of the entirety of the release layer-adhered support is in the above range.

The adhesive film can be produced, for example, by preparing a resin varnish obtained by dissolving a resin composition in an organic solvent, applying the resin varnish on a support using a die coater or the like, and drying the resin varnish to form a resin composition layer.

Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone (MEK) and cyclohexanone, acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate, And aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone; and solvent naphtha . The organic solvents may be used alone, or two or more kinds may be used in combination.

The drying may be carried out by a known method such as heating, hot wind blowing and the like. The drying conditions are not particularly limited, but the drying is performed so that the content of the organic solvent in the resin composition layer is 10 mass% or less, preferably 5 mass% or less. For example, 30 to 60% by mass, is used, the resin varnish is dried at 50 to 150 DEG C for 3 minutes to 10 minutes to form a resin composition layer Can be formed.

In the adhesive film, a protective film can be further laminated on the surface of the resin composition layer not bonded to the support (that is, the surface opposite to the support). The thickness of the protective film is not particularly limited, but is, for example, 1 m to 40 m. By laminating a protective film, it is possible to prevent adhesion and scratches of dust or the like to the surface of the resin composition layer. The adhesive film can be rolled and stored. When the adhesive film has a protective film, it can be used by peeling the protective film.

The term "inner layer substrate" used in the step (A) means a substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, Refers to a circuit board on which conductor layers (circuits) patterned on both sides are formed. Further, when the circuit board is manufactured, the inner layer circuit board of the intermediate product in which the insulating layer and / or the conductor layer is to be formed is also included in the &quot; innerlayer board &quot; When the circuit board is a component internal circuit board, an inner-layer board containing components may be used.

The lamination of the inner layer substrate and the adhesive film can be carried out, for example, by thermally bonding an adhesive film to the inner layer substrate from the support side. Examples of the member for heating and pressing the adhesive film to the inner layer substrate (hereinafter also referred to as "hot pressing member") include a heated metal plate (SUS hard plate) or a metal roll (SUS roll). It is also preferable to press the hot pressing member through an elastic material such as heat-resistant rubber so that the adhesive film is sufficiently followed on the surface unevenness of the inner layer substrate, not directly on the adhesive film.

The lamination of the inner layer substrate and the adhesive film may be performed by a vacuum lamination method. In the vacuum laminating method, the heat pressing temperature is preferably in the range of 60 占 폚 to 160 占 폚, more preferably 80 占 폚 to 140 占 폚, and the heat pressing pressure is preferably 0.098 MPa to 1.77 MPa, more preferably 0.29 MPa to 1.47 MPa, and the heat pressing time is preferably in a range of from 20 seconds to 400 seconds, more preferably from 30 seconds to 300 seconds. The lamination is preferably performed under a reduced pressure of 26.7 hPa or less.

The lamination can be carried out by a commercially available vacuum laminator. As a commercially available vacuum laminator, there can be mentioned, for example, vacuum pressurized laminator manufactured by Meishi Seisakusho Co., Ltd., and vacuum applicator manufactured by Nichigo Morton Co., Ltd.

After lamination, the laminated adhesive film may be subjected to a smoothing treatment under atmospheric pressure (at atmospheric pressure), for example, by pressing a hot press member from the support side. The pressing condition of the smoothing treatment can be set to the same conditions as the hot pressing conditions of the lamination. The smoothing treatment can be performed by a commercially available laminator. The lamination and the smoothing process may be continuously performed using the commercially available vacuum laminator.

- Process (B) -

In the step (B), the resin composition layer is thermally cured to form an insulating layer in the state that the support is attached.

The conditions of thermal curing are not particularly limited, and conditions that are generally employed when forming the insulating layer of the circuit board may be used.

The thermosetting condition of the resin composition layer varies depending on the composition of the resin composition used in the resin composition layer and the like, but is not particularly limited as long as a suitable insulating layer can be finally formed. For example, To 240 캜, more preferably in the range of 150 캜 to 210 캜, and further preferably in the range of 160 캜 to 190 캜. Here, the heat curing temperature does not necessarily have to be fixed to the predetermined temperature within the above-mentioned temperature range, but may be changed with time as long as a proper insulating layer is formed, or may be cured at different curing temperatures good. It is also preferable that the maximum attained temperature of the curing temperature is within the above range.

The thermosetting time differs depending on the composition of the resin composition used for the resin composition layer and the thermosetting temperature, but is not particularly limited as long as a suitable insulating layer is finally formed, and may be, for example, 20 minutes to 150 minutes, For 30 minutes to 120 minutes, more preferably for 40 minutes to 120 minutes.

