Growth kinetics of Fe films electrodeposited on n-Si(111)

Iron thin films were grown directly on n-Si(111) substrates by pulsed electrodeposition in a non-aqueous 0.1 M FeCl2 electrolyte solution. In this solution, Fe2+/Si interface showed a good diode behavior by forming a Schottky barrier. From single-step potential experiment in the potential ranges from 1.0 to 1.4, the formation of Fe nuclei in the early deposition stages was proceeded according to the three dimensional (3) instantaneous nucleation followed by diffusion-limited growth rather than a progressive one. When depositing Fe using pulse potentials with the maximum voltage of 1.0 and 1.5 V, it was found that nucleation mechanism of Fe is similar with the results for the case of single-step potential experiment. However, nucleation during depositing Fe at 2.0 V initiated according to the progressive mechanism. Fe thin films, which obtains from pulse potential of 1.4 V with a frequency of 300Hz, revealed a highly oriented columnar structures perpendicular to the surface of Si(111) and that only the single phase alpha-Fe(110) was grown oil Si(111) substrate.