CPP-type magnetic head with less deformation and a magnetic recording/reproducing system using the same

A magnetic head comprising:

• a lower shield layer;
• an upper shield layer;
• a magnetoresistive film formed between the upper shield layer and the lower shield layer and comprising at least a first ferromagnetic layer, an intermediate layer and a second ferromagnetic layer;
• a lower gap layer formed between the lower shield layer and the magnetoresistive film;
• and an upper gap layer formed between the upper shield layer and the magnetoresistive film, and having detection means for detecting a resistance change produced from the magnetoresistive film by a variation in an external magnetic field when a sensing current is applied in a direction substantially perpendicular to the interface between the first ferromagnetic layer and the intermediate layer and the interface between the intermediate layer and the second ferromagnetic layer, wherein
• a deformation prevention layer having a higher shear modulus than the first ferromagnetic layer and the second ferromagnetic layer is formed between the magnetoresistive film and at least one of the upper shield layer and the lower shield layer, and
• the deformation prevention layer contains at least one element selected from the group consisting of Mo, Rh, W and Ir and at least one element selected from the group consisting of B, C and N.