Solution-phase deposition of oligomeric TFT semiconductors

Until now, most organic-based FETs have been fabricated by subliming the ac tive films onto device substrates at high vacuum, whereby useful orientatio nal order and intergrain connectivity are obtained For lower-cost devices, a major challenge is to duplicate this performance in semiconductors deposi ted from solution. We have prepared several thiophene-based compounds, both oligomers and thienoaromatics, that display high mobilities, in some cases equivalent to vacuum-deposited films, when cast from common solvents. The similarities between liquid- and vapor-phase processed films suggest that o ligomer solutions may be valuable for the production of all-organic electro nic circuitry.