Details

Autor(en) / Beteiligte

• Volnianska, O
• Boguslawski, P

Titel

GGA + U study of native point defects in ZnRh sub(2)O sub(4)

Ist Teil von

• Journal of physics. D, Applied physics, 2014-11, Vol.47 (46), p.1-10

Erscheinungsjahr

2014

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ZnRh sub(2)O sub(4) spinel is the one of the most promising transparent conducting oxides fot-applications in optoelectronic technology. Energy levels and formation energies of native point defects, i.e. vacancies (V), interstitials (I), and cation antisites in ZnRh sub(2)O sub(4) were analysed. Generalized gradient approximation (GGA) was supplemented by the +U on-site corrections imposed on d(Rh) and p(O) states. The inclusion of the pronounced distortions of the anion sublattice was necessary to obtain the correct band gap. U was treated as a free parameter, which allowed for the systematic study of the U-induced changes of the defect states. A diagram of the thermodynamic phase stability of ZnRh sub(2)O sub(4) was obtained. Zn sub(Rh), is the dominant acceptor that can be responsible for the observed p-type conductivity in ZnRh sub(2)O sub(4). The low formation energy of Zn sub(Rh) can make the intentional n-doping difficult. In the O-rich conditions the second important acceptor is V sub(Zn). The two dominant donors that can compensate Zn sub(Rh), in Zn-rich and O-rich conditions are V sub(O) and Rh sub(Zn), respectively. Growth conditions leading to the lowest concentrations of native defects were identified. Due to the pronounced occupancy dependence of the +U term. V sub(O) and Rh sub(Zn) are "negative-U sub(eff)" centres.