Solving a Problem that Plagues Scanning Tunneling Microscopes

Researchers at the University of Texas at Dallas have solved a longstanding problem that has been plaguing the scanning tunneling microscope for more than 35 years: How to prevent the tip of a scanning tunneling microscope from crashing into the surface of a material during imaging or lithography. Scanning tunneling microscopes (STMs) operate in an ultra-high vacuum, bringing a fine-tipped probe with a single atom at its apex very close to the surface of a sample. When voltage is applied to the surface, electrons can jump, or tunnel, across the gap between the tip and sample.