Photocurrent spectroscopy allows to obtain spectra of ultrathin conduc
tive polymer deposits on electrode surfaces and to study the first ste
ps of anodic electropolymerisation. With poly(3-methylthiophene), elec
tropolymerisation takes place by deposition of solution formed oligome
rs but the results for poly(N-methylpyrrole) show gradual increase in
conjugation length.