Stability of graphite-like ZnO film with Cu doping: First principle study

摘要

The stability of the graphite-like ZnO film has been studied by first principle calculation. By analyzing ZnO films from 5 to 9 layers, the GP (graphite-like) structure turns out to be unstable for the reason that the intrinsic defects produce the additional electrons. By doping Cu into the ZnO thin film, the correlation between band structure, binding energy and integrated state density indicates that the electrons in Cu-3d are strongly coupled with the electrons in O-2p, resulting in Cu 2p electron atoms in adjacent oxygen. The shallow acceptor level is promoted by the Fermi level, which can effectively reduce the concentration of electrons in the film and enhance the intrinsic dipole field, thereby making the ZnO structure ZnO stable.