This thesis details the significant progress made in improving the performance of organic
transistors and the network conductivity of carbon nanotubes. The first section investigates
organic semiconductor nucleation and growth on the most common dielectric surface used to
fabricate organic thin film transistors. The nucleation and growth of the semiconductor was
determined to be a critical factor affecting the device performance. Excellent dielectric
modification layers which promote desirable semiconductor growth leading to high conductivity
were identified and a technologically relevant deposition technique was developed to fabricate
high quality dielectric modification layers over large areas. This may represent an important
step towards the realization of large area organic circuity. In the final section lessons
learned from studying organic semiconductor nucleation and growth were utilized to improve the
conductivity of carbon nanotube networks. Selective nucleation of materials at the junctions
between nanotubes in the network significantly decreased the network's sheet resistance. The
resulting networks may be promising candidates for transparent electrodes with a variety of
optoelectronic applications.
