應用反應曲面法改善液晶顯示器之彩色濾光片製程能力問題

Abstract

薄膜電晶體液晶平面顯示器（Thin Film Transistor Liquid Crystal Display，TFT-LCD）的彩色化毫無疑問是一定的趨勢，因而含有紅色、綠色、藍色三原色的彩色濾光片，乃成為重要且必備的周邊材料，由於一片液晶顯示面板是由一片相等大小的彩色濾光片（Color Filter，CF）配對一片薄膜電晶體陣列（TFT Array） 所製造而成，因此彩色濾光片品質的好壞對液晶顯示面板的色彩表現有決定性的影響。 在 TFT- LCD 面板組裝過程中，需藉由間隙子（Spacer）均勻地分佈在基板上，以作為薄膜電晶體（TFT）與彩色濾光片（CF）間之支撐，並維持薄膜電晶體與彩色濾光片間的間隙以灌注液晶。光阻柱狀物（Photo Spacer，PS）是採用感光性樹脂材料，利用已經非常成熟的微影製程（Photolithography）製作間隙子，將間隙子製作在黑色矩陣（Black Matrix，BM）上，如此可精確的控制間隙子大小及所在位置，防止間隙子移動，使液晶包間隙（Cell Gap）維持良好的均勻度，同時可避免間隙子周圍漏光以提高對比。 本研究即針對彩色濾光片中之光阻柱狀物製程問題加以探討，並建立兩階段實驗設計模式，第一階段以部分因子實驗法篩選出顯著因子，第二階段以反應曲面法（Response Surface Methodology，RSM）加上中央合成設計 （Central Composite Design，CCD）與願望函數（Desirability Function）找出顯著因子之最佳解組合，並進一步找出適合之操作範圍，以確保製程能力（Process Index Capability）處於穩定狀態。

There is a tendency towards colorized Thin Film Transistor Liquid Crystal Display (TFT-LCD) undoubtedly. The color filter, which contains three fundamental colors of red, green, and blue, is an important and essential raw material for TFT-LCD. One panel of TFT-LCD is assembled by a pair of the same size of TFT Array and color filter, therefore, color filter with good quality is very important, it is significant influence to the performance of TFT-LCD. In the process of TFT-LCD assembly, the supports between thin film transistor and color filter substrate depend on the uniform distribution of spacer, it also keeps the gap between thin film transistor and color filter for injection liquid crystal. The content of photo spacer is photosensitive resin, photo spacer size and photo spacer precision can be controlled since it is manufactured by the mature photolithography process on the black matrix of color filter, one of the advantages of photo spacer is to prevent moving of bead type spacer to keep the good uniformity of cell gap, it also prevents light leakage around the spacer to get higher contrast. This research focuses on the problem of photo spacer process of color filter and builds two steps Design of Experiment method model. The first step is considering the all factors that will inference photo spacer process, apply the factional factorial experiment method to find out the critical factors. The second step applies Response Surface Methodology with Central Composite Design, the purpose is to find the optimum parameters setting and suitable process operation range to ensure process index capability.