本論文以超音波噴塗熱裂解法製備高效能二氧化錫摻雜鎂薄膜電晶體。論文中探討了包含了使用超音波噴塗熱裂解法沉積二氧化錫摻雜鎂薄膜的優勢、摻雜鎂後對二氧化錫內部晶格氧鍵解比例的影響以及主動層薄膜在高溫快速熱退火後內部缺陷的含量變化對薄膜電晶體之電性影響。最後嘗試了以超音波噴塗熱裂解法製作堆疊二氧化鈦和氧化鋁對氧化層與主動層介面品質的影響。共有三種構造在我們的研究中實現與比較。第一種為使用氧化鋁為氧化層和二氧化錫為主動層的結構，轉換特性可達到開關電流比1.79×108、次臨界擺幅203.5mV/dec、臨界電壓1.20V、場效電子遷移率82.8cm2/V-s和負閘極偏壓照光下臨界電壓偏移-1.00V。第二種為使用氧化鋁為氧化層和二氧化錫摻雜鎂作為主動層的結構，轉換特性可達到開關電流比1.46×109、次臨界擺幅173.3 mV/dec、臨界電壓1.15V、場效電子遷移率95.7cm2/V-s和負閘極偏壓照光下臨界電壓偏移-0.45V。第三種為使用二氧化鈦/氧化鋁堆疊成氧化層和二氧化錫摻雜鎂作為主動層的結構，轉換特性可達到開關電流比7.99×108、次臨界擺幅167. 5mV/dec、臨界電壓0.20V、場效電子遷移率130.0cm2/V-s和負閘極偏壓照光下臨界電壓偏移-0.40V。
鎂摻雜後產生較高的場效電子遷移率、較小次臨界擺幅和負閘極偏壓照光測試下較小的臨界電壓偏移。歸因於鎂有助於增加氧儲存能力，使介面間的缺陷降低，利於高濃度載子有效傳遞，進而使薄膜特性提升。更進一步的加入二氧化鈦堆疊，可以發現特性又有了進一步的提升，歸因於其有效的限制非晶氧化鋁晶粒生長尺寸。與結晶性主動層尺寸的差距變小，介面品質因此有效提升。
本實驗成功以超音波噴塗熱裂解法製備高性能二氧化錫摻雜鎂薄膜電晶體，此方法沉積出來的薄膜在市場具有極大的競爭力，因為其製程成本低和在非真空環境下進行。在元件電性方面擁有高電子遷移率、常關模式操作(臨界電壓大於0)、高開關電流比及高穩定性等優點，使在下次世代大面積面板產業應用中極具潛力，可望在未來市面上被應用。

In our thesis, the high-performance magnesium doped tin oxide (SnO2: Mg) thin film transistor are fabricated by ultrasonic spray pyrolysis deposition (USPD) successfully. We investigated including the advantage of USPD method to fabricate SnO2: Mg, the effect of doping magnesium and rapid thermal annealing at active layer. Finally, we have tried stacking oxide layers of TiO2 and Al2O3 to improve interface quality.
Three kinds of SnO2-based TFTs has been achieved in our work. The first structure consisted of Al2O3 oxide layer and SnO2 active layer exhibits performance with Ion/Ioff of ~108, subthreshold swing (S.S) of 203.5mV/dec, threshold voltage (Vth) of 1.20V, field effect mobility (μFE) of 82.8 cm2/V-s, and Vth shift of -1.00V under negative bias illumination stress (NBIS). The second structure consisted of Al2O3 oxide layer and SnO2: Mg active layer exhibits performance with Ion/Ioff of ~109, S.S of 173.3mV/dec, Vth of 1.15V, μFE of 95.7cm2/V-s, and Vth shift of -0.45V under NBIS. The third structure consisted of TiO2/ Al2O3 stacked oxide layer and SnO2: Mg active layer exhibits performance with Ion/Ioff of ~108, S.S. of 167.5mV/dec, Vth of 0.20V, μFE of 130.0cm2/V-s, and Vth shift of -0.40V under NBIS.
Higher μFE, smaller S.S. and Vth shift under NBIS produced after doping magnesium. It is attributed that magnesium can increase oxygen storage capacity. The defects between the interface of oxide layer and active layer are reduced, which contributes to the transmission of high-concentration carriers effectively, thereby improving the film properties.
Furthermore, stacking of the TiO2 reveals a further improvement in DC properties due to its effective limitation of amorphous Al2O3 grain size. The difference from the grain sizes of crystalline active layer and amorphous oxide layer become smaller, and the interface quality is improved effectively.
In our work, we successfully fabricated the superior performance SnO2: Mg TFTs by USPD method. The films deposited by this method is highly competitive in the market because of its low fabricate cost and non-vacuum environment. In Addition, the SnO2: Mg TFTs is a promising material with high electron mobility, normal-off operation, high Ion/Ioff and high reliability, which has great potential in the next generation of large-area panel industry applications. It is expected to be applied in the future market.

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