JP2008103640A - Multilayer wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer wiring board having high degree of freedom in designing, excellent bondability, and satisfactory production efficiency. <P>SOLUTION: The board 100a includes multilayer resin layers 110a each having a first layer 111 which includes thermoplastic resin, a second layer 112 which includes thermosetting resin, and piercing conductors 113, and wiring boards 120 each having conductors 123, wherein the board includes laminating structure sections, in each of which the multilayer resin layer 110a and the wiring board 120 are laminated at the second layer 112 side and the conductor 123 side, while the piercing conductors 113 and the conductors 123 are electrically connected. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multilayer wiring board. More specifically, the present invention relates to a multilayer wiring board having a high degree of design freedom, excellent bonding properties, and high manufacturing efficiency.

  Conventional multilayer wiring boards include: (1) glass epoxy boards (substrates made by impregnating and curing epoxy resin on glass cloth) and bismaleimide / triazine boards, etc. that have high heat resistance and high strength and excellent core retention There is known a multilayer wiring board in which prepregs and wiring patterns are alternately laminated on the surface of the substrate. In addition, (2) a multilayer wiring board is known in which single-layer resin flexible boards having wiring patterns formed on one or both sides of a high heat-resistant resin layer such as polyimide resin are laminated together via an adhesive layer such as an epoxy resin. It has been. Further, (3) as shown in the following Patent Document 1, a special thermoplastic resin layer excellent in heat-fusibility is used, and each layer in which a through conductor and a wiring pattern are formed is laminated on this thermoplastic resin layer. A multilayer wiring board is known.

JP 2000-38464 A

  In the multilayer wiring board of the above (1), since the prepreg does not have sufficient shape retention by itself, there is a problem that it is inferior in handling property during production. Moreover, since it does not have sufficient shape retainability, a core substrate is required, and there is a problem that design flexibility is limited. Furthermore, there is a problem that a multilayer wiring board laminated using prepreg cannot be made flexible. In addition, it is necessary to cure each time the layers are stacked. For this reason, the workability is not always good. If the number of layers is increased, the number of times of curing increases, so that there is a problem that a heat history is easily accumulated in the inner layer. Furthermore, in recent years, there has also been a problem that it is difficult to impart higher heat resistance than required by the use of lead-free solder.

  In recent years, a core substrate is not used due to the limitation of high density in a wiring board, and instead of a conventional through hole, a stacked via structure {particularly, a via formed by stacking over all layers (hereinafter simply referred to as an “all layer IVH structure”). However, in the multilayer wiring board of the above (2), it is not possible to obtain an all-layer IVH structure in the case of manufacturing by a batch lamination method, and all layers by a build-up method. The formation of the IVH structure is expensive, and it is difficult to obtain a sufficient degree of design freedom and manufacturing efficiency, and further, it is difficult to sufficiently obtain heat resistance by the adhesive layer between the layers.

  In the multilayer wiring board of (3), there is a problem that it is difficult to obtain strong bondability as in the case where a prepreg is used to obtain interlayer bonding from a thermoplastic resin. Further, even if the thermoplastic resin has a low viscosity when heated to such an extent that it can be heat-sealed and has a low coefficient of thermal expansion, it is difficult to exceed the excellent conformability of the thermosetting resin to the uneven shape. That is, since it does not have excellent plastic deformability like a prepreg, there is a problem that it is difficult to obtain sufficient followability with respect to fine uneven surfaces when it is made multilayer.

  The present invention has been made in view of the above, and relates to a multilayer wiring board having a high degree of design freedom and high manufacturing efficiency.

The present invention is as follows.
(1) A first resin layer containing a thermoplastic resin, a second resin layer containing a thermosetting resin provided on at least one surface of the first resin layer, and the first resin layer and the second resin layer A multilayer resin layer having a through conductor penetrating through the resin layer;
A wiring board having a conductor pattern on at least one side,
The multilayer resin layer and the wiring board are laminated on the second resin layer side and the conductor pattern side, and have a laminated structure portion in which the through conductor and the conductor pattern are electrically connected. A multilayer wiring board characterized by that.
(2) The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The laminated structure section includes two wiring boards, and the first wiring board of the wiring boards, the multilayer resin layer, and the second wiring board of the wiring boards are in this order. Laminated,
The multilayer resin layer and the first wiring board are laminated on the second resin layer side of one surface and the conductor pattern side included in the first wiring board,
The multilayer resin layer and the second wiring board are laminated on the second resin layer side of the other surface and the conductor pattern side included in the second wiring board,
The multilayer wiring board according to (1), wherein the conductor pattern provided in the first wiring board and the conductor pattern provided in the second wiring board are electrically connected via the through conductor.
(3) The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The multilayer wiring board according to (1), wherein the multilayer structure includes a heat sink made of metal, and the wiring board, the multilayer resin layer, and the heat sink are stacked in this order.
(4) The multilayer wiring board according to any one of (1) to (3), wherein the wiring board is a flexible substrate.
(5) The multilayer wiring board according to any one of (1) to (4), wherein the resin portion constituting the wiring board has a 1% weight loss temperature of 300 ° C. or higher.
(6) The multilayer wiring board according to (5), wherein the resin portion constituting the wiring board has a glass transition point of 180 ° C. or higher.
(7) The multilayer according to any one of (1) to (6), wherein the thickness of the second resin layer is 1/40 to 1/2 of the thickness of the first resin layer. Wiring board.
(8) The thermal expansion coefficient in the planar direction of the first resin layer is α ¹ _xy , the thermal expansion coefficient in the thickness direction of the first resin layer is α ¹ _z, and the thermal expansion of the through conductors in the case where the coefficient was α ^3,
−10 × 10 ⁻⁶ ≦ α ¹ _xy (/ ° C.) ≦ 30 × 10 ⁻⁶ ,
The multilayer wiring board according to any one of (1) to (7), wherein α ¹ _z ≧ α ³ .
(9) When the thermal expansion coefficient in the planar direction of the second resin layer is α ² _xy, and the thermal expansion coefficient in the thickness direction of the second resin layer is α ² _z ,
10 × 10 ⁻⁶ ≦ α ² _xy (/ ° C.) ≦ 60 × 10 ⁻⁶ ,
The multilayer wiring board according to any one of (1) to (8), wherein 10 × 10 ⁻⁶ ≦ α ² _z (/ ° C.) ≦ 60 × 10 ⁻⁶ .

  According to the multilayer wiring board of the present invention, it is possible to provide a multilayer wiring board having a high degree of design freedom, excellent bonding properties with other layers, and high manufacturing efficiency. That is, for example, in order to obtain interlayer conduction as in the prior art, there is no problem of forming a through hole that penetrates all the layers after multilayering and forming a through hole in an originally unnecessary layer. In addition, since the second resin layer containing the thermosetting resin excellent in bondability is provided on the outer surface side, the excellent bondability can be exerted on a wide range of materials to be bonded. Wide selection range and high design freedom. Further, the thermosetting resin constituting the coat layer exhibits a shrinkage behavior upon curing, and the shrinkage behavior can be obtained in the entire multilayer resin layer. For this reason, compressive stress is applied to the through conductor, and each of the adhesion reliability between the through conductor and the multilayer resin layer and the electrical conductivity of the through conductor are improved. Furthermore, since the multilayer wiring board of the present invention can be laminated together, it is excellent in manufacturing efficiency. Further, it is not necessary to use a core substrate as in the case of using only a prepreg, and a coreless multilayer wiring substrate can be obtained, and a stacked via structure (particularly, an all-layer IVH structure) can be obtained.

