A magnetoresistive sensor having a hard magnetic pinning layer with an
engineered magnetic anisotropy in a direction substantially perpendicular
to the medium facing surface. The hard magnetic pinning layer may be
constructed of CoPt, CoPtCr, or some other magnetic material and is
deposited over an underlayer that has been ion beam etched. The ion beam
etch has been performed at an angle with respect to normal in order to
induce anisotropic roughness for example in form of oriented ripples or
facets oriented along a direction parallel to the medium facing surface.
The anisotropic roughness induces a strong uniaxial magnetic anisotropy
substantially perpendicular to the medium facing surface in the hard
magnetic pinning layer deposited there over.