JPH0890713A - Production of metal clad laminated sheet - Google Patents

Abstract

PURPOSE: To produce a metal clad laminated sheet having a desired dielectric constant corresponding to the planned circuit of a printed wiring board and contributing to the miniaturization of the printed wiring board and facilitating the production of the circuit. CONSTITUTION: A metal clad laminated sheet is produced by arranging metal foil on the surface of a laminate formed by stacking a plurality of prepregs having different dielectric constants. In this case, the dielectric constant range of the prepregs is 2-20 and the difference between the dielectric constants of them is 2-10 and the dielectric constant of the substrate layer of the laminated sheet is 5-9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a metal foil-clad laminate used for a printed wiring board for communication equipment, for example.

[0002]

2. Description of the Related Art A plurality of prepregs in which a glass base material is impregnated with a resin varnish are stacked, a metal foil is disposed on the surface, and a metal-clad laminate is obtained by heating and pressing. The printed wiring board in which a circuit is formed by etching this metal-clad laminate is used by mounting it on various electric devices. Among these printed wiring boards, the permittivity is an important characteristic in the circuit design of printed wiring boards for high frequency applications such as communication equipment. Therefore, a material having a dielectric constant corresponding to the designed circuit of the printed wiring board is required. Further, in the circuit design, there is a relationship between the permittivity and the size of the printed wiring board, that is, the permittivity increases as the size of the printed wiring board decreases, and the range of the permittivity is determined by the size of the device. There is a situation where it will be done. For example,
In order to reduce the size of a printed wiring board using a material having a dielectric constant of 4.0 to 2/3, it is necessary to use a material having a dielectric constant of 9.0. Further, there is a relationship between the dielectric constant and the circuit width that the circuit width becomes narrower as the dielectric constant increases. Therefore, if the permittivity becomes high and the circuit becomes thin, it is difficult to manufacture the printed wiring board. Therefore, a printed wiring board having a permittivity suitable for practically easy circuit accuracy of about ± 100 μm is required. In the metal-clad laminate used for the above-mentioned printed wiring board for high-frequency applications, a material that can be downsized in a range where circuits can be easily manufactured and has a subdivided predetermined dielectric constant is demanded. There is.

[0003]

In order to obtain the permittivity of the above metal-clad laminate within a predetermined range, it is necessary to prepare various types of prepregs depending on the permittivity because various types of base materials and resins are required. It is difficult to cause waste. There is also a method of preparing only the resin amount of the prepreg to be used, but its preparation width is small, and if the resin amount is too small, the adhesive strength is reduced, and if it is too large, the variation in plate thickness tends to be large,
There is a limit only in the range of the resin amount of the prepreg.

The present invention has been made in view of the above facts, and an object of the present invention is to have a desired dielectric constant in accordance with a circuit for which a printed wiring board is designed, and An object of the present invention is to provide a method of manufacturing a metal-clad laminate which is easy to miniaturize and to manufacture a circuit.

[0005]

A method for manufacturing a metal-clad laminate according to a first aspect of the present invention is characterized in that a metal foil is placed on the surface of a laminate in which a plurality of prepregs having different permittivities are stacked and heated. A method for producing a metal-clad laminate by pressurization, wherein the prepreg has a dielectric constant in a range of 2 or more and 20 or less, and a difference in dielectric constant is 2 or more and 10 or less, and a dielectric constant of a substrate layer of the laminate. Is 5 or more and 9 or less.

A method of manufacturing a metal-clad laminate according to claim 2 of the present invention is the method of manufacturing a metal-clad laminate according to claim 1, wherein the plurality of prepregs have a dielectric loss tangent of 0.01.
It is characterized by being 50 or less.

A method for manufacturing a metal-clad laminate according to claim 3 of the present invention is the method for manufacturing a metal-clad laminate according to claim 1 or 2, wherein the laminate has a dielectric constant of 2 or more and 5 or less. And a prepreg having a dielectric constant of 9 or more and 20 or less.

