All jet-printed polymer thin-film transistor active-matrix backplanes

Thin-film transistor (TFT) backplanes fabricated by using jet printing as the only patterning method are reported. Additive and subtractive printing processes are combined to make 128x128 pixel active matrix arrays with 340 mum pixel size. The semiconductor used, a regioregular polythiophene, poly[5,5'-bis(3-dodecyl-2-thienyl)-2,2'-bithiophene]; (PQT-12) is deposited by inkjet printing and exhibits average TFT mobility of 0.06 cm(2)/VS, on/off ratios of 10(6), and minimal bias stress. The printed TFTs have high yield with a narrow performance distribution. The pixel design benefits from the registration accuracy of jet printing and it is shown that the electrical performance is suitable for addressing capacitive media displays. (C) 2004 American Institute of Physics.