Measuring surface roughness of an optical thin film with scanning tunneling microscopes

Surface roughness of a fine metallic film. i.e.. mirror finished. has been determined by a Scanning Tunneling Microscope (STM). The mean value o the roughness is measured based on STM images of a three dimensional line plot of the surface profile. The technique is found capable of determining the roughness in a nanoscopic scale, lO m. Such technique is used in the present work to measure the roughness of various thin films ( 1 5 tm) in amorphous and crystalline structures.