Novel seed layers for fabricating spin valve heads for ultra-high density recordings
AssigneeHeadway Technologies, Inc.
InventorsC.T. Horng, Hui-Chuan Wang, Ru-Ying Tong, Chyu-Jiuh Trong
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Abstract
A novel seed layer comprising an approximately 30 angstrom thick layer of NiCr whose atomic percent of Cr is 31%, is used to form a single bottom spin valve read sensor and a symmetric dual spin valve read sensor having synthetic antiferromagnetic pinned layers. The seed layer permits the use of extremely thin (approximately 80 angstroms) MnPt pinning layers as well as extremely thin pinned and free layers so that the sensors can be used to read recorded media with densities exceeding 60 Gb/in2. Moreover, the high pinning field and optimum magnetostriction produces an extremely robust sensor.
Claims40
A bottom spin valve sensor element with a novel seed layer and synthetic antiferromagnetic pinned layer comprising:
- a substrate;
- a NiCr seed layer formed on the substrate, the atomic percentage of Cr in said seed layer being approximately 31%;
- an antiferromagnetic pinning layer formed on said seed layer;
- a synthetic antiferromagnetic (SyAF) pinned layer formed on said pinning layer;
- a non-magnetic spacer layer formed on said SyAF layer, the surface of said spacer layer not contacting said SyAF layer being treated to form an oxygen surfactant layer (OSL);
- a ferromagnetic free layer formed on the OSL of said treated spacer layer;
- a capping layer formed on said ferromagnetic free layer:
A symmetric dual spin valve sensor element with a novel seed layer and synthetic antiferromagnetic pinned layers comprising:
- a substrate;
- a NiCr seed layer formed on the substrate, the atomic percentage of Cr in said seed layer being approximately 31%;
- a first antiferromagnetic pinning layer formed on said seed layer;
- a first synthetic antiferromagnetic (SyAF) pinned layer formed on said first antiferromagnetic pinning layer;
- a first non-magnetic spacer layer formed on said SyAF layer, the surface of said spacer layer not contacting said SyAF layer being treated to form an oxygen surfactant layer (OSL);
- a ferromagnetic free layer formed on the OSL of said treated spacer layer;
- a second non-magnetic spacer layer formed on said ferromagnetic free layer, the surface of said spacer layer not contacting said free layer being treated to form an oxygen surfactant layer (OSL);
- a second synthetic antiferromagnetic (SyAF) pinned layer formed on the OSL of said second non-magnetic spacer layer;
- a second antiferromagnetic pinning layer formed on said second SyAF layer;
- a capping layer formed on said second antiferromagnetic pinning layer.
A method for forming a bottom spin valve sensor element with a novel seed layer and synthetic antiferromagnetic pinned layer comprising:
- providing a substrate;
- forming an NiCr seed layer on the substrate, wherein the atomic percentage of Cr in said seed layer is approximately 31%;
- forming an antiferromagnetic pinning layer on said seed layer;
- forming a synthetic antiferromagnetic (SyAF) pinned layer on said pinning layer;
- forming a non-magnetic spacer layer on said SyAF layer;
- treating the surface of said spacer layer not contacting said SyAF layer to form an oxygen surfactant layer (OSL) thereon;
- forming a ferromagnetic free layer on the OSL of said treated spacer layer;
- forming a capping layer on said ferromagnetic free layer;
- magnetizing said sensor element.
A method for forming a symmetric dual spin valve sensor element with a novel seed layer and synthetic antiferromagnetic pinned layers comprising:
- providing a substrate;
- forming a NiCr seed layer on the substrate, the atomic percentage of Cr in said seed layer being approximately 31%;
- forming a first antiferromagnetic pinning layer on said seed layer;
- forming a first synthetic antiferromagnetic (SyAF) pinned layer on said pinning layer;
- forming a first non-magnetic spacer layer on said SyAF layer, the surface of said spacer layer not contacting said SyAF layer being treated to form an oxygen surfactant layer (OSL) thereon;
- forming a ferromagnetic free layer on the OSL of said treated non-magnetic spacer layer;
- forming a second non-magnetic spacer layer formed on said ferromagnetic free layer, the surface of said spacer layer not contacting said ferromagnetic free layer being treated to form an oxygen surfactant layer (OSL) thereon;
- forming a second synthetic antiferromagnetic (SyAF) pinned layer on said oxygen surfactant layer (OSL) of said non-magnetic spacer layer;
- forming a second antiferromagnetic pinning layer on said SyAF pinned layer;
- forming a capping layer on said pinning layer;
- magnetizing said sensor element.
Dependencies are inferred from the claim text.