Accession Number : ADA328297

Title :   Anisotropy in Epitaxial Films.

Descriptive Note : Final rept. 1 Jun 91-30 Sep 95,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE CENTER FOR MATERIALS SCIENCE AND ENGINEE RING

Personal Author(s) : Thompson, C. V. ; O'Handley, R. C.

PDF Url : ADA328297

Report Date : 13 JUN 1997

Pagination or Media Count : 7

Abstract : Experiments on epitaxial Ni films grown on epitaxial Cu films grown on single crystal (100) Si wafers in a molecular beam epitaxy system modified to make in situ magneto-optic Kerr effect (MOKE) measurements were carried out. Ex situ transmission electron microscopy and wafer curvature measurements were made and it was shown that the onset of misfit accommodation, the decrease in Ni strain with increasing film thickness, and the increase in misfit dislocation density were consistent with existing models for misfit accommodation. In situ MOKE studies and ex situ vibrating sample magnetometry studies of the magnetic consequences of the changing strain with Ni film thickness showed that the magnetic easy axis of the Ni/Cu(001) films was perpendicular to the film plane over the range 1.5 to approximately 6 nm. We have found from these studies that the low-thickness transition from perpendicular to in-plane magnetization with decreasing film thickness (seen also in ultra-thin Fe/Cu and Fe/Ag) is NOT associated with the critical thickness leading to the onset of MD formation, but results instead from a complex interplay of magnetostatic and magnetoelastic energies, and of the Neel magnetic surface anisotropy as well as the surface magneto-elastic anisotropy.

Descriptors :   *FILMS, *EPITAXIAL GROWTH, *ANISOTROPY, DENSITY, MEASUREMENT, THICKNESS, MAGNETIC FIELDS, MAGNETOOPTICS, SINGLE CRYSTALS, ELECTRON MICROSCOPY, TRANSMITTANCE, SURFACES, CURVATURE, DISLOCATIONS, COPPER, NICKEL, WAFERS, KERR MAGNETOOPTICAL EFFECT, MAGNETOMETRY, NEEL TEMPERATURE, MOLECULAR BEAM EPITAXY.

Subject Categories : Inorganic Chemistry
      Crystallography
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE