U.S. patent application number 15/661026 was filed with the patent office on 2018-09-20 for magnetic memory device.
The applicant listed for this patent is TOSHIBA MEMORY CORPORATION. Invention is credited to Tsuyoshi Kondo, Michael Arnaud Quinsat, Takuya Shimada.
Application Number | 20180269381 15/661026 |
Document ID | / |
Family ID | 63520297 |
Filed Date | 2018-09-20 |
United States Patent
Application |
20180269381 |
Kind Code |
A1 |
Quinsat; Michael Arnaud ; et
al. |
September 20, 2018 |
MAGNETIC MEMORY DEVICE
Abstract
According to one embodiment, a magnetic memory device includes
first and second magnetic members, and a conductive member. The
first magnetic member includes first, second, and third extending
portions. The first extending portion extends along a first
direction. The second extending portion extends along a second
direction. The third extending portion includes a third connection
portion connected with the first and second extending portions. The
third extending portion extends along a third direction. The
conductive member extends along a fourth direction. The first and
second directions are inclined with respect to the fourth
direction. The conductive member includes a portion overlapping at
least parts of the first and second extending portions in a fifth
direction. The fifth direction crosses the first, the second and
the fourth directions. The conductive member includes a metal. A
direction from the third extending portion toward the second
magnetic member crosses the third direction.
Inventors: |
Quinsat; Michael Arnaud;
(Yokohama Kanagawa, JP) ; Shimada; Takuya;
(Kawasaki Kanagawa, JP) ; Kondo; Tsuyoshi;
(Kawasaki Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOSHIBA MEMORY CORPORATION |
Tokyo |
|
JP |
|
|
Family ID: |
63520297 |
Appl. No.: |
15/661026 |
Filed: |
July 27, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 43/08 20130101;
H01L 43/10 20130101; G11C 11/1673 20130101; G11C 11/1675 20130101;
G11C 19/02 20130101; H01L 43/06 20130101; G11C 11/161 20130101;
G11C 19/0841 20130101; H01L 43/02 20130101 |
International
Class: |
H01L 43/02 20060101
H01L043/02; H01L 43/10 20060101 H01L043/10; H01L 43/08 20060101
H01L043/08; G11C 11/16 20060101 G11C011/16; G11C 19/02 20060101
G11C019/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 16, 2017 |
JP |
2017-051266 |
Claims
1. A magnetic memory device, comprising: a first magnetic member
including a first extending portion, a second extending portion,
and a third extending portion, the first extending portion
extending along a first direction, the second extending portion
extending along a second direction different from the first
direction, the third extending portion including a third connection
portion connected with the first extending portion and the second
extending portion, the third extending portion extending along a
third direction; a conductive member extending along a fourth
direction, the first direction being inclined with respect to the
fourth direction, the second direction being inclined with respect
to the fourth direction, the conductive member including an
overlapping portion, the overlapping portion overlapping at least a
part of the first extending portion and at least a part of the
second extending portion in a fifth direction, the fifth direction
crossing the first direction, the second direction and the fourth
direction, the conductive member including a metal; and a second
magnetic member, a direction from the third extending portion
toward the second magnetic member crossing the third direction.
2. The device according to claim 1, wherein the conductive member
has a first side extending along the fourth direction and a second
side extending along the fourth direction, a position of the first
side in a sixth direction is located between a position of the
third extending portion in the sixth direction and a position of
the second side in the sixth direction, the sixth direction crosses
the first direction, the second direction and the fourth direction,
and the sixth direction is substantially perpendicular to the fifth
direction.
3. The device according to claim 2, wherein the first extending
portion includes a first connection portion and a first end, the
second extending portion includes a second connection portion and a
second end, the first connection portion is connected with the
third connection portion, the second connection portion is
connected with the third connection portion, the first connection
portion is positioned between the third connection portion and the
first end, the second connection portion is positioned between the
third connection portion and the second end, a position of the
first end in the sixth direction is between the position of the
first side in the sixth direction and the position of the second
side in the sixth direction, and a position of the second end in
the sixth direction is between the position of the first side in
the sixth direction and the position of the second side in the
sixth direction.
4. The device according to claim 1, wherein a difference between a
first angle and a second angle is not more than 10 degrees, the
first angle is between the first direction and the fourth
direction, and the second angle is between the second direction and
a reverse direction of the fourth direction.
5. The device according to claim 1, wherein a first angle between
the first direction and the fourth direction is not less than 10
degrees and not more than 80 degrees, and a second angle between
the second direction and a reverse direction of the fourth
direction is not less than 10 degrees and not more than 80
degrees.
6. The device according to claim 1, wherein a difference between a
third angle and a fourth angle is not more than 10 degrees, the
third angle is between the first direction and the third direction,
and the fourth angle is between the second direction and the third
direction.
7. The device according to claim 1, further comprising: a
controller, the conductive member including a first end portion and
a second end portion, the overlapping portion being provided
between the first end portion and the second end portion, a
direction from the second end portion toward the first end portion
is along the fourth direction, the controller being electrically
connected with the first end portion and the second end portion,
the controller being configured to provide a first current to the
conductive member in a first writing operation and to provide a
second current to the conductive member in a second writing
operation, a direction of the first current being from the first
end portion toward the second end portion, a direction of the
second current being from the second end portion toward the first
end portion, a first state formed in the third extending portion in
the first writing operation is different from a second state formed
in the third extending portion in the second writing operation.
8. The device according to claim 1, further comprising: a
controller, the conductive member including a first end portion and
a second end portion, the overlapping portion being provided
between the first end portion and the second end portion, a
direction from the first end portion toward the second end portion
is along the fourth direction, the overlapping portion including: a
first overlapping region overlapping the at least the part of the
first extending portion in the fifth direction; and a second
overlapping region overlapping the at least the part of the second
extending portion in the fifth direction, the conductive member
including an intermediate region located between the first
overlapping region and the second overlapping region, the
controller being electrically connected with the first end portion,
the second end portion and the intermediate region, the controller
being configured to make a first electric potential of the first
end portion higher than a third electric potential of the
intermediate region in a first writing operation and to make a
second electric potential of the second end portion lower than the
third electric potential in the first writing operation, to make
the first electric potential lower than the third electric
potential in a second writing operation and to make the second
electric potential higher than the third electric potential in the
second writing operation, a first state formed in the third
extending portion in the first writing operation being different
from a second state formed in the third extending portion in the
second writing operation.
9. The device according to claim 7, wherein the third extending
portion further includes a third end portion, the third connection
portion is positioned between the first connection portion and the
third end portion, the controller is further electrically connected
with the third end portion, the controller is configured to supply
a third current flowing between the third end portion and the
conductive member in a shift operation.
10. The device according to claim 7, wherein the controller is
further electrically connected with the second magnetic member, the
controller is configured to output either one of a first signal and
a second signal in a reading operation, the first signal is
outputted after the first writing operation is performed, the
second signal is outputted after the second writing operation is
performed, and the first signal is different from the second
signal.
11. The device according to claim 1, wherein the overlapping
portion physically contacts the at least the part of the first
extending portion and the at least the part of the second extending
portion.
12. The device according to claim 1, wherein the metal includes at
least one selected from the group consisting of Tantalum and
Tungsten.
13. The device according to claim 1, wherein the metal includes at
least one selected from the group consisting of Platinum and
Gold.
14. The device according to claim 1, wherein the third direction is
along the fifth direction.
15. The device according to claim 1, wherein the third extending
portion has a pipe configuration extending along the third
direction.
16. The device according to claim 1, further comprising: a
substrate having a face, the conductive member being provided on
the face, the at least the part of the first extending portion and
the at least the part of the second extending portion being
provided on the conductive member, the third extending portion
being provided on a part of the at least the part of the first
extending portion and a part of the at least the part of the second
extending portion, and the third direction being substantially
perpendicular to the face.
17. The device according to claim 1, further comprising: an
intermediate member being provided between the second magnetic
member and the third extending portion.
