本論文研究使用自行合成十三烷基駢苯衍生物N,N’-ditridecyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C13H27)作為半導體材料，使用indium tin oxide (ITO)玻璃基板及polyether sulfone (PES)軟性基板製作成有機薄膜電晶體元件，觀察元件在不同彎曲曲率下的電特性變化及其在光感應器的應用。
本研究分為兩部分，第一部分改變元件高分子絕緣層參數，以不同交聯聚4-乙基苯酚(Cross-Linked poly(4-vinylphenol), C-PVP)濃度及不同塗佈旋轉轉速觀察元件之電特性變化，其中以poly(4-vinylphenol) (PVP)及poly(melamine-co-formaldehude) (PMF)濃度為12:4 wt%之C-PVP以塗佈旋轉速度為初轉10 s 500 r.p.m.、末轉30s 3000 r.p.m.的參數最為適合作為元件之介電層。此外，為了進一步改善元件電特性，將氟化鋰成膜於半導體層及電極層之間作為修飾層，加入修飾層後不僅能夠提升元件開電流並降低關電流，使元件開關電流比值提高，且飽和電流與載子遷移率也有明顯提升的趨勢。本實驗另研究元件經由彎曲後的電特性變化，經由實驗發現有機薄膜電晶體經由向內壓縮後，半導體層內的分子與分子之間的距離變近使分子間作用力增加因而減少載子傳遞能量損耗，因此，向內壓縮曲率增加時元件飽和電流增加、臨界電壓愈小；相反地，有機薄膜電晶體經由向外伸展後，半導體層內的分子與分子之間的距離變遠使分子間作用力減少因而增加載子傳遞能量損耗，因此，向外壓縮曲率增加時元件飽和電流降低、臨界電壓愈大。由半導體層的光激螢光光譜可發現元件經由向內壓縮後有紅位移現象，向外伸展後有藍位移現象，由此結果可證明當半導體層向內彎曲時，分子距離靠近，反之分子距離遠離。由半導體層的時間解析光激螢光分析可得向內壓縮載子生命期較長，向外伸展載子生命期較短，此結果與光激螢光光譜及元件彎曲量測結果一致。
第二部分將本研究第一部分的有機薄膜電晶體元件作光偵測器之應用並觀察元件在不同光照度及不同電壓下操作的結果，由於場效電流隨著操作電壓愈小而變小，因此操作電壓愈小時光電流貢獻愈大使光響應力大幅增加；本研究改變照光強度可發現隨著照光強度愈大、光電流愈明顯，由於照光使半導體層內載子激發產生電子電洞對，因此照光強度愈強愈能激發半導體層內的載子而產生愈多光電流。
本研究將薄膜電晶體製作在PES軟性基板上做光感應器之應用，實現在2.5V低電壓下可達到一百的光響應能力。

N,N’-ditridecyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C13H27) is synthesized and applied as the active layer in organic thin-film transistors (OTFTs) that were fabricated on indium tin oxide (ITO) glass substrates and polyether sulfone (PES) flexible substrates. The electrical properties of OTFTs and its application in photosensors were investigated under bending conditions.
This study is divided into two parts. In the first part, we demonstrated the different cross-linked poly(4-vinylphenol) (C-PVP) parameters, including concentration and thickness, spun on the insulator layers. The best results are achieved with C-PVP film with a weight concentration ratio of poly(4-vinylphenol) (PVP) to poly(melamine-co-formaldehude) (PMF) of 12:4 spun for 10 s at 500 rpm and then for 30 s at 3000 rpm. LiF is used as the buffer layer between semiconductor layers and electrode layers to improve electric performance. High on/off current ratios and saturation current, as well as excellent carrier mobility are obtained. As the flexible devices were compressed, the distance between PTCDI-C13H27 molecules was decreased to result in increase of the interaction force between molecules and decrease of the reorganization energy for carrier transportation. The saturation current gradually increased and the threshold voltage decreased with increasing substrate curvature. A photoluminescence analysis shows a slight red shift after device compression and a blue shift after device extension. Time-resolved photoluminescence analysis reveals that the compressed devices have a longer exciton lifetime.
In the second part, it was observed that the photoresponse significantly increased with decreasing applied voltage including gate and drain voltages. According to the lower effect field current under the lower operated voltage, the photocurrent became the dominate contribution. When n-type OTFTs were operated at a low voltage of 12 V, the photoresponse approaches 100 at 2.5 V for the flexible devices, making them suitable as photosensors.

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