本文利用金屬直接奈米壓印製程，製作奈米等級鋁金屬結構，並且藉由分子動力學模擬，討論在各種幾何與製程參數 下，模具之受力狀況；參數包含模具線寬節距比與薄膜厚度以及不同下壓速度，並且假定模具與薄膜間剪應力為摩擦力之作用，因此在分子動力學模擬中，觀察模具兩側表面原子之受力，來說明奈米壓印製程中摩擦對模具之影響，另外上述提及幾何因子與製程參數不僅摩擦力受到影響同時對於成型品質也隨之改變。
　　為了確認分子動力學模擬的結果，實驗上則是採用電子束製作奈米結構的矽模具，並使用金屬直接奈米壓印在不同薄膜厚度之鋁薄膜，得到奈米級微結構，壓印完成後利用原子力顯微鏡以及電子顯微鏡觀察所得到金屬幾何結構，並使用奈米壓痕機量測所需薄膜性質及壓印環境，藉由不同幾何結構之模具與不同厚度之薄膜，在成型結果與模擬結果上，其定性分析成一致現象；因此在未來也許能提供奈米壓印製程調校與壓印機台設計時之參考。

This thesis presents a study on the forces generated between the mold and thin film and their impacts on the formation of nano-scale structures on aluminum thin film by using direct nanoimprint. Molecular dynamics (MD) simulation is first employed to investigate how the forces acting on the mold in different geometrical and fabricating conditions. The former includes the thin-film thickness and the ratio of line width and pitch of the patterns, while the latter is the imprinting speed. Since we assume that the shear force between two contacting surfaces only causes the friction force, we select two layers of atoms above the bottom two layers from the side of the mold to calculate the friction force in order to differentiate from the plowing force. In addition, the aforementioned geometrical and fabricating factors that influence the friction force, which, in turn, affects the quality of formation are studied systematically.
For the verification of MD simulation results, we conduct the nanoindentation and nanoimprint experiments correspondingly. The mold and aluminum thin film are first fabricated. Then, we characterize the material properties of the thin film by using nanoindentation and measure the geometrical profiles of both mold and thin film by using SEM and AFM. We then perform nanoindentation and nanoimprint experiments on the thin films with various thicknesses by different molds. Then, observe the patterns being imprinted on the thin film. Consequently, the results of MD simulation and experiment correspond well, that may provide valuable guidelines for the design of direct nanoimprint.

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