Focused electron-beam induced deposition of plasmonic nanostructures from aqueous solutions

Electron-beam-induced deposition (EBID) is a gas-phase direct-write technique capable of sub-10 nm resolution, with applications in micro- and nanoscale object manipulation, mask repair, and circuit edit. While several high purity materials can be deposited by EBID, the majority of deposits suffer from undesirable co-deposition of organic or inorganic ligands. As a result, impurity incorporation limits EBID application in processes requiring high purity. Recently, a complimentary technique known as liquid phase EBID (LP-EBID) has been shown to drastically improve deposit purity by utilizing precursors without carbon or phosphorous based architectures. Here we demonstrate direct-write deposition of silver nanostructure arrays, with tunable geometry for localized surface plasmon resonance (LSPR) control. Nanoparticle arrays with 55 - 100 nm diameters were obtained. Resonant wavelengths between 550 - 600 nm were achieved and correlated to the observed nanoparticle geometry. These results demonstrate how LP-EBID can be used to provide site-specific deposition for plasmonic devices and additionally open the door to fields inaccessible to traditional gas-phase EBID.