有鑑於社會對於能源議題非常重視，因此高效率低能耗元件更是不可或缺，為了實現高效率的能源輸出，半導體產業開始投入提高效能產品、降低功率能耗及節省材料使用等技術。因此本研究利用溶液製程高介電常數TiOx/SiOx有機混成(hTSO)之介電層結合聯噻吩(bithiophene)為核心及接上十四個碳之側鏈長度的硫碳鏈(thio-alkyl)取代基(SBT)，並以頭尾接上雙噻吩並噻吩基團(dithienothiophen-2-yl; DTT)的新型有機小分子半導體DDTT-SBT-14製備低電壓有機場效應光電晶體。DDTT-SBT-14之最大吸收峰為405 nm，因此可選用相近波長之藍色發光二極體作為光源，所製備之有機場效應光電晶體其光響應達200 A W-1、光敏度高於4000，並可於極小電壓(-3 V)操作。又因SBT中心上分子內的硫⋯硫作用力會呈現高度平面性的結構，並以溶液法製備具有高度一致性晶體結構進而促進電荷傳遞，使得電洞遷移率達0.25 cm2 V-1s-1。本研究將為有機半導體之發展提供高品質的晶體結構以及低功耗之有機光電子元件。;Low voltage driven organic phototransistor are promising for photosensor and memory device application. In this work, single crystalline and ordered aligned arrays of solution-sheared DDTT-BST, which contains thio-alkyl substituted bithiophene (BST) with end-capped dithienothiophene (DTT) group, was used as organic semiconductors layers. High dielectric constant of 120 nm-thick hybrid titanium-silicon oxide (TiSiOx)/organic (hTSO) thin film was used as gate dielectric in low-voltage phototransistor. For the optimized condition upon irradiation of LED blue light with a wavelength of 410 nm, these p-type organic phototransistors exhibited a photoresponsivity of 200 A W-1 and maximum photosensitivity reaches 2000 within an operating voltage of -3 V. This study aims to aid the development of organic semiconductors with high quality crystalline structures combined with low power consumption for future optoelectronics applications.