The thermosetting of the resin composition layer is preferably carried out under atmospheric pressure (normal pressure).

As described above, in the present invention, the arithmetic mean roughness (Ra) of the surface of the insulating layer is 150 nm or less (condition (i)). When the Ra value exceeds 150 nm, there is a problem that the laser processability is lowered and the via shape is deteriorated. Generally, when an insulating layer is formed by thermosetting a resin composition, the inorganic filler is exposed on the surface of the insulating layer due to melting of the resin, or the surface smoothness is lowered, According to the method for producing a circuit board of the present invention for thermally curing a resin composition layer in a state where a support is attached to a composition layer, a low Ra value can be easily achieved. Further, it is effective to raise the temperature stepwise when thermosetting, because it makes the Ra value lower. For example, after heating for 10 minutes to 60 minutes at a heat curing temperature T1 (50 占 폚? T1 <150 占 폚), heating at a temperature T2 (150 占 폚? T2? 240 占 폚) Followed by heating for 90 minutes to effect thermal curing. A suitable range of the Ra value is as described above.

The insulating layer formed in the step (B) includes an inorganic filler, and the n ² in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is 0.2 탆 or less ii)). When n ² exceeds 0.2 탆, there is a problem that laser workability is lowered and the via shape is deteriorated. In general, n ² tends to increase when the content of the inorganic filler in the insulating layer is high. When degrade the n ^2, 1) having an average particle diameter of the use of small inorganic filler, and 2) the direction the treated surface with a silane compound containing an organic group having a ring using the inorganic filler, and 3) embodiment of a filter filtration of the resin composition, etc. Is valid. The suitable range of n ² is as described above.

The support may be removed after the step (B). In a preferred embodiment, the support is removed prior to step (C). When a metal foil which is extremely thin (for example, 2 mu m or less in thickness or 1 mu m or less in thickness) is used as the support, the step (C) may be carried out while the support is attached to the insulating layer.

- Process (C) -

In the step (C), a via hole having an opening diameter of 15 mu m or less is formed in the insulating layer by a UV solid laser.

Details of the UV solid laser (laser wavelength, etc.) and aperture diameter and shape of the via hole are as described above.

- Process (D) -

The method of manufacturing a circuit board of the present invention may further include (D) a step of performing a desmear treatment after the step (C).

According to the method of the present invention, it is possible to form a via-hole having a small diameter with a small amount of smear in the via-hole in the insulating layer including the inorganic filler (even when the content of the inorganic filler in the insulating layer is high). Therefore, in the method of the present invention, step (D) may or may not be carried out. Even when the step (D) is carried out, it can be carried out under mild conditions as compared with the normal desmear treatment. Therefore, it is possible to suppress the harmonization of the surface of the insulating layer by the desmearing process, and realize the insulating layer having a low surface roughness suitable for forming the fine wiring.

The desmear treatment is not particularly limited and can be carried out by various known methods. In one embodiment, the desmear treatment may be a wet desmear treatment using an oxidizing agent solution.

In the wet desmear treatment using the oxidizing agent solution, it is preferable to perform the swelling treatment with the swelling liquid, the oxidation treatment with the oxidizing agent solution, and the neutralization treatment with the neutralizing liquid in this order. The swelling liquid is not particularly limited, and examples thereof include an alkali solution and a surfactant solution. Preferably, the swelling liquid is an alkali solution. More preferably, the alkali solution is a sodium hydroxide solution or a potassium hydroxide solution. Examples of swelling solutions that are commercially available include Swelling Dip Sicergans P, Swelling Dip Sicuregans SBU manufactured by Atotech Japan Co., Ltd., and the like. The swelling treatment by the swelling liquid is not particularly limited, but can be carried out, for example, by immersing the swelling liquid at 30 캜 to 90 캜 for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin in the insulating layer to an appropriate level, it is preferable to immerse the cured body in a swelling liquid at 40 占 폚 to 80 占 폚 for 5 minutes to 15 minutes. The oxidizing agent solution is not particularly limited, and for example, an alkaline permanganic acid solution obtained by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide can be mentioned. The oxidation treatment with an oxidizing agent such as an alkaline permanganic acid solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60 占 폚 to 80 占 폚 for 10 minutes to 30 minutes. The concentration of the permanganate in the alkaline permanganic acid solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agent solutions include alkaline permanganic acid solutions such as "Concentrate Compact CP" and "Dozing Solution · Sekurigans P" manufactured by Atotech Japan Co., Ltd. An acidic aqueous solution is preferable as the neutralization solution, and commercially available products include, for example, "Reduction Solution · Sucuregent P" manufactured by Atotech Japan Co., Ltd. The treatment with the neutralizing liquid can be carried out by immersing the treated surface subjected to the roughening treatment with an oxidizing agent in a neutralizing solution at 30 ° C to 80 ° C for 5 minutes to 30 minutes. From the standpoint of workability and the like, it is preferable to immerse the object subjected to the roughening treatment with an oxidizing agent in a neutralizing solution at 40 DEG C to 70 DEG C for 5 minutes to 20 minutes.

