臺灣博碩士論文加值系統

隨著半導體科技快速的發展，傳統光學微影技術在現有的ArF(波長為193奈米)，搭配許多精密解析度增益技術，在製作奈米等級線寬時已經將近到達其物理極限，並且也造成成本上的負擔。奈米壓印由於其高產量和低成本，在奈米結構和製程上的重要性與可行性，已在學術界和產業界造成廣泛的研究與討論，並且是奈米科技上重要的研究課題。雷射輔助直接壓印技術則是奈米壓印技術在近年來的重大突破；在雷射輔助直接壓印技術裡，我們使用KrF準分子脈衝雷射（雷射波長248奈米而脈衝時間為30奈秒）當作輔助材料加熱融化的熱源。並使用以做好微米或奈米等級圖案的高透光率石英當作母模，將石英母模跟欲壓印材料接觸並且預加壓力，而後從石英正上方施加準分子雷射，當基材產生融化現象時，預施壓力在基材上的石英母模會因為融化的矽在短時間內填滿模具上的圖案，並且重新成形。其間，僅耗時數百奈秒，製程快速；可以省去一般奈米壓印所需的蝕刻阻擋層的塗佈、加溫壓印，以及後續的蝕刻製程，直接複製母模之負向圖案在矽基板上面，大大的縮短奈米壓印的時間。從半導體製程而言，縮減了光阻塗佈、曝光、顯影及蝕刻等手續，也不需要昂貴高成本的解析度增益技術。
本文將研究雷射加工平台的建置，並且藉由設計平台來探討加工參數對於製程上的影響，包括了雷射能量密度(laser fluence)和壓印壓力對於壓印深度的影響，本文挑選雷射能量密度0.7∼1.2 J/cm2而壓印力量為2∼9 kg，藉以探討三者之間的互相影響。經由後續實驗的量測，壓印後的外觀及壓印深度與雷射能量密度及壓印壓力相關。

As the rapid development of semiconductor technology, the feature size which is smaller than 100nm has reached its limitation. At the present exposure wavelength, ArF （193nm in wavelength）, optical photolithography technique with several resolution- enhancement techniques has already reached its physical limitation and the escalating cost has become a burden for many companies. Nano-imprinting Lithography (NIL) has been considered as the most promising technique for nano-scaled fabrication and patterning. Recently, a new approach known as Laser-Assisted Direct Imprinting (LADI) has been proposed and demonstrated as an even more efficient way for direct nanofabrication and nanopatterning. In this study, we focused on silicon materials and utilized a single KrF excimer laser pulse (248 nm wavelength and 30 ns pulse duration) as the heating source. Molds of micro-scaled size have been prepared using conventional photolithography techniques. A working platform based on an Excimer Laser Micro-Machining system is constructed for LADI process. The influence of laser fluence and the imprinted pressure on the resulting structures was verifying by varying the laser fluence (0.7∼1.2 J/cm2) and the imprinted load (2∼9 kg). The results have shown that the morphology and the imprinted depth were directly related to the laser fluence and the imprinted pressure.

中文摘要...............................................I
Abstract..............................................II
致謝.................................................III
Contents..............................................IV
List of Tables........................................VI
List of Figures......................................VII
Symbols Descriptions.................................XIV


Chapter 1 Introduction
1.1 Preface............................................1
1.2 Literature Survey..................................3
1.3 Motivation........................................11
1.4 Thesis Outlines...................................14

Chapter 2 Experimental Procedure
2.1 Mold Fabrication..................................15
2.1.1 Beforehand Preparation.........................15
2.1.2 Photolithography...............................18
2.1.3 Dry etching and Dicing.........................21
2.2 Laser-Assisted Direct Imprinting (LADI)...........26
2.2.1 Excimer Laser Micro-Machining System...........26
2.2.2 Designed Working Platform......................29
2.2.3 Process for LADI...............................31

Chapter 3 Results and Discussions
3.1 Results...........................................33
3.1.1 Surface appearance.............................33
3.1.2 Imprinted depth................................44
3.2 Discussions.......................................50

Chapter 4 Conclusions and Future Perspective
4.1 Conclusions.......................................56
4.2 Future Perspective................................58

References............................................59
自述..................................................64

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