以全圖案模仁直接壓印退火金薄膜製作微奈米光柵之成型性分析

• Main Authors: LI, CI-TING, 李其霆
• Other Authors: AOH, JONG-NING
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/a6y7wg

碩士 === 國立中正大學 === 機械工程系研究所 === 105 === In order to fabricate composite wire grid polarizers (WPG) for polarization of liquid crystal display (LCD) we adopted the direct metal nanoimprint technique, which might replace photolithography, to fabricate metal grating in submicron scale. To allow a direct nanoimprint having good fidality, the metal grating formability is the most important factor in the direct metal nanoimprint processing. Previous results showed that the formability was better in the periphery of the grating than in the center. To deal with the non-uniform imprint result, we try to find a feasible approach to improve the process. In this study, the silicon molds with full patterned grating structure are made by E-beam lithography and dry etching with a width of 300 nm and a spacing of 600 nm and height of 200 nm. Gold thin film was used as imprint material for the grating pattern. The silicon substrates are covered with an anti-sticking layer prior to the evaporation of 300 nm-thick-gold thin film. To facilitate an easier flow and thus a better formability of the gold film during imprint, some films were annealed after evaporation deposition for comparison . The direct nanoimprint was conducted with a load of 3200 kg at 120℃. The successful experimental results reveal better formability of the annealed gold films. To analyze the formability of as-received and annealed gold films, commercial software SIMUFACT based on the finite element method was applied to simulate the metal flow process during imprint. The flow stress curves of the as-received and of the annealed Au film were obtained from the nanoindentation curves. Comparing the results between as-received Au film and annealed one, we found an interesting factor that may influence the formability. The material immediately beneath the mold teeth and adjacent to the substrate formed an area similar to a dead zone.Since annealed gold film was easier to fill the mold cavity than the as-received one, the formability during direct metal imprint was improved.