- Process (E) -

The method of manufacturing a circuit board of the present invention may further include a step of forming a conductor layer on the surface of the insulating layer (E) after the step (C).

The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer comprises at least one metal selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. The conductor layer may be either a single metal layer or an alloy layer. Examples of the alloy layer include two or more kinds of metal alloys selected from the above group (for example, nickel-chromium alloy, copper-nickel alloy, Alloy). Among these, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or a nickel-chromium alloy, a copper-nickel alloy, An alloy layer of a copper-titanium alloy is preferable and a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper or an alloy layer of nickel-chromium alloy is more preferable, More preferable.

The conductor layer may have a single-layer structure or a multi-layer structure in which two or more single metal layers or alloy layers made of different kinds of metals or alloys are stacked. When the conductor layer is a multilayer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc or titanium, or an alloy layer of nickel-chromium alloy.

The thickness of the conductor layer depends on the design of the desired circuit board, but is usually 35 μm or less, preferably 30 μm or less, and more preferably 25 μm or less. The lower limit of the thickness of the conductor layer is not particularly limited, but is usually 3 占 퐉 or more, preferably 5 占 퐉 or more.

In the step (E), the conductor layer may be formed by dry plating, wet plating, or a combination thereof.

Examples of dry plating include physical vapor deposition (PVD) methods such as vapor deposition, sputtering, ion plating and laser ablation, chemical vapor deposition (CVD) methods such as thermal CVD and plasma CVD, , Sputtering is preferable. When the conductor layer is formed only by dry plating, a conductor layer (circuit) may be formed by a known method such as a pull-add method.

When the conductor layer is formed by wet plating, a conductor layer may be formed by a semiaderm method in combination of electroless plating and electrolytic plating, a plating resist having an inverse pattern to that of the conductor layer is formed, and electroless plating The conductor layer may be formed by a pull-add method. When an extremely thin metal foil is used as a support, a conductor layer may be formed by modified semiaddition method. These methods may be carried out according to a known procedure in the art.

The conductor layer may be formed by combining dry plating and wet plating. For example, a metal layer formed by dry plating can be used as a plating seed layer, and a conductor layer can be formed by a semiaderm method using electrolytic plating or electroless plating.

In the semi-additive method, an unnecessary plating seed layer is removed by etching or the like to form a conductor layer (circuit) having a desired wiring pattern. At this time, if the surface roughness of the insulating layer is large, it is difficult to remove the plating seed layer in the roughness region when removing the plating seed layer unnecessary for etching at the time of forming the wiring pattern, and the plating seed layer in the roughness region The dissolution of the wiring pattern becomes remarkable, and the circuit wiring becomes finer. On the other hand, in the method of the present invention, since the desmear treatment is unnecessary or can be carried out under mild conditions as described above, the insulating layer with low surface roughness can be realized. A via hole having a small diameter and a small diameter can be realized. In addition, the method of manufacturing a circuit board of the present invention significantly contributes both to higher density and finer circuit wiring.

&Lt; Second Embodiment >

A method of manufacturing a circuit board according to the present invention includes:

(A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,

Characterized in that the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having a BET specific surface area of 20 m ² / g or more.

The BET specific surface area and the preferred range of the content of the inorganic filler in the second embodiment are as described above.

The steps (A) to (C) of the second embodiment are the same as those described in the "step (A)" to the "step (C)" of the first embodiment. After the step (C), the step (D) and the step (E) may be further included. The steps (D) and (E) are the same as those described in the "step (D)" and the "step (E)" in the first embodiment.

&Lt; Third Embodiment >

A method of manufacturing a circuit board according to the present invention includes:

(A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;

(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And

(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,

Wherein the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having an average particle diameter of 0.2 占 퐉 or less.

The preferable range of the average particle diameter and content of the inorganic filler in the third embodiment is as described above.

