本論文研究是鹼土金屬Sr的矽化物SrSi2，藉由摻雜Al與Si的比例而形成SrSi2-xAlx (x=0,0.06,0.15,0.2)，為了了解其熱電性質，我們將這一類的合金置於溫度10～300K量測，量其熱導率、電阻率以及Seebeck coefficient。由實驗值得知，絕大部分的熱導是由晶格熱導率( )提供。並且發現晶格熱導率隨著摻雜Al/Si的比例減小，這是因為聲子的散射機制變大所致，而再去了解電子熱導率，有大幅的增加。而Seebeck coefficient測量SrSi2-xAlx顯示其值皆為正值，並且有達到140 mV/K。這個訊息顯示出合金的傳輸載子為電洞，而在摻雜Si之後Seebeck coefficient有大幅下降的趨勢。在室溫，比較熱導率、電阻率與Seebeck coefficient，雖然三個熱電性質在摻雜後都有下降的趨勢，但是Seebeck coefficient下降了一個數量級而其他還維持同一數量級，所以以 ，就可以知道ZT值是下降的趨勢。我們所做的SrSi2與較高ZT值的材料相比仍有一個級數差。

We report thermoelectric properties of SrSi2-xAlx(x=0,0.06,0.15,0.2) which is alkaline-earth metal Sr of silicides SrSi2 with Al substitution onto Si sites. We research thermal conductivity, electric resistivity as well as seebeck coefficient from 10K to room temperature. The result of experiment tell us that lattice thermal conductivity dominate thermal conductivity. We find that thermal conductivity decreases with the increase of doping level for enhancement of scattering process. By the way, electric thermal conductivity increase with the concentration of doping . The seebeck coefficient of SrSi2-xAlx is positive , and accomplish 140 mV/K. It is indicating that hole-type carriers dominate the heat transport. In normal temperature, reduction of thermal conductivity, electric resistivity accompany seebeck coefficient decreasing. Figure-of-meri descrese with incresing doping level.

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