REAL-TIME INSITU STUDIES OF METAL ELECTRODEPOSITION WITH SCANNING TUNNELING MICROSCOPY

Scanning tunnelng microscopy was used to observe the deposition of silver from electrolytic solution under controlled-current electrochemical conditions onto a smooth graphite substrate. The silver was deposited at 20 µA cm-2 and the growth of the deposits which initially formed was monitored in situ with scanning tunneling microscope (STM) over a scan area of 460x460 nm. The deposits showed various two- and three-dimensional morphologies and growth rates after nucleation. The apparent diffusion of deposit during the STM scan may be ascribed to interactions between the deposit and the scanning tip. The influence of the tip must be carefully considered when interpreting the images, particularly with inhomogeneous systems where the binding strength between the materials being studied may be overcome by interactive forces between the tip and sample. © 1990, American Vacuum Society. All rights reserved.