JP2000200976A - Multilayer printed wiring board and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer printed wiring board which is laminated and integrated by thermal fusion of a film-like insulator and has high insulation reliability even when a high-density circuit pattern is formed. provide. SOLUTION: 65 to 35% by weight of a polyarylketone resin such as polyetheretherketone having a crystal melting peak temperature of 260 ° C. or more, and an amorphous polyetherimide resin 3
5 to 65% by weight, having a glass transition temperature of 150 to
230 ° C., and the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc is represented by the formula (I). Filling the conductive paste to form a heat-fusible film for interlayer connection of the laminated electric circuit, heat-sealing the thermoplastic resin composition by laminating a conductor foil on one or both sides as shown in formula (II) After that, a circuit is formed on the conductive foil to provide a film-shaped wiring board, and a plurality of laminated materials composed of the heat-fusible film for interlayer connection are alternately laminated, and the thermoplastic resin composition constituting each layer is represented by the formula A multilayer printed wiring board is manufactured by heat fusion as shown in (III).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a multilayer printed wiring board and a method for manufacturing the same, and more particularly, to a multilayer printed wiring board having an insulating layer made of a thermoplastic resin and a method for manufacturing the same.

[0002]

2. Description of the Related Art In order to respond to recent demands for smaller, lighter, faster, and more sophisticated electronic devices, the degree of integration of semiconductors mounted on printed wiring boards has increased, the number of pins has increased, and the spacing between semiconductors ( Pitch) has decreased, and the demand for higher functionality in multilayer printed wiring boards has been increasing day by day.

The multilayer printed wiring board used in such a situation is made of a resin multilayer board using a prepreg in which fibers such as epoxy resin are impregnated as an insulating material, and is formed on a copper-clad laminate. In order to enable connection between each layer of the electric circuit, a via hole (Via hole;
It has a through hole having a hole diameter of about 0.3 to 1.2 mm called a plated through hole into which no component is inserted) or a through hole.

[0004] The formation density of through-holes in a multilayer printed wiring board has been increasing in accordance with the demand for higher functionality as described above.
Forming a through hole by drilling in order to cope with a high wiring density of, for example, 50 to 150 μm in the wiring pitch has been an obstacle to a demand for a higher density circuit of a multilayer printed wiring board.

To cope with such a problem, a multilayer printed wiring board having a build-up layer in which a through-hole such as a via hole having a minute hole diameter of a micron unit is formed has been developed.

[0006] A multilayer printed wiring board having a build-up layer is a resin film with a copper foil in which a small-diameter via hole is formed by laser processing or etching using a normal wiring board in which a required number of through holes are formed in advance as a base (substrate). (Build-up layer) is stacked on the base and bonded and integrated, or all layers are formed by laminating build-up layers in which via holes of small diameter are formed.

As shown in FIGS. 2 (a), 2 (b) and 2 (c), a multi-layer printed wiring board in which all six layers are formed by build-up layers is obtained by first impregnating a non-woven fabric with an epoxy resin. A prepared hole 11 penetrating through both surfaces of the prepreg thus formed is formed by laser processing, a conductive paste 12 is filled in the prepared hole by a printing method, laminated with a copper foil by a vacuum hot press, and the prepreg and the conductive paste are cured.

Next, a copper foil is etched to form a circuit pattern 13, and a double-sided wiring board 14 is formed as a core layer, and a prepreg 15 is formed by separately drilling a pilot hole 11 and filling with a conductive paste 12. And copper foil 16
Are aligned on both surfaces of the core layer, and are again subjected to hot pressing and patterning (forming a circuit pattern by etching) to obtain a four-layer substrate 17 as shown in FIG. To manufacture.

Then, as shown in FIG. 2C, after the copper foil on the surface of the four-layer substrate 17 is etched to form the circuit patterns 13 on both sides, the prepreg 18 and the copper foil 19 are further hot-pressed. By repeating the patterning process, a printed wiring board having six layers has been manufactured. Incidentally, an eight-layer printed wiring board can also be manufactured by adding two layers to the six-layer wiring board by repeating the steps of hot pressing and patterning the prepreg and copper foil.

[0010]

However, it is not easy for the above-mentioned conventional multilayer printed wiring board to ensure the adhesion state between the core layer and the build-up layer on which the printed wiring is formed, and the circuit pattern has a micron unit. In the case of a high-density wiring formed at a wiring pitch, the insulating material may not be completely filled between the wirings, and there is a problem that the so-called “embeddability of the inner layer circuit” of the insulating material is likely to be deteriorated.

Such a problem is related to the production of a product having non-uniform characteristics such as insulating properties, and the reliability of the printed wiring board and the reduction in product yield due to the occurrence of defective products (reduction in production efficiency) ).