The present invention will be described in detail below. In the present invention, a metal foil is placed on the surface of a laminate in which a plurality of prepregs having different dielectric constants are stacked, and heated and pressed. The prepreg is a state in which a base material is impregnated with a resin varnish and the impregnated resin is semi-cured. Examples of the resin used in the resin varnish include epoxy resin, fluorine resin, polyphenylene oxide, polyimide resin and the like alone, modified compounds and mixtures thereof. The resin varnish contains, as necessary, a curing agent, a reaction initiator, a filler, a solvent and the like together with the above resin. The base material is not particularly limited, and examples thereof include glass, nonwoven fabric, mat, paper, and a combination thereof, and the glass base material is excellent in heat resistance and the like for high density of circuits. preferable.
Examples of the metal foil include single, alloy, and composite foils of copper, aluminum, nickel, etc., and generally copper foil is generally used. The laminated body may have a multi-layer structure in which a circuit board is arranged between prepregs. By the above heating and pressing, a metal-clad laminate having a substrate layer in which the resin is completely cured can be obtained.

In the present invention, the dielectric constants of the plurality of prepregs are in the range of 2 or more and 20 or less, the difference in the dielectric constant is 2 or more and 10 or less, and the dielectric constant of the substrate layer of the laminate is It is limited to the range of 5 or more and 9 or less.

When manufacturing a circuit using the above-mentioned laminated board, there is a relation between the dielectric constant and the size of the printed wiring board that the larger the dielectric constant is, the smaller the size of the printed wiring board is. If it is large, the printed wiring board can be made small. On the other hand, since there is a relationship between the dielectric constant and the circuit width that the circuit width becomes narrower as the dielectric constant becomes larger, an extremely fine and dense circuit is required as the dielectric constant becomes higher, which is a problem in manufacturing a printed wiring board. However, problems such as increased defects occur. When the dielectric constant of the substrate layer of the laminated plate is in the range of 5 or more and 9 or less, the printed wiring board can be downsized and the circuit accuracy can be practically easily adjusted to about ± 100 μm.

The dielectric constant of the plurality of prepregs is 2 or more 2
When the difference between the dielectric constants is 0 or less and the dielectric constant difference is 2 or more and 10 or less, a fine predetermined dielectric constant can be dealt with by the combination of the above prepregs. The desired permittivity of the laminate determines the proportion of these prepregs that make up the laminate. At that time, if a prepreg having a dielectric constant of 2 or more and 5 or less and a prepreg having a dielectric constant of 9 or more and 20 or less are used, it is easier to combine the substrate layers having a dielectric constant of 5 or more and 9 or less. Further, the dielectric loss tangent of the prepreg is preferably 0.0150 or less, more preferably 0.0100 or less. When the dielectric loss tangent is 0.0150 or less, the transmission loss when an AC voltage is applied is small, and it is suitable for a high-frequency printed wiring board.

The metal-clad laminate obtained according to the present invention is designed by using prepregs having different permittivities in the range of 2 or more and 20 or less and a difference in permittivity of 2 or more and 10 or less. Since the dielectric constant of the substrate layer of the laminated plate is set in the range of 5 or more and 9 or less according to the circuit, the printed wiring board can be downsized and the circuit can be easily manufactured.

The metal-clad laminate has a circuit formed by etching a metal foil and is used as a printed wiring board for communication equipment.

[0014]

According to the method of manufacturing a metal-clad laminate according to any one of claims 1 to 3, the prepreg has a dielectric constant in the range of 2 to 20 and a difference in the dielectric constant of 2 to 10 inclusive. Since prepregs having different permittivities are used, the permittivity of the substrate layer of the laminate is set in the range of 5 or more and 9 or less depending on the circuit to be designed depending on the ratio of these prepregs forming the laminate. Therefore, it is possible to obtain a metal-clad laminate in which a printed wiring board can be miniaturized and a circuit can be easily manufactured.

[0015]

EXAMPLES Next, examples and comparative examples of the present invention will be described.
The dielectric constant and the dielectric loss tangent were measured based on JIS-C6481 under the condition of a frequency of 1 MHz.

Example 1 The following two types of prepreg were used as the prepreg.
The prepreg a is a resin varnish made of polyphenylene oxide (Noryl PX97 manufactured by Japan GE Co., Ltd.).
01) 30 parts by weight (hereinafter referred to as “part”), 5 parts of styrene-butadiene block copolymer (Soaprene T406 manufactured by Asahi Kasei Corporation), 35 parts of crosslinkable monomer (TAIC manufactured by Nippon Kasei Co., Ltd.), reaction initiator ( A blend of 1 part by Nippon Oil & Fats Co., Ltd., PH25B) was used, and E glass having a thickness of 0.1 mm (manufactured by Asahi Schwabel Co., Ltd., dielectric constant 7.2) was used as a glass substrate. The resin varnish was impregnated into the glass base material to obtain a prepreg a.
The resin amount of the prepreg a was 55% by weight. This prepreg a had a dielectric constant of 3.5 and a dielectric loss tangent of 0.0027.

