表面能調整於定義有機薄膜電晶體主動區之應用

Abstract

在此論文中，我們藉由表面能調整，已成功定義出五環素有機薄膜電晶體(pentacene based-OTFTs)的主動區域。首先，利用自組裝單層膜(SAM)來作介電層的表面處理，並透過石英光罩照射UV光等方法，來加以控制所需區域的表面能。接著，在處理過的介電層表面沉積上pentacene薄膜後，只需經由簡易的去離子水浸洗過程，便能將照射過UV光部分的pentacene薄膜移除，而獲得所要的主動層區域。另外，藉由吸附能與侵入能的分析，我們可知此方法為一剝除機制，而介於pentacene薄膜、基板與去離子水間的不同侵入能，便是成功定義出主動區的關鍵因素。而我們所提出的此定義方式，亦可與傳統的黃光微影製程結合，製作出OTFTs陣列。 接著，我們將浸洗後獲得的pentacene區域製作成元件來驗證此方法的可行性。藉由元件特性的分析，我們觀察到其可靠度等特性依然優於傳統結構的對照元件，載子移動率、電流開/關比值以及次臨界擺幅等特性皆有明顯的改善。

In this thesis, the pentacene patterning by adjusting the surface energy was discussed. Firstly the surface energy was controlled by the self-assembled layer (SAM) treatment and the partial ultra-violet (UV) light exposure through quartz-glass mask. Then, after pentacene deposition, water dipping was used to remove the pentacene on UV-exposed area. The adhesion energy and the intrusion energy were analyzed to reveal that the dipping was a lift-off process and the key for successful patterning was the intrusion energy between pentacene, substrate (hydrophilic or hydrophobic) and the D.I. water. The proposed technology was compatible to conventional lithography system and is applicable to OTFT arrays. Next, the remaining pentacene film was fabricated as a top-contact OTFTs to confirm the practicability of this technology. According to the output characteristics of OTFTs , the performance kept favorable and superior to that of the control sample. The mobility, the on/off current ratio (higher than 106) and the sub-threshold swing were also improved.