# US 2019/0378974 A1 · Magnetoresistance effect element

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- Number: US 2019/0378974 A1
- Document ID: US20190378974A1
- Status: Published application
- Kind: A1
- Application number: 16/542,462
- Filed: 2019-08-16
- Published: 2019-12-12
- Earliest claimed: 2015-03-31
- Assignees: TDK Corporation
- Applicants: TDK Corporation
- Inventors: Tomoyuki SASAKI; Katsuyuki NAKADA; Tatsuo SHIBATA
- Web page: https://patentgrep.com/patent/US20190378974A1

## CPC

- H10N 50/85: Materials of the active region
- G01R 33/093: {using multilayer structures, e.g. giant magnetoresistance sensors (thin magnetic films H01F10/00)}
- G01R 33/098: {comprising tunnel junctions, e.g. tunnel magnetoresistance sensors}
- G11B 5/3909: {Arrangements using a magnetic tunnel junction}
- G11C 11/161: {details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell}
- G11C 11/1675: {Writing or programming circuits or methods}
- H10B 61/00: Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
- H10D 48/40: Devices controlled by magnetic fields
- H10N 50/10: Magnetoresistive devices
- H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)
- G11C: STATIC STORES (semiconductor memory devices H10B)
- H10B: ELECTRONIC MEMORY DEVICES
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES

## Abstract

A magnetoresistance effect element has a first ferromagnetic metal layer, a second ferromagnetic metal layer, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, and the tunnel barrier layer has a spinel structure represented by a composition formula of AIn2Ox(0<x≤4), and an A-site is a non-magnetic divalent cation which is one or more selected from a group consisting of magnesium, zinc and cadmium.

## Claims

### Claim 1

A magnetoresistance effect element comprising:
a first ferromagnetic metal layer;
a second ferromagnetic metal layer; and
a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers,
wherein the tunnel barrier layer has a spinel structure comprising a divalent cation and a trivalent cation in a unit cell wherein a concentration of constituent elements of the divalent cation in the unit cell is more than half a concentration of constituent elements of the trivalent cation in the unit cell, and
wherein the divalent cation is a non-magnetic divalent cation which is one or more selected from a group consisting of magnesium, zinc and cadmium,
wherein the tunnel barrier layer comprises: at least one lattice-matched portion that is lattice-matched with both of the first ferromagnetic metal layer and the second ferromagnetic metal layer; and at least one lattice-mismatched portion that is not lattice-matched with at least one of the first ferromagnetic metal layer and the second ferromagnetic metal layer.

### Claim 2 (depends on 1)

The magnetoresistance effect element according to claim 1,
wherein a volume ratio of the lattice-matched portion with respect to a volume of the entire tunnel barrier layer is 65% to 95%.

### Claim 3 (depends on 1)

The magnetoresistance effect element according to claim 1, wherein the tunnel barrier layer has a spinel structure in which an atomic arrangement is disordered.

### Claim 4 (depends on 1)

The magnetoresistance effect element according to claim 1,
wherein the first ferromagnetic metal layer has larger coercivity than that of the second ferromagnetic metal layer.

### Claim 5 (depends on 1)

The magnetoresistance effect element according to claim 1,
wherein the tunnel barrier layer has a film thickness of 0.7 nm to 1.7 nm.

### Claim 6 (depends on 1)

The magnetoresistance effect element according to claim 1,
wherein at least one of the first ferromagnetic metal layer and the second ferromagnetic metal layer has magnetic anisotropy perpendicular to a stacking direction.

### Claim 7 (depends on 1)

The magnetoresistance effect element according to claim 1,
wherein at least one of the first ferromagnetic metal layer and the second ferromagnetic metal layer is Co2Mn1-aFeaAlbSi1-b (0≤a≤1, 0≤b≤1).