本文利用射頻磁控濺鍍法沉積非晶型氧化鋅鈦銦薄膜，並討論在不同製程條件下薄膜的特性，接著將這些薄膜作為主動層應用於薄膜電晶體與紫外光檢測器，並進行分析及討論其特性。
首先以磁控濺鍍的方式在不同氧流量的製程條件下沉積薄膜，並且從三方向去討論氧化鋅鈦銦薄膜特性，分別是薄膜結構特性、薄膜光學特性及薄膜表面/縱深分析。在結構特性上，氧化鋅鈦銦薄膜使用磁控濺鍍的方式長得非常緻密且呈現非晶型態。而在光學特性的部分，實驗顯示薄膜在可見光區有80%的穿透率，可知氧化鋅鈦銦薄膜是一種寬能隙且高穿透的材料。此外，在薄膜表面/縱深分析結果中得知，因製作時氧流量的改變可以有效地改變材料氧空缺組成的比例，從X射線光電子能譜（XPS）圖得知，當氧流量越大時，薄膜裡的氧空缺會減少。
實驗的第二部分是將氧化鋅鈦銦應用於光檢測器，改變濺鍍通氧流量，以比較其特性差異。當氧流量提高時，能有效的抑制暗電流。在氧氣流量比例為4%的情況下，元件的暗電流為2.21 × 10−10安培，亮暗電流比為1.29 × 104，響應拒斥比為4.34 × 103。
實驗的第三部分是使用二氧化矽做為氧化鋅鈦銦薄膜電晶體的閘極介電層，並且藉由濺鍍通氧流量的改變，來找出薄膜電晶體最佳參數。在室溫下得到場效電子遷移率為0.884 cm2/V∙s，臨界電壓為−0.9 V，次臨界擺幅為0.41 V/dec，ON/OFF電流比為105。此外，本文也使用高介電常數的氧化鋁取代二氧化矽做為閘極介電層，提升的場效電子遷移率為2.317 cm2/V∙s，臨界電壓為1.39 V，次臨界擺幅改善至0.3 V/dec，ON/OFF電流比增加至106。最後，將薄膜電晶體延伸應用為光電晶體，在無偏壓的情況下可得到響應拒斥比為1817。

In this thesis, indium titanium zinc oxide (InTiZnO) is deposited by RF magnetron sputtering and the film properties are discussed thoroughly under different processing ambiences. Next, we will use InTiZnO thin film for device fabrication, including photodetectors and thin film transistors (TFTs).
In the first part of the experimental results and features discussion, we utilize the RF-sputtering system to grow films with different conditions and the film properties are discussed for three aspects which are structural, optical, and surface/depth element analysis. Thin films are amorphous grown by RF magnetron sputtering. And the measurement results show that the transmittance in the visible region can achieve more than 80%. Next, with the material element analysis, under the different sputtering oxygen flow ratios, films may exhibit different characteristics. The XPS results suggest that as the oxygen flow ratio increases, oxygen defects will decrease.
In the second part of the experiment, InTiZnO photodetectors are fabricated under various oxygen flow ratios to investigate differences among these devices. When oxygen flow ratio increases, InTiZnO photodetector can more effectively suppress dark current and the order of magnitude of current reach picoampere level, increasing the on-off ratio of devices. It is found that 4% oxygen flow ratio (Sample B) has the best performance compared to others. And with the optimized fabrication parameters, the dark current is 2.21 × 10−10 A, on-off ratio is 1.29 × 104, and the rejection ratio can reach 4.34 × 103.
In the third part, InTiZnO TFTs with silica (SiO2) as the gate dielectric layer are realized. Manipulation of oxygen flow ratios is conducted to find the optimized TFTs. The transfer characteristics of optimized TFTs at room temperature show the field effect mobility of 0.884 cm2/V∙s, threshold voltage of −0.9 V, and subthreshold swing of 0.41 V/dec. The on-off current ratio increased by approximately five orders of magnitude. In addition, we substitute alumina (Al2O3) for silica as the gate dielectric material via atomic layer deposition method. The devices show the field effect mobility of 2.317 cm2/V∙s, threshold voltage of 1.39 V, and subthreshold swing of 0.3 V/dec. The on-off current ratio increased by nearly six orders of magnitude. Lastly, InTiZnO TFTs are operated under light illumination to examine the performance. At no bias, we can obtain a rejection ratio about 1817.

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