Seagate Technology Incorporated

Denis O'Donnell

Marcus Winston Ormston

Kevin Anthony McNeill

Sameh Hassan

Robert William Lamberton

Alexey Dobrynin

Zhiran Wang

Yuqing Du

A read sensor having a bearing surface and an antiferromagnetic (AFM) layer recessed from the bearing surface. The read sensor includes a synthetic antiferromagnetic (SAF) structure over the AFM layer. The SAF structure includes a recessed lower pinned layer, an upper pinned layer, a reference layer and a stabilization feature. The stabilization feature may include deliberate reduction of the antiferromagnetic coupling energy density between the upper pinned layer and the reference layer, so that it becomes lower than the first energy density of antiferromagnetic coupling between the upper pinned layer and the lower pinned layer. The stabilization feature may alternatively include an intermediate pinned layer between the lower pinned layer and the upper pinned layer. The intermediate pinned layer is antiferromagnetically coupled to both the lower pinned layer and the upper pinned layer, and at least a portion of the intermediate pinned layer is recessed behind the bearing surface.

Magnetoresistive sensor with recessed antiferromagnetic layer and stabilization feature

A read sensor and fabrication method thereof. The method includes forming a bottom stack that includes an antiferromagnetic (AFM) layer, a lower ferromagnetic stitch layer above the AFM layer and a sacrificial cap layer on the lower ferromagnetic stitch layer. The sacrificial cap layer is formed of a material that alloys magnetically with the lower ferromagnetic stitch layer. The method further includes substantially removing the sacrificial cap layer. After substantially removing the sacrificial layer, an upper ferromagnetic stitch layer is deposited on the lower ferromagnetic stitch layer of the bottom stack to form a stitch interface that provides relatively strong magnetic coupling between the lower ferromagnetic stitch layer of the bottom stack and the upper ferromagnetic stitch layer.

Recessed AFM stitch interface engineering

Growing community of inventors

Derry, United Kingdom

Denis O'Donnell