ELECTROCHEMICAL SMOOTHING OF SILICON (111)

Photocurrent oscillations on n-type silicon (111) in acidic fluoride s olutions lead to a reduction of the microscopic roughness on these sur faces, as investigated by Fourier transform infrared spectroscopy (FTI R) with attenuated total reflection techniques under in situ condition s, and by scanning tunneling microscopy (STM) performed in air. Roughn ess parameters obtained by STM measurements were reduced from 40 +/- 8 to 7 +/- 1 angstrom. The spatial and temporal synchronization during photocurrent oscillations leads to smoothing of large surfaces with a better result than applying an electropolishing treatment.