Response Towards Humidity of Air Stable FETs Based on Polyhexylthiophene Dispersed in Porous Titania

Titanium dioxide films deposited by spraying colloidal dispersions of TiO 2 nanocrystals prepared by laser ablation are characterized by means of Scanning Electron Microscopy (SEM). The metal oxide films are sprayed on the top of gold drain-source contacts thermally evaporated onto SiO 2 coated p-doped silicon wafers. Organic Field Effect Transistors (OFET) are developed by infiltrating polyhexylthiophene solutions into the TiO 2 film. It is found that the presence of the TiO 2 layer improves the air stability of polyheylthiophene OFETs, even in the presence of moisture. In addition, the porous titania layer has remarkable effects on the way the polyhexylthiophene OFETs respond to humidity