本論文研究在一般玻璃基板上成長大面積平面顯示器用高性能氧化鋁/氧化鉿(Al2O3/HfO2)堆疊絕緣層下閘極增強式(enhancement-mode)氧化鋅雙層通道透明薄膜電晶體。我們使用氧化鋅/氧化鋅鎂為通道層，並用氧化鋅鋁來做源極與汲極。電晶體製作皆使用射頻磁控濺鍍 (Radio Frequency magnetron sputtering)沉積在室溫下完成。氧化鋁和氧化鉿組成的雙層閘極絕緣能有效降低閘極漏電流。氧化鋅摻雜鎂可以加寬能隙及增加電阻率故用來作為上通道層以降低薄膜電晶體的關電流(off-current)。下通道主要作為電晶體導通時的路徑，故使用具有高導電度的純氧化鋅來增加開電流(on-current)。藉由雙層通道的設計可以同時降低off-current及提高開關電流比。
藉由調整厚度比例的雙層通道及使用堆疊堆疊絕緣層，吾人找出最佳的元件(W/L =500µm/50µm)特性，為：透明度>80%，最小的關電流為1.91×10-10A，最大開關電流比為6.86×106及場效載子遷移率約為2 cm2/Vs。相較於傳統單層閘極絕緣及單層通道氧化鋅薄膜電晶體，雙層通道及雙層閘極絕緣者可提高100倍開關電流比。比起一般以發表的透明氧化鋅薄膜電晶體皆需具有耐高溫的玻璃基板，本研究所發展出的雙層通道及雙層閘極絕緣透明式氧化鋅薄膜電晶體不但性能高，且擁有單一製程及可在室溫下於一般玻璃基板成長的製作簡便及成本低的優點，故更適合於未來大型尺寸平面顯示器的運用。

In this thesis, an enhancement-mode Zinc oxide (ZnO)-based and bottom gate double channel transparent thin film transistor (TTFT) with Al2O3/ HfO2 stack gate is developed on glass substrate. We use the ZnO based materials for all of layers i.e., ZnO/ZnO:Mg as active layer, Al2O3/ HfO2 as gate dielectric and ZnO:Al as source-drain electrode. Besides, all of layers are deposited by RF magnetron sputtering at room temperature.
The high κ stack gate including Al2O3 and HfO2 could effectively suppress gate leakage current. Besides, ZnO:Mg and ZnO are used respectively as top and button channel. The ZnO:Mg is ZnO doped with Mg , which could increase energy gap and resistivity, thus reducing the off current, and resulting in a higher on-off current ratio. By optimizing the top/ button channel thickness and use of the high κ stack gate, we obtain the performances of the TFT as; field-effect mobility ~ 2 cm2/Vs , minimum off current ~1.91×10-10A, on-off current ratio ~6.86×106, optical transparency >80%.Compare to the reported ZnO based transparent TFTs prepared on special glass substrates, the developed highκ stack gate double channel ZnO TFT has the advantages of simpler preparation and lower cost, thus is more suitable for future advanced large dimension flat panel display applications.

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