噴墨列印技術應用在無擋牆彩色濾光片製程之研究

Abstract

液晶顯示器已經成為平面顯示器上的重要市場，而彩色濾光片是讓液晶顯示器產生彩色畫面的一個重要的元件，目前商業界的製造方式是利用三次重複的顯影製程來製作彩色濾光片上的三個主要顏色：紅色，綠色，及藍色，但這個製造方式有些缺點，包括複雜的製程，低的材料使用率，及高的能量與化學消耗，而這些缺點可以藉由使用噴墨列印技術解決，這個技術能藉由著數位控制系統精準地控制沈積適量的材料在想要的區域，因此噴墨列印技術可以提供高效率生產來減低彩色濾光片的成本。 有著大畫素面積的彩色濾光片已經藉由在黑色矩陣上使用額外的擋牆或是使用高的梯形黑色矩陣被噴墨列印出來，因此一個新穎的製造小畫素面積彩色濾光片的方式在這篇論文中被提出，即在噴印前先在黑色矩陣玻璃基板上進行表面處理，這種方式將不需使用到擋牆或是高的黑色矩陣，而且黑色矩陣可以非常的薄，黑色矩陣的功用只是用來阻擋光線的漏光，而不是用來侷限墨水在次畫素內。一種特殊的化學處理藥劑被使用來沈積一層單層的疏水性表面在黑色矩陣玻璃基板上，噴墨在基板上的液滴將不需使用很貴的極小液滴噴頭就能縮小至適當的大小，此外，藉由加熱基板至60度C可以使墨水溢流至鄰近次畫素的現象被避免，因此這三個主要的色條將可以被輕易的完成。

Liquid crystal display has grown to be the vital market for flat panel display. Color filter is one of the key elements for making a color image. The conventional fabrication process is using three repetitions of lithography processes for three primary color films of red, green, and blue. This process has some drawbacks, including complex manufacturing process, low efficiency of material utilization, and high consumption of energy and chemicals. These drawbacks can be solved by using ink-jet printing technology. This technology can precisely control to deposit the suitable amount of materials on the desired area by the digital control system. Therefore, ink-jet printing technology can provide high efficient production to reduce color filter manufacturing cost. The color filter, which sub-pixel size is large, has been printed by using an additional rib wall on top of black matrix or a high trapezoid BM. In this thesis, a novel fabrication method for small sub-pixel size color filter was proposed by applying a surface treatment on the BM glass substrate. This method would not need the rib wall or the high BM, and the thickness of BM could be very thin. The function of BM is just to prevent the light leakage, but not to hold color inks inside the sub-pixels. A specific chemical treatment was used to deposit a monolayer of hydrophobic surface on the black matrix glass substrate. The dots ejected on the substrate would be reduced to apposite size without using tiny droplet print-head which is very expensive. Besides, the substrate was heated to 60oC to prevent the phenomenon that the color inks overflowed to neighboring sub-pixels. The three primary color strips would be achieved easily.