  Although flexibility is obtained even in the multilayered portion of the multilayer wiring board of the present invention, in particular, when each wiring board constituting the multilayer wiring board of the present invention is a flexible substrate, it is partially flexible. A multilayer wiring board can be obtained. And the structure where the two board | substrate parts of a rigid part and a flexible part were connected without using a connector can be obtained. For this reason, it is possible to obtain a multilayer wiring board particularly excellent in space saving.

When the 1% weight loss temperature of the resin part constituting the wiring board is 300 ° C. or higher, a multilayer board having excellent heat resistance can be obtained.
When the glass transition point of the resin part constituting the wiring board is 180 ° C. or higher, the curing temperature of the thermosetting resin used for the second resin layer and the appropriate temperature of the thermoplastic resin constituting the first resin layer The temperature range in which fluidity can be obtained can be controlled in an overlapping temperature range.

  When the thickness of the second resin layer is 1/40 to 1/2 of the thickness of the first resin layer, the characteristics of the first resin layer and the characteristics of the second resin layer are within this range. In particular, it can be obtained synergistically. That is, the shape retention property as the whole multilayer resin layer can be sufficiently secured. In addition, the through conductor can be reliably formed. Furthermore, excellent bondability and excellent followability are sufficiently exhibited. Moreover, the fluidity | liquidity of the thermoplastic resin at the time of a heating can fully be suppressed.

The thermal expansion coefficient α ¹ _{xy of} the first resin layer, the thermal expansion coefficient α ¹ _z, and the thermal expansion coefficient α ³ of the through conductor are −10 × 10 ⁻⁶ ≦ α ¹ _xy (/ ° C. ) ≦ 30 × 10 ⁻⁶ and α ¹ _z ≧ α ³ , peeling or delamination between the first resin layer and the second resin layer and between the multilayer resin layer and the wiring board It can be prevented more effectively.
The thermal expansion coefficient α ² _xy of the second resin layer and the thermal expansion coefficient α ² _z of the second resin layer are 10 × 10 ⁻⁶ ≦ α ² _xy (/ ° C.) ≦ 60 × 10. ⁻⁶ and 10 × 10 ⁻⁶ ≦ α ² _z (/ ° C.) ≦ 60 × 10 ⁻⁶ , between the first resin layer and the second resin layer, and between the multilayer resin layer and the wiring board Peeling and delamination can be prevented more effectively. In particular, even when the second resin layer contains a filler (for the purpose of reducing the difference in thermal expansion from other layers, etc.), the thermosetting resin (state prior to complete curing) can be maintained within the range of the above relational expression. ) Can be sufficiently ensured in fluidity (followability to other layers).

The present invention will be described in detail below.
[1] Multilayer wiring board The multilayer wiring board of the present invention includes a first resin layer containing a thermoplastic resin, a second resin layer containing a thermosetting resin provided on at least one surface of the first resin layer, and A multilayer resin layer having a through conductor penetrating the first resin layer and the second resin layer, and a wiring board having a conductor pattern on at least one surface, the multilayer resin layer and the wiring board Are laminated on the second resin layer side and the conductor pattern side, and have a laminated structure portion in which the through conductor and the conductor pattern are electrically connected.

The multilayer wiring board of the present invention includes the multilayer structure.
The “laminated structure part” includes the multilayer resin layer and the wiring board.
The “multilayer resin layer” includes at least a first resin layer, a second resin layer, and a through conductor.
The “first resin layer” is a layer containing a thermoplastic resin. The 1st resin layer may consist only of a thermoplastic resin, and may contain a thermoplastic resin and another component other than that. This first resin layer usually functions as a support layer in the multilayer resin layer.

  Examples of the “thermoplastic resin” include polyaryl ketone resins, polyimide resins, liquid crystal polymers, and polyolefin resins. These thermoplastic resins may use only 1 type and may use 2 or more types together. Among the above, as the polyaryl ketone resin, polyether ether ketone resin (hereinafter also simply referred to as “PEEK”), polyether ketone resin (hereinafter also simply referred to as “PEK”), polyether ketone ketone resin (hereinafter referred to as “PEEK”). Simply referred to as “PEKK”). Among these, PEEK is preferable, and PEEK having a melting point of 260 ° C. or higher is more preferable. Among the above, examples of the polyimide resin include polyetherimide resin (hereinafter also simply referred to as “PEI”), thermoplastic polyimide resin, polyamideimide resin, and the like. Of these, PEI is preferred.

Among these, a composite resin or a liquid crystal polymer of a polyaryl ketone resin and a polyimide resin is preferable, a composite resin of PEEK and PEI or a liquid crystal polymer is more preferable, and a composite resin of PEEK and PEI is particularly preferable. .
In the composite resin of PEEK and PEI, the blending ratio of each resin is not particularly limited. However, when the total of PEEK and PEI is 100% by mass, PEEK is preferably 35 to 65% by mass ( That is, PEI is 65 to 35% by weight). Furthermore, it is preferable that the glass transition point of this composite resin is 150-230 degreeC. Within the above blending range, and further within the above glass transition point range, a balance among heat resistance, bonding strength and thermal expansion coefficient can be maintained.

The first resin layer may contain other components in addition to the thermoplastic resin. However, other components may be contained within a range that satisfies the object of the present invention. Usually, when the entire first resin layer is 100% by volume, the other components other than the thermoplastic resin are 70% by volume or less (preferably 60% by volume or less, more preferably 50% by volume or less, 0% by volume). May be).
Examples of other components include a filler and a core material. When these fillers and / or core materials are contained, the thermoplastic resin serves as a matrix for these components. This filler may be an inorganic filler or an organic filler, but is preferably an inorganic filler in order to have a good balance of thermal expansion coefficient, heat resistance and electrical characteristics.

The inorganic filler is a filler made of an inorganic material. Examples of the inorganic filler include ceramic fillers made of calcium carbonate, silicon oxide, aluminum oxide, talc, aluminum nitride, barium sulfate, and the like. Moreover, the dielectric filler which consists of barium titanate, strontium titanate, lead titanate, lead zirconate titanate, etc. is mentioned. These inorganic fillers may use only 1 type and may use 2 or more types together. Moreover, the shape of a filler is not specifically limited, An indefinite shape, a spherical shape, a fiber shape, and a plate shape are mentioned. These fillers may be used alone or in combination of two or more.
On the other hand, examples of the core material include glass fiber, carbon fiber, glass cloth, carbon cloth, and nonwoven fabric (nonwoven fabric using at least one of glass fiber, carbon fiber, and organic fiber). These may use only 1 type and may use 2 or more types together.

The “second resin layer” is a layer containing a thermosetting resin. The second resin layer may be composed of only a thermosetting resin, and may contain a thermoplastic resin and other components. The thermosetting resin contained in the second resin layer is a resin that is in an uncured state before being laminated with the wiring substrate and is cured at the time of bonding. However, the uncured state is a state before the thermosetting resin is completely cured, and includes a semi-cured state and a completely uncured state.
The second resin layer is a layer provided on at least one side of the first resin layer. That is, the second resin layer may be provided only on one side of the first resin layer, or may be provided on both sides of the first resin layer.

  As the thermosetting resin constituting the “thermosetting resin” (the thermosetting resin is formed by curing the thermosetting resin), a thermosetting polyimide resin, a thermosetting bismaleimide resin, an epoxy resin, a silicon resin, Examples include polyphenylene ether resin. Among these, thermosetting polyimide resins and thermosetting bismaleimide resins are preferable, and thermosetting polyimide resins are particularly preferable. This is because thermosetting polyimide is excellent in bondability and heat resistance. These thermosetting resins may use only 1 type and may use 2 or more types together.

