SCANNING TUNNELING MICROSCOPY OF SURFACE MICROSTRUCTURE ON ROUGH SURFACES

An important feature of the scanning tunneling microscope (STM) is its ability to image nonperiodic or disordered surfaces with atomic or near-atomic lateral and vertical resolution. Many physical and chemical properties of surfaces and interfaces are sensitive to, and in some cases determined by, random roughness or surface disorder, although our understanding is hampered by the lack of suitable techniques for investigating atomic-scale features. We present STM results for microcrystalline Ag and nanocrystalline silicon surfaces which demonstrate the unique topographic data obtainable using the STM. For comparison, the STM studies are complemented by data obtained using conventional techniques. The ability of the STM to investigate the influence of growth conditions on surface morphology, such as ion bombardment, adsorption, and condensation temperature, is discussed.