The effect of low-energy ion bombardment on the microstructure of copper films will be described. The copper films have been deposited on SiNx-coated, oxidized Si wafers by magnetron sputtering with a simultaneous bombardment of low-energy argon ions (60 eV). The films were annealed at 450°C in HV. The ion bombardment leads to a stronger and sharper {111} texture of the as-deposited films. After annealing, the ion-bombarded films had a significantly smaller grain size than films produced without ion bombardment. The experimental results will be discussed relating the textures of the as-deposited films with the grain sizes obtained after annealing. Details will be given describing how the microstructure of Cu films can be tailored using low-energy argon ion bombardment.

Despite much research focused on lithium (Li) metal batteries, an important issue concerning Li-dendrite growth on the anode remains unresolved. The intrinsic mechanism of this Li-dendrite formation is related to the non-uniform distribution of Li-ion flux on the anode in charge/discharge caused by irregular structure and energy of anode surface. Here we report upon dendrite-free Li-deposition in a carbonate-based electrolyte using a novel Cu anode structure with sharp wrinkles and a [100] crystal facet. This uniform Li-deposition resulted in long-term electrochemical cyclability in Li/Cu and LiFePO4/Li cell. Our observations revealed that the wrinkled Cu surface and the unifying [100] crystal facet play important roles in enhancing the uniformity of the Li-ion flux and the adsorption energy of the Li-ions on Cu, respectively. We expect that this study will permit the use of a wide range of wrinkled structures and crystal planes to obtain high-energy and long-term cycles of Li-metal batteries.