JP5163638B2 - Magnetic body device and magnetic storage device - Google Patents

Description

  The present invention relates to a magnetic device and a magnetic memory device, and more particularly to a magnetic device capable of suppressing a leakage magnetic field from an end when no current is applied by using a magnetic field generated by passing a current through a conductor. The present invention relates to a magnetic storage device. This application is based on Japanese patent application No. 2007-057840 filed on March 7, 2007, claiming the benefit of priority from that application, the disclosure of that application should be cited Is incorporated here as it is.

  As a magnetic device, for example, a magnetic storage device in which a magnetoresistive element is used as a storage element and a memory