The steps (A) to (C) of the third embodiment are the same as those described in the "step (A)" to the "step (C)" of the first embodiment. After the step (C), the step (D) and the step (E) may be further included. The steps (D) and (E) are the same as those described in the "step (D)" and the "step (E)" in the first embodiment.

Although the preferred embodiments of the method of manufacturing a circuit board of the present invention have been described above, the method of the present invention may include other steps as long as the concept of the present invention can be achieved.

[Example]

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the following description, &quot; part &quot; and &quot;% &quot; mean &quot; part by mass &quot; and &quot;% by mass &quot; respectively.

<Measurement and evaluation method>

First, the measurement and evaluation method in the physical property evaluation in the present specification will be described.

[Preparation of substrate for measurement and evaluation]

(1) ground treatment of inner layer circuit board

Both sides of a glass cloth-based epoxy resin double-sided copper clad laminate (copper foil thickness 18 占 퐉, substrate thickness 0.4 mm, "R1515A" manufactured by Panasonic Corporation) CZ8100 &quot;) to conduct roughening treatment of the copper surface.

(2) lamination of an adhesive film

Protective films were peeled off from the adhesive films produced in Examples and Comparative Examples. The exposed adhesive film of the resin composition layer was laminated so that the resin composition layer was bonded to the inner layer circuit board using a batch type vacuum pressure laminator (2 stage buildup laminator "CVP700" manufactured by Nichigo Moton Co., Ltd.) Respectively. The lamination was carried out by reducing the pressure for 30 seconds to bring the air pressure to 13 hPa or less, followed by compression at 100 DEG C and a pressure of 0.74 MPa for 30 seconds. Subsequently, the laminated adhesive film was hot pressed and smoothed at atmospheric pressure at 100 DEG C and a pressure of 0.5 MPa for 60 seconds.

(3) Curing of resin composition

After laminating the adhesive films, the resin composition layer was thermally cured to form an insulating layer on both surfaces of the inner-layer circuit board. At this time, the resin composition layer was thermally cured in the state that the support was adhered, and after the curing, the support was peeled off. The resulting substrate is referred to as &quot; evaluation substrate (a) &quot;.

The thermosetting of the resin composition layer was performed at 100 캜 for 30 minutes (after being put into an oven at 100 캜) and then for 30 minutes at 170 캜 (after being transferred to the oven at 170 캜). Thereafter, the substrate was taken out under a room temperature atmosphere.

(4) Formation of via holes by UV-YAG laser

Hole with a small diameter was formed in the insulating layer of the evaluation substrate (a) using a UV-YAG laser processing machine ("LU-2L212 / M50L" manufactured by VIA MECHANICS CO., LTD.). The following conditions I-1, I-2, I-3, I-3 and I- -4 to form a via-hole. The resulting substrate is referred to as &quot; evaluation substrate (b) &quot;.

Condition I-1: power 0.08 W, number of shots 15, target column diameter 10 탆

Condition I-2: power 0.08 W, number of shots 25, target top diameter 10 탆

Condition I-3: power 0.17 W, number of shots 25, target top diameter 15 탆

Condition I-4: Power 0.17 W, Shot Number 60, Target Top Diameter 15 m

&Lt; Measurement of arithmetic mean roughness (Ra) >

The evaluation substrate (a) was evaluated by a numerical value obtained by setting the measurement range to 121 占 퐉 92 占 퐉 using a non-contact surface roughness meter ("WYKO NT3300" manufactured by Vico Instruments Inc.) Ra value was obtained. An average value of 10 randomly selected samples was obtained for each sample.

&Lt; Evaluation of particle diameter of inorganic filler in insulating layer >

The cross-section of the insulating layer was observed with respect to the evaluation board (b) using an FIB-SEM composite device ("SMI3050SE" manufactured by SII Nanotechnology Co., Ltd.). Specifically, a cross section in the direction perpendicular to the surface of the evaluation substrate was scraped off by a FIB (focused ion beam) to obtain a SEM image of a cross section (observation width 30 占 퐉, observation magnification x9000). For each sample, 10 cross-sectional SEM images were selected randomly.

For each of the obtained 10 sections of SEM images, a rectangular area having a total width of 15 mu m (total thickness (length) x 15 mu m (width)) of 15 mu m in width, ), And the average value (n ¹ ) of the inorganic filler was obtained. And a value (n ² ) (average particle diameter) obtained by multiplying the average value (n ¹ ) by 1.27 was calculated. Further, when the amount of the inorganic filler exceeding half of the maximum diameter of the inorganic filler is in the region of 15 占 퐉 in width, the inorganic filler is determined to be included in the region of 15 占 퐉 width.

