以塑膠基板搭配有機介電層製作而成的可撓式有機薄膜電晶體在商業應用上具有非常好的前景，塑膠基板提供有機薄膜電晶體可撓性，而以旋轉塗佈法製作出的有機絕緣層則使得基板可在低溫環境下製作。

在本研究中我們首先建立可撓式有機薄膜電晶體的標準製法，並且以所製作出的元件進行不同撓曲方向的持續時間撓曲實驗，以及不同撓曲方向搭配不同撓曲曲率半徑的撓曲次數實驗。不同撓曲方向的持續時間撓曲實驗對應到有機產品的收納，而不同方向搭配不同撓曲半徑的撓曲次數實驗則對應到有機產品的使用。

實驗中，我們以光學顯微鏡、原子力顯微鏡、以及雙聚焦離子束與電子束顯微鏡分析撓曲後元件的表面以及剖面狀態，並且搭配轉移以及輸出特性曲線分析元件的劣化情況。

研究結果顯示，撓曲方向垂直於通道對於有機薄膜電晶體的影響遠大於撓曲方向水平於通道，這是因為撓曲所產生主動層的龜裂影響了電流傳輸，而撓曲應力使得有機介電層薄膜與閘極的剝離則直接影響了元件的臨界電壓與開關電流比。

Compared with conventional organic thin-film transistors(OTFTs), the fabrication of flexible OTFTs replace silicon substrate with plastic substrate, and replace inorganic insulator with organic insulator, which make flexible OTFTs have flexibility and allow low temperature fabrication, these two characteristics let flexible OTFTs have the prospect in commercial application.

In our study, we establish stander process flows for the fabrication of flexible OTFTs, and then we bend our flexible OTFTs in different orientation for time dependent bending stress and bending stress in different bending radius. The time dependent bending stress simulate the condition of flexible OTFT products while storaging, and the bending stress in different bending radius simulate the condition of flexible OTFT while using.

We use optical microscopy (OM), atomic force microscopy (AFM) and dual-beam focused ion beam/scanning electron microscopy (FIB/SEM) to observe the top view and the cross section status of flexible OTFTs after bending, we also measure the output and transfer characteristics of flexible OTFTs to find out the reason of OTFTs electronic characteristic degradation after bending.

The experiment result indicates thatthe bending stress whose bending-orientation is perpendicular to the channel causes much damage to the active layer than the bending stress whose bending-orientation is parallel to the channel. Because cracks on active layer are perpendicular to drain current which limit the current while operating, and peeling between insulator and gate electrode will directly affect the value of on/off current ratio and threshold voltage.

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