摘要: | 本研究使用對稱型嵌段共聚物—聚苯乙烯-b-聚(甲基丙烯酸甲酯)混摻聚苯乙烯均聚物(PS21k-b-PMMA21k/PS6k),在不同的混摻比例、均聚物的分散係數(PDI)和熱回火溫度下,我們可以獲得不同奈米結構。 為了去除表面潤濕層並增加 PS 和 PMMA 之間的對比度,我們使用了氧氣等離子體蝕刻。 並利用光學顯微鏡(OM)、原子力顯微鏡(AFM)、掃描電子顯微鏡(SEM)、掠入射小角 X 射線散射(GISAXS)深入分析薄膜形態。 透過臨場(in-situ)可以探討在熱回火之自組裝行為,在量測不同入射角之方式(angle-dependent)可以研究結構及晶面特徵。透過均聚物PDI的不同,在PDI = 1.05及1.33可以獲得水平圓柱(Parallel cylinders, Cs//)的形貌,但PDI 1.5在70/30的混摻比例下結構會有所改變,並受到溫度的牽制。當溫度230 ℃會在薄膜表面形成單層穿孔層(Perforated layers, PLs //)結構,而內部維持水平圓柱,在270 ℃則會形成完整雙連續螺旋(Bicontinuous Double Gyroids, DG)結構。透過公式擬和水平圓柱的散射峰,能夠量化入射角、臨界角、q⊥方向貢獻以及穿透光與反射光之路徑,準確判斷晶面貢獻以及域間間距,更深入了解薄膜之結構。 ;We have demonstrated the symmetric weakly separated block copolymer, polystyrene-block-poly(methyl methacrylate)blended with homopolystyrene(PS21k-b-PMMA21k/PS6k). By using different blending ratios, homopolymer’s dispersity(PDI)and annealing temperatures, we obtained several nanostructures. To remove the surface wetting layer and to increase the contrast between PS and PMMA segments, we used oxygen plasma etching. Optical microscopy(OM), atomic force microscopy(AFM), scanning electron microscopy(SEM), grazing-incidence small-angle X-ray scattering(GISAXS)were also used for in-depth morphological analysis of thin films. Through in-situ GISAXS, the self-assembly behavior during thermal annealing can be investigated. The structures and crystal facet characteristics can be studied by angle-dependent GISAXS. Through quantitative analysis of angle-dependence GISAXS, we found that blend films favor a morphology of parallel cylinders(Cs//)when PS homopolymers of PDI=1.05 and 1.33 were mixed with the PS-b-PMMA at weight fractions of 70/30, 60/40 and 50/50. For PDI=1.5, perforated layers(PLs //) and bicontinuous double gyroids(DG)were obtained in blend films of P(S-b-MMA) and hPS of a weight fraction of 70/30. At 230 ℃, a surface layer of perforations formed on top of parallel cylinders. At 270 ℃, bicontinuous double gyroids formed. By fitting the q-scattering peaks of the horizontal cylinders through the formula, it is possible to quantify the incident angles, critical angles and diffraction spots along the q⊥ direction, thus allowing us to accurately determine the crystal plane contribution and interdomain spacing. |