本研究利用IGZO薄膜應用在PET塑膠基板，製作成可撓式薄膜電晶體的元件。藉由改善通道層之製程條件，並且測試蝕刻製程，對於薄膜電晶體的影響而得到較好的元件特性。最後，也測試了可撓性薄膜電晶體在經過彎曲狀態下之特性變化。研究中調整通道層沉積條件中氧氣部分，當成長環境的氧流量增加時，使薄膜內的氧缺位減少，進而可調整元件的起始電壓至0V。其次加入護佈層，提升元件特性，以沉積二氧化矽為護佈層時，其場效等效移動率、臨界電壓、Ion/Ioff及次臨界擺幅分別達24.61 cm2/V-s、1.6 V、107及0.25 V/decade。接下來提出之蝕刻製程，目的為改善薄膜間介面態品質，其確實可降低元件之次臨界斜率至0.17 V/decade，並以C-V量測佐證蝕刻製程可將元件介面態降低Nit=2.13×1011 eV-1cm-2。在可撓量測中，發現載子移動率在測試過程中皆為24 cm2/V-s左右，表示在彎曲半徑1.38cm時，此種程度彎曲測試對研究中的元件並無太大影響。在彎曲半徑1.17cm時，元件特性則因通道層受彎曲影響有所下降。

The IGZO thin film transistors (TFTs) were successfully fabricated on the plastic polyethylene terephthalate (PET) substrate using magnetron radio frequency (RF) co-sputtering system. By adjusting the channel layer depositing conditions and using wet-etching method, the device exhibited better performance. Finally, the bending test was used on the flexible thin film transistors to research the change of device characteristics.
The oxygen vacancy in IGZO channel layer was decreased by adjusting depositing oxygen flow rate, which can change device turn-on voltage to 0V. The device performance was enhanced by adding passivation layer. The electric properties, such as the field-effect carrier mobility, threshold voltage, on-to-off ratio, and subthreshold swing were improved to 24.61 cm2/V-s, 1.6 V, 107, and 0.25 V/decade, respectively. The wet-etching method was investigated to improve the quality of interface. The subthrehold swing was decreased to 0.17 V/decade and the C-V measurement was tested to show that the using of wet-etching method could decrease Nit to 2.13×1011 eV-1cm-2. In the bending test, the carrier mobility was almost 24 cm2/V-s. Under bending radius 1.38 cm, there are no significant changes in this device. However, the TFT device performance was affected due to bending radius decreased to 1.17 cm.

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