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Keywords:

  • dislocations;
  • AlN;
  • doping;
  • electronic properties;
  • nanowires

Abstract

The effect of threading dislocations on the electronic properties of AlN is investigated through density functional theory calculations on the six atom ring core of c -screw dislocations. Additional calculations are performed in order to elucidate the effect of doping through decoration of the dislocation cores by Indium and Oxygen atoms. Substitution of Al (N) core atoms by In (O) impurities as well as incorporation of a rhombohedral In2O3 structural unit in the core, are examined. It is revealed that multiple levels are induced in the band gap of AlN in all cases and screw dislocations are identified as conduction pathways to charge carriers. This feature is exemplified when rhombohedral In2O3 is incorporated in the cores. The presence of these dopants shall augment the conductivity along the dislocation line and new prospects arise for AlN threading dislocations since, following the “dislocation technology” scheme, the role of conductive nanowires in semiconducting thin films is appointed to doped screw dislocations (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)