本篇實驗是利用超音波噴塗熱裂解沉積法製備出雙主動層的氧化鋅錫以及二氧化錫摻鍶之薄膜電晶體。本論文的雙主動層薄膜電晶體在最好的厚度分配下，元件的線性區開關比可以達到~107、次臨界擺幅108.70 mV/dec、場效電子遷移率124.82 cm2/V-s、臨界電壓0.66 V以及3000秒的閘極負偏壓照光測試下的臨界電壓偏移為-0.16 V。
本實驗利用雙主動層的結構，不同厚度的氧化鋅錫與二氧化錫摻鍶薄膜，以及藉由快速熱退火和循環噴退的方式來提升元件的電性。此雙主動層的薄膜電晶體為下閘極的結構，我們利用氧化鋅錫作為下層的主動層，並當作主要傳輸載子的區域；上層的主動層為二氧化錫摻鍶，二氧化錫本身載子濃度很高，而鍶與氧的鍵結能力比錫與氧的鍵結能力強，因此我們藉由添加適當比例的鍶可以使二氧化錫中的氧空缺減少，使元件操作在關的時候通道更容易空乏，讓元件的操作為常關型的薄膜電晶體。
在本實驗當中，我們成功以超音波噴塗熱裂解沉積法製備出氧化鋅錫及二氧化錫摻鍶之薄膜電晶體，如此的薄膜沉積方式可以在非真空的環境下進行，並節省實驗成本與時間。此元件在電性方面表現出高電子遷移率、高開開關比、低次臨界擺幅等優點，且本研究中採用的主動層材料皆不含銦的成分，並用錫取代銦可以一樣讓載子達到快速傳輸的角色，目的是希望此薄膜能和氧化銦鎵鋅一樣有高遷移率，並改善使用銦會使成本提高的缺點，讓此結構的薄膜電晶體能夠在下一世代的大面積顯示器產業中極具潛力。

In this experiment, zinc tin oxide (ZTO) and strontium-doped tin oxide (SnO2:Sr) thin film transistors (TFTs) were fabricated by Ultrasonic Spray Pyrolysis Deposition (USPD) method. The TFTs with double active layers achieve an on/off ratio ~107 in linear region, subthreshold swing (S.S.) of 108.70 mV/dec, a field-effect electron mobility (μFE) of 124.82 cm2/V-s, a threshold voltage (Vth) of 0.66 V, and threshold voltage shift under the 3000-second gate negative bias illumination stress (NBIS) is -0.16V. These results were obtained using the optimal thickness distribution of the components.
In this experiment, we utilized a double active layer structure with different thicknesses of zinc tin oxide and strontium doped tin oxide films, rapid thermal annealing and multiple deposition / annealing method to enhance the electrical properties of the device. This double active layer thin film transistor was designed with a bottom gate structure. We utilized zinc tin oxide as the bottom active layer and as the primary carrier transport region. The top active layer was strontium-doped tin oxide, which has a high concentration of carriers. Since strontium has a stronger binding energy with oxygen than tin, we can reduce the number of oxygen vacancies in tin oxide by adding the appropriate amount of strontium. This makes the channel more susceptible to depletion when the device is turned off, enabling it to operate as a normally-off thin film transistor.
In this study, we successfully prepared zinc tin oxide and strontium-doped tin oxide thin films by ultrasonic spray pyrolysis deposition method. This method of thin film deposition can be carried out in a non-vacuum environment, which can save on experimental costs and time. This device exhibits high electron mobility, a high on/off ratio, and low subthreshold swing in electrical performance. Furthermore, the active layer materials utilized in this study do not contain indium. Substituting tin for indium can facilitate rapid carrier transport. The goal is to achieve high mobility comparable to that of indium gallium zinc oxide (IGZO) while addressing the issue of rising costs associated with the use of indium. The structure of thin film transistors has great potential in the next-generation large-area display industry.

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