Versatile Zirconium Oxide (ZrO2) Sol-Gel Development for the Micro-Structuring of Various Substrates (Nature and Shape) by Optical and Nano-Imprint Lithography

Abstract

Zirconium oxide (ZrO2) is a well-studied and promising material due to its remarkable chemical and physical properties. It is used, for example, in coatings for corrosion protection layer, wear and oxidation, in optical applications (mirror, filters), for decorative components, for anti-counterfeiting solutions and for medical applications. ZrO2 can be obtained as a thin film using different deposition methods such as physical vapor deposition (PVD) or chemical vapor deposition (CVD). These techniques are mastered but they do not allow easy micro-nanostructuring of these coatings due to the intrinsic properties (high melting point, mechanical and chemical resistance). An alternative approach described in this paper is the sol-gel method, which allows direct micro-nanostructuring of the ZrO2 layers without physical or chemical etching processes, using optical or nano-imprint lithography. In this paper, the authors present a complete and suitable ZrO2 sol-gel method allowing to achieve complex micro-nanostructures by optical or nano-imprint lithography on substrates of different nature and shape (especially non-planar and foil-based substrates). The synthesis of the ZrO2 sol-gel is presented as well as the micro-nanostructuring process by masking, colloidal lithography and nano-imprint lithography on glass and plastic substrates as well as on plane and curved substrates.

Innovative Process to Obtain Thin Films and Micro-Nanostructured Zrn Films from a Photo-Structurable Zro2 Sol-Gel Using Rapid Thermal Nitridation

“…The process used to produce the sol-gel was previously published [27]. Briefly, the ZrO 2 sol-gel was prepared from a mixture of two sols at room temperature.…”

“…E-beam lithography and dry etching [25] or scanning probe microscopy oxidation and hydrofluoric acid etching [26] were used for this purpose, but these techniques are time consuming, use toxic products, and are expensive. Conversely, sol-gel ZrO 2 can be easily structured by UV exposure [27], thereby making it possible to create ZrN micro-nanostructured thin films with complex shapes after nitridation.…”

Micro-nanostructuring of ZrO2 sol-gel by optical and nanoimprint lithography on various substrate for optical applications

“…These techniques are commonly used in thin film deposition but do not easily permit micro-and nano-structuring to create complex patterns without an additional etching step, limiting their applicability and properties. Another option for producing ZrO2 thin films is the sol-gel method [26][27][28][29][30][31] . The sol-gel method allows the micro-nanostructuring of thin films through techniques such as optical 29,[31][32][33][34] and nanoimprint lithography [35][36][37] .…”