SURFACE-ROUGHNESS OBSERVATION BY SCANNING-TUNNELING-MICROSCOPY USING A MONOLITHIC PARALLEL SPRING

A new scanning tunneling microscope (STM) and its application to surfa ce roughness observation are described. Precision two-dimensional posi tioning of our STM instrument was achieved with a two-dimensional para llel spring driven by two stacked piezoelectric actuators (PZT), so th at the mutual interference effect between x- and y-axis displacements is very small. The PZT for the z-axis displacement and control was mou nted on the monolithic parallel spring. Therefore, the mutual interfer ence effect of three-dimensional displacements is negligible. We have applied this STM to observation of surface roughness. A block gauge an d a gold thin film evaporated on glass plates are observed at the cons tant-current mode and the zero bias voltage.