The p-type conduction and Schottky junction of Ag-doped ZnSnN2

The p-type conduction of Ag-doped ZnSnN2 (AZTN) is studied with experiments and density functional theory (DFT) calculation. The experimental results show that doping ZnSnN2 with Ag introduces no impurity phase but reduces the optical bandgap. The AZTN samples are p-type conductive with hole density of 1015–1016 cm−3 and the p-type origin is likely the doped Ag atoms which very possibly substitute Zn or Sn in the cation sublattice. These observations are consistent with the DFT calculation. The p-type conduction of the AZTN samples is further revealed by the Ohmic contact to Pt and the Schottky contact to Ag. The latter is demonstrated with the rectifying IV curves and the energy band alignment measured with ultraviolet photoelectron spectroscopy. The current transport mechanism of the AZTN\Ag Schottky junction is thermionic emission.