As described above, since the embedding property of the inner layer circuit having a high wiring density by the insulating material is uncertain, the materials of the multilayer printed wiring board exceeding four layers are collectively laminated and integrated by heat fusion. As a result, it has not been possible to manufacture products with high insulation reliability.

[0013] The use of a liquid insulating material can considerably reduce the problem of embedding the inner layer circuit. However, it takes a long time to apply and dry the insulating material. There are also various problems, such as an increase in ease of use.

Accordingly, an object of the present invention relating to a multilayer printed wiring board is to solve the above-mentioned problems, and to provide a multilayer printed wiring board which is laminated and integrated using a heat-fusible film-like insulator, has a high wiring. An object of the present invention is to provide a circuit in which the wiring is reliably buried with an insulating material even when the circuit has a densified inner layer circuit.

Another object of the invention relating to a method of manufacturing a multilayer printed wiring board is to improve a manufacturing method by build-up of a multilayer printed wiring board using a film-like insulator, and to provide good embedding of an insulating material in an inner layer circuit. Provided is an efficient manufacturing method in which the insulation reliability of circuits with high wiring density is high, and moreover, when multiple layers of laminated materials are stacked, they can be integrated in a single heat and pressure step by heat fusion. It is to be.

[0016]

In order to solve the above-mentioned problems, according to the invention relating to a multilayer printed wiring board, a polyaryl ketone resin 65 to 3 having a crystal melting peak temperature of 260 ° C. or higher is used.
A film-like insulator consisting of 5% by weight and 35 to 65% by weight of an amorphous polyetherimide resin is provided, a double-sided through hole is formed in the film-like insulator, and a conductive paste is filled in the through-hole. A heat-fusible film for interlayer connection of a laminated electric circuit is formed, a conductor foil is heat-sealed on one or both surfaces of the heat-fusible film for interlayer connection, and a circuit is formed to provide a film-shaped wiring board. A multilayer printed wiring board was obtained by laminating a plurality of laminated materials composed of a film-shaped wiring board and the above-mentioned heat-fusible film for interlayer connection and integrating them by heat-sealing.

Further, the glass transition temperature measured when the thermoplastic resin forming the film-like insulator in the multilayer printed wiring board is raised by differential scanning calorimetry has a glass transition temperature of 15%.
0 to 230 ° C. and is a thermoplastic resin composition in which the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature increase satisfies the relationship represented by the following formula (I): It was a printed wiring board. Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35.

Alternatively, the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during heating of the thermoplastic resin forming the film-like wiring board in the multilayer printed wiring board is represented by the following formula (II). ) Is a thermoplastic resin composition that satisfies the relationship shown in (1). Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5.

Alternatively, the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during heating of the thermoplastic resin forming the multilayer printed wiring board in the multilayer printed wiring board is represented by the following formula (III). The multilayer printed wiring board which is a thermoplastic resin composition satisfying the relationship shown in (1) is obtained. Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7.

In order to solve the above-mentioned problems relating to the manufacturing method, according to the present invention, the crystal melting peak temperature 260
65 to 35% by weight of a polyaryl ketone resin having a temperature of at least
35 to 65% by weight of an amorphous polyetherimide resin, having a glass transition temperature of 150 to 230 ° C. measured when the temperature is raised by differential scanning calorimetry, and a heat of crystal fusion ΔHm and a crystal being heated. Heat of crystallization generated by crystallization
A film-like insulator is formed from a thermoplastic resin composition whose relationship with Hc satisfies the relationship represented by the following formula (I), a double-sided through hole is formed in the film-like insulator, and a conductive material is formed in the through-hole. Filling the paste to form a heat-fusible film for interlayer connection of a laminated electric circuit, and superposing a conductive foil on one or both surfaces of the heat-fusible film for interlayer connection, the thermoplastic resin composition has the following formula ( After heat-sealing so as to satisfy the relationship shown in II), a circuit is formed on the conductive foil to provide a film-like wiring board, and the film-like wiring board and the lamination comprising the heat-fusible film for interlayer connection A plurality of materials are alternately stacked, and the thermoplastic resin composition constituting each layer is represented by the following formula:
This is a method of manufacturing a multilayer printed wiring board, which comprises performing heat fusion so as to satisfy the relationship shown in (III). Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7.

The multilayer printed wiring board of the present invention configured as described above has a film-like insulator in which a predetermined amount of a crystalline polyarylketone resin and an amorphous polyetherimide resin are blended. Satisfactorily satisfies the adhesiveness with a conductor foil, heat resistance, mechanical strength and electrical insulation required for insulating materials for printed circuit boards.

