Characterization of chevron‐shaped permalloy magnetic memory elements by four magnetic imaging techniques

Abstract

Scanning auger microscopy (SAM) and the recently developed scanning electron microscopy with polarization analysis (SEMPA) are easily combined analytical techniques which provide quantitative submicrometer images of X-, Y-, and Z-axis spin polarization components of magnetization. SAMEEMPA, along with three established magnetic imaging techniques (Bitter colloidal, longitudinal magneto-optic Kerr microscopy, and the Fresnel mode of Lorentz microscopy), was used t o characterize a chevron-shaped permalloy magnetic memory element. Reflected light and secondary electrons were used to image the topography, Auger electrons identified and imaged the elemental composition. Reflected light, transmitted electrons, and secondary electrons were used to image the magnetic microstructure. The Bitter colloidal images showed only the delineation of the domain walls, and the longitudinal magneto-optic Kerr microscopy images produced similar results. The Lorentz microscopy images provided the most qualitative magnetization information. SAMEEMPA was the only technique to combine elemental information and quantitative magnetization information with images having submicrometer resolution.

Imaging and colour coding of magnetic domains by kerr scanning optical microscopy

“…Besides the Bitter powder technique, scanning electron microscopy (SEM) with spin-polarized electrons, and the magnetic contrast types 1 and 2 in conventional SEM, Kerr microscopy is one method of imaging magnetic domains and determining the direction of magnetization (Cameron and Eberle 1991). The rotation of the plane of linearly polarized light after reflection at a ferromagnetic specimen results in an intensity modulation after passing an analyser.…”