ELECTROCHEMICAL SCANNING-TUNNELING-MICROSCOPY AND ATOMIC-FORCE MICROSCOPY OBSERVATIONS ON SI(111) IN SEVERAL SOLUTIONS

Electrochemical scanning tunneling microscopy (ESTM) and atomic force microscopy (AFM) images of hydrogen-terminated Si(111) in several solu tions have been studied tt, evaluate the performance of the AFM method . In dilute H2SO4 solution, the overall features of AFM images were si milar to those of ESTM images, suggesting that both images reflect the topography of the bare H-Si(111) surface. However, AFM images in ultr apure water and in dilute NaOH solution were successfully obtained, wh ile ESTM images were not. These results indicate that AFM is a powerfu l method for studying topographic change of Si in solutions during the wet cleaning process.