本研究主要以非平衡態分子動力學模擬方法，探討碳化矽在不同奈米尺度薄膜之溫度及尺度效應，以及在缺陷散射機制下受溫度及尺度效應下的熱傳導係數，並延伸探討不同初始條件下奈米碳化矽薄膜的聲子傳輸情形，並探究其熱傳效果高低的成因。首先於理想碳化矽薄膜之模擬下，建立碳化矽薄膜完美分子晶體結構之模型，並直接改變其厚度及溫度，觀察其隨厚度及溫度之熱傳導係數變化，並利用聲子相關性觀察聲子在兩區域的振動模態是否相似，由此反映聲子傳遞之情形，聲子相關性越高表示聲子在兩區域之間所發生的散射越少，表示聲子能傳遞的能量越完整，而其中若低頻聲子之相關性越大，則會相對有較大的熱傳導係數。
於缺陷率的模擬下，首先改變整體模型之缺陷率，是利用固定薄膜厚度的情形下，以隨機抽取分子之方式將多種不同缺陷比率之分子移除，藉此模擬真實實驗條件下碳化矽薄膜以不完美的結構存在的狀況，並以具缺陷之碳化矽薄膜之模型下改變其厚度、溫度，觀察其熱傳導係數與完美碳化矽薄膜的比較，並探討在缺陷散射機制的影響下的聲子相關性的變化，藉以討論各類情況下影響熱傳導係數高低可能的成因。

This study mainly uses non-equilibrium molecular dynamics simulation methods to investigate the temperature and scale effects of silicon carbide in different nano-scale films, and compare the differences in thermal conductivity after adding defect scattering mechanisms. Using the phonon transmission behavior of silicon carbide nanofilms under different initial conditions, the reason for its heat transfer effect is discussed. We establish a model of the perfect molecular crystal structure of the silicon carbide thin film under the simulation of the ideal silicon carbide thin film, and directly change its thickness and temperature to observe the change of its thermal conductivity with the thickness and temperature, and use the phonon coherence to observe the phonon whether the vibration modes of the two regions are similar, which reflects the situation of phonon transmission. The higher the phonon coherence, the less the phonon scattering between the two regions, and the more complete the energy transferred by the phonon. Among them, the greater the coherence of low-frequency phonons, the greater the thermal conductivity.
In establishing the defect film model, the defect rate of the overall model is first changed. In the case of fixed film thickness, molecules with different defect ratios are removed by randomly selecting molecules to simulate the silicon carbide film under real experimental conditions. Under the condition of imperfect structure, we change its thickness and temperature under the model of defected silicon carbide thin film, observe the comparison of its thermal conductivity with perfect silicon carbide thin film, and discuss the phonon coherence changes under the influence of defect scattering mechanism. This result discusses the possible causes that affect the thermal conductivity in various situations.

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