JP2017174910A - Magnetic storage element and nonvolatile storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic storage element and a nonvolatile storage device with high reliability.SOLUTION: A magnetic storage element includes a first magnetic layer, a second magnetic layer, a first non-magnetic layer, and a second non-magnetic layer. The first non-magnetic layer is provided between the first magnetic layer and the second magnetic layer. The magnetization of the first magnetic layer is substantially fixed, and the direction of the magnetization of the second magnetic layer is variable. A first direction is a direction from the first magnetic layer to the second magnetic layer. At least a part of the second non-magnetic layer overlaps with at least a part of the first magnetic layer in a second direction orthogonal to the first direction. The second non-magnetic layer is electrically connected to the first magnetic layer.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a magnetic memory element and a nonvolatile memory device.

  In a magnetic random access memory (MRAM), for example, a ferromagnetic tunnel junction (MTJ) element is used in a data storage unit. In the ferromagnetic tunnel junction, a tunneling magnetoresistive (TMR) effect is obtained. In the magnetic memory element and the nonvolatile memory device, improvement in reliability is desired.

Japanese Patent Application Laid-Open No. 2014-179639

  Embodiments of the present invention provide a highly reliable magnetic memory element and nonvolatile memory device.

  According to the embodiment of the present invention, the magnetic memory element includes a first magnetic layer, a second magnetic layer, a first nonmagnetic layer, and a second nonmagnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer. The first direction is a direction from the first magnetic layer toward the second magnetic layer. At least a part of the second nonmagnetic layer overlaps at least a part of the first magnetic layer in a second direction orthogonal to the first direction. The second nonmagnetic layer is electrically connected to the first magnetic layer. The magnetization of the first magnetic layer is substantially fixed, and the magnetization direction of the second magnetic layer is variable.

FIG. 1A and FIG. 1B are schematic views illustrating the magnetic memory element according to the first embodiment. FIG. 2A to FIG. 2C are schematic views illustrating another magnetic memory element according to the first embodiment. FIG. 3A to FIG. 3C are schematic views illustrating another magnetic memory element according to the first embodiment. FIG. 4A and FIG. 4B are schematic views illustrating simulation results of the magnetic memory element. 3 is a schematic cross section illustrating characteristics of a magnetic memory element. 6 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment. FIG. 6 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment. FIG. 6 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment. FIG. FIG. 6 is a schematic perspective view illustrating another magnetic memory element according to the first embodiment. FIG. 4 is a schematic view illustrating another nonvolatile memory device according to the first embodiment. FIG. 11A and FIG. 11B are schematic views illustrating magnetization. FIG. 12A to FIG. 12D are schematic views illustrating the operation of the nonvolatile memory device according to the first embodiment. FIG. 13A to FIG. 13D are schematic views illustrating the operation of the nonvolatile memory device according to the first embodiment. FIG. 14A and FIG. 14B are schematic views illustrating the operation of the nonvolatile memory device according to the first embodiment. FIG. 15A to FIG. 15F are schematic cross-sectional views illustrating the method for manufacturing the magnetic memory element according to the first embodiment. FIG. 16A to FIG. 16D are schematic cross-sectional views illustrating the method for manufacturing the magnetic memory element according to the first embodiment. FIG. 17A to FIG. 17E are schematic cross-sectional views illustrating another method for manufacturing the magnetic memory element according to the first embodiment. FIG. 18A to FIG. 18D are schematic cross-sectional views illustrating another method for manufacturing the magnetic memory element according to the first embodiment. 3 is a schematic cross-sectional view illustrating another nonvolatile memory device according to the first embodiment. FIG. FIG. 20A to FIG. 20J are schematic cross-sectional views illustrating other magnetic memory elements according to the first embodiment. FIG. 4 is a schematic view illustrating another nonvolatile memory device according to the first embodiment. 6 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment. FIG. 3 is a schematic cross-sectional view illustrating another nonvolatile memory device according to the first embodiment. FIG. FIG. 6 is a schematic view illustrating a nonvolatile memory device according to a second embodiment. FIG. 6 is a schematic view illustrating a nonvolatile memory device according to a second embodiment. FIG. 26A to FIG. 26C are schematic views illustrating the nonvolatile memory device according to the third embodiment.

Each embodiment will be described below with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between the parts, and the like are not necessarily the same as actual ones. Even in the case of representing the same part, the dimensions and ratios may be represented differently depending on the drawings.
In the present specification and drawings, the same elements as those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

(First embodiment)
FIG. 1A and FIG. 1B are schematic views illustrating the magnetic memory element according to the first embodiment.
FIG. 1A is a perspective view. FIG. 1B is a cross-sectional view taken along line A1-A2 of FIG.

  As shown in FIGS. 1A and 1B, the magnetic memory element 110 includes a first magnetic layer 10, a second magnetic layer 20, a first nonmagnetic layer 31, and a second nonmagnetic layer 32. And including. The magnetic memory element 110 further includes a fifth nonmagnetic layer 35 and an eighth magnetic layer 18. The fifth nonmagnetic layer 35 and the eighth magnetic layer 18 may be omitted.

  A direction from the first magnetic layer 10 toward the second magnetic layer 20 is defined as a first direction. The first direction corresponds to the stacking direction SD1 of the first magnetic layer 10, the first nonmagnetic layer 31, and the second magnetic layer 20.

  In the specification of the present application, the state of being stacked includes not only the state of being stacked in direct contact but also the case of being stacked with another element inserted therebetween.

  The first direction is the Z-axis direction. One direction perpendicular to the Z-axis direction is, for example, the X-axis direction. A direction perpendicular to the Z-axis direction and the X-axis direction is taken as a Y-axis direction.

  At least a part of the second nonmagnetic layer 32 overlaps at least a part of the first magnetic layer 10 in the second direction orthogonal to the first direction. The second nonmagnetic layer 32 is electrically connected to the first magnetic layer 10. The second direction is one direction (arbitrary direction) in the XY plane. The second nonmagnetic layer 32 may overlap at least a part of the first magnetic layer 10 in a plurality of directions in the XY plane. In this example, the second nonmagnetic layer 32 is provided around the first magnetic layer 10. Hereinafter, the second direction is the X-axis direction.

  For example, in the example shown in FIG. 1A, at least a part of the first magnetic layer 10 is surrounded by the second nonmagnetic layer 32 in the XY plane.

  As shown in FIG. 1B, the first magnetic layer 10 has, for example, a side surface 10w. The side surface 10w intersects a direction (direction in the XY plane) perpendicular to the first direction (Z-axis direction). The second nonmagnetic layer 32 has an inner side surface 32iw. The inner side surface 32iw intersects a direction (direction in the XY plane) perpendicular to the first direction (Z-axis direction).

  The second nonmagnetic layer 32 has an inner side surface (surface) 32iw. In the second direction, at least a part of the inner side surface 32 iw of the second nonmagnetic layer 32 overlaps at least a part of the side surface 10 w of the first magnetic layer 10. For example, in the second direction, the inner side surface 32iw faces the side surface 10w. The inner side surface 32iw may contact the side surface 10w. The second nonmagnetic layer 32 is provided around at least a part of the first magnetic layer 10 in the XY plane. For example, a part of the second nonmagnetic layer 32 may be divided in the XY plane.

  The perpendicular magnetization component along the first direction (Z-axis direction) of the magnetization 10m of the first magnetic layer 10 is larger than the in-plane magnetization component in the direction intersecting the first direction of the magnetization 10m of the first magnetic layer 10. The direction of the magnetization 10m of the first magnetic layer 10 is non-parallel to the surface 10s (for example, the main surface). For example, during normal operation (for example, during writing), the magnetization direction along the first direction of the magnetization 10m of the first magnetic layer 10 does not substantially change. The direction of the magnetization 10m is substantially perpendicular to the surface 10s of the first magnetic layer 10, for example. The first magnetic layer 10 overlaps the eighth magnetic layer 18 and the fifth nonmagnetic layer 35 in the first direction. The first direction has, for example, a component perpendicular to the surface 10s. The first magnetic layer 10 is, for example, a reference layer.

  The second magnetic layer 20 overlaps the first magnetic layer 10 in the Z-axis direction. The second magnetic layer 20 is separated from the first magnetic layer 10 in the Z-axis direction. The direction of the magnetization 20m of the second magnetic layer 20 is variable. For example, an alloy is used for the second magnetic layer 20. The second magnetic layer 20 is, for example, a storage layer.

  The direction of the magnetization 20 m of the second magnetic layer 20 is easier to move than the direction of the magnetization 10 m of the first magnetic layer 10. The direction of the magnetization 20m of the second magnetic layer 20 changes according to stored information. That is, the direction of the magnetization 20m corresponds to the stored information. On the other hand, the direction of the magnetization 10 m of the first magnetic layer 10 is relatively difficult to move as compared to the direction of the magnetization 20 m of the second magnetic layer 20. The direction of the magnetization 10m of the first magnetic layer 10 is substantially fixed, for example, during normal operation (for example, during writing). It is assumed that “the direction of magnetization is substantially fixed” when the direction of magnetization is hard to move compared to the direction of magnetization of the storage layer.

  The first nonmagnetic layer 31 overlaps the first magnetic layer 10 and the second magnetic layer 20 in the Z-axis direction. The first nonmagnetic layer 31 is provided between the first magnetic layer 10 and the second magnetic layer 20. For example, the first nonmagnetic layer 31 is in contact with the first magnetic layer 10 and the second magnetic layer 20. The first magnetic layer 10, the first nonmagnetic layer 31, and the second magnetic layer 20 are stacked in the stacking direction SD1.

  The second nonmagnetic layer 32 does not overlap the second magnetic layer 20 in the second direction (X-axis direction).

  For example, the second nonmagnetic layer 32 is in contact with the first magnetic layer 10. The second nonmagnetic layer 32 may overlap at least part of the first magnetic layer 10 in the Y-axis direction. The second nonmagnetic layer 32 includes at least one selected from the group consisting of Ti, V, Nb, Mo, Ru, Pd, Ta, W, and Pt. The second nonmagnetic layer 32 is, for example, a high spin pumping layer.

  “Spin pumping” is a phenomenon in which, for example, when a different substance b is in contact with a certain magnetic substance a, a damping constant, which is a relaxation term for the precession of magnetization of the magnetic substance a, is effectively increased. In the present embodiment, a layer having a large effect of spin pumping is referred to as a “high spin pumping layer”.

  When the magnetic memory element 110 is cut along the A1-A2 line shown in FIG. 1A, as shown in FIG. 1B, the second nonmagnetic layer 32 includes a first partial region 32a and a second partial region. 32b. The first partial region 32a overlaps with the second partial region 32b in the second direction (X-axis direction). The first partial region 32a overlaps at least a part of the first magnetic layer 10 in the second direction (X-axis direction). The second partial region 32b overlaps at least part of the first magnetic layer 10 in the second direction (X-axis direction). At least a part of the first magnetic layer 10 is provided between the first partial region 32a and the second partial region 32b.

  The distance between the second nonmagnetic layer 32 and the first magnetic layer 10 in the second direction (X-axis direction) is, for example, the length 10L (thickness) of the first magnetic layer 10 in the second direction (X-axis direction). It may be less than half of the above. The distance between the second nonmagnetic layer 32 and the first magnetic layer 10 in the second direction is, for example, the distance between the first partial region 32a and the first magnetic layer 10 in the second direction. The distance between the second nonmagnetic layer 32 and the first magnetic layer 10 in the second direction may be, for example, the distance in the second direction between the second partial region 32 b and the first magnetic layer 10.

  In FIGS. 1A and 1B, a single magnetic memory element 110 is displayed. As will be described later (FIG. 24), the magnetic memory elements 110 are arranged in an array in the XY plane, for example. For example, the distance between the second nonmagnetic layer 32 (the first partial region 32a or the second partial region 32b) and the first magnetic layer 10 in the second direction (X-axis direction) is the second direction (X-axis direction). ) Is less than half of the distance between adjacent magnetic memory elements 110.

  The eighth magnetic layer 18 overlaps the first magnetic layer 10 in the Z-axis direction. The perpendicular magnetization component along the Z-axis direction of the magnetization 18m of the eighth magnetic layer 18 is larger than the in-plane magnetization component in the direction intersecting the Z-axis direction of the magnetization 18m of the eighth magnetic layer 18. The direction of the magnetization 18m of the eighth magnetic layer 18 is non-parallel to the main surface 18s. The direction of the magnetization 18m of the eighth magnetic layer 18 is substantially perpendicular to the main surface 18s of the eighth magnetic layer 18, for example. In this example, the direction of magnetization 18m is opposite to the direction of magnetization 10m. Thereby, at the position of the second magnetic layer 20 (memory layer), the magnetic field of the first magnetic layer 10 in the Z-axis direction is canceled by the magnetic field of the eighth magnetic layer 18 in the Z-axis direction. The eighth magnetic layer 18 is, for example, a shift correction layer. The direction of the magnetization 18m of the eighth magnetic layer 18 is relatively difficult to move as compared to the direction of the magnetization 20m of the second magnetic layer 20. The direction of the magnetization 18m of the eighth magnetic layer 18 is substantially fixed, for example.

  The fifth nonmagnetic layer 35 is provided between the eighth magnetic layer 18 and the first magnetic layer 10. For example, the fifth nonmagnetic layer 35 is in contact with the eighth magnetic layer 18 and the first magnetic layer 10.

  The second nonmagnetic layer 32 overlaps at least part of the eighth magnetic layer 18 in the second direction (X-axis direction). The second nonmagnetic layer 32 is electrically connected to the eighth magnetic layer 18. For example, the second nonmagnetic layer 32 is in contact with the eighth magnetic layer 18. The second nonmagnetic layer 32 may overlap at least part of the eighth magnetic layer 18 in the Y-axis direction.

FIG. 2A to FIG. 2C are schematic views illustrating another magnetic memory element according to the first embodiment.
FIG. 2A is a perspective view. FIG. 2B is a cross-sectional view taken along line A1-A2 of FIG. FIG. 2C is a cross-sectional view taken along line B1-B2 of FIG.

  As shown in FIG. 2A, the magnetic memory element 111A further includes a third magnetic layer 30 and a third nonmagnetic layer 33.

  In the magnetic memory element 111A, the first magnetic layer 10, the fifth nonmagnetic layer 35, the eighth magnetic layer 18, and the second nonmagnetic layer 32 extend in the third direction. The third direction intersects the first direction (Z-axis direction) and the second direction (X-axis direction). The third direction is, for example, the Y-axis direction. The length Ly of the second nonmagnetic layer 32 in the third direction (Y-axis direction) is longer than the length Lx of the second nonmagnetic layer 32 in the second direction (X-axis direction). For example, at least a part of the first magnetic layer 10 is surrounded by the second nonmagnetic layer 32 in the XY plane.

  The third magnetic layer 30 is provided apart from the second magnetic layer 20 in the third direction (Y-axis direction). The third magnetic layer 30 is aligned with the second magnetic layer 20 in the third direction (Y-axis direction). The third magnetic layer 30 is provided apart from the first magnetic layer 10 in the Z-axis direction. The third magnetic layer 30 overlaps part of the first magnetic layer 10 in the Z-axis direction. The third magnetic layer 30 is separated from the first magnetic layer 10 in the Z-axis direction. The direction of the magnetization 30m of the third magnetic layer 30 is variable. The second nonmagnetic layer 32 does not overlap the third magnetic layer 30 in the second direction (X-axis direction). For example, an alloy is used for the third magnetic layer 30. The third magnetic layer 30 is, for example, a storage layer. The number of third magnetic layers 30 is not limited to the number shown.

  The third nonmagnetic layer 33 overlaps the third magnetic layer 30 and the first magnetic layer 10 in the Z-axis direction. The third nonmagnetic layer 33 is provided between the third magnetic layer 30 and the first magnetic layer 10. For example, the third nonmagnetic layer 33 is in contact with the third magnetic layer 30 and the first magnetic layer 10.

  As shown in FIG. 2B, the first magnetic layer 10 overlaps the second magnetic layer 20 in the Z-axis direction. The first magnetic layer 10 is provided between the eighth magnetic layer 18 and the second magnetic layer 20 in the Z-axis direction.

  At least a part of the second nonmagnetic layer 32 overlaps the first magnetic layer 10 in the second direction (X-axis direction). For example, in the second direction (X-axis direction), at least a part of the side surface 10 w of the first magnetic layer 10 overlaps with the inner side surface 32 iw of the second nonmagnetic layer 32. In the second direction (X-axis direction), the side surface 10w may contact the inner side surface 32iw.

  As shown in FIG. 2C, the second nonmagnetic layer 32 overlaps the first magnetic layer 10 in the third direction (Y-axis direction). For example, in the third direction (Y-axis direction), the side surface 10 w of the first magnetic layer 10 overlaps with the inner side surface 32 iw of the second nonmagnetic layer 32. In the third direction (Y-axis direction), the side surface 10w may contact the inner side surface 32iw.

