Investigations on energy fluxes in magnetron sputter-deposition: implications for texturing and nanoporosity of metals

By means of TRIM.SP Monte-Carlo simulations the energetic and angular distr ibutions of sputtered atoms and reflected argon-neutrals were calculated fo r sputtering a variety of elemental targets. The power density at the subst rate during sputter deposition was measured by a calorimetric method. The c ombination with measurements of the atomic deposition rate resulted in the determination of the total amount of the energy input per incorporated atom . For low pressure sputtering at 0.4 Pa, the experimental data are well des cribed by contributions due to plasma irradiation, the heat of condensation of deposited atoms, their kinetic energy, and the kinetic energy of the re flected argon-neutrals. For increased pressure, there is an increased contr ibution of electrons to probe heating. The combination of experimental and a priori calculated data results in empirical rules for the energies of the sputtered and reflected species, which allow an estimate of the energy inp ut during sputter-deposition for every given elemental film material. Stron g thermalization of particles at high-pressure deposition resulted in highl y porous films with a density below 50% of the bulk material. It is conclud ed that for circular planar magnetrons and static deposition mode the bomba rdment of the growing film is inhomogeneous, which results in laterally inh omogeneous crystallographic properties. (C) 2000 Elsevier Science B.V. All rights reserved.