利用熱蒸鍍法經由VLS成長機制在爐管內成長硒化鋅奈米線，以硒化鋅粉末作為前驅物置於管內，2、5及10奈米金薄膜的(100)矽基板做為成長基板，利用金顆粒作為成核催化點，使奈米線經由VLS成長機制生長，由此機制生成的奈米線能有良好的結晶性及準直性。透過控制不同的實驗參數觀察奈米線的生長變化，其中的變因包含：前驅物的溫度、成長溫度、成長壓力、載流氣體、金膜厚度、成長位置以及成長時間。比較完其變因對奈米線造成的的影響，選出最佳的成長條件下生成的奈米線，對其做一系列的分析及探討，其中最佳生長條件下生成的奈米線，線長大約20至50微米，直徑大概60奈米，且都有良好的均勻度及準直性。分析的部分，分成材料性質分析及光電分析。透過場發射掃描式電子顯微鏡觀察硒化鋅奈米線的表面構型及一些基本性質；X光繞射儀及穿透式電子顯微鏡了解硒化鋅奈米線的晶體結構，得知硒化鋅奈米線的結構是纖鋅礦結構，利用EDS知道奈米線的成分比例，進而證明此成長機制是透過VLS機制生成；使用陰極發光光譜儀及紫外-可見光反射式光譜儀分析硒化鋅奈米線的光學性質，包括能隙及內部發光效應；拉曼分析則是了解硒化鋅奈米線的震動特性，進而得知此材料的性質。最後，把硒化鋅奈米線均勻地灑在鍍有第一層電極圖案的基板上，再經由FIB製作成場效電晶體裝置，利用四點探針量測的方法測量其電流-電壓特性曲線，分析其電阻率等特性，由於使用FIB製作電極，會使奈米線受到鎵離子的轟擊，造成鎵離子參雜的情形發生,進而改變奈米線的性質，使其電阻下降及形狀的改變。透過了解這些基本特性，對硒化鋅奈米線有更進一步的認識，對之後不同元件製作及應用上好的基礎及正向的幫助。

ZnSe nanowires (NWs) were synthesized by using a thermal evaporation method in a vacuum-sealed quartz tube inside a tube furnace. NWs were used ZnSe powder as a precursor to grow on silicon (100) substrates coated with different thickness 2, 5, and 10 nm Au catalysts film. The growth mechanism of NWs is vapor-liquid-solid (VLS) mechanism. It will help us to get the good crystallinity and less defect in the NWs. Moreover, we will observe the different condition of NWs by controlling the temperature of precursor, temperature of growth area, pressure, carrier gas, thickness of Au film, position of substrate and growth time of NWs. Combination of above conditions, the length of appropriate NWs we need is about 20-50 μm, and the dimeter is around 60 nm. Furthermore, the morphorlogy of NWs is uniform and straight. ZnSe NWs were characterized by field-emission scanning electron microscope (FE-SEM). X-ray diffractometer (XRD), and transmission electron microscope (TEM) use to observe the morphology and crystal structure of NWs. The structure of ZnSe NWs is zinc-blende structure. Also, EDS is used to prove the NWs is grown by VLS mechanism. Cathodoluminescence (CL) and ultraviolet–visible (UV-Vis) spectroscopy observe the optical property of NWs, and Raman spectroscopy also observes the characteristic of ZnSe NWs. After the characteristic analysis of ZnSe NWs, NWs were fabricated as single NW FET device by using focus ion beam (FIB). Use 4-point probe and 2-point probe measurements to measure I-V curve of ZnSe NW in order to study the electrical property of single NW. The conductivity is almost metallic conductor behavior. This result indicated that the ZnSe NWs were doped by Ga ion through FIB bombard, it caused the low resistivity of NW.

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