Hard bias layer for read heads

A magnetoresistive (MR) read head comprising:

• an MR sensor including a free layer and a pinned layer;
• a multi-layer hard bias layer positioned adjacent the MR sensor for stabilizing the free layer of the MR sensor;
• and
• a pair of lead layers operatively coupled to the MR sensor;
• wherein a product of the moment (Ms) and the thickness (t) of a lower layer of the hard bias layer is greater than a product of the moment (Ms) and the thickness (t) of the free layer of the MR sensor,
• wherein the multi-layer hard bias layer includes a seed layer formed above the lower layer, and an upper layer formed on the seed layer.

A magnetoresistive (MR) read head, comprising:

• a lower shield layer;
• a lower gap layer located above the lower shield layer;
• an MR sensor located above the lower gap layer, the MR sensor having a free layer;
• a hard bias lower layer located above the lower gap layer, wherein a product of a moment (Ms) and a thickness (t) of the hard bias lower layer is greater than a product of a moment (Ms) and a thickness (t) of the free layer of the MR sensor;
• a seed layer formed above the hard bias layer lower layer;
• a hard bias upper layer formed on the seed layer;
• a pair of lead layers operatively coupled to the MR sensor;
• an upper gap layer located above the MR sensor;
• and
• an upper shield layer located above the upper gap layer.

A method for fabricating a magnetoresistive (MR) read head, comprising:

• forming an MR sensor having a free layer and a pinned layer;
• and
• depositing a multi-layer hard bias layer for stabilizing the free layer of the MR sensor;
• wherein a product of the moment (Ms) and the thickness (t) of a lower layer of the hard bias layer is greater than a product of the moment (Ms) and the thickness (t) of the free layer of the MR sensor
• wherein the multi-layer hard bias layer includes a seed layer formed above the lower layer, and an upper layer formed on the seed layer.