The heat-fusible film for interlayer connection of the laminated electric circuit is formed of the above-mentioned insulating thermoplastic resin material, and the opening of the double-sided through-hole is electrically connected by the conductive paste in the double-sided through-hole. As a contact point, a portion of an electric circuit arranged and formed on one side or both sides of the film is conducted in a layer thickness direction.

The thermoplastic resin forming such a film-like insulator or a film-like wiring board has a glass transition temperature of 150 to 230 ° C., and has a heat of crystal fusion ΔHm and is generated by crystallization during heating. Heat of crystallization ΔH
Since the relationship with c satisfies the relationship represented by the above formula (I) or formula (II), the progress of crystallization is adjusted to an appropriate range, for example, relatively less than 250 ° C. Demonstrates excellent adhesive strength by heat fusion at low temperatures.
Therefore, multi-layer printed wiring boards having more than four build-up layers can be integrally laminated by heating and pressing. When a conductor foil whose surface is roughened is used as the conductor foil, the adhesive strength is further increased.

Further, the thermoplastic resin composition satisfying the relations represented by the formulas (I) and (II) has a low elastic modulus in a bonding temperature region with the conductor foil, so that it can be filled even in a fine wiring pitch. .
Therefore, the embedding property of the inner layer circuit of the multilayer printed wiring board using the heat-fusible film for interlayer connection and the film-like insulator, that is, the insulating property is improved.

According to the method of manufacturing a multilayer printed wiring board of the present invention, a plurality of laminated materials composed of a film-shaped wiring board and the above-mentioned heat-fusible film for interlayer connection are alternately laminated to form a thermoplastic resin composition constituting each layer. Heat fusion is performed so that the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature rise satisfies the relationship represented by the above formula (III). In this case, the thermoplastic resin composition after the heat fusion becomes an insulating layer having solder heat resistance to withstand 260 ° C. because the crystallinity of the polyarylketone resin is appropriately advanced, and The bonding strength with the conductor foil is also increased, and the conductive circuit formed by etching the conductor foil is also firmly adhered to the film-like insulator, so that delamination hardly occurs.

In the above method for producing a multilayer printed wiring board, when the conductor foil is laminated on one side or both sides of the heat-fusible film for interlayer connection and heat-sealed, the crystal of the thermoplastic resin composition after heat-sealing is used. In the method of performing heat fusion so that the relationship between the heat of fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature rise satisfies the relationship represented by the above formula (II), a film-like wiring is again formed after the heat fusion. Even when a plurality of laminated materials composed of a substrate and the heat-fusible film for interlayer connection are alternately stacked, and the heat-sealing is performed by heating and pressing all at once, the thermoplastic resin has an elastic modulus in a bonding temperature region with the conductive foil. Decreases,
An appropriate low-viscosity resin is surely filled even in a fine wiring pitch, and a good product having extremely high embedding property of the inner layer circuit, that is, extremely high insulation reliability can be manufactured.

Since the film-like insulator and the conductor foil are bonded by heat without interposing an adhesive such as an epoxy resin between the layers, various properties such as heat resistance, chemical resistance, and electrical properties are bonded. The excellent properties of the insulating layer are fully utilized without being influenced by the properties of the agent. Also, since there is no step of applying and drying an adhesive or other liquid laminated material during the manufacturing process, a method of manufacturing a multilayer printed wiring board with high manufacturing efficiency can be achieved.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a multilayer wiring board and a method of manufacturing the same according to the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 (a ₁ ) and ₁ (b), or FIGS. 1 (a ₂ ) and 1 (b), respectively, showing two manufacturing steps, the multilayer printed wiring board according to the present invention has a predetermined composition. And a film-like insulator 1 made of a thermoplastic resin composition having thermal characteristics, a hole 2 penetrating through both surfaces by laser processing.
And a conductive paste 3 is filled in the holes 2 to form a heat-fusible film 4 for interlayer connection of a laminated electric circuit.
Further, both surfaces of the heat-fusible film 4 for interlayer connection (FIG. 1)
a ₁ ) or one side (a _{2 in} the figure) of a conductive foil thermally bonded by a vacuum heat press machine, and a conductive circuit 5 is formed by subtractive method except for an unnecessary portion of the conductive foil. It is obtained by laminating a plurality of laminated materials selected from the wiring substrates 6, 7 and the heat-fusible film 4 for interlayer connection, and laminating and integrating them by heat fusion.

FIG. 1B shows a multilayer printed wiring board in which conductive circuits 5 are formed in four layers by solid lines.
₁ ) and (b) in FIG.
It is also possible to manufacture a multilayer printed wiring board having multiple layers or more layers.