  The first magnetic layer 10 extending in the third direction (Y-axis direction) has a region 10 c provided between the eighth magnetic layer 18 and the third magnetic layer 30. The second nonmagnetic layer 32 overlaps at least a part of the region 10c of the first magnetic layer 10 in the X-axis direction and the Y-axis direction (FIGS. 2A and 2C).

FIG. 3A to FIG. 3C are schematic views illustrating another magnetic memory element according to the first embodiment.
FIG. 3B is a cross-sectional view taken along line A1-A2 of FIG. FIG. 3C is a cross-sectional view taken along line B1-B2 of FIG.

  In the magnetic memory element 111B shown in FIG. 3A, the second nonmagnetic layer 32 includes a first partial region 32a and a second partial region 32b. At least the first magnetic layer 10 between the first partial region 32a and the second partial region 32b in a direction (for example, one direction in the XY plane) intersecting the first direction (Z-axis direction). Some are provided. For example, in the second direction (X-axis direction), at least a part of the first magnetic layer 10 is provided between the first partial region 32a and the second partial region 32b.

  The first partial region 32a of the second nonmagnetic layer 32 extends in the third direction (Y-axis direction). The second partial region 32b of the second nonmagnetic layer 32 extends in the third direction (Y-axis direction).

  In the magnetic memory element 111B, the second nonmagnetic layer 32 is discontinuous in the XY plane. For example, a part of the side surface 10w of the first magnetic layer 10 is exposed in the third direction (Y-axis direction).

  As shown in FIG. 3B, in the magnetic memory element 111B, the first magnetic layer 10 is provided between the first partial region 32a and the second partial region 32b in the second direction (X-axis direction). It is done.

  As shown in FIG. 3C, in the magnetic memory element 111B, for example, the side surface 10w of the first magnetic layer 10 is exposed in the third direction (Y-axis direction).

  When writing to the magnetic memory element, a current is passed through the magnetic memory element to reverse the magnetization of the memory layer. At this time, for example, spin transfer torque is used. In this operation, it is desirable that the magnetization of the reference layer is stable. Thereby, for example, desired write efficiency can be ensured. It is desirable that the holding force is large in the reference layer. In the reference layer, it is desirable that a damping constant that is a coefficient of a relaxation term with respect to the magnetization dynamics is large.

  In the magnetic memory element, the resistance value varies depending on whether the magnetization direction of the storage layer and the magnetization direction of the reference layer are parallel or non-parallel. Using this difference in resistance value, “0” or “1” is written and read. When writing to the magnetic memory element, a current flows through the magnetic memory element. For example, “0” or “1” is stored depending on whether a current flows from the storage layer to the reference layer or a current flows from the reference layer to the storage layer.

  The amount of current for reversing the magnetization of the storage layer (write current Iw) is affected by the magnetization of the reference layer in addition to the physical properties of the storage layer. When the magnetization of the reference layer fluctuates due to the flow of current, the writing efficiency to the storage layer decreases. Thereby, for example, the write current may increase.

  The inventor of the present application searched for a condition that the fluctuation of the first magnetic layer 10 (reference layer) becomes small at the time of writing by LLG (Landau Liftshitz Gilbert) simulation. If the fluctuation is attempted to be reduced by optimizing the material of the first magnetic layer 10, the material selection range of the first magnetic layer 10 is narrowed. For example, the combination range of the saturation magnetization Ms of the first magnetic layer 10 and the thickness (length in the SD1 direction) of the first magnetic layer 30 is narrowed. When the fluctuation of the first magnetic layer 10 is large, the write current increases. Along with this, operation inhibition such as reversal of magnetization of the first magnetic layer 10 occurs.

  On the other hand, in the magnetic memory elements 110, 111A, and 111b, the second nonmagnetic layer 32 is provided so as to overlap the first magnetic layer 10 (reference layer) in the X-axis direction. The second nonmagnetic layer 32 includes, for example, a material having a large spin pumping effect. As a result, the effective damping constant of the first magnetic layer 10 increases, and the magnetization fluctuation of the first magnetic layer 10 during writing is suppressed. Thereby, an increase in current during writing is suppressed.

  When the magnetization of the first magnetic layer 10 is stabilized, for example, the length (thickness) of the first magnetic layer 10 in the X-axis direction can be shortened. Thereby, the magnetic memory element can be miniaturized.

  In the magnetic memory elements 111A and 111B, the eighth magnetic layer 18 extends in the third direction (Y-axis direction). Thereby, the leakage magnetic field from the first magnetic layer 10 is easily reduced by the correction magnetic field from the eighth magnetic layer 18. Thereby, a material having a relatively large saturation magnetization can be selected as the material of the first magnetic layer 10.

  For example, when the second nonmagnetic layer 32 overlaps the first magnetic layer 10 in the X-axis direction, the first magnetic layer 10 does not overlap the second nonmagnetic layer 32 when it does not overlap the first magnetic layer 10. The damping constant α is about 10 times.

FIG. 4A and FIG. 4B are schematic views illustrating simulation results of the magnetic memory element.
The horizontal axis of the graph is the write current density J (A / cm ² ). The vertical axis of the graph represents the write probability Pw. “Α” is a damping constant of the first magnetic layer 10 (reference layer). “Ku” is an effective magnetic anisotropy constant of the first magnetic layer 10 (reference layer). In the graph, the current density when the vertical axis changes from 0 to 1 corresponds to the write current.

  For example, as shown in FIG. 4A, when α is 0.01 and the Ku is 6 or more, the write current is kept at a low value. However, when Ku becomes 5 or less, the write current increases.

  On the other hand, as shown in FIG. 4B, when α is 1, the writing current is kept at a low value in the range of Ku from 1 to 9. As a result, when the effective damping constant of the first magnetic layer 10 increases, an increase in write current is suppressed.

FIG. 5 is a schematic cross-sectional view illustrating characteristics of the magnetic memory element.
As shown in FIG. 5, when the second nonmagnetic layer 32 contacts the first magnetic layer 10, the magnetization of the portion 10 d where the second nonmagnetic layer 32 contacts the first magnetic layer 10 decreases. This is because, for example, a mixed layer of the second nonmagnetic layer 32 and the first magnetic layer 10 is generated. Thereby, the magnetic force leaking from the first magnetic layer 10 of the magnetic memory element 110 is reduced. Thereby, for example, malfunction of the magnetic memory element located beside the magnetic memory element 110 is suppressed.

FIG. 6 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment.
In the magnetic memory element 112 shown in FIG. 6, the length 20L of the second magnetic layer 20 in the second direction (X-axis direction) is longer than the length 10L of the first magnetic layer 10 in the second direction (X-axis direction). Also short. The cross-sectional area of the first magnetic layer 10 when cut along the XY plane is larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The cross-sectional area of the first nonmagnetic layer 31 when cut along the XY plane is larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The cross-sectional area of the eighth magnetic layer 18 when cut along the XY plane is larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The cross-sectional area of the first nonmagnetic layer 31 when cut along the XY plane may be smaller than the cross-sectional area of the first magnetic layer 10 when cut along the XY plane.

  In the manufacturing process of the magnetic memory element 112, the eighth magnetic layer 18, the fifth nonmagnetic layer 35, the first magnetic layer 10, the first nonmagnetic layer 31, and the second magnetic layer 20 are formed in advance. The eighth magnetic layer 18, the fifth nonmagnetic layer 35, the first magnetic layer 10, and the first nonmagnetic layer 31 are patterned. At this time, for example, the length of the second magnetic layer 20 in the X-axis direction is the same as the length of the first magnetic layer 10 in the X-axis direction. Thereafter, the second nonmagnetic layer 32 is formed, and the second magnetic layer 20 is patterned again. The length of the second magnetic layer 20 in the X-axis direction is processed so as to be shorter than the length of the first magnetic layer 10 in the X-axis direction. This makes it difficult for the second nonmagnetic layer 32 to be redeposited on the side surface of the second magnetic layer 20.

FIG. 7 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment.
The magnetic memory element 113 shown in FIG. 7 further includes a fourth magnetic layer 40 and a fifth magnetic layer 50.

  The fourth magnetic layer 40 overlaps the first nonmagnetic layer 31 and the second magnetic layer 20 in the Z-axis direction. The fourth magnetic layer 40 is provided between the first nonmagnetic layer 31 and the second magnetic layer 20 in the Z-axis direction. The direction of the magnetization 40m of the fourth magnetic layer 40 is variable. For example, an alloy is used for the fourth magnetic layer 40. The fourth magnetic layer 40 is, for example, another storage layer. In the magnetic memory element 113, the memory layer includes the second magnetic layer 20 and the fourth magnetic layer 40. The storage layer has, for example, a two-layer structure.

  The fifth magnetic layer 50 overlaps the first nonmagnetic layer 31 and the first magnetic layer 10 in the Z-axis direction. The fifth magnetic layer 50 is provided between the first nonmagnetic layer 31 and the first magnetic layer 10 in the Z-axis direction. The perpendicular magnetization component along the Z-axis direction of the magnetization 50m of the fifth magnetic layer 50 is larger than the in-plane magnetization component in the direction intersecting the Z-axis direction of the magnetization 50m of the fifth magnetic layer 50. The direction of the magnetization 50m of the fifth magnetic layer 50 is non-parallel to the main surface 50s. The direction of the magnetization 50m of the fifth magnetic layer 50 is substantially perpendicular to the main surface 50s of the fifth magnetic layer 50, for example. The fifth magnetic layer 50 is, for example, another reference layer. In the magnetic memory element 113, the reference layer includes the first magnetic layer 10 and the fifth magnetic layer 50. The reference layer has, for example, a two-layer structure. One of the first magnetic layer 10 and the fifth magnetic layer 50 may be removed. The direction of the magnetization 50m of the fifth magnetic layer 50 is relatively difficult to move as compared to the direction of the magnetization 20m of the second magnetic layer 20. The direction of the magnetization 50m of the fifth magnetic layer 50 is substantially fixed.

  The direction of the magnetization 10 m of the first magnetic layer 10 may be a direction from the first magnetic layer 10 toward the second magnetic layer 20. The direction of the magnetization 10 m of the first magnetic layer 10 may be a direction from the second magnetic layer 20 toward the first magnetic layer 10. The magnetization direction of the first magnetic layer 10 may be the same as or opposite to the magnetization direction of the fifth magnetic layer 50.

  In the X-axis direction, the second nonmagnetic layer 32 overlaps at least a part of the fifth magnetic layer 50. The second nonmagnetic layer is electrically connected to the fifth magnetic layer 50. For example, the second nonmagnetic layer 32 contacts the fifth magnetic layer 50.

  For example, the distance between the second nonmagnetic layer 32 (the first partial region 32a or the second partial region 32b) and the fifth magnetic layer 50 in the X-axis direction is the length of the fifth magnetic layer 50 in the X-axis direction. It may be less than half of (thickness). In FIG. 7, a single magnetic memory element 113 is displayed. As will be described later (FIG. 24), the magnetic memory elements 113 are arranged in an array in the XY plane, for example. For example, the distance between the second nonmagnetic layer 32 (the first partial region 32a or the second partial region 32b) and the fifth magnetic layer 50 in the X axis direction is between the magnetic memory elements 113 adjacent in the X axis direction. Less than half of the distance.

  In the magnetic memory element 113, the exchange coupling force between the second magnetic layer 20 and the fourth magnetic layer 40 can be adjusted. Thereby, for example, retention reduction is suppressed. Or, for example, the write current is reduced. Alternatively, for example, interference with adjacent magnetic memory elements is suppressed.

  In the magnetic memory element 113, the saturation magnetization of the second magnetic layer 20 is adjusted. The saturation magnetization of the fourth magnetic layer 40 is adjusted. Thereby, for example, retention reduction is suppressed. Or, for example, the write current is reduced. Alternatively, for example, interference with adjacent magnetic memory elements is suppressed.

  In the magnetic memory element 113, the exchange coupling force between the first magnetic layer 10 and the fifth magnetic layer 50 is adjusted. Thereby, for example, retention reduction is suppressed. For example, interference with adjacent magnetic memory elements is suppressed.

  In the magnetic memory element 113, the saturation magnetization of the first magnetic layer 10 is adjusted. The saturation magnetization of the fifth magnetic layer 50 is adjusted. Thereby, for example, retention reduction is suppressed. For example, interference with adjacent magnetic memory elements is suppressed.

  The cross-sectional area of the first magnetic layer 10 when cut along the XY plane may be larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The cross-sectional area of the first nonmagnetic layer 31 when cut along the XY plane may be larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The cross-sectional area of the eighth magnetic layer 18 when cut along the XY plane may be larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane.

  In the magnetic memory element 113, the third magnetic layer 30 aligned with the second magnetic layer 20 in the third direction (Y-axis direction) may be provided.

FIG. 8 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment.
In the magnetic memory element 114 shown in FIG. 8, the second nonmagnetic layer 32 overlaps at least a part of the fifth magnetic layer 50 in the second direction (X-axis direction). The second nonmagnetic layer is electrically connected to the fifth magnetic layer 50. For example, the second nonmagnetic layer 32 contacts the fifth magnetic layer 50.

  The cross-sectional area of the eighth magnetic layer 18 when cut along the XY plane is larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane. The second nonmagnetic layer 32 does not overlap the eighth magnetic layer 18 in the X-axis direction. The cross-sectional area of the first magnetic layer 10 when cut along the XY plane may be larger than the cross-sectional area of the second magnetic layer 20 when cut along the XY plane.

  In the magnetic memory element 114, an insulating film that overlaps the first magnetic layer 10 and the eighth magnetic layer 18 in the X-axis direction may be provided.

  In the magnetic memory element 114, the second nonmagnetic layer 32 may overlap at least part of the first magnetic layer 10 in the X-axis direction. The second nonmagnetic layer 32 may overlap at least part of the fifth magnetic layer 50 in the X-axis direction. The second nonmagnetic layer 32 may overlap at least part of the first nonmagnetic layer 31 in the X-axis direction.

  It is desirable that the second nonmagnetic layer 32 does not overlap the fourth magnetic layer 40 in the X-axis direction. It is desirable that the second nonmagnetic layer 32 does not overlap the second magnetic layer 20 in the X-axis direction.

FIG. 9 is a schematic perspective view illustrating another magnetic memory element according to the first embodiment.
In the magnetic memory element 115 shown in FIG. 9, the third magnetic layer 30 is aligned with the second magnetic layer 20 in the third direction (Y-axis direction). The first nonmagnetic layer 31 includes a region 31 a provided between the third magnetic layer 30 and the first magnetic layer 10. The first nonmagnetic layer 31 is provided on the first magnetic layer 10 and the second nonmagnetic layer 32.

FIG. 10 is a schematic view illustrating another nonvolatile memory device according to the first embodiment.
The nonvolatile memory device 610 includes a magnetic memory element 110, a magnetic memory element 116, a control unit 550, and a sixth nonmagnetic layer 36. The magnetic memory element 116 includes a stacked body SB0. The stacked body SB0 includes a first stacked unit SB1 and a second stacked unit SB2. The first stacked unit SB1 includes the magnetic memory element 110. The second stacked unit SB2 includes a magnetic memory element 116. A sixth nonmagnetic layer 36 is provided between the first stacked unit SB1 and the second stacked unit SB2.

  Control unit 550 is electrically connected to stacked body SB0. The control unit 550 controls the operation of the stacked body SB0 by applying voltage and supplying current to the stacked body SB0. In FIG. 10, the eighth magnetic layer 18 and the fifth nonmagnetic layer 35 are not displayed. The magnetic memory element 116 may be provided with the eighth magnetic layer 18 and the fifth nonmagnetic layer 35.

  The second stacked unit SB2 overlaps the first stacked unit SB1 in the Z-axis direction. The second stacked unit SB2 includes a sixth magnetic layer 60. The sixth magnetic layer 60 is stacked with the first stacked unit SB1 in the Z-axis direction. The direction of magnetization of the sixth magnetic layer 60 is variable. The width of the sixth magnetic layer 60 (the length in the direction perpendicular to the Z-axis direction) is, for example, 35 nanometers (nm) or less. For example, when the shape of the sixth magnetic layer 60 when projected onto the XY plane is a circle, the diameter of the circle is 35 nm or less. For example, the maximum length in the in-plane direction (direction perpendicular to the Z-axis direction) of the sixth magnetic layer 60 is 35 nm or less. The thickness (length in the Z-axis direction) of the sixth magnetic layer 60 is, for example, not less than 0.5 nm and not more than 3.5 nm.

