本實驗探討摻雜釩之氧化鋅奈米柱的合成與特性分析，與其元件之壓力敏感度測試，首先以磁控濺鍍(R.F. sputtering)法在P-type矽基板上沉積氧化鋅晶種層，厚度約為100奈米，再用水熱法製備沿C-軸方向成長之釩摻雜的氧化鋅奈米柱，並觀察摻雜不同釩濃度對其形態及光學性質與壓電表現的影響。
在氧化鋅中摻雜釩的主要目的為提升壓電性質並提高載子濃度，以便應用於壓力感測元件，本實驗透過調控水熱法生長溶液中五氧化二釩濃度來達到不同程度的摻雜，從掃瞄式電子顯微鏡與X 射線繞射儀之結果可以得知在五氧化二釩濃度範圍從0到1.25mM皆為纖鋅礦結構，並無其他相出現且皆具有良好[002]優選方位，代表釩是以摻雜的方式進入氧化鋅晶體，但在濃度超過0.75mM後有部分出現二維片狀結構，此結構對後續元件表現有不良影響，透過螢光光譜儀分析可以觀察到0.5-1.25mM範圍內氧化鋅UV峰有明顯藍移現象，與預期N型釩摻雜之結果相符。適量的釩摻雜有助於抑制部分本質缺陷，從共振拉曼可以看到0-0.75mM範圍缺陷有減少趨勢並在0.75mM達到最佳，從化學鍵結及元素成分分析(XPS、EDS)可以觀察到釩的原子百分比有隨著提高五氧化二釩濃度而增加，五價釩離子比例也有此趨勢且在0.75mM以上時該比例大過於五價釩離子。
本實驗元件設計由一PN接面(p-Si與n-Zn)與一蕭特基接面(n-Zn與Au)組成，由於氧化鋅之壓電效應，壓電勢所造成之能帶傾斜會使載子往PN接面處飄移從而增加電流，而蕭特基接面則是提高閾值電壓，比較受壓與未受壓之電流增加量即可得知氧化鋅壓電效應強弱，並計算元件之電流敏感度與壓力敏感度，本實驗在0.75mM樣品中取得最佳輸出表現，電流敏感度最大值172%，壓力敏感度最大值230.3MPa-1。

We successfully fabricated well-aligned vanadium-doped ZnO nanorods array on (111) p-type silicon substrate by hydrothermal method as a pressure sensor. All samples had [0002] preferential orientation. By adjusting the concentration of V2O5 in the grow solution , We can get different doping level of the ZnO nanorods. Characterize the different doping concentration ZnO nanorods to observe the affects due to vanadium doping. Vanadium commonly exists in oxidation states of V3+ and V5+. V3+ has a larger ionic radius, while V5+ has a smaller ionic radius compared to zinc (Zn). We compared the XPS data that at 0.75mM [V2O5] V5+ percentage start becoming higher than V3+ percentage. EDS also showed an increasing trend of V at%. Resonance Raman scattering(RRS) also showed that 0.75mM [V2O5] has best crystal quality. Summing those benefits, 0.75mM [V2O5] is the most optimal condition to grow Vanadium doped ZnO nanorods array and its current sensitivity reaches 172% and stress sensitivity reaches 230.3MPa-1.

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