濺鍍製程是現今許多高科技元件的關鍵技術，因此薄膜的基礎科學及相關製程技術的研發為現今學術界及產業界的重大課題。藉由電腦模擬薄膜製程，將可研究不同參數對於薄膜結構的影響與瞭解實驗中所無法觀察到的薄膜沈積型態演化過程。

本研究發展一個三維濺鍍薄膜的模擬系統，包括成核機制及成長機制兩部分的模擬。成核部分採用隨機亂數的計算方法，研究鍵結係數、捕捉半徑及臨界核大小對於成核型態的影響；在晶粒成長的部份，則採用等位函數法(Level Set Method)進行界面演化的運算，並依據濺鍍源分布型態計算表面沈積速度，以平均曲率計算晶界遷移速度。此外，本研究亦探討基板溫度、濺鍍源功率對於薄膜表面型態及晶粒型態的影響。

模擬結果顯示， 提高基板溫度，將使粒徑分布範圍減小，飽和成核密度降低，且使得薄膜晶粒的平均粒徑增大。提高濺鍍源功率則與提高基板溫度有相同的影響趨勢，但以基板溫度的影響較為顯著。在晶界遷移的模擬中，則觀察到當鄰近晶粒粒徑接近且曲率變化不大時，晶界將漸漸趨近於直線狀。

Sputter is a critical process for many high-end technology. Therefore, the fundamental basic science of sputter deposition and the related research of thin film process are the major subjects in industries and academia. With the simulation of sputter deposition, we can study how variables affect the film structures and understand the structural evolution which can’t be observed in experiments.

A three-dimensional simulation system of sputter deposition has been developed in this study. The mechanisms of nucleation and grain growth are both studied in the simulation. In nucleation stage, nucleation process is modeled using randomization method. Some nucleation variables like sticking coefficients, captured radii of clusters and critical nuclei size are considered in the simulation. In growth stage, the topographic evolution is modeled using level set methods and the deposition rate is calculated by angular distribution. The migration rate of grain boundary is calculated considering the mean curvature of grain boundary. The influences of substrate temperature and the power of sputtering source on morphology are studied, as well as that on the following morphology evolution of grain growth.

The simulation has shown the following results. Increasing substrate temperature will result in the narrower distribution of grain size, the lower density of saturated nucleation and the greater average diameter of thin film grain. The effect of increasing sputter power is similar with that of increasing substrate temperature; however, more remarkable influence of substrate temperature is observed in this study. In the simulation of grain boundary migration, we can find that when the grain size and curvature of neighbor grains are similar, the grain boundary will gradually shape into a straight line.

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