Improvement in the optical and electrical properties of Ga-doped zinc-oxide films by using nano-imprinted pattern arrays and post-annealing

Design and Fabrication of Information Security Films with Microlouver Pattern and ZnO Nano-Ink Filling

“…The microlouver films used in experiments were fabricated in the following sequence through the silicon stamp mold and nanoimprint process. 5,6) A UV-curable resin (ND-938-6, refractive index n = 1.48, NP Chemical, Korea) was applied to a polyethylene terephthalate (PET) film, which was then compressed with a pre-fabricated isosceles trapezoidal silicon mold. A microlouver-patterned film was fabricated by curing the resin with 120 W UV irradiation and removing the mold.…”

“…A microlouver-patterned film was fabricated by curing the resin with 120 W UV irradiation and removing the mold. [6][7][8] Four oxides with high refractive indices, i.e., ZnO (n = 2.00), ZrO 2 (n = 2.15), TiO 2 (n = 2.34), and CuO (n = 2.63), were selected as shadowing materials for microlouver filling. The nano-inks (Dittotechnology Co., Korea) had concentrations of 20 wt% and were composed of 10 -20 nm nanoparticles.…”

“…This study aims to develop a few-step process for fabricating high-quality information security films filled with shadowing materials suitable for microlouver patterns using nanoimprinting and nano-inking. 5,6) The following research process was conducted to fabricate microlouver films with excellent security characteristics through a controlled viewing angle. First, film security characteristics were investigated according to shadowing material type for filling an isosceles trapezoidal pattern using an optical simulation method, and the results were verified through experiments.…”