本論文以超音波噴塗熱裂解法製備高效能氧化銦錫鋅薄膜電晶體，並且探討在不同推進氣體下，其主動層薄膜內氧空缺含量對薄膜電晶體之電性影響。以空氣和氮氣為例，轉換特性分別為開關電流比~10^5、次臨界擺幅290 mV/dec、臨界電壓 0.50 V 和飽和電子遷移率14.09 cm^2/V-s以及開關電流比~10^6、次臨界擺幅150 mV/dec、臨界電壓 0.69 V 和飽和電子遷移率26.04 cm^2/V-s，較高的開關電流比和飽和電子遷移率歸因於氧化銦錫鋅薄膜之中的氧空缺可以幫助電子傳遞，進而使薄膜導電性提升。
在薄膜電晶體穩定性之測試當中，正閘極偏壓照光測試與負閘極偏壓照光測試常常被用來作為穩定度的指標。由結果得知以空氣或氮氣製備之薄膜電晶體在正閘極照光偏壓測試擁有比較好的表現，而負閘極照光偏壓測試當中由於螢光燈包含能量大於氧化銦錫鋅能隙之近紫外光，會激發薄膜之中電中性氧空缺產生電子電洞對，進而影響薄膜電晶體穩定性使臨界電壓變小。因此，由氮氣成長之氧化銦錫鋅薄膜電晶體因其氧空缺含量較多也使其臨界電壓偏移量較大，其偏移量分別為-0.63 V 與 -1.01 V 。
本實驗成功以超音波噴塗熱裂解法製備高效能氧化銦錫鋅薄膜電晶體，所成長之高品質薄膜以低成本和非真空之優勢和傳統薄膜濺鍍法相較勁，而在元件電性方面 擁有高電子遷移率及高穩定性等優點，使之為下次世代面板產業應用中極具潛力之 材料，可望在未來取代市面上常用之氧化銦鎵鋅。

In our work, we deposit the Al2O3 dielectric layer and ITZO active layer for TFTs application by Ultrasonic Spray Pyrolysis Deposition (USPD), and investigated on the oxygen vacancies in the ITZO thin film for TFTs DC electric characteristic.
The TFT with air carrier gas fabricated exhibits performance with Ion/Ioff of ~10^5, subthreshold swing (S.S.) of 290 mV/dec, threshold voltage (Vth) of 0.50 V, and saturation mobility (μsat) of 14.09 cm^2/V-s, and the TFT with nitrogen gas fabricated exhibits superior performance with the Ion/Ioff of ~10^6, low S.S. of 150 mV/dec, Vth of 0.69 V, and high μsat of 26.04 cm^2/V-s. The higher mobility is due to the more oxygen vacancies in the nitrogen deposited ITZO thin film.
In the TFTs stability test, the positive bias illumination stress (PBIS) and negative bias illumination stress (NBIS) has been recognized as the significant index for metal oxide TFTs. The results indicated that the TFTs were more stable under PBIS. For NBIS, the photo energy of fluorescent lamp was larger than the band gap energy (Eg ~2.13 eV) of the ITZO, then the electron hole pairs will be created via a band-to-band transition from oxygen vacancy and caused the negative Vth shift. The negative Vth shift are -0.63 V and -1.01 V respectively, which suggested the more number of oxygen vacancies could result in instability.
In our work, we successfully fabricated the superior performance ITZO TFTs by Ultrasonic Spray Pyrolysis Deposition (USPD). The advantages of non-vacuumed and low cost make USPD competitive with conventional sputtering fabrication. Additionally, the ITZO TFTs is a promising material with high electron mobility and reliability make ITZO replace with IGZO for the next-generation displays applications.

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