本實驗中以分子束磊晶系統(MBE)變溫成長合金薄膜Bi2Te3-xSex於Al203（0001）基板上，並利用臨場RHEED、AFM和XRD量測樣品表面與結構，確認樣品具有為良好單晶C軸優先取向且長程結構非常良好，且表面平坦的單晶薄膜，於本實驗變溫區間成長樣品，並不影響其長程結構，僅有表面特性的差異，並以XRD分析與XPS比例分析確認其薄膜合金比例為Bi2Te2Se，最後由拉曼光譜可以觀察到三種震盪模式，並發現有別以往文獻的拉曼光譜，顯示Bi2Te2Se合金薄膜是有極佳的結構；電子結構方面，由ARPES證實合金薄膜確實為拓樸絕緣體，並嘗試調變合金Bi2Te3-xSex薄膜比例，藉此觀察費米能級的移動與導帶電子貢獻的多寡；最後量測電子傳輸性質，希望能觀察到如文獻Bi2Te2Se合金薄膜有最高的電阻率，以及較低的載子濃度。

This study systemically investigates the structural and electric transport properties of Bi2Te3-xSex topological insulator alloys by varying the growth temperature of Bi2Te3-xSex and fixed the Bi:Te:Se flux ratio using molecular beam epitaxy (MBE). The surfaces of the alloys exhibit terrace-like quintuple layers and their sizes vary with the Te/Se ratio and the size of the characteristic triangular terraces of the Bi2Te3-xSex films decreases monotonically with the Se content increases. The lattice constant decreases linearly with the degree of Se doping concentration. All the Bi2Te3-xSex films have good structures and surfaces. The surface carrier concentration of the Bi2Te3-xSex film exhibits the largest surface concentration and the film resistivity reaches a maximum when Te:Se = 2:1. Optimal atomic and electronic structures as well as the electrical transport properties of Bi2Te3-xSex thin film alloys can be obtained by fine-tuned growth conditions, suggesting that Bi2Te3-xSex thin film alloy with this ratio is an excellent template for doping and investigating the properties of topological insulators.

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