我們在矽基材上研究對稱型弱分離嵌段高分子—聚(苯乙烯-b-甲基丙烯酸甲酯)混摻低分子量均聚物—聚苯乙烯之薄膜(PS21-b-PMMA21/PS6，下標表示分子量(kg/mol))，探討薄膜混摻系統在固定75/25比例之下，利用熱退火處理使高分子薄膜自組裝形成奈米結構。透過氧氣等離子蝕刻移除薄膜表面潤濕層，以光學顯微鏡(OM)、掃描式電子顯微鏡(SEM)以及低掠角小角度X光散射儀 (GISAXS)深入探討分析。透過臨場(in-situ)和非臨場(ex-situ)實驗數據與理論計算，探討薄膜在熱回火前後之自組裝行為及其形態，透過SEM影像觀察到薄膜表面為六角堆疊排列之點狀，而側視圖則顯示點狀或是水平排列的柱子，並且藉由晶面計算發現在本研究中混摻薄膜結構為穿孔層與水平圓柱相競爭共存，其中，薄膜在表面上優先形成穿孔層、在內部形成rectangular排列之水平圓柱，而非AB排列或是ABC排列。;We have demonstrated morphological observations and structural characterization for thin films of a symmetric, weakly segregated poly(styrene-block-methyl methacrylate), PS21-b-PMMA21 block copolymer blended with a low-molecular-weight homopolystyrene, PS6, on the silicon substrate. The subscripts denote the molecular weight in the unit of kg/mole. The PS21-b-PMMA21/PS6 blends were prepared at a constant weight fraction ratio of 75/25. The polymer films are capable of forming self-assembled nanostructures by thermal annealing. The wetting layer on the surface of the films was removed by oxygen plasma etching for further analysis. The prepared films were characterized with an optical microscope (OM), scanning electron microscope (SEM), and grazing-incidence small-angle X-ray scattering (GISAXS). The phase behavior and morphologies of self-assembly films with and without thermal annealing were characterized by in-situ and ex-situ GISAXS, morphological observations, and theoretical calculations. Top-view SEM images show that the surface of the films is enriched with dots of hexagonal arrays. Side-view SEM images show a morphology of parallel cylinders. This study shows that a thin layer of perforations preferentially formed on the surface and parallel cylinders formed inside the film for the blend films. The parallel cylinders inside the films have rectangular arrays rather than AB or ABC stacks.