  In this example, the second stacked unit SB2 further includes a seventh magnetic layer 70 and a fourth nonmagnetic layer 34. The seventh magnetic layer 70 overlaps the sixth magnetic layer 60 in the Z-axis direction. The perpendicular magnetization component along the Z-axis direction of the magnetization 70m of the seventh magnetic layer 70 is larger than the in-plane magnetization component in the direction intersecting the Z-axis direction of the magnetization 70m of the seventh magnetic layer 70. For example, the magnetization direction of the seventh magnetic layer 70 is opposite to the magnetization direction of the first magnetic layer 10. The direction of the magnetization 70m of the seventh magnetic layer 70 is relatively difficult to move as compared to the direction of the magnetization 20m of the second magnetic layer 20. The direction of the magnetization 70m of the seventh magnetic layer 70 is substantially fixed. The fourth nonmagnetic layer 34 overlaps the seventh magnetic layer 70 and the sixth magnetic layer 60 in the Z-axis direction. The fourth nonmagnetic layer 34 is provided between the seventh magnetic layer 70 and the sixth magnetic layer 60. For example, the fourth nonmagnetic layer 34 is in contact with the seventh magnetic layer 70 and the sixth magnetic layer 60.

  In this example, the stacked body SB0 further includes a sixth nonmagnetic layer 36. The sixth nonmagnetic layer 36 is provided between the first stacked unit SB1 and the second stacked unit SB2. In this example, the first magnetic layer 10, the first nonmagnetic layer 31, the second magnetic layer 20, the sixth nonmagnetic layer 36, the sixth magnetic layer 60, the fourth nonmagnetic layer 34, and the seventh magnetic layer 70 are: They are stacked in this order. In the X-axis direction, the second nonmagnetic layer 32 overlaps at least part of the first magnetic layer 10. The sixth nonmagnetic layer 36 is, for example, a spin disappearance layer. Thereby, the spin polarization degree of the electrons flowing through the sixth nonmagnetic layer 36 is easily lost. For example, the sixth nonmagnetic layer 36 is in contact with the first stacked unit SB1 and the second stacked unit SB2. In this example, the sixth nonmagnetic layer 36 is in contact with the second magnetic layer 20 and the sixth magnetic layer 60.

  In this example, the magnetic memory element 110 includes a first conductive layer 81, and the magnetic memory element 116 includes a second conductive layer 82. The first stacked unit SB1 is disposed between the first conductive layer 81 and the second conductive layer 82. The second stacked unit SB2 is disposed between the first stacked unit SB1 and the second conductive layer 82. The first conductive layer 81 is electrically connected to the first stacked unit SB1. In this example, the first conductive layer 81 is electrically connected to the first magnetic layer 10. The second conductive layer 82 is electrically connected to the second stacked unit SB2. In this example, the second conductive layer 82 is electrically connected to the seventh magnetic layer 70.

  The first conductive layer 81 and the second conductive layer 82 are electrically connected to the control unit 550. The stacked body SB0 is directly or indirectly connected to the control unit 550 through the first conductive layer 81 and the second conductive layer 82. The first conductive layer 81 may be regarded as separate from the magnetic memory element 110. The second conductive layer 82 may be regarded as separate from the magnetic memory element 116.

  The nonvolatile memory device 610 further includes, for example, a first wiring 91 and a second wiring 92 (see FIG. 25). For example, the first wiring 91 is electrically connected to the first conductive layer 81. The second wiring 92 is electrically connected to the second conductive layer 82, for example. The control unit 550 is electrically connected to the stacked body SB0 via, for example, the first wiring 91 and the second wiring 92.

  Hereinafter, an example of the configuration and operation of the stacked body SB0 (the magnetic memory element 110 and the magnetic memory element 116) will be described. In addition to the magnetic memory element 110 and the magnetic memory element 116, the following description can be applied to other magnetic memory elements described later according to the embodiment.

  In the stacked body SB0, a current (write current) is passed through the first stacked unit SB1 and the second stacked unit SB2 in the Z-axis direction. Thereby, spin-polarized electrons act on the second magnetic layer 20. In the stacked body SB0, a rotating magnetic field generated by precessing the magnetization of the sixth magnetic layer 60 is applied to the second magnetic layer 20. Thereby, the direction of the magnetization 20m of the second magnetic layer 20 is determined as a direction corresponding to the direction of the current.

  The first magnetic layer 10 functions as, for example, a first magnetization fixed layer. In the first magnetic layer 10, for example, the magnetization 10m is oriented in a direction substantially perpendicular to the film surface. The magnetization 10 m is directed in a direction having a component in the Z-axis direction that connects the first magnetic layer 10 and the second magnetic layer 20. The direction of the magnetization 10m of the first magnetic layer 10 is, for example, substantially parallel to the Z-axis direction.

  In the second magnetic layer 20, for example, the easy axis of magnetization is substantially perpendicular to the film surface. For example, the magnetization direction of the second magnetic layer 20 is substantially perpendicular to the film surface. The magnetization of the second magnetic layer 20 can be reversed relatively easily and is variable in the Z-axis direction. The second magnetic layer 20 has a role of storing data. For example, the second magnetic layer 20 functions as a magnetic storage layer.

  The first nonmagnetic layer 31 functions as a first spacer layer. When the first nonmagnetic layer 31 is a tunnel barrier layer based on an insulating material, the first stacked unit SB1 including the first magnetic layer 10, the first nonmagnetic layer 31, and the second magnetic layer 20 is, for example, MTJ ( Magnetic Tunnel Junction).

  In the sixth magnetic layer 60, for example, the magnetization component projected in the Z-axis direction is smaller than the magnetization component projected in the direction perpendicular to the Z-axis direction. The easy axis of magnetization of the sixth magnetic layer 60 is substantially parallel to the film surface. The magnetization of the sixth magnetic layer 60 is variable in a direction perpendicular to the Z-axis direction. The sixth magnetic layer 60 has a role of generating a high frequency magnetic field during writing. The sixth magnetic layer 60 functions as, for example, a magnetization rotation layer (oscillation layer).

  The seventh magnetic layer 70 functions as, for example, a second magnetization fixed layer. The direction of the magnetization 70m of the seventh magnetic layer 70 is, for example, substantially perpendicular to the film surface. The magnetization 70m of the seventh magnetic layer 70 is in a direction having a component in the stacking direction. The direction of the magnetization 70m of the seventh magnetic layer 70 is substantially perpendicular to the film surface. The fourth nonmagnetic layer 34 functions as a second spacer layer.

  For the first magnetic layer 10, the second magnetic layer 20, and the seventh magnetic layer 70, for example, a perpendicular magnetization film is used. For the sixth magnetic layer 60, for example, an in-plane magnetization film is used. With such a structure, for example, by utilizing the leakage magnetic field from the sixth magnetic layer 60, the magnetization reversal of the second magnetic layer 20 is facilitated by the magnetic resonance effect.

  The magnetic resonance frequency of the second magnetic layer 20 can be measured using, for example, a damping measurement method. For example, a probe is applied to one end of the first stacked unit SB1 and one end of the second stacked unit SB2, and measurement is performed. In this case, a plurality of magnetic resonance frequencies may be measured. For example, the material and composition of the second magnetic layer 20 can be obtained using mass spectrometry or X-ray diffraction. The resonance frequency of the second magnetic layer 20 can be identified from the frequency that matches the resonance frequency band that can be estimated from the material. Thereby, the characteristic If1 of the first stacked unit SB1 can be measured.

The magnetic resonance frequency can also be obtained by measuring the spectrum of Ferromagnetic Resonance (FMR).
For example, the material and composition of the sixth magnetic layer 60 can be obtained by using mass spectrometry or X-ray diffraction. Thereby, for example, the oscillation characteristics of the sixth magnetic layer 60 can be obtained.

FIG. 11A and FIG. 11B are schematic views illustrating magnetization.
FIG. 11A illustrates the magnetization in the perpendicular magnetization film. FIG. 11B illustrates the magnetization in the in-plane magnetization film.
As shown in FIGS. 11A and 11B, an in-plane direction SD2 is defined as one direction that intersects (eg, is perpendicular to) the Z-axis direction. The in-plane direction SD2 is a direction in the XY plane. The in-plane magnetization component 72b of the magnetization 72 is a component obtained by projecting the magnetization 72 onto the XY plane. The in-plane magnetization component 72b is in the in-plane direction SD2, and the in-plane magnetization component 72b is parallel to the in-plane direction SD2. The perpendicular magnetization component 72a of the magnetization 72 is a component obtained by projecting the magnetization 72 in the Z-axis direction. The perpendicular magnetization component 72a is parallel to the Z-axis direction.

  As shown in FIG. 11A, in the perpendicular magnetization film, the perpendicular magnetization component 72a has a larger magnetization state than the in-plane magnetization component 72b. In the perpendicular magnetization film, it is desirable in terms of operation characteristics that the magnetization direction is substantially perpendicular to the film surface.

  As shown in FIG. 11B, in the in-plane magnetization film, the in-plane magnetization component 72b has a larger magnetization state than the perpendicular magnetization component 72a. In the in-plane magnetization film, it is desirable in terms of operating characteristics that the magnetization direction is substantially parallel to the film surface.

  For example, the perpendicular magnetization component along (for example, parallel to) the Z axis direction of the magnetization 10 m of the first magnetic layer 10 intersects with (for example, perpendicular to) the in-plane magnetization of the magnetization 10 m of the first magnetic layer 10. Greater than ingredients. The perpendicular magnetization component of the magnetization 20 m of the second magnetic layer 20 is larger than the in-plane magnetization component of the magnetization 20 m of the second magnetic layer 20. The perpendicular magnetization component of the magnetization 60 m of the sixth magnetic layer 60 is smaller than the in-plane magnetization component of the magnetization 60 m of the sixth magnetic layer 60.

  For convenience of explanation, the direction from the first stacked unit SB1 to the second stacked unit SB2 is referred to as “up” or “upward”. The direction from the second stacked unit SB2 toward the first stacked unit SB1 is referred to as “down” or “downward”.

  As already described, the direction of the magnetization 10m of the first magnetic layer 10 is substantially fixed. The direction of the magnetization 70m of the seventh magnetic layer 70 is substantially fixed.

  As shown in FIG. 10, in the stacked body SB0, the direction of the magnetization 10m of the first magnetic layer 10 is upward, and the direction of the magnetization 70m of the seventh magnetic layer 70 is downward. The direction of the component in the Z-axis direction of the magnetization 10m of the first magnetic layer 10 is, for example, opposite to the direction of the component in the Z-axis direction of the magnetization 70m of the seventh magnetic layer 70. Various modifications can be made to the direction of the magnetization 10 m of the first magnetic layer 10 and the direction of the magnetization 70 m of the seventh magnetic layer 70. For example, both the direction of the magnetization 10m of the first magnetic layer 10 and the direction of the magnetization 70m of the seventh magnetic layer 70 may be upward or downward, or one may be upward and the other may be downward.

  In the stacked body SB0, for example, an electronic current can flow through the first stacked unit SB1 and the second stacked unit SB2 via the first conductive layer 81 and the second conductive layer 82. Electron current is the flow of electrons. When the current flows upward, the electron current flows downward.

  When an electron current is passed in a direction perpendicular to the film surface, the magnetization 60m in the sixth magnetic layer 60 of the magnetic field source precesses. Thereby, a rotating magnetic field (high frequency magnetic field) is generated. The frequency of the high frequency magnetic field is, for example, about 1 GHz to 60 GHz. The high-frequency magnetic field has a component perpendicular to the magnetization 20m of the second magnetic layer 20 (component in the direction of the hard axis of the second magnetic layer 20). At least a part of the high-frequency magnetic field generated from the sixth magnetic layer 60 is applied in the direction of the hard axis of the second magnetic layer 20. When the high-frequency magnetic field generated from the sixth magnetic layer 60 is applied in the direction of the hard axis of the second magnetic layer 20, the magnetization 20m of the second magnetic layer 20 is easily reversed.

  In the stacked body SB0, the direction of the magnetization 20m of the second magnetic layer 20 can be controlled by passing an electron current through the first stacked unit SB1 and the second stacked unit SB2. Specifically, the direction of the magnetization 20m of the second magnetic layer 20 is reversed by changing the direction (polarity) in which the electron current flows. In the case of storing information, for example, “0” and “1” are respectively assigned according to the direction of the magnetization 20 m of the second magnetic layer 20. The stacked body SB0 has a first state or a second state different from the first state. Each of the first state and the second state corresponds to two different directions of the magnetization 20m of the second magnetic layer 20.

  As described above, the width (diameter) of the sixth magnetic layer 60 is preferably 35 nm or less. When the width of the sixth magnetic layer 60 is larger than 35 nm, for example, vortex (reflux magnetic domain) is generated with precession of the magnetization 60 m of the sixth magnetic layer 60. By setting the equivalent circle diameter of the cross-sectional shape of the sixth magnetic layer 60 to 35 nm or less and the thickness of the sixth magnetic layer 60 to 0.5 nm to 3.5 nm, for example, generation of vortex can be suppressed. . Thereby, for example, the high frequency magnetic field generated from the sixth magnetic layer 60 can be appropriately acted by the magnetization reversal of the second magnetic layer 20 to assist the magnetization reversal of the second magnetic layer 20. For example, a sufficient magnetic field strength at which the magnetization 20m is reversed can be obtained at the position of the second magnetic layer 20.

The equivalent circular diameter of the cross-sectional shape of the sixth magnetic layer 60 (cross-sectional shape when cut in a plane perpendicular to the Z-axis direction) is R (nm), and the half value of “R” is r (= R / 2) When (nm) and the layer thickness are t (nm), it is desirable that the size satisfy the relational expression r <0.419t ² −2.86t + 19.8.

  In the specification of the present application, the “equivalent circle diameter” means a circle having the same area as the area of the target planar shape, and means the diameter of the circle. For example, when the cross-sectional shape of the sixth magnetic layer 60 is a circle, “R” means a diameter. When the cross-sectional shape of the sixth magnetic layer 60 is an ellipse, “R” means the diameter of a circle having the same area as the area of the ellipse. When the cross-sectional shape of the sixth magnetic layer 60 is a polygon, “R” means the diameter of a circle having the same area as the polygon.

  According to the nonvolatile memory device 610 according to the embodiment, a nonvolatile memory device in which malfunctions are suppressed can be provided. For example, even when the width of the magnetic memory element 116 is set to 35 nm or less, the magnetization reversal of the second magnetic layer 20 can be assisted in bidirectional writing. Thereby, for example, malfunction during writing is suppressed. The magnitude of the current during writing (write current) can also be reduced.

  In the stacked body SB0, the magnetization of the second magnetic layer 20 and the magnetization of the sixth magnetic layer 60 are magnetostatically coupled. Thereby, for example, the magnitude of current during writing can be reduced.

  As a specific example of the operation in the stacked body SB0, an example of a “write” operation will be described first.

FIG. 12A to FIG. 12D and FIG. 13A to FIG. 13D are schematic views illustrating the operation of the nonvolatile memory device according to the first embodiment.
These drawings illustrate the state of the first stacked unit SB1 and the second stacked unit SB2 during the “write” operation in the stacked body SB0. In the write operation of the second magnetic layer 20, an electron current e <b> 1 or e <b> 2 (write current) is passed across the film surface of the first magnetic layer 10 and the film surface of the second magnetic layer 20. Here, a case where the magnetoresistive effect via the first nonmagnetic layer 31 is a normal type will be described.

  In the “normal type” magnetoresistive effect, the electrical resistance when the magnetizations of the magnetic layers on both sides of the nonmagnetic layer are parallel to each other is lower than the electrical resistance when antiparallel. In the normal type, the electrical resistance between the first magnetic layer 10 and the second magnetic layer 20 via the first nonmagnetic layer 31 is such that the magnetization 10 m of the first magnetic layer 10 is the magnetization 20 m of the second magnetic layer 20. Is lower than when antiparallel.

12A to 12D illustrate a case where the direction of the magnetization 20m of the second magnetic layer 20 is reversed from upward to downward.
FIG. 12A illustrates a state in which the electronic current e1 starts to flow. FIG. 12D illustrates a state in which the electron current e1 has been passed (a state in which the magnetization 20m is reversed). FIG.12 (b) and FIG.12 (c) have illustrated the state in the middle.

  As shown in FIG. 12A, when the direction of the magnetization 20m is reversed from upward to downward, an electron current e1 is supplied from the second stacked unit SB2 toward the first stacked unit SB1. For example, the electronic current e1 is allowed to flow downward.

  When the electron current e1 is flowed downward, among the electrons that have passed through the first nonmagnetic layer 31, electrons having spins in the same direction as the magnetization 10m of the first magnetic layer 10 (upward in this example) Passes through the magnetic layer 10. On the other hand, electrons having spins in the opposite direction (downward in this example) with respect to the magnetization 10 m of the first magnetic layer 10 are reflected at the interface between the first magnetic layer 10 and the first nonmagnetic layer 31. The angular momentum of the spin of the reflected electrons is transmitted to the second magnetic layer 20 and acts on the magnetization 20m of the second magnetic layer 20.

