The thinnest films of copper look flat, but they aren’t

Newfound nanolandscape of valleys and ridges may impact efficiency of electronics

microscope image of copper

COPPER PEAKS  A scanning tunneling microscope helped scientists catch the first-ever glimpse of the tiny peaks and valleys found on a thin sheet of copper. This section of metal is about 50 nanometers wide.

X. Zhang et al/Science 2017

Like the surface of an alien planet, thin sheets of copper display a complex topography of ridges and valleys.