Pm. Kopalidis et J. Jorne, MODELING AND EXPERIMENTAL STUDIES OF A REACTIVE ION ETCHER USING SF6 O2 CHEMISTRY/, Journal of the Electrochemical Society, 140(10), 1993, pp. 3037-3045
A mathematical model of a showerhead-type reactive ion etching reactor
using SF6/O2 chemistry is developed. Experimental measurements of the
plasma density, electron energy, and exit gas composition are used to
provide information on the gas-phase reactions taking place and the v
alues for the kinetic rate constants. The concentration distributions
of the various molecules and radicals are obtained by solving numerica
lly the mass balances with finite differences. Surface recombination a
nd competition between flourine and oxygen atoms to absorb on the sili
con surface are considered, and the chemical etch rate of silicon is c
alculated. A correlation between the activation energy of the etching
reaction and the energy and density of bombarding ions is obtained by
comparing the calculated chemical etch rate distribution with the one
measured experimentally.