Computer simulations of crater profiles in glow discharge optical emission spectrometry: comparison with experiments and investigation of the underlying mechanisms

The crater profiles obtainable with glow discharge sputtering are calculated for a wide range of current–voltage conditions, and comparison is made with experimental data for exactly the same geometry and conditions. The agreement is fairly good, except at high electrical current and low voltage. This good agreement suggests that the model takes into account the correct underlying mechanisms responsible for the crater shape, and that it can be used to predict optimum conditions for flat crater profiles. It is concluded from the model that the characteristic crater shape is determined by the electric potential distribution in front of the cathode, the radial distribution of fluxes and energies of the species bombarding the cathode, as well as the redeposition of sputtered atoms at the cathode surface, which is in correspondence to previous findings.