由於熱電裝置需要低導熱性的半導體結構，但目前廣泛研究的超 晶格結構製程複雜，導致價格過高，使得熱電裝置推廣受限。而多孔 性奈米線能有效增加聲子阻抗、降低熱傳導係數，且製程較簡單、成 本低，希望能應用在熱電裝置上，提高其應用價值。
本文討論孔隙大小、散射面積及孔隙間距對多孔隙奈米線的熱傳 導係數影響，得到以下結論:
1. 尺寸效應使得孔隙邊界上存在能量密度較高的區域，降低熱傳導 係數。
2. 材料中增加絕熱孔隙使聲子碰撞邊界後發生散射，攔阻聲子運 動，使熱傳能力降低，孔隙尺寸越大，熱傳導係數越低。
3. 在同樣孔隙率的情況下，孔隙數越多，散射面積就越大，熱傳導 係數就越低。
4. 當尺寸效應發生時，產生局部高(低)溫區域會影響孔隙散射面積，
因此孔隙間距會對熱傳導係數產生影響。
對於未來研究方向有以下幾點建議:
1. 建立三維的物理模型，使模擬更接近真實的奈米結構。
2. 當尺寸小於 10nm 時，量子效應就會更明顯，因此希望能建立波 的模型，來描述更小尺寸的奈米結構。
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