The Fabrication Of Copper Nanostructured Materials In Ultrathin Layer By Electrodeposition

With their new properties and the applications in so many fields,nano materials and nanostructured materials have become the focus of basic investigation since 1990.Recently, the fabrication of ordered nanostructued arrays is the focus of the research of nano/microstructures. The electrodeposition has been used to produce materials with nano/microstructures that can not be fabricated by traditional techniques, from well-ordered structures to comprising quite unexpected forms.The electrodeposition without imposed templates becomes a new investigation field.Now this method is more and more applied in so many domains, such as microelectronics, optoelectronics and biochemistry, so people pay more attention on it.In this paper, a quasi-two-dimension ultrathin layer is built up with the assistance of icing up. In this layer, several new patterns of copper on silicon substrate with a measured periodic potential are deposited. Figure, structure and component results are tested by optical microscope, XRD, SEM and TEM. A bundle of Cu wire is connected in a circuit, so an I-V curve is measured from the circuit which shows the resistance of the wire. Here are the conclusions:The deposit of circularity-like structure is consisted of Cu and Cu2O, the content of Cu is much higher than Cu2O's. On the one hand, the periodic voltage results in the periodic structure; on the other hand, the changing voltage leads to the diversification of the balance between the migratory positive ions and the ones that the growth front expended. This is the reason why the ridges and the slopes occur. The center of the circularity-like structure becomes a point-like cathode so that the deposits can grow around the center.The bamboo-like deposit is consisted of Cu and Cu2O, too. The content of Cu is much higher than Cu2O's. These deposits also has periodic structure just like the circularity-like structure, the reason is the same as the circularity-like structure's. The changes of voltage and the thickness of the ultrathin layer lead to the branching off.The ladder-like deposit is consisted of only Cu. At an especial condition, when a constant current was applied to the electrodes, the electric field distribution along the growth direction has a sinusoidal-like variation and leads to the periodic structure. So in the middle and the fours borders, the probabilityν* that a nucleus catches the ions from the fluid are diverse. This reason results in the ladder-like structure.The I-V curve shows that the sample is conductor and the resistance is about 12-14 KΩ.The experiment results and the theoretic analysis will be useful for the investigation of fabricating nano/microstuctured materials with the electrodeposion method.