隨著電晶體越做越小，具有超高載子遷移率的超薄膜材料已是元件製作中必不可少的材料特性，然而傳統的矽基材並不能達成以上的要求。因此，擁有高載子遷移率、寬能隙以及極大的面積對體積比的二維材料，成為了研究主流。

在眾多新穎的二維材料中，我利用熱化學氣相沉積成長的硒氧化鉍Bi2O2Se晶體，即是具有良好的電性特性、光特性、容易成長，以及於環境中展現出高穩定性的材料。

此篇碩士論文，是我以熱化學氣相沉積系統來成長硒氧化鉍Bi2O2Se的研究。透過水平三區爐管的使用來達成精準控溫，並且調變不同的製程參數，如樣品擺放位置、溫度、製程時間等等，成功地沉積出了邊長超過100微米之Bi2O2Se晶體，並以光學顯微鏡、原子力顯微鏡以及拉曼系統作為觀測並檢測實驗結果。

在成長最新穎的二維材料硒氧化鉍Bi2O2Se中，我除了探索硒氧化鉍Bi2O2Se成長與其前驅物的關係，也在製程了解了製程時間與晶體成長的大小並無絕對的關係。同時，我還發現了Bi2O2Se具有之特殊的晶體二次成長機制，以及於大氣中、極無氧環境下的不穩定溫度。
關鍵字:Bi2O2Se、化學氣相沉積、二次成長機制、熱穩定度

Bi2O2Se is an emerging 2-D material with promising potential for futuristic semiconductor electronics. However, chemically vapor deposition of monolayer and few-layer films on desirable substrates for practical applications is difficult and only few research groups have successfully synthesized it in the past several years. In this paper, we successfully synthesized the Bi2O2Se crystal with the domain size larger than 100 um. The quality of grown Bi2O2Se crystals was measured by OM, Raman spectroscopy, AFM. In addition, we reported the self-termination of the crystal growth process and the decomposition of unstable Bi2O2Se even at temperature below the favorable crystal growth temperature when vapor concentrations of precursors are none or insufficient. The findings are expected to lead researchers to invent better growth processes in order to realize its excellent properties.
Key words: Bi2O2Se, CVD, Secondary crystal growth, Thermal Stability

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