  As shown in FIG. 12B, when an electron current e1 is passed through the second stacked unit SB2, the magnetization 60m of the sixth magnetic layer 60 precesses and a rotating magnetic field is generated. Electrons that have passed through the seventh magnetic layer 70 having a magnetization 70m in a direction substantially perpendicular to the film surface have spins in the same direction as the magnetization 70m of the seventh magnetic layer 70. When the electrons flow to the sixth magnetic layer 60, the angular momentum of the spin is transmitted to the sixth magnetic layer 60. This acts on the magnetization 60 m of the sixth magnetic layer 60. Thereby, so-called spin transfer torque acts on the sixth magnetic layer 60. By supplying the electron current e1, the magnetization 60m precesses. The spin polarization degree of the electrons that have passed through the sixth magnetic layer 60 is lost by the passage of the sixth nonmagnetic layer 36.

  As shown in FIG. 12C, when the magnetization 60m of the sixth magnetic layer 60 precesses, the direction of the magnetization 20m is reversed from upward to downward. In this operation, spin-polarized electrons reflected at the interface between the action of the rotating magnetic field from the sixth magnetic layer 60 and the first magnetic layer 10 are used. The magnetization 10m of the first magnetic layer 10 is not reversed.

  As shown in FIG. 12D, when the supply of the electron current e1 is stopped, the precession of the magnetization 60m is stopped. Thereby, the direction of the magnetization 20m is held in a state where the direction is reversed from the upward direction to the downward direction. For example, “0” is assigned to the state of the second magnetic layer 20 having the magnetization 20 m in this direction. In the stacked body SB0, for example, a state in which the direction of the magnetization 20m of the second magnetic layer 20 is downward corresponds to the first state.

FIG. 13A to FIG. 13D illustrate a case where the direction of the magnetization 20m is reversed from downward to upward.
FIG. 13A illustrates a state in which the electronic current e2 has started to flow. FIG. 13D illustrates a state where the electron current e2 has been passed (a state where the magnetization 20m is reversed). FIG. 13B and FIG. 13C illustrate a state in the middle.

  As shown in FIG. 13A, when the direction of the magnetization 20m is reversed from the downward direction to the upward direction, the electron current e2 flows from the first stacked unit SB1 to the second stacked unit SB2. For example, the electron current e2 is passed upward.

  As shown in FIG. 13B, when the electron current e2 is passed, the magnetization 60m of the sixth magnetic layer 60 precesses and a rotating magnetic field is generated. The angular momentum of the electron spin is transmitted to the sixth magnetic layer 60 and acts on the magnetization 60 m of the sixth magnetic layer 60. Thereby, the magnetization 60m precesses.

  When the electron current e2 flows upward, electrons having spins in the same direction as the magnetization 10m of the first magnetic layer 10 (upward in this example) pass through the first magnetic layer 10 and are transmitted to the second magnetic layer 20. Is done. Thereby, the action of electrons having upward spin and the action of the rotating magnetic field from the sixth magnetic layer 60 act on the magnetization 20m.

  As shown in FIG. 13C, the direction of the magnetization 20m of the second magnetic layer 20 is reversed from downward to upward. In this operation, the action of spin-polarized electrons and the rotating magnetic field from the sixth magnetic layer 60 are used. The magnetization 10m of the first magnetic layer 10 is not reversed.

  As shown in FIG. 13 (d), when the supply of the electron current e2 is stopped, the precession of magnetization 60m is stopped. Thereby, the direction of the magnetization 20m is maintained in a state where the direction is reversed from the downward direction to the upward direction. For example, “1” is assigned to the state of the second magnetic layer 20 having the magnetization 20 m in this direction. In the stacked body SB0, for example, the state in which the direction of the magnetization 20m of the second magnetic layer 20 is upward corresponds to the second state.

  Based on such an action, “0” or “1” is appropriately assigned to each of the plurality of states of the second magnetic layer 20. Thereby, “writing” in the stacked body SB0 is performed.

  When the magnetoresistive effect is “reverse type”, the electrical resistance between the first magnetic layer 10 and the second magnetic layer 20 via the first nonmagnetic layer 31 is such that the magnetization 10m of the first magnetic layer 10 is the first. When it is parallel to the magnetization 20m of the two magnetic layers 20, it is higher than when it is antiparallel. The “write” operation in the reverse type is the same as in the normal type.

  In this example, for example, the first state is “0” and the second state is “1”. The first state may be “1” and the second state may be “0”. The first state and the second state are not limited to “0” or “1”, but may be other states. The number of states provided in the stacked body SB0 may be three or more. The stacked body SB0 may be a multi-bit storage element.

  The setting of the first state or the second state is performed by the control unit 550. For example, the first state setting corresponds to “write”, and the second state setting corresponds to “erase”. The setting of the second state may correspond to “write”, and the setting of the first state may correspond to “erase”.

  The supply of the electronic currents e1 and e2 is performed by the control unit 550, for example. The controller 550 supplies, for example, electron currents e1 and e2 of 10 nanoseconds or more to the stacked body SB0 during the write operation. Thereby, for example, the direction of the magnetization 20m is appropriately reversed by supplying the electron currents e1 and e2. For memory applications that operate at high speed, it is 1 nanosecond or more. Thereby, for example, the time required for the write operation can be suppressed while the magnetization is appropriately reversed.

Next, an example of a “read” operation will be described.
The detection of the direction of the magnetization 20m of the second magnetic layer 20 in the stacked body SB0 is performed using, for example, the magnetoresistance effect. In the magnetoresistive effect, the electrical resistance changes depending on the relative direction of magnetization of each layer. When the magnetoresistive effect is used, for example, a sense current is passed between the first magnetic layer 10 and the second magnetic layer 20, and the magnetoresistance is measured. The current value of the sense current is smaller than the current value corresponding to the electron currents e1 and e2 that flow when writing (memory).

FIG. 14A and FIG. 14B are schematic views illustrating the operation of the nonvolatile memory device according to the first embodiment.
These drawings illustrate the state of the first stacked unit SB1 during the “read” operation in the stacked body SB0. In these drawings, the second stacked unit SB2, the first conductive layer 81, the second conductive layer 82, and the sixth nonmagnetic layer 36 are omitted.

  FIG. 14A illustrates a case where the direction of the magnetization 10 m of the first magnetic layer 10 is the same as the direction of the magnetization 20 m of the second magnetic layer 20. FIG. 14B illustrates a case where the direction of the magnetization 10 m of the first magnetic layer 10 is antiparallel (reverse) to the direction of the magnetization 20 m of the second magnetic layer 20.

As shown in FIGS. 14A and 14B, a sense current e3 is supplied to the first stacked unit SB1 to detect an electrical resistance.
In the normal type magnetoresistance effect, the resistance in the state of FIG. 14A is lower than the resistance in the state of FIG. In the reverse type magnetoresistive effect, the resistance in the state of FIG. 14A is higher than the resistance in the state of FIG.

  By associating “0” and “1” with each of these resistances in a plurality of states, binary data storage can be read out. The direction of the sense current e3 may be opposite to the direction illustrated in FIGS. 14 (a) and 14 (b).

  The supply of the sense current e3 is performed by the control unit 550, for example. For example, the control unit 550 supplies a sense current e3 of less than 10 nanoseconds to the stacked body SB0 during a read operation. Thereby, for example, reversal of the direction of the magnetization 20m due to the supply of the sense current e3 is suppressed. More preferably, it is 5 nanoseconds or less. Thereby, the reversal of magnetization due to the supply of the sense current e3 is more appropriately suppressed.

  In this way, the control unit 550 sets the time for supplying current to the stacked body SB0 during “writing” longer than the time for supplying current to the stacked body SB0 during “reading”. For example, the control unit 550 supplies a current for the first time to the stacked body SB0 at “write”, and supplies a current for the second time to the stacked body SB0 at “read”. At this time, the first time is longer than the second time. Thereby, for example, a stable “write” operation and a stable “read” operation can be obtained.

  As a memory operation equivalent to a DRAM, a write current in 10 nanoseconds to 30 nanoseconds is assumed. On the other hand, a write current in 1 nanosecond to 3 nanoseconds is assumed as an application corresponding to a cache memory.

  The writing time (first time) is, for example, 10 nanoseconds or more, and the reading time (second time) is less than that. In the magnetization reversal of 3 nanoseconds or less, the magnetization becomes difficult to receive the influence of heat (assist effect by heat), so that the current for reversal starts to increase. The vicinity of 1 nanosecond is called a dynamic region, and since the magnetization is not affected by heat, the current required for reversal is further increased.

  For example, writing is performed in 10 nanoseconds or more, and reading is performed in 3 nanoseconds or less. In the case of writing within 1 nanosecond or more and 3 nanoseconds or less, the erroneous writing rate can be further reduced by reading out under 3 nanoseconds or less with a current value smaller than the writing.

  As described above, in the stacked body SB0, the second stacked unit SB2 functions as a magnetic field generation source. The first stacked unit SB1 functions as a magnetic storage unit. Hereinafter, the second stacked unit SB2 may be referred to as a magnetic field generation source or STO (Spin Torque Oscillator). On the other hand, the first stacked unit SB1 may be referred to as a magnetic storage unit or MTJ.

  As described above, writing to the second magnetic layer 20 that is a storage layer of the MTJ element is performed by, for example, a spin torque writing method. In such a stacked body SB0, for example, it is desired that the width of the stacked body SB0 be 35 nm or less because of a demand for higher storage density. The width of the stacked body SB0 is, for example, the length of the stacked body SB0 in the X-axis direction or the Y-axis direction. When the shape projected on the XY plane of the magnetic memory element 110 is a circle or an ellipse, the width of the stacked body SB0 is the diameter (major axis) of the stacked body SB0.

  In the stacked body SB0, the second nonmagnetic layer 32 overlaps the first magnetic layer 10 in a direction orthogonal to the Z-axis direction. As a result, the effective damping constant of the first magnetic layer 10 increases. Thereby, in the stacked body SB0, the fluctuation of the magnetization of the first magnetic layer 10 is suppressed during writing, and an increase in current during writing is suppressed.

  Hereinafter, the configurations of the magnetic memory element 110, the magnetic memory element 111, the magnetic memory element 112, the magnetic memory element 113, the magnetic memory element 114, the magnetic memory element 115, and the magnetic memory element 116 will be described. The following description is applicable to any magnetic memory element according to the embodiment. The composition ratio may be changed in the material of each layer.

  The first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18 are, for example, from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr). It is preferable to use a metal material containing at least one selected element. Furthermore, at least one selected from the above group and at least one metal selected from the group consisting of platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), and rhodium (Rh). Including alloys can be used.

In the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18, the composition of the magnetic material contained, the conditions for the heat treatment, and the like are adjusted. Thereby, for example, characteristics such as the amount of magnetization and magnetic anisotropy can be adjusted. For the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18, for example, a rare earth-transition metal amorphous alloy such as TbFeCo and GdFeCo can be used. For the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18, for example, a laminated structure such as Co / Pt, Co / Pd, and Co / Ni may be used. For the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18, an alloy such as Fe / Pt or Fe / Pd or a laminated structure may be used. Co / Ru, Fe / Au, Ni / Cu, etc. become a perpendicular magnetization film in combination with the underlayer. In the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18, Co / Ru, Fe / Au, Ni / Cu, or the like can be used by controlling the crystal orientation direction of the film. . The first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18 include gallium (Ga), aluminum (Al), germanium (Ge), nitrogen (N), phosphorus (P), arsenic (As), An additive such as boron (B) and silicon (Si) may be included. For example, Mn _x Ga _y , Mn _x Ge _y, or the like may be used for the first magnetic layer 10, the seventh magnetic layer 70, and the eighth magnetic layer 18. The composition ratio of x and y may be changed.

  For example, the fifth magnetic layer 50 includes a metal material containing at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr). Can be used. The fifth magnetic layer 50 is selected from the group consisting of at least one selected from the above group and platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), and rhodium (Rh). An alloy containing at least one of the metals can be used.

In the fifth magnetic layer 50, the composition of the magnetic material contained, conditions for heat treatment, and the like are adjusted. For example, characteristics such as the amount of magnetization and magnetic anisotropy can be adjusted. For example, a rare earth-transition metal amorphous alloy such as TbFeCo and GdFeCo can be used for the fifth magnetic layer 50. For example, the fifth magnetic layer 50 may have a stacked structure such as Co / Pt, Co / Pd, and Co / Ni. For the fifth magnetic layer 50, an alloy such as Fe / Pt or Fe / Pd or a laminated structure may be used. Co / Ru, Fe / Au, Ni / Cu, etc. become a perpendicular magnetization film in combination with the underlayer. In the fifth magnetic layer 50, Co / Ru, Fe / Au, Ni / Cu, or the like can be used by controlling the crystal orientation direction of the film. In the fifth magnetic layer 50, gallium (Ga), aluminum (Al), germanium (Ge), nitrogen (N), phosphorus (P), arsenic (As), boron (B), and
An additive such as silicon (Si) may be included. For example, the fifth magnetic layer 50 may be made of CoFe, CoFeB, MnGa, MnGe, or the like. Various composition ratios may be appropriately changed.

For the fifth magnetic layer 50, for example, a Heusler alloy may be used. The Heusler alloy is, for example, an alloy having an L2 ₁ structure and a composition such as X ₂ YZ. For example, a Heusler alloy containing at least one of Co, Mn, Fe, Ni, Cu, Rh, Ru, and Pd is included.

For example, the fifth magnetic layer 50 includes a first Heusler alloy. The first Heusler _{alloy, Co 2 FeSi, Co 2 FeAl} , Co 2 FeGa, Co 2 MnGe, Co 2 MnSn, Co 2 MnSi, Co 2 MnGa, Co 2 MnAl, Co 2 MnSb, Co 2 CrGa, Ni 2 MnIn, _{Ni 2 MnGa, Ni 2 MnSn,} Ni 2 MnSb, Ni 2 FeGa, Pd 2 MnSb, Pd 2 MnSn, Cu 2 MnAl, Cu 2 MnSn, Cu 2 MnIn, Rh 2 MnGe, Rh 2 MnPb, Rh 2 MnSn, Pd 2 It contains at least one of MnGe, Rh ₂ FeSn, Ru ₂ FeSn, and Rh ₂ FeSb.

  By using the first Heusler alloy for the fifth magnetic layer 50, for example, the saturation magnetization Ms of the fifth magnetic layer 50 can be increased. Thus, when the fifth magnetic layer 50 and the second magnetic layer 20 are ferromagnetically coupled, antiferromagnetically coupled, or magnetostatically coupled, the magnetic resonance frequency can be reduced and the magnetic resonance effect is likely to occur. When the fifth magnetic layer 50 and the third magnetic layer 30 are ferromagnetically coupled, antiferromagnetically coupled, or magnetostatically coupled, the magnetic resonance frequency can be reduced and the magnetic resonance effect is likely to occur.

For example, the fifth magnetic layer 50 may include a second Heusler alloy. The second Heusler alloy is Co ₂ HfSn, Co ₂ ZrSn, Co ₂ HfAl, Co ₂ ZrAl, Co ₂ HfGa, Co ₂ TiSi, Co ₂ TiGe, Co ₂ TiSn, Co ₂ TiGa, Co ₂ TiAl, Co ₂ VGa, At least of Co ₂ VAl, Co ₂ TaAl, Co ₂ NbGa, Co ₂ NbAl, Co ₂ VSn, Co ₂ NbSn, Co ₂ CrAl, Rh ₂ NiSn, Rh ₂ NiGe, Mn ₂ WSn, Fe ₂ MnSi, and Fe ₂ MnAl Including any one.

  The second Heusler alloy has a relatively small saturation magnetization Ms. For example, in the second Heusler alloy, Ms <400 emu / cc. Thereby, for example, the leakage magnetic field to the adjacent magnetic memory element can be reduced.

  In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, for example, from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr). A metal material containing at least one selected element can be used. In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, at least one selected from the above group, platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru) And an alloy containing at least one metal selected from the group consisting of rhodium (Rh) can be used.

  In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, the composition of the magnetic material contained, the heat treatment conditions, and the like are adjusted. For example, in the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, characteristics such as the amount of magnetization and magnetic anisotropy can be adjusted. For example, in the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, a rare earth-transition metal amorphous alloy such as TbFeCo and GdFeCo can be used. For example, the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40 may have a stacked structure such as Co / Pt, Co / Pd, and Co / Ni. In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, an alloy such as Fe / Pt or Fe / Pd or a laminated structure may be used. Co / Ru, Fe / Au, Ni / Cu, etc. become a perpendicular magnetization film in combination with the underlayer. In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, Co / Ru, Fe / Au, Ni / Cu, or the like can be used by controlling the crystal orientation direction of the film. In the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, gallium (Ga), aluminum (Al), germanium (Ge), nitrogen (N), phosphorus (P), arsenic (As), An additive such as boron (B) and silicon (Si) may be included. For example, in the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, CoFe, CoFeB, MnGa, MnGe, or the like may be used. Various composition ratios may be changed as appropriate.

