Dual Free Layer TMR Reader With Shaped Rear Bias and Methods of Forming Thereof

A magnetic recording device comprising a dual free layer (DFL) read head, the DFL read head formed by a method, comprising:

• forming a DFL sensor;
• defining a track width of the DFL sensor, the DFL sensor being disposed at a media facing surface;
• forming synthetic antiferromagnetic (SAF) soft bias (SB) side shields adjacent to the DFL sensor;
• defining a stripe height of the DFL sensor and the SAF SB side shields, the stripe height of the DFL sensor and the SAF SB side shields being substantially equal;
• forming a rear bias (RB) adjacent to the DFL sensor and the SAF SB side shields, the RB being recessed from the media facing surface;
• defining a track width of the RB, the track width of the RB being greater than the track width of the DFL sensor;
• and
• depositing insulation layers in contact with the RB and the SAF SB side shields, the insulation layers having a greater stripe height than the RB and the SAF side shields.

A dual free layer (DFL) read head, comprising:

• a DFL sensor disposed at a media facing surface (MFS), the DFL sensor having a first track width;
• synthetic antiferromagnetic (SAF) soft bias (SB) side shields adjacent to the DFL sensor at the MFS, wherein the DFL sensor and the SAF SB side shields collectively have a second track width at the MFS;
• a rear bias disposed adjacent to the DFL sensor recessed from the MFS, the rear bias having a third track width less than the second track width and greater than the first track width, and
• one or more insulation layers disposed in contact with the RB and the SAF SB side shields, the one or more insulation layers having a greater stripe height than the RB and the SAF side shields.