In order to manufacture a film-like insulator,
A polyaryl ketone resin and an amorphous polyetherimide resin are blended to prepare a predetermined crystalline resin represented by the formula (I). Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35.

When the conductor foil is heat-sealed to the film-like insulator, the glass transition point (Tg) of the thermoplastic resin composition is exceeded, but the crystal melting peak temperature (Tc) is not exceeded. Is heated to a predetermined temperature range in which is maintained, and a film-like substrate is produced by heat-sealing a conductive foil that preferably maintains the properties represented by the formula (II) in the thermoplastic resin composition. Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5.

The method of forming the conductive circuit on the conductive foil is as follows.
Although a well-known subtractive method can be adopted, an additive method can also be adopted. Incidentally, as a specific example of the subtractive method, a dry film made of an ultraviolet curable resin is laminated on a copper foil, and then a pattern film formed with a cutout mold of a conductive circuit is exposed to ultraviolet light in a state where the pattern film is in close contact with the dry film. Exposure, then remove the pattern film and uncured dry film, perform etching with a ferric chloride solution to remove the copper foil in unnecessary portions of the conductive circuit, and then immerse in a sodium hydroxide solution The remaining dry film on the copper foil is removed to form a conductive circuit.

When a plurality of laminated materials composed of a film-like wiring board and the above-mentioned heat-fusible film for interlayer connection are laminated and heat-sealed at once, the heat of crystal fusion of the thermoplastic resin composition constituting each layer is considered. Thermal fusion is performed so that the relationship between ΔHm and the amount of heat of crystallization ΔHc generated by crystallization during temperature rise satisfies the relationship represented by the formula (III). Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 In this case, the thermoplastic resin composition is heated to around the crystal melting peak temperature (Tc) (for example, 230 to 250 ° C.). As a result, reliable heat fusion becomes possible and crystallization of the thermoplastic resin composition proceeds, so that a multilayer printed wiring board having excellent solder heat resistance can be manufactured.

In the present invention, the polyaryl ketone resin, which is the first component constituting the film-like insulator, is a thermoplastic resin having an aromatic nucleus bond, an ether bond and a ketone bond in its structural unit, that is, phenyl ketone. And a phenyl ether.

Typical examples of the polyarylketone resin include polyetherketone, polyetheretherketone, and polyetherketoneketone. In the present invention, polyetheretherketone represented by the following formula 1 is used. It can be used as suitable.

[0037]

Embedded image

The amorphous polyetherimide resin which is the second component constituting the film-like insulator is an amorphous thermoplastic resin having an aromatic nucleus bond, an ether bond and an imide bond in its structural unit. In the present invention, a polyetherimide resin represented by the following formula 2 can be applied.

[0039]

Embedded image

The film-like insulator used in the present invention is composed of a composition obtained by blending the above two kinds of heat-resistant resins at a predetermined ratio, that is, the thermoplastic resin composition has a crystal melting peak temperature of 260 ° C. It is composed of 65 to 35% by weight of the above-mentioned polyarylketone resin and 35 to 65% by weight of the amorphous polyetherimide resin, and has a glass transition temperature of 150 to 2 as measured when the temperature is raised by differential scanning calorimetry.
30 ° C.

The reason for limiting the mixing ratio as described above is as follows.
If the polyarylketone resin is blended in a large amount exceeding 65% by weight, or if the blending ratio of the polyetherimide resin is 35
If the compounding ratio is small, the crystallization rate of the composition becomes too high and its crystallinity becomes too high, making it difficult to form a multilayer substrate by heat fusion, or shrinking the volume due to crystallization ( This is because the dimensional change) increases and the reliability of the circuit board decreases.

If the content of the crystalline polyallyl ether ketone resin is less than 35% by weight or the content of the amorphous polyetherimide resin exceeds 65% by weight, the crystallization speed of the composition becomes too slow, and , And even if the crystal melting peak temperature is 260 ° C. or higher, the solder heat resistance decreases, which is not preferable.

The thermal characteristic of the film-like insulator, which is an important control factor in the present invention, is expressed by the following formula (I) as to the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during heating. It is to satisfy the relationship shown. The thermal characteristic represented by the formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 (ΔHm−ΔHc) / ΔHm is expressed by JI
The measured values of two transition heats appearing in the DSC curve when the temperature is raised by differential scanning calorimetry according to S K 7121 and JIS K 7122, the heat of crystal fusion ΔHm (J / g) and the heat of crystallization ΔHc (J / g) Is calculated from the value of

The value of the equation (ΔHm−ΔHc) / ΔHm also depends on the type and molecular weight of the raw material polymer and the compounding ratio of the composition, but greatly affects the molding and processing conditions of the film-shaped insulator. I do. That is, when the film is formed into a film, the raw material polymer is melted and then cooled immediately, whereby the value of the above formula can be reduced.
Further, these numerical values can be controlled by adjusting the heat history in each step. The heat history here refers to the temperature of the film-shaped insulator and the time during which the temperature has been reached, and the higher the temperature, the larger the numerical value tends to be.

