On the band structure lineup of ZnO heterostructures

The interface-induced gap states (IFIGS) are the fundamental mechanism which determines the band structure lineup at semiconductor interfaces. The valence-band offsets of semiconductor heterostructures are given by the difference of the respective IFIGS branch-point energies and electric-dipole terms which may be omitted for elemental group-IV semiconductors, SiC, as well as the III-V, II-VI, and I - III - VI 2 compounds and alloys. The branch-point energy of ZnO is determined as 3.04 ± 0.21 eV from an analysis of experimental valence-band offsets reported for various ZnO heterostructures.