本實驗利用化學氣相沉積法(CVD)合成各種硫化鋅(ZnS)奈米結構，在實驗中成長出的ZnS奈米結構總共有四種，分別為:奈米線、奈米箭狀結構、奈米帶狀結構、奈米鋸齒狀結構。藉由不同的電子束能量做SEM成像可以發現越低kV數時，奈米結構之表面形貌越能清楚地顯現。由TEM可知ZnS奈米線為wurzite結構。ZnS奈米帶狀結構表面充滿選擇性蝕刻的痕跡，經TEM分析後確認為wurtzite結構。ZnS奈米箭狀結構在低倍率TEM影像上出現垂直於成長方向之亮暗條紋，經高解析TEM影像與雙束條件(two beam condition)之明暗視野像證明其亮暗條紋乃wurtzite與zinc blende結構交互轉變所造成之疊差。而ZnS奈米鋸齒狀結構為一雙晶(bi-crystal)結構，由wurtzite與zinc blende結構共同組成。
另外，本實驗也對ZnS與銅網之間的固態反應(solid state reaction)做探討，於450℃退火10分鐘後藉由TEM與STEM EDS mapping分析可發現銅元素由銅網擴散至ZnS奈米結構上，而nanobeam繞射分析可發現Cu2S相的形成，當於500℃退火3小時後，ZnS會轉變為Cu2S且由電子束繞射圖與高解析TEM分析可發現Cu2S之超晶格結構。
另外藉由控制退火時間與退火溫度可以控制銅元素擴散至ZnS奈米結構上的量，此結果已由EDS分析證實，由結果可知當退火溫度為450℃時，只要超過40分鐘ZnS便會轉變為Cu2S。
而由CL光譜並沒有出現ZnS摻雜(doping)銅之後的特殊發光，其512nm之發光來自硫的空缺(vacancies)，而538nm之發光來自表面的硫元素。
利用四點量測可發現ZnS奈米線之電阻率為10的3次方(Ω‧cm)，在400℃退火兩小時後電阻率並沒有明顯改變，而在500℃退火一小時後電阻率急遽地降低，由此可進一步證明Cu2S相的產生，而場效實驗則證明了利用固態反應得到之Cu2S奈米線為一p型半導體。

We use chemical vapor deposition to grow a variety of ZnS nanostructures. There are four types of nanostructures, including nanowires, nanoarrows, nanobelts and nanosaws. SEM images show that the lower electron beam energy, the clearer surface morphology of the nanostructures. The nanowires are of wurtzite structure. The nanobelts are full of etching signs, and crystallize in wurtzite structure. Through high resolution transmission electron microscopy and dark field imaging under two beam conditions, the bright and dark fringe contrast presence in the TEM images of the nanoarrows is demonstrated to be stacking faults resulted from the phase transformation between wurtzite and zinc blende structure. The nanosaws are of bi-crytal structures. The zinc blende and wurtzite structures coexsist in the nanosaws.
We also study the solid state reactions between ZnS nanostructures and conventional copper grid at elevated temperature. After annealing at 450℃ for 10 minutes, the diffusion of Copper from Copper grids into the nanostructure is apparant through TEM imaging and STEM EDS mapping. Nanobeam diffraction patterns indicate the formation of Cu2S . After annealing at 500℃ for 3 hours, the Cu2S nanostructures form with superlattices form, evidenced by the electron beam diffraction pattern and HRTEM imaing.
Diffusion of copper from copper grids to ZnS nanostructures was investigated as a function of annealing time and temperature. The amount of Cu diffusion can be controlled by annealing time and temperature, studied by EDS analysis. After annealing at 450℃ for 40 minutes, the ZnS nanostructures transform completely into Cu2S nanostructures.
CL spectrum shows no emissions resulted from the doping of copper in ZnS. The emission peak centered at 512nm is resulted from sulfur vacancies and the emission peak centered at 538nm is resulted from sulfur on the ZnS surface.
Four-point measurements show that the resistivity of the ZnS nanowires is about ten to the power of three (Ω‧cm). After annealing at 400 ℃ on the copper grids for two hours, the resistivity of the ZnS nanowires is unchanged. And after annealing at 500 ℃ on the copper grids for one hour, the resistivity decreases greatly, which further demonstrates the formation of copper sulfide. Field effect measurements show that the Cu2S nanowires derived by the solid state reaction are of p-type semiconductors.

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