Patent ID: 7889457

Claim:
A perpendicular magnetic recording head device composed of a main magnetic pole layer and a return path layer which are laminated with a nonmagnetic insulating layer therebetween and having a laminated structure including a proximity region where the main magnetic pole layer and the return path layer are in proximity to each other on a recording medium-facing surface, wherein the return path layer includes a low saturation magnetic flux density layer made of a material that has a relatively low saturation magnetic flux density to prevent a magnetic flux from intruding into the return path layer from the main magnetic pole layer, at least on the side of the main magnetic pole layer, and wherein the spacing between the main magnetic pole layer and the return path layer in the proximity region is about 50 nm, and the thickness of the low saturation magnetic flux density layer on the side of the main magnetic pole layer is about 10 nm to about 100 nm.