The resin varnish used for the prepreg b is the same resin varnish as the prepreg a, and the glass base material is a high dielectric constant glass having a thickness of 0.1 mm (manufactured by Asahi Schwabel Co., Ltd., dielectric constant 11.5). Using. The resin varnish was impregnated into the glass base material to obtain a prepreg b. Prepreg b
The amount of resin was 55% by weight. This prepreg b had a dielectric constant of 8.0 and a dielectric loss tangent of 0.0029.

The four prepregs a and the four prepregs b were alternately laminated to form a laminated body. Copper foil is laminated on both surfaces of this laminate as a metal foil, and the temperature is 200 ° C. and the pressure is 30 kg / c.
A metal-clad laminate was obtained by heating and pressing at m ² for 60 minutes. The substrate layer of this metal-clad laminate had a dielectric constant of 5.3 and a dielectric loss tangent of 0.0030.

Example 2 A metal-clad laminate was prepared in the same manner as in Example 1 except that 6 prepregs b obtained in Example 1 and 8 prepregs a were provided on each side of the prepregs a. I got a plate. The substrate layer of this metal-clad laminate had a dielectric constant of 6.5 and a dielectric loss tangent of 0.0030.

Example 3 As the prepreg, the prepreg a obtained in Example 1 and the prepreg c produced under the following conditions were used. Prepreg c
Is, as a resin varnish, 30 parts of polyphenylene oxide (manufactured by Japan GE Corporation, Noryl PX9701), 5 parts of styrene-butadiene block copolymer (manufactured by Asahi Kasei Corporation, Sorprene T406), a crosslinkable monomer (manufactured by Nippon Kasei Co., Ltd., TAIC) 35 parts, reaction initiator (manufactured by NOF CORPORATION, PH25B) 1 part, and titanium oxide 150 parts were used as a glass substrate, and E glass having a thickness of 0.1 mm (manufactured by Asahi Schwabel Co., Ltd. ,
A dielectric constant of 7.2) was used. The resin varnish was impregnated into the glass base material to obtain a prepreg c. The resin amount of the prepreg c was 80% by weight. This prepreg c had a dielectric constant of 10.5 and a dielectric loss tangent of 0.0030.

The above four prepregs a and four prepregs c were alternately laminated to form a laminated body. Copper foil was laminated on both surfaces of this laminate, and a metal-clad laminate was obtained in the same manner as in Example 1 below. The substrate layer of this metal-clad laminate had a dielectric constant of 6.0 and a dielectric loss tangent of 0.0030.

Example 4 As prepregs, prepreg d and prepreg e produced under the following conditions were used. The prepreg d is a resin varnish made of epoxy resin (Toto Kasei Co., Ltd., YD
B-500) 160 parts, epoxy resin (Toto Kasei Co., Ltd., YDCN-220) 30 parts, dicyandiamide (manufactured by Nippon Carbide Co., Ltd.) 3 parts as a curing agent, 2 ethyl 4-methylimidazole (2E4MZ: as a curing accelerator). Shikoku Kasei Co., Ltd.) 0.1 part was used. As the glass substrate, E glass having a thickness of 0.1 mm (manufactured by Asahi Schwabel Co., Ltd., dielectric constant 7.2) was used. The resin varnish was impregnated into the glass base material to obtain a prepreg d. The resin amount of the prepreg d was 50% by weight. The prepreg d had a dielectric constant of 4.8 and a dielectric loss tangent of 0.0130.

For the prepreg e, the same resin varnish as the prepreg d was used as the resin varnish, and the glass base material was a high dielectric constant glass (manufactured by Asahi Schwabel Co., Ltd., dielectric constant 11.5) having a thickness of 0.1 mm. Using. The resin varnish was impregnated into the glass base material to obtain a prepreg e. Prepreg e
The amount of resin was 40% by weight. This prepreg e had a dielectric constant of 10.0 and a dielectric loss tangent of 0.0110.

