有文獻指出，應用超薄的氟化鋰薄膜在有機電激發光二極體之中可以大幅度的改善載子注入的效率。在此論文中，我們引用了此種觀點在五環素薄膜電晶體的主動層與源極/汲極電極之間，期待因為氟化鋰緩衝層的加入可以大幅度的增進電洞注入主動層的效率。
我們使用不同的金屬金(Au)、鉑(Pt)或是鈀(Pd)來當源極/汲極，並嘗試著改變氟化鋰薄膜厚度去得到最佳厚度。由實驗結果發現，不論是何種金屬當源極/汲極，隨著不同的氟化鋰薄膜厚度改變，電晶體的電性表現都會有相對應的改善。當氟化鋰薄膜最佳化厚度為1奈米時，發現其飽和電流和電流開關比等電晶體特性能夠有最明顯程度的改善；此改善的原因可由文獻中推測，因為氟化鋰的加入可以使得載子注入主動層的能障降低，因而造成電晶體電流及載子遷移率的明顯提升。

Lithium fluoride (LiF) thin films have been previously used in organic light-emitting diodes to improve the efficiency of the carrier injection. Based on the concept, it is expected that inserting the LiF buffer layer between the active layer and the source/drain electrode could improve the electrical property of the pentacene-based thin film transistor due to the enhancement of the carrier injection from the source/drain electrode to the active layer.
Au, Pt, and Pd were employed as the source/drain electrodes, and then varied the thickness of LiF to obtain the optimum thickness of the buffer layer. Regardless of the type of metal used for the source/drain electrode, the experimental results showed that the performance of the transistors could be improved significantly by inserting the LiF thin film. The performance of the transistors in terms of the saturation current and on/off current ratio was optimized when the thickness of the LiF buffer layer was at 1.0 nm. This could be attributed to the decreased injection barrier between the source/drain electrode and the active layer, further improving the device performance, including saturation current level and mobility.

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