層化高分子/液晶複合薄膜的電壓保持率與殘餘直流電壓特性

Voltage Holding Ratio and Residual-Direct-Current Characteristics in Stratified PolymerLiquid-Crystal Composite Films

胡建霆(Chien Ting-Hu)

指導教授 ： 李偉

中原大學/理學院/應用物理研究所/碩士(2009年)

https://doi.org/10.6840/cycu200901011

摘要

本論文旨在探討層化高分子/液晶薄膜的電壓保持率與殘餘直流電壓特性；即利用本實驗室所開發之自動化量測系統，測量液晶或高分子標準樣品與不同混合比例之非對稱層化高分子/液晶樣品的電壓保持率與殘壓值，以釐清層化樣品中各層材料的分別貢獻。
研究結果顯示：一、層化高分子/液晶複合薄膜的電壓保持率由高分子的比例所主導—當高分子含量愈高時，元件整體之電阻值上升，使電壓保持率愈高；二、層化高分子/液晶複合薄膜的殘餘直流電壓與高分子結構密不可分—高分子前驅物的含量會影響其受紫外光照射下聚合物的固化過程，當其比例愈高時，固化愈穩定且表面愈平整，這會抑制高分子層介面吸附離子雜質的能力，使殘餘直流電壓值變低；三、層化高分子/液晶元件的電流對電壓曲線圖與典型之純液晶元件大異其趣；高分子與液晶二者複合後的電流對電壓特性趨勢仍由高分子材料層所主導。

關鍵字

殘餘直流電壓 ； 層化高分子/液晶複合薄膜 ； 電壓保持率

並列摘要

Voltage holding ratio (VHR) and residual direct current (RDC) of stratified polymerliquid-crystal films are investigated in this thesis. The auto-measurement system developed in this laboratory is used to monitor the VHR and RDC in standard cells of either liquid crystal or polymer alone and in asymmetric ones of polymerliquid-crystal layer hybrid with various polymer contents, clarifying the contributions of the liquid-crystal and polymer layers separately to the VHR and RDC of the stratified films.
The thesis demonstrates: (1) the VHR of stratified polymerliquid- crystal films is dominated by the polymer concentration—the more the polymer content is, the higher the bulk resistance becomes, leading to the higher VHR; (2) the RDC of stratified samples depends on the polymeric structure—as the precursor concentration increases, the solidification process mitigates during photopolymerization and the polymeric surface becomes smoother, resulting in suppressed ion-adsorptive capability on the interface and, in turn, reducing the RDC; (3) the currentvoltage behavior of a stratified cell, again dictated by the polymer layer, is distinctive from that of a typical liquid-crystal cell.

並列關鍵字

Residual-Direct-Current ； phase separation composite films ； Voltage Holding Ratio

參考文獻

[1] V. Vorflusev and S. Kumar, “Phase-separated composite films for liquid crystal displays,” Science 283(19), 1903–1905 (1999).

[2] Q. Wang and S. Kumar, “Submillisecond switching of nematic liquid crystal in cells fabricated by anisotropic phase-separation of liquid crystal and polymer mixture,” Applied Physics Letters 86(7), 071119-1–3 (2005).

[3] Q. Wang, R. Guo, M. R. Daj, S-W. Kang, and S. Kumar, “Flexible plastic display fabricated using phase-separated composite films of liquid crystals,” Japanese Journal of Applied Physics 46(1), 299–303 (2007).

[4] R. Penterman, S. I. Klink, H. de Koning, G. Nisato, and D. J. Broer, “Single-substrate liquid crystal displays by photo-enforced stratification,” Nature 417(2), 55–58 (2002).

[5] Y.-H. Lin, H. Ren, S. Gauza, Y.-H. Wu, Y. Zhao, J. Fang, and S.-T. Wu,,“IPS-LCD using a glass substrate and an anisotropic polymer film,” Journal of Display Technology 2(1), 21–25 (2006).