Accession Number:

ADP012226

Title:

Nickel Nanocomposite Thin Films

Descriptive Note:

Corporate Author:

NORTH CAROLINA STATE UNIV AT RALEIGH

Report Date:

2001-11-01

Pagination or Media Count:

7.0

Abstract:

Nickel was deposited on epitaxial TiN matrix layer grown on Si 100 substrate by pulsed laser deposition process PLD. Transmission electron microscopy TEM study shows that nanoparticles formed are single crystals with two kinds of epitaxial relationship with respect to matrix TiN. One is cube on cube, where 200 Ni 200 TiN 200 Si and 02 2 Ni 02 2 TiN 02 2 Si. The particles grown in this orientation have a trapezoidal morphology in 011 projection. The other involves a 90 deg rotation with respect to 011 direction of TiN matrix zone axis, where 0 22 Ni 200 TiN 200 Si and 200 Ni 02 2 TiN 02 2 Si. The particles grown in this rotated orientation have a triangular morphology in 011 projection and a smaller lattice constant compared with that of pure nickel. The possible mechanism of forming these two epitaxial orientations is discussed. Superconducting quantum interference device SQUID magnetometer was used for magnetic measurements. In order to investigate the effect of texturing on magnetic properties of nanoparticles, results were compared with those obtained from Ni nanoparticles grown on amorphous Al2O3 matrix layer in previous research. It was found that both blocking temperature and coercivity of Ni nanoparticles grown on epitaxial TiN matrix are significantly higher than that of Ni grown on amorphous Al2O3. The higher value of coercivity is possibly associated with the stronger tendency of crystallographically oriented particles to retain their magnetic moments in the presence of reversing magnetic field.

Subject Categories:

  • Properties of Metals and Alloys
  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE