近年來石化燃料的消耗面臨枯竭以及氣候變遷，且人類對於能源的需求不斷增加，環保、低成本且高效率的新型能源成為重要的課題。本文研究熱電材料其中之一的硒化錫，探討藉由摻雜其他元素以達到提升熱電性質的潛力。
本文應用第一原理探討硒化錫摻雜鉛及碲元素，在不同濃度下之摻雜對於硒化錫摻雜成N型或是P型半導體之趨勢是否有影響。利用軟體Quantum Espresso及BoltzTraP進行電子結構及性質的計算，獲得電子傳導率及席貝克係數等數據，以計算本文著重的功率因子(Power　factor)的探討上。
本文研究結果顯示，若從各個方向來討論，在N型半導體方面，摻雜鉛濃度1.56%的功率因子在300K、500K及700K溫度條件下，其a方向與未摻雜之硒化錫相比分別提升8.514、5.65及2.41 。而摻雜碲元素在各種摻雜濃度及溫度條件下，對硒化錫的熱電性質沒有顯著的提升。

　Because of the lack of fossil fuels, climate change, and the demand of energy is increasing in recent years, how to find the kind of energy has character of eco-friendly、low cost and high efficiency is important. In this study, we investigate one of thermoelectric materials, SnSe, to research the potential of properties of thermoelectrics by doping other elements.
　　In this study, we investigate SnSe doping with Pb and Te elements by First Principle, respectively. With different doping percentage and elements, we study how the doping influence the trend of SnSe to become N-type or P-type semiconductor. We use Quantum Espresso and BoltzTraP to do the calculation of electric structure and properties, to get the electric conductivity and Seebeck coefficients, and we focus on the investigation of power factor, square of Seebeck coefficients times electric conductivity.
　　Our results show that SnSe doped with Pb of 1.56%, the power factor in N-tpye semiconductor and temperature at 300K, 500K, 700K, can increase 8.514, 5.65, 2.41 compare with undoped SnSe in a-axis, respectively. In our result, doped with Te elements don’t show obvious improvement on the properties of thermoelectrics in every doping percentage and temperature condition.

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