INVESTIGADORES
RENTERIA Mario
congresos y reuniones científicas
Título:
Experimental and ab initio study of Ta-doped ZnO semiconductor
Autor/es:
E. L. MUÑOZ, D. RICHARD, P.D. EVERSHEIM, M. RENTERÍA
Lugar:
Ginebra
Reunión:
Conferencia; HFI/NQI2010, 15th International Conference on Hyperfine Interactions & 19th International Symposium on Nuclear Quadrupole Interaction; 2010
Institución organizadora:
Executive Committee del 3th HFI/NQI International Conference
Resumen:
In the last years, ab initio calculations performed in the framework of the DensityFunctional Theory (DFT) have been successfully applied to the study of doped oxidesemiconductors. The Full-Potential Augmented Plane Wave plus local orbitals (FPAPW+lo) method enables to determine the Electric-Field-Gradient tensor (EFG) atimpurity sites localized in cation sites of the host structure with very goodprecision. From an ab initio - experimental study, the electronic structure andstructural relaxations produced by the inclusion of the Perturbed Angular Correlation(PAC) tracers in the host system can be determined [1,2,3] . In this work, wepresent PAC results in polycrystalline ZnO semiconductor implanted with(181Hf-->)181Ta probes. The FP-APW+lo calculations in Ta-doped ZnO were carried outusing the supercell method and varying self-consistently the charge state of theimpurity. Ta is a triple donor impurity with respect to Zn2+ in ZnO and thus it canloose 1, 2 o 3 donor electrons under certain circumstances. The comparison betweenthe experimental EFG results and our ab initio predictions suggests that the Taimpurity may be in a completely ionized charge state, i.e., with the 3 donorelectrons removed from the impurity.