Geometric and electronic structures of iridium(III) acetylacetonate in atomic layer deposition of iridium: a first-principles study

Abstract

In order to understand the decomposition of iridium(III) acetylacetonate in the atomic layer deposition process of iridium, the geometric structures, electronic structures and fracturing process of ligands of iridium(III) acetylacetonate were investigated on the basis of the density functional theory and periodical slab model. The results indicated that the optimized structure of iridium(III) acetylacetonate molecule has a high degree of symmetry in 3D space, the molecular core composed of planar structure and perpendicular with each other. The highest occupied state and the lowest unoccupied state were obtained by density of state analysis, which mainly due to the contribution of different orbits of the hydrogen, carbon, oxygen and iridium atoms. Atomic layer deposition can only happen within a reasonable temperature range, when temperature is higher than 623 K, the reaction is a decomposition process instead of atomic layer deposition.