近年來，生物感測器之成長與應用已蓬勃發展於各個領域，例如醫藥與健康、化工領域、食品工業以及環境監測等；有鑑於此，本論文係利用射頻濺鍍法製備氧化鎳感測膜，應用於離子感測電極上，並結合金屬-氧化物-半導體場效電晶體以形成氧化鎳酸鹼離子延伸式閘極場效電晶體，取代傳統之閘極離子感測場電晶體，其具製作簡便、價格低廉之特性，可朝拋棄式感測器發展，提高在臨床醫療之實用性。緊接著，將感測元件置於不同酸鹼溶液中，藉由半導體參數分析儀測量感測元件之電流-電壓特性曲線，以探討不同濺鍍參數和沉積後高溫退火下氧化鎳感測薄膜對於酸鹼離子的感測特性。實驗結果顯示氧化鎳薄膜具有良好之氫離子感測度，且線性度佳，可應用於酸鹼離子檢測。為了與氧化鎳感測薄膜作比較，氧化銦錫及氧化鋅材料之酸鹼感測特性也將進行一系列之探討與分析。
接著再以原子力顯微鏡，X光薄膜繞射分析儀，化學分析電子光譜儀，掃瞄式電子顯微鏡等，進行薄膜結構之分析。
最後，利用黃光微影及熱蒸鍍技術沉積指叉狀電極於藍寶石基板上並結合氧化鎳感測薄膜，以製備電阻式氣體感測器。由實驗結果可知，氧化鎳材料具備檢測氨氣和氫氣的能力。尤其在高溫時，元件呈現更短的響應時間及更高的感測靈敏度。

In recent years, the development and application of biosensors have expanded in various fields such as medicine, chemical, food industry and environmental monitoring. In this study, the nickel oxide thin films were fabricated by radio frequency (RF) magnetron sputtering technology to be applied in the ion sensing electrode. Also, the thin film structure was connected with metal-oxide-semiconductor field-effect transistors (MOSFETs) to transform the EGFET (extended gate field-effect transistors). Due to the advantages of low-cost, facile process and simple extended-gate structure, the ion-sensitive field effect transistors (ISFETs) would be replaced by EGFET. Moreover, the separative structure is suitable for the applications on disposable pH sensors and clinical medicines. Afterwards, the semiconductor parameter analyzer system was utilized to measure the current-voltage (I-V) curves. Besides, the sensing properties of NiO pH-EGFETs under different sputtering conditions and post-deposition annealing temperatures were also investigated. Experimentally, NiO EGFETs possess the excellent pH sensitivity and linearity, indicating that the NiO EGFETs gives a promise for high-performance pH sensing applications. Finally, in order to understand pH sensing characteristics of semiconducting material, the ITO and ZnO materials would be discussed and analyzed.
By a series of atomic force microscope (AFM), x-ray diffraction (XRD), electron spectroscope for chemical analysis (ESCA), and scanning electron microscope (SEM) measurements, the compositions and structures of thin films can be obtained.
Finally, the conventional photolithography and thermal evaporation were employed to fabricate the interdigitated electrodes on the sapphire substrates. The NiO membrane have successfully been deposited on the substrate to form the NiO-based chemiresistor-type gas sensors. Experimentally, NiO materials show the sensing response not only to ammonia gas but also to hydrogen gas. The studieddevice also exhibits the short response time and high sensitivity at high temperatures.

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