Patent ID: 7656611
Filing Date: 2010-02-02
Classification: G11B

Abstract:
1. A perpendicular write head employed to write data to a perpendicular magnetic disc, the perpendicular write head comprising: a main pole having a surface area and comprising high moment magnetic layers laminated with both soft magnetic layers and non-magnetic layers to cause a combination of antiferromagnetic coupling (AFC) and ferromagnetic coupling (FC) of stacks of layers, a non-magnetic separation layer, separating two of the stacks and each of the two stacks including, the non-magnetic separation layer causing AFC between the high magnetic moment layers of the stacks, and the second layer of each stack causing FC between the first and third layers of each stack; and a return pole connected to the main pole by a back gap closure at a distal end and separated from the main pole by a gap at an air bearing surface (ABS), a write coil positioned between the main pole and the return pole, wherein the surface area of the return pole at the ABS is substantially larger than the surface area of the main pole at the ABS, further wherein upon writing data to the perpendicular magnetic disc, a time-varying write current is caused to flow through the write coil, which in turn produces a time-varying magnetic field through the main pole and the return pole, the disc is then passed by the ABS at a predetermined distance such that the perpendicular magnetic disc is exposed to magnetic field, a closed magnetic path for flux from the perpendicular write head to the perpendicular magnetic disc travels from the main pole, through the perpendicular magnetic disc and returns to the perpendicular write head through the return pole.