Abstract: This paper covers the electropolymerized polypyrrole doped with p-toluenesul-fonate studied using scanning tunneling microscope.The growth processes of polypyrrole films on the electrode surface were observed.Polypyrrole chain struc-ture with many separated micro-holes of 0.15 nm diameter at the initial state ofelectropolymerization can be seen from obtained STM images.This structure is ex-tremely similar to the pioneer-proposed ideal structure of polypyrrole chains.Thereexisted some helical structure and simple strands on the electrode surface, which isdue to different existing states of polypyrrole chains on electrode surface.STM ex-periments showed that polypyrrole chains were firstly formed on the electrode sur-face, then, they growed gradually by 3-dimensional mode during slow oxidation toform many separated micro-islands.Finally, a large corrugation area of polymerfilms occurred on the electrodes.

Key words: Electrochemical scanning tunneling microscopy, Polypyrrole films, Electrochemistry