&Lt; Measurement of Resin Area and Insulating Filler Area in Insulating Layer Section >

The cross-section of the insulating layer was observed with respect to the evaluation board (b) using an FIB-SEM composite device ("SMI3050SE" manufactured by SII Nanotechnology Co., Ltd.). Specifically, a cross section in the direction perpendicular to the surface of the evaluation substrate was scraped off by a FIB (focused ion beam) to obtain a SEM image of a cross section (observation width 30 占 퐉, observation magnification x9000). For each sample, 10 cross-sectional SEM images were selected randomly. For each of the obtained 10 sections of SEM images, a rectangular area having a total width of 15 mu m (total thickness (length) x 15 mu m (width)) of 15 mu m in width, (A ₁ ) and the inorganic filler area (A ₂ ) were measured, and the value of A ₂ / (A ₁ + A ₂ ) was calculated from the obtained A ₁ value and A ₂ value.

Specifically, the resin area (A ₁ ) and the inorganic filler area (A ₂ ) were saved as an image by SEM observation, and the resin part was black and the inorganic filler part other than resin was white, And the number of bits of the black portion was taken as the resin area (A ₁ ), and the number of bits of the white portion was taken as the inorganic filler area (A ₂ ).

&Lt; Evaluation of via shape >

The surface of the evaluation board (b) was observed with a scanning electron microscope (&quot; S-4800 &quot; manufactured by Hitachi High-Technologies Corporation). Opening diameter of the via-hole from the obtained image (D) and was measured via a minimum diameter (D _min) of the hole. D and D _min were measured for 10 via holes and the average value of D _min / D ratio was determined. The shape of the via was evaluated by the following evaluation criteria based on the average value of the obtained _Dmin / D ratio.

Evaluation standard:

?: D _min / D ratio of 0.65 or more

×: D _min / D ratio less than 0.65

Preparation Example 1 Preparation of resin varnish (1)

, 10 parts of a bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent weight: about 238), 15 parts of a biphenyl type epoxy resin (NC3000L manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: 269) 10 parts of a biscylenol type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 185), 10 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Kagaku K.K., a cyclohexanone: (1: 1 solution of methyl ethyl ketone (MEK)) were dissolved by heating in 5 parts of solvent naphtha and 2 parts of MEK with stirring. After cooling to room temperature, 4 parts of a phenazine novolak type curing agent containing a triazine skeleton (hydroxyl equivalent of 125, "LA-7054" manufactured by DIC Corporation, MEK solution having a solid content of 60%) and an active ester type curing agent (DIC 18 parts of an amine-based curing accelerator (4-dimethylaminopyridine (DMAP), 5 parts by mass of a solid content of a MEK solution (trade name: HPC-8000-65T, active group equivalent: about 223 and a nonvolatile component of 65% ), 2 parts of spherical silica ("UFP-30" manufactured by Denki Kagaku Kogyo Co., Ltd.) surface-treated with N-phenyl-3-aminopropyltrimethoxysilane (KBM573 manufactured by Shin- 0.1㎛ average particle diameter, a specific surface area of 30m ² / g, carbon amount per surface area unit of 0.36mg / m ²⁾ 40 parts after the mixture and uniformly dispersed in a high-speed rotary mixer, a filter cartridge (Co., Rocky techno manufacture "SCP -010 &quot;, filtration efficiency (maker nominal value): 99.9% or more of particles having a size of 1 mu m or more cut out) to prepare a resin varnish 1.

Preparation Example 2 Preparation of resin varnish (2)

, 12 parts of bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 238), 12 parts of biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: 269) (YX4000HK manufactured by Mitsubishi Kagaku Co., Ltd., epoxy equivalent: about 185), and phenoxy resin (YX7553BH30 manufactured by Mitsubishi Kagaku Co., Ltd., cyclohexanone having a solid content of 30 mass% (1: 1 solution of methyl ethyl ketone (MEK)) was dissolved by heating in 25 parts of solvent naphtha and 6 parts of MEK while stirring. After cooling to room temperature, 6 parts of a triazine skeleton-containing cresol novolac curing agent (hydroxyl equivalent 151, "LA-3018-50P" manufactured by DIC Corporation, 50% solids in 2-methoxypropanol solution) , 16 parts of an active ester type curing agent ("HPC-8000-65T" manufactured by DIC Corporation, active group equivalent of about 223, and a toluene solution of a nonvolatile component of 65 mass%), 16 parts of an amine curing accelerator (4-dimethylaminopyridine (MEK solution having a solid content of 5% by mass), 2 parts of spherical silica surface treated with N-phenyl-3-aminopropyltrimethoxysilane (KBM573 manufactured by Shin-Etsu Chemical Co., (UFP-30, average particle diameter 0.1 μm, specific surface area 30 m ² / g, and carbon content 0.36 mg / m ² per unit surface area) were mixed and uniformly dispersed in a high-speed rotary mixer. SCP-010 manufactured by Rocky Techno Co., Ltd .; filtration efficiency (maker nominal value): 99.9% or more of particles having a particle size of 1 μm or more cut) (2) it was prepared.

