The characteristics of low-voltage n-channel organic thin-film transistors (TFTs) based on the small-molecule semiconductors N,N’-bis(2,2,3,3,4,4,4-fluorobutyl)-(1,7 & 1,6)-dicyano-perylene-tetracarboxylic diimide (ActivInk N1100) and 2,9-bis(heptafluoropropyl)-4,7,11,14-tetrabromo-1,3,8,10-tetraazaperopyrene (TAPP) are compared. Staggered and coplanar TFTs were fabricated, and all measurements were performed in ambient air. In the coplanar TFTs, the source and drain contacts were treated with one of three different thiols. Overall, the two semiconductors provide similar performance, with electron mobilities up to 0.15 cm2/Vs, on/off ratios up to five orders of magnitude, subthreshold slopes as small as 130 mV/decade and contact resistances (measured using the transmission line method) as small as 21 kOhm-cm.
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