Structure and morphology optimization of poly(3-hexylthiophene) thin films onto silanized silicon oxide

The influence of the preparation conditions, including substrate functionalization with common silanizers, onto structure/morphology of the overlying poly(3-hexylthiophene) thin films has been investigated by using both grazing incidence X-ray diffraction and atomic force microscopy. The factors determining the formation of spin-coated films suitable for applications in field effect transistors, i.e. concentration, spin-speed, and thermal treatment are addressed. We have established, by a tuning of the preparation and postdeposition treatments, the optimal conditions to get films with the required structural/ morphologic features. Moreover we have shown that the macromolecules orient and organize at the interface zone (610 nm from the interface) better than in the upper layers, i.e. far away from the interface.