Polycrystalline tetrabenzoporphyrin organic field-effect transistors with nanostructured channels

Solution-processed organic thin-film field-effect transistors (OFETs) were fabricated using a precursor form of the organic semiconductor tetrabenzoporphyrin (TBP) deposited on a thermal silicon oxide gate insulator patterned with nanometer-scale trenches. Thermal conversion of the precursor film to TBP was enhanced by ordered TBP aggregation in the prepatterned trenches, demonstrating precise control and placement of long- and short-range ordering of the organic semiconductor. OFETs with channels parallel to trench direction growth were found to have field-effect mobility approaching one order of magnitude greater than transistors fabricated with the channel oriented perpendicular to dendrimer growth.