Regarding the thermal characteristics of the conductor foil and the film-like insulator before thermal fusion, it is preferable that the value represented by the above formula (I) is as small as possible. 0.35 before thermal fusion with conductor foil
If the ratio exceeds, the crystallinity is already high, and the crystallization further proceeds during the heat-sealing for multi-layering, and the adhesive strength is undesirably reduced.

The relationship represented by the above formula (II) is obtained by measuring after heat-sealing a copper-clad laminated substrate obtained by heat-sealing a conductor foil on at least one surface of a film-like insulator in the process of manufacturing a multilayer printed wiring board. It is based on.

When the value represented by the formula (II) exceeds 0.5, the crystallinity is already high, and the crystallization proceeds further at the time of heat-sealing for multi-layering, whereby the adhesive strength decreases. Further, it is necessary to perform heat fusion with the conductor foil at a high temperature, which is not preferable in terms of manufacturing efficiency.

Then, the thermal characteristics of the film-like insulator after the thermal fusion after the multilayering satisfy the relation of the following formula (III). Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 Because the value of the above formula (III) is as low as less than 0.7, the crystallization of the insulating layer is insufficient, and This is because heat resistance (usually 260 ° C.) cannot be maintained.

The film-like insulator used in the present invention generally has a thickness of 25 to 300 μm, and its production method is, for example, a known film-forming method such as an extrusion casting method using a T-die or a calendering method. What is necessary is just to employ | adopt and it is not necessary to employ | adopt a manufacturing method especially limited. In addition, it is preferable to employ the extrusion casting method using a T-die from the viewpoint of film forming property and stable productivity. The molding temperature of the extrusion casting method is appropriately adjusted depending on the flow characteristics and film forming characteristics of the composition, but is generally from the melting point of the composition to 430 ° C. or less.

The resin composition constituting the film-shaped insulator used in the present invention may contain other resins and other additives to such an extent that the effect of the present invention is not impaired. Examples include a heat stabilizer, an ultraviolet absorber, a light stabilizer, a colorant, a lubricant, a flame retardant, and an inorganic filler.
Further, the surface of the film-shaped insulator may be subjected to embossing or corona treatment for improving the handling properties and the like.

Examples of the conductive foil used in the present invention include metal foils having a thickness of about 8 to 70 μm, such as copper, gold, silver, aluminum, nickel, and tin. Among them, the metal foil to be applied is particularly preferably a copper foil whose surface has been subjected to a chemical conversion treatment such as a black oxidation treatment. The conductor foil is
In order to enhance the bonding effect, it is preferable to use a material whose contact surface (overlapping surface) with the film-shaped insulator is chemically or mechanically roughened in advance. Specific examples of the conductor foil subjected to the surface roughening treatment include a roughened copper foil that has been electrochemically treated when producing an electrolytic copper foil.

When the conductor foil is superimposed on one or both surfaces of the film-like insulator and heat-sealed under heating and pressing conditions, for example, a hot pressing method or a heat laminating roll method, a method combining these, or other well-known methods Can be adopted.

In the case of multi-layering, it is preferable that the thickness of the layer made of the film-like insulator is at least twice the total thickness of the conductor foil. If it is less than twice, the resin embedding property into the conductor circuit portion tends to be insufficient when the layers are multilayered.

[0054]

EXAMPLES AND COMPARATIVE EXAMPLES First, Production Examples 1 to 3 of a film insulator satisfying the conditions of the film insulator of the present invention.
The production methods of Reference Examples 1 and 2 and the physical properties thereof are described below.

[Production Example 1 of Film Insulator] Polyether ether ketone resin (Victrex: PEE)
K381G) (in the following text or in Tables 1 and 2, P
Abbreviated as EEK. ) 60% by weight and a polyetherimide resin (manufactured by General Electric Company: Ultem-1)
000) (PEI in the following text or in Tables 1 and 2)
Abbreviated. ) 40% by weight was dry blended. This mixed composition was extruded to produce a film insulator having a thickness of 25 μm.

[Production Example 2 of Film Insulator] Production Example 1
, A film-like insulator was produced in the same manner except that the mixing ratio of the mixed composition was 40% by weight of PEEK and 60% by weight of PEI.

