本研究主要是利用COMSOL模擬加上實驗驗證來探討孔洞對氧化鋅奈米線之壓電性質的影響。本實驗步驟如下，先利用Sputter在矽基板上鍍一層ZnO seed layer，再使用化學浴沉積法成長氧化鋅奈米柱，通過改變前驅液的反應時間，可有效控制氧化鋅奈米線之長度，接著使用高溫爐管進行氫氣退火，透過調整氫氣退火時間來控制氧化鋅奈米線之孔隙率。
利用貴重儀器中心的掃描式電子顯微鏡(HITACHI SU8000,SEM)來觀察不同參數對氧化鋅奈米線之形貌、直徑、長度及孔隙率的影響，再使用穿透式電子顯微鏡(JEOL JEM-2100F-CS,TEM)來觀察氧化鋅奈米線內外孔之分布及數量，並使用壓電力顯微鏡(PFM)來量測孔洞對壓電係數之影響，最後使用原子力顯微鏡(HITACHI SPA400,AFM)分析孔隙率對壓電效應的影響，其結果與COMSOL模擬之趨勢呈現一致性。

This study investigates the piezopotential of porous & non-porous ZnO nanowire arrays, and the porous one shows the ultra-high enhancement from COMSOL simulations and experimental results. First, we growth ZnO seed layer on silicon substrate by sputter in room temperature, then growth ZnO NWs by chemical bath deposition method, followed by hydrogen annealing to create surface pores and inner pores. We use SEM(HITACHI SU8000) to see the morphology, including diameter, length, and porosity, then use TEM(JEOL JEM-2100F-CS) to see inner pores and surface roughness. From the COMSOL result, piezopotential is proportional to porosity both in normal and lateral force, which is consistence with AFM measurements.

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