  The second resin layer may contain other components in addition to the thermosetting resin. Examples of other components include a curing agent (which may be a curing agent residue that has achieved its function after curing), a curing accelerator, and a filler (the filler in the first resin layer can be applied as it is). . Furthermore, other components in the first resin layer are added. These may use only 1 type and may use 2 or more types together. Usually, when the second resin layer is 100% by volume, the other components are 70% by volume or less (preferably 60% by volume or less, more preferably 50% by volume or less, or 0% by volume). It is.

It is preferable that the second resin layer has a specific correlation between the thermal expansion coefficient in the plane direction and the thermal expansion coefficient in the thickness direction by itself. That is, when the thermal expansion coefficient in the planar direction of the second resin layer is α ² _xy and the thermal expansion coefficient in the thickness direction of the second resin layer is α ² _z , 10 × 10 ⁻⁶ It is preferable that ≦ α ² _xy (/ ° C.) ≦ 60 × 10 ⁻⁶ and 10 × 10 ⁻⁶ ≦ α ² _z (/ ° C.) ≦ 60 × 10 ⁻⁶ . Within this range, peeling and delamination between the first resin layer and the second resin layer and between the multilayer resin layer and the wiring board can be more effectively prevented. In particular, even when the second resin layer contains the filler (for the purpose of reducing the difference in thermal expansion from other layers, etc.), if α ² _xy and α ² _z are within the above ranges, thermosetting Fluidity (followability to other layers, other parts, their surfaces, patterns of other layers, etc.) at the time of lamination of the resin (state before complete curing) can be sufficiently secured. Therefore, the balance of fluidity (followability to other layers) at the time of lamination of the second resin layer and suppression of the difference in thermal expansion between the second resin layer after curing and the other layers is maintained within a preferable range. be able to.
In addition, the measuring method of each said thermal expansion coefficient is mentioned later.

The “penetrating conductor” is a conductor penetrating the first resin layer and the second resin layer. (1) When the second resin layer is provided only on one surface of the first resin layer, the through conductor includes the first resin layer and the second resin layer on one surface thereof. Further, (2) when the second resin layer is provided on both sides of the first resin layer, the through conductor may be provided through the first resin layer and the second resin layer on both sides thereof. It may be provided through only one of the first resin layer and the second resin layer.
The shape of the through conductor is not particularly limited, but is usually a substantially cylindrical shape. The size of the through conductor is not particularly limited, but usually the diameter (maximum length in the case of a non-cylindrical shape) is 300 μm or less.

  Examples of the through conductor include a conductor (hereinafter simply referred to as “pressure contact type through conductor”) made of a conductor paste (hereinafter simply referred to as “pressure contact type paste”) containing a resin and a conductive filler. Furthermore, a conductor paste (hereinafter simply referred to as “metal-bonded paste”) containing at least one of silver oxide particles, organometallic compounds, ultrafine metal particles, and low melting point metal particles as a main component was sintered at low temperature. Examples thereof include conductors (hereinafter simply referred to as “metal-bonded through conductors”) that are substantially made of only a conductive material (for example, a metal material). These conductors may use only 1 type and may use 2 or more types together.

  Among the above, the kind of resin constituting the press-contact type through conductor is not particularly limited, and may be a thermoplastic resin or a thermosetting resin. Among these, as a thermoplastic resin, the thermoplastic resin contained in the said 1st resin layer can be applied as it is. However, the resin of the first resin layer and the resin of the through conductor may be the same or different.

  Moreover, as a conductive filler which comprises a press-contact type penetration conductor, a metal filler, a carbon filler, etc. are mentioned. Examples of the metal filler include fillers made of metals such as copper, silver, gold, platinum, aluminum, and nickel. Only 1 type may contain these metals and 2 or more types may contain them. Examples of the carbon filler include fillers made of carbon such as carbon black and carbon nanotubes. Only one kind of these carbons may be contained, or two or more kinds thereof may be contained. Moreover, these metal fillers, carbon fillers, etc. may use only 1 type and may use 2 or more types together. Furthermore, the shape of the conductive filler is not particularly limited, and examples thereof include a spherical shape, a column shape, a needle shape, a flat plate shape, and a fiber shape. These shapes may use only 1 type and may use 2 or more types together. Among these shapes, a spherical shape is preferable.

The size of the conductive filler in the press-contact type through conductor is not particularly limited, but the average particle diameter (maximum length in a shape other than a spherical shape) is 10 μm or less (more preferably 8 μm or less, and further preferably 1 to 7 μm). It is preferable. Within this range, the conductive paste can be filled particularly smoothly during the production of the multilayer resin layer.
Furthermore, the ratio of the resin and the conductive filler contained in the press-contact through conductor is not particularly limited, but when the total of the resin and the conductive filler is 100% by volume, the conductive filler is 40% by volume. It is preferable that it is above (more preferably 45% by volume or more, further preferably 50% by volume or more). Within this range, excellent conductivity can be obtained.

  On the other hand, the metal species constituting the metal bonded through conductor is not particularly limited. For example, silver, copper, tin, lead, gold, aluminum and the like can be mentioned. The paste for obtaining this through conductor usually contains at least one of silver oxide particles, organometallic compounds, ultrafine metal particles and low melting point metal particles as a main component. The silver oxide-containing paste is a paste from which a silver conductor can be obtained by heat-sealing characteristics during heat reduction of silver oxide. The paste containing the organometallic compound is a paste in which the organic portion of the organometallic compound is burned off by thermal decomposition to obtain a metal conductor. The paste containing ultrafine metal particles is a paste in which a metal conductor is obtained by heat fusion with each other due to the high surface activity of the ultrafine metal particles. The paste containing the low melting point metal particles is a paste in which the low melting point metal particles are heat-fused to obtain a metal conductor. These metal bond type pastes may use only 1 type and may use 2 or more types together.

The first resin layer, the second resin layer, and the through conductor constituting the multilayer resin layer can function particularly effectively by having a specific correlation with each other.
Among these, it is preferable to have the following correlation between the thickness of the first resin layer and the thickness of the second resin layer. That is, the thickness of the second resin layer is 1/40 to 1/2 of the thickness of the first resin layer (more preferably 1/30 to 1/3, particularly preferably 1/20 to 1/5). ) Is preferable. Within this range, the characteristics of the first resin layer and the characteristics of the second resin layer can be obtained synergistically. That is, the shape retention property as the whole multilayer resin layer can be sufficiently secured. In addition, the through conductor can be reliably formed. Furthermore, excellent bondability and excellent followability are sufficiently exhibited. Moreover, the fluidity | liquidity of the thermoplastic resin at the time of a heating can fully be suppressed. Furthermore, the thickness of the first resin layer is not particularly limited, but is 1000 μm or less (500 μm or less is more preferable, 200 μm or less is more preferable, 2 to 200 μm is still more preferable, 5 to 100 μm is particularly preferable, and 5 to 35 μm is especially preferable. Preferred). The thickness of the second resin layer is preferably an appropriate thickness depending on the thickness of the conductor pattern provided on the wiring board to be bonded and the arrangement area thereof, and is not particularly limited, but is 1000 μm or less (12 to 1000 μm is more). 12 to 200 μm is more preferable, and 20 to 100 μm is particularly preferable.

Moreover, it is preferable to have the following correlation between the thermal expansion coefficient of a 1st resin layer and the thermal expansion coefficient of a penetration conductor. That is, the thermal expansion coefficient in the plane direction of the first resin layer is α ¹ _xy , the thermal expansion coefficient in the thickness direction of the first resin layer is α ¹ _z, and the thermal expansion coefficient of the through conductor is α ^3. In this case, it is preferable that −10 × 10 ⁻⁶ ≦ α ¹ _xy (/ ° C.) ≦ 30 × 10 ⁻⁶ and α ¹ _z ≧ α ³ . Within this range, peeling and delamination between the first resin layer and the second resin layer and between the multilayer resin layer and the wiring board can be more effectively prevented.

