Fabrication of Al₂O₃ nano-micro patterns by Al₂O₃ dispersion resin using UV imprint lithography

Aluminum oxide (Al₂O₃) has excellent properties in terms of hardness, abrasion resistance, refractive index, electrical insulation and chemical stability; therefore, it has been used in various optical applications such as for resistance random access memory active layers and nano-micro polishing. In this study, a functional Al₂O₃ nanoparticle resin with refractive index control was developed and various nano-micro structures were formed using UV-nanoimprint lithography. It is also possible to adjust and measure the desired optical properties by controlling the specifications of the formed Al₂O₃ structures. It was confirmed that imprinting is possible not only on traditional rigid substrates but also on flexible ones. Furthermore, scanning electron microscopy showed that the various Al₂O₃ nano-micro structures were well formed. The effect of annealing temperature on the phase change and crystallinity was investigated by X-ray diffraction. The hardness and Young's modulus were also measured by using a nanoindenter. The refractive index of Al₂O₃ dispersion resin composition was examined using an ellipsometer. Moreover, the optical characteristics of each Al₂O₃ nano-micro structure were measured by UV–visible spectroscopy.