Improving ultrasonic embossing process of copper nanowire

Abstract

One-dimensional metallic nanostructures have been of great interest as their properties could be customized for specific applications through a variety of nanoimprinting methods. As most metallic nanowire arrays fabrication methods are limited by long fabrication time and high costs, ultrasonic nanoimprinting has been identified as one of the preferred methodologies with its one-step operating cycle. Despite being a novel method, ultrasonic nanoimprinting offers a variety of advantages, with its key advantages being simplicity and cost-effectiveness. This technology involves the use of a template to extrude nanowires using high-frequency mechanical vibrations. Nonetheless, this method has been challenged with issues relating to the high viscosity and annealing temperatures of the metals. Thus, this project aims to further explore the potential of ultrasonic nanoimprinting with the use of lubrication and eat to fabricate longer and denser nanowire arrays. Lubrication involves the incorporation of a procedure to treat the Anodised Aluminium Oxide (AAO) template with nano-lubricant containing C60 fullerene nanoparticles, with the use of a vacuum prior to the embossing process. Moreover, with the added usage of a thermostatic heater during the embossing process, copper nanowires of up to 10μm were successfully formed. The successful fabrication of longer and denser nanowire arrays was found to be highly dependent on the temperature of metal substrates.