Effect of Sulfuric Acid Copper Plating Electrolyte Operation Duration on the Structure and Thermomechanical Stability of Through Holes Small Diameter Copper Coatings

The copper sulfate electrolyte operation duration effect on the structure and stability of through holes electroplated copper coatings thermal shock is studied. Electrodeposition in a high-frequency reverse mode with rectangular current pulses in the presence of a complex additive makes it possible to ensure uniform distribution of copper in through holes. At the beginning of the copper coatings electrolyte operation a flat crystallization texture with a predominance of atomic planes [220] is observed, it characterized by X-ray diffractometry. As the electrolyte is used, the crystallographic orientation [111] of the electrodeposited copper appears and becomes predominant, resulting in an increase in the surface roughness of the coatings. Since the copper content in the electrolyte remained virtually unchanged during electrolysis according to X-ray fluorescence spectroscopy, the observed texture changes may be related to the consumption of the inhibitory additive gloss-forming component. This assumption is confirmed by cyclic voltammetry. As the concentration of the gloss-forming component decreases during operation, the through holes copper coatings thermal shock resistance decreases.

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