[Production Example 3 of Film Insulator] Production Example 1
, A film-like insulator was produced in the same manner except that the mixing ratio of the mixed composition was 30% by weight of PEEK and 70% by weight of PEI.

[Reference Examples 1 and 2 of Film Insulator] In Production Example 1, the mixing ratio of the mixed composition was changed to PEEK100.
Each film-shaped insulator was manufactured in the same manner except that the weight% (Reference Example 1) or the PEI 100% by weight (Reference Example 2) was used.

In order to examine the physical properties of the film-like insulator obtained in the above Production Examples and Reference Examples, the following (1) and (2)
The following items were measured or calculated values were calculated from the measured values.
These results are summarized in Table 1.

(1) Glass transition temperature (° C.), crystallization temperature (° C.), crystal melting peak temperature (° C.) A 10 mg sample was heated according to JIS K7121 using a Perkin Elmer DSC-7. Speed 1
Each of the above temperatures when the temperature was raised at 0 ° C./min was determined from a thermogram.

(2) (ΔHm−ΔHc) / ΔHm According to JIS K7122, 10 mg of a sample was used, and the heating rate was set to 1 using DSC-7 manufactured by Perkin Elmer.
The heat of crystal fusion ΔHm (J / g) and the heat of crystallization ΔHc (J / g) were determined from the thermogram when the temperature was raised at 0 ° C./min, and the value of the above equation was calculated.

[0062]

[Table 1]

Example 1 Thickness 25 obtained in Production Example 1
The film-shaped insulator having a thickness of μm was subjected to an opening process for an inner via hole using a laser, and the hole was filled with a conductive paste agent using a screen printer. After the conductive paste was sufficiently dried, an electrolytic copper foil having a 12 μm-thick electrochemically roughened surface was laminated on both surfaces of the film-like insulator, and 760 mm in a vacuum atmosphere.
Pressing temperature 200 ° C, pressing pressure 30kg / cm in Hg
^{2. A} double-sided copper-clad laminate was prepared by heat fusion under the conditions of a press time of 10 minutes.

The above (2) (ΔHm−ΔHc) / ΔHm measurement test was carried out on the film-like insulator of the double-sided copper-clad laminate thus produced by the same method as described above.

The adhesive strength of the obtained double-sided copper-clad laminate was examined by the method (3) described later, and the results are shown in Table 2.

A circuit pattern was formed on the obtained double-sided copper-clad laminate by a subtractive method, and two wiring boards were formed by etching a conductive circuit. The thickness 2 obtained in Production Example 1 between the two wiring boards
Stacked in a state shown in FIG. 1 (a ₁ ) with a 5 μm film-shaped insulator interposed therebetween, and heated by a pin lamination method under a vacuum atmosphere at 760 mmHg at a pressing temperature of 220 ° C., a pressing pressure of 30 kg / cm ² and a pressing time of 20 minutes. By fusion, a four-layer multilayer printed wiring board was manufactured.

With respect to the obtained multilayer printed wiring board,
(2) In addition to conducting a measurement test of (ΔHm−ΔHc) / ΔHm, the bonding strength between the copper foil circuit and the film-like insulator at room temperature is checked by the test method of (3) below, and the presence or absence of delamination is scanned. Observation was made with a scanning electron microscope (method (5) below), and the solder heat resistance was examined by the test method (4) below. The results are shown in Table 2.

(3) Adhesive Strength The peel strength of the copper foil of the FPC blank was measured in accordance with the normal peel strength of JIS C6481, and the average value was shown in kgf / 10 cm.

(4) Solder heat resistance According to the normal solder heat resistance of JIS C6481,
After floating in a solder bath at 60 ° C. for 10 seconds with the copper foil side of the test piece in contact with the solder bath, take out from the bath and allow it to cool to room temperature, and visually observe the presence or absence of swelling or peeling,
The quality was evaluated.

(5) The multilayer printed wiring board is embedded in epoxy resin, and a sample for section observation is prepared by a precision cutting machine.
The cut surface was observed with a scanning electron microscope (SEM), and the presence or absence of delamination between the film-like insulator and the conductive circuit made of copper foil was evaluated.

[0071]

[Table 2]

Example 2 In Example 1, the production temperature was set to 225 ° C. when producing a double-sided copper-clad laminate using Production Example 2 as a film-like insulator, A four-layer printed wiring board was prepared in the same manner as in Example 1 except that the pressing conditions were changed to a temperature of 240 ° C. and a breath time to 30 minutes, and the evaluations of Tests (3) to (5) were carried out in Table 2. Also described in the inside.

Example 3 In Example 1, a circuit pattern was formed from a double-sided copper-clad laminate, and five wiring boards having conductive circuits formed by etching were prepared. A 10-layer multilayer printed wiring board was manufactured in the same manner as in Example 1, except that the obtained film-shaped insulators were stacked and stacked and heat-sealed at once by a pin lamination method.

