金屬直接奈米壓印之成型研究

Study of the Metallic Pattern Formation by means of Direction Nanoimprint

呂盈締(Ying-Ti Lu)

指導教授 ： 宋震國

國立清華大學/工學院/動力機械工程學系/碩士(2006年)

摘要

本論文主要研究金屬直接奈米壓印，利用奈米結構圖案製作之矽模具，對鋁薄膜進行圖形轉印，若能將模具圖形毫不失真的複製到鋁製薄膜上，達到高保真度的成型結果，則可稱為極佳的壓印品質。論文在討論壓印品質之前，先對奈米直接金屬壓印之成型機制做探討，利用分子動力學模擬壓印過程，根據應力分佈情形觀察表面效應、基材效應與應力鬆弛等現象，以及過程中所產生之塑性原子來觀察滑移系統與回彈現象。接著進行薄膜厚度、模具模穴寬度與節距比、以及深寬比三項參數之分子動力學模擬與各種相關實驗。模擬中以塑性原子比例、填充率、回彈比例與成型結果比例四項討論影響壓印品質之原因；實驗中利用成型寬度比例與成型高度比例兩種方式進行成型結果與模具對照壓印品質之探討，並藉由模擬來解釋實驗結果。
由實驗結果對照模擬結果，可以得到以下結論，薄膜厚度愈薄，由於基材效應造成填充率較低、成型結果較差；模穴寬度與節距比愈大，填充率較低、成型高度較差，但模穴內應力較小因此成型寬度較好；高深寬比模具，填充率低、成型結果差。

關鍵字

奈米壓印 ； 金屬薄膜 ； 原子級應力 ； 圖案成型 ； 分子動力學

並列摘要

The thesis proposes an alternative method which can transfers nano-scale patterns to aluminum (Al) thin films directly. If the template can perfectly reproduce on metallic thin films, then it is called high fidelity patterns and the best quality of nanoimprint. Molecular dynamics simulation is utilized to simulate the nanoimprint process and via examining the atomic stress, the surface effect, substrate effect and stress relaxation are discussed. From the plastic atoms produced by nanoimprint process, the slip system and the springback phenomenon can be observed. The simulations and the experiments are implemented for three parameters, the thickness of the metallic thin film, the mold space to a periodic width and the aspect ratio of the mold-teeth. In the simulation, the effect of nanoimprint quality will be discussed by plastic-atom ratio, filling rate, springback ratio, and pattern-formation ratio. In the experiments, the difference between the pattern on the thin film and on the mold, meant the quality of nanoimprint, is presented by the formed pattern of width and the formed pattern of height.
From the simulation and experimental results, the following phenomena can be observed. When the thickness of the film decreases, the filling rate is lower owing to substrate effect and it induces the worse formed pattern. With increasing the mold space to the periodic width, the filling rate decreases and the formed pattern of height is shorter. But the formed pattern of width is better because of lower stress in the mold space during imprinting. For high aspect ratio mold, the filling rate is lower and the formed pattern is worse.

並列關鍵字

nanoimprint ； metallic thin films ； atomic stress ； pattern-formation ； molecular dynamics simulation

參考文獻

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