18. The device according to claim 17, wherein the intermediate
member includes a magnesium oxide.
19. The device according to claim 1, wherein the first magnetic
member includes at least one selected form the group consisting of
Iron, Cobalt, and Nickel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2017-051266, filed on
Mar. 16, 2017; the entire contents of which are incorporated herein
by reference.
FIELD
[0002] The embodiment of the present invention is generally related
to a magnetic memory device.
BACKGROUND
[0003] There is a magnetic memory device including the magnetic
shift register using a magnetic body. The stable operation in the
magnetic memory device is demanded.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1A to FIG. 1D are schematic views illustrating a
magnetic memory device according to a first embodiment;
[0005] FIG. 2A and FIG. 2B are schematic views illustrating
operations in the magnetic memory device according to the first
embodiment;
[0006] FIG. 3A and FIG. 3B are schematic perspective views
illustrating operations in a magnetic memory device;
[0007] FIG. 4A and FIG. 4B are schematic perspective views
illustrating operations in a magnetic memory device;
[0008] FIG. 5 is a schematic perspective view illustrating
operations in a magnetic memory device;
[0009] FIG. 6A to FIG. 6D are schematic views illustrating
operations in the magnetic memory device according to the first
embodiment;
[0010] FIG. 7A and FIG. 7B are schematic views illustrating other
operations in the magnetic memory device according to the first
embodiment;
[0011] FIG. 8A and FIG. 8B are schematic views illustrating other
operations in the magnetic memory device according to the first
embodiment;
[0012] FIG. 9A and FIG. 9B are schematic views illustrating other
operations in the magnetic memory device according to the first
embodiment;
[0013] FIG. 10 is a schematic sectional view illustrating another
magnetic memory device according to the first embodiment;
[0014] FIG. 11 is a schematic sectional view illustrating another
magnetic memory device according to the first embodiment;
[0015] FIG. 12 is a schematic plan view illustrating another
magnetic memory device according to the first embodiment;
[0016] FIG. 13 is a schematic plan view illustrating another
magnetic memory device according to the first embodiment;
[0017] FIG. 14A and FIG. 14B are schematic views illustrating
operations in the other magnetic memory device according to the
first embodiment;
[0018] FIG. 15A and FIG. 15B are schematic views illustrating other
operations in the other magnetic memory device according to the
first embodiment;
[0019] FIG. 16A and FIG. 16B are schematic views illustrating other
operations in the other magnetic memory device according to the
first embodiment;
[0020] FIG. 17A and FIG. 17B are schematic views illustrating other
operations in the other magnetic memory device according to the
first embodiment; and
[0021] FIG. 18 is a schematic perspective view illustrating a
magnetic memory device according to a second embodiment.
DETAILED DESCRIPTION
[0022] According to one embodiment, a magnetic memory device
includes a first magnetic member, a conductive member, and a second
magnetic member. The first magnetic member includes a first
extending portion, a second extending portion, and a third
extending portion. The first extending portion extends along a
first direction. The second extending portion extends along a
second direction different from the first direction. The third
extending portion includes a third connection portion connected
with the first extending portion and the second extending portion.
The third extending portion extends along a third direction. The
conductive member extends along a fourth direction. The first
direction is inclined with respect to the fourth direction. The
second direction is inclined with respect to the fourth direction.
The conductive member includes an overlapping portion. The
overlapping portion overlaps at least a part of the first extending
portion and at least a part of the second extending portion in a
fifth direction. The fifth direction crosses the first direction,
the second direction and the fourth direction. The conductive
member includes a metal. A direction from the third extending
portion toward the second magnetic member crosses the third
direction.
[0023] Various embodiments will be described hereinafter with
reference to the accompanying drawings.
[0024] The drawings are schematic and conceptual; and the
relationships between the thickness and width of portions, the
proportions of sizes among portions, etc., are not necessarily the
same as the actual values thereof. Further, the dimensions and
proportions may be illustrated differently among drawings, even for
identical portions.
[0025] In the present specification and drawings, the same elements
as those described previously with reference to earlier figures are
labeled with like reference numerals, and the detailed description
thereof is omitted as appropriate.
First Embodiment
[0026] FIG. 1A to FIG. 1D are schematic views illustrating a
magnetic memory device according to a first embodiment.
[0027] FIG. 1A is a plan view seen from the arrow AA of FIG. 1B.
FIG. 1B is an A1-A2 line sectional view of FIG. 1A. FIG. 1C is a
B1-B2 line sectional view of FIG. 1A. FIG. 1D is a schematic view
showing angles.
[0028] As shown in these figures, the magnetic memory device 110
according to the embodiment includes a first magnetic member 10, a
conductive member 50, and a second magnetic member 20. In this
example, the magnetic memory device 110 further includes a
controller 70. The first magnetic member 10, the conductive member
50, and the second magnetic member 20 are included in an element
portion 10E. The element portion 10E corresponds to a memory part.
The controller 70 controls the element portion 10E.
[0029] The first magnetic member 10 includes a first extending
portion 11, a second extending portion 12, and a third extending
portion 13. The first extending portion 11 extends along a first
direction D1. The second extending portion 12 extends along a
second direction D2. The second direction D2 differs from the first
direction D1. The third extending portion 13 includes a third
connection portion 13C. The third connection portion 13C is
connected with the first extending portion 11 and the second
extending portion 12. The third extending portion 13 extends along
a third direction D3.
[0030] For example, the third extending portion 13 further includes
a third end portion 13E. A direction connecting the third end
portion 13E and the third connection portion 13C is along the third
direction D3.
[0031] For example, the first extending portion 11 includes a first
connection portion 11C and a first end 11E. For example, the second
extending portion 12 includes a second connection portion 12C and a
second end 12E. The first connection portion 11C is connected with
the third connection portion 13C. The second connection portion 12C
is connected with the third connection portion 13C. The first
connection portion 11C is located between the third connection
portion 13C and the first end 11E. The second connection portion
12C is located between the third connection portion 13C and the
second end 12E. The third connection portion 13C is located between
the first connection portion 11C and the third end portion 13E. The
third connection portion 13C is located between the second
connection portion 12C and the third end portion 13E.
[0032] The conductive member 50 extends in a fourth direction D4.
The first direction D1 is inclined with respect to the fourth
direction D4. The second direction D2 is inclined with respect to
the fourth direction D4. The conductive member 50 includes an
overlapping portion 55.
[0033] As shown in FIG. 1A and FIG. 1C, the overlapping portion 55
overlaps at least a part of the first extending portion 11 in a
fifth direction D5. The overlapping portion 55 overlaps at least a
part of the second extending portion 12 in the fifth direction D5.
The fifth direction D5 crosses the first direction D1, the second
direction D2, and the fourth direction D4.
[0034] Thus, the overlapping portion 55 includes a first
overlapping region 55a and a second overlapping region 55b. The
first overlapping region 55a overlaps at least a part of the first
extending portion 11 in the fifth direction D5. The second
overlapping region 55b overlaps at least a part of the second
extending portion 12 in the fifth direction D5.
[0035] For example, a direction perpendicular to the first
direction D1 and the second direction D2 is taken as a Z-axis
direction. A direction perpendicular to the Z-axis direction is
taken as an X-axis direction. A direction perpendicular to the
Z-axis direction and the X-axis direction is taken as a Y-axis
direction.
[0036] The fifth direction D5 is along the Z-axis direction, for
example. In this example, the third direction D3 is along an X-Y
plane. In this example, the fourth direction D4 is along the X-Y
plane.
[0037] The conductive member 50 includes a metal. As mentioned
below, a magnetic action works between the conductive member 50 and
the first extending portion 11, for example. For example, a
magnetic action works between the conductive member 50 and the
second extending portion 12. For example, when a current flows in
the conductive member 50, magnetic characteristic in at least one
of the first extending portion 11 and the second extending portion
12 changes. For example, a magnetization direction changes. The
change of the magnetization is transferred to the third extending
portion 13. The magnetization is held in the third extending
portion 13. The third extending portion 13 functions as a shift
register, for example. Information is held at the third extending
portion 13. For example, the first extending portion 11 and the
second extending portion 12 function as a writing part of
information. For example, information is written in the first
extending portion 11 or in the second extending portion 12 by the
conductive member 50.
