高效能透明有機薄膜電晶體

Abstract

本論文是利用一種新穎的電極結構來製作透明有機薄膜電晶體，由於indium-tin-oxide（ITO）電極和pentacene的介面能位障較高，因而影響載子注入造成元件特性不佳。經由金屬氧化物（MoO2或V2O5）的修飾，可以使得元件特性大幅的提升。利用這種新穎的電極結構，我們製作出在可見光波段穿透率達60%以上的元件。 此外，實驗發現大部分的吸收來自於半導體層，因此可藉由降低半導體層的厚度來增加元件穿透度，當pentacene厚度降到200Å時，發現元件特性並無變化太多，而元件穿透度已成功達到70%以上。可以預期的是這種透明有機薄膜電晶體將會非常適於用來驅動液晶顯示器。

One novel electrode-architecture has been adapted to fabricate transparent organic thin-film transistors (OTFTs). Due to the high injection barrier of the indium-tin-oxide (ITO)/pentacene interface, the device exhibited a non-ideal behavior. After the modification of the contact by inserting a thin-layer of one metal oxide (MoO2 or V2O5), the device performance was improved dramatically. By using the novel electrode architecture, an OTFT with more than 60 % transmittance in the visible region has been demonstrated. In addition, the transmittance was further improved by reducing the thickness of the semiconducting layer, which has been identified as the main component absorbing the visible light in the devices. Comparable device performance was still obtained, even though the thickness of pentacene was reduced to 200Å. As a result, one OTFT with over 70% transmittance has been demonstrated successfully. It is anticipated that the transparent OTFTs would be very suitable to be the driving circuits for liquid crystal displays (LCDs).