Kinetic and Microstructural Control of Elemental and Composite Electrodeposited Metallic Thin Films

Electrodeposition plays a key role in current industry by providing metallic coatings and nanoscale materials for electronic, optical, magnetic, wear, corrosion, and even aesthetic applications. Current manufacturing processes rely heavily on chemical additives, whose effects are poorly understood, in order to optimize the microstructure and properties of these materials. A novel alternative approach using under potential deposited (UPD) monolayers of a mediating metal to produce high quality metallic materials with low intrinsic stresses and resistivities without the use of complex additives is presented here. Specific attention is given to the deposition of Ag and Cu using Pb as the mediator metal. These materials display up to 85% reductions in intrinsic stress and improved crystal quality compared to samples synthesized in the conventional manner. Applications of this approach for thin film and nanostructured materials processing will be discussed. Electrochemical deposition of uniformly dispersed and hierarchical composite structures will also be discussed. This technique presents a means of substantially improving the mechanical properties of electroplated material. Specific attention is given to a model Ni matrix - Al2O3 nanoparticle composite system. Manufacturing capabilities, scalability, and unique mechanical properties of this system are presented. These mediated and composite deposition techniques are significant advancements in electroplating technology and allow for tuning of microstructures and material properties