近年來各種機電元件均趨於微型化，由於金屬在這些元件中大多扮演傳輸電子的角色，能夠快速又穩定的傳輸電子在各個元件之間對於整體電子產品的穩定性與可靠度有很大的影響。為瞭解這些微型化元件的性能與功能，奈米技術已成為當前研究的主流，而相關的研究課題和技術應用，也隨之出現。
奈米壓痕量測(Nanoindentation)技術可說是當下檢測奈米級材料最可信也是最有效的方法，利用此種技術可以量測材料在奈微米尺度之領域的基本機械性質例如薄膜的彈性模數(Young’s modulus)、硬度(Hardness)、潛變(Creep)等。但在奈米壓痕量測中，直接量得的數據是負載¬深度曲線，必須經過特定的轉換方法才能得到我們所需的機械性質，而在奈米尺度下，這樣的轉換機制並不明確，所以在奈米壓痕量測與機械性質之間的轉換仍存在許多尚待研究與探討的空間。
本實驗以分子動力學模擬各種探針在不同結晶面的基板壓痕的過程，藉此觀察壓痕過程中基板接觸形變的情況，並探討其內部差排產生的機制與差排的運動情形，最後希望可以了解在奈米尺度下奈米壓痕量測與機械性質轉換之間的關係。
而本實驗發現，在不同探針與基板的模擬情況中，探針形狀的不同只會影響差排圖案啟動的時間先後。而影響差排種類不同的原因來自於基板原子排列與探針原子排列的不同，這樣的差異則會影響壓痕過程中缺陷的結構，使得負載¬深度曲線呈現不同的特徵。由於在巨觀的壓痕實驗中，計算基板物理性質的考量因素往往只有探針的形狀以及接觸面積，當實驗的尺度漸漸小至奈米尺度之後，也必須將探針與基板的原子排列情形列入考慮的因素之中，藉此可以得到更精準的轉換數據。

In recent years, a variety of mechanical and electrical components are miniaturized. As metals play the most important role of these components due to the electronic transmission. The fast and stable transmission of electrons makes large effect in stability and reliability of these various components. To understand the performance of these miniaturized components and functions, nanotechnology has become the mainstream of current research.
Nanoindentation measurements technology can be the most trusted and most effective way to measure the mechanical physical properties of metals such as film elastic modulus (Young's modulus), hardness, creep and so on. However, in nanoindentation measurement, there are specific conversion methods to get the required mechanical and physical properties. In present, such conversion methods are not clear, so there are still many problems to solve.
In the thesis, we use MD simulation to simulate different probes and substrates interaction in nanoindentation, in order to observe the substrate deformation situation. In that way, we will investigate the internal mechanism of dislocation nucleation and movement. By doing so, we hope to understand the conversion relationship between the nanoindentation and the mechanical properties in nano-scale.
We found that the difference of probe shape will only affect the time that the dislocation patterns start to growth and the depth of the dislocation patterns. The factor to affect the types of the dislocation patterns are the atomic arrangement of the probe and the substrate and the different types of dislocation patterns will affect the mechanical properties of the substrate. In recent conversion methods, we usually take probe shape and contact area into consideration to get the mechanical properties. When the size shrinks down to nano-scale, however, we should take the atomic arrangement of the probe and the substrate into consideration to get the precise conversion.

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