Method of fabrication for read head having shaped read sensor-biasing layer junctions using partial milling

A method for fabricating a read head for a hard disk drive having a read head sensor and a hard bias layer, said read head having a shaped junction between said read head sensor and said hard bias layer, said method comprising:

• A) providing a layered wafer stack to be shaped, said layered wafer stack including a free layer, an AFM layer and a first seed layer;
• B) depositing a single- or multi-layered photoresist mask having no undercut upon said layered wafer stack to be shaped;
• C) providing a milling source which produces an output at a defined angle of projection;
• D) adjusting the angle of said layered wafer stack to be shaped relative to said angle of projection of said milling source at high incidence and razing incidence;
• E) establishing a partial milling range by which milling extends at least through said free magnetic layer, but stops short of milling completely through said first seed layer;
• F) partially milling said layered wafer stack by said output of said milling source to within said partial milling range where said partial milling extends to a partial milling depth having a depth endpoint within said partial milling range, to form the shaped junction:
• and
• G) depositing said hard bias layer in contact with said shaped junction.

A method for fabricating a read head for a hard disk drive having a read head sensor and a hard bias layer, said read head having a shaped junction between said read head sensor and said hard bias layer, said method comprising:

• A) providing a layered wafer stack to be shaped, said layered wafer stack including a free layer, an AFM layer and a first seed layer;
• B) depositing a single- or multi-layered photoresist mask having no undercut upon said layered wafer stack to be shaped;
• C) providing a milling source which produces an output at a defined angle of projection;
• D) adjusting the angle of said layered wafer stack to be shaped relative to said angle of projection of said milling source;
• E) establishing a partial milling range by which milling extends at least through said free magnetic layer, but stops short of milling completely through said first seed layer;
• F) partially milling said layered wafer stack by said output of said milling source to within said partial milling range where said partial milling extends to a partial milling depth having a depth endpoint within said partial milling range, to form the shaped junction, including multiple cycles of milling at both high incidence and razing incidence;
• and
• G) depositing said hard bias layer in contact with said shaped junction.