Synthesis and structure of Ag-Si nanoparticles obtained by the electron-beam evaporation/condensation method

Metal-semiconductor composite Ag-Si nanostructures, including Ag/Si core-shell nanoparticles, have been synthesized for the first time by a high-efficiency evaporation/condensation method using relativistic electron beam. In the Ag/Si core-shell nanoparticles, the core is crystalline, while the shell consists of amorphous silicon. It is found that the synthesis of these particles requires taking into account the difference in the saturated vapor pressures of evaporated components. The dependences of the particle size on the electron beam power at the evaporation stage and the pressure of argon at the condensation stage have been studied. It is established that (i) the main process of Ag/Si nanoparticle formation is coagulation and (ii) the Si shell formation decreases the size of particles.