Spin valve having copper oxide spacer layer with specified coupling field strength between multi-layer free and pinned layer structures
View Patent ↗A magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuO x . Plasma smoothing of the upper surface of the pinned magnetic layer is conducted prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.
1. A magnetic head including a spin valve sensor comprising:
a magnetic shield layer (S 1 ) being fabricated above a substrate base;
a first electrical insulation layer (G 1 ) being fabricated above said S 1 layer;
a spin valve sensor structure being disposed above said G 1 layer;
wherein said spin valve sensor structure includes a seed layer being fabricated above said G 1 layer, an antiferromagnetic layer being disposed above said seed layer, a pinned magnetic layer being comprised of a laminated structure including layers of CoFe, Ru, nd CoFe and being disposed above said antiferromagnetic layer, a spacer layer being comprised of CuO x and being disposed upon said pinned magnetic layer, and a free magnetic layer being comprised of a laminated structure including layers of CoFe and NiFe and being dispose upon said spacer layer; and
wherein a magnetic coupling field exists across said CuO x spacer layer having a coupling field strength of from −5 Oe to −15 Oe, and said CuO x spacer layer is formed with a thickness of from 16 Å to 20 Å.
2. A magnetic head as described in claim 1 , wherein said coupling field strength is approximately −10 Oe, and said CuO x spacer thickness is approximately 17 Å.
3. A magnetic head as described in claim 1 wherein said pinned magnetic layer laminated structure includes layers of CoFe, Ru, and CoFe having thicknesses of 17 Å, 8 Å and 17 Å respectively.
4. A magnetic head as described in claim 1 wherein said free magnetic layer laminated structure includes layers of CoFe and NiFe having thicknesses of 10 Å and 20 Å respectively.
5. A hard disk drive including a magnetic head including a spin valve sensor comprising:
a magnetic shield layer (S 1 ) being fabricated above a substrate base;
a first electrical insulation layer (G 1 ) being fabricated above said S 1 layer;
a spin valve sensor structure being disposed above said G 1 layer;
wherein said spin valve sensor structure includes a seed layer being fabricated above said G 1 layer, an antiferromagnetic layer being disposed above said seed layer, a pinned magnetic layer being comprised of a laminated structure including layers of CoFe, Ru, and CoFe and being disposed above said antiferromagnetic layer, a spacer layer being comprised of CuO x and being disposed upon said pinned magnetic layer, and a free magnetic layer being comprised of a laminated structure including layers of CoFe and NiFe and being disposed upon said spacer layer; and
wherein a magnetic coupling field exists across said spacer layer having a coupling field strength of from −5 Oe to −15 Oe, and said spacer layer is formed with a thickness of from 16 Å to 20 Å.
6. A hard disk drive including a magnetic head as scribed in claim 5 wherein said coupling field strength is approximately −10 Oe, and said CuO x spacer thickness is approximately 17 Å.
7. A hard disk drive including a magnetic head as described in claim 5 wherein said pinned magnetic layer laminated structure includes layers of CoFe, Ru, and CoFe having thicknesses of 17 Å, 8 Å and 17 Å respectively.
8. A hard disk drive including a magnetic head as described in claim 5 wherein said free magnetic layer laminated structure includes layers of CoFe and NiFe having thicknesses of 10 Å and 20 Å respectively.