本論文研究以聚(3,4-乙烯二氧噻吩):聚(苯乙烯磺酸) [poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)，PEDOT:PSS]作為有機薄膜電晶體源汲極的特性分析。製作以五苯環為半導體層之有機薄膜電晶體，使用PEDOT:PSS當頂部接觸式的源汲極，進行電特性研究，並與使用傳統金屬源汲極的元件進行比較；並對PEDOT:PSS薄膜和半導體層進行特性分析，包含片電阻、穿透光譜、原子力學顯微影像、掃描式開爾文探針顯微影、X射線光電子能譜、接面電阻等分析，並研究與元件電特性的關連性。在電特性分析上，以PEDOT:PSS為源汲極的元件表現稍低於以銀作為源汲極的元件；利用掃描式開爾文探針顯微影，分析源汲極和半導體層的表面電位，發現在源汲極和半導體層的表面電位差越小時，有較好的電特性表現，也發現將氧電漿處理於pentacene表面能下降與銀的表面電位差值；利用量測源汲極與半導體層之間的接面電阻，發現將氧電漿處理於pentacene表面能下降與銀的接面電阻；總結來說，成功將PEDOT:PSS製成有機薄膜電晶體的源汲極，並發現將氧電漿處理於pentacene表面對於電特性表現是有益的。

In this study, we investigated the effects of electrodes and post-treatment of active layers on the electrical properties of organic thin-film transistors (OTFTs). We fabricated pentacene-based OTFTs using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as the top contact source/drain (S/D) electrodes and compared the resulting electrical characteristics with those obtained using traditional Ag metal S/D electrodes. We also studied the contact resistance and electrical characteristics of the corresponding OTFTs. The electrical characteristics of OTFTs bearing PEDOT:PSS S/D electrodes were nearly similar to those of devices using Ag S/D electrodes. The surface potentials of the active layers and S/D electrodes were characterized by scanning Kelvin probe microscopy, and results revealed that smaller surface potential differences between the S/D electrodes and active layer yield smaller contact resistances and better electrical characteristics. In summary, we successfully prepared OTFTs utilizing PEDOT:PSS thin films as S/D electrodes and showing good electrical characteristics.

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