In the present invention, the thermal expansion coefficient is determined by cutting out the layers to be measured (first resin layer and second resin layer) into strip-shaped test pieces having a length of 10 mm and a cross-sectional area of 0.2 mm ² , and a tensile load of 0 The linear expansion coefficient measured by a thermal stress strain measurement device (manufactured by Rigaku Corporation, “TMA8310”) after fixing the test piece to the device at 3 g and raising the temperature from room temperature at a rate of 5 ° C./min. Shall. Of the thermal expansion coefficients, α ¹ _xy , α ² _xy, and α ³ each have a resin flow direction (extrusion direction by extrusion formation) in each layer as an X direction and an orthogonal direction as a Y direction. These are the average values of the linear thermal expansion coefficients at 50 ° C. to 150 ° C. in the respective directions. Further, α ¹ _z and α ² _z are respectively the resin flow direction (extrusion direction by extrusion formation) in each layer as the X direction, the orthogonal direction thereof as the Y direction, and orthogonal to both the X direction and the Y direction. Is the linear thermal expansion coefficient in the direction. The shape of the test piece at the time of measuring α ¹ _z and α ² _z is 10 mm long × 2.6 mm wide × 3.8 mm thick. Note that, since α ³ is usually isotropic in thermal expansion coefficient of the through conductor (even if it has a thermal expansion coefficient difference depending on the direction, it is negligibly small), the measurement direction is limited. Not.

The “wiring board” is a board having a conductor pattern on at least one side. Further, this conductor pattern is a conductor pattern electrically connected to the through conductor.
This conductor pattern is a patterned layer having conductivity (that is, usually 3 μΩ · cm or less at normal temperature). The shape, thickness, and the like of the conductor pattern are not particularly limited, but are usually 200 μm or less (preferably 100 μm or less, more preferably 20 μm or less). Furthermore, the conductor material which comprises a conductor pattern is not specifically limited, For example, copper, silver, gold | metal | money, platinum, nickel, tin, lead, and 2 or more types of these etc. are mentioned. These conductive materials may be used alone or in combination of two or more.

In addition, the wiring board usually includes an insulating layer that insulates the conductor pattern. The insulating material constituting the insulating layer is not particularly limited. That is, for example, an organic material or an inorganic material may be used.
Examples of the organic material include a thermoplastic resin contained in the first resin layer and a thermosetting resin contained in the second resin layer. Other than these, bismaleimide / triazine resin, fluororesin, phenol resin, xylene resin, thermosetting PPE (polyphenylene ether) resin, BCB (benzocyclobutene), polynorbornene, and the like can be given. These organic materials may use only 1 type and may use 2 or more types together. Further, this insulating layer is composed of the various fillers and core materials {glass cloth, glass nonwoven fabric, resin (polyamide, etc.) cloth, resin (polyamide, etc.) nonwoven fabric, resin (polyamide, etc.) film, PTFE (polytetrafluoroethylene), etc.} Can be contained. These fillers and core materials may be used alone or in combination of two or more.
Examples of inorganic materials include various ceramic materials (dielectric ceramic materials such as metal titanate, glass ceramic materials, etc.).

  The form of the wiring board is not particularly limited, and may be a single-layer board (including an insulating layer and a conductor pattern formed on one or both sides of the insulating layer), and a multilayer wiring board (insulating two or more layers). Layer and two or more layers of conductive patterns may be alternately stacked). Among these, when the single-layer substrate is used, the effect of using the multilayer resin layer is particularly easily obtained. In particular, the flexible substrate is preferably a flexible flexible substrate. That is, when a flexible substrate is used, a multilayer wiring substrate partially flexible as shown in FIGS. 6 to 9 can be obtained. This board has a structure in which two board parts, ie, a rigid part 200 and a flexible part 300 are connected without using a connector. For this reason, it is possible to obtain a multilayer wiring board particularly excellent in space saving.

  The flexible substrate has flexibility as a whole of the wiring substrate, and usually has flexibility by having a resin portion. This resin part is normally used as an insulating layer. In addition, the flexible substrate includes the insulating layer and a conductor pattern formed on one side or both sides of the insulating layer. That is, for example, the flexible substrate is composed of one insulating layer and a conductor pattern formed on one or both surfaces of this insulating layer.

  The type of the resin constituting the resin portion is not particularly limited, and may be a thermoplastic resin or a thermosetting resin, but is usually a thermoplastic resin because it requires flexibility. As this thermoplastic resin, the various thermoplastic resins mentioned in the first resin layer can be applied as they are. That is, polyimide resin (PEI, thermoplastic polyimide resin, polyamideimide resin, etc.), liquid crystal polymer, polyaryl ketone resin (PEEK, PEK, PEKK, etc.) and the like can be mentioned. These thermoplastic resins may use only 1 type and may use 2 or more types together. Of these thermoplastic resins, polyimide resins are preferred.

Further, the resin part constituting this flexible substrate has a 1% weight loss temperature (measured in the atmosphere using a thermogravimetric measuring device) of 300 ° C. or higher (more preferably 350 ° C. or higher, more preferably 400 ° C. or higher). Preferably there is. Within this range, a multilayer substrate having excellent heat resistance can be obtained.
Further, the glass transition point of the resin portion constituting the flexible substrate is not particularly limited, but is preferably 180 ° C. or higher (more preferably 200 ° C. or higher, still more preferably 250 ° C. or higher). Within this range, a multilayer substrate having particularly excellent heat resistance can be obtained. Furthermore, it is possible to control the curing temperature of the thermosetting resin used for the second resin layer and the temperature range in which an appropriate fluidity of the thermoplastic resin constituting the first resin layer is obtained in an overlapping temperature range. Moreover, the thickness of the resin part which comprises a flexible board | substrate is although it does not specifically limit, Usually, it is 50 micrometers or less.
In addition, about a conductor pattern which comprises the said wiring board, a shape, thickness, a material, etc. are not specifically limited, A conventionally well-known conductor pattern can be used.

  The laminated structure part in the multilayer wiring board of the present invention can include other parts (including other layers and components) in addition to the multilayer resin layer and the wiring board. An example of the other part is a heat sink made of metal. This heat radiating plate is a layer having a function of conducting and radiating heat generated in the multilayer wiring board to the outside in order to prevent the electrical characteristics from being changed due to heat stored in the multilayer wiring board when the multilayer wiring board is used. is there. Although the kind of metal which comprises this heat sink is not specifically limited, Copper and aluminum etc. can be contained as a main component, and copper foil (it consists only of copper) or aluminum foil etc. can be used. The thickness of the heat sink is not particularly limited, but is usually 3 mm or less (preferably 2 mm or less, more preferably 1 mm or less).

  Further, the laminated structure portion can include other portions in addition to the multilayer resin layer, the wiring board, and the heat sink. Examples of other parts include a protective layer 150 such as a resist layer included in a multilayer wiring substrate 100f illustrated in FIG. 8 described later, a plating layer 125 included in a multilayer wiring substrate 100g illustrated in FIG. 9 described later, and the like. In addition, a layer such as a coverlay may be mentioned. These layers may use only 1 type and may use 2 or more types together.

  The multilayer wiring board of the present invention can include other parts in addition to the multilayer structure part. Examples of other parts include various layers such as a resist layer, a plating layer, and a coverlay. Further, connection terminals such as solder bumps and solder balls used for connection to external devices {various components (active components, passive components), other wiring boards} and the like can be mentioned. Furthermore, various electronic components (active component, passive component, conversion component, connection component, etc.), etc. are mentioned. These may use only 1 type and may use 2 or more types together.

