Copper surface roughening agent capable of being electrolytically regenerated and recycled and preparation method thereof

Abstract

The invention relates to the technical field of metal etching, in particular to a copper surface roughening agent capable of being electrolytically regenerated and recycled and a preparation method thereof. The coarsening agent can be used for coarsening a copper surface in the manufacturing process of a PCB and an FPC and can be recycled and regenerated in an electrolysis mode to reduce wastewater discharge in an existing operation mode. Ferric iron and the copper surface are promoted to be in contact to generate a redox reaction by using ferric salt in the environment of an inorganic acid aqueous solution, part of copper atoms on the copper surface generate divalent copper ions and dispersed in the roughening agent to generate etching, an applicant finds that by adding a surfactant and the like, the diffusion rate of ferric iron to the copper surface can be increased, the dispersion of the bivalent copper ions into the solution can be promoted, and the etching amount at normal temperature within a short time can be increased; and by selecting proper accelerators, inhibitors and the like, the roughness and the uniformity degree of etching are favorably regulated and controlled, and the adhesion force and the adhesion stability of the copper surface are favorably improved.

Description

Technical field[0001]The present invention relates to the technical field of metal etching. More specifically, the present invention relates to a copper surface roughening agent that can be recycled by electrolytic regeneration and a preparation method thereof.Background technique[0002]Printed circuit boards, such as PCB and FPC, are the basic components of various consumer electronic products and investment electronic products, and are also an important part of modern electronic construction technology. Stimulated by the rapid development of the information industry, the production scale of printed circuits has become larger and larger. As the main product of electronic systems, it has been widely used in all electronic products. Copper surface pretreatment in PCB and FPC processes. Copper surface roughening is an important step in copper surface treatment. On the one hand, roughening requires effective removal of impurities, oxides and other residues from the copper surface (inclu...

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Problems solved by technology

[0003] At present, sulfuric acid-hydrogen peroxide, persulfide and other systems are generally used for copper roughening, but peroxides have the problem of large heat release, while iron-based etching solutions have the advantages of simple formula and low price, and etch through metal redox , has high copper melting ability and low cost, but has the disadvantages of slow etching speed and low etching ability, which makes the roughness and copper surface etching uniformity low, and low roughness will cause copper surface adhesion Decline, and uneven etching will affect the adhesion stability of the copper surface and the substrate, and when using an iron-based roughening agent for etching, it generally needs to be around 40°C, and the etch rate stability is poor

[0004] And in the process of etching roughening, Fe3+ in the roughening agent gradually turns into Fe2+ and loses the etching ability. At the same time, the total iron content increases, and the output of ferric chloride etching waste liquid is large. Heavy metals such as Cr, Ni, Cu, Mo, Mn, Zn, Al also enter the waste liquid, and the discharge is not up to standard, and a large amount of iron as waste also causes waste of resources, so it is necessary to provide a recycling recycling roughening agent

[0005] In addition, the patent CN105887088A provides a new type of ferric chloride etching solution. By using ferric chloride, hydrogen chloride, sodium chloride and water as the etching system, it has a high etching rate, and the etching amount per minute at 48 ° C can be It reaches 12.5 microns, but the etchant provided by this patent still promotes etching through high temperature, and as the etching amount increases, the roughness of the copper surface gradually increases, and the attenuation of high-frequency signals will become more and more obvious, which cannot meet the fine processing requirements

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