For the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, for example, a Heusler alloy may be used. The Heusler alloy is, for example, an alloy having an L2 ₁ structure and a composition such as X ₂ YZ. For example, a Heusler alloy containing at least one of Co, Mn, Fe, Ni, Cu, Rh, Ru, and Pd is included.

For example, the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40 include a first Heusler alloy. The first Heusler _{alloy, Co 2 FeSi, Co 2 FeAl} , Co 2 FeGa, Co 2 MnGe, Co 2 MnSn, Co 2 MnSi, Co 2 MnGa, Co 2 MnAl, Co 2 MnSb, Co 2 CrGa, Ni 2 MnIn, _{Ni 2 MnGa, Ni 2 MnSn,} Ni 2 MnSb, Ni 2 FeGa, Pd 2 MnSb, Pd 2 MnSn, Cu 2 MnAl, Cu 2 MnSn, Cu 2 MnIn, Rh 2 MnGe, Rh 2 MnPb, Rh 2 MnSn, Pd 2 It contains at least one of MnGe, Rh ₂ FeSn, Ru ₂ FeSn, and Rh ₂ FeSb.

  By using the first Heusler alloy for the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40, for example, the saturation of the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40. The magnetization Ms can be increased. Thereby, for example, the magnetic resonance frequency in the second magnetic layer 20 and the first magnetic layer 10 can be reduced, and the magnetic resonance effect can be easily generated.

For example, the second magnetic layer 20, the third magnetic layer 30, and the fourth magnetic layer 40 may include a second Heusler alloy. The second Heusler alloy is Co ₂ HfSn, Co ₂ ZrSn, Co ₂ HfAl, Co ₂ ZrAl, Co ₂ HfGa, Co ₂ TiSi, Co ₂ TiGe, Co ₂ TiSn, Co ₂ TiGa, Co ₂ TiAl, Co ₂ VGa, At least of Co ₂ VAl, Co ₂ TaAl, Co ₂ NbGa, Co ₂ NbAl, Co ₂ VSn, Co ₂ NbSn, Co ₂ CrAl, Rh ₂ NiSn, Rh ₂ NiGe, Mn ₂ WSn, Fe ₂ MnSi, and Fe ₂ MnAl Including any one.

  The second Heusler alloy has a relatively small saturation magnetization Ms. For example, Ms <400 emu / cc. Thereby, for example, the leakage magnetic field to the adjacent magnetic memory element can be reduced.

  In the sixth magnetic layer 60, for example, a metal material containing at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr) Can be used. In the sixth magnetic layer 60, at least one selected from the above group and selected from the group consisting of platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru) and rhodium (Rh). An alloy containing at least one of the metals can be used. In the sixth magnetic layer 60, gallium (Ga), aluminum (Al), germanium (Ge), nitrogen (N), phosphorus (P), arsenic (As), boron (B), silicon (Si), etc. Additives may be included. For example, in the sixth magnetic layer 60, CoFe, CoFeB, CoFeSiB, NiFe, MnGa, MnGe, CoFeAl, CoFeSi, CoFeGe, CoFeSn, CoMnAl, CoMnSi, CoMnGe, CoMnSn, or the like may be used. Various composition ratios may be changed as appropriate.

  For example, the sixth magnetic layer 60 includes a Heusler alloy. For example, the sixth magnetic layer 60 is made of a Heusler alloy containing at least one of Co, Mn, Fe, Ni, Cu, Rh, Ru, and Pd. In the Heusler alloy, for example, the spin injection efficiency g (θ) is high. Thereby, for example, the gradient f / J in the equation (1) described later can be increased. That is, the oscillation frequency can be increased with respect to the current.

For example, the Heusler _{alloy, Co 2 MnGa, Co 2 MnAl} , Ni 2 MnIn, Ni 2 MnGa, Ni 2 MnSn, Pd 2 MnSb, Pd 2 MnSn, Cu 2 MnAl, Cu 2 MnSn, Cu 2 MnIn, Rh 2 MnGe And at least one of Rh ₂ MnPb is used.
In these Heusler alloys, the magnetization Ms is relatively small. For example, the magnetization Ms is 800 emu / cc or less. By using such a Heusler alloy, for example, (1) the inclination f / J in the above formula can be further increased, which will be described later.

For example, for the Heusler alloy, at least one of Co ₂ FeSi, Co ₂ FeAl, Co ₂ FeGa, Co ₂ MnGe, Co ₂ MnSn, and Co ₂ MnSi may be used.

  In these Heusler alloys, the magnetization Ms is relatively large. For example, the magnetization Ms is 800 emu / cc or more and 1000 emu / cc or less. Thereby, for example, the magnetic field generated by the oscillation of the magnetization of the sixth magnetic layer 60 can be increased. Due to the magnetization of the sixth magnetic layer 60, the magnetization of the sixth magnetic layer 60 is easily reversed. That is, the inversion current can be reduced.

The sixth magnetic layer _{60, Co 2 MnGa, Co 2 MnAl} , Co 2 MnSb, Co 2 CrGa, Ni 2 MnIn, Ni 2 MnGa, Ni 2 MnSn, Ni 2 MnSb, Ni 2 FeGa, Pd 2 MnSb, Pd 2 MnSn , Cu ₂ MnAl, Cu ₂ MnSn, Cu ₂ MnIn, Rh ₂ MnGe, Rh ₂ MnPb, Rh ₂ MnSn, Pd ₂ MnGe, Rh ₂ FeSn, Ru ₂ FeSn, and Rh ₂ FeSb.

  By using the above Heusler alloy for the sixth magnetic layer 60, for example, the saturation magnetization Ms of the third magnetic layer 30 can be increased. Accordingly, when the second magnetic layer 20 and the sixth magnetic layer 60 are ferromagnetically coupled, antiferromagnetically coupled, or magnetostatically coupled, the magnetic resonance effect is likely to occur.

  When the sixth magnetic layer 60 is any of the Heusler alloy, CoFeSiB, CoFe, and CoFeB, or an alloy of CoFe and another metal, Ms increases. Thereby, the coupling force of the ferromagnetic coupling, the antiferromagnetic coupling, or the magnetostatic coupling between the second magnetic layer 20 and the sixth magnetic layer 60 can be increased. The magnetization intensity of the sixth magnetic layer 60 is preferably 1000 to 1600 (emu / cc). In the LLG calculation, 1000 to 1400 (emu / cc) is more preferable.

  For example, by using a Heusler alloy for the sixth magnetic layer 60, for example, the spin injection efficiency g (θ) is increased.

For example, in the sixth magnetic layer 60 (oscillation layer), the relationship of the following equation (1) exists between the oscillation frequency f and the current density J.
f = γ / (2πα) (h (bar) / 2e) (g (θ) / Mst) J (1)
γ represents a gyro time constant. α represents a damping constant. h (bar) is a value obtained by dividing the Planck constant by 2π. g (θ) represents the spin injection efficiency. Ms is the magnetization of the oscillation layer (sixth magnetic layer 60). t is the thickness of the oscillation layer (length along the stacking direction). The slope of the oscillation characteristic of the sixth magnetic layer 60 is represented by f / J in the above equation (1).

  By using a Heusler alloy for the sixth magnetic layer 60, for example, the inclination f / J in the above formula can be increased. The value of the oscillation frequency (f) becomes higher with respect to the current density (J).

  In the embodiment, it is desirable to use such a Heusler alloy in the sixth magnetic layer 60. Thereby, the oscillation frequency with respect to the current can be increased in the oscillation layer. By switching the oscillation layer and the storage layer magnetostatically, the reversal current can be reduced.

  For example, when a Heusler alloy is used for the sixth magnetic layer 60, a leakage magnetic field may be generated around by the magnetization of the sixth magnetic layer 60. This leakage magnetic field may affect adjacent memory cells, for example. In the embodiment, it is desirable to use a magnetic shield 51 described later. Thereby, a leakage magnetic field can be suppressed.

  The second nonmagnetic layer 32 includes at least one selected from the group consisting of Ti, V, Nb, Mo, Ru, Pd, Ta, W, and Pt. The second nonmagnetic layer 32 may be an alloy including at least two selected from the group consisting of Ti, V, Nb, Mo, Ru, Pd, Ta, W, and Pt. The second nonmagnetic layer 32 includes a heavy metal material having a large spin pumping effect.

  By oxidizing the surface of the second nonmagnetic layer 32, the second nonmagnetic layer 32 may be insulated from the MTJ element. An insulating film (for example, a silicon oxide film, a silicon nitride film, or an aluminum oxide film) that overlaps with the second nonmagnetic layer 32 in the X-axis direction may be provided.

  In the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34, for example, an insulating material functioning as a nonmagnetic tunnel barrier layer can be used. For example, the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34 include aluminum (Al), titanium (Ti), zinc (Zn), zirconium (Zr), tantalum (Ta), Using an oxide, nitride, or fluoride containing at least one element selected from the group consisting of cobalt (Co), nickel (Ni), silicon (Si), magnesium (Mg), and iron (Fe) Can do. The nonmagnetic tunnel barrier layer includes, for example, an insulator, and is a nonmagnetic layer through which a current (tunnel current) due to a tunnel effect flows when a voltage is applied. The thickness of the nonmagnetic tunnel barrier layer is, for example, 2 nm or less. Thereby, when a voltage is applied, a tunnel current flows through the nonmagnetic tunnel barrier layer.

For example, in the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34, Al ₂ O ₃ , SiO ₂ , MgO, AlN, Ta—O, Al—Zr—O, Bi ₂ O ₃ , MgF ₂ , CaF ₂ , SrTiO ₃ , AlLaO ₃ , Al—N—O, MgAlO, MgZnO, MgGaO, MgGaO, ZnGaO, ZnAlO, SiZnO, BaO, SrO, Vo, TiO, Mg—Li—O, Mg— V—O, Si—N—O, or the like can be used.

  The first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34 include, for example, a nonmagnetic semiconductor (ZnOx, InMn, GaN, GaAs, TiOx, Zn, Te, or a transition metal in them. And the like can be used. Various composition ratios may be appropriately changed.

  The thicknesses of the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34 are preferably in the range of about 0.2 nanometers (nm) to 2.0 nm. Thereby, for example, the resistance is prevented from becoming excessively high while ensuring the uniformity of the insulating film.

  In the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34, for example, any one of a nonmagnetic tunnel barrier layer and a nonmagnetic metal layer can be used.

  When the nonmagnetic tunnel barrier layer is used, the thickness is preferably about 0.2 nm to about 2.0 nm.

  Examples of the nonmagnetic metal layer include copper (Cu), silver (Ag), gold (Au), chromium (Cr), zinc (Zn), gallium (Ga), niobium (Nb), molybdenum (Mo), and ruthenium. (Ru), palladium (Pd), hafnium (Hf), tantalum (Ta), tungsten (W), platinum (Pt) and any nonmagnetic metal selected from the group consisting of bismuth (Bi), or the above An alloy containing at least any two or more elements selected from the group can be used. When a nonmagnetic metal layer is used as the first nonmagnetic layer 31, the third nonmagnetic layer 33, and the fourth nonmagnetic layer 34, the thickness is preferably 1.5 nm or more and 20 nm or less. Thereby, it is possible to suppress the loss of the spin-polarized state of conduction electrons when passing through the nonmagnetic metal layer without causing interlayer coupling between the magnetic layers.

  For the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36, for example, a nonmagnetic metal layer is used. Nonmagnetic metal layers used for the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 include, for example, copper (Cu), silver (Ag), gold (Au), chromium (Cr), zinc (Zn), Gallium (Ga), niobium (Nb), molybdenum (Mo), ruthenium (Ru), palladium (Pd), hafnium (Hf), tantalum (Ta), titanium (Ti), tungsten (W), platinum (Pt), Including at least one nonmagnetic metal selected from the group consisting of bismuth (Bi), iridium (Ir), and osmium (Os), or an alloy including two or more nonmagnetic metals selected from the above group be able to.

  The nonmagnetic metal layer used for the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 includes, for example, a conductive nitride, a conductive oxide, and a conductive material containing at least one element selected from the above group. It may be at least one of the functional fluorides. For example, for the sixth nonmagnetic layer 36, for example, TiN and TaN can be used. The sixth nonmagnetic layer 36 may be a laminated film in which films of these materials are laminated. For the sixth nonmagnetic layer 36, for example, a laminated film of Ti film / Ru film / Ti film or the like can be used.

  For the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36, a material having a long spin diffusion length such as copper (Cu) can be used. As the sixth nonmagnetic layer 36, a film having a short spin diffusion length (a material having a spin disappearance function) such as ruthenium (Ru) or a layer having a structure having a short spin diffusion length is used. desirable.

  Thereby, the fall of controllability of the magnetization rotation of the sixth magnetic layer 60 can be suppressed. The magnitude of the spin transfer torque for precessing the magnetization of the sixth magnetic layer 60 is determined by the spin polarization in the first magnetic layer 10. In this configuration, the magnetization of the sixth magnetic layer 60 can be independently controlled without being affected by the spin of other electrons (spin transfer torque).

  Examples of materials for obtaining such a spin disappearance effect for the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 include ruthenium (Ru), tantalum (Ta), tungsten (W), platinum (Pt), A metal selected from the group consisting of palladium (Pd), molybdenum (Mo), niobium (Nb), zirconium (Zr), titanium (Ti) and vanadium (V), or two or more selected from these groups It is an alloy containing.

  The thicknesses of the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 are preferably set to 1.4 nm or more.

  When the thicknesses of the fifth non-magnetic layer 35 and the sixth non-magnetic layer 36 are 1.4 nm or more, in the fifth non-magnetic layer 35 and the sixth non-magnetic layer 36, conduction electrons of the fifth non-magnetic layer 35 The spin polarization can be eliminated when passing through the inside and the interface and the inside and the interface of the sixth nonmagnetic layer 36. The fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 can prevent the precession of the sixth magnetic layer 60 from changing depending on the magnetization direction of the first magnetic layer 10.

  On the other hand, if the thickness of the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 exceeds 20 nm, it is difficult to form a multilayer film pillar. Further, the strength of the rotating magnetic field generated from the sixth magnetic layer 60 is attenuated at the position of the first magnetic layer 10. Therefore, the thicknesses of the fifth nonmagnetic layer 35 and the sixth nonmagnetic layer 36 are preferably set to 20 nm or less.

  For the first conductive layer 81 and the second conductive layer 82, for example, a conductive magnetic material or a conductive nonmagnetic material is used. Examples of the conductive magnetic material include substantially the same materials as those used for the sixth magnetic layer 60 and the seventh magnetic layer 70.

  Examples of the conductive nonmagnetic material used for the first conductive layer 81 and the second conductive layer 82 include gold (Au), copper (Cu), chromium (Cr), zinc (Zn), gallium (Ga), Niobium (Nb), molybdenum (Mo), ruthenium (Ru), palladium (Pd), silver (Ag), hafnium (Hf), tantalum (Ta), titanium (Ti), tungsten (W), platinum (Pt), Any metal selected from the group consisting of bismuth (Bi) and aluminum (Al), or an alloy containing two or more metals selected from the above group can be used.

  Furthermore, the conductive nonmagnetic material used for the first conductive layer 81 and the second conductive layer 82 includes a conductive nitride, a conductive oxide, and a conductive material containing at least one element selected from the above group. It may be at least one of the functional fluorides. The conductive nonmagnetic material used for the first conductive layer 81 and the second conductive layer 82 may be carbon nanotubes, carbon nanowires, graphene, or the like.

  A conductive protective film may be provided on the first conductive layer 81 and the second conductive layer 82. In this case, for example, tantalum (Ta), ruthenium (Ru), copper (Cu), gold (Au), silver (Ag), aluminum (Al), copper (Cu), gold (Au), An alloy containing at least one element selected from the group consisting of silver (Ag) and aluminum (Al), or a material such as graphene can be used. In consideration of electromagration resistance and low resistance, the protective film may be any element selected from the group consisting of copper (Cu) and aluminum (Al), or an alloy containing these elements. desirable.

  A transistor may be directly or indirectly connected to at least one of the first conductive layer 81 and the second conductive layer 82. At this time, for example, the source portion or the drain portion of the transistor may be used as at least one of the first conductive layer 81 and the second conductive layer 82. At this time, for example, a contact portion connected to the source portion or the drain portion of the transistor may be used as at least one of the first conductive layer 81 and the second conductive layer 82.

  The shape of the first stacked unit SB1 and the shape of the second stacked unit SB2 when projected onto the XY plane are arbitrary. The shape of the first stacked unit SB1 and the shape of the second stacked unit SB2 when projected onto the XY plane are, for example, a circle, an ellipse, a flat circle, and a polygon. In the case of a polygon, it preferably has three or more corners such as a quadrangle and a hexagon. The polygon may be rounded.

