Microscopic Studies of Alignment Layers Processed by a Focused Ion Beam for the Creation of Liquid Crystal Metasurfaces

The focused ion beam treatment of substrates with transparent electrodes coated with rubbed polymer layers is a key step in creating liquid crystal metasurfaces. This treatment provides local control over the liquid crystal alignment near the substrate surface. The structure, composition, and optical properties of the FIB-treated substrate surface were studied by the scanning electron microscopy, transmission electron microscopy (TEM), atomic force microscopy, optical microscopy, and Auger electron spectroscopy. The effects of rubbing and ion-beam irradiation are analyzed to elucidate the microscopic features and the reasons for changes in aligning properties.