Ultrafast laser induced nanostructured ITO for liquid crystal alignment and higher transparency electrodes

• Main Authors: Solodar, A., Cerkauskaite, A., Drevinskas, R., Kazansky, P. G., Abdulhalim, Ibrahim
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2019
• Subjects: Liquid Crystal Alignment; Ultrafast Laser; DRNTU::Engineering::Materials
• Online Access: https://hdl.handle.net/10356/88512; http://hdl.handle.net/10220/47612
• Institution: Nanyang Technological University

Femtosecond laser nanostructured indium tin oxide (ITO) coated glass is shown to act both as a liquid crystal (LC) alignment layer and as an electrode with higher transparency. The nanopatterns of the 120 nm period were created using ultrashort laser pulses directly on ITO films without any additional spin coating materials or lithography process. Nine regions of laser-induced nanostructures were fabricated with different alignment orientations and various pulse energy levels on top of the ITO confirming the follow-up of the LC director to the line orientation. The device interfacial anchoring energy was found to be ∼1μ J/m2, comparable to the anchoring energy of nematic LC on photosensitive polymers. The transparency as an electrode was found to improve due to the better antireflection and lower absorption expected from a nanostructured surface.