  The shapes of the first stacked unit SB1 and the second stacked unit SB2 when projected onto a plane parallel to the Z-axis direction (for example, a ZX plane or a ZY plane) are arbitrary. The shape of the first stacked unit SB1 and the shape of the second stacked unit SB2 (a shape cut by a plane perpendicular to the film surface) when projected onto a plane parallel to the Z-axis direction are, for example, a tapered shape or It can have a reverse taper shape.

  Next, an example of a method for manufacturing the magnetic memory element according to the first embodiment will be described. In addition to the magnetic memory element, the following manufacturing method can be applied to other magnetic memory elements described later according to the embodiment by appropriately changing the order of forming the layers. In the following description, “material A / material B” indicates that material B is laminated on material A.

FIG. 15A to FIG. 15F are schematic cross-sectional views illustrating the method for manufacturing the magnetic memory element according to the first embodiment.
FIG. 16A to FIG. 16D are schematic cross-sectional views illustrating the method for manufacturing the magnetic memory element according to the first embodiment.

  As illustrated in FIG. 15A, a stacked body in which the fifth nonmagnetic layer 35 overlaps the eighth magnetic layer 18 in the Z-axis direction is prepared. For example, the fifth nonmagnetic layer 35 is formed on the eighth magnetic layer 18. The fifth nonmagnetic layer 35 overlaps the eighth magnetic layer 18 in the Z-axis direction. The fifth nonmagnetic layer 35 is formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

As shown in FIG. 15B, the second nonmagnetic film 32 </ b> F is formed on the eighth magnetic layer 18.
The second nonmagnetic film 32F overlaps the eighth magnetic layer 18 and the fifth nonmagnetic layer 35 in the Z-axis direction. The second nonmagnetic film 32F overlaps the eighth magnetic layer 18 and the fifth nonmagnetic layer 35 in the X-axis direction. The upper surface 32t of the second nonmagnetic film 32F is polished by, for example, CMP (Chemical Mechanical Polishing). In the CMP treatment, a silica-based slurry is used.

  As shown in FIG. 15C, a mask 86A is formed on the second nonmagnetic film 32F. The mask 86A overlaps with a part of the second nonmagnetic film 32F in the Z-axis direction. The mask 86A includes a resist. The mask 86A is patterned by an ArF immersion scanner method or an EB drawing method. The mask 86A has an opening 86h. In the opening 86h, the second nonmagnetic film 32F is exposed.

  As shown in FIG. 15D, the second nonmagnetic film 32F exposed from the mask 86A is etched. In the etching, an ion milling method or an RIE method is used. Thereby, the second nonmagnetic film 32F exposed from the mask 86A is removed. Thereby, the second nonmagnetic layer 32 is formed. A recess 32 h is formed in the second nonmagnetic layer 32. The fifth nonmagnetic layer 35 is exposed in the recess 32h.

  As shown in FIG. 15E, the first magnetic film 10F (for example, a ferromagnetic film) is formed in the recess 32h and on the mask 86A. The first magnetic film 10F is formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

  As shown in FIG. 15F, the mask 86A is removed by an organic solvent or an oxygen ashing method. Thereby, the first magnetic film 10F on the mask 86A is removed. Thereby, the first magnetic layer 10 is formed in the recess 10h. The first magnetic layer 10 overlaps the second nonmagnetic layer 32 in the X-axis direction.

  As shown in FIG. 16A, a first nonmagnetic film 31F is formed on the first magnetic layer 10 and the second nonmagnetic layer 32. The first nonmagnetic film 31F overlaps the first magnetic layer 10 and the second nonmagnetic layer 32 in the Z-axis direction. The thickness (length in the Z-axis direction) of the first nonmagnetic film 31F is, for example, 0.1 nm. A second magnetic film 20F (for example, a ferromagnetic film) is formed on the first nonmagnetic film 31F. The second magnetic film 20F overlaps the first nonmagnetic film 31F in the Z-axis direction. The first nonmagnetic film 31F and the second magnetic film 20F are formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

  As shown in FIG. 16B, a mask 86B is formed on the second magnetic film 20F. The mask 86B overlaps part of the second magnetic film 20F in the Z-axis direction. The mask 86B includes a resist. The mask 86B is patterned by an ArF immersion scanner method or an EB drawing method. The mask 86B is located on the first magnetic layer 10. In the X-axis direction, the length of the mask 86B is, for example, not less than 20 nm and not more than 30 nm.

  The second magnetic film 20F exposed from the mask 86B is etched. The first nonmagnetic film 31F exposed from the mask 86B is etched. In the etching, an ion milling method or an RIE method is used.

  Thereby, as shown in FIG. 16C, the second magnetic layer 20 and the first nonmagnetic layer 31 are formed. The second magnetic layer 20 and the first nonmagnetic layer 31 overlap the first magnetic layer 10 in the Z-axis direction.

  After the etching, an interlayer insulating film 200F is formed on the mask 86B and the second nonmagnetic layer 32. The interlayer insulating film 200F is formed by a sputtering method or ALD (Atomic Layer Deposition) in a reduced pressure atmosphere. The interlayer insulating film 200F includes at least one of silicon oxide and silicon nitride. The interlayer insulating film 200F overlaps the mask 86B in the Z-axis direction. The interlayer insulating film 200F overlaps the first nonmagnetic layer 31, the second magnetic layer 20, and the mask 86B in the X-axis direction.

  As shown in FIG. 16D, the interlayer insulating film 200F is polished by the CMP method. In polishing the interlayer insulating film 200F, a silica-based slurry is used. In polishing the interlayer insulating film 200F, the second magnetic layer 20 functions as a stopper layer. Thereby, the interlayer insulating film 200 is formed. The interlayer insulating film 200 overlaps the second magnetic layer 20 and the first nonmagnetic layer 31 in the X-axis direction. The interlayer insulating film 200 overlaps the second nonmagnetic layer 32 in the Z-axis direction.

FIG. 17A to FIG. 17E are schematic cross-sectional views illustrating another method for manufacturing the magnetic memory element according to the first embodiment.
FIG. 18A to FIG. 18D are schematic cross-sectional views illustrating another method for manufacturing the magnetic memory element according to the first embodiment.

  As illustrated in FIG. 17A, a stacked body in which the fifth nonmagnetic layer 35 overlaps the eighth magnetic layer 18 in the Z-axis direction is prepared. For example, the fifth nonmagnetic layer 35 is formed on the eighth magnetic layer 18. The fifth nonmagnetic layer 35 overlaps the eighth magnetic layer 18 in the Z-axis direction. The fifth nonmagnetic layer 35 is formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

  A second nonmagnetic film 32F2 is formed to overlap the fifth nonmagnetic layer 35 and the eighth magnetic layer 18 in the X-axis direction. The second nonmagnetic film 32F2 is formed by a sputtering method or an MBE method in a reduced pressure atmosphere. The material of the fifth nonmagnetic layer 35 may be the same as the material of the second nonmagnetic film 32F2. The fifth nonmagnetic layer 35 may be formed in the same manufacturing process as the second nonmagnetic film 32F2.

  A first magnetic film 10F is formed on the fifth nonmagnetic layer 35 and the second nonmagnetic film 32F2. The first magnetic film 10F is formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

  As shown in FIG. 17B, a mask 87A is formed on the first magnetic film 10F. The mask 87A overlaps part of the first magnetic film 10F in the Z-axis direction. The mask 87A includes a resist. The mask 87A is patterned by an ArF immersion scanner method or an EB drawing method. The mask 87A is located on the eighth magnetic layer 18. In the X-axis direction, the length of the mask 87A is, for example, not less than 20 nm and not more than 30 nm.

  As shown in FIG. 17C, the first magnetic film 10F exposed from the mask 87A is etched. Etched. In the etching, an ion milling method or an RIE method is used. As a result, the first magnetic layer 10 is formed on the fifth nonmagnetic layer 35.

  In this example, the second nonmagnetic film 32F2 exposed from the mask 87A is etched by ion milling or RIE. Thereby, a part of the second nonmagnetic film 32F2 is redeposited on the side surface 87w of the mask 87A and the side surface 10w of the first magnetic layer 10. Thereby, for example, the second nonmagnetic film 32F3 that overlaps the first magnetic layer 10 in the X-axis direction is formed. In this example, a layer including the second nonmagnetic film 32F2 and the second nonmagnetic film 32F3 is referred to as a second nonmagnetic layer 32.

  As shown in FIG. 17D, an interlayer insulating film 200F1 is formed on the mask 87A and the second nonmagnetic layer 32. The interlayer insulating film 200F1 is formed by a sputtering method or an ALD method in a reduced pressure atmosphere. The interlayer insulating film 200F1 overlaps the mask 87A in the Z-axis direction. The interlayer insulating film 200F1 includes at least one of silicon oxide and silicon nitride. The interlayer insulating film 200F1 overlaps with the second nonmagnetic film 32F3, the first magnetic layer 10, and the mask 87A in the X-axis direction.

  As shown in FIG. 17E, the interlayer insulating film 200F1 is polished by the CMP method. A silica-based slurry is used for polishing the interlayer insulating film 200F1. In polishing the interlayer insulating film 200F1, the first magnetic layer 10 functions as a stopper layer. The mask 87A may be removed by an organic solvent or an oxygen ashing method.

  As shown in FIG. 18A, a first nonmagnetic film 31F is formed on the first magnetic layer 10, the second nonmagnetic layer 32, and the interlayer insulating film 200F1. The first nonmagnetic film 31F overlaps the first magnetic layer 10 and the second nonmagnetic layer 32 in the Z-axis direction. The thickness (length in the Z-axis direction) of the first nonmagnetic film 31F is, for example, 0.1 nm. A second magnetic film 20F is formed on the first nonmagnetic film 31F. The second magnetic film 20F overlaps the first nonmagnetic film 31F in the Z-axis direction. The first nonmagnetic film 31F and the second magnetic film 20F are formed by a sputtering method or an MBE method in a reduced pressure atmosphere.

  As shown in FIG. 18B, a mask 87B is formed on the second magnetic film 20F. The mask 87B overlaps with a part of the second magnetic film 20F in the Z-axis direction. The mask 87B includes a resist. The mask 87B is patterned by an ArF immersion scanner method or an EB drawing method. The mask 87B is located on the first magnetic layer 10. In the X-axis direction, the length of the mask 87B is, for example, not less than 20 nm and not more than 30 nm.

  As shown in FIG. 18C, the second magnetic film 20F exposed from the mask 87B is etched. The first nonmagnetic film 31F exposed from the mask 87B is etched. In the etching, an ion milling method or an RIE method is used.

  Thereby, the second magnetic layer 20 and the first nonmagnetic layer 31 are formed. The second magnetic layer 20 and the first nonmagnetic layer 31 overlap the first magnetic layer 10 in the Z-axis direction.

  As shown in FIG. 18D, the mask 87B is removed by an organic solvent or an oxygen ashing method. In the X-axis direction, an interlayer insulating film 200F2 that overlaps the second magnetic layer 20 and the first nonmagnetic layer 31 in the X-axis direction is formed. The interlayer insulating film 200F2 overlaps with the second nonmagnetic layer 32 in the Z-axis direction. The interlayer insulating film 200F2 includes at least one of silicon oxide and silicon nitride. The interlayer insulating film 200F2 is formed by a sputtering method or an ALD method in a reduced pressure atmosphere.

FIG. 19 is a schematic cross-sectional view illustrating another nonvolatile memory device according to the first embodiment.
As shown in FIG. 19, the nonvolatile memory device 611 includes a magnetic memory element 117. In addition, the nonvolatile storage device 611 may include a control unit 550, and the control unit 550 is omitted in FIG. In the magnetic memory element 117, the direction of the magnetization 10m of the first magnetic layer 10 is downward, and the direction of the magnetization 70m of the seventh magnetic layer 70 is upward. Thus, the direction of the magnetization 10m and the direction of the magnetization 70m may be opposite to the direction of the magnetization 10m and the direction of the magnetization 70m of the first magnetic layer 10, respectively.

  If spin information is maintained in the sixth nonmagnetic layer 36, the sixth magnetic layer 60 is affected by the spin transfer torque from the second magnetic layer 20. Thereby, the controllability of the magnetization rotation of the sixth magnetic layer 60 may be deteriorated.

  At this time, as the sixth nonmagnetic layer 36, it is desirable to use a film having a short spin diffusion length such as ruthenium (Ru) (a material having a spin disappearance function). As the sixth nonmagnetic layer 36, it is desirable to use a layer having a short spin diffusion length structure such as ruthenium (Ru). Thereby, the fall of controllability of the magnetization rotation of the sixth magnetic layer 60 can be suppressed.

  The magnitude of the spin transfer torque for precessing the magnetization 60 m of the sixth magnetic layer 60 is determined by the spin polarization in the seventh magnetic layer 70. In this configuration, the magnetization 60m of the sixth magnetic layer 60 can be independently controlled without being affected by the spin of other electrons (spin transfer torque).

  As the material for the sixth nonmagnetic layer 36 that can obtain such a spin disappearance effect, ruthenium (Ru), tantalum (Ta), tungsten (W), platinum (Pt), palladium (Pd), molybdenum ( A metal selected from the group consisting of Mo), niobium (Nb), zirconium (Zr), titanium (Ti) and vanadium (V), or an alloy containing two or more selected from these groups. it can.

  The thickness of the sixth nonmagnetic layer 36 is desirably set to 1.4 nm or more.

  When the thickness of the sixth nonmagnetic layer 36 is 1.4 nm or more, in the sixth nonmagnetic layer 36, the spin polarization disappears when conduction electrons pass through the inside and the interface of the sixth nonmagnetic layer 36. . The sixth nonmagnetic layer 36 can prevent the precession of the sixth magnetic layer 60 from changing depending on the direction of the magnetization 20 m of the second magnetic layer 20.

  On the other hand, if the thickness of the sixth nonmagnetic layer 36 exceeds 20 nm, it becomes difficult to form a pillar in the multilayer film. Furthermore, the strength of the rotating magnetic field generated from the sixth magnetic layer 60 is attenuated at the position of the second magnetic layer 20. Therefore, the thickness of the sixth nonmagnetic layer 36 is desirably set to 20 nm or less.

  As the sixth nonmagnetic layer 36, a laminated film can be used in addition to the single layer film described above. This laminated film includes, for example, ruthenium (Ru), tantalum (Ta), tungsten (W), platinum (Pt), palladium (Pd), molybdenum (Mo), niobium (Nb), zirconium (Zr), titanium (Ti ) And vanadium (V), or a layer containing an alloy containing two or more selected from the group, and a copper (Cu) layer laminated on at least one side of the layer, It can have the laminated structure of.

  Furthermore, the laminated film used for the sixth nonmagnetic layer 36 is, for example, ruthenium (Ru), tantalum (Ta), tungsten (W), platinum (Pt), palladium (Pd), molybdenum (Mo), niobium (Nb). ), A metal selected from the group consisting of zirconium (Zr), titanium (Ti) and vanadium (V), or an alloy containing two or more selected from the group, and a first layer comprising: Laminated on at least one side, aluminum (Al), magnesium (Mg), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), vanadium (V), chromium (Cr), tantalum (Ta) And a second layer containing an oxide containing at least one element selected from the group consisting of tungsten (W) and ruthenium (Ru). It can be.

FIG. 20A to FIG. 20J are schematic cross-sectional views illustrating other magnetic memory elements according to the first embodiment.
As shown in FIGS. 20A to 20F, in the magnetic memory element 121 to the magnetic memory element 126, the second magnetic layer 20, the first nonmagnetic layer 31, the first magnetic layer 10, and the sixth nonmagnetic element. The layer 36, the seventh magnetic layer 70, the fourth nonmagnetic layer 34, and the sixth magnetic layer 60 are laminated in this order. The second nonmagnetic layer 32 overlaps at least part of the first magnetic layer 10 in the X-axis direction. Thus, the stacking order of the stacked body SB0 may be the order shown in FIGS. 20 (a) to 20 (f).

  In the magnetic memory element 121 and the magnetic memory element 122, the direction of the Z-axis direction component of the magnetization 10m of the first magnetic layer 10 is opposite to the direction of the Z-axis direction component of the magnetization 70m of the seventh magnetic layer 70. is there. Thereby, for example, at the position of the second magnetic layer 20, it is possible to suppress the influence of the leakage magnetic field caused by the magnetization 10 m of the first magnetic layer 10 and the magnetization 70 m of the seventh magnetic layer 70.

  In the magnetic memory element 121 and the magnetic memory element 122, the first magnetic layer 10 and the seventh magnetic layer 70 may be antiferromagnetically coupled via the sixth nonmagnetic layer 36. Such a structure in which the directions of mutual magnetization are antiferromagnetically coupled and antiparallel via the nonmagnetic layer is called a synthetic anti-ferromagnetic (SAF) structure. In this example, a stack of “first magnetic layer (for example, first magnetic layer 10) / nonmagnetic layer (for example, sixth nonmagnetic layer 36) / second magnetic layer (for example, seventh magnetic layer 70)”. The structure corresponds to the SAF structure.

