A magnetic data track used in a magnetic shift register memory system may be
fabricated
by forming a multilayered stack of alternating dielectric and/or silicon layers.
Vias of approximately 10 microns tall with a cross-section on the order of 100
nm100 nm are etched in this multilayered stack of alternating layers. Vias
may be etched form smooth or notched walls. Vias are filled by electroplating layers
of alternating types of ferromagnetic or ferrimagnetic metals. The alternating
ferromagnetic or ferrimagnetic layers are comprised of magnetic materials with
different magnetization or magnetic exchange or magnetic anisotropies. These different
magnetic characteristics allow the pinning of magnetic domain walls at the boundaries
between these layers. Alternatively, vias are filled with a homogeneous ferromagnetic
material. Magnetic domain walls are formed by the discontinuity in the ferromagnetic
or ferromagnetic material that occurs at the notches or at the protuberances along
the via walls.