Growth mechanism of atomic layer deposition of zinc oxide: A density functional theory approach

Atomic layer deposition of zinc oxide (ZnO) using diethylzinc (DEZ) and water is studied using density functional theory. The reaction pathways between the precursors and ZnO surface sites are discussed. Both reactions proceed by the formation of intermediate complexes on the surface. The Gibbs free energy of the formation of these complexes is positive at temperatures above ∼120 °C and ∼200 °C for DEZ and water half-reactions, respectively. Spectroscopic ellipsometry results show that the growth per cycle changes at approximately the same temperatures.