本論文使用分子動力學(Molecular Dynamicx, MD)模擬鑽石方柱衝頭對銀薄膜內含有雜質缺陷，以及雙晶粒銀薄膜試片進行奈米轉印分析。探討轉印製程的塑性變形機制、成型孔形貌與底部回復現象。其中單衝頭轉印之試片其薄膜內的雜質缺陷是設置於方形衝頭的兩側，而雙衝頭轉印之試片其薄膜內的雜質缺陷是設置於衝頭之間，用以觀察雜質對於變形機制的影響。雙晶粒銀薄膜之模擬試片為(100)-(11 ̅0)晶面所結合而成，衝頭壓印位置皆在薄膜之晶界處，用以探討不同晶面所形成的晶界對於成型孔之影響。此外，改變衝頭間距進行奈米轉印，探討衝頭間距對轉印品質之影響。
模擬結果顯示，FCC的銀薄膜結構在壓印過程中，差排會受到雜質缺陷的干涉，使得差排滑移受到阻礙，進而影響成型孔之形貌。在雙晶粒銀薄膜之奈米轉印過程中，晶界亦會影響差排之滑移，隨著衝頭持續下壓，晶界會因為表面能之差異而產生遷移現象。在雙衝頭奈米轉印過程中，雜質顆粒會影響衝頭之間薄膜表面的形貌，若間距太小雙衝頭間之薄膜會產生凹陷的現象。

In this study, molecular dynamics (MD) are used to simulate the nanoimprinting behaviors of Ag thin films with impurities using a cuboid diamond punch. Additionally, nanoimprinting behaviors of a bi-crystal silver film was also discussed. Wherein the single punch nanoimprinting acted to specimen, in which two impurities was set at the both side of the punch, separately. For double punches nanoimprinting, the silver film contained an impurity located between the punches in order to explore the effect of impurity on the deformation mechanism.
The specimen with bi-crystal silver thin film were constructed by (001)_(110) and (001)_(111) crystal. The imprinting position is located at the grain boundary of the silver thin film, so the effect of grain boundary on the geometrical characteristics of the formed hole could be investigated.
In addition, the effect of the pitch of the punches was changed to study the influence of nanoimprinting. The effect of the impurity defect on nanoimprinting behaviors with double punches was also investigated.
The simulation results show that the thin film structure of the FCC, the appearance of the forming hole is depended on the crystal orientation. In the indentation process, the sliding of the dislocation will be impeded by the impurity, resulting in dislocations piled up, thus affecting the shape of the formed hole.
In the process of nanoimprinting of bi-crystal silver thin film, the grain boundary will also affect the slippage of the dislocation. As the punch continued to press, the grain boundary will migrated due to the different of surface energies of the various crystal planes. As the results, the grain boundary effect for the plastic deformation mechanisms and the shape of the formed hole are obviously. In the process of double-punch nanoimprinting, impurity particles affect the formed hole that result in a cave located at the silver surface between the punches.

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