Hereinafter, structural examples of the multilayer wiring board of the present invention will be described with reference to FIGS.
[1] Multilayer wiring board 100a shown in FIG.
A multilayer wiring board 100a shown in FIG. 3 is an example of the multilayer wiring board according to the present invention in which the following layers (1) to (7) are stacked in this order from one side to the other side.
(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A wiring board comprising a through conductor 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; the same layer as (2) above.
(5) “Multilayer resin layer 110a”; the same layer as in (3) above.
(6) “Flexible substrate 120”; the same layer as (2) above.
(7) “Other layer 130a”; a layer having the same structure as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.

[2] Multilayer wiring board 100b shown in FIG.
A multilayer wiring board 100b shown in FIG. 4 is another example of the multilayer wiring board of the present invention in which the following layers (1) to (9) are stacked in this order from one surface side to the other surface side. The multilayer wiring board 100b is provided with the following layers (1) to (9) stacked in this order from one surface side to the other surface side.
(1) “Wiring pattern 140”; a layer that can be obtained by patterning a metal film obtained by using both an electroless plating method and an electrolytic plating method by a photolithography method.
(2) “Multilayer resin layer 110b”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on one surface of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer. The second resin layer 112 is disposed on the flexible substrate 120 side of (3) below.
(3) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 arranged on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A wiring board comprising a through conductor 122.
(4) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(5) “Flexible substrate 120”; the same layer as (3) above.
(6) “Multilayer resin layer 110a”; the same layer as in (4) above.
(7) “Flexible substrate 120”; same layer as (3) above.
(8) “Multilayer resin layer 110b”: a layer having the same configuration as in (2) above. The second resin layer 112 is disposed on the flexible substrate 120 side in (7) above.
(9) “Wiring pattern 140”: Same layer as in (1) above.

[3] Multilayer wiring board 100c shown in FIG.
A multilayer wiring board 100c shown in FIG. 5 includes the following layers (1) to (5) stacked in this order from one surface side to the other surface side.
(1) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 arranged on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides A layer comprising a through conductor.
(2) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(3) “Flexible substrate 120”; the same layer as (1) above.
(4) “Multilayer resin layer 110a”; the same layer as in (2) above.
(5) “Flexible substrate 120”; the same layer as (1) above.
In addition, in the through hole formed in the flexible substrate 120 of (1) and (5) in FIG. 5, there is a through conductor 122 made of an inner wall surface conductor layer, and the remaining portion of the through hole other than the inner wall surface conductor layer Is a filling portion formed by plastic deformation and filling of the second resin layer 112 of the multilayer resin layer 110a when the flexible substrate 120 and the multilayer resin layer 110a are pressure-bonded.

[4] Multilayer wiring board 100d shown in FIG.
A multilayer wiring board 100d shown in FIG. 6 includes a rigid portion 200 in which the following layers (1) to (7) are laminated in this order from one surface side to the other surface side, and the following from the one surface side to the other surface side. Each of the layers (3) to (5) includes a flexible portion 300 in which the layers are laminated in this order, and each of the layers (3) to (5) constituting the flexible portion 300 constitutes the rigid portion 200 (3) to ( 5) a multilayer wiring board which is a part of 5). In other words, the multilayer wiring board 100d includes the following layers (1) to (7) stacked in this order from one surface side to the other surface side, and (1) to (2) and (6) to (7 ) Of the flexible portion 300 that is partially absent. Each of these layers is as follows.

(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A layer comprising through conductors 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”: Same layer as above.
(5) “Multilayer resin layer 110a”; the same layer as above.
(6) “Flexible substrate 120”; same layer as above.
(7) “Other layer 130a”; a layer having the same structure as above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.
In the flexible portion 300, the multilayer resin layer 110 a functions as a protective layer for the conductor pattern 123 disposed on both the front and back surfaces of the flexible substrate 120.

[5] Multilayer wiring board 100e shown in FIG.
A multilayer wiring board 100e illustrated in FIG. 7 is a multilayer wiring board in which the flexible substrate 120 in the flexible portion 300 in FIG. 6 includes the conductor pattern 123 only on one side. For this reason, the protective layer of the conductor pattern 123 is formed only on one surface side of the flexible substrate 120.
That is, the multilayer wiring board 100e includes a rigid part 200 in which the following layers (1) to (7) are stacked in this order from one surface side to the other surface side, and the following from the one surface side to the other surface side. (3) to (4) are provided with a flexible portion 300 in which the layers are laminated in this order, and the layers (3) to (4) constituting the flexible portion 300 constitute the rigid portion 200 (3) to ( This is a multilayer wiring board which is a part of 4). In other words, the multilayer wiring board 100e is provided with the following layers (1) to (7) laminated in this order from one surface side to the other surface side, and (1) to (2) and (5) to (7 ) Of the flexible portion 300 that is partially absent. Each of these layers is as follows.

(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A layer comprising through conductors 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; the same layer as (2) above.
(5) “Multilayer resin layer 110a”; the same layer as in (3) above.
(6) “Flexible substrate 120”; the same layer as (2) above.
(7) “Other layer 130a”: a layer having the same configuration as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.

  The multilayer wiring board 100d in FIG. 6 and the multilayer wiring board 100e in FIG. 7 are configured such that the flexible substrate 120 in (4) has the conductor pattern 123 on both sides in the flexible portion 200 or the conductor pattern 123 only on one side. Or depending on the difference. That is, in the multilayer wiring substrate 100d of FIG. 6, the flexible substrate 120 of (4) also has the conductor pattern 123 on both surfaces of the flexible portion 200. For this reason, in order to protect both conductor patterns 123, both the multilayer resin layer 110a of (3) and the multilayer resin layer 110a of (5) are also present in the flexible portion 200.

[6] Multilayer wiring board 100f shown in FIG.
The multilayer wiring board 100f shown in FIG. 8 uses the protective layer 150 formed separately in the flexible part 200 in FIG. 6 without using the multilayer resin layer 110a to protect the conductor pattern 123 of the flexible board 120 in (4). A multilayer wiring board.
That is, the multilayer wiring board 100f includes a rigid portion 200 in which the following layers (1) to (7) are stacked in this order from one surface side to the other surface side, and the following from the one surface side to the other surface side. (8), (4), and (8) are provided with a flexible portion 300 in which the respective layers are laminated in this order, and the flexible substrate (4) constituting the flexible portion 300 constitutes the rigid portion 200. A part of the flexible substrate, (8) is a multilayer wiring substrate which is a protective layer 150 formed separately. Each of these layers is as follows.

(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A layer comprising through conductors 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; the same layer as (2) above.
(5) “Multilayer resin layer 110a”; the same layer as in (3) above.
(6) “Flexible substrate 120”; the same layer as (2) above.
(7) “Other layer 130a”: a layer having the same configuration as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.
(8) “Protective layer 150”; a separate layer for protecting the conductor pattern 123 formed on both surfaces of the flexible substrate 120 of (4) above. As the protective layer 150, a resist layer, a coverlay, or the like can be used.

[7] Multilayer wiring board 100g shown in FIG.
The multilayer wiring board 100g shown in FIG. 9 is a plating having excellent oxidation resistance formed in advance in the flexible part 200 in FIG. 6 without using the multilayer resin layer 110a to protect the conductor pattern 123 of the flexible board 120 in (4). A multilayer wiring board using layers.
That is, the multilayer wiring board 100g is protected by a rigid portion 200 in which the following layers (1) to (7) are laminated in this order from one surface side to the other surface side, and the plating layer (4). The flexible substrate 300 includes the flexible portion 300 that includes only the flexible substrate, and the flexible substrate (4) that constitutes the flexible portion 300 is a multilayer wiring board that is a part of the flexible substrate (4) that constitutes the rigid portion 200. Each of these layers is as follows.

