本論文以超音波噴塗熱裂解沉積法研製非晶型氧化鎵錫以及氧化鋁錫薄膜電晶體。本實驗主動層在最佳的比例下，氧化鎵錫的元件在線性區開關比可以達到~10^9、次臨界擺幅133.08mV/dec、場效電子遷移率33.79 cm^2/V-s、臨界電壓0.41V以及3000秒的閘極負偏壓照光測試下的臨界電壓偏移為-0.24V；氧化鋁錫的元件線性區開關比為~10^7、次臨界擺幅118.43mV/dec、場效電子遷移43.22 cm^2/V-s、臨界電壓1.24 V以及3000秒閘極負偏壓照光測試下的臨界電壓偏移為-0.23V。
本實驗透過摻入不同比例的鎵、鋁形成氧化鎵錫以及氧化鋁錫等三元化合物以提升閘極負偏壓照光穩定度以及其它電性。閘極負偏壓照光測試常常被用來作為薄膜電晶體的穩定度指標，造成閘極負偏壓照光穩定性變化的主要原因來自照光後產生的電洞被侷限在介電層或通道層與介電層間，以及主動層中的電中性氧空缺照光後產生的電子被侷限在通道表面。在本次實驗中，我們用閘極加偏壓-5伏特以及持續照光3000秒，在最佳電性的氧化鎵錫及氧化鋁錫元件上測得的偏移量分別為-0.24V及-0.23V，甚至在含有更高比例的鋁的氧化錫鋁元件上測得-0.12V的偏移量，這些優異的穩定度表現主要歸因於較寬的光學能隙可以減少照光時所產生的電子電洞對，以減少電洞被侷限在介電層及電子被侷限在通道的情形發生。此外，氧化鎵錫及氧化鋁錫都有著比二氧化錫較少的氧空缺，因此也有著較好的開關特性。
在本論文中，我們成功以超音波噴塗熱裂解沉積法製備非晶型氧化鎵錫及氧化鋁錫薄膜電晶體，此沉積薄膜方法在製程時間以及成本皆相當具有優勢。在元件電性表現方面擁有高穩定性、高電子遷移率、高開開關比等優點，且本研究中採用的非晶型結構，目的是希望薄膜能像氧化銦鎵鋅一樣有較好的均勻性，使其在下一世代大面積顯示器產業中極具潛力。

In this thesis, amorphous gallium tin oxide (GTO) and aluminum tin oxide (ATO) thin film transistors were fabricated by Ultrasonic Spray Pyrolysis Deposition (USPD) method successfully. In our works, under the optimal ratio of the active layer, the GTO device exhibited the on/off ratio of ~10^9 in the linear region, subthreshold swing (S.S.) of 133.08 mV/dec, the field-effect electron mobility (μFE) of 33.79 cm^2/Vs , the threshold voltage (Vth) of 0.41V and the threshold voltage shift under the 3000-second gate negative bias illumination stress (NBIS) is -0.24V; the ATO device exhibited the on/off ratio of ~10^7 in the linear region, subthreshold swing (S.S.) of 118.43 mV/dec, the field-effect electron mobility (μFE) of 43.22 cm^2/Vs , the threshold voltage (Vth) of 1.24 V and the Vth shift under the 3000-second NBIS is -0.16V.
In this experiment, ternary compounds such as gallium tin oxide and aluminum tin oxide are formed by doping different proportions of gallium and aluminum to improve the stability of the NBIS and others electrical characteristic. The gate negative bias illumination stress (NBIS) is often used as the stability index of TFT. The main reason for the change of NBIS comes from the fact that the holes generated after illumination are fixed in the dielectric layer or between the channel layer and the dielectric layer, and the electrons produced by the neutral oxygen vacancies in the active layer are fixed on the surface of the channel after illumination. In this experiment, we used gate bias voltage -5V and continuous illumination for 3000 seconds. The NBIS shift of optimal electrical characteristic GTO and ATO devices were -0.24V and -0.23V, respectively, and even on the ATO device containing a higher proportion of aluminum, the NBIS shift was -0.12V. These excellent stability performances are mainly attributed to the wide optical bandgap which can reduce the electron-hole pairs generated during illumination. In addition, GTO and ATO have fewer oxygen vacancies than SnO2, so they also have better switching characteristics.
In this study, we have successfully fabricated amorphous GTO and ATO TFTs by USPD method, which has considerable advantages in process time and cost. The devices we fabricated have the advantages of high stability, high electron mobility, and high on-off ratio. The amorphous structure used in this research aims to hope that the film can have a better uniformity like indium gallium zinc oxide. It has great potential in the next-generation large-area display industry, and it is also expected to be explored and applied in the future.

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