臺灣博碩士論文加值系統

本論文研究目的是針對光聚合單體(photocurable monomer)與液晶混合製成液晶盒(liquid crystal cells)樣品，進行紫外光聚合反應以觀察所形成高分子聚合物網狀結構(polymer-network)對液晶分子配向之影響。在實驗液晶盒中光聚合單體之濃度比例為1至8 wt.%範圍的變化條件；而在光聚合的實驗條件，我們進行曝照固定紫外光強度與改變時間參數的變化，觀察實驗條件對液晶配向之影響。
實驗製程中所使用量測儀器，包括橢圓儀(ellipsometer)、原子力顯微鏡(atomic force microscope, AFM)、偏光顯微鏡(polarized optical microscope, POM)、掃描式電子顯微鏡(scanning electron microscope, SEM)及光穿透率-外加電壓系統量測光電的特性。
實驗結果發現，當NOA-65濃度比例提高時光穿透率呈現降低，當含量5 wt.%以上時，容易形成高分子聚合物的薄膜而且薄膜上纖維狀的高分子聚合物是無序性的方向與液晶分子之間引力後，致於液晶分子失去整齊性之配向目的。

In this thesis, we studied the influence of liquid crystal alignment effected by photocured polymer-network in the monomer mixed liquid crystal cells. The monomer concentration of liquid crystal cells were various in range of 1~8 wt.%. For ultraviolet light exposure processes, we variously controlled the exposure time in condition of same exposure intensity for all experimental cells in order to observe the correlation between polymer-network and liquid crystal molecules alignment.

We used many instruments to measure and observe the experimental results including ellipsometer, atomic force microscope (AFM), polarized optical microscope (POM), scanning electron microscope (SEM) and the laboratory setup for electro-optical measurement.

Meanwhile, rising the NOA-65 concentration induces lower light transmission. When the concentration is higher than 5 wt.%, photocured
monomer forms a composite film and disorder direction morphology of polymer-network. It’s disadvantageous to improve the liquid crystal molecules alignment .

第一章 緒論　1
1-1 前言　1
1-2 研究動機與目的 　2
1-3 研究方法　3
第二章 材料特性介紹　6
2-1 液晶的物性與光電特性　6
2-1-1 常用液晶之三種型態　6
2-1-2 液晶分子的方位秩序參數　6
2-1-3 液晶的雙折射性　8
2-1-4 液晶盒之臨界電壓　11
2-1-5 液晶盒之反應時間　16
2-2 聚亞醯胺高分子的特性　18
2-3 光聚合高分子的特性　19
第三章 實驗方法及量測設備　21
3-1 液晶盒製作步驟與方法　21
3-1-1 ITO玻璃基板清洗　22
3-1-2 塗佈配向膜層　23
3-1-3 摩擦配向製程(rubbing alignment process)　25
3-1-4 液晶混合物注入與組合及封膠　27
3-1-5 紫外光曝照液晶盒　29
3-2 樣品的微觀量測設備　31
3-2-1 橢圓儀(ellipsometer)　31
3-2-2 原子力顯微鏡(atomic force microscope, AFM)　35
3-2-3 偏光顯微鏡(polarized optical microscope, POM) 36
3-2-4 光穿透率-外加電壓的量測系統　37
3-2-5 掃描式電子顯微鏡(scanning electron microscope, SEM) 38
第四章 實驗結果與分析　39
4-1 橢圓儀的量測結果與分析　39
4-2 原子力顯微鏡的量測結果與分析　46
4-3 偏光顯微鏡的量測結果與分析　52
4-4 光穿透率-外加電壓的量測結果與分析　64
4-5 掃描式電子顯微鏡的量測結果與分析　70
第五章 總結與展望　95
5-1 總結　95
5-2 展望　98
參考文獻　99

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