Journal of Electronic Materials

, Volume 33, Issue 11, pp 1298–1302 | Cite as

Origin of room-temperature ferromagnetism in cobalt-doped ZnO

  • S. Ramachandran
  • Ashutosh Tiwari
  • J. Narayan
Special Issue Paper

Abstract

Thin films of ZnO doped with cobalt have been grown by the pulsed laser deposition (PLD) technique in different temperatures ranging from 500°C to 650°C. The films grown on sapphire c-plane single crystal were found to be highly epitaxial. Magnetic properties of these films were studied, and the films exhibited ferromagnetic characteristics at room temperature. Detailed structural and microstructural characterization was performed to correlate the fate of the magnetic impurities, i.e., cobalt, and the cause of magnetic properties. It is established from this work that the magnetic properties of these films are inherent to the system, and any presence of second phase/nanoclusters/precipitates are ruled out as the cause of magnetic properties. The techniques used to establish these were conventional and high-resolution transmission electron microscopy (HRTEM) along with electron-energy loss spectroscopy (EELS) and scanning transmission electron microscopy-atomic number (STEM-Z) contrast studies.

Key words

ZnO Co ferromagnetism pulsed laser deposition 

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Copyright information

© TMS-The Minerals, Metals and Materials Society 2004

Authors and Affiliations

  • S. Ramachandran
    • 1
  • Ashutosh Tiwari
    • 1
  • J. Narayan
    • 1
  1. 1.NSF Center for Advanced Materials and Smart Structures, Department of Materials Science and EngineeringNorth Carolina State UniversityRaleigh

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