Resumen de Preparation of Chemically Etched Tips for Ambient Instructional Scanning Tunneling Microscopy
Margot J. Zaccardi, Kurt Winkelmann, Joel A. Olson
A first-year laboratory experiment that utilizes concepts of electrochemical tip etching for scanning tunneling microscopy (STM) is described. This experiment can be used in conjunction with any STM experiment. Students electrochemically etch gold STM tips using a time-efficient method, which can then be used in an instructional grade STM that operates under ambient conditions. Electrochemical etching is one method used by researchers to prepare tips for high-quality STM imaging. Whereas the most common materials used to fabricate electrochemically etched tips cannot be used in ambient STMs, this experiment is a way to integrate the importance of tip etching (as opposed to mechanically prepared tips) into an STM laboratory experiment. The students are able to make Au tips with a reasonably small radius of curvature (<100 nm). First-year undergraduate students with almost no previous experience using an STM instrument were routinely able to achieve atomic resolution on a graphite surface.
