US 8,009,391 B2Granted

Magnetic sensing element and method for manufacturing the same

AssigneeTDK Corporation

InventorsKenichi Tanaka, Eiji Umetsu, Kazuaki Ikarashi, Kota Asatsuma, Norimasa Okanishi, Yoshihiro Nishiyama, Masamichi Saito, Yosuke Ide, Kazumasa Nishimura, Ryo Nakabayashi, Hidekazu Kobayashi, Akio Hanada, Naoya Hasegawa

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Abstract

An underlying layer is composed of Co—Fe—B that is an amorphous magnetic material. Thus, the upper surface of the underlying layer can be taken as a lower shield layer-side reference position for obtaining a gap length (GL) between upper and lower shields, resulting in a narrower gap than before. In addition, since the underlying layer has an amorphous structure, the underlying layer does not adversely affect the crystalline orientation of individual layers to be formed thereon, and the surface of the underlying layer has good planarizability. Accordingly, PW50 (half-amplitude pulse width) and SN ratio can be improved more than before without causing a decrease in rate of change in resistance (Δ R/R) or the like, thereby achieving a structure suitable for increasing recording density.

Claims21

Dependent claims

A magnetic sensing element comprising a multilayered film with a plurality of layers stacked between opposing lower and upper shield layers that are spaced apart from each other in a film thickness direction,

wherein a maximum width of said multilayered film in a track width direction is smaller than a width of either of said lower and upper shield layers in said track width direction, and at both sides of said multilayered film in said track width direction, a bias layer and an insulating layer constitute a laminated structure filling a space between said lower and upper shield layers,
wherein a bottom layer of said multilayered film is an underlying layer disposed on and in contact with said lower shield layer, a top layer of said multilayered film is a protective layer, said multilayered film further includes at least a pinned magnetic layer, a free magnetic layer, and a nonmagnetic material layer deposited between said underlying layer and said protective layer in said film thickness direction, and said nonmagnetic material layer is disposed between said pinned magnetic layer and said free magnetic layer,
wherein said underlying layer is composed of an amorphous magnetic material.

A method for manufacturing a magnetic sensing element comprising:

(a) forming a lower shield layer;
(b) forming a multilayered film on said lower shield layer, said multilayered film having a plurality of layers deposited continuously in a same vacuum, a bottom layer of said multilayered film being an underlying layer composed of an amorphous magnetic material and disposed on and in contact with said lower shield layer, a top layer of said multilayered film being a protective layer, said multilayered film further including at least a pinned magnetic layer, a free magnetic layer, and a nonmagnetic material layer deposited between said underlying layer and said protective layer in a film thickness direction, said nonmagnetic material layer being disposed between said pinned magnetic layer and said free magnetic layer;
(c) removing both side portions of said multilayered film in a track width direction so that a maximum width of said multilayered film in said track width direction is smaller than a width of said lower shield layer in said track width direction;
(d) forming a laminated structure including a bias layer and an insulating layer to fill a space created by removing said both side portions of said multilayered film;
and
(e) forming an upper shield layer over said multilayered film and said laminated structure at both sides of said multilayered film, said upper shield layer having a larger width than said multilayered film in said track width direction.

3 more elements

Dependencies are inferred from the claim text.