Tohoku University

Hiroaki Honjo

Shoji Ikeda

Tetsuo Endoh

Hideo Sato

Hideo Ohno

Masaaki Niwa

Koichi Nishioka

Kenchi Ito

Shunsuke Fukami

Fumihiro Matsukura

Sadahiko Miura

Soshi Sato

Kyota Watanabe

Tetsuo Endo

Mathias Bersweiler

Yoshihisa Horikawa

Toshinari Watanabe

A magnetoresistance effect element includes a first reference layer, a first junction layer, a first divided recording layer, a second junction layer, a second divided recording layer, and a third junction layer. The first divided recording layer has a configuration having a high magnetoresistance ratio (MR ratio), and the second divided recording layer (3) has a configuration having a high effective magnetic anisotropy energy density (Kt).

Magnetoresistance effect element, magnetic memory, and film formation method for said magnetoresistance effect element

Provided are a magnetic tunnel junction dement suppressing diffusion and penetration of constituent elements between a hard mask film, and a magnetic tunnel junction film and a protection layer, and a method for manufacturing the magnetic tunnel junction element. The magnetic tunnel junction element has a configuration in which a non-magnetic insertion layer () including Ta or the like is inserted beneath a hard mask layer ().

Magnetic tunnel junction device, method for manufacturing magnetic tunnel junction device, and magnetic memory

Provided are a magnetoresistance effect element and a magnetic memory having a shape magnetic anisotropy and using a recording layer having an anti-parallel coupling. A first magnetic layer () and a second magnetic layer () of the magnetoresistance effect element include a ferromagnetic substance, have a magnetization direction variable to the direction perpendicular to a film surface and are magnetically coupled in an anti-parallel direction, and a junction size D (nm), which is a length of the longest straight line on an end face perpendicular to the thickness direction of the first magnetic layer () and the second magnetic layer (), a film thickness t(nm) of the first magnetic layer (), and a film thickness t(nm) of the second magnetic layer () satisfy relationships D&#x3c;tand D&#x2264;tor D&#x2264;tand D&#x3c;t.

Magnetoresistive element and magnetic memory

A magnetoresistance effect element with a small element size can be provided which achieves both an increase in a thermal stability factor &#x394; and a reduction in a writing current Iand which improves a performance index &#x394;/I(&#x3bc;A) obtained by dividing the thermal stability factor &#x394; by the writing current I. The magnetoresistance effect element includes a first reference layer (B), a first junction layer (), a first magnetic layer (), a first non-magnetic coupling layer (), a second magnetic layer (), and a second junction layer (), and a film thickness of the first non-magnetic coupling layer () is 0.1 nm or more and 0.3 nm or less.

Magnetoresistance effect element and magnetic memory

A magnetic tunnel junction element () includes a configuration in which a reference layer () that includes a ferromagnetic material, a barrier layer () that includes O, a recording layer () that includes a ferromagnetic material including Co or Fe, a first protective layer () that includes O, and a second protective layer () that includes at least one of Pt, Ru, Co, Fe, CoB, FeB, or CoFeB are layered.

Magnetic tunnel junction element and magnetic memory

Provided is a magnetoresistance effect element in which the magnetization direction of the recording layer is perpendicular to the film surface and which has a high thermal stability factor &#x394;, and a magnetic memory. A recording layer having a configuration of first magnetic layer/first non-magnetic coupling layer/first magnetic insertion layer/second non-magnetic coupling layer/second magnetic layer is sandwiched between the first and second non-magnetic layers and stacked so that a magnetic coupling force is generated between the first magnetic layer and the second magnetic layer.

An object of the invention is to provide a magnetoresistance effect element which includes a reference layer having three or more magnetic layers and which improves a thermal stability factor &#x394; by decreasing a write error rate using an element structure that enables a wide margin to be secured between a current at which magnetization of the reference layer is reversed and a writing current Ic of a recording layer and by reducing an effect of a stray magnetic field from the reference layer. The magnetoresistance effect element includes: a first recording layer (A); a first non-magnetic layer (); and a first reference layer (B), wherein the first reference layer (B) including n-number of a plurality of magnetic layers () and (n&#x2212;1)&#x2212;number of a plurality of non-magnetic insertion layers ((n&#x2212;1)) adjacently sandwiched by each of the plurality of magnetic layers, where n&#x2265;3.

Provided are a magnetic memory element in which an improvement in properties, such as an improvement in coercive properties or a reduction in a leak current, can be attained, a method for producing the same, and a magnetic memory. The magnetic memory element, includes: a columnar stack ST in which a reference layer FX having a fixed magnetization direction, a barrier layer TL including a non-magnetic body, and a recording layer FR having a reversible magnetization direction are stacked in this order; and an insulating film which contains nitrogen and is provided to cover a lateral surface of the columnar stack, in which in one or both of the recording layer and the barrier layer, a nitrogen concentration is 7&#xd7;10atoms/mor more in a position of 2 nm inside from an outer circumferential end of the columnar stack.