[0038] As shown in FIG. 1B, the second magnetic member 20 opposes
the third extending portion 13. A direction from the third
extending portion 13 toward the second magnetic member 20 crosses
the third direction D3. In this example, the second magnetic member
20 is apart from the third extending portion 13 along the Z-axis
direction.
[0039] In this example, an intermediate member 22 is provided
between the second magnetic member 20 and the third extending
portion 13. The intermediate member 22 is non-magnetic, for
example. The intermediate member 22 includes MgO, for example.
[0040] The second magnetic member 20, the intermediate member 22,
and a part of the third extending portion 13 form an MTJ (Magnetic
Tunnel Junction), for example. The second magnetic member 20 and
the intermediate member 22 function as at least a part of a reading
part 20U, for example. For example, the characteristic (for
example, electrical resistance) of the reading part 20U changes
depending on the magnetic characteristic of the third extending
portion 13.
[0041] In the magnetic memory device 110 according to the
embodiment, the first extending portion 11 and the second extending
portion 12 are provided. These two portions function as a writing
part. The directions in which these two portions extend are
different from each other. Thereby, as mentioned later, the writing
of first information and second information can be performed
stably.
[0042] As shown in FIG. 1A, the first extending portion 11 and the
second extending portion 12 overlap the overlapping portion 55 in
the Z-axis direction. On the other hand, in this example, the third
connection portion 13C does not overlap the overlapping portion 55
in the Z-axis direction. Thereby, the conductive member 50 does not
affect the magnetization of the third connection portion 13C
substantially, for example. In addition, the conductive member 50
affects the magnetization of the first extending portion 11, or the
magnetization of the second extending portion 12, for example.
Thereby, more stable writing operation can be performed.
[0043] As shown in FIG. 1D, a first angle .theta.1 is taken as an
angle between the first direction D1 and the fourth direction D4. A
second angles .theta.2 is taken as an angle between the second
direction D2 and an opposite direction of the fourth direction
D4.
[0044] In the embodiments, these angles (absolute value of an
angle) may be substantially the same as each other. For example, a
difference of the first angle .theta.1 and the second angle
.theta.2 is not more than 10 degrees. For example, the difference
of the absolute value of the first angle .theta.1 and the absolute
value of the second angle .theta.2 is not more than 10 degrees.
[0045] For example, the absolute value of the first angle .theta.1
is not less than 10 degrees and not more than 80 degrees. For
example, the absolute value of the second angle .theta.2 is not
less than 10 degrees and not more than 80 degrees. For example, the
absolute value of the first angle .theta.1 may be not less than 30
degrees and not more than 60 degrees. For example, the absolute
value of the second angle .theta.2 may be not less than 30 degrees
and not more than 60 degrees.
[0046] For example, a third angle .theta.3 is taken as an angle
between the first direction D1 and the third direction D3. A fourth
angle .theta.4 is taken as an angle between the second direction D2
and the third direction D3. For example, these angles (absolute
value of angle) may be substantially the same as each other. For
example, a difference of the third angle .theta.3 and the fourth
angle .theta.4 is not more than 10 degrees. For example, the
absolute value of the third angle .theta.3 may be not less than 30
degrees and not more than 60 degrees. For example, the absolute
value of the fourth angle .theta.4 may be not less than 30 degrees
and not more than 60 degrees.
[0047] As shown in FIG. 1A, the conductive member 50 has a first
side 51 and a second side 52. The first side 51 extends along the
fourth direction D4. The second side 52 extends along the fourth
direction D4. The second side 52 is an outside side, for
example.
[0048] For example, a sixth direction D6 crosses the first
direction D1, the second direction D2, and the fourth direction D4.
The sixth direction D6 is substantially perpendicular to the fifth
direction D5. For example, an angle between the sixth direction D6
and the fifth direction D5 is not less than 85 degrees and not more
than 95 degrees. The sixth direction D6 is along the X-axis
direction, for example.
[0049] As shown in FIG. 1A, in this example, the position in the
sixth direction D6 of the first side 51 is located between the
position in the sixth direction D6 of the third extending portion
13 and the position in the sixth direction D6 of the second side
52, for example.
[0050] For example, the position in the sixth direction D6 of the
first end 11E is located between the position in the sixth
direction D6 of the first side 51 and the position in the sixth
direction D6 of the second side 52. The position in the sixth
direction D6 of the second end 12E is located between the position
in the sixth direction D6 of the first side 51 and the position in
the sixth direction D6 of the second side 52.
[0051] As shown in FIG. 1B, in this example, the second magnetic
member 20 is provided on the third extending portion 13 (first
magnetic member 10). The conductive member 50 is provided under the
first magnetic member 10. For example, the position in the fifth
direction D5 of the first magnetic member 10 is located between the
position in the fifth direction D5 of the second magnetic member 20
and the position in the fifth direction D5 of the conductive member
50.
[0052] As shown in FIG. 1A, the conductive member 50 includes a
first end portion 50a and a second end portion 50b. The overlapping
portion 55 is located between the first end portion 50a and the
second end portion 50b. A direction from the second end portion 50b
toward the first end portion 50a is along the fourth direction
D4.
[0053] In this example, a first electrode E1, a second electrode
E2, a third electrode E3, and a fourth electrode E4 are provided.
The first electrode E1 is electrically connected with the first end
portion 50a. The second electrode E2 is electrically connected with
the second end portion 50b. The third electrode E3 is electrically
connected with the third end portion 13E. The fourth electrode E4
is electrically connected with the second magnetic member 20. The
controller 70 is electrically connected with these electrodes, for
example. Thereby, for example, the controller 70 is electrically
connected with the first end portion 50a and the second end portion
50b. For example, the controller 70 is electrically connected with
the third end portion 13E. For example, the controller 70 is
electrically connected with the second magnetic member 20.
[0054] Hereinafter, examples of operations in the magnetic memory
device 110 are described. The following operations are performed by
the controller 70.
[0055] FIG. 2A and FIG. 2B are schematic views illustrating the
operation in the magnetic memory device according to the first
embodiment.
[0056] FIG. 2A corresponds to a first writing operation WO1. FIG.
2B corresponds to a second writing operation WO2. The first writing
operation WO1 corresponds to writing of the information of "0", for
example. The second writing operation WO2 corresponds to writing of
the information of "1", for example. The first writing operation
WO1 may correspond to the writing of the information of "1", and
the second writing operation WO2 may correspond to the writing of
the information of "0."
[0057] As shown in FIG. 2A, the controller 70 supplies a first
current I1 to the conductive member 50 in first writing operation
WO1. As shown in FIG. 2B, the controller 70 supplies a second
current I2 to the conductive member 50 in the second writing
operation WO2.
[0058] In this example, a direction of the first current I1 is from
the first end portion 50a toward the second end portion 50b. A
direction of the second current I2 is from the second end portion
50b toward the first end portion 50a.
[0059] For example, in the first writing operation WO1, the first
electrode E1 is set at a high potential VH. In the first writing
operation WO1, the second electrode E2 is set at a low potential
VL. The low potential VL is lower than the high potential VH. On
the other hand, in the second writing operation WO2, the first
electrode E1 is set at the low potential VL. In the second writing
operation WO2, the second electrode E2 is set at the high potential
VH.
[0060] In these writing operations, a potential of the third
electrode E3 is arbitrary. For example, the third electrode E3 may
be at a floating potential VF3. In these writing operations, a
potential of the fourth electrode E4 is arbitrary. For example, the
fourth electrode E4 may be at a floating potential VF4.