4 sheets of the prepreg d and 4 sheets of the prepreg e were alternately laminated to form a laminated body. A copper foil is laid on both surfaces of this laminate, and the temperature is 170 ° C. and the pressure is 30 kg / cm ² for 60 minutes.
It was heat-pressed for minutes to obtain a metal-clad laminate. The substrate layer of this metal-clad laminate has a dielectric constant of 8.3 and a dielectric loss tangent of 0.012.
It was 5.

Example 5 Four prepregs c and four prepregs d were alternately laminated to form a laminated body. Copper foil was laminated on both surfaces of this laminate, and a metal-clad laminate was obtained in the same manner as in Example 1 below. The substrate layer of this metal-clad laminate has a dielectric constant of 7.7 and a dielectric loss tangent of 0.
It was 0085.

Example 6 A metal-clad laminate was obtained in the same manner as in Example 1 except that six prepregs c and eight prepregs d were provided on each side of the prepregs, for a total of eight prepregs. The substrate layer of this metal-clad laminate has a dielectric constant of 8.8 and a dielectric loss tangent of 0.00.
It was 60.

Example 7 Copper circuits were formed on both surfaces of the metal-clad laminate obtained in Example 1 to obtain an inner layer wiring board. A laminate obtained by stacking two prepregs d and two prepregs e obtained in Example 4 was provided on both surfaces of the inner layer wiring board, and copper foil was laid on both outer surfaces thereof. Then, heating and pressing were performed under the same conditions as in Example 4 to obtain a multilayer metal-clad laminate. This multilayer metal-clad laminate had three substrate layers, the inner layer having a dielectric constant of 5.3 and a dielectric loss tangent of 0.0025, and the outer layer having a dielectric constant of 8.3 and a dielectric loss tangent of 0.0125. .

Comparative Example 1 Eight prepregs d were laminated to form a laminate. Copper foil is laid on both surfaces of this laminate, and the temperature is 170 ° C. and the pressure is 30 kg / c.
A metal-clad laminate was obtained by heating and pressing at m ² for 60 minutes. The substrate layer of this metal-clad laminate had a dielectric constant of 4.8 and a dielectric loss tangent of 0.0130.

Circuits were formed using the metal-clad laminates of Examples 1-7 and Comparative Example 1. By comparing with the printed wiring board of Comparative Example 1, the degree of miniaturization of the size of the printed wiring board having the same function as the circuit of the printed wiring board of Comparative Example 1 was obtained. 3 from the size of the printed wiring board of Comparative Example 1
Those that can be reduced by 10% are marked with ◯, and those that can be reduced by 10-30% are marked with ◎. The results are shown in Table 1, and all the examples were printed wiring boards suitable for miniaturization.

Furthermore, when a circuit is formed by the printed wiring board using the metal-clad laminates of Examples 1 to 7, the circuit is ± 10.
It was possible with an accuracy of 0 μm and was suitable for circuit formation.

The dielectric loss tangent of the substrate layer of the metal-clad laminates of Examples 1 to 7 was 0.0150 or less, which was suitable as a laminate for high frequencies.

[0032]

[Table 1]

[0033]

According to the method for producing a metal-clad laminate according to the first to third aspects of the present invention, the dielectric constant of the prepreg is in the range of 2 or more and 20 or less and the difference in the dielectric constant is 2 or more and 10 or more. By using prepregs having different dielectric constants within the range, the dielectric constant of the substrate layer of the laminated plate can be in the range of 5 or more and 9 or less depending on the designed circuit. As a result, the printed wiring board can be downsized, and a metal-clad laminate in which circuits can be easily manufactured can be obtained.

Claims (3)

[Claims] 1. A method for producing a metal-clad laminate in which a metal foil is disposed on the surface of a laminate in which a plurality of prepregs having different permittivities are stacked and heated and pressed, wherein the prepreg has a permittivity of 2 or more. A method for producing a metal-clad laminate, characterized in that the difference in permittivity is in the range of 20 or less and in the range of 2 to 10 and the permittivity of the substrate layer of the laminate is in the range of 5 to 9 inclusive. . 2. The dielectric loss tangent of the plurality of prepregs is 0.
It is 0150 or less, The manufacturing method of the metal-clad laminated board of Claim 1 characterized by the above-mentioned. 3. The method for producing a metal-clad laminate according to claim 1, wherein the laminate comprises a prepreg having a dielectric constant of 2 or more and 5 or less and a prepreg having a dielectric constant of 9 or more and 20 or less.