Theoretical analysis of initial adsorption of high-κ metal oxides on In_x Ga_(1-x) As (0 0 1) - (4×2) surfaces

摘要

Ordered, low coverage to monolayer, high- κ oxide adsorption on group III rich InAs (0 0 1) - (4×2) and In_(0.53)Ga_(0.47) As (0 0 1) - (4×2) was modeled via density functional theory (DFT). Initial adsorption of HfO_2 and ZrO_2 was found to remove dangling bonds on the clean surface. At full monolayer coverage, the oxide-semiconductor bonds restore the substrate surface atoms to a more bulklike bonding structure via covalent bonding, with the potential for an unpinned interface. DFT models of ordered HfO_2 / In_(0.53)Ga_(0.47)As (0 0 1) - (4×2) show it fully unpins the Fermi level.