&Lt; Preparation Example 3 > (Preparation of resin varnish (3)) [

, 5 parts of a bisphenol-type epoxy resin ("ZX1059" manufactured by Shinnitetsu Sumikin Kagaku Co., Ltd., a 1: 1 mixture of bisphenol A type and bisphenol F type, an epoxy equivalent of about 169), 5 parts of a naphthalene type epoxy resin , 20 parts of a dicyclopentadiene type epoxy resin ("HP-7200HH" manufactured by DIC Corporation, epoxy equivalent weight 280), 5 parts of a phenoxy resin (Mitsubishi Kagaku Co., 20 parts of cyclohexanone: 1: 1 solution of &quot; YX7553BH30 &quot;, solid component 30% by mass of cyclohexanone: MEK) were dissolved by heating in 6 parts of MEK with stirring. After cooling to room temperature, 10 parts of a triazine skeleton-containing phenol novolac curing agent (hydroxyl equivalent weight 125, "LA-7054" manufactured by DIC Corporation, MEK solution having a solid content of 60%) 10 parts of a naphthol curing agent , 10 parts of a polyvinyl butyral resin (glass transition temperature: 105 占 폚, KS (trade name, manufactured by Sekisui Chemical Co., Ltd.) 15 parts of a mixed solution of ethanol and toluene in a solid content of 15% of a solid content of 1% by weight of an amine-based curing accelerator (4-dimethylaminopyridine (DMAP), 5 parts by mass of a solid content MEK solution) (Average particle diameter 2 mu m) &quot; HCA-HQ &quot;, 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphenanthrene- ("UFP-60S" manufactured by Denki Kagaku Kogyo Co., Ltd.) surface-treated with N-phenyl-3-aminopropyltrimethoxysilane (KBM573 manufactured by Shin-Etsu Chemical Co., 0.08 And a specific surface area of 60m ² / g, a carbon amount per unit surface suitable mixing 0.34mg / m ²⁾ 25 parts, and then uniformly dispersed in a high-speed rotary mixer, a filter cartridge (Co., Rocky Techno manufacture "SCP-010", filtered Efficiency (maker nominal value): 99.9% or more of particles having a particle size of 1 탆 or more were cut out) to prepare resin varnish 3.

&Lt; Preparation Example 4 > (Preparation of resin varnish (4)) [

, 12 parts of bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 238), 12 parts of biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: 269) (YX4000HK manufactured by Mitsubishi Kagaku Co., Ltd., epoxy equivalent: about 185), and phenoxy resin (YX7553BH30 manufactured by Mitsubishi Kagaku Co., Ltd., cyclohexanone having a solid content of 30 mass% (1: 1 solution of methyl ethyl ketone (MEK)) were dissolved by heating in 20 parts of solvent naphtha and 4 parts of MEK with stirring. After cooling to room temperature, 6 parts of a triazine skeleton-containing cresol novolac curing agent (hydroxyl equivalent 151, "LA-3018-50P" manufactured by DIC Corporation, 50% solids in 2-methoxypropanol solution) , 16 parts of an active ester type curing agent ("HPC-8000-65T" manufactured by DIC Corporation, active group equivalent of about 223, and a toluene solution of a nonvolatile component of 65 mass%), 16 parts of an amine curing accelerator (4-dimethylaminopyridine (Manufactured by Adomatech Co., Ltd.), which had been surface-treated with 2 parts of N-phenyl-3-aminopropyltrimethoxysilane (KBM573 manufactured by Shin-Etsu Chemical Co., "SO-C1", average particle diameter 0.30㎛, a specific surface area of 10m ² / g, carbon amount per surface area unit of 0.36mg / m ²⁾ 80 parts after the mixture and uniformly dispersed in a high-speed rotary mixer, a filter cartridge ((Note ) Filtering with resin varnish 4 ("SHP-030" manufactured by Rocky Techno Co., Ltd .; filtration efficiency (maker nominal value) It was prepared.

