Electrodeposition of stress-relaxation-induced (111)-oriented nanotwin copper film by direct current in additive-free electrolyte

Abstract

In this study, we investigated the electrodeposition of stress-induced (111)-oriented nanotwin copper films using direct current in an additive-free electrolyte. We aimed to explore the effects of temperature, current density, and agitation on the formation of nanotwins. At lower temperatures, (111) orientation was induced due to the decrease in adatom surface diffusion. Additionally, higher current densities, which induced high initial residual stress, promoted the formation of (111)-oriented nanotwins, resulting in stress relaxation and a reduction in residual stress. Agitation had a negligible effect on nanotwin formation in our experiments, which were conducted in the additive-free electrolyte. Our findings provide valuable insights into the controlled formation of (111)-oriented nanotwin Cu films and their potential applications in fields requiring Cu films with superior mechanical and electrical properties, which are improved by the formation of nanotwins. By comprehending the fundamental mechanisms involved, it becomes possible to optimize electrodeposition processes for (111)-oriented nanotwin copper films.