本論文旨在利用濕式蝕刻法製備出矽角錐平台，並利用濺鍍法沉積與水熱法(Hydrothermal Growth, HTG)分別成長氧化鎳(Nickle Oxide, NiO)薄膜與奈米片於矽角錐平台上，結合延伸式閘極場效電晶體之架構(Extended-Gate Field-Effect Transistor, EGFET)應用於pH感測之開發。本研究所採用之濕式蝕刻技術製備矽角錐平台與HTG技術具低備製程成本、簡易、可大面積製備以及製備時間短等優點，且可藉由角錐平台所增加之表面積與HTG NiO奈米片之高感測面積的雙重面積提升效果，大幅強化吸附待測溶液中氫離子的能力，進而改善pH感測能力。
本論文之研究工作分為三部分，第一部分為藉由濕式蝕刻法KOH/IPA溶液製備出矽角錐平台，並藉由調變蝕刻溫度改變其表面形貌，探討不同蝕刻溫度蝕刻所得矽角錐表面形貌對pH感測特性之影響，比較並分析利用矽平面與最佳蝕刻參數所製備角錐平台pH感測器之特性。於pH感測特性量測上，本研究使用Keithley 2636A作為電特性之量測，EGFET則採用市售之CD4007UB n-MOSFET，參考電極為Ag/AgCl，量測溫度固定為300K，延伸式閘極與參考電極距離固定為2 cm。
第二部分旨在比較濺鍍NiO薄膜於平面與角錐粗化矽基板上的pH感測特性。藉由調變不同沉積時間觀察於兩種矽基板上的表面形貌變化，輔以SEM、及X-光繞射(X-Ray Diffraction, XRD)等材料分析，探討NiO薄膜之表面形貌與材料成分並比較其在pH量測特性之表現。
第三部分為利用水熱法製備NiO奈米片，觀察不同水熱成長時間在角錐粗化矽基板上的表面形貌變化。透過SEM觀察其表面形貌以及XRD與TEM材料分析。探討不同成長時間感測膜與退火溫度對pH感測特性之影響。實驗顯示，於所製備NiO奈米片pH感測器中，以水熱成長7.5小時於矽角錐基板上之NiO奈米片元件擁有最佳之感測特性。實驗結果顯示，於水熱成長7.5小時之Ni(OH)2奈米片元件，經在空氣氛圍下退火溫度400°C進行40分鐘熱退火處理，其pH靈敏度為56.5 mV/pH，線性度為0.999。於可靠度之遲滯效應與時漂效應之探討方面，實驗結果顯示最佳化結構元件於緩衝溶液pH 7→4→7→10→7量測循環中之遲滯電壓為5.88 mV，於緩衝溶液pH 7量之時漂值為1.03 mV/h，顯示所製備元件具有良好之感測特性與可靠度穩定性。
本論文所提以濕式蝕刻之矽角錐平台作為後續濺鍍法與水熱法製備NiO奈米片感測電極之pH感測器，可藉由角錐粗與奈米片所得之表面積增益有效改善元件之感測特性，亦具有製程成本低、簡易、製程時間短與大面積製備之優點，預期此元件於未來之pH感測器應用將極具潛力。

In this work, the use of Si (100) substrate with pyramidal cones is proposed for the RF sputtering of nickel oxide (NiO) thin film and hydrothermal growth of NiO nanosheets (NSs) to improve the pH sensing performance for the first time. With an optimized KOH based etching process at 90°C for 40 min, a surface area gain of around 91% can be obtained from the etched Si substrate. NiO thin film sputtered and NiO NSs hydrothermally grown on the proposed Si substrate were used as pH sensing electrodes, respectively. The pH sensing performance of the NiO thin film on the proposed Si at 100 watt, 1.1×10-2 torr and 40 minutes exhibits a pH sensing response of 52.87 mV/pH. NiO thin film replaced by the NiO NSs offers more surface area, The pH sensors based on NiO NSs synthesized at 90°C for 7.5 h shows a near Nernstian response of 56.5 mV/pH in a pH range 2-12 buffer solutions and a near perfect linearity of 0.999. It is attributed to the dual surface roughening scheme considerably increases the sensing area and, in turn, increases the amount of surface sites for H+ sensing to promote the sensing performance.

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