Pure silicon plasma in a helicon plasma deposition system

Abstract

A plasma containing only silicon atoms and ions has been obtained by electron-beam evaporation of solid silicon through a helicon rf plasma source. The density of the silicon plasma in the diffusion chamber is 3–5×1010 cm−3, and the electron temperature 12 eV. These plasma conditions correspond to a predicted deposition rate from silicon ions of 230±60 nm/min, comparable to the deposition rate of 250 nm/min obtained using the same evaporation conditions, without generating a plasma. The large contribution of silicon ions, the high deposition rate, and the absence of other species such as hydrogen or argon, leads to novel conditions for plasma assisted deposition.