PURE SILICON PLASMA IN A HELICON PLASMA DEPOSITION SYSTEM

A plasma containing only silicon atoms and ions has been obtained by e lectron-beam evaporation of solid silicon through a helicon rf plasma source. The density of the silicon plasma in the diffusion chamber is 3-5 x 10(10) cm and the electron temperature 12 eV. These plasma condi tions correspond to a predicted deposition rate from silicon ions of 2 30 +/- 60 nm/min, comparable to the deposition rate of 250 nm/min obta ined using the same evaporation conditions, without generating a plasm a. The large contribution of silicon ions, the high deposition rate, a nd the absence of other species such as hydrogen or argon, leads to no vel conditions for plasma assisted deposition. (C) 1997 American Insti tute of Physics.