Two-dimensional magnetic recording (TDMR) read head structure with different stacked sensors and disk drive incorporating the structure

A magnetic recording disk drive slider for supporting a read head and a write head to read and write data in tracks of a magnetic recording disk, the slider having a gas-bearing surface (GBS) for facing the disk and a trailing surface substantially orthogonal to the GBS and extending in a generally cross-track direction relative to the tracks of the disk, the slider comprising:

• a first magnetic shield layer on the trailing surface of the slider;
• a dual free layer (DFL) magnetoresistive read head on the first shield layer and having a front edge aligned in the cross-track direction at the GBS, the DFL read head comprising first and second ferromagnetic free layers, a non-magnetic spacer layer between the first and second free layers, soft magnetic bias structures adjacent the first and second free layers in the cross-track direction, each soft magnetic bias structure comprising two side ferromagnetic biasing layers separated by a non-magnetic antiparallel coupling layer for biasing the magnetizations of the first and second free layers substantially in the cross-track direction, and a rear ferromagnetic biasing layer recessed from the GBS for biasing the magnetizations of the first and second free layers to make a non-zero angle relative to one another;
• a first middle magnetic shield on the DFL read head;
• a non-magnetic separation layer on the first middle shield;
• a second middle magnetic shield on the separation layer;
• a single free layer (SFL) magnetoresistive read head on the second middle magnetic shield and having a front edge aligned in the cross-track direction at the GBS, the SFL read head being substantially aligned with the DFL read head in an along-the-track direction orthogonal to the cross-track direction so as to read data from the same track as the DFL read head, the SFL read head comprising a ferromagnetic free layer having a magnetization oriented generally parallel to said SFL sensor front edge, a pinned ferromagnetic layer having a magnetization oriented generally orthogonal to the GBS, a non-magnetic spacer layer between the free and pinned layers, and ferromagnetic biasing layers adjacent the single free layer in the cross-track direction for biasing the magnetization of the single free layer substantially in the cross-track direction;
• and
• a second magnetic shield on the SFL read head.