  We study the effect of the so-called ion potential or non-kinetic energies of
bombarding ions during ionized physical vapor deposition of Cu using molecular
dynamics simulations. In particular we focus on low energy HiPIMS deposition,
in which the potential energy of ions can be comparable to their kinetic
energy. The ion potential, as a short-ranged repulsive force between the ions
of the film-forming material and the surface atoms (substrate and later film),
is defined by the Ziegler-Biersack-Littmark potential. Analyzing the final
structure indicates that, including the ion potential leads to a slightly lower
interface mixing and fewer point defects (such as vacancies and interstitials),
but resputtering and twinning have increased slightly. However, by including
the ion potential the collision pattern changes. We also observed temporary
formation of a ripple/pore with 5~nm height when the ion potential is included.
The latter effect can explain the pores in HiPIMS deposited Cu thin films
observed experimentally by atomic force microscopy.
