JPS59109350A - Laminated board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a laminate used for IC circuits and the like.

Conventionally, printed wiring boards (PWB) include paper phenol laminates, a-epoxy laminates, glass epoxy laminates, glass polyimide laminates, and other laminates with metal foils such as copper foil adhered to them; A ceramic substrate with metal foil such as copper foil attached is used. However, by using the above-mentioned laminated board, it is difficult to increase the density of the printed wiring board, increase the number of layers (multilayer wiring), or increase the calculation speed.

On the other hand, if a ceramic substrate is used, the size of the printed wiring board is limited because it is difficult to manufacture a large-sized one and the ceramic substrate is easily broken. Moreover, there is a problem in that the above-mentioned laminates and ceramic substrates are relatively heavy.

The inventors focused on laminates that do not have the problem of limited size, and aimed to increase the density of printed wiring boards by lowering the coefficient of thermal expansion of laminates and improving their dimensional stability, especially under heat. By reducing the dielectric constant of the laminate, it was possible to increase the calculation speed, and further research was conducted to reduce the weight of the laminate. As a result, they discovered that these problems could be solved all at once by including aromatic polyamide fibers in the base material, and the present invention was hereby completed.

That is, the present invention provides a laminate formed by laminating and molding a predetermined number of resin-impregnated base materials, wherein at least one of the resin-impregnated base materials is made by twisting aromatic polyamide fiber threads and glass fiber threads. The gist is a laminate that is characterized by being a composite yarn cloth woven using composite yarns. The present invention will be described in detail below.

A laminate is made by laminating and molding a predetermined number of resin-impregnated base materials (prepregs), and in the laminate according to the present invention, at least one of the resin-impregnated base materials is an aromatic boron. It differs from conventional products in that it is a composite yarn cloth (composite cloth) woven using a composite yarn made by twisting noamide fiber yarn and glass fiber yarn. Since the above-mentioned composite yarn fabric is used, the coefficient of thermal expansion of the laminate is lowered, the dimensional stability in particular under heat is improved, and the dielectric constant is also lowered. Moreover, it is also lightweight.

DuPont's Kevlar is famous as an aromatic polyamide fiber. The type of glass fiber yarn is not particularly limited. For example, E-glass (Owen-s-Cornin
g (manufactured by Fiber Glass), etc. are used.

As the resin to be impregnated into the composite yarn cloth, the same resins as those commonly used in the past are used, and polyimide resins, epoxy resins, and polybutadiene resins are preferably used.

When a resin-impregnated base material is made by impregnating a composite yarn cloth in which Kevlar is used as an aromatic polyamide fiber with polyimide resin (Kelimide 601), and a laminate is made by laminating and molding this, the coefficient of thermal expansion is 10'. xx/in
It is as low as 'C, and the dielectric constant is approximately 4 x 106
11zJ), lower and lower results are obtained.

When a resin-impregnated base material of a type other than the composite yarn fabric impregnated with a resin is used, the type is not particularly limited. For example, glass cloth impregnated with epoxy resin or polyimide resin, quartz cloth impregnated with polyimide resin, etc. are used. ``The type of resin-impregnated base material used, the number of the base materials, and the position of overlapping must be appropriately determined depending on the intended use of the laminate.

Note that it is desirable that the composite yarn fabric be processed in a dehumidified state. In addition, if a plasma-treated composite yarn fabric is used, the water absorption rate of the laminate will be reduced, resulting in better electrical insulation and better adhesion (interlayer adhesion) during laminated molding. Become.

For example, polyimide resin (Kelimide 601
) to create a resin-impregnated base material and then layer-molding it to make a laminate. If the composite yarn fabric is plasma treated, the water absorption rate will be around 2% ( 0.4t), which is about half, and the adhesive strength is 1.2kg/c.
rh increases twice as much. Here, plasma treatment refers to plasma (an electrically neutral ionizable gas) generated by applying high frequency power to an inorganic gas or an organic gas in a vacuum of 0.01 to 1.0 Torr, for example. , excited molecules, ions, and electrons) on the substrate to modify its surface properties or form a polymeric film. Processing is usually carried out by placing the substrate in a vacuum chamber with an anode and a cathode arranged in a predetermined manner. In order to improve workability, it is preferable to continuously introduce and extract the base material into the vacuum chamber.

If necessary, when manufacturing a metal foil-clad laminate in which a metal foil such as copper foil is attached to one or both sides of the laminate, a resin-impregnated base material may be laminated on one or both sides of the laminate. Either the metal foils are combined and then molded, or the laminate is made and then the metal foil is attached to one or both sides of the laminate.

The laminate according to the present invention is constructed as described above, and since at least one of the resin-impregnated base materials is made of the composite yarn cloth as described above, the coefficient of thermal expansion is low. It has excellent dimensional stability, especially when heated. Therefore, it becomes possible to easily increase the density and multilayer of printed wiring boards. The printed wiring board equipped with this laminate is used as a leadless IC chip (ceramic type, plastic type, etc.) carrier.
It is very suitable for reading and listening. Furthermore, since the dielectric constant is low, calculation speed can be easily increased.

Moreover, it is lightweight.

Next, Examples and Comparative Examples will be described.

〔Example〕

In the following manner, a laminated board of an example having copper foil adhered to both sides was produced.

As the composite yarn cloth that becomes the base material, the composite yarn is plain woven and the thickness is 0.
．． Dancing 18m, the arrangement of curly threads was 42/25 cranes.

A material with a weft arrangement of 32/25 xra was used. However, the composite yarn is made by twisting an aromatic polyamide fiber yarn and a glass fiber yarn so that the MW ratio is 1:1. A resin-impregnated base material was prepared by impregnating the composite yarn cloth as described above with polyimide so that the amount of resin was 50% by weight.

After stacking six of these resin-impregnated base materials and adding 35 μm thick copper foil to the top and bottom surfaces, 165"C, 70kg
Laminate molding was performed by heating and pressurizing for 90 minutes under the conditions of /- to obtain a laminate.

A comparative laminate with copper foil attached on both sides was made with a thickness of 0.1
It was made in the same manner as in the example except that 8 m of glass cloth was used as the base material.

The thermal expansion coefficient and dielectric constant of the laminates of Examples and Comparative Examples were measured. The measurement results are shown in Table 1.

Table 1 From Table 1, it can be seen that the laminates of the examples have lower coefficients of thermal expansion and dielectric constants than those of the comparative examples.

Agent: Patent Attorney Takehiko Matsumoto

Claims (1)

[Scope of Claims] (11) A laminate formed by laminating and molding a predetermined number of resin-impregnated base materials, wherein at least one of the resin-impregnated base materials includes an aromatic polyamide fiber thread and a glass fiber thread. (2) The laminate according to claim 1, wherein the composite yarn cloth is plasma-treated. Board.