  By using the SAF structure, the magnetization fixing force of each other is enhanced, and resistance to an external magnetic field and thermal stability are improved. In this structure, the leakage magnetic field applied in the direction perpendicular to the film surface at the position of the magnetic storage layer (for example, the second magnetic layer 20) can be made substantially zero.

  For the nonmagnetic layer (intermediate layer) in the SAF structure, a metal material such as ruthenium (Ru), iridium (Ir), or osmium (Os) is used. The thickness of the nonmagnetic layer is set to 3 nm or less, for example. Thereby, a sufficiently strong antiferromagnetic coupling can be obtained through the nonmagnetic layer.

  The sixth nonmagnetic layer 36 is, for example, any metal selected from the group consisting of ruthenium (Ru), osmium (Os), and iridium (Ir), or at least two or more selected from the group Including alloys containing any of these metals. The thickness of the sixth nonmagnetic layer 36 is, for example, 3 nm or less.

  In the magnetic memory element 123 and the magnetic memory element 124, the direction of the Z-axis direction component of the magnetization 10m of the first magnetic layer 10 is the same as the direction of the Z-axis direction component of the magnetization 70m of the seventh magnetic layer 70. is there. Thus, the direction of the magnetization 10m may be parallel to the direction of the magnetization 70m.

  In the magnetic memory element 125 and the magnetic memory element 126, the direction of the magnetization 10m and the direction of the magnetization 70m are inclined with respect to the Z-axis direction. The direction of the magnetization 10m and the direction of the magnetization 70m may not be parallel to the Z-axis direction. The direction of the magnetization 10 m and the direction of the magnetization 70 m have at least a component in the Z-axis direction.

  As shown in FIG. 20G and FIG. 20H, in the magnetic memory element 127 and the magnetic memory element 128, the first magnetic layer 10, the first nonmagnetic layer 31, the second magnetic layer 20, the sixth non-magnetic layer. The magnetic layer 36, the seventh magnetic layer 70, the fourth nonmagnetic layer 34, and the sixth magnetic layer 60 are laminated in this order. Thus, the stacking order of the stacked body SB0 may be the order shown in FIGS. 20 (g) and 20 (h).

  As shown in FIGS. 20I and 20J, in the magnetic memory element 129 and the magnetic memory element 130, the second magnetic layer 20, the first nonmagnetic layer 31, the first magnetic layer 10, and the sixth nonmagnetic element. The layer 36, the sixth magnetic layer 60, the fourth nonmagnetic layer 34, and the seventh magnetic layer 70 are laminated in this order. Thus, the stacking order of the stacked body SB0 may be the order shown in FIG. 20 (i) and FIG. 20 (j).

In the magnetic memory element 123,124,127,128,129 or 130, a write current _{I W} to the laminate SB0 through the first conductive layer 81 and the second conductive layer 82. The direction of the write current I _W is optional. By applying a magnetic field opposite to the direction of the magnetization 70m of the seventh magnetic layer 70, the direction of the rotating magnetic field generated in the sixth magnetic layer 60 and the direction in which the second magnetic layer 20 magnetization 20m precesses. Can be matched to each other.

  In the stacking order of the magnetic memory element 110 and the magnetic memory element 116, for example, the second magnetic layer 20 is compared with a configuration in which the seventh magnetic layer 70 is disposed between the second magnetic layer 20 and the sixth magnetic layer 60, for example. And the sixth magnetic layer 60 are close to each other. Thereby, the rotating magnetic field generated in the sixth magnetic layer 60 can be applied to the second magnetic layer 20 more appropriately. The magnetization reversal in the second magnetic layer 20 can be assisted more efficiently.

FIG. 21 is a schematic view illustrating another nonvolatile memory device according to the first embodiment.
As shown in FIG. 21, the nonvolatile memory device 612 includes a magnetic memory element 118 and a control unit 550. In the magnetic memory element 118, the second magnetic layer 20 includes a first portion 21 and a second portion 22. Other than this, the configuration described for the magnetic memory element 110 can be applied to the magnetic memory element 118.

  The direction of the magnetization 21m of the first portion 21 is variable. The second portion 22 overlaps the first portion 21 in the Z-axis direction. The second portion 22 is stacked with the first portion 21 in the Z-axis direction. In this example, the second portion 22 is provided between the first magnetic layer 10 and the first portion 21. The first portion 21 may be provided between the first magnetic layer 10 and the second portion 22. The direction of the magnetization 22m of the second portion 22 is variable. The magnetization 21m of the first portion 21 is ferromagnetically coupled, antiferromagnetically coupled, or magnetostatically coupled to the magnetization 22m of the second portion 22. The magnetic resonance frequency of the second portion 22 is lower than the magnetic resonance frequency of the first portion 21. The magnetic resonance frequency of the first portion 21 is, for example, 20 GHz or more. The magnetic resonance frequency of the second portion 22 is, for example, less than 20 GHz.

  For example, an alloy is used for the first portion 21 and the second portion 22. The concentration of at least one element contained in the second portion 22 is different from the concentration of the same element contained in the first portion 21. The composition ratio of the alloy included in the second portion 22 is different from the composition ratio of the alloy included in the first portion 21. The second portion 22 is, for example, a portion in the second magnetic layer 20 where the composition ratio of the first portion 21 and the alloy is changed.

  The material of the second portion 22 may be different from the material of the first portion 21. In this case, each of the first portion 21 and the second portion 22 can be regarded as one layer included in the second magnetic layer 20. The second magnetic layer 20 may be a stacked body including a first layer and a second layer.

  In the nonvolatile memory device 612, the magnetization 21m of the first portion 21 and the magnetization 22m of the second portion 22 are ferromagnetically coupled, antiferromagnetically coupled, or magnetostatically coupled. Thereby, for example, the Δ value of the second magnetic layer 20 in the magnetostatic state can be increased. For example, heat disturbance tolerance can be increased. Malfunctions of the magnetic memory element 110 and the nonvolatile memory device 610 can be suppressed. For example, the storage retention time of the magnetic storage element 110 can be extended.

The Δ value is, for example, the ratio between the magnetic anisotropy energy and the thermal energy of the second magnetic layer 20. The Δ value can be expressed by the following equation, for example.
Δ = Ku · V / K _B · T
In the above formula, “Ku” is an effective magnetic anisotropy constant. “V” is the volume of the second magnetic layer 20. K _B is Boltzmann's constant. “T” is the absolute temperature of the magnetic memory element 110.

  In the non-volatile memory device 612, spin-polarized electrons act on the second magnetic layer 20 by flowing current through the first stacked unit SB1 and the second stacked unit SB2 in the Z-axis direction. In the nonvolatile memory device 612, a rotating magnetic field generated by precessing the magnetization of the sixth magnetic layer 60 is applied to the second magnetic layer 20. Thereby, the direction of the magnetization 21m of the first portion 21 and the direction of the magnetization 22m of the second portion 22 of the second magnetic layer 20 are determined in accordance with the direction of the current.

  In the first portion 21 of the second magnetic layer 20, for example, the direction of the magnetization 21m of the first portion 21 is substantially perpendicular to the film surface and substantially parallel to the Z-axis direction. The magnetization 21m of the first portion 21 can be reversed. The first portion 21 has a role of storing data. The first portion 21 functions as, for example, a magnetic storage layer.

  In the second portion 22 of the second magnetic layer 20, for example, the direction of the magnetization 22m of the second portion 22 is substantially perpendicular to the film surface and substantially parallel to the Z-axis direction. The magnetization 22m of the second portion 22 can be reversed. The magnetization 22m of the second portion 22 is, for example, a magnetization reversal earlier than the magnetization 21m of the first portion 21 when a current flows in the stacked body SB0 in the Z-axis direction, and the magnetization of the magnetization 21m of the first portion 21 Assists inversion. For example, the second portion 22 functions as a trigger for the magnetization reversal of the first portion 21. The second portion 22 is called a trigger layer, for example.

  The second portion 22 also contributes to data storage retention. The second magnetic layer 20 may be a magnetic storage layer, the first portion 21 may be considered as a memory holding main body portion, and the second portion 22 as a magnetization reversal trigger portion.

  For example, the width (diameter) of the nonvolatile memory device 612 is set to 30 nm or less. Thereby, the integration degree can be increased in the MRAM. At this time, if the above-described Δ value (thermal stability constant) is small, the nonvolatile memory device 612 may not be able to keep the written data. In order to increase the Δ value, for example, the effective magnetic anisotropy constant Ku is increased. When the effective magnetic anisotropy constant Ku increases, for example, the effective magnetic anisotropy magnetic field Hk also increases. This may increase the write current and increase the resonance frequency.

  In the nonvolatile memory device 612, the magnetic resonance frequency of the second magnetic layer 20 is reduced by the second portion 22. For this reason, the magnetization 21m of the 1st part 21 and the magnetization 22m of the 2nd part 22 are reversed by applying the magnetic field of the frequency according to the magnetic resonance frequency of the reduced 2nd magnetic layer 20. FIG. In this case, inversion can be performed with a smaller current than when the first portion 21 is used alone or when a magnetic field corresponding to the magnetic resonance frequency is not applied. The magnetic resonance frequency of the second portion 22 is, for example, less than 20 GHz, and more preferably 15 GHz or less. The frequency of the rotating magnetic field generated by the sixth magnetic layer 60 can be, for example, less than 20 GHz. Thereby, for example, matching between the frequency of the rotating magnetic field generated by the sixth magnetic layer 60 and the magnetic resonance frequency of the magnetization 21m and the magnetization 22m is facilitated. For example, in the magnetic memory element 110, the degree of freedom in designing the first stacked unit SB1 and the second stacked unit SB2 can be increased.

For example, a Heusler alloy may be used for the second portion 22. For example, a Heusler alloy containing at least one of Co, Mn, Fe, Ni, Cu, Rh, Ru, and Pd may be used for the second portion 22. For example, the Heusler _{alloy, Co 2 MnGa, Co 2 MnAl} , Ni 2 MnIn, Ni 2 MnGa, Ni 2 MnSn, Pd 2 MnSb, Pd 2 MnSn, Cu 2 MnAl, Cu 2 MnSn, Cu 2 MnIn, Rh 2 MnGe And Rh ₂ MnPb can be used.

  For example, the spin injection efficiency g (θ) of the Heusler alloy is high, and a low resonance frequency can be obtained. Thereby, for example, the magnetization reversal current in the second magnetic layer 20 can be reduced.

  In these Heusler alloys, for example, the magnetization Ms is relatively small. For example, the magnetization Ms is 800 emu / cc or less. Thereby, the leakage magnetic field produced by the magnetization of the 2nd part 22 using a Heusler alloy can be suppressed.

FIG. 22 is a schematic cross-sectional view illustrating another magnetic memory element according to the first embodiment.
As shown in FIG. 22, the nonvolatile memory device 613 includes a magnetic memory element 118a. The nonvolatile storage device 613 may further include a control unit 550 (omitted in FIG. 22). In the magnetic memory element 118a, the width of the first stacked unit SB1 (cross-sectional shape when cut along a plane perpendicular to the Z-axis direction) and the width of the second stacked unit SB2 are different from each other. Other than this, the magnetic memory element 118a can have the same configuration as the magnetic memory element 110 and the magnetic memory element 116.

  For example, the cross-sectional area (first area S1) of the first stacked unit SB1 when cut along a plane perpendicular to the Z-axis direction is the same as that when cut along a plane perpendicular to the Z-axis direction. It is larger than the cross-sectional area (second area S2) of the second stacked unit SB2.

  Thereby, for example, when a current is passed through the stacked body SB0 via the first conductive layer 81 and the second conductive layer 82, the current density in the second stacked unit SB2 is larger than the current density in the first stacked unit SB1. can do. The current density in the oscillation layer (sixth magnetic layer 60) can be increased.

  By increasing the current density in the oscillation layer, for example, the magnetization 60m of the sixth magnetic layer 60 can be oscillated (precessed) with a smaller current. With a smaller current, the magnetization 60m can be oscillated. Thereby, for example, the current flowing through the MTJ in the write operation can be reduced.

  For example, the width (the length along the X-axis direction) of the second stacked unit SB2 is desirably 25 nm or less. For example, the first area S1 of the first stacked unit SB1 is desirably 2.0 times or more the second area S2 of the second stacked unit SB2.

FIG. 23 is a schematic cross-sectional view illustrating another nonvolatile memory device according to the first embodiment.
As shown in FIG. 23, the nonvolatile memory device 614 includes a magnetic memory element 118b. The nonvolatile storage device 614 may further include a control unit 550 (not shown in FIG. 23). The magnetic memory element 118 b includes a magnetic shield 51. The stacked body SB0 has a side surface SS0 extending in the Z-axis direction. The first stacked unit SB1 has a side surface SS1 (first side surface) extending in the Z-axis direction. The second stacked unit SB2 has a side surface SS2 (second side surface) extending in the Z-axis direction. The sixth nonmagnetic layer 36 has a side surface SSn extending in the Z-axis direction. Here, “extending in the Z-axis direction” includes a state non-parallel to the Z-axis direction. “Extending in the Z-axis direction” has at least a component extending in the Z-axis direction. The “plane extending in the Z-axis direction” is not orthogonal to the Z-axis direction.

  The magnetic shield 51 overlaps at least a part of the side surface SS0 of the multilayer body SB0. The magnetic shield 51 faces at least a part of the side surface SS0 of the multilayer body SB0. For example, the magnetic shield 51 is in contact with at least a part of the side surface SS0 of the multilayer body SB0. The side surface SS0 of the stacked body SB0 includes, for example, the side surface SS1 (first side surface) of the first stacked unit SB1, the side surface SS2 (second side surface) of the second stacked unit SB2, and the side surface SSn of the sixth nonmagnetic layer 36. ,including. In this example, the magnetic shield 51 covers the side surface SS1, the side surface SS2, and the side surface SSn. The shape of the magnetic shield 51 projected onto the XY plane is, for example, an annular shape surrounding the stacked body SB0.

  The magnetic memory element 118b further includes a protective layer 52. The protective layer 52 is provided between the side surface SS0 of the multilayer body SB0 and the magnetic shield 51. The thickness of the protective layer 52 is substantially the same as or longer than the distance in the Z-axis direction from the center of the second magnetic layer 20 in the Z-axis direction to the center of the sixth magnetic layer 60 in the Z-axis direction. It is desirable. The distance in the Z-axis direction between the center in the Z-axis direction of the second magnetic layer 20 and the center in the Z-axis direction of the sixth magnetic layer 60 is short, for example, in the configuration of the magnetic memory element 118b. The configuration of the magnetic memory element 126 is long. The thickness of the protective layer 52 is desirably 2 nm or more and 30 nm or less, for example. The magnetic shield 51 and the protective layer 52 may be provided in any magnetic memory element according to the embodiment.

  The second nonmagnetic layer 32 overlaps at least a part of the side surface SS1 of the first stacked unit SB1. The second nonmagnetic layer 32 overlaps at least part of the first magnetic layer 10 in the X-axis direction. The second nonmagnetic layer 32 is provided between at least a part of the first magnetic layer 10 and the protective layer 52 in the X-axis direction.

For example, the side surface SS1 of the first stacked unit SB1 and the side surface SS2 of the second stacked unit SB2 are covered with a magnetic shield 51 such as permalloy (Py) via a protective layer 52 such as SiN or Al ₂ O ₃ . Thereby, for example, when a plurality of magnetic memory elements 118b are arranged, the leakage magnetic field from the adjacent magnetic memory element 118b is prevented from adversely affecting the operations of the first stacked unit SB1 and the second stacked unit SB2. Is done. For example, in each memory cell (stacked body SB0), the effective magnetic field acting on the first stacked unit SB1 is substantially the same, so that variation in reversal current between bits is suppressed. The variation in oscillation current is similarly suppressed for the second stacked unit SB2. It is possible to suppress the leakage magnetic field from the first stacked unit SB1 and the second stacked unit SB2 from acting on the adjacent magnetic memory element. As a result, a plurality of magnetic memory elements can be arranged close to each other, and the degree of integration can be improved. For example, the storage density of the nonvolatile storage device is improved.

  For the magnetic shield 51, for example, any metal selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr), or selected from this group Alloys containing two or more metals that are made are used. The magnetic shield 51 includes, for example, at least one metal selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), manganese (Mn), and chromium (Cr), platinum (Pt), An alloy containing at least one metal selected from the group consisting of palladium (Pd), iridium (Ir), ruthenium (Ru), and rhodium (Rh) may be used.

  The characteristics of the magnetic shield 51 can be adjusted by adjusting the composition of the magnetic material contained in the magnetic shield 51 and the conditions of the heat treatment. The magnetic shield 51 may be an amorphous alloy of a rare earth-transition metal such as TbFeCo and GdFeCo. The magnetic shield 51 may have a laminated structure such as Co / Pt, Co / Pd, and Co / Ni.

