具氯取代基之苝苯亞醯胺衍生物微米帶電晶體

Abstract

本論文探討具氯取代基之苝苯亞醯胺衍生物N,N′-bis[2-(4-chlorophenyl)ethyl]-3,4,9,10-perylenetetradicarboximide (Cl-PEPTC)，以溶液式製程成長為單晶微米帶，並製作為N型有機場效電晶體，其載子遷移率為1.05 × 10-3 cm2V-1s-1，臨界電壓為68.3 V，開關電流比為4.74 × 104。進而探討元件在不同環境下的電性穩定度，包含(ⅰ)氮氣手套箱、(ⅱ)一般大氣環境下(相對濕度為50 – 60 %)，及(ⅲ)高濕度環境(相對濕度 > 90 %)，其中在氮氣手套箱與一般大氣環境下，元件在第80天還有穩定的場效電性表現，其開關電流比仍維持在103，造成元件電性下降的主要原因，可能為氫氧根基團形成陷井而捕捉載子。 為探討Cl-PEPTC微米帶場效電晶體的相關應用，選用三種LED－白、紅及綠光源照射元件，進行光電晶體特性量測，其中在白光的照射下，可得到最高載子遷移率的提升。透過三種不同功率密度的光源，可知光電流與暗電流比(photocurrent/dark-current)受到功率密度大小影響，光響應度(photoresponsivity)則受到Cl-PEPTC微米帶吸收光譜的影響。最後，將Cl-PEPTC微米帶場效電晶體進行變溫量測，結果顯示載子遷移率隨著溫度上升而提高。

This study employed a chloro-substituted perylene diimides derivative (Cl-PEPTC) for the formation of self-assembled single crystal micoribbons by solvent exchange method. Transistor devices based on a network of Cl-PEPTC microribbions have showed typical n-channel field-effect behaviors. The extracted maxima mobility was 1.05 × 10-3 cm2V-1s-1, threshold voltage was 68.3 V and on/off current ratio was 4.74 × 104. The devices were further measured under three different conditions: (ⅰ) glove box, (ⅱ) ambient air (relative humidity 50 – 60 %) and (ⅲ) high humidity environment (relative humidity > 90 %). After 80 days, the transistor showed a remarkable stability. The on/off current ratio still maintained in the order of 103. The reason of transistors degradation is probably due to that the hydroxyl group formed at the semiconductor/dielectric interface trapped and captured the electron carriers. In order to investigate the potential application of Cl-PEPTC field-effect transistor, three commercial white, red and green LEDs were employed for photo response behavior study. The highest mobility enhancement was observed under white light irradiation. It was found that the photocurrent/dark-current ratio was affected by the power density of light sources. The photoresponsivity was affected by the matching of the absorbance of Cl-PEPTC microribbons and the emitting spectrum of light sources. Finally, Cl-PEPTC field-effect transistor was measured under different temperature. It was found that the mobility was enhanced with increasing temperature.