&Lt; Preparation Example 5 > (Preparation of resin varnish (5)) [

, 12 parts of bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 238), 12 parts of biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent weight: 269) (YX4000HK manufactured by Mitsubishi Kagaku Co., Ltd., epoxy equivalent: about 185), and phenoxy resin (YX7553BH30 manufactured by Mitsubishi Kagaku Co., Ltd., cyclohexanone having a solid content of 30 mass% (1: 1 solution of methyl ethyl ketone (MEK)) were dissolved by heating in 15 parts of solvent naphtha and 2 parts of MEK with stirring. After cooling to room temperature, 6 parts of a triazine skeleton-containing cresol novolac curing agent (hydroxyl equivalent 151, "LA-3018-50P" manufactured by DIC Corporation, 50% solids in 2-methoxypropanol solution) , 16 parts of an active ester type curing agent ("HPC-8000-65T" manufactured by DIC Corporation, active group equivalent of about 223, and a toluene solution of a nonvolatile component of 65 mass%), 16 parts of an amine curing accelerator (4-dimethylaminopyridine (Manufactured by Adomatech Co., Ltd.), which had been surface-treated with 2 parts of N-phenyl-3-aminopropyltrimethoxysilane (KBM573 manufactured by Shin-Etsu Chemical Co., , 80 parts of a carbon black ("SO-C2", average particle diameter of 0.50 μm, specific surface area of 6 m ² / g, and carbon content of 0.39 mg / m ² per unit surface area) were mixed and uniformly dispersed by a high- ) Filtered with a resin varnish 5 ("SHP-050" manufactured by Rocky Techno Co., Ltd .; filtration efficiency (manufacturer nominal value): 99.9% It was prepared.

&Lt; Production Example 1 > Production of adhesive film (1)

("Lumirror T6AM" manufactured by Toray Co., Ltd., thickness 38 탆, softening point 130 캜) which had been subjected to release treatment with an alkyd resin-based release agent ("AL-5" manufactured by Lintec Corporation) was prepared as a support. The releasable surface of the support was coated with a resin varnish (1) with a die coater and dried at 80 캜 to 110 캜 (average 100 캜) for 1.5 minutes to form a resin composition layer. The thickness of the resin composition layer was 10 mu m. Subsequently, a polypropylene film ("ALPAN MA-411", manufactured by Oji Torque Co., Ltd., thickness: 15 μm) as a protective film was laminated on the surface of the resin composition layer not bonded to the support, Layer to form an adhesive film (1).

&Lt; Production Example 2 > Production of adhesive film (2)

("Lumirror T6AM" manufactured by Toray Co., Ltd., thickness 38 탆, softening point 130 캜) which had been subjected to release treatment with an alkyd resin-based release agent ("AL-5" manufactured by Lintec Corporation) was prepared as a support. The releasable surface of the support was coated with a resin varnish (2) with a die coater and dried at 80 캜 to 110 캜 (average 100 캜) for 2 minutes to form a resin composition layer. The thickness of the resin composition layer was 15 占 퐉. Subsequently, a polypropylene film ("ALPAN MA-411", manufactured by Oji Torque Co., Ltd., thickness: 15 μm) as a protective film was laminated on the surface of the resin composition layer not bonded to the support, Layer to form an adhesive film (2).

&Lt; Production Example 3 > Production of adhesive film (3)

An adhesive film (3) was produced in the same manner as in Production Example 2 except that the resin varnish (3) was used in place of the resin varnish (2).

&Lt; Production Example 4 > Production of adhesive film (4)

An adhesive film (4) was produced in the same manner as in Production Example 2 except that the resin varnish (4) was used in place of the resin varnish (2).

&Lt; Production Example 5 > Production of adhesive film (5)

An adhesive film (5) was produced in the same manner as in Production Example 2 except that the resin varnish (5) was used in place of the resin varnish (2).

&Lt; Example 1 >

An evaluation substrate was prepared in accordance with the above-mentioned [preparation of a substrate for measurement and evaluation] using the adhesive film 1, and each evaluation was carried out.

&Lt; Example 2 >

An evaluation substrate was prepared according to the above-mentioned [preparation of a substrate for measurement and evaluation] using the adhesive film 2, and each evaluation was carried out.

