The metal flux from a rotating cylindrical magnetron: a Monte Carlo simulation

Abstract

A Monte Carlo simulation of the metal flux from a small scale rotating cylindrical magnetron is presented. The model describes the sputtered particles trajectories through the gas in a user definable 3D set-up. The ejection positions of the sputtered particles are generated according to the simulated ion current density on the target. The thermal motion of the background gas is included, with collisions modelled based on either quantum chemical or screened Coulomb interaction potentials. Experimental characterization of the metal flux was performed for Cu, Al and Ti targets at a range of argon pressures (0.3–1 Pa) by measuring deposition rate distributions. A comparison with preliminary simulations showed the importance of a correct description of the nascent angular distribution of the sputtered particles. Therefore, this distribution was not considered as given by sputter simulation or analytical formula, but was instead reconstructed from the low pressure experimental deposition profiles. The typical heart-like shaped emission observed at low energy sputtering was found and a comparison was made with results from binary collision approximation modelling. The spatial, pressure and material dependence of the metal flux in the chamber was then simulated and found to be in good agreement with the experiment.

Angular-resolved energy flux measurements of a dc- and HIPIMS-powered rotating cylindrical magnetron in reactive and non-reactive atmosphere

“…Figure 3(a) shows that the deposition rate drops when the magnets (and hence the racetrack) are rotated away from the quartz balance. For DC, this shape can be perfectly simulated using the test-particle Monte Carlo code SIMTRA [27]. Furthermore, a more than 75% decrease can be observed for the deposition rate in HIPIMS mode (with a 20µs long pulse), compared to DC mode.…”

Time-domain and energetic bombardment effects on the nucleation and coalescence of thin metal films on amorphous substrates

“…Ar ions with an energy corresponding to the cathode voltage for each simulated condition were used as bombarding species and the initial energy and angular distribution of the sputtered Ag atoms were obtained. These distributions were used as input together with the experimental gas pressure and chamber geometry to simulate the interactions of the sputtered species with the buffer gas (Ar) en route to the substrate (employing SIMTRA) [19] and obtain the energy and the time-of-flight of the sputtered species arriving at the substrate.…”

Sputter Deposition Processes

“…Several models have been proposed [47] to simulate the transport of sputtered particles. Recently, K. Van Aeken et al [48] have developed a user-friendly shareware model SiMTRA (SiMulation of TRAnsport). This flexible model enables calculation of the energy, direction, and flux of sputtered particles incident on every defined surface in the vacuum chamber.…”