探讨其结晶方向对51双三乙基矽烷基乙炔基双噻吩蒽有机薄膜电.docx

1、探讨其结晶方向对51双三乙基矽烷基乙炔基双噻吩蒽有机薄膜电探討其結晶方向對5,11-雙(三乙基矽烷基乙炔基)雙噻吩蒽有機薄膜電晶體之特性Studies on the Electrical Characteristics of 5,11-Bis(triethylsilylethylnyl) anthradithiophene Organic Thin Film Transistors by Crystal-Grown Direction 專題生：江艾樺 ( Ai-hua Jiang )指導教授：郭欽湊（Prof. Chin-Tsou Kuo）大同大學化學工程學系專題報告Department of

2、 Chemical EngineeringTatung University中華民國一百零一年十一月Nov. 2012摘要本實驗以Triethylsilylethylnyl anthradithiophene (TES ADT)作為半導體層材料，並使用定量吸管拖曳液滴的方式塗佈半導體層，來探討拖曳方向對TES ADT跟元件電特性的影響。由實驗得知，將液滴直接滴落於通道中間時，所測得的載子位移率是為最佳的，其mobility值為1.4410-1 cm2/Vs，on/off current ratio為2.60 104，VT為-4.2 V。而有方向的形況，則是夾角為45度之元件電特性最差。目錄摘要

3、. I目錄. II圖目錄 IV表目錄. VII第1章 簡介. 11-1前言. 11-2能帶理論. 2第2章 文獻回顧. 42-1有機薄膜電晶體(Organic Thin Film Transistor，OTFT) 42-2 電晶體之重要參數及公式計算. 52-2-1 載子位移率(Mobility). 5 2-2-2 起始電壓(Threshold voltage, VT). 72-2-3 次臨界斜率(Subthreshold slope). 72-2-4 開關電流比 (On/off current ratio). 82-3 結晶型態的控制. 82-4 雙(三異丙基矽烷基乙炔基)雙噻吩蒽. 92-

4、5 研究目的及動機 11第3章 實驗. 123-1 器材. 12 3-2 步驟 133-2-1 OTFT元件之製備:下接觸式元件(Bottom-contact). 133-2-2 半導體成膜. 173-2-3 儀器原理及參數設定. 18第4章 結果與討論. 20第5章 結論. 36參考文獻. 37圖目錄Figure 1-1 Simple band picture explaining the difference among the (a) insulator, (b) semiconductor, and (c) metal 93Figure 2-1 Schematic representa

5、tions of field-effect transistor architectures, (a) top-gate bottom-contact, (b) top-gate top-contact, (c)bottom-gate bottom-contact, and (d) bottom-gate top-contact13 4Figure 2.2 Structure of TIPS-PEN (a) and TES-PEN (b). 9Figure 2.3 Structure of TES ADT 10Figure 3-1 Architecture of TES ADT OTFT: (

6、a) sidelong glance and (b) overlook. 16Figure 3-2 Fabrication process of TES ADT thin film deposited on the substrate. 17Figure 3-3 A plot of potential energy versus internuclear distance for the Interaction between two atoms. 19Figure 3-4 Schematic assembly of an AFM 19Figure 4-1 Optical microscopi

7、c images of TES ADT deposited with (a) the nucleus in channel and the crystal grew (b) perpendicular, (c) parallel, (d) diagonal to the current flow between source and drain electrodes 21Figure 4-2 (a) Output and (b) transfer characteristics of the TES ADT OTFT with the nucleation in the channel. 23

8、Figure 4-3 (a) 2D and (b) 3D atomic force micrograph images of the TES ADT thin film with the nucleation in the channel. 24Figure 4-4 (a) Output and (b) transfer characteristics of the TES ADT OTFT with the crystal grew perpendicular to the current flow between source and drain electrodes. 26Figure

9、4-5 (a) 2D and (b) 3D atomic force micrographs of the TES ADT thin film with the crystal grew perpendicular to the current flow between source and drain electrodes. 27Figure 4-6 (a) Output and (b) transfer characteristics of the TES ADT OTFT with the crystal grew parallel to the current flow between

10、 source and drain electrodes. 29Figure 4-7 (a) 2D and (b) 3D atomic force micrographs of the TES ADT thin film with the crystal grew parallel to the current flow between source and drain electrodes. 30Figure 4-8 (a) Output and (b) transfer characteristics of the TES ADT OTFT with the crystal grew di

11、agonal to the current flow between source and drain electrodes. 32Figure 4-9 (a) 2D and (b) 3D atomic force micrographs of the TES ADT thin film with the crystal grew diagonal to the current flow between source and drain electrodes. 33表目錄Table 4-1 Electrical parameters of TES ADT OTFT. 35第一章簡介1-1 前言

12、自從Bell實驗室的Bardeen與Brattain 1在1947年製造出世界第一個電晶體(transistor)以來，以無機半導體為材質如silicon (矽)與gallium arsenide(砷化鎵)之電晶體一向為半導體電子業的主流。然而無機材料始終有彎曲及高成本的缺點。因此軟性電子的概慢慢出現，即以具可撓曲性的有機材取代。由於有機物具有可撓曲性、製程溫低，低污染、輕薄等優點，可以進溶液製程可以進一步低成本。因此，雖然有機電晶體在電性表現上無法完全取代無機物，但價格上的優勢使其有新的應用域，如射頻標籤、電子條碼、可撓曲式顯示器、電子紙等，這些產品也帶動有機半導體的研究。有機導電性高分子可

13、取代傳統之無機半導體，其沉積程序較為簡易，並可進行大面積生產、低溫製程等特點，對於電晶體結構日趨複雜化的現在，無疑是一大突破。有機場效電晶體(organic field effect transistor； OFET)又可稱為有機薄膜電晶體(organic thin-film transistor； OTFT)，主要運作原與無機的氧半場效電晶體(MOSFET；metal oxide semiconductor field effect transistor)相似，差別在於將無機材以有機材替代。有機半導體大致可區分為鏈狀或網狀結構的高分子材料以及小分子；文獻中最早的有機固體可以導電的現象可追朔到1906年，科學家發現anthracene晶體的光電導特性2，並於1940年，有更多有機材料的研究3，共軛高分子的研究在1970年4才逐漸發展。共軛導電高分子主要的特徵在於高分子主鏈是由交替的單鍵-雙鍵共軛鍵結(conjugated bonding)而成，而有機半導體之所以能夠導電，主要是利用非定域化(delocalize)中混成軌域(hybride o