[Comparative Example 1] A four-layer multilayer printed wiring board was manufactured in the same manner as in Example 1 except that the press temperature at the time of manufacturing the double-sided copper-clad laminate was 215 ° C. Table 2 also shows the evaluations of the tests (3) to (5).

Comparative Example 2 The procedure of Example 2 was repeated except that the pressing temperature of the multilayer printed wiring board having four layers was changed to 230 ° C. and the pressing time was changed to 10 minutes.
Of multi-layer printed wiring board and test it
The evaluations of (3) to (5) are also shown in Table 2.

Comparative Example 3 In Example 1, the production temperature was changed to 240 ° C. and the press time was changed to 20 minutes in the production of the double-sided copper-clad laminate using Production Example 3 as the film-like insulator. Except for the above, a four-layered multilayer printed wiring board was produced in the same manner as in Example 1, and tests (3) to (5) for this
Are also shown in Table 2.

As is clear from the results in Table 2, the adhesive strength of the double-sided copper-clad laminate of Example 1 was 0.7 kgf / 10
cm, which is (ΔHm−ΔHc) / ΔH
The value of m was also an appropriate value of 0.31. The value of (ΔHm−ΔHc) / ΔHm when laminating four multilayer printed wiring boards is also an appropriate value of 0.95, and the adhesive strength is 1.4 kg.
It was a good value of f / 10 cm. As a result of the solder heat resistance test, no swelling or peeling was observed on the substrate, no delamination was observed even by SEM observation of the four-layered multilayer printed wiring board, and the resin wrapped around the circuit pattern (filling). Amount) was good, and generation of voids was not observed at all.

The adhesive strength of the double-sided copper-clad laminate of Example 2 was a good value of 1.3 kgf / 10 cm, the result of the solder heat resistance test was good, and the S
No delamination was observed at all by EM observation, and the resin wrapping around the circuit pattern was good.

Also, in Example 3, the adhesive strength was a good value, and the results of the solder heat resistance test showed that no swelling or peeling was observed on the substrate, and that the S
No delamination was observed at all by EM observation, the resin wrapped around the circuit pattern (filling amount) was good, and no voids were observed. In addition, the number of steps is considerably smaller than that of a conventional build-up type multilayer printed wiring board manufacturing method, and the number of manufacturing days and manufacturing cost can be reduced. In addition, since the quality of the substrate can be determined at the stage of the double-sided copper-clad laminate before the multilayer press, the yield is greatly improved.

On the other hand, the four-layer printed wiring board of Comparative Example 1 was inferior in the adhesion between the layers, and the solder heat resistance was poor because swelling and peeling were observed.

The four-layer printed wiring board of Comparative Example 2
Although there was adhesion between the layers, the solder heat resistance was poor.

In Comparative Example 3, the adhesive strength between the copper foil and the film of the double-sided copper-clad laminate was as low as 0.2 kgf / 10 cm, and the circuit peeled off in the etching step.

[0083]

As described above, the multilayer printed wiring board according to the present invention is obtained by blending a predetermined amount of a predetermined polyarylketone resin and a predetermined amount of an amorphous polyetherimide resin, Forming a film-shaped insulator with a plastic resin composition, forming a heat-fusible film for interlayer connection of a laminated electric circuit with the film-shaped insulator, and forming a circuit-shaped film-shaped wiring board on this, Since these are stacked and integrated by heat fusion,
The thermoplastic resin composition of each layer exhibits excellent adhesive strength when melted by heating, has no delamination between layers even in a multilayer printed wiring board exceeding four layers, and has a required solder heat resistance due to the heat resistance of the thermoplastic resin composition. It shows the nature.

Further, since the thermoplastic resin composition satisfying the relationship represented by the formula (I) has a low elastic modulus in a bonding temperature region with the conductive foil, the thermoplastic resin composition has a small space between fine wiring pitches when heat-sealing each layer. A multilayer printed wiring board with good insulation properties of an inner layer circuit formed with a high wiring density filled with an insulating material.

The method for manufacturing a multilayer printed wiring board according to the present invention is a method for manufacturing a multilayer printed wiring board using a film-like insulator made of a crystalline thermoplastic resin having predetermined thermal characteristics. The embedding property of the wiring density in the inner layer circuit is improved, so that a circuit with high insulation reliability can be manufactured. In addition, when the laminated material is laminated in multiple layers, it can be laminated and integrated by heat fusion in a single heating and pressing process. So
There is an advantage that it is an efficient manufacturing method.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a manufacturing process of a multilayer printed wiring board.

