Versatile Micro and Nano Patterning Technique for TiO₂ and TiN‐Based Sol–Gel Thin Films

Abstract This paper describes a tailored and versatile technology route to achieve micro and nanopatterning of both TiO₂ and TiN thin films using a direct photo patternable sol–gel approach combined with a rapid thermal annealing and nitridation process. The approach consists in multi‐scale structuring TiO₂ using laser direct writing or mask/colloidal lithography on a wide range of substrates including materials and of diverse geometry. These patterned TiO₂ layers can subsequently be converted into a micro‐structured metallic TiN layer using a direct rapid thermal nitridation process that results in metallic thin films (TiN). This work demonstrates the versatility of this complete chain of soft chemistry based new process for patterning TiO₂ and TiN thin films thereby avoiding expensive processes such as etching and lift‐off, while preserving their diffractive properties and high thermal stability, that is, up to 1000 °C under vacuum. The process is compatible with different kinds of substrates of different shapes and sizes. These results pave the way for developing a cost‐effective and time‐saving approach to different cutting‐edge applications such as metasurfaces, sensors, and applications in the luxury and decoration sector.