SHEARING STRESS ON THE SURFACE-TOPOGRAPHY BY SCANNING SHEARING STRESSMICROSCOPY

A scanning shearing stress microscopy has been developed in order to i nvestigate shearing stress effect in the surface. This microscopy is b ased on scanning tunneling microscopy and makes it possible to measure shearing stress. The sample is coupled on the AT-cut quartz resonator which is oscillated at its resonance frequency, and the shift of the resonant frequency corresponding to the strength of the shearing stres s in the sample can be measured. Gold thin films have been observed fo r the surface topography as the image of scanning tunneling microscopy and also the distribution of subsurface shearing stress is identified , simultaneously. The strong shearing stresses are generated at the ho llow parts of the surface topography. These stresses are caused by the frictional force between the scanning tunneling microscope tip and th e sample surface which is oscillated laterally. (C) 1996 American Vacu um Society.