Konica Minolta, Inc.

Tohoku University

Kosuke Fujiwara

Junichi Jono

Yasuo Ando

Mikihiko Oogane

Koujirou Sekine

Masaaki Tsuchida

Provided is a production method for a magnetoresistive element including treating a stacked layer into a predetermined shape. The stacked layer includes a magnetoresistive layer whose resistance changes depending on a magnetic field and a cap layer above the magnetoresistive layer and having a thickness in a range of 10 nm to 60 nm. The method further includes covering and protecting the stacked layer with an insulating layer, forming an opening in the insulating layer by reactive etching and exposing a surface of the cap layer at the opening, etching the cap layer in a range less than a total thickness of the cap layer by ion milling of the surface, and depositing an upper layer to be a part of the magnetoresistive element. The upper layer is in contact with the surface of the cap layer after the etching.

Magnetoresistive element, and production method for magnetoresistive element

A method for producing a tunnel magnetoresistive element includes a stacking step, then in-magnetic field heating, and then dry etching. The stacking includes stacking a B absorption layer which is in contact with an upper surface of a CoFeB layer. The dry etching includes removal of layers to the B absorption layer. An end of etching is set as an end point time detected by an analysis device when a final layer before the B absorption layer directly above the CoFeB layer is exposed has reduced to a prescribed level, or when the B absorption layer directly above the CoFeB layer has increased to the prescribed level. An amount of over-etching after the end point time is specified in advance, and the B absorption layer is stacked such that the thickness from the prescribed level to the upper surface of the CoFeB layer corresponds to the over-etching amount.

Method for producing tunnel magnetoresistive element

A tunnel magnetic resistance element includes the following, a fixed magnetic layer with a fixed direction of magnetization, a free magnetic layer in which the direction of magnetization changes, and an insulating layer which is positioned between the fixed magnetic layer and the free magnetic layer. The fixed magnetic layer, the free magnetic layer, and the insulating layer form a magnetic tunnel junction. A resistance of the insulating layer changes by a tunnel effect according to a difference in an angle between the direction of magnetization of the fixed magnetic layer and the direction of magnetization of the free magnetic layer. The free magnetic layer includes a ferromagnetic layer, a soft magnetic layer, and a magnetic bonding layer placed in between. Material of the magnetic bonding layer include Ru or Ta, and a layer thickness is 1.0 nm to 1.3 nm.

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Sendai, Japan

Kosuke Fujiwara