本研究分別探討接枝在矽基材表面之高分子接枝層之微結構以及利用此高分子接枝層進一步調控對稱型雙嵌段共聚物薄膜之層狀微相奈米結構之排向探討。 第一部份，探討接枝在矽基材表面之高分子接枝層之微結構相形態。此研究利用尾端接有氫氧基之聚苯乙烯均聚物(polystyrene, PS)、聚甲基丙烯酸甲酯均聚物(poly(methyl methacrylate), PMMA))及其兩成份混摻體(binary blends:PS/PMMA)，進行化學接枝(grafting)方法改質矽基材表面。或是利用(加入)低分子量對稱型聚苯乙烯聚甲基丙烯酸甲酯雙嵌段共聚物塗佈於矽基材上，進行物理錨定(anchoring)方法，錨定於矽晶基材上。並藉由三成份混摻體進行矽基材表面改質。進一步利用光學顯微鏡，觀察高分子接枝層薄膜之表面除潤形貌。並利用X光反射量測高分子之接枝層薄膜厚度並定量分析高分子之接枝密度。並利用原子力顯微鏡觀察表面高分子接枝層之表面形貌，建立高分子混摻體(兩成份PS/PMMA或是三成份PS/PMMA/P(S-b-MMA)混摻)接枝層之組成與形態之關係。其實驗結果顯示高分子接枝層之表面形貌，受到混摻組成不同，而呈現不同的表面形貌。分別有波浪狀形貌(ripple)結構及類似顆粒狀(dimple)形貌之結構。進而加入低分子量之雙嵌段共聚物，亦可使表面呈波浪狀表面形貌。 第二部份利用分子接枝層進一步調控高分子量對稱型雙嵌段共聚物之層狀微相奈米結構之排向。由於對稱型雙嵌段共聚物層狀奈米結構受高分子接枝層與薄膜厚度的影響，分別會呈現水平排向、垂直排向以及混合排向。分別由原子力顯微鏡觀察以及低掠角X光散射實驗量測，可清楚觀察雙嵌段共聚物薄膜的表面與內部之層狀奈米結構之排向。 In this thesis, I explored the surface morphologies of grafted layers of low-molecular-weight homopolymers (PS and PMMA) or anchored ones of low-molecular-weight diblock copolymer (P(S-b-MMA)) on top of SiOx/Si. The grafted layers of mixed binary homopolymers (PS/PMMA) of various compositions or those of ternary blends (PS/PMMA/P(S-b-MMA) of various fractions were also investigated for comparisons. The surface morphologies and height profiles were characterized by using atomic force microscopy (AFM), X-ray reflectivity (XRR), and optical microscopy (OM). Grafted PS with a high grafting density on SiOx/Si was found to have a homogenously smooth surface, indicative of a brush conformation. The AFM image of grafted PMMA with a relative density on SiOx/Si displayed the formation of uniform PMMA clusters. The clustering of grafted PMMA chains was ascribed to an inter-chain affinity among the polar carboxyl groups of PMMA chains. By contrast, anchored P(S-b-MMA) revealed a ripple-like morphology. For grafted layers of binary PS/PMMA and ternary PS/PMMA/P(S-b-MMA), their surface morphologies varied with the mixed compositions. The surface morphology was dominantly governed by the major component in binary or ternary mixtures. Next, by using grazing-incident small-angle scattering (GISAXS) I further investigated the orientation of lamellar nanodomains within thin films of symmetric P(S-b-MMA) of high molecular weight on silicon substrates with tunable polymer-substrate interfacial fields. The varied surface fields of silicon substrates were prepared by grafting a layer of short PS or PMMA chains, or by anchoring a layer of short P(S-b-MMA) chains. It was demonstrated that in most cases, mixed orientations of vertical and parallel lamellae were present in P(S-b-MMA) thin films. Only substrates coated with end-anchoring P(S-b-MMA) chains led to a vertical orientation of lamellae existing through the whole film thickness.