[0061] A first state formed in the third extending portion 13 in
the first writing operation WO1 differs from a second state formed
in the third extending portion 13 in the second writing operation
WO2.
[0062] For example, a first magnetization is formed in the third
extending portion 13 in the first writing operation WO1. On the
other hand, a second magnetization is formed in the third extending
portion 13, for example, in the second writing operation WO2. The
second magnetization differs from the first magnetization. For
example, the first magnetization is either "upward" or "downward."
The second magnetization is another of "upward" and "downward."
These different magnetizations correspond to the information
memorized.
[0063] In the embodiments, the above-mentioned first current I1 and
the second current I2 act onto the first extending portion 11 and
the second extending portion 12, such action being induced by spin
hall effect occurring in the conductive member 50, for example.
Thereby, magnetic domains are transferred to the third extending
portion 13 from either the first extending portion 11 or the second
extending portion 12. In the embodiment, the directions (the first
direction D1 and the second direction D2) where the first extending
portion 11 and the second extending portion 12 extend are inclined
with respect to the fourth direction D4 where the conductive member
50 extends. In addition, the first direction D1 differs from the
second direction D2. Therefore, for example, the flow of the
magnetic domain generated in the first extending portion 11 differs
from the flow of the magnetic domain generated in the second
extending portion 12. Therefore, either of the first extending
portion 11 or the second extending portion 12 becomes to have a
priority. Thereby, magnetic domains can be stably transferred to
the third extending portion 13.
[0064] Thereby, the writing operation becomes stable. According to
embodiment, the magnetic memory device in which the stable
operation is possible can be provided.
[0065] Hereinafter, an example of moving of the magnetic domain in
a magnetic member extending along one direction will be
described.
[0066] FIG. 3A and FIG. 3B are schematic perspective views
illustrating operations in a magnetic memory device.
[0067] A magnetic member 61 and a conductor 65 are provided. The
conductor 65 extends along a direction D65. The magnetic member 61
is provided on the conductor 65. The magnetic member 61 extends
along a direction D61 from one end 61E to other one end 61F. The
direction D61 is inclined with respect to the direction D65. A
difference of the direction D61 and the direction D65 is taken as a
tilt angle .theta.t.
[0068] As shown in FIG. 3A, the magnetic member 61 has a plurality
of magnetic domains (a first magnetic domain 61a, a second magnetic
domain 61b, a third magnetic domain 61c, etc.). A first magnetic
domain wall 62a is located between the first magnetic domain 61a
and the second magnetic domain 61b. A second magnetic domain wall
62b is located between the second magnetic domain 61b and the third
magnetic domain 61c. For example, a magnetization 61aM in the first
magnetic domain 61a and a magnetization 61cM in the third magnetic
domain 61c are upward. On the other hand, a magnetization 61bM in
the second magnetic domain 61b is downward.
[0069] A current Ic1 flows in the conductor 65. The current is
along the direction D65. By the current Ic1 flowing in the
conductor 65, spin orbit torque occurs on the magnetization of the
magnetic member 61, for example. Thereby, the magnetic domain walls
of the magnetic member 61 move. The motion direction of the
magnetic domain walls in the magnetic member follows the direction
of each of the currents Ic1. The current Ic1 moves the magnetic
domain walls in the direction D61 toward the other one end 61F. At
this time, the moving velocities of the magnetic domain walls
differs between the first magnetic domain wall 62a and the second
magnetic domain wall 62b.
[0070] As shown in FIG. 3A, for example, when the current flows,
the second magnetic domain wall 62b does not move substantially. On
the other hand, the first magnetic domain wall 62a moves toward the
second magnetic domain wall 62b at a high velocity. For example,
the second magnetic domain wall 62b moves, the second magnetic
domain 61b vanishes, and the first magnetic domain 61a and the
third magnetic domain 61c are combined. The magnetizarion of the
magnetic domain at the other one end 61F is oriented downward.
[0071] In an example shown in FIG. 3B, the magnetic member 61 has
the second magnetic domain 61b, the third magnetic domain 61c, and
a fourth magnetic domain 61d. A third magnetic domain wall 62c is
located between the third magnetic domain 61c and the fourth
magnetic domain 61d. A magnetization 61dM in the fourth magnetic
domain 61d is downward. In such configuration, when the current Ic1
flows, the third magnetic domain wall 62c does not move
substantially. On the other hand, the second magnetic domain wall
62b moves towards the other one end 61F at a high velocity. As a
result, the magnetization at the other one end 61F is changed to
orient upward.
[0072] Thus, in both cases of the case shown in FIG. 3A and the
case shown in FIG. 3B, after the current Ic1 has flown in the
direction D65, the magnetization becomes upward at the other one
end 61F. That is, independently to the prior orientation of
magnetization of the first magnetic domain 61a, the second magnetic
domain 61b, the third magnetic domain 61c and the fourth magnetic
domain 61d, the magnetization is controlled to be upward at the
other one end 61F. In an other hand, the magnetization orientation
at the one end 61E depends on the original magnetization
orientation. For example, the magnetization orientation at the one
end 61E is upward in the example shown in FIG. 3A, and downward in
the example shown in FIG. 3B.
[0073] FIG. 4A and FIG. 4B are schematic perspective views
illustrating operations in a magnetic memory device.
[0074] In examples shown in FIG. 4A and FIG. 4B, a direction of the
current flown is reverse with respect to that in examples shown in
FIG. 3A and FIG. 3B. The orientation of a current Ic2 is in a
reverse direction D65r opposite to the direction D65.
[0075] By the current Ic2 flowing in the conductor 65, spin orbit
torque occurs on the magnetization of the magnetic member 61, for
example. The current Ic2 moves the magnetic domain walls in the
direction D61 toward the one end 61E. At this time, the moving
velocities of the magnetic domain walls differs between the first
magnetic domain wall 62a and the second magnetic domain wall
62b.
[0076] As shown in FIG. 4A, for example, when the current Ic2
flows, the second magnetic domain wall 62b does not move
substantially. On the other hand, the first magnetic domain wall
62a moves toward the second magnetic domain 62b at a high velocity.
For example, the second magnetic domain 61b vanishes and the first
magnetic domain 61a and the third magnetic domain 61c are combined.
As a result, the magnetization of the magnetic domain at the one
end 61E is oriented upward.
[0077] On the other hand, in the example shown in FIG. 4B, the
magnetic member 61 has the second magnetic domain 61b, the third
magnetic domain 61c, and the fourth magnetic domain 61d. In such
configuration, when the current Ic2 flows, the second magnetic
domain wall 62b does not move substantially. On the other hand, the
third magnetic domain wall 62c moves toward the one end 61E at a
high velocity. For example, the fourth magnetic domain 61d
vanishes. As a result, the magnetization at the one end 61E is
changed to orient downward.
[0078] Thus, in both cases of the case shown in FIG. 4A and the
case shown in FIG. 4B, after the current Ic2 has flown in the
reverse direction D65r, the magnetization becomes upward at the one
end 61E. That is, independently to the prior orientation of
magnetization of the first magnetic domain 61a, the second magnetic
domain 61b, the third magnetic domain 61c and the fourth magnetic
domain 61d, the magnetization is controlled to be upward at the one
end 61E. In an other hand, the magnetization orientation at the one
other end 61F depends on the original magnetization orientation.
For example the magnetization orientation at the one other end 61F
is upward in the example shown in FIG. 4A, and downward in the
example shown in FIG. 4B.
[0079] FIG. 5 is a schematic perspective view illustrating
operations in a magnetic memory device.
[0080] The conductor 65 extends along the direction D65. A magnetic
member 63 extends along a direction D63 from one end 63E to other
one end 63F. The direction D63 is inclined with respect to the
direction D65. A difference of the direction D63 and the direction
D65 is taken as a tilt angle -.theta.t. The tilt angle -.theta.t is
opposite angle with respect to the tilt angle .theta.t (see FIG.
4B, for example).
