以剝離法改善奈米壓印製程與有機垂直電晶體

The improvement of nanoimprint lithography by strip-off method for vertical organic transistor

林家合(Chia-Ho Lin)

指導教授 ： 洪勝富

國立清華大學/電機資訊學院/電子工程研究所/碩士(2014年)

摘要

隨著軟性電子元件的發展逐漸成熟，具有低成本、大面積與捲對捲量產等優點的液態製程有機電晶體其潛力可期。本論文主要在探討過去本實驗室所開發的有機垂直電晶體─空間電荷限制電晶體。過去本團隊雖然可以製作出同時具有高輸出電流、高開關電流比與低操作偏壓等良好特性的有機垂直電晶體，但元件電性常常受限於製程方式。我們利用非緊密排列的奈米球作為金屬基極蒸鍍遮罩，然而奈米球的的隨機排列容易出現因球聚集而產生孔洞過大的問題。過去的研究顯示，過大的電子傳輸通道將會產生較大的漏電流。奈米壓印技術具備了高穩定性與可大面積化製程的發展潛力。本研究與台灣大學王倫教授實驗室合作，一同開發規則金屬網基極。成功以奈米壓印製程製作出規則金屬網基極，但卻受限於鋁濕式蝕刻製程。濕式蝕刻在製作規則金屬網的同時，會對元件上造成有機材料的離子汙染，而產生漏電流。此研究中將濕式蝕刻從製程中去除，改以奈米壓印搭配掀離法來製作奈米金屬網，有了突破性的成果，成功將基極漏電流縮小近一個數量級，同時具備高穩定性與再現性，製作出元件具有開電流4.64 mA/cm2及開關電流比到105以上的元件特性。相信未來將奈米壓印製程導入可撓性基板上，更佳的元件特性將可以被預期。

關鍵字

奈米壓印 ； 空間電荷限制電晶體 ； 大面積 ； 掀離

並列摘要

By the help of blossom develop status of flexible eletronic devices, the solution-processed organic transistors now show its bigger application potential in low-cost roll-to-roll large-area mass produciton. This thesis mainly focus on space-charge-limited transistor (SCLT), a vertical organic transistor develpoed by our group. Though SCLT has good charateristics like high output current, high ON/OFF current ratio and relatively low operational voltage, but its performance is unstable due to the fabrication process. We use nano sphere as a evaporation mask. But accommodation effect may easily occur because of the random arrangement of sphere. It may produce larger hole, and causing larger leakage current. Nanoimprint lithography is promising at high yield and large-area fabrication potential. In this work, we cooperate with Dr. Lon A. Wang’s group to develop the well-regular-ordered metal mesh base-electrode. However, the performance of imprinted SCLT is limited by Al wet-etching process. The ion contamanation caused by wet-etching may induced leakage current. Lately we try to combine nanoimprint with lift-off method and successfully reduce the leakage current by a order. The ouput current of SCLT device reaches 4.64 mA/cm2 and the ON/OFF current ratio increases to more than 105. We believe that we can apply nanoimprint lithography on flexible substrate in the future. And better performance of SCLT would have be predicted.

並列關鍵字

Nanoimprint lithography ； SCLT ； large-area ； lift-off

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