Molecular Dynamics Simulations of Platinum Plasma Sputtering: A Comparative Case Study

Abstract

Molecular Dynamics simulations are carried out for investigating atomic processes of platinum sputtering. Sputtered Pt atom energy distribution functions (EDF) are determined at different sputtering argon ionenergies: 100, 500, and 1000 eV. Calculated EDF show a cross-over from Thompson theory to binary collision model when increasing argon ion energy and Pt atom sputtered energy. Implanted argon ion number is depending on its kinetic energy, while it is not the case in binary collision approximation. Finally sputtering yields are greater for Thompson theory than for binary collision model at low energy, but converge to the close values at high energy.

Molecular Dynamics Simulations for Plasma‐Surface Interactions

“…It should be stressed here, however, that in particular cases it may be more appropriate to select velocities from a non‐Maxwellian distribution function, as would, e.g., be the case when considering sputtered atoms or ions in a plasma sheath. A recent example of this procedure is given in ref …”

“…Sputtering is probably the easiest plasma‐surface process to model using molecular dynamics, and it was in fact the first typical process occurring in plasmas to be simulated by MD . Although it is conceptually simple enough to simulate, some care must be taken in treating the energy transfer and ion accumulation in the target . In practice, an ion is positioned at a distance larger than the cutoff distance above the surface, and given a velocity corresponding to the required ion energy.…”

“…Indeed, at low plasma pressure, the distribution is typically not Maxwellian due to the small collision number. Recently, the sputtered atom energy distribution was compared with available standard models . Future work in the field should consider sputtering of oxide target and reactive sputtering.…”

“…A recent example of this procedure is given in ref. [38] Hyperthermal species are species which have a kinetic energy significantly above thermal energy, in the order of a few eV. Such species can simply be represented by adding the required amount of kinetic energy to the particles.…”

Molecular dynamic simulation study of plasma etching L1 FePt media in embedded mask patterning (EMP) process

“…Classical Molecular Dynamics (MD) simulation has been used to understand the ion sputtering and surface reaction kinetics during etching process. 9,[12][13][14] In MD model of etch process, substrate atoms, etchant particles (ions) and neutrals (molecules) are constructed in one ensemble with defined interatomic potentials. The time evolution of these particles are tracked and updated via solution of Newton's equation of motions.…”