Effect of sodium thiazolinyl dithiopropane sulphonate (SH110) addition on electroplating nanotwinned copper films and their filling performance of fine-pitch redistributed layer (RDL).

Nanotwinned copper is a potential microelectronic interconnection material due to its superior strength and conductivity, however, its filling ability is urgently needed to improve before its application in the field of advanced packaging. The effect of additive (sodium thiazolinyl dithiopropane sulphonate, SH110) addition on the surface roughness, microstructure, mechanical properties and filling capacity of nanotwinned copper films was investigated. The surface roughness and grain size were firstly reduced then increased with the increasing concentrations of SH110, reaching the minimum value at 10 ppm.