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A series of benzo[d,d]thieno[3,2-b;4,5-b]dithiophene (BTDT) derivatives, end-functionalized with phenyl (PBTDT), benzothiophenyl (BT-BTDT) were synthesized and characterized. A facile, one-pot synthesis of BTDT was developed which enables the efficient realization of a new BTDT-based semiconductor series for organic thin-film transistors (OTFTs). The crystal structure of P-BTDT was determined via single-crystal X-ray diffraction. Various combinations of surface treatment methods, substrate temperature, and deposition flux rate sequences have significant effects on device performance. Films deposited on octadecyltrichlorosilane (OTS)- treated SiO 2 substrates under properly adjusted substrate temperature and deposition flux rate achieve an efficaceous compromise between high film crystallinity and good film grain interconnectivity, resulting in good OTFT performance, with mobility greater than 0.70 cm 2 V -1 s -1 and I on /I off greater than 10 8 .

Mono-chrome phosphorescence Organic light emitting diodes (OLEDs) operated by organic thin-film transistors (OTFTs) with a 32×32 array are fabricated with a novel method, and the results reveal a fabulous demonstration. The later isolation, which segregated source/drain electrodes and an OLED cathode, was designed in our OTFT-OLED pixel. In the OTFT-OLED process; we used the polymer isolating layer which was deposited by spin coating and patterned by traditional photo-lithography before the organic semiconductor and OLED deposition. However, the residue polymer affect of OTFT electric properties which have poor mobility (5×10-4 cm2/V-s), a lower on/off ratio (~103), and a positive threshold voltage (4.5 V), and devices, have poor uniformity. Using UV-Ozone treatment could enhance OTFT mobility (2×10-2 cm2/V-s) and permit higher devices uniformity, but the threshold voltage would still have a positive 5.1 V. This threshold voltage was not a good operation mode for display application because this operation voltage was not fit for our driving systems. In order to overcome this problem, a new structure of OTFT-OLED pixel was designed and combined with a new-material isolating layer process. This new process could fabricate an OTFT-OLED array successfully and have a nice uniformity. After the isolating layer process, OTFT devices have a higher mobility (0.1×10-2 cm2/V-s), a higher on-off ratio (~107) a lower threshold voltage (-9.7 V), and a higher devices uniformity.