Chemical-copper solution and chemical copper plating method

Abstract

The invention relates to the technical field of nonmetallic surface chemical plating treatment, in particular to a chemical-copper solution. The chemical-copper solution comprises a pre-plating copper solution and a thick copper plating solution. The pre-plating copper solution comprises copper salt, formaldehyde, a first complexing agent, a stabilizing agent, a surface active agent, an accelerant and a pH adjusting agent. The thick copper plating solution comprises copper salt, formaldehyde, a second complexing agent, a stabilizing agent, a surface active agent, an accelerant and a pH adjusting agent. The first complexing agent is a mixture of ethylene diamine tetraacetic acid and tetrahydroxypropyl ethylenediamine. The second complexing agent is a mixture of tartrate and triethanolamine. The chemical-copper solution is stable in performance, convenient to maintain, safe and environmentally friendly; the pre-plating copper solution is high in activity and the thick copper plating solution is good in stability, the pre-plating copper solution and the thick copper plating solution are applied to different stages of the chemical copper plating method respectively, the chemical plating work efficiency is high, obtained plating layers are combined reliably, the yield of copper plating pieces is high, and large-scale industrial production is facilitated.

Description

technical field [0001] The invention relates to the technical field of non-metal surface electroless plating treatment, in particular to an electroless copper plating solution and a method for electroless copper plating on non-metal surfaces. Background technique [0002] Electroless plating is a metal deposition process in which metal ions are reduced under the self-catalysis of the metal surface by an appropriate reducing agent in the solution. Electroless plating can only be performed on a catalytically active surface. The traditional non-metallic surface activation method uses colloidal palladium, but the colloidal stability is poor, and palladium is expensive, resulting in high activation costs. As a result, low-palladium and palladium-free processes gradually emerged; a common palladium-free activation process is to directly dope metal-organic compounds in non-metallic substrates, and use laser ablation to destroy the valence bonds in it to obtain catalytic metals. Pa...

AI Technical Summary

Problems solved by technology

Most commercial electroless copper plating solutions use formaldehyde as a reducing agent. There are two basic chemical reactions in the reaction process, that is, copper ions obtain electrons and become copper simple substances, and formaldehyde reacts with hydroxide ions to produce hydrogen, water and carboxylate ions and give electrons; in addition to the effective oxidation-reduction reaction of copper ions on the catalytic surface, which is reduced to metal copper by formaldehyde, there are many side reactions, mainly including the Canelocha reaction and non-catalytic reactions. In the above-mentioned non-catalytic reactions In the process, the particles of cuprous oxide are reduced, and thereafter, cuprous oxide may be further reduced into particulate copper. The above-mentioned side reactions not only consume the active ingredients in the particles, but also produce cuprous oxide, copper and very fine particles. The powder is suspended in the plating solution, it is difficult to get out by filtration, and it is easy to cause the decomposition of the plating solution. If cuprous oxide and copper are co-deposited, the copper deposition layer will be loose and rough on the surface of the piece to be plated, and the copper deposition layer will be made, that is, The bonding force between the copper plating layer and the substrate to be plated is poor, and the increase of copper powder will cause further damage to the copper plating solution

[0004] Conventional electroless copper plating solution forms poor stability of copper plating layer on non-metallic surface after palladium activation, and cannot thicken copper plating, and if simply increase the amount of stabilizer in electroless copper plating solution, it will easily affect the Generally speaking, the higher the plating speed, the harder it is to control the stability, and the better the stability, the harder it is to increase the plating speed