Magnetic field detecting element including tri-layer stack with stepped portion

A magnetic field detecting element comprising:

• a stack including an upper magnetic layer and a lower magnetic layer, and a non-magnetic intermediate layer sandwiched between said upper magnetic layer and said lower magnetic layer, wherein magnetization of said upper magnetic layer and said lower magnetic layer change in accordance with an external magnetic field;
• an upper shield electrode layer and a lower shield electrode layer which is provided to sandwich said stack therebetween in a direction of the stacking of said stack, wherein said upper shield electrode layer and said lower shield electrode layer supply sense current in the direction of stacking, and magnetically shield said stack;
• a bias magnetic layer which is provided on a surface of said stack opposite to an air bearing surface, and wherein said bias magnetic layer applies a bias magnetic field to said upper magnetic layer and said lower magnetic layer in a direction perpendicular to the air bearing surface;
• and
• insulating layers which are provided on both sides of said stack in a track width direction thereof, wherein
• said stack has a stepped portion formed at said non-magnetic intermediate layer so that a length of said upper magnetic layer in the track width direction is different from that of said lower magnetic layer.