Abstract :
A magnetic force microscopy is used to examine the domain walls in nickel and cobalt films deposited by argon ion
sputtering. Thin nickel films deposited at high substrate temperatures exhibit coexistent Bloch and Neel walls. Films grown at
room temperature display alternative Bloch lines with cap switches. These films agglomerate to form grains after annealed at
high temperatures. The film composed of larger grains behaves better nucleation implying magnetic domains of closure, while
the film composed of smaller grains exhibits more defects implying alternative Bloch lines. We have also observed domain
displacements and cap switches, which occur due to precipitation of particles in small grain size films. Stripe domains are
observed for film thicknesses larger than 100 nm. They become zigzag cells when an external field of 1.5 T is applied
perpendicular to the surface of the films. This experiment indicates that the domain sizes in thin films and the strip widths for
thick films both depend on the square-root of the film thickness, which varies from 5 to 45 nm and from 100 to 450 nm,
respectively
