Nano-scale patterning process using selective wetting and its applications

Abstract

Nano-scale patterning is a key enabler of nanotechnology and has played a pivotal role in enhancing performance capabilities and in the realization of new functionalities in a wide range of applications, including electronics,optics, energetics, and even biology. While cutting-edge lithographic processes based on deep UV or electron beam methods have successfully led the evolution of modern nano-patterning technologies, their use has been limited to a few high-end applications due to the very high costs associated with the equipment and the multi-step processes required. In this respect, alternative nano-patterning methods have been proposed, such as simplified lithography techniques, nano-transfer methods, and the capillary assembly method. However, significant advances are still required to realize a cost-effective and scalable nano-patterning process with a high degree of freedom, a wide range of applicability, and a practicable throughput. Here, we propose a direct, additive, and solution-based nano-patterning route by employing selective wetting on engraved hydrophilic nano-patterns with a hydrophobic top surface prepared by a one-step imprinting process. The proposed process produces uniform single- or multilayer nano-patterns over large area at high speeds and exhibits good compatibility with a wide range of substrates,including plastics, paper, or even banknotes. Experimental results are supported by an analysis based on a fluid-dynamic simulation which sheds light on the operation mechanism and key controlling parameters of the proposed process.