氣溶膠噴塗印刷技術改善液晶元件特性之研究

Abstract

本論文研究利用氣溶膠噴塗印刷技術製作以及改善液晶元件，將導電性銀墨水霧化成氣溶膠，藉由氣流調控使其銀墨水聚焦並沉積於基板，製作散狀、點狀以及線狀陣列三種奈米銀結構。將使用三種奈米銀結構的運用改善膽固醇液晶之臨界電壓以及轉態時間，在沒有反射率喪失的情況下，可以降低7%~27 %的臨界電壓以及加快5.6倍的轉態時間，結果顯示缺陷點的高度為影響膽固醇液晶光電特性的主要因素。另外使用氣溶膠噴塗印刷Vertical Alignment Fringe-Field Switching (VA-FFS)中的線狀陣列電極，不僅提升製作液晶元件效率，且利用噴塗不同銀電極之高度，使電場更深入液晶盒中，有效降低飽和電壓23 %以及加快元件反應時間。

In this research, we investigated the ability of Aerosol Jet Printing (AJP) technique to fabricate and improve in liquid crystal display devices. The three kinds of surface nano-silver structure, which are dot、spray and line array, could be defined with the proper carrier gas and sheath air flowrate. With the combination of these three kinds of nano-silver structure, the E-O properties of cholesteric liquid crystal can be enhanced and the reflectance can still reach the limit. The threshold voltage can be reduced by 7%~27% and the transition time is 5.6 times faster. The results of this study confirm the height of nano structure is the dominating parameter instead of the density and distribution of nano structure. Besides, the electrodes of Vertical Alignment Fringe-Field Switching (VA-FFS) line array are fabricated by Aerosol Jet Printing. Enhance not only the fabrication efficiency, but also the height of nano-silver structure which makes the electric field penetrates deeper into the cell. In the case of 700 nm electrode pattern, the saturation voltage can be reduced by 23% and the transition time can be accelerated.