本論文使用分子動力學(Molecular Dynamics, MD)模擬鑽石圓柱衝頭對銀薄膜與不同溫度下銀/鈀非晶合金薄膜結構在銅基材的奈米壓印行為。探討其塑性變形機制與成型形貌，並改變方形陣列式衝頭節距、基材厚度以分析不同的晶體結構薄膜對壓印過程之干涉現象及底部回復現象。
模擬結果顯示，FCC的單晶薄膜結構，其壓印結果的形貌，是取決於差排滑動系統的方向性。在非晶合金薄膜壓印時，其塑性變形的滑動機構是靠原子間之自由體積的移動完成，不具有特定的方向性，但溫度接近室溫，衝頭給予的應變易引發相轉換，使材料朝結晶態發展；當溫度接近熔點，因溫度上升使得表面能效應與沾黏現象變得明顯，以致壓印溫度在玻璃轉換溫度附近，可得較佳的壓印形貌。在壓印過程中，材料會利用各自的塑變機制來降低材料內的應力場，使得衝頭節距的大小對於衝頭底部受力的影響不大；在衝頭側面切線力方面，當節距越小，衝頭內側對於原子的擠壓效應增加，導致衝頭側面切線力增加。不同基材厚度的條件下，增加基材的厚度，可降低背向應力對薄膜的影響，以減少成形孔底部的塑性回復量；但高溫下的非晶合金，還需考慮溫度效應。

This study applies molecular dynamics (MD) simulation to discuss nanoimprinting behaviors of cylindrical diamond punches to Ag thin films and Ag/Pd amorphous thin films with different temperatures. Besides, punch pitches and substrate thickness are varied to analyze interference and recover phenomena for different crystal-structure thin films.
The experimental results show that the imprinting topography of FCC single crystal thin films depends on slip directions of dislocation. As the imprinting temperature is close to room temperature, The amorphous material that slip plastic deformation mechanism is induced by free volume within atoms. As the imprinting temperature is close to room temperature, the phase transformation is caused by the punch. As closing to melting temperature, a surface-energy effect and adhesion are resulted from the raising temperature, leading a glass transition temperature to dominate the imprinting topography. During the imprinting process, plastic deformation of materials decreases stress fields. Hence, various pitches have little effects on normal force of punches. As decreasing pitches, an obvious squeezing effect increases tangential force of punches. Furthermore, plastic recover effects can be reduced by increasing substrate thickness, which lowers back stress on thin films. However, temperature effects should be concerned for amorphous alloys under high temperature.

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