(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A layer comprising through conductors 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A layer provided with a through conductor 122 and a plating layer 125 formed on the surface of the conductor pattern 123.
(5) “Multilayer resin layer 110a”; the same layer as in (3) above.
(6) “Flexible substrate 120”; the same layer as (2) above.
(7) “Other layer 130a”: a layer having the same configuration as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.

The plating layer 125 can be obtained by plating the surface of the conductor pattern 123 of the flexible substrate 120 in advance before the multilayer wiring substrate 100g is laminated. Examples of the metal material excellent in oxidation resistance constituting the plating layer include noble metals other than silver, such as gold, platinum, and palladium, and nickel. These metal materials may use only 1 type and may use 2 or more types together.
In FIG. 9, the structure in which the plating layer 150 is formed on the flexible substrate 120 and then laminated is illustrated. However, after all the layers are laminated, the plating layer 150 is formed only on the exposed conductor pattern 123. May be.

[8] Multilayer wiring board 100h shown in FIG.
A multilayer wiring board 100h shown in FIG. 10 is an example in which a high dielectric constant resin layer 124 is used instead of the resin portion 121 constituting the flexible board 120 of (6) in the multilayer wiring board 100a of FIG. As the high dielectric constant resin layer 124, a thermoplastic resin containing a high dielectric ceramic filler (alumina filler, titanate filler, etc.), a cured thermosetting resin, or the like can be used. These may use only 1 type and may use 2 or more types together.
A multilayer wiring board 100h shown in FIG. 10 is an example of the multilayer wiring board according to the present invention in which the following layers (1) to (7) are stacked in this order from one side to the other side.
(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A wiring board comprising a through conductor 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; the same layer as (2) above.
(5) “Multilayer resin layer 110a”; the same layer as in (3) above.
(6) “Flexible substrate 120”; a dielectric constant resin layer 124 containing a thermoplastic resin in which an alumina filler is dispersed, a conductor pattern 123 disposed on both surfaces of the first resin layer 121, and front and back conductors A wiring board including a through conductor 122 that electrically connects the pattern 123.
(7) “Other layer 130a”; a layer having the same structure as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (6) above.

In the multilayer wiring board 100h illustrated in FIG. 10, only the resin layer 121 constituting the flexible board 120 in (6) is the high dielectric constant resin layer 124. However, in addition to this, (2), (4 ) And (6), a flexible substrate 120 in which at least one resin layer 121 is replaced with the high dielectric constant resin layer 124 can be obtained. Furthermore, each of the flexible substrates 120 can be replaced with a rigid wiring substrate having a ceramic layer capable of exhibiting a high dielectric constant.
Similarly, in each of the multilayer wiring boards of FIGS. 3 to 9 and FIGS. Can be replaced.

[9] Multilayer wiring board 100i shown in FIG.
A multilayer wiring board 100 i illustrated in FIG. 11 is an example of a multilayer wiring board including a heat sink 160. The multilayer wiring board 100i is an example of the multilayer wiring board of the present invention in which the following layers (1) to (11) are laminated in this order from one surface side to the other surface side.
(1) “Other layer 130a”; a first resin layer 131 containing a thermoplastic resin and having a through-hole 133 formed therein, and a first resin layer containing a thermosetting resin disposed on one surface of the first resin layer 131. A layer comprising two resin layers 132. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A wiring board comprising a through conductor 122.
(3) “Multilayer resin layer 110a”; a first resin layer 111 containing a thermoplastic resin, and a second resin layer 112 containing a thermosetting resin disposed on both surfaces of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer.
(4) “Flexible substrate 120”; the same layer as (2) above.
(5) “Other layer 130 b”; provided with a first resin layer 131 containing a thermoplastic resin and a second resin layer 132 containing a thermosetting resin disposed on one surface of the first resin layer 131. layer. The second resin layer 132 is disposed on the flexible substrate 120 side in (2) above.
(6) “Heat sink 160”: a layer made of copper and having excellent thermal conductivity.
(7) “Other layer 130b”; a layer having the same configuration as in (3) above. The second resin layer 132 is disposed on the flexible substrate 120 side of (6) below.
(8) “Flexible substrate 120”; the same layer as (2) above.
(9) “Multilayer resin layer 110a”; the same layer as in (3) above.
(10) “Flexible substrate 120”; the same layer as (2) above.
(11) “Other layer 130a”; a layer having the same configuration as in (1) above. The second resin layer 132 is disposed on the flexible substrate 120 side in (10) above.
The heat sink 160 provided in the multilayer wiring board 100i is not patterned, and is not connected to the conductor pattern 123 provided in the flexible board 120 sandwiching the heat sink 160.

[10] Multilayer wiring board 100j shown in FIG.
A multilayer wiring board 100j illustrated in FIG. 12 is another example of the multilayer wiring board including the heat sink 160. This multilayer wiring board 100j includes (1) “other layer 130a” of (1) to (7) from one surface side to the other surface side; a first resin layer containing a thermoplastic resin and having a through-hole 133 formed therein 131 and a second resin layer 132 containing a thermosetting resin disposed on one surface of the first resin layer 131. The second resin layer 132 is disposed on the flexible substrate 120 side of (2) below.
(2) “Flexible substrate 120”; electrically connecting the first resin layer 121 containing a thermoplastic resin, the conductor pattern 123 disposed on both surfaces of the first resin layer 121, and the conductor patterns 123 on the front and back sides. A wiring board comprising a through conductor 122.
(3) “Multilayer resin layer 110b”; a first resin layer 111 containing a thermoplastic resin and a second resin layer 112 containing a thermosetting resin disposed on one surface of the first resin layer 111; A layer provided with a through conductor 113 provided through the first resin layer and the second resin layer. The second resin layer 112 is disposed on the flexible substrate 120 side in (2) above.
(4) “Heat dissipation plate 160”; patterned copper 161 and thermoplastic resin 162 filled in through holes formed by patterning (which constitutes the first resin layer 111 constituting the multilayer resin layer 110b) The same) and a layer with excellent thermal conductivity. Further, the heat radiating plate 160 includes the conductor pattern 123 provided in each of the flexible substrates 120 of (2) and (6) below, and the multilayer resin layer 110b of (3) and (7) below. The through conductor 113 and the wiring pattern 140 are electrically connected.
(5) “Multilayer resin layer 110b”; a layer having the same configuration as in (3) above. It arrange | positions at the flexible substrate 120 side of following (6).
(6) “Flexible substrate 120”; the same layer as (2) above.
(7) “Other layer 130a”; the same layer as the other layer 130a in (1) above.

In addition, in each of the multilayer wiring boards 100a to 100j shown in FIGS. 3 to 12, each of the multilayer wiring boards 100a to 100j corresponds to a laminated structure portion according to the present invention.
Further, in the through holes 133 formed in the other layers 130a of the multilayer wiring boards 100a and 100d to 100j shown in FIG. 3 and FIGS. A pin or the like can be arranged.
Further, in each of the multilayer wiring boards 100a to 100j shown in FIGS. 3 to 12, the through conductors 123 included in the wiring board (flexible board) 120 are each formed by filling a resin (conductive paste) containing a conductive filler ( It may be a resin-containing penetrating conductor that may be cured afterwards if necessary, or may be a plated metal penetrating conductor, or a metal inner wall layer formed on the inner wall surface of the through hole. And a through conductor in which the remainder of the through hole is filled with resin. These penetration conductors may use only 1 type and may use 2 or more types together.

