Self limiting atomic layer deposition of Al2O3 on perovskite surfaces: a reality?

Abstract

The feasibility of self-saturated atomic layer deposition of Al₂O₃ on an organolead halide perovskite (MAPbI_3−xCl_x) surface through a well known trimethylaluminium (TMA)–water (H₂O) chemistry is studied. Though the sequential dosages of reactants form films on the perovskite surfaces, a self saturated growth is never observed. Self-saturation leads to the degradation of the material. Both experimental and density functional theory calculations are carried out for complete understanding of the growth mechanism of self-limiting Al₂O₃ on the perovskite surface.