Electroless copper plating of dielectrics from environmentally friendly reducer-free electrolyte

Abstract

ABSTRACT In recent years, the specificity of the demand for selective, adaptable and inexpensive methods has always been one of the key factors in support of further research on electroless copper plating. In essence, this is a rather complex process involving several pretreatment steps. The electrolytes used are potentially unstable due to the spontaneous onset of nucleation as a result of local changes in pH or ongoing reactions between the products and the metal ions, which form insoluble salts. The aim of the present investigation has been to study the possibilities for obtaining thin copper coatings from an environmentally friendly electrolyte for electroless copper plating, which does not contain a toxic reducing agent. A comparison was made between copper layers on acrylonitrile-butadiene-styrene (ABS) polymer obtained by two different deposition techniques: the first used an environmentally friendly electrolyte for chemical copper plating without reducer, and the second – a trilonic copper electrolyte containing formaldehyde as a reducer. The following methods were used to study the morphology, structure and elemental composition of the obtained layers: scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and energy dispersion X-ray analysis (EDS).