FIG. 2 is a schematic view showing a manufacturing process of a conventional multilayer printed wiring board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Film-shaped insulator 2 Hole 3 and 12 Conductive paste 4 Heat-fusible film for interlayer connection 5 Conductive circuit 6 and 7 Film-shaped wiring board 11 Preparatory hole 13 Circuit pattern 14 Double-sided wiring board 15 and 18 Pre-preg 16 and 19 Copper foil 17 4 layer board

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Jun Takagi 5-8, Mitsuya-cho, Nagahama-shi, Shiga Prefecture Mitsubishi Plastics Co., Ltd. Inside Nagahama Plant Co., Ltd. (72) Koichiro Taniguchi 5-8, Mitsuya-cho, Nagahama-shi, Shiga Prefecture Mitsubishi Plastics Inside Nagahama Plant Co., Ltd. (72) Kaoru Nomoto 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Masashi Aichi 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation F term (reference) 4J002 CH09W CM04X GQ01 5E346 AA42 CC08 CC09 CC32 EE13 EE19 EE38 FF18 GG27 GG28

Claims (9)

[Claims] 1. A film insulator comprising 65 to 35% by weight of a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and 35 to 65% by weight of an amorphous polyetherimide resin, And a conductive paste is filled into the through-hole to form a heat-fusible film for interlayer connection of the laminated electric circuit, and a conductor is formed on one or both surfaces of the heat-fusible film for interlayer connection. A film-like wiring board is provided by heat-sealing the foil and forming a circuit, and a plurality of laminated materials composed of the film-like wiring board and the heat-fusible film for interlayer connection are alternately stacked and integrated by heat-sealing. Multilayer printed wiring board. 2. The multilayer printed wiring board according to claim 1, wherein the conductor foil is a surface-roughened conductor foil. 3. The multilayer printed wiring board according to claim 1, wherein the polyaryl ketone resin is a polyether ether ketone resin. 4. The thermoplastic resin forming the film-shaped insulator has a glass transition temperature of 150 to 230 ° C. measured when heated by differential scanning calorimetry, and has a heat of crystal fusion ΔHm and a temperature during heating. Heat of crystallization Δ generated by crystallization
The multilayer printed wiring board according to any one of claims 1 to 3, wherein the thermoplastic resin composition has a relationship with Hc satisfying a relationship represented by the following formula (I). Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 5. The relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during temperature rise of the thermoplastic resin forming the film-like wiring board is represented by the following formula (II). It is a thermoplastic resin composition that satisfies
3. The multilayer printed wiring board according to any one of 3. Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 6. The relationship between the heat of crystallization ΔHm of the thermoplastic resin forming the multilayer printed wiring board and the heat of crystallization ΔHc generated by crystallization during heating is represented by the following formula (III). 2. A thermoplastic resin composition to be filled.
4. The multilayer printed wiring board according to any one of items 1 to 3. Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 7. A polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher, 65 to 35% by weight, and an amorphous polyetherimide resin, 35 to 65% by weight, which are measured when the temperature is raised by differential scanning calorimetry. The glass transition temperature is 150 to 230 ° C., and the relationship between the heat of crystal fusion ΔHm and the heat of crystallization ΔHc generated by crystallization during the temperature rise satisfies the relationship represented by the following formula (I): Forming a film-like insulator with a resin composition, forming a through-hole on both sides of the film-like insulator, and filling a conductive paste in the through-hole to form a heat-fusible film for interlayer connection of a laminated electric circuit. Then, after laminating a conductor foil on one or both sides of the heat-fusible film for interlayer connection, the thermoplastic resin composition is heat-sealed so as to satisfy the relationship represented by the following formula (II),
A circuit is formed on the conductive foil to provide a film-like wiring substrate, and a plurality of laminated materials composed of the film-like wiring substrate and the heat-fusible film for interlayer connection are alternately laminated to form a thermoplastic resin composition constituting each layer. A method for manufacturing a multilayer printed wiring board, comprising heat-sealing a product so as to satisfy a relationship represented by the following formula (III). Formula (I): [(ΔHm−ΔHc) / ΔHm] ≦ 0.35 Formula (II): [(ΔHm−ΔHc) / ΔHm] ≦ 0.5 Formula (III): [(ΔHm−ΔHc) / ΔHm] ≧ 0.7 8. The method for producing a multilayer printed wiring board according to claim 7, wherein the conductor foil to be laminated on one or both sides of the heat-fusible film for interlayer connection is a conductor foil having a roughened surface. 9. The method for producing a multilayer printed wiring board according to claim 7, wherein the polyaryl ketone resin is a polyether ether ketone resin.