利用塑膠基板搭配有機主動層與介電層製作而成的可撓式有機薄膜電晶體，在未來電子科技產業有非常好的前景。而有機薄膜電晶體具備可撓性、低溫製程、低成本和可大面積製作等優勢，因此在電子產品應用上相當多元，舉凡電子紙顯示器、無線射頻標籤、智慧服飾和大面積感測器等。
在本研究中，主要以探討元件在彎曲狀態下電特性之變化。首先，我們先建立一個可撓式有機薄膜電晶體的標準製程。將元件分別製作於厚度125 μm和25 μm的Polyimide (PI)塑膠基板上，並觀察在此二厚度基板之元件，彎曲4 mm曲率半徑下電特性的變化。接著，比較元件在厚度25 μm的PI塑膠基板上，彎曲不同曲率半徑(4、3、2、和1 mm)並量測其電特性的均勻度。最後，將元件長時間彎曲於曲率半徑1 mm狀態下，比較真空環境與大氣下電特性之差異。
研究結果顯示，厚度較薄之基板，在彎曲相同曲率半徑下，元件電特性的表現較為優秀，亦可承受較小之彎曲半徑；而在不同環境長時間撓曲的狀態下，發現長時間的彎曲狀態下，對元件本身並不會造成明顯劣化；但當大氣中的水氧與彎曲應力交互作用時，則會加速劣化元件的電特性。

Organic semiconductors and polymer dielectrics with plastic substrate recently have been an emerging technology for flexible electronic devices, such as organic thin-film transistors (OTFT). Organic thin-film transistors have the advantages of mechanical properties, low temperature processing, low cost, and large area capability and so have various potential applications such as paper-like displays, radio frequency identification tags, e-textiles, and large area sensors.
In our study, we investigated the transistors’ behavior during bending states, and not just only before and after bending. First, we established a standard manufacturing process of organic thin-film transistors, and chose thickness 125 μm and 25 μm polyimide for our flexible devices’ substrate to examine the electrical characteristics during the same bending radius of 4 mm. Next, we compared the uniformity of characteristics for the devices fabricated on 25 μm polyimide substrate with several bending radii of 4, 3, 2, and 1 mm. Eventually, the devices have stored separately in different environments, vacuum and atmosphere, with a long-term bending state to observe the variations in performance.
The experiment results indicate that thinner substrate could perform more excellent characteristics of OTFT with the same bending radius than that of thicker one, and better durability for smaller bending radii. While the device was in a long-term bending state in the vacuum, the performance wouldn’t deteriorate with time; however, when the device was placed in the air, the mechanical bending would accelerate the degradation of the electrical characteristics.

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