Also, the multilayer resin layers 110a and 110b included in each of the multilayer wiring boards 100a to 100j illustrated in FIGS. 3 to 12 and the through conductors included in the wiring board 120 are stacked vias (see FIGS. 1 to 6; the through conductors are stacked on each other). The structure may be formed as a non-stacked via (see FIG. 7, a structure in which through conductors are not stacked on each other), or these may be mixed.
Further, in FIGS. 3 to 12, an example in which the flexible substrate 120 is used as each wiring substrate 120 is illustrated, but one or more of these wiring substrates 120 may be rigid substrates.

[2] Manufacturing method of multilayer wiring board The manufacturing method of the multilayer wiring board of the present invention is not particularly limited, but can be manufactured by the following method.
That is, a first resin layer containing a thermoplastic resin, a second resin layer containing a thermosetting resin provided on at least one surface of the first resin layer, and the first resin layer and the second resin layer A multilayer resin layer having a through conductor penetrating through the resin layer;
A laminating step of laminating a wiring board having a conductor pattern on at least one side;
In the lamination step, the multilayer resin layer and the wiring board are laminated on the second resin layer side and the conductor pattern side, and the through conductor and the conductor pattern are electrically connected. A method of manufacturing a multilayer wiring board, wherein the structure portion is formed.

When using the said manufacturing method, it can be set as the following each one or the other method further.
(1) The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The laminated structure section includes two wiring boards, and the first wiring board of the wiring boards, the multilayer resin layer, and the second wiring board of the wiring boards are in this order. Laminated,
The multilayer resin layer and the first wiring board are laminated on the second resin layer side of one surface and the conductor pattern side included in the first wiring board,
The multilayer resin layer and the second wiring board are laminated on the second resin layer side of the other surface and the conductor pattern side included in the second wiring board,
And the conductor pattern with which this 1st wiring board is provided, and the conductor pattern with which this 2nd wiring board is provided are electrically connected via this penetration conductor,
In this manufacturing method, the multilayer resin layer and the wiring board are laminated together.

(2) The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The laminated structure portion includes a heat sink made of metal, and is provided with the wiring board, the multilayer resin layer, and the heat sink stacked in this order.
In this manufacturing method, the multilayer resin layer, the wiring board, and the heat dissipation plate are laminated together.

  According to these multilayer wiring board manufacturing methods, it is possible to manufacture a multilayer wiring board with high design efficiency, excellent bonding with other layers, and high manufacturing efficiency. That is, since a plurality of layers including an electrical interlayer connection can be stacked at once because a multilayer resin layer is used, a high degree of design freedom can be obtained. In order to obtain interlayer conduction as in the prior art, there is no inconvenience of forming through holes penetrating all layers after multilayering and forming through holes in unnecessary layers. In addition, since the second resin layer containing the thermosetting resin excellent in bondability is provided on the outer surface side, the excellent bondability can be exerted on a wide range of materials to be bonded. Wide selection range and high design freedom. Furthermore, since it can also laminate | stack collectively as mentioned above, it is excellent in manufacturing efficiency. Further, it is not necessary to use a core substrate as in the case of using only a prepreg, and a coreless multilayer wiring substrate can be obtained.

  In the multilayer wiring board of the present invention, the multilayer resin layer is a thermosetting resin before the thermosetting resin is cured, whereas the second resin layer contains the thermosetting resin. Different in. In other cases, the multilayer resin layer can be applied as it is. Moreover, the thermosetting resin which comprises the said thermosetting resin is applicable as it is also about a thermosetting resin.

As described above, the multilayer resin layer includes the first resin layer (containing a thermoplastic resin) and the second resin layer (containing a thermosetting resin). The second resin layer contains a thermosetting resin and can exhibit strong bondability. This bondability can be effectively exhibited especially for a wiring board provided with a resin insulating layer. Further, the thermosetting resin is superior in conformity to the shape of the uneven surface than the thermoplastic resin. Usually, sufficient fluidity and pressure are required to cause the thermoplastic resin to follow the uneven surface between conductor patterns having a thickness of several to several tens of micrometers. However, when the fluidity is increased (the heating temperature is increased) and the pressurizing pressure is increased, the thermoplastic resin is unintentionally spread in the plane direction. On the other hand, even though the thermosetting resin is excellent in followability to a small uneven surface, even when the amount of the resin is small as in the second resin layer of the present invention because it is cured, The spread in the plane direction can be controlled.
However, the second resin layer having excellent performance is also difficult to obtain sufficient shape retention if only the second resin layer is present alone, and a penetrating conductor is imparted to the layer consisting only of the second resin layer. Can not do it. On the other hand, by providing the first resin layer, it is possible to have a through conductor while having shape retaining property as a whole and exhibiting excellent bonding property and shape following property at the time of lamination.

  On the other hand, if only the first resin layer is heated at the time of lamination, it expands due to the characteristics of the thermoplastic resin. Moreover, precise temperature control is required, and when the temperature is excessively high, the fluidity of the first resin layer increases rapidly. However, the multilayer resin layer used in this method has a second resin layer. Since this layer contains a thermosetting resin, it has the property of being cured and shrunk when heated (such as laminating heating), and can suppress the expansion of the first resin layer. Further, as the fluidity of the first resin layer increases, the fluidity of the second resin layer decreases, and the multi-layer resin layer can be maintained at a high temperature. In particular, the fluidity in the planar direction of the first resin layer at high temperatures (such as during lamination heating) is excellent in suppressing the excessive increase in fluidity in the planar direction. Therefore, it is possible to manufacture with excellent lamination accuracy and shape stability. Moreover, in the obtained multilayer wiring board, the excellent heat resistance by a thermosetting resin is exhibited.

Further, as described in the multilayer wiring board of the present invention, the resin part constituting the wiring board preferably has a 1% weight loss temperature of 300 ° C. or higher, and further has a glass transition point of 180 ° C. or higher. More preferably. If it is this range, in the temperature range which overlaps the curing temperature of the thermosetting resin used for the 2nd resin layer, and the temperature range in which the moderate fluidity of the thermoplastic resin which comprises the 1st resin layer is obtained. Can be controlled.
Furthermore, as described in the multilayer wiring board of the present invention, the thickness of the second resin layer is preferably 1/40 to 1/2 of the thickness of the first resin layer. More preferably, it is 1/30 to 1/3, and still more preferably 1/20 to 1/5. Within this range, the characteristics of the first resin layer and the characteristics of the second resin layer can be obtained particularly synergistically. That is, the shape retention property as the whole multilayer resin layer can be sufficiently secured. In addition, the through conductor can be reliably formed. Furthermore, excellent bondability and excellent followability are sufficiently exhibited. Moreover, the fluidity | liquidity of the thermoplastic resin at the time of a heating can fully be suppressed. The preferred range of this thickness is as described above (in the multilayer resin layer, the correlation of each layer after curing is described, but since there is almost no change in the layer thickness before and after curing, it is also applicable to each resin layer before curing. ) The same applies to the preferred ranges of the thickness of the first resin layer and the thickness of the second resin layer.

In the lamination step, heating is usually performed. By heating, the thermosetting resin contained in the second resin layer of the multilayer resin layer is cured, and the thermosetting resin contained in the first resin layer has adhesiveness and fluidity. Can be given. The temperature in this heating is not particularly limited, and is preferably set appropriately depending on the type of thermosetting resin and thermoplastic resin to be used, but is usually 180 ° C. or higher. In this range, the thermosetting resin constituting the second resin layer can be sufficiently cured while obtaining sufficient fluidity of the thermosetting resin constituting the first resin layer.
Furthermore, it is preferable to apply pressure in addition to the above heating. The degree of pressurization is not particularly limited, but is usually 1 MPa or more. In this range, the through conductor and the wiring pattern can be reliably electrically connected, and the followability of the multilayer resin layer to the bonded layer can be sufficiently exhibited.

