Patent ID: 8133363
Filing Date: 2012-03-13
Classification: B82Y,G01R,G11B

Abstract:
1. A method of fabricating a dual magnetic tunnel junction (MTJ) sensor, the method comprising: sputter depositing the multilayer dual MTJ sensor including a first magnetic tunnel junction (MTJ) stack having a first tunnel barrier layer, a second magnetic tunnel junction (MTJ) stack having a second tunnel barrier layer, and a longitudinal bias stack disposed between the first and second MTJ stacks; annealing the dual MTJ sensor at a first temperature in a first magnetic field oriented in a transverse direction perpendicular to an air bearing surface for orienting a magnetization of at least one layer of each of the first and second MTJ stacks in a direction perpendicular to the air bearing surface; and annealing the dual MTJ sensor at a second temperature in a second magnetic field oriented in a longitudinal direction parallel to said air bearing surface for orienting a magnetization of at least one layer of the longitudinal bias stack in a direction parallel to the air bearing surface, wherein said second temperature is less than said first temperature and said second magnetic field has a magnitude smaller than said first magnetic field.