Resin board to be subjected to ozone treatment, wiring board, and method of manufacturing the wiring board

Abstract

A resin board that consists of at least one of a mixture of a plurality of types of resins having different degrees of susceptibility to erosion by an ozone solution, and a resin having, in a molecule, a plurality of types of components having different degrees of susceptibility to erosion by the ozone solution is treated with ozone water to form a reformed layer, and a catalyst metal is adsorbed by the reformed layer so as to form a resin-metal composite layer, on which a plating process is performed. In the resin board, a component or components that is / are likely to be eroded on by the ozone solution dissolves into the ozone solution, and pores or clearances on the order of nanometers are formed between the component(s) and a component or components that is / are less likely to be eroded by the ozone solution. With the plating deposited in the pores or clearances, the adhesion strength is improved due to an anchoring effect. Thus, the adhesion strength of the plating film is improved even where the resin-metal composite layer has a thickness of 10 to 200 nm.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]This invention relates to resin boards for use in wiring boards, wiring boards formed from the resin boards, and a method of manufacturing the wiring boards.[0003]2. Description of the Related Art[0004]Resin is finding remarkably increased use in the fields where metal is conventionally used, owing to its features, such as the ease with which resin can be shaped, a high degree of flexibility in characteristic values, such as strength, and lightness in weight. However, resin also has drawbacks, such as the absence of electrical conductivity and low hardness, and therefore, it has been proposed to combine resin with metal, or the like, so as to eliminate these drawbacks.[0005]As an example of method for providing resin with electrical conductivity, powder of a conductive metal or carbon fibers, for example, is mixed into the resin. However, a large amount of conductive metal needs to be added to the resin so as to impart ...

AI Technical Summary

Benefits of technology

[0032]In addition to the above-indicated components, other thermosetting resin(s) or thermoplastic resin(s), and additives, may be used as needed in the resin board of the invention, provided that they are not detrimental to the effect of the invention. The thermosetting resin(s) may be selected from, for example, a monofunctional epoxy resin serving as a diluent, alicyclic multifunctional epoxy resin, rubber modified epoxy resin, an acid anhydride compound serving as a curing agent for epoxy resin, block isocyanate resin, xylene resin, and a polymerizing resin serving as a radical generating agent. The thermoplastic resin(s) may be selected from, for example, polyimide resin, polyamide imide resin, polyether imide resin, polysulfone resin, polyether sulfone resin, polyphenylene ether resin, polycarbonate resin, polyether ether ketone resin, and polyether resin. Examples of the additives include organic fillers, such as silicon powder, nylon powder, and fluorine powder, thickening agents, such as orben and bentone, silicone base, fluorine base, and high polymer base antifoaming agents or leveling agents, imidazole base, thiazole base, triazole base compounds, and an agent, such as a silane coupling agent, for improving the adhesiveness.

Problems solved by technology

However, resin also has drawbacks, such as the absence of electrical conductivity and low hardness, and therefore, it has been proposed to combine resin with metal, or the like, so as to eliminate these drawbacks.

However, a large amount of conductive metal needs to be added to the resin so as to impart sufficiently high conductivity to the resin, which may cause adverse influences on the physical properties and increased cost.

The physical method generally requires large-sized equipment, such as a vacuum tank, and thus suffers from significant restrictions in terms of space or productivity, which undesirably results in increased cost.

In the case where a film of metal is formed on a resin surface by electroless plating, the strength of adhesion between the metal film and the resin is low, and the metal film is likely to peel off from the resin.

However, the method that makes the resin surface rough by etching causes a reduction of the surface smoothness, and requires the use of a poisonous or deleterious substance, such as chromic acid, permanganic acid, or sulfuric acid, giving rise to a problem concerned with treatment of waste liquid.

In the meantime, the technology disclosed in JP-A-2005-042029 has a problem that the adhesion strength of the plating film is low if the thickness of the resin-metal composite layer is small, more specifically, is about 20-200 nm.

Thus, if a resin-metal composite layer having a thickness greater than 200 nm is formed, it is difficult to completely remove the plating film and resin-metal composite layer between wires even with etching, causing a problem of insufficient or faulty insulation.

Images