&Lt; Example 3 >

An evaluation substrate was prepared in accordance with the above-mentioned [preparation of a substrate for measurement and evaluation] using the adhesive film 3, and each evaluation was carried out.

&Lt; Comparative Example 1 &

An evaluation substrate was prepared in accordance with the above-described [preparation of a substrate for measurement and evaluation] using the adhesive film 4, and each evaluation was carried out.

&Lt; Comparative Example 2 &

An evaluation substrate was prepared in accordance with the above-described [preparation of a substrate for measurement and evaluation] using the adhesive film 4, and each evaluation was carried out.

&Lt; Comparative Example 3 &

An evaluation substrate was prepared according to the above-mentioned [preparation of a substrate for measurement and evaluation] using the adhesive film 5, and each evaluation was carried out.

The evaluation results are shown in Table 2.

1: Inner layer substrate
10: Insulation layer
11: Resin component
12: inorganic filler

Claims (19)

A circuit board comprising an insulating layer having a via-hole having an opening diameter of 15 mu m or less,
The arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less,
Wherein the insulating layer comprises an inorganic filler,
When the average value of the maximum diameter of the inorganic filler contained in the region of the predetermined width is n ¹ (탆) in the cross section of the insulating layer in the direction perpendicular to the surface of the insulating layer, a value n ¹ × 1.27 (n ² ) is 0.2 탆 or less. The circuit board according to claim 1, wherein the surface of the insulating layer has an Ra of 100 nm or less. The circuit board according to claim 1, wherein the opening diameter of the via-hole is 12 占 퐉 or less. The method of claim 1, wherein the surface of the insulating layer to the cross-section of such insulating layers in the vertical direction, the resin area (A ₁₎ and an inorganic filler surface area (A ₂₎ of a predetermined width zone of 0.1≤A ₂ / (A ₁ + A &_lt; ₂ &gt;). The method of claim 1, wherein the via-hole opening diameter (D) and the via-hole in the minimum diameter (D _min), the circuit board to satisfy the 0.65≤Dmin / D. The circuit board of claim 1, wherein the insulating layer comprises an inorganic filler surface-treated with a silane compound comprising an organic group having an aromatic ring. The circuit board of claim 1, wherein the inorganic filler is silica. A semiconductor device comprising the circuit board according to any one of claims 1 to 7. (A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;
(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And
(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,
Wherein the insulating layer formed in the step (B) includes an inorganic filler and an average value of a maximum diameter of the inorganic filler contained in the region of the predetermined width in the cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer is n ¹ (N ² ) of n ¹ × 1.27 is not more than 0.2 μm when the thickness (m ² ) is defined as (μm). (A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;
(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And
(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,
Wherein the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having a BET specific surface area of 20 m ² / g or more. (A) a step of laminating an adhesive film comprising a support and a resin composition layer provided on the support onto an inner layer substrate so as to bond the resin composition layer to the inner layer substrate;
(B) a step of thermally curing the resin composition layer in a state where a support is attached to form an insulating layer; And
(C) forming a via hole having an opening diameter of 15 mu m or less in an insulating layer by a UV solid laser,
Wherein the resin composition layer of the adhesive film used in the step (A) contains 30 mass% or more of an inorganic filler having an average particle diameter of 0.2 占 퐉 or less. The method according to claim 10, wherein the inorganic filler has a BET specific surface area of 20 m ² / g or more and 500 m ² / g or less. 12. The method according to claim 11, wherein the inorganic filler has an average particle diameter of not less than 0.01 mu m and not more than 0.2 mu m. 12. The method according to any one of claims 9 to 11, wherein the support is removed prior to step (C). The method according to any one of claims 9 to 11, wherein an arithmetic average roughness (Ra) of the surface of the insulating layer is 150 nm or less. The method of manufacturing a semiconductor device according to any one of claims 9 to 11, wherein a resin area (A ₁ ) and an inorganic filler area (A ₂ ) in a predetermined width region are formed in a cross section of the insulating layer in a direction perpendicular to the surface of the insulating layer, the 0.1≤A ₂ /, how to satisfy (a ₁ + a _2). 12. The method according to any one of claims 9 to 11, wherein the opening diameter D of the via-hole and the minimum diameter Dmin of the via-hole satisfy 0.65? Dmin / D. 12. The method according to any one of claims 9 to 11, wherein the insulating layer comprises an inorganic filler surface-treated with a silane compound comprising an organic group having an aromatic ring. 12. The method according to any one of claims 9 to 11, wherein the inorganic filler is silica.

Images