過渡金屬元素鈷(Co)的單一矽化合物(monosiliside)在摻雜鋁(Al)後形成合金CoSi1-xAlx，測量此合金隨溫度變化的電阻率(ρ)、熱電係數(S)、熱傳導率(κ)。由測得的數據可以得知當Al取代了Si的晶格位置後使得電阻率(ρ)跟晶格熱傳導率(κL)有顯著的減小。從理論上的分析可以看出，晶格熱傳導率(κL)的減小主要是來自聲子與晶格缺陷散射的增強。當x ≧ 0.05的時候，CoSi1-xAlx的熱電係數由負值轉變為正值，並且出現熱電係數的極大值。而Al的加入導致了電洞摻雜效應的產生，使得處於膺能隙中央附近的費米能階(Fermi-level)向下偏移。雖然熱電效能因Al的摻雜而大幅改進，但是本實驗CoSi1-xAlx樣品之ZT值跟目前公認的熱電材料比較，大約還有一個數量級的差距。

　　We report the effect of Al on the temperature-dependent electrical resistivity, Seebeck coefficient, as well as thermal conductivity in the binary compound cobalt monosilicide. It is found that the substitution of Al onto the Si sites causes a dramatic decrease in the electrical resistivity and lattice thermal conductivity. A theoretical analysis indicated that from point-defect scattering of the phonons. For x ≧ 0.05 in the CoSi1-xAlx system, the Seebeck coefficient changes sign from negative to positive, accompanied by the appearance of a broad maximum. These features are associated with the change in the electronic band structure, where the Fermi level shifts downward from the center of the pseudogap due to hole-doping effect. While the thermoelectric performance improves with increasing Al substitution, the largest figure-of-merit ZT value among these alloys is still an order of magnitude lower than conventional thermoelectric materials.

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