Patent ID: 7466524
Filing Date: 2008-12-16
Classification: G11B

Abstract:
1. A method for use in reading data from a magnetic storage medium with use of a read sensor, the method comprising: providing a read sensor having an antiparallel (AP) self-pinned layer structure for magnetically biasing a free layer in the read sensor and a spacer layer in between the AP self-pinned layer structure and the free layer, the AP self-pinned layer structure including a first AP pinned layer, a second AP pinned layer formed in closer proximity to the spacer layer than the first AP pinned layer, and an antiparallel coupling (APC) layer formed between the first and the second AP pinned layers, the read sensor being without an antiferromagnetic (AFM) layer for pinning the AP self-pinned layer structure which is instead self-pinned by magnetostriction and air bearing surface stress, and wherein a thickness of the first AP pinned layer is greater than a thickness of the second AP pinned layer to produce a net magnetic moment of the AP self-pinned layer structure in a first direction; and causing a sense current to be driven through the read sensor to produce a magnetic field in the same first direction of the net magnetic moment, which reduces the likelihood of amplitude flip associated with the AP self-pinned layer structure.