Direct patterning of metal oxides by hard templates and atomic layer deposition

Abstract

We describe a procedure for one-step patterning of thin films of metal oxides (TiO2, Al2O3, and ZnO) using reusable hard templates and atomic layer deposition (ALD). This procedure, called contact area lithography (CAL), was inspired from an idea of pattern transfer at a contact area, which realises high patterning fidelity, and enables a universal approach for the nano/micrometre scale patterning of both inorganic and organic thin films, such as self-assembled monolayers [1]. Patterned hard silicon oxide was employed as a hard template and water-induced bridge formation is attributed to the origin of the observed adhesive contact force between the substrates and the templates during the pattern transfer. Non-contacted areas were served as growth sites for thin layers of various metal oxides by using ALD. CAL is a simple and universal method to form hard oxide thin film patterns without incorporation of resistive layers, and should have potential for applications in micro/nano electronics, optoelectronics, flexible electronics, biochips, and complex nanostructure fabrication.