• Alumina ALD;
  • Atomic layer deposition;
  • Reaction kinetics;
  • Simulation;
  • Transition state theory


A physically based model of atomic layer deposition (ALD) surface reaction dynamics is developed and applied to alumina ALD with water and trimethylaluminum precursors. The time-dependent growth surface composition is modeled by computing the equilibrium precursor adduct surface concentrations during each half-reaction and the rate constants of the ligand exchange reactions using transition state theory. To describe the continuous cyclic operation of the deposition reaction system, a numerical procedure to discretize limit-cycle solutions is developed and used to distinguish saturating growth per cycle (GPC) from non-saturating (gpc) conditions. The transition between the two regimes is studied as a function of precursor partial pressure, exposure time, and temperature.