當壓電材料受到外界應力時會產生壓電電勢(piezopotential)，再結合半導體材料的特性之下，能將機械能(mechanical energy)轉換為電能的新興電子元件「壓電奈米發電機」(piezoelectric nanogenerator)油然而生；藉由施力來調控行為的裝置「壓電電子」(piezotronics)也同樣是與次世代接軌的重要發明。
本研究裡使用了極穩定的材料合成方法「水熱法」。首先將(001)矽基板經標準程序清洗乾淨，接著使用濺鍍儀在基板鍍上膜厚約200奈米的氧化鋅薄膜作為種子層，隨後配置以同莫耳數比例混合的醋酸鋅與環六亞甲基四胺(HMT)的溶液，在攝氏八十度的低溫下進行九小時氧化鋅奈米線的成長。最後也是最重要的氫氣退火─生成非連續性奈米孔洞結構的關鍵步驟，在加熱爐裡以攝氏550度進行不同的持溫時間對氧化鋅奈米線造孔。
以單根奈米線為基礎進行的電性量測，以及大面積的直流式電流圖(current mapping)都透過原子力顯微鏡在接觸模式(contact mode)底下操作。結果指出，孔洞氧化鋅的輸出電流遠高於原生的奈米線，顯示壓電效率已被提升。同樣的現象也可以在隨施壓不同而變化的電流─電壓曲線圖上觀察到。針對內孔與外孔，正文將透過分析金屬半導體接面的蕭特基能障、載子濃度變化、氫氣─氧化鋅的反應，研究其對壓電效應的影響，最後再以模擬確認並做出總結。

Advances in ZnO nanowires based nanogenerators and strain-gated transistors were achieved by creating pores by hydrogen annealing. The nanogenerators made of porous ZnO nanowires, upon scanning an conductive AFM tip demonstrate 23 times enhancement in output performance. Furthermore, the sensitivity of a single nanowire based strain-gated transistor has been improved as well. We suggest that there are two critical factors contributing to the striking experimental results, which are pores-induced piezoelectric effect enhancement and surface state modification. By analyzing the current-voltage characteristics in conjunction with simulations, detailed mechanisms are discussed. The work demonstrates that porous nanostructures can potentially enhance energy harvesting and pressure sensing for many applications such as portable self-powered nano-device and touch panel related electronics.

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