近年來許多光電、通訊、電腦週邊、生醫、燃料電池等產業之零組件，由於材料特性需求或尺寸精微化，而使得射出成形技術無法被運用，本文提出之微奈米級金屬材料壓印成形技術，正可以提供上述需求的部份解答。奈米壓印(Nanoimprint)一般被認為是製造100nm以下結構最有潛力的方法之一；而有別於目前主流之奈米壓印技術，本文並不使用光蝕刻製程且被壓印之薄膜亦非「光阻材料」而為「金屬材料」。金屬薄膜壓印成形技術尚屬於未開發之園地，其力學機制、尺寸效應(Length scale effect)與製程也有待研究。
本文首先利用分子動力學來模擬奈米壓印製程，藉由改變模具線寬及金屬薄膜厚度以研究尺寸效應，並探討該尺寸效應對金屬薄膜之強度、硬度、基材效應、液靜壓區、塑性變形及模具線寬之成形性…等之影響，以上模擬結果再依據材料學及力學理論進行分析。結果顯示，模具線寬大小及金屬薄膜厚薄對奈米壓印成形的好壞均有顯著的影響。在實驗研究方面，本文涵蓋了金屬薄膜製備、奈米壓痕薄膜機械性質量測、電子束與光蝕刻奈米模具製作、奈米壓印機台之金屬壓印、以至於使用SEM、FESEM、AFM等量測成品之表面形貌等。實驗結果也符合分子動力學模擬之趨勢，顯示尺寸效應在金屬薄膜奈米壓印成形製程中是一個相當重要的製程因素。本文亦將相關參數加以變化進行模擬與實驗，其參數分析的結果將有助於壓印製程規劃與模具設計。

Recent development of opto-electronic and communication products, computer peripheral equipment, bio-medical devices, has resulted in increasing demands for metallic nano/micro structures. Nanoimprint is considered as one of the most potential processes for manufacturing nanostructures that have characteristic size less than 100 nm. Different from currently prevailing hot-embossing nanoimprint processes that imprint patterns on photo-resist materials and then employ lithography, this thesis proposes a method that directly transfers patterns on metallic thin films. To the best of our knowledge, there is no similar research on the formation mechanism of our proposed nanoimprint process, so the mechanics and length-scale effect must be investigated.
This study utilizes molecular dynamics to simulate the nanoimprint process and to study the length-scale effect by varying the pattern width of the mold and the thickness of the thin film. In addition, the strength, hardness, substrate effect, hydrostatic zone, plastic deformation, etc., are analyzed on the basis of fundamental theories of material and mechanics.
Moreover, an experimental study is also performed, which includes preparation of metallic thin film, characterization of material properties by nano-indentation, fabrication of molds by e-beam lithography as well as photo lithography, pattern formation by imprinting, and measurement of surface topology by SEM, FESEM and AFM. In consistence with the trend obtained from molecular dynamic simulation, experimental results further demonstrate that the length-scale effect is one of the important factors governing the quality of formation. Finally, a parametric study is conducted by both simulation and experiment; the results can provide useful information for the design of the mold and imprinting process.

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