MODIFICATION OF POLY(3-METHYLTHIOPHENE) (PMET) STRUCTURE DURING ELECTROCHEMICAL DOPING-UNDOPING, STUDIED BY IN-SITU ATOMIC-FORCE MICROSCOPY(ECAFM)

Doping and undoping of poly(3-methylthiophene) (PMeT) layers were perf ormed in an electrochemical atomic force microscopy (ECAFM) microcell, and images accounting for modification of the polymer surface were co ntinuously recorded. The main result is that the variation of polymer morphology is very slow in relation to the modification of doping char ge. The discrepancy between the two time constants, related respective ly with ion and solvent molecule transfer and by electronic charge tra nsfer, was emphasized by in situ ellipsometry. In this case the variat ion of optical properties against doping charge is very fast.