以光纖式原子力顯微術研究液晶配向膜在矽晶片表面之物理性質

Abstract

本論文是以光纖式原子力顯微術研究液晶配向膜在矽晶片表面之物理性質。我們所使用的兩種液晶配向膜為：DMOAP (N,N-dimethyl-N-octadecyl-3-aminopropyltrimethoxysilyl chloride)及MAP (N-methyl-3-aminopropyltrimethoxysilane)，並混和不同體積濃度比例之配向膜，作為本實驗之樣品。我們量測光纖探針與配向膜表面接近時，探針振幅隨樣品距離變化的情形，以研究液晶配向膜之間的差異性。我們並改變探針驅動電壓，分辨在不同的探針振幅下對作用力的影響。 由實驗結果與數據分析顯示：(1)以光纖式原子力顯微鏡掃瞄液晶配向膜在矽晶片表面上的影像，所得的結果非常相似；(2) 在探針振幅與距離關係量測實驗中，樣品接近探針時所受的作用力影響範圍較遠離時小；(3) 當樣品接觸探針後，因受表面黏滯性的影響，探針振幅在遠離的過程中會比較遲緩；(4) 探針驅動電壓的改變與量測到探針振幅的訊號應成正比關係；(5) DMOAP表面作用力影響範圍大於MAP，而其他混和不同比例的作用力影響範圍在DMOAP與MAP之間。

In this thesis, we use atomic force microscopy with fiber probing tip to study the liquid crystal alignment agents coated on silicone surface. The alignment agents we studied are DMOAP (N, N-dimethyl-N-octadecyl-3- aminopropyltrimethoxysilyl chloride), MAP (N- methyl- 3- aminopropyltrimethoxysilane) and the mixture of them with different percent. We have varied the driving voltage of the tip to study the tip oscillation amplitude offset on the surface-tip interaction. The results show that:(1) the surfaces morphology are similar between these surfaces, (2) the interacting range of approaching process are shorter than leaving process, (3) after the tip has touched the surfaces, there are viscosity to make the interacting range becoming large, (4) the driving voltage of the tip are proportional to the oscillation amplitude of the tip, (5) the DMOAP surface show larger interacting range than the MAP surface, the mixture surfaces are between DMOAP and MAP.