The properties of MOS structures using conjugated polymers as the semiconductor

Data is presented from electrical measurements on MOS structures using the conjugated polymer regioregular poly-3-hexyl-thiophene (P3HT), a derivative of polythiophene. Improvement of the molecular mass and chain length is achieved using a process of fractionation. This is expected to produce an improvement in the electronic properties of the polymer. Comparison between fractionated and unfractionated P3HT on both MOS and TFT devices is presented. Metal contacts to P3HT are also studied with the formation of Schottky barriers readily observed. Current is found to fit standard theory and allows calculation of dopant levels and barrier heights all of which show good agreement with the ideal theory. (C) 2001 Elsevier Science B.V. All rights reserved.