  The protective layer 52 includes, for example, aluminum (Al), titanium (Ti), zinc (Zn), zirconium (Zr), tantalum (Ta), cobalt (Co), nickel (Ni), silicon (Si), magnesium ( An oxide, nitride, or fluoride containing at least one element selected from the group consisting of Mg) and iron (Fe) can be used. For example, SiN is used for the protective layer 52.

Hereinafter, an example of a method for manufacturing the magnetic memory element 118b illustrated in FIG. 23 will be described.
After forming a lower electrode (not shown) on the wafer, the wafer is placed in an ultra-high vacuum sputtering apparatus. On the lower electrode, Ru / Ta (contact layer and stopper layer with the lower electrode), FePt layer (first magnetic layer 10), MgO (first nonmagnetic layer 31), CoFeB layer (memory layer), and On top of this, a Ru layer (sixth nonmagnetic layer 36) is laminated in this order. Here, the strength of magnetic anisotropy in the direction perpendicular to the film surface of CoFeB and FePt layer / CoFeB can also be adjusted by annealing in a magnetic field. Subsequently, a Py layer / Cu / CoFeB / FePt layer (magnetic field generating portion) and a Ru / Ta layer (upper contact layer) are stacked in this order. Thereby, a processed body is formed.

  Next, an EB resist is applied and EB exposure is performed to form a resist mask having a diameter of 30 nm. The portion not covered with the resist by ion milling is scraped until the Ta layer on the lower electrode that also serves as the stopper layer is exposed.

  Subsequently, after a SiN layer is formed as the protective layer 52, a Py layer that functions as the magnetic shield 51 is formed. The Py layer is left on the side wall of the magnetic memory element by etch back.

Next, a SiO ₂ film for insulatingly embedding the magnetic memory element is formed. Thereby, the magnetic memory element is embedded with insulation. Then, after flattening by CMP or the like, the contact layer with the electrode is exposed by etching the entire surface by RIE or the like.

Further, a resist is applied to the entire surface, and this resist is patterned using a stepper exposure apparatus so that a portion not covered with the resist is formed at the position of the upper electrode. An opening corresponding to the upper electrode is filled with Cu to form a film, and the resist is removed. The upper electrode is provided with a wiring (not shown) so that electrical input / output can be performed.
Thus, the magnetic memory element 614 is formed.

(Second Embodiment)
FIG. 24 is a schematic view illustrating the nonvolatile memory device according to the second embodiment.
As shown in FIG. 24, the nonvolatile memory device 620 according to this embodiment includes a memory cell array MCA. The memory cell array MCA has a plurality of memory cells MC arranged in a matrix. Each of the memory cells MC has one of the magnetic memory elements according to the first embodiment as an MTJ element (stacked body SB0).

  In the memory cell array MCA, a plurality of bit line pairs (bit line BL and bit line / BL) and a plurality of word lines WL are arranged. Each of the plurality of bit line pairs extends in the column direction. Each of the plurality of word lines WL extends in the row (row) direction.

  Memory cells MC are arranged at the intersections between the bit lines BL and the word lines WL. Each of the memory cells MC includes an MTJ element and a selection transistor TR. One end of the MTJ element is connected to the bit line BL. The other end of the MTJ element is connected to the drain terminal of the selection transistor TR. The gate terminal of the selection transistor TR is connected to the word line WL. The source terminal of the selection transistor TR is connected to the bit line / BL.

  A row decoder 621 is connected to the word line WL. A write circuit 622a and a read circuit 622b are connected to the bit line pair (bit line BL and bit line / BL). A column decoder 623 is connected to the writing circuit 622a and the reading circuit 622b.

  Each memory cell MC is selected by a row decoder 621 and a column decoder 623. An example of data writing to the memory cell MC is as follows. First, in order to select a memory cell MC for writing data, a word line WL connected to the memory cell MC is activated. As a result, the selection transistor TR is turned on.

  In this example, for example, the control unit 550 includes the row decoder 621, the write circuit 622a, the read circuit 622b, and the column decoder 623. The control unit 550 is electrically connected to each of a plurality of memory cells MC (a plurality of magnetic memory elements) via the bit line BL, the word line WL, the selection transistor TR, and the like. The control unit 550 performs data writing and data reading in each of the plurality of memory cells MC.

  For example, a bidirectional write current is supplied to the MTJ element. Specifically, when a write current is supplied to the MTJ element from left to right, the write circuit 622a applies a positive potential to the bit line BL and applies a ground potential to the bit line / BL. When supplying a write current from right to left to the MTJ element, the write circuit 622a applies a positive potential to the bit line / BL and applies a ground potential to the bit line BL. In this way, data “0” or data “1” can be written into the memory cell MC.

  An example of reading data from the memory cell MC is as follows. First, the memory cell MC is selected. The read circuit 622b supplies, to the MTJ element, for example, a read current that flows in a direction from the selection transistor TR to the MTJ element. Then, the read circuit 622b detects the resistance value of the MTJ element based on this read current. In this way, information stored in the MTJ element can be read.

FIG. 25 is a schematic view illustrating the nonvolatile memory device according to the second embodiment.
FIG. 25 illustrates a portion of one memory cell MC. In this example, the magnetic memory element 110 and the magnetic memory element 116 are used, but any magnetic memory element according to the embodiment can be used.

  As illustrated in FIG. 25, the nonvolatile memory device 620 includes the magnetic memory element (for example, the magnetic memory element 110 and the magnetic memory element 116) according to the embodiment, the first wiring 91, and the second wiring 92. The first wiring 91 is directly or indirectly connected to one end of the magnetic memory element 110 (for example, the end of the first stacked unit SB1). The second wiring 92 is directly or indirectly connected to one end of the magnetic memory element 116 (for example, the end of the second stacked unit SB2).

  The magnetic memory element included in the nonvolatile memory device 620 is not limited to the magnetic memory element 110 and the magnetic memory element 116, and includes any one of the magnetic memory elements described in the first embodiment.

  Here, “directly connected” includes a state in which other conductive members (for example, via electrodes and wirings) are electrically connected without being inserted therebetween. “Indirectly connected” means a state in which another conductive member (for example, a via electrode or wiring) is inserted and electrically connected, and a switch (for example, a transistor) is inserted in between. Thus, it includes a state where conduction and non-conduction are connected in a variable state.

  One of the first wiring 91 and the second wiring 92 corresponds to, for example, the bit line BL. One of the first wiring 91 and the second wiring 92 corresponds to, for example, the bit line / BL.

  As shown in FIG. 25, the nonvolatile memory device 620 may further include a selection transistor TR. The selection transistor TR is provided at least between the magnetic memory element 110 and the first wiring 91 (first position) and between the magnetic memory element 110 and the second wiring 92 (second position). .

  With such a configuration, data can be written to any memory cell MC (for example, the magnetic memory element 110) of the memory cell array MCA, and data written to the magnetic memory element 110 can be read. Also in the nonvolatile memory device 620 configured as described above, the write current can be reduced by magnetostatically coupling the second magnetic layer 20 and the sixth magnetic layer 60. Thereby, the failure by a dielectric breakdown can be suppressed and reliability improves.

(Third embodiment)
FIG. 26A to FIG. 26C are schematic views illustrating the nonvolatile memory device according to the third embodiment.
FIG. 26A is a perspective view. FIG. 26B is a side view of FIG. FIG. 26C is a top view of FIG.

  Nonvolatile memory device 640 includes select transistor TR, bit line / BL, bit line BL, and MTJ element 150.

  As shown in FIGS. 26A to 26C, the select transistor TR includes a part of the word line WL, a source region Sc, and a drain region Dn. For example, the word line WL extends in the X-axis direction.

  Bit line / BL intersects word line WL. For example, the bit line / BL extends in the Y-axis direction. A part of bit line / BL is electrically connected to contact 400. The contact 400 extends in the Z-axis direction. The contact 400 is electrically connected to a part of the wiring 401. The wiring 401 extends in the X-axis direction. A part of the wiring 401 is electrically connected to the contact 402. The contact 402 extends in the Z-axis direction. Contact 402 is electrically connected to source region Sc.

  The bit line BL intersects with the word line WL. For example, the bit line BL extends in the Y-axis direction. The bit line BL is aligned with the bit line / BL in the X-axis direction.

  One of the magnetic memory elements according to the first embodiment is referred to as an MTJ element 150. For example, the MTJ element 150 includes the second magnetic layer 20 and a wiring 450. The wiring 450 includes the first magnetic layer 10, the third magnetic layer 30, the third nonmagnetic layer 33, and the seventh magnetic layer 70. For example, the wiring 450 extends in the Y-axis direction. The wiring 450 is electrically connected to the bit line BL. For example, the wiring 450 overlaps part of the bit line BL in the Z-axis direction. For example, the wiring may be electrically connected to the bit line BL via the contact 451. The contact 451 extends in the Z-axis direction.

  The second magnetic layer 20 is provided between a part of the wiring 450 and a part of the wiring 460 in the Z-axis direction. The second magnetic layer 20 is connected to the wiring 450 through, for example, a first nonmagnetic layer (not shown). The second magnetic layer 20 is electrically connected to the wiring 460, for example.

  The wiring 460 intersects with the bit line / BL and the bit line BL. The wiring 460 extends in the X-axis direction. A part of the wiring 460 is electrically connected to the contact 461. The contact 461 extends in the Z-axis direction. For example, the contact 461 is aligned with the contact 402 in the Y-axis direction. Contact 461 is electrically connected to a part of drain region Dn.

  According to the embodiment, a highly reliable magnetic memory element and nonvolatile memory device are provided.

In the present specification, “vertical” and “parallel” include not only strict vertical and strict parallel, but also include variations in the manufacturing process, for example, and may be substantially vertical and substantially parallel. .
In the specification of the present application, the state of being stacked includes not only the state of being stacked in direct contact but also the case of being stacked with another element inserted therebetween.

  The embodiments of the present invention have been described above with reference to specific examples. However, embodiments of the present invention are not limited to these specific examples. For example, specific elements of the storage unit, magnetic storage element, control unit, stacked body, magnetization rotation layer, first to fourth magnetic layers, and first to third nonmagnetic layers included in the nonvolatile storage device Concerning configurations, those skilled in the art can appropriately select from the well-known ranges to implement the present invention in the same manner, and are included in the scope of the present invention as long as similar effects can be obtained.

  Combinations of any two or more elements of each specific example within the technically possible range are also included in the scope of the present invention as long as they include the gist of the present invention.

  In addition, all magnetic memory elements and nonvolatile memory devices that can be implemented by those skilled in the art based on the magnetic memory elements and nonvolatile memory devices described above as embodiments of the present invention are also included in the gist of the present invention. As long as it is included in the scope of the present invention.

  In addition, in the category of the idea of the present invention, those skilled in the art can conceive of various changes and modifications, and it is understood that these changes and modifications also belong to the scope of the present invention. .

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... 1st magnetic layer, 10F ... 1st magnetic film, 10L ... Length, 10c ... Area | region, 10d ... Part, 10h ... Recessed part, 10m ... Magnetization, 10s ... Surface, 10w ... Side surface, 18 ... 8th magnetic layer, 18m ... magnetization, 18s ... main surface, 20 ... second magnetic layer, 20F ... second magnetic film, 20L ... length, 20m ... magnetization, 21, 22 ... first and second parts, 21m, 22m ... magnetization, 30 ... 3rd magnetic layer, 30m ... Magnetization, 31 ... 1st nonmagnetic layer, 31F ... 1st nonmagnetic film, 31a ... Area | region, 32 ... 2nd nonmagnetic layer, 32F, 32F2, 32F3 ... 2nd nonmagnetic film, 32a, 32b ... 1st, 2nd partial area, 32h ... Recessed part, 32iw ... Inner side surface, 32t ... Upper surface, 33 ... 3rd nonmagnetic layer, 34 ... 4th nonmagnetic layer, 35 ... 5th nonmagnetic layer, 36 ... 6th nonmagnetic layer, 40 ... 4th magnetism , 40 m: magnetization, 50: fifth magnetic layer, 50 m: magnetization, 50 s: main surface, 51: magnetic shield, 52: protective layer, 60: sixth magnetic layer, 60 m: magnetization, 70: seventh magnetic layer, 70 m ... Magnetization, 72 ... Magnetization, 72a ... Perpendicular magnetization component, 72b ... In-plane magnetization component, 81 ... First conductive layer, 82 ... Second conductive layer, 86A, 86B ... Mask, 86h ... Opening, 87A, 87B ... Mask 87w ... side surface, 91 ... first wiring, 92 ... second wiring, 110, 111, 111A, 111B, 112-118, 118a, 118b, 121-130 ... magnetic memory element, 150 ... MTJ element, 200, 200F, 200F1, 200F2 ... interlayer insulating film, 400, 402, 451, 461 ... contact, 401, 450, 460 ... wiring, 550 ... control unit, 610-614, 620, 640 ... non-volatile memory device, 621 ... row decoder, 622 a ... write circuit, 622 b ... read circuit, 623 ... column decoder, / BL, BL ... bit line, Dn ... drain region, J ... current density , Lx, Ly ... length, MC ... memory cell, MCA ... memory cell array, Pw ... write probability, SB0 ... stacked body, SB1 ... first stacked section, SB2 ... second stacked section, SD1 ... stacked direction, SD2 ... surface Inward direction, SS0, SS1, SS2, SSn ... side face, Sc ... source region, TR ... selection transistor, WL ... word line, e1, e2 ... electron current, e3 ... sense current

According to the embodiment of the present invention, the magnetic memory element includes a first magnetic layer, a second magnetic layer, a first nonmagnetic layer, and a second nonmagnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer. The first direction is a direction from the first magnetic layer toward the second magnetic layer. At least a part of the second nonmagnetic layer overlaps at least a part of the first magnetic layer in a second direction orthogonal to the first direction. The second nonmagnetic layer is electrically connected to the first magnetic layer and includes at least one selected from the group consisting of Ti, V, Nb, Mo, Ru, Pd, Ta, W, and Pt . The magnetization of the first magnetic layer is substantially fixed, and the magnetization direction of the second magnetic layer is variable.
According to the embodiment of the present invention, the magnetic memory element includes a first magnetic layer, a second magnetic layer, a first nonmagnetic layer, and a second nonmagnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer. The second nonmagnetic layer is electrically connected to the first magnetic layer and includes at least one selected from the group consisting of Ti, V, Nb, Mo, Ru, Pd, Ta, W, and Pt. The second nonmagnetic layer has a surface facing the first magnetic layer in a second direction orthogonal to the first direction from the first magnetic layer toward the second magnetic layer. The magnetization of the first magnetic layer is substantially fixed, and the magnetization direction of the second magnetic layer is variable.

Claims (10)

A first magnetic layer;
A second magnetic layer;
A first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer;
A second nonmagnetic layer electrically connected to the first magnetic layer;
With
At least a part of the second nonmagnetic layer overlaps with at least a part of the first magnetic layer in a second direction orthogonal to the first direction from the first magnetic layer toward the second magnetic layer,
The magnetization of the first magnetic layer is substantially fixed;
A magnetic memory element, wherein the direction of magnetization of the second magnetic layer is variable.   2. The magnetic memory element according to claim 1, wherein a magnetization component along the first direction of the first magnetic layer is larger than a magnetization component of the first magnetic layer in the second direction.   The magnetic memory element according to claim 1, wherein the second nonmagnetic layer does not overlap the second magnetic layer in the second direction.   The magnetic memory element according to claim 1, wherein the second nonmagnetic layer is in contact with the first magnetic layer.   5. The length of the first magnetic layer in the third direction intersecting the first direction and the second direction is longer than the length of the first magnetic layer in the second direction. The magnetic memory element according to one. A third magnetic layer provided apart from the second magnetic layer in the third direction;
The third magnetic layer is provided apart from the first magnetic layer in the first direction;
The magnetic memory element according to claim 5, wherein the magnetization direction of the third magnetic layer is variable.   A fourth magnetic layer provided in at least one of the first nonmagnetic layer and the second magnetic layer and between the first nonmagnetic layer and the first magnetic layer in the first direction; The magnetic memory element according to claim 1, further comprising a layer. A fourth magnetic layer provided between the first nonmagnetic layer and the first magnetic layer in the first direction;
In the second direction, at least part of the second nonmagnetic layer overlaps with at least part of the fourth magnetic layer,
The magnetic memory element according to claim 1, wherein the second nonmagnetic layer is electrically connected to the fifth magnetic layer. A first magnetic layer;
A second magnetic layer;
A first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer;
A second nonmagnetic layer electrically connected to the first magnetic layer;
With
The second nonmagnetic layer has a surface facing the first magnetic layer in a second direction orthogonal to the first direction from the first magnetic layer toward the second magnetic layer;
The magnetization of the first magnetic layer is substantially fixed;
A magnetic memory element, wherein the direction of magnetization of the second magnetic layer is variable. A magnetic memory element according to any one of claims 1 to 9,
A controller electrically connected to the magnetic memory element;
A non-volatile storage device.

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