Patent ID: 7639451
Filing Date: 2009-12-29
Classification: G11B

Abstract:
1. A thin-film magnetic head comprising a perpendicular recording head portion including a thin-film coil adapted to generate a magnetic flux and a main magnetic pole layer having a main magnetic pole adapted to release a magnetic flux generated at said thin-film coil toward a recording medium, characterized in that: said main magnetic pole includes a front end portion of a narrow width, extending rearward from a recording medium opposite plane and a rear end portion that is coupled to said front end portion and has a width becoming gradually wide toward the rear, a coupling site of said front end portion to said rear end portion defines a boundary surface defined as a flare point, a section of said front end portion with respect to said recording medium opposite plane has an inverted trapezoidal shape wherein, in consideration of relative movement to said recording medium, a short side is defined by a width W there are concave grooves found on both inverted trapezoidal sides of the front end portion along substantially a thickness direction when viewing said both sides in a range of up to 100 nm in front of the boundary surface that is a position of said flare point, wherein a depth of each concave groove (width direction) grows larger as the lower end edge of width W