本論文主要是探討奈米碳管結合氧化銦形成的複合薄膜，經不同溫度熱氧化以及調配不同濃度的碳管溶液，最後經過微波電漿處理，以EGFET的架構，應用於pH酸鹼度的感測器，進行I-V曲線圖、pH感測度量測，並探討感測度與材料特性之間的關聯性。
本實驗主要是先以直流濺鍍系統鍍上銦薄膜於玻璃基板上，再以氮氣噴槍噴鍍以調配好的奈米碳管溶液在銦薄膜之上，最後再進行通入氮氣與氧氣的熱氧化處理；其次在將製程順序改變，先噴鍍碳管在玻璃基板上，然後再鍍銦在其上，之後再量測並觀察之；之後嘗試以微波電漿對元件進行處理，通入氫氣以及氧氣於試片上；最後再以場發射電子顯微鏡、拉曼光譜儀、X光繞射分析儀、傅立葉紅外線光譜儀分析材料的表面特性。
靈敏度量測是在暗房以及室溫下進行，分別外加電壓於參考電極0~3V(VREF)、MOSFET之汲極0.3V(VDS)，並觀察MOSFET之汲極電流(IDS)變化；本實驗結果顯示，以1mg重的奈米碳管粉末所調配的溶液，經過400°C的熱氧化處理，其靈敏度最佳為36.54mV/pH。
最後可得到在適當的製程參數下，以熱方式進行元件的氧化，其奈米碳管中一定比例的缺陷空位(defect sites)以及較高結晶程度的氧化銦，是影響此複合薄膜進行酸鹼感測的重要因素；而以微波電漿進行處理，對奈米碳管也有很大的影響。

The carbon nanotube/indium oxide(CNT/In2O3) nanostructure are grown on glass by DC sputter system and spray coating technique. The thin film with a EGFET structure are performed in the pH solution between pH 2 and pH 12 .
Using different thermal oxidation temperature and different concentration of carbon nanotube suspension, it shows that the best pH sensitivity is 36.43mV/pH and the best experimental condition is at the thermal oxidation temperature of 400°C with a carbon nanotube powder of 1mg weight in the spraying solution. By using Raman spectroscopy and XRD, this shows that the proper defect sites of carbon nanotube and higher crystallinity of indium oxide presents better pH sensitivity.
Microwave plasma with hydrogen and oxygen is also used as post-treatment and pre-treatment processes for the devices. It is found that the devices with different treatment condition can effectively influence the sensing performance.
The device is simple to make and with a low cost compared to other techniques, giving it a potential to the mass production in the disposable pH sensor applications.

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