A successive dry-wet process for fabricating conductive thin film of bis(ethylenedithio)tetrathiafulvalene salt

Conductive thin films of a bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) salt have been constructed by a successive dry-wet process, which is a com bination of the ultra-high vacuum (UHV) deposition of neutral BEDT-TTF mole cules and an electrochemical doping process that utilizes an aqueous soluti on of LiClO4 as the electrolyte. The optimal temperature of the BEDT-TTF de position source is 80 degreesC, which gives a uniform coverage of the subst rate without any decomposition. The doping starts at the electrode/film. in terface, proceeds outwards from the interface and is completed after 5-7 h between the electrode gaps. The change in the surface plasmon resonance spe ctroscopy (SPRS) curve upon doping is best fitted by varying the dielectric constant of the BEDT-TTF film while keeping the thickness of the film cons tant. The conductivity of the doped BEDT-TTF film along the film plane was in the range 10(-3)-10(-4) S cm(-1). (C) 2001 Elsevier Science B.V. All rig hts reserved.