We have investigated the effect of surface order on the orientation and mob
ility of pentacene. The surface order was created using monolayers and poly
mers that are normally used to align liquid crystals. Rubbed polyvinylalcoh
ol layers were found to align approximately 27% of the pentacene grains wit
hin a 30 degrees range. When introduced in a thin-film transistor, they wer
e found to enhance the saturation current by a factor of 2.5. A mechanism f
or this enhancement is proposed. (C) 2001 American Institute of Physics.