In the above manufacturing method, when the multilayer resin layer has the second resin layer on both surfaces of the first resin layer, the first wiring substrate and the multilayer resin are laminated by laminating the wiring substrates on the front and back of the multilayer resin layer. A laminated structure portion in which the layers and the second wiring board are laminated in this order can be obtained collectively.
In this case, the wiring board and the multilayer resin layer are arranged (positioned and laminated) in the order described above, and for example, heated (and may be further pressurized) to collectively form a laminated structure. Part can be obtained. At the same time, the conductor pattern provided in the first wiring board and the conductor pattern provided in the second wiring board can be electrically connected via the through conductor provided in the multilayer resin layer.
As the lamination conditions in this lamination process, the above-mentioned lamination conditions (heating temperature, pressure, etc.) can be applied as they are.
The same can be done when two or more of the multilayer resin layer and the wiring board are laminated. That is, for example, the wiring board and the multilayer resin layer are arranged alternately, such as the first wiring board, the multilayer resin layer, the second wiring board, the multilayer resin layer, and the third wiring board. And can be laminated.

Further, in the above manufacturing method, when the multilayer resin layer has the second resin layer on both sides of the first resin layer, the wiring board is laminated on one side of the multilayer resin layer, and the heat sink is laminated on the other side. Thereby, the laminated structure part by which the wiring board, the multilayer resin layer, and the heat sink were laminated | stacked in this order can be obtained collectively.
In this case, the wiring board, the multilayer resin layer, and the heat radiating plate are arranged (positioned and laminated) in the order described above, and then collectively heated, for example, (may be further pressurized). Thus, a laminated structure part can be obtained. At the same time, the conductor pattern provided on the wiring board and the heat radiating plate can be electrically connected via the through conductor provided in the multilayer resin layer (not necessarily connected).
As the lamination conditions in this lamination process, the above-mentioned lamination conditions (heating temperature, pressure, etc.) can be applied as they are. In addition, the heat sink in the said multilayer wiring board can be used as it is for the said heat sink.

Hereinafter, the present invention will be described specifically by way of examples.
[1] Manufacture of multilayer wiring board shown in FIG. 4 (1) Multilayer resin layer 110a
First resin layer 111; a layer made of a resin thin film (product name “IBUKI”, manufactured by Mitsubishi Chemical Corporation) with PEEK and PEI as main components and adjusted to a thickness of about 50 μm.
Second resin layer 112: a layer obtained by laminating a semi-cured thermosetting resin layer having a thickness of about 10 μm mainly composed of a thermosetting polyimide resin on both surfaces of the first resin layer.
Through-hole conductor 113; a through-hole (through-hole) penetrating the entire multilayer body including the first resin layer and the second resin layer is formed to a diameter of 120 μm by a laser drilling machine. Then, after penetrating through paste the paste for penetration conductor containing silver coat copper powder into the above-mentioned through hole by screen printing, the penetration conductor formed by hardening.

(2) Flexible substrate 120
A double-sided copper-clad laminate having about 12 μm thick electrolytic copper foil on both sides of about 25 μm thick polyimide is prepared. Thereafter, a pattern and a via are formed by a known method to obtain a flexible substrate.

(3) Lamination process The multilayer resin layers 110a and the flexible substrate 120 are alternately laminated and pressed in the lamination direction (bonding direction) while heating to a temperature of 230 ° C. or higher under a vacuum of 20 Torr (≈2666 Pa) or less. Apply pressure (4 MPa) (vacuum hot press).
(4) Wiring pattern 140
A metal film obtained by using both the electroless plating method and the electrolytic plating method is formed by patterning using a photolithography method.
In this way, the multilayer wiring board shown in FIG. 4 is obtained.

  The present invention can be widely used in the field of electronic components. Further, the wiring board of the present invention includes a normal wiring board such as a mother board, a flip chip wiring board, a CSP wiring board, a semiconductor element mounting wiring board such as an MCP wiring board, an antenna switch module wiring board, and a mixer module. This is suitable for a module wiring board such as a wiring board for PLL, a wiring board for PLL module, and a wiring board for MCM.

It is typical sectional drawing of an example of a multilayer resin layer. It is typical sectional drawing of the other example of a multilayer resin layer. It is typical sectional drawing of an example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention. It is typical sectional drawing of the other example of the multilayer wiring board of this invention.

Explanation of symbols

  100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h, 100i, 100j; multilayer wiring board, 110a, 110b; multilayer resin layer, 111; first resin layer (resin layer containing thermoplastic resin), 112 Second resin layer (resin layer containing thermosetting resin), 113; penetrating conductor, 120; wiring board (flexible wiring board), 121; resin layer (resin portion) of wiring board, 122; penetrating conductor of wiring board 123; Wiring board conductor pattern 124; High dielectric constant resin layer of wiring board 125; Plating layer 130a, 130b; Other layers 140; Conductor pattern 150; Protection layer 160; Heat sink 200; Rigid Part 300; flexible part.

Claims (9)

A first resin layer containing a thermoplastic resin, a second resin layer containing a thermosetting resin provided on at least one surface of the first resin layer, and the first resin layer and the second resin layer A multilayer resin layer having a through conductor penetrating through
A wiring board having a conductor pattern on at least one side,
The multilayer resin layer and the wiring board are laminated on the second resin layer side and the conductor pattern side, and have a laminated structure portion in which the through conductor and the conductor pattern are electrically connected. A multilayer wiring board characterized by that. The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The laminated structure section includes two wiring boards, and the first wiring board of the wiring boards, the multilayer resin layer, and the second wiring board of the wiring boards are in this order. Laminated,
The multilayer resin layer and the first wiring board are laminated on the second resin layer side of one surface and the conductor pattern side included in the first wiring board,
The multilayer resin layer and the second wiring board are laminated on the second resin layer side of the other surface and the conductor pattern side included in the second wiring board,
The multilayer wiring board according to claim 1, wherein a conductor pattern provided in the first wiring board and a conductor pattern provided in the second wiring board are electrically connected through the through conductor. The multilayer resin layer has the second resin layer on both sides of the first resin layer,
The multilayer wiring board according to claim 1, wherein the laminated structure portion includes a heat sink made of metal, and the wiring board, the multilayer resin layer, and the heat sink are stacked in this order.   The multilayer wiring board according to claim 1, wherein the wiring board is a flexible board.   The multilayer wiring board according to any one of claims 1 to 4, wherein the resin portion constituting the wiring board has a 1% weight loss temperature of 300 ° C or higher.   The multilayer wiring board according to claim 5, wherein the resin portion constituting the wiring board has a glass transition point of 180 ° C. or higher.   The multilayer wiring board according to claim 1, wherein a thickness of the second resin layer is 1/40 to 1/2 of a thickness of the first resin layer. The thermal expansion coefficient in the planar direction of the first resin layer is α ¹ _xy , the thermal expansion coefficient in the thickness direction of the first resin layer is α ¹ _z, and the thermal expansion coefficient of the through conductor is α ³
−10 × 10 ⁻⁶ ≦ α ¹ _xy (/ ° C.) ≦ 30 × 10 ⁻⁶ ,
The multilayer wiring board according to claim ¹ , wherein α ¹ _z ≧ α ³ . When the thermal expansion coefficient in the planar direction of the second resin layer is α ² _xy, and the thermal expansion coefficient in the thickness direction of the second resin layer is α ² _z ,
10 × 10 ⁻⁶ ≦ α ² _xy (/ ° C.) ≦ 60 × 10 ⁻⁶ ,
The multilayer wiring board according to claim 1, wherein 10 × 10 ⁻⁶ ≦ α ² _z (/ ° C.) ≦ 60 × 10 ⁻⁶ .

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