Painting and Direct Writing of Silver Nanostructures on Phosphate Glass with Electron Beam Irradiation

Surfaces with silver nanostructures are useful, due to their potential to resonate strongly with visible light. This report demonstrates a process for the directed extraction of silver at the surface of a transparent superionic conductor. A focused electron beam incident on superionic AgIAgPO₃ glass results in localized negative charge deposition, which is neutralized by the electrochemical reduction of free silver ions. This process was characterized for beam energies ranging from 1 to 12 kV and primary beam fluence ranging from 50 pC μm^-2 to 35 nC μm^-2. For electron fluence less than 2.5 nC μm^-2 the process produces vibrant coloration of the glass which can be tuned throughout the entire visible spectrum. Fluence greater than 2.5 nC μm^-2 results in the controlled writing of bulk silver on the surface, with a minimum line width as small as 400 nm and narrow gaps as small as 50 nm. The high ionic conductivity of the substrate is shown to be a vital component to the process, allowing the wide range of colors to be produced along with the controlled, nondendritic growth of silver structures.