[0081] In the example shown in FIG. 5, the magnetic member 63 has a
plurality of magnetic domains (a first magnetic domain 63a, a
second magnetic domain 63b, a third magnetic domain 63c, etc.). A
first magnetic domain wall 64a is located between the first
magnetic domain 63a and the second magnetic domain 64b. A second
magnetic domain wall 64b is located between the second magnetic
domain 63b and the third magnetic domain 63c. In the example shown
in FIG. 5, for example, a magnetization 63aM in the first magnetic
domain 63a and a magnetization 63cM in the third magnetic domain
63c are upward. On the other hand, a magnetization 63bM in the
second magnetic domain 63b is downward.
[0082] In such configuration, the current Ic2 of the reverse
direction D65r flows in the conductor 65. The first magnetic domain
wall 64a does not move substantially. The second magnetic domain
wall 64b moves toward the other one end 63F at a high velocity. As
a result, the magnetization at the other one end 63F is changed to
orient downward.
[0083] For example, the configuration shown in FIG. 4A and the
configuration shown in FIG. 5 are combined. The direction D61 which
is the extending direction of the magnetic member 61 and the
direction D63 of the extending direction of the magnetic member 63
are inclined with respect to the direction D65 which is the
extending direction of the conductor 65. Then, the direction D61
and the direction D63 are opposite to each other. By such
configuration, the direction of the magnetization can be controlled
stably at an end of the magnetic member 61 and at an end of the
magnetic member 63.
[0084] For example, the first extending portion 11 corresponds to
the magnetic member 63. The first connection portion 11C
corresponds to the other one end 63F. For example, the second
extending portion 12 corresponds to the magnetic member 61. The
second connection portion 12C corresponds to the other one end
61F.
[0085] The difference of such moving velocity, described with
regard to FIG. 3A, FIG. 3B, FIG. 4A, FIG. 4B and, FIG. 5, changes
depending on the tilt angle .theta.t. For example, when the tilt
angle .theta.t is about 45 degrees, a large difference occurs in
the moving velocity. For example, when the tilt angle .theta.t is 0
degrees or 90 degrees, a difference is not generated in the moving
velocity.
[0086] For example, for the configuration shown in FIG. 3A, FIG.
3B, FIG. 4A, and FIG. 4B, a first reference example is conceivable
in which the direction D61 is parallel to the direction D65. In the
first reference example, the magnetic domain wall moving velocities
of mutually same grade are given to the magnetic member 61.
Therefore, upward magnetization or downward magnetization is
written in the magnetic member 61 at the location of the other one
end 61F by same grade with the current Ic1. Therefore, the control
of the magnetization direction at the other one end 61F is not
obtained by the supplying of the current Ic1. Upward magnetization
or downward magnetization is written in the magnetic member 61 at
the location of the one end 61E by same grade with the current Ic2.
Therefore, the control of the magnetization direction at the one
end 61E is not obtained by the supplying of the current Ic2.
[0087] For example, for the configuration shown in FIG. 5, a second
reference example is conceivable in which the direction D63 is
parallel to the direction D65. In the second reference example, the
domain wall moving velocities of mutually same grade are given to
the magnetic member 63. Therefore, upward magnetization or downward
magnetization is written in the magnetic member 63 at the location
of the one end 63E by same grade with the current Ic2. Therefore,
the control of the magnetization direction at the one end 63E is
not obtained by the supplying of the current Ic2.
[0088] In embodiment, the first extending portion 11 extends along
the first direction D1. The second extending portion 12 extends
along the second direction D2. The conductive member 50 extends
along the fourth direction D4. In addition, the first direction D1
is inclined with respect to the fourth direction D4. The second
direction D2 is inclined with respect to the fourth direction D4.
For example, the above-mentioned tilt angle .theta.t is larger than
0 degrees and smaller than 90 degrees. Therefore, a difference
occurs in the moving velocity of the magnetic domain walls.
[0089] For example, when a current is supplied in the conductive
member 50, the characteristic of the movement of the magnetic
domain wall in the first extending portion 11 differs from the
characteristic of the movement of the magnetic domain wall in the
second extending portion 12. The movement of the magnetic domain
wall in the first extending portion 11 and the movement of the
magnetic domain wall in the second extending portion 12 are
different from each other, for example. Either of the movement of
the magnetic domain wall in the first extending portion 11 or the
movement of the magnetic domain wall in the second extending
portion 12 is transferred to the third extending portion 13 with
the priority. The transfer of the movement of the magnetic domain
wall of the two extending portions can be selected by the direction
of the current, for example, as described with regard to FIG. 3A,
FIG. 3B, FIG. 4A), FIG. 4B, and FIG. 5.
[0090] FIG. 6A to FIG. 6D are schematic views illustrating
operations in the magnetic memory device according to the first
embodiment.
[0091] FIG. 6A illustrates a state prior to the first writing
operation WO1. FIG. 6B illustrates a state after the first writing
operation WO1. FIG. 6C illustrates a state prior to the second
writing operation WO2. FIG. 6D illustrates a state after the second
writing operation WO2.
[0092] As shown in FIG. 6A, the first current I1 flows. For
example, the magnetic domain wall 11b of the first extending
portion 11 moves toward the third extending portion 13 and the
second extending portion 12. The magnetic domain wall 13b can be
formed in the third extending portion 13, for example (see FIG.
6B). The magnetic domain wall 12b can be formed in the second
extending portion 12, for example. The magnetic domain wall 12b of
the second extending portion 12 moves in a direction away from the
third extending portion 13. For example, the magnetization of the
first extending portion 11 is transferred to the third extending
portion 13.
[0093] Thereby, as shown in FIG. 6B, "downward" magnetization is
written in the third extending portion 13.
[0094] On the other hand, as shown in FIG. 6C, the second current
I2 flows. For example, the magnetic domain wall 12a of the second
extending portion 12 moves toward the third extending portion 13
and the first extending portion 11. The magnetic domain wall 13a
can be formed in the third extending portion 13, for example (see
FIG. 6D). The magnetic domain wall 11a can be formed in the first
extending portion 11, for example. The magnetic domain wall 11a of
the first extending portion 11 moves in a direction away from the
third extending portion 13. For example, the magnetization of the
second extending portion 12 is transferred to the third extending
portion 13.
[0095] Thereby, as shown in FIG. 6D, "upward" magnetization is
written in the third extending portion 13.
[0096] Thus, mutually different magnetizations can be transferred
to the third extending portion 13 by mutually different orientation
currents. By mutually different orientation currents, mutually
different information (0 or 1) can be written in the third
extending portion 13. The initial presence of magnetic domain wall
11b or 11a is not a requirement since such magnetic domain wall is
created during the supplying of the electrical current.
[0097] As already described, for example, a reference example is
conceivable in which the first direction D1 and the second
direction D2 are parallel to the fourth direction D4. In this
reference example, the magnetic properties of mutually same grade
are given to the third extending portion 13 from two extending
portions. Therefore, upward magnetization or downward magnetization
is written in the third extending portion 13 by same grade.
Therefore, the writing is not stabilized.
[0098] On the other hand, in the embodiments, the first direction
D1 and the second direction D2 are inclined with respect to the
fourth direction D4. Thereby, the writing can be performed from
either the first extending portion 11 or the second extending
portion 12 with priority. A stable writing operation can be
performed.
[0099] Hereinafter, examples of a shift operation is described.
[0100] FIG. 7A and FIG. 7B are schematic views illustrating other
operations in the magnetic memory device according to the first
embodiment.
[0101] These figures illustrate two shift operations.
[0102] As shown in FIG. 7A and FIG. 7B, the third extending portion
13 has the third end portion 13E. The third connection portion 13C
is located between the first connection portion 11C and the third
end portion 13E. The third connection portion 13C is located
between the second connection portion 12C and the third end portion
13E. The controller 70 is electrically connected with the third end
portion 13E. In this example, the controller 70 is electrically
connected to the third electrode E3.
