在下一代奈米級模板可以由溶劑蒸氣退火過程來探討嵌段共聚物薄膜非常重要的有序化機制。然而，在有機溶劑環境底下難以將薄膜樣品從無序到有序相進行原位觀測形貌的演進。一般來說，會使用散射方法來研究形貌演變對應的倒空間影像，但是沒有可以應用的實空間成像技術，尤其是經由穿透式電子顯微鏡的觀察。本研究的目標，將新穎的環境穿透式電子顯微鏡實驗方法運用在檢視於甲苯蒸氣退火中的自組裝行為，就能夠發現到聚苯乙烯-聚二甲基矽氧烷(PS-PDMS)星形嵌段共聚高分子薄膜的微結構發展。伴隨著定製氣體樣品桿與氣體晶片的特殊設計，可以實現在溶劑蒸氣退火底下利用穿透式電子顯微鏡觀察薄膜樣品。這是首次在有機溶劑環境的條件中，透過溶劑膨脹狀態下觀測由無序到有序相(層狀或圓柱)的形貌演變過程。因此，使用此求新求變的氣體樣品桿能夠創造甲苯環境穿透式電子顯微鏡的分析設備，而且此系統提供了千載難逢的機會，就是在有機溶劑環境下去研究時間解析的相變化行為。

Exploring the ordering mechanism of block copolymer (BCP) thin films from solvent vapor annealing (SVA) is highly essential in next-generation nanopatterning. However, it is difficult to carry out in-situ morphological evolution of the BCP thin films from disorder to ordered phase under organic solvent environment. Usually, scattering methods are exploited for the examination of the corresponding morphological evolution through reciprocal-space imaging whereas no feasible real-space imaging can be applied, in particular, transmission electron microscopy (TEM) observations. In this study, we aim to suggest a novel approach by using environmental TEM observations for the examination of the development of nanostructured thin films from the self-assembly of polystyrene-block-polydimethylsiloxane (PS-PDMS) star BCP under toluene for the SVA. With the design of gas chips and a customized gas holder, it is feasible to address the BCP thin films under SVA for TEM observations. The morphological evolution from disorder to ordered phases (lamellae or cylinder) can be directly visualized under solvent-swollen state at ambient condition for the first time. As a result, it provides the great opportunity to examine the time-resolved phase transformation under organic solvent environment by using this new sample holder for environmental TEM observations.

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