Deposition of Tungsten Nanoparticles for Potential Use in Dispenser Cathodes

Dispenser cathodes have attracted attention in both industrial and academic research for a long time, due to their application as high-brightness electron sources. Since most modern cathodes utilize tungsten as the base material, it is useful to investigate how novel forms of tungsten can influence a cathode. In the present study, nanoscale tungsten particles were generated by physical vapor deposition and deposited onto substrates, to gauge the effectiveness of generating a tungsten coating that can enhance electron emission. These nanoparticles were characterized by scanning and transmission electron microscopy. The tungsten particles formed a continuous nanoporous structure, along with discrete larger particles on the substrate.