Scissoring-type current-perpendicular-to-the-plane (cpp) magnetoresistive sensor with free layers having etch-induced uniaxial magnetic anisotropy

A scissoring-type current-perpendicular-to-the-plane (CPP) magnetoresistive read head for reading magnetically recorded data from tracks on a magnetic recording medium, the head comprising:

• a first shield layer of magnetically permeable material;
• an underlayer on the first shield;
• a first ferromagnetic free layer on the underlayer and having an etch-induced uniaxial magnetic anisotropy and an in-plane magnetic moment substantially parallel to said uniaxial anisotropy in the absence of an applied magnetic field;
• a nonmagnetic spacer layer on the first ferromagnetic layer;
• and
• a second ferromagnetic free layer on the spacer layer and having an etch-induced uniaxial magnetic anisotropy and an in-plane magnetic moment substantially parallel to said second free layer's uniaxial anisotropy, the second free layer's magnetic moment being generally orthogonal to the first free layer's magnetic moment in the absence of an applied magnetic field, said first and second free layer magnetic moments being free to rotate in opposite directions in the presence of a magnetic field from magnetically recorded data on the medium;
• a capping layer on the second free layer;
• and
• a second shield of magnetically permeable material on the capping layer.

A method for making a scissoring-type current-perpendicular-to-the-plane (CPP) magnetoresistive sensor comprising:

• providing a substrate;
• depositing an underlayer on the substrate;
• depositing a first ferromagnetic free layer on the underlayer;
• depositing a nonmagnetic spacer layer on the first ferromagnetic layer;
• depositing a second ferromagnetic free layer on the spacer layer;
• and
• after depositing at least one layer selected from a first group consisting of said underlayer and said first free layer, directing an ion beam to said at least one layer from said first group at an oblique angle relative to a normal to the surface of said at least one layer from said first group to directionally etch the surface of said at least one layer from said first group;
• after etching the surface of said at least one layer from said first group, rotating the substrate relative to the ion beam about a normal to the surface of the substrate;
• and
• after depositing at least one layer selected from a second group consisting of said spacer layer and said second free layer, directing an ion beam to said at least one layer from said second group at an oblique angle relative to a normal to the surface of said at least layer from said second group to directionally etch the surface of said at least one layer from said second group.