Magnetic memory element, method for producing same, and magnetic memory

A structure used in the formation of a spintronics element, the spintronics element to include a plurality of laminated layers, includes a substrate, a plurality of laminated layers formed on the substrate, an uppermost layer of the plurality of laminated layers being a non-magnetic layer containing oxygen, and a protection layer directly formed on the uppermost layer, the protection layer preventing alteration of characteristics of the uppermost layer while exposed in an atmosphere including HO, a partial pressure of HO in the atmosphere being equal to or larger than 10Pa, no other layer being directly formed on the protection layer.

Spin electronics element and method of manufacturing thereof

The present invention provides a magnetoresistance effect element which has a high thermal stability factor &#x394; and in which a magnetization direction of a recording layer is a perpendicular direction with respect to a film surface, and a magnetic memory including the same. Magnetic layers of a recording layer of the magnetoresistance effect element are divided into at least two, and an Fe composition with respect to a sum total of atomic fractions of magnetic elements in each magnetic layer is changed before stacking the magnetic layers.

Magnetoresistance effect element, magnetic memory, and method for manufacturing magnetoresistance effect element

A magnetic tunnel junction element includes, in a following stack order, an underlayer formed of a metal material, a fixed layer formed of a ferromagnetic body, a magnetic coupling layer formed of a nonmagnetic body, a reference layer formed of a ferromagnetic body, a barrier layer formed of a nonmagnetic body, and a recording layer formed of a ferromagnetic body, or alternatively, the magnetic tunnel junction element includes, in a following stack order, a recording layer formed of a ferromagnetic body, a barrier layer formed of a nonmagnetic body, a reference layer formed of a ferromagnetic body, a magnetic coupling layer formed of a nonmagnetic body, an underlayer formed of a metal material, and a fixed layer formed of a ferromagnetic body, wherein the fixed layer is formed and stacked after performing plasma treatment to a surface of the underlayer having been formed.

Magnetic tunnel junction element and method for manufacturing same

A magnetic tunnel junction element configured by stacking, in a following stack order, a fixed layer formed of a ferromagnetic body and in which a magnetization direction is fixed, a magnetic coupling layer formed of a nonmagnetic body, a reference layer formed of a ferromagnetic body and in which the magnetization direction is fixed, a barrier layer formed of a nonmagnetic body, and a recording layer formed of a ferromagnetic body, a barrier layer formed of a nonmagnetic body, and a recording layer formed by sandwiching an insertion layer formed of a nonmagnetic body between first and second ferromagnetic layers, wherein the magnetic coupling layer is formed using a sputtering gas in which a value of a ratio in which a mass number of an element used in the magnetic coupling layer divided by the mass number of the sputtering gas itself is 2.2 or smaller.

Method of manufacturing magnetic tunnel coupling element

A magnetoresistance effect element includes first and second magnetic layers having a perpendicular magnetization direction, and a first non-magnetic layer disposed adjacent to the first magnetic layer and on a side opposite to a side on which the second magnetic layer is disposed. An interfacial perpendicular magnetic anisotropy exists at an interface between the first magnetic layer and the first non-magnetic layer, and the anisotropy causes the first magnetic layer to have a magnetization direction perpendicular to the surface of the layers. An atomic fraction of all magnetic elements to all magnetic and non-magnetic elements included in the second magnetic layer is smaller than that of the first magnetic layer.

A method for producing a magnetic memory includes: forming a magnetic film having a non-magnetic layer between a first magnetic layer and a second magnetic layer on a substrate having an electrode layer; performing annealing treatment at a first treatment temperature in a state where a magnetic field is applied in a direction perpendicular to a film surface of the first or the second magnetic layer in vacuum; forming a magnetic tunnel junction element; forming a protective film protecting the magnetic tunnel junction element; a formation accompanied by thermal history, in which a constituent element of a magnetic memory is formed after the protective film formation on the substrate; and implementing annealing treatment at a second treatment temperature lower than the first treatment temperature on the substrate in an annealing treatment chamber, in vacuum or inert gas wherein no magnetic field is applied.

Method for producing magnetic memory comprising magnetic tunnel junction element

A magnetic tunnel junction element with a high tunnel magnetic resistance ratio can prevent a recording layer from being damaged. A reference layer includes a ferromagnetic body, and has magnetization direction fixed in the vertical direction. A barrier layer includes non-magnetic body, and disposed on one surface side of the reference layer. A recording layer is disposed to sandwich barrier layer between itself and reference layer. The recording layer includes a first ferromagnetic layer including at least one of Co and Fe, and having a magnetization direction variable in a vertical direction; a first non-magnetic layer including at least one of Mg, MgO, C, Li, Al, and Si, second non-magnetic layer including at least one of Ta, Hf, W, Mo, Nb, Zr, Y, Sc, Ti, V, and Cr, and second ferromagnetic layer including at least one of Co and Fe, and having a magnetization direction variable in a vertical direction.

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Sendai, Japan

Hiroaki Honjo