摘要
三維奈米圖案 (3D Nanopatterning) 的製程中廣泛運用嵌段共聚物自組裝形成多層特徵的微結構已成為微機電系統的主流趨勢。此研究提出了一種有效且簡便的方法，用於開發三維奈米圖案化的新平臺技術。主要策略是使用含高Flory-Huggins Interaction Parameter (χ) 和擁有層板結構的聚苯乙烯-嵌段-聚二甲基矽氧烷 (PS-b-PDMS) 透過溶劑退火的方式來進行順序自組裝。 透過使用PS選擇性溶劑，加上相對溶劑蒸氣壓的調節，可以誘導嵌段共聚物薄膜的自組裝，從而產生各種有序的奈米結構。有趣的是，獨特且單層的六邊形穿孔層板結構 (HPL) 可在薄膜表層對稱的條件下形成。在反應離子蝕刻後，可以提供具有六邊形孔陣列的二氧化矽單塊。隨後，隨著相對溶劑蒸氣壓的增加，平行圓柱結構的單層可形成並排列在以上六邊形孔陣列的二氧化矽單塊上。在第二次的反應離子蝕刻後，形成線對孔的雙層結構。此外，隨著第二層薄膜厚度的減小，可以在具有平行圓柱陣列的單層薄膜上創建雙層的平行圓柱的正交奈米網格。此外，通過使用強 PS 選擇性溶劑進行退火，可以形成具有六邊形堆積球體的單層，並也可排列在以上六邊形孔陣列的二氧化矽單塊，形成點在孔的雙層結構。透過不同奈米微結構層的疊合，此方法成功創建了一種製造三維納米圖案的新平臺技術，適用於微機電系統應用中。

Abstract
Herein, this work aims to suggest an effective and facile method for the development of a new platform technology of 3D nanopatterning through sequential self-assembly of lamellae-forming polystyrene-block-polydimethylsiloxane (PS-b-PDMS) block copolymer (BCP) with a high Flory-Huggins interaction parameter (χ) from solvent annealing. With the use of PS selective solvent, the tuning of relative solvent vapor pressure may induce the self-assembly of BCP thin film, giving rise to a variety of ordered nanostructures. Interestingly, a unique hexagonally perforated lamellae (HPL) monolayer can be formed at symmetric boundary system, and thus served as an excellent candidate to give a well-defined two-dimensional SiO2 monolith with hexagonal hole array after reactive ion etching (RIE) treatment. Subsequently, with the increase of relative solvent vapor pressure, parallel cylinder-structured monolayer can be addressed on the SiO2 monolith fabricated above, giving line-on-hole nanopattern after 2nd RIE treatment. Moreover, with the reduction of film thickness of second layer, it is possible to create an orthogonal nanomesh of the forming parallel cylinders addressing onto a monolayer film with parallel cylinder array. Furthermore, with selection of strongly PS-selective solvent for annealing, it is feasible to give the formation of monolayer with hexagonal packed spheres that can also be addressed onto the SiO2 monolith fabricated above, giving dot-in-hole nanopattern. With the combination of forming nanostructured phases addressing one after another, it is feasible to create a new platform technology for fabrication of 3D nanopatterns in the nano-MEMS applications

Contents
Abstract I
Contents III
Table Caption VI
Figure Caption VII
Chapter 1 Introduction 1
1.1 Block Copolymers (BCPs) 1
1.1.1 Block Copolymers in Bulk State 1
1.1.2 Block Copolymers in Thin Film State 3
1.1.3 Self-Assembly of High χ Silicon-Containing Block Copolymers
………………………………………………………………………...7
1.2 Controlled Orientation of Block Copolymers Self-Assembly in Thin
Film 10
1.2.1 Thermal Annealing 11
1.2.2 Solvent Annealing 12
1.3 Factors Affecting Solvent Annealing Process 17
1.3.1 Solvent Selectivity 17
1.3.2 Solvent Vapor Pressure 19
1.3.3 Solvent Annealing Time 21
1.3.4 Substrate Surface Effects 23
1.4 3D Nanopatterning 25
1.4.1 Layering of Block Copolymers Patterns 25
1.4.2 Cross-linking for Sequential Deposition of Block Copolymers Patterns 27
1.4.3 Immobilization of Block Copolymers Patterns via Hybridization Methods for Subsequent Deposition of Block Copolymers Structure..30
Chapter 2 Objectives 35
Chapter 3 Experimental 37
3.1 Synthesis of PS-b-PDMS BCPs 37
3.2 Sample Preparation 40
3.2.1 Sample Preparation for PS-b-PDMS Bulk Samples 40
3.2.2 Preparation of PS-b-PDMS Thin Film 40
3.2.3 Substrate Functionalization via Grafting Approach 41
3.2.4 Characterization of Solvent Selectivity 41
3.2.5 Thin Film Morphology of PS-b-PDMS in Solvent Annealing 42
3.2.6 Sequential Self-Assembly of PS-b-PDMS on Topographic Patterned SiO2 43
3.3 Instrumentation 44
3.3.1 Transmission Electron Microscopy (TEM) 44
3.3.2 Small-Angle X-ray Scattering (SAXS) 45
3.3.3 Spectral Reflectometer (SR) 45
3.3.4 High Resolution X-ray Photoelectron Spectroscopy (HRXPS).. 46
3.3.5 Reactive Ion Etching (RIE) 46
3.3.6 Field-Emission Scanning Electron Microscopy (FESEM) 48
3.3.7 Atomic Force Microscope (AFM) 48
3.3.8 Focused Ion Beam (FIB) 48
Chapter 4 Results and Discussion 49
4.1 PS-b-PDMS Bulk from Solution Casting 49
4.2 Solvent Selectivity of Chlorobenzene 49
4.3 Effect of Relative Solvent Vapor Pressure on PS-b-PDMS Monolayer Self-Assembly 51
4.4 Substrate Functionalization via Grafting 58
4.5 Controlled Self-Assembly of PS-b-PDMS Monolayer on Functionalized Substrate 61
4.6 Monolayer with Spherical Texture from Solvent Annealing 71
4.7 Fabrication of Double-Layer Nanopatterns 72
Chapter 5 Conclusions and Prospective 83
Chapter 6 References 86

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