[0103] The controller 70 supplies a third current I3 in a shift
operation SO. The third current I3 flows between the third end
portion 13E and the conductive member 50.
[0104] In the example of FIG. 7A, the third current I3 flows from
the conductive member 50 toward the third end portion 13E. In the
example of FIG. 7B, the third current I3 flows from the third end
portion 13E toward the conductive member 50.
[0105] In the example of FIG. 7A, the first electrode E1 and the
second electrode E2 are set at the high potential VH. The third
electrode E3 is set at the low potential VL. In the example of FIG.
7B, the first electrode E1 and the second electrode E2 are set at
the low potential VL. The third electrode E3 is set at the high
potential VH. In these shift operations, the potential of the
fourth electrode E4 is arbitrary. For example, the fourth electrode
E4 may be at the floating potential VF4. By such shift operations,
information (the magnetization) held in the third extending portion
13 shifts in the third extending portion 13 along the third
direction D3.
[0106] Hereinafter, examples of a reading operation are
described.
[0107] FIG. 8A, FIG. 8B, FIG. 9A, and FIG. 9B are schematic views
illustrating other operations in the magnetic memory device
according to the first embodiment.
[0108] As already described, the controller 70 is electrically
connected with the second magnetic member 20. For example, the
controller 70 is electrically connected with the fourth electrode
E4. In a reading operation RO, a fourth current I4 is detected in
the controller 70. The fourth current I4 flows in a current path
including the second magnetic member 20 and the third extending
portion 13.
[0109] In the example of FIG. 8A, the fourth current I4 flows from
the fourth electrode E4 toward the third electrode E3. For example,
the fourth electrode E4 is set at the high potential VH. The third
electrode E3 is set at the low potential VL. In the example of FIG.
8B, the fourth current I4 flows from the third electrode E3 toward
the fourth electrode E4. For example, the fourth electrode E4 is
set at the low potential VL. The third electrode E3 is set at the
high potential VH. In these operations, the potentials of the first
electrode E1 and the second electrode E2 are arbitrary. For
example, the first electrode E1 may be set at a floating potential
VF1. For example, the second electrode E2 may be set at a floating
potential VF2.
[0110] In the example of FIG. 9A, the fourth current I4 flows from
the fourth electrode E4 toward the conductive member 50. For
example, the fourth electrode E4 is set at the high potential VH.
The first electrode E1 and the second electrode E2 are set at the
low potential VL. In the example of FIG. 9B, the fourth current I4
flows from the conductive member 50 toward the fourth electrode E4.
For example, the fourth electrode E4 is set at the low potential
VL. The first electrode E1 and the second electrode E2 are set at
the high potential VH. In these operations, the potential of the
third electrode E3 is arbitrary. For example, the third electrode
E3 may be set at the floating potential VF3.
[0111] For example, the third extending portion 13 has a region
opposing the second magnetic member 20. An electrical resistance
between the region and the second magnetic member 20 changes
depending on the orientation of the magnetization of the region
domain. For example, the information about the magnetization of the
third extending portion 13 can be acquired by detecting the signal
(at least one of current or voltage) according to the electrical
resistance. The controller 70 outputs a plurality of signals
corresponding to the electrical resistance. The plurality of
signals correspond to the magnetization (information) in the third
extending portion 13.
[0112] For example, the controller 70 outputs either a first signal
or a second signal in the reading operation RO. The first signal is
outputted after performing the first writing operation WO1. The
second signal is outputted after performing the second writing
operation WO2. The first signal differs from the second signal.
[0113] In embodiment, the conductive member 50 includes a metal.
The metal includes at least one selected from the group consisting
of tantalum and tungsten, for example. In such metals, a spin Hall
angle is negative, for example. In such metals, the absolute value
of the spin Hall angle is relatively large.
[0114] The metal included in the conductive member 50 may also
includes at least one selected from the group consisting of
platinum and gold, for example. In such metals, the spin Hall angle
is positive, for example. In such metals, the absolute value of the
spin Hall angle is relatively large.
[0115] A thickness of the conductive member 50 is not less than 0.5
nanometers and not more than 20 nanometers, for example.
[0116] In the embodiment, the first magnetic member 10 includes at
least one selected from the group consisting of Iron (Fe), Cobalt
(Co), and Nickel (Ni), for example. A thickness of the first
extending portion 11 of the first magnetic member 10 is not less
than 0.3 nanometers and not more than 20 nanometers. A thickness of
the second extending portion 12 is not less than 0.3 nanometers and
not more than 20 nanometers. Such thicknesses are lengths along the
fifth direction D5. A thickness of the third extending portion 13
is not less than 0.3 nanometers and not more than 20 nanometers.
This thickness is a length along a direction perpendicular to the
third direction D3.
[0117] The second magnetic member 20 includes at least one selected
from the group consisting of Iron (Fe), Cobalt (Co), and Nickel
(Ni), for example. A thickness of the second magnetic member 20 is
not less than 0.5 nanometers and not more than 50 nanometers, for
example. This thickness is a length along a direction perpendicular
to the third direction D3.
[0118] FIG. 10 is a schematic sectional view illustrating another
magnetic memory device according to the first embodiment.
[0119] FIG. 10 is a sectional view corresponding to A1-A2 line in
FIG. 1A. As shown in FIG. 10, in other magnetic memory device 111
according to the first embodiment, the second magnetic member 20 is
located on the first magnetic member 10. In addition, the
conductive member 50 is also located on the first magnetic member
10. Except this, the configuration of the magnetic memory device
111 is the same as that of the magnetic memory device 110. The
stable writing can be performed also in the magnetic memory device
111. The stable operation becomes possible.
[0120] FIG. 11 is a schematic sectional view illustrating another
magnetic memory device according to the first embodiment.
[0121] FIG. 11 is a sectional view corresponding to A1-A2 line in
FIG. 1 (a).
[0122] As shown in FIG. 11, in other magnetic memory device 112
according to the first embodiment, a conductive layer 58 is further
provided. Except this, the configuration of the magnetic memory
device 112 is the same as that of the magnetic memory device
110.
[0123] The conductive layer 58 is provided along the third
extending portion 13. The conductive layer 58 is electrically
connected with the third extending portion 13. Between the
conductive layer 58 and the second magnetic member 20, a part of
third extending portion 13 is located. By the conductive layer 58,
an electrical resistance of the third extending portion 13 can be
reduced. For example, a noise is suppressed. The stable operation
is obtained. The stable writing can be performed also in the
magnetic memory device 112.
[0124] FIG. 12 is a schematic plan view illustrating another
magnetic memory device according to the first embodiment.
[0125] FIG. 12 is a plan view corresponding to FIG. 1A.
[0126] As shown in FIG. 12, as other magnetic memory device 113
according to the first embodiment, the first side 51 may overlap
the third extending portion 13 in the fifth direction D5. Except
this, the configuration of the magnetic memory device 113 is the
same as that of the magnetic memory device 110. The stable writing
can be performed also in the magnetic memory device 113. The stable
operation becomes possible.
[0127] FIG. 13 is a schematic plan view illustrating another
magnetic memory device according to the first embodiment.
[0128] FIG. 13 is a plan view corresponding to FIG. 1A.
[0129] As shown in FIG. 13, an intermediate electrode E5 is
provided in another magnetic memory device 114 according to a first
embodiment. Except this, the configuration of the magnetic memory
device 114 is the same as that of the magnetic memory device
110.
[0130] As already described, the conductive member 50 includes the
first end portion 50a and the second end portion 50b. The
overlapping portion 55 is located between the first end portion 50a
and the second end portion 50b. A direction from the second end
portion 50b toward the first end portion 50a is along the fourth
direction D4. The overlapping portion 55 includes the first
overlapping region 55a and the second overlapping region 55b. The
first overlapping region 55a overlaps at least a part of the first
extending portion 11 in the fifth direction D5. The second
overlapping region 55b overlaps at least a part of the second
extending portion 12 in the fifth direction D5. The conductive
member 50 further includes an intermediate region 50c. The
intermediate region 50c is located between the first overlapping
region 55a and the second overlapping region 55b in the fourth
direction D4.
