近年來缺電問題日益嚴重，伴隨疫情、戰爭、能源轉型，綠能產業的發展逐漸獲得重視，許多研究致力於研發節能、儲能、以及產能的裝置，而無論是作為壓電奈米發電機、或是壓電閘極電晶體元件，都是值得作深入研究應用的領域。
然而為了改進裝置效能，對於壓電效應的原理探討和測量也是不可或缺的，利用先輩的壓電效應領域研究作為基礎，結合實際量測趨勢，解釋元件中的變化，最終應用於壓力感測元件。
本研究選擇透明玻璃作為基板，以利之後可以延伸至光電效應之量測，而壓電薄膜材料選擇具有寬能隙(3.3eV)和c軸擇優取向的氧化鋅(ZnO)作為材料，配合一邊選擇歐姆接觸(Ohmic contact)的氧化銦錫(ITO)電極，另一邊選擇鉑(Pt)的電極作為蕭特基接觸(Schottky contact)的電極，以利觀察氧化鋅薄膜的壓電效應作用在元件上造成的變化。
利用SEM觀察材料表面平整度以及氧化鋅的膜厚，和利用XRD分析氧化鋅結晶性，以及結晶方向。並利用電流-電壓量測(I-V)、電容-電壓量測(C-V)、電容-時間(C-t)、和電流-時間(I-t)等電性分析得到的數據作探討和比較，配合能帶圖以及等效電路的幫助，了解材料受不同力量時，因壓電效應在氧化鋅表面累積的壓電電荷，造成的蕭特基能障(Schottky barrier height)改變、電流輸出、電壓輸出、電容變化。最後配合C-V的結果，研究基於元件構造所假設的等效電路，以及產生的壓電電容和空乏層形成之電容的串並聯情形。並探討作為電容式壓電感測器之表現和可行性，以及具有較大漏電流元件對於壓力感測上之影響。

This work aims to gain deep understanding of piezotronics devices operations based on ZnO Schottky diodes. The devices start with ZnO thin film deposition by sputtering on ITO/Glass substrate followed by Pt top electrode deposition to form Schottky contact. In order to visualize the operational mechanism of piezotronics in real time involving electron transportation inside ZnO while applying external forces, I-V, C-V, I-t, V-t, C-t methodologies are adopted. By further analyzing I-V and C-V curves, carrier dynamics and important parameters across the Schottky junction can be derived. Accordingly, we can investigate how piezo-charges are generated in response to external forces and the interplay between the induced piezo-potential and Schottky contact formation at the interface through dynamic carrier transport. Furthermore, the dynamic response mechanism of free carriers with charged ions from piezotronics effect can be investigated by measuring CV curves with time. Understanding the mechanism fully could help us improve the performance of our piezotronics devices.

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