The thinnest films of copper look flat, but they aren’t
Newfound nanolandscape of valleys and ridges may impact efficiency of electronics
Like the surface of an alien planet, thin sheets of copper display a complex topography of ridges and valleys. These never-before-seen undulations may spell trouble for electronic gadgets: The zigzagging surface could contribute to the electrical resistance of miniature copper wires that snake throughout computer chips.
Using a scanning tunneling microscope, scientists observed nanoscale peaks and dips on a sheet of copper, with angles of a few degrees, researchers report in the July 28 Science. “When we saw that, we were absolutely shocked,” says materials scientist John Boland of Trinity College Dublin. Conventional wisdom was that the copper would lay mostly flat.