[0131] The controller 70 is electrically connected with the first
end portion 50a, the second end portion 50b, and the intermediate
region 50c. The intermediate electrode E5 is electrically connected
with the intermediate region 50c. The controller 70 is electrically
connected with the first electrode E1, the second electrode E2, and
the intermediate electrode E5.
[0132] In the magnetic memory device 114, by using the intermediate
electrode E5, a writing operation with more stability can be
performed.
[0133] FIG. 14A and FIG. 14B are schematic views illustrating
operations in other magnetic memory device according to a first
embodiment.
[0134] FIG. 14A corresponds to the first writing operation WO1.
FIG. 14B corresponds to the second writing operation WO2.
[0135] As shown in FIG. 14A, the controller 70 supplies the first
current I1 to the conductive member 50 in the first writing
operation WO1. As shown in FIG. 14B, the controller 70 supplies the
second current I2 to the conductive member 50 in the second writing
operation WO2.
[0136] For example, in the first writing operation WO1, the
controller 70 sets the first electrode E1 at the high potential VH.
The controller 70 sets the second electrode E2 at the low potential
VL. The controller 70 sets the intermediate electrode E5 at an
intermediate potential VM. The high potential VH is higher than the
intermediate potential VM. The intermediate potential VM is higher
than the low potential VL.
[0137] On the other hand, in the second writing operation WO2, the
controller 70 sets the first electrode E1 at the low potential VL.
The controller 70 sets the second electrode E2 at the high
potential VH. The controller 70 sets the intermediate electrode E5
at the intermediate potential VM.
[0138] Thus, the controller 70 makes the first potential of the
first end portion 50a higher than the third potential of the
intermediate region 50c in the first writing operation WO1. The
controller 70 makes the second potential of the second end portion
50b lower than the third potential in the first writing operation
WO1.
[0139] On the other hand, the controller 70 makes the first
potential lower than the third potential in the second writing
operation WO2. The controller 70 makes the second potential higher
than the third potential in the second writing operation WO2.
[0140] Thereby, the orientation of the current in the first
overlapping region 55a is stabilized, for example. For example, the
orientation of the current in the second overlapping region 55b is
stabilized. Thereby, the magnetic action to the first extending
portion 11 from the conductive member 50 is stabilized, for
example. For example, the magnetic action to the second extending
portion 12 from the conductive member 50 is stabilized. For
example, a stable writing can be performed.
[0141] The first state formed in the third extending portion 13 in
the first writing operation WO1 differs from the second state
formed in the third extending portion 13 in the second writing
operation WO2 in this case too. The different states are the states
of magnetization, for example. The different states correspond to
memory information. A stable writing can be performed also in the
magnetic memory device 114. The stable operation becomes
possible.
[0142] Hereinafter, examples of the shift operation in the magnetic
memory device 114 are described.
[0143] FIG. 15A and FIG. 15B are schematic views illustrating other
operations in the other magnetic memory device according to the
first embodiment.
[0144] These Figures illustrate two shift operations.
[0145] As shown in FIG. 15A, in an example of the shift operation,
the third current I3 flows from the conductive member 50 toward the
third end portion 13E.
[0146] As shown in FIG. 15B, in another example of the shift
operation, the third current I3 flows from the third end portion
13E toward the conductive member 50.
[0147] In the example of FIG. 15A, the first electrode E1, the
second electrode E2, and the intermediate electrode E5 are set at
the high potential VH. The third electrode E3 is set at the low
potential VL. In the example of FIG. 15B, the first electrode E1,
the second electrode E2, and the intermediate electrode E5 are set
at the low potential VL. The third electrode E3 is set at the high
potential VH.
[0148] Hereinafter, examples of the reading operation are
described.
[0149] FIG. 16A, FIG. 16B, FIG. 17A, and FIG. 17B are schematic
views illustrating other operations in the other magnetic memory
device according to the first embodiment.
[0150] In the example of FIG. 16A, the fourth electrode E4 is set
at the high potential VH. The third electrode E3 is set at the low
potential VL. In the example of FIG. 16B, the fourth electrode E4
is set at the low potential VL. The third electrode E3 is set at
the high potential VH.
[0151] In the example of FIG. 17A, the fourth electrode E4 is set
at the high potential VH. The intermediate electrode E5 is set at
the low potential VL. In the example of FIG. 17B, the fourth
electrode E4 is set at the low potential VL. The intermediate
electrode E5 is set at the high potential VH.
[0152] Also in this case, the electrical resistance between the
third extending portion 13 and the second magnetic member 20
changes depending on the orientation of the magnetization of the
third extending portion 13, for example. For example, a signal (at
least one of current and voltage) according to the electrical
resistance is detected. The controller 70 outputs a plurality of
signals (a first signal or a second signal) corresponding to the
electrical resistance. The plurality of signals correspond to the
magnetization (information) in the third extending portion 13.
Second Embodiment
[0153] FIG. 18 is a schematic perspective view illustrating a
magnetic memory device according to a second embodiment.
[0154] As shown in FIG. 18, a magnetic memory device 120 according
to the second embodiment also includes the first magnetic member
10, the conductive member 50, and the second magnetic member 20. In
this example, the magnetic memory device 120 further includes the
controller 70. In the magnetic memory device 120, the third
extending portion 13 has a tubular configuration extending along
the third direction D3. Further, a substrate 50s is provided. The
substrate 50s has a face 50f (for example, upper surface). The
conductive member 50 is provided on the face 50f. The at least a
part of the first extending portion 11 and the at least a part of
the second extending portion 12 are provided on the conductive
member 50. The third extending portion 13 is provided on at least a
part of the at least a part of the first extending portion 11, and
on at least a part of the at least a part of the second extending
portion 12. In this example, the third direction D3 is along the
fifth direction D5. The third direction D3 is substantially
perpendicular to the face 50f, for example. An angle between the
third direction D3 and the face 50f is not less than 85 degrees and
not more than 95 degrees, for example. Thus, the third extending
portion 13 extends along a direction perpendicular to the substrate
50s. Except this, the configuration of the magnetic memory device
120 is the same as that of the magnetic memory device 110.
[0155] Also in the magnetic memory device 120, the operation
described about the magnetic memory device 110 is performed.
[0156] The stable writing can be performed also in the magnetic
memory device 120. The stable operation becomes possible.
[0157] The embodiments may include the following configuration (for
example, "technical idea").
(Configuration 1)
[0158] A magnetic memory device, including:
[0159] a first magnetic member including a first extending portion,
a second extending portion, and a third extending portion, the
first extending portion extending along a first direction, the
second extending portion extending along a second direction
different from the first direction, the third extending portion
including a third connection portion connected with the first
extending portion and the second extending portion, the third
extending portion extending along a third direction;
[0160] a conductive member extending along a fourth direction, the
first direction being inclined with respect to the fourth
direction, the second direction being inclined with respect to the
fourth direction, the conductive member including an overlapping
portion, the overlapping portion overlapping at least a part of the
first extending portion and at least a part of the second extending
portion in a fifth direction, the fifth direction crossing the
first direction, the second direction and the fourth direction, the
conductive member including a metal; and
[0161] a second magnetic member, a direction from the third
extending portion toward the second magnetic member crossing the
third direction.
(Configuration 2)
[0162] The magnetic memory device according to configuration 1,
wherein
[0163] the conductive member has a first side extending along the
fourth direction and a second side extending along the fourth
direction,
[0164] a position of the first side in a sixth direction is located
between a position of the third extending portion in the sixth
direction and a position of the second side in the sixth
direction,
[0165] the sixth direction crosses the first direction, the second
direction and the fourth direction, and
[0166] the sixth direction is substantially perpendicular to the
fifth direction.
(Configuration 3)
[0167] The magnetic memory device according to configuration 2,
wherein
[0168] the first extending portion includes a first connection
portion and a first end,
[0169] the second extending portion includes a second connection
portion and a second end,
[0170] the first connection portion is connected with the third
connection portion,
[0171] the second connection portion is connected with the third
connection portion,
[0172] the first connection portion is positioned between the third
connection portion and the first end,
[0173] the second connection portion is positioned between the
third connection portion and the second end,
[0174] a position of the first end in the sixth direction is
between the position of the first side in the sixth direction and
the position of the second side in the sixth direction, and
[0175] a position of the second end in the sixth direction is
between the position of the first side in the sixth direction and
the position of the second side in the sixth direction.
(Configuration 4)
[0176] The magnetic memory device according to one of
configurations 1 to 3, wherein
[0177] a difference between a first angle and a second angle is not
more than 10 degrees,
[0178] the first angle is between the first direction and the
fourth direction, and
[0179] the second angle is between the second direction and a
reverse direction of the fourth direction.
(Configuration 5)
[0180] The magnetic memory device according to one of
configurations 1 to 3, wherein
[0181] a first angle between the first direction and the fourth
direction is not less than 10 degrees and not more than 80 degrees,
and
[0182] a second angle between the second direction and a reverse
direction of the fourth direction is not less than 10 degrees and
not more than 80 degrees.
(Configuration 6)
[0183] The magnetic memory device according to one of
configurations 1 to 5, wherein
[0184] a difference between a third angle and a fourth angle is not
more than 10 degrees,
[0185] the third angle is between the first direction and the third
direction, and
[0186] the fourth angle is between the second direction and the
third direction.
(Configuration 7)
[0187] The magnetic memory device according to one of
configurations 1 to 6, further comprising: a controller,
[0188] the conductive member including a first end portion and a
second end portion, the overlapping portion being provided between
the first end portion and the second end portion, a direction from
the second end portion toward the first end portion is along the
fourth direction,
[0189] the controller being electrically connected with the first
end portion and the second end portion,
[0190] the controller being configured to provide a first current
to the conductive member in a first writing operation and to
provide a second current to the conductive member in a second
writing operation,
[0191] a direction of the first current being from the first end
portion toward the second end portion,
[0192] a direction of the second current being from the second end
portion toward the first end portion,
[0193] a first state formed in the third extending portion in the
first writing operation is different from a second state formed in
the third extending portion in the second writing operation.
(Configuration 8)
[0194] The magnetic memory device according to one of
configurations 1 to 6, further comprising a controller,
[0195] the conductive member including a first end portion and a
second end portion, the overlapping portion being provided between
the first end portion and the second end portion, a direction from
the first end portion toward the second end portion is along the
fourth direction,
[0196] the overlapping portion including: [0197] a first
overlapping region overlapping the at least the part of the first
extending portion in the fifth direction; and [0198] a second
overlapping region overlapping the at least the part of the second
extending portion in the fifth direction,
[0199] the conductive member including an intermediate region
located between the first overlapping region and the second
overlapping region, the controller being electrically connected
with the first end portion, the second end portion and the
intermediate region,
[0200] the controller being configured to make a first electric
potential of the first end portion higher than a third electric
potential of the intermediate region in a first writing operation
and to make a second electric potential of the second end portion
lower than the third electric potential in the first writing
operation, to make the first electric potential lower than the
third electric potential in a second writing operation and to make
the second electric potential higher than the third electric
potential in the second writing operation,
[0201] a first state formed in the third extending portion in the
first writing operation being different from a second state formed
in the third extending portion in the second writing operation.
(Configuration 9)
[0202] The magnetic memory device according to one of
configurations 7 and 8, wherein
[0203] the third extending portion further includes a third end
portion,
[0204] the third connection portion is positioned between the first
connection portion and the third end portion,
[0205] the controller is further electrically connected with the
third end portion,
[0206] the controller is configured to supply a third current
flowing between the third end portion and the conductive member in
a shift operation.
(Configuration 10)
[0207] The magnetic memory device according to one of
configurations 7 to 9, wherein
[0208] the controller is further electrically connected with the
second magnetic member,
[0209] the controller is configured to output either one of a first
signal and a second signal in a reading operation,
[0210] the first signal is outputted after the first writing
operation is performed,
[0211] the second signal is outputted after the second writing
operation is performed, and
[0212] the first signal is different from the second signal.
(Configuration 11)
[0213] The magnetic memory device according to one of
configurations 1 to 10, wherein
[0214] the overlapping portion physically contacts the at least the
part of the first extending portion and the at least the part of
the second extending portion.
(Configuration 12)
[0215] The magnetic memory device according to one of
configurations 1 to 11, wherein the metal includes at least one
selected from the group consisting of Tantalum and Tungsten.
(Configuration 13)
[0216] The magnetic memory device according to one of
configurations 1 to 11, wherein the metal includes at least one
selected from the group consisting of Platinum and Gold.
(Configuration 14)
[0217] The magnetic memory device according to one of
configurations 1 to 13, wherein the third direction is along the
fifth direction.
(Configuration 15)
[0218] The magnetic memory device according to one of
configurations 1 to 14, wherein the third extending portion has a
pipe configuration extending along the third direction.
(Configuration 16)
[0219] The magnetic memory device according to one of
configurations 1 to 15, further comprising: a substrate having a
face,
[0220] the conductive member being provided on the face,
[0221] the at least the part of the first extending portion and the
at least the part of the second extending portion being provided on
the conductive member,
[0222] the third extending portion being provided on a part of the
at least the part of the first extending portion and a part of the
at least the part of the second extending portion, and
[0223] the third direction being substantially perpendicular to the
face.
(Configuration 17)
[0224] The magnetic memory device according to one of
configurations 1 to 16, further comprising: an intermediate member
being provided between the second magnetic member and the third
extending portion.
(Configuration 18)
[0225] The magnetic memory device according to configuration 17,
wherein the intermediate member includes a magnesium oxide.
(Configuration 19)
[0226] The magnetic memory device according to one of
configurations 1 to 18, wherein the first magnetic member includes
at least one selected form the group consisting of Iron, Cobalt,
and Nickel.
[0227] According to embodiment, the magnetic memory device in which
the stable operation is possible can be provided.
[0228] In the specification of the application, "a state of
electrically connected" includes a state where a plurality of
electric conductors contact physically with each other and a
current flows between the plurality of electric conductors. "A
state of electrically connected" includes a state where another
electric conductor is inserted between the plurality of electric
conductors and a current flows between the plurality electric
conductors. "A state of electrically connected" includes a state
where an electric element (switch element, such as a transistor
etc.) is inserted between the plurality of electric conductors and
a state where the current flows between the plurality of electric
conductors can be formed.
[0229] In the specification of the application, "perpendicular" and
"parallel" refer to not only strictly perpendicular and strictly
parallel but also include, for example, the fluctuation due to
manufacturing processes, etc. It is sufficient to be substantially
perpendicular and parallel.
[0230] Hereinabove, exemplary embodiments of the invention are
described with reference to specific examples. However, the
embodiments of the invention are not limited to these specific
examples. For example, one skilled in the art may similarly
practice the invention by appropriately selecting specific
configurations of components included in magnetic memory devices
such as magnetic member, conductive members, intermediate members,
and controllers, etc., from known art. Such practice is included in
the scope of the invention to the extent that similar effects
thereto are obtained.
[0231] Further, any two or more components of the specific examples
may be combined within the extent of technical feasibility and are
included in the scope of the invention to the extent that the
purport of the invention is included.
[0232] Moreover, all magnetic memory devices practicable by an
appropriate design modification by one skilled in the art based on
the magnetic memory devices described above as embodiments of the
invention also are within the scope of the invention to the extent
that the spirit of the invention is included.
[0233] Various other variations and modifications can be conceived
by those skilled in the art within the spirit of the invention, and
it is understood that such variations and modifications are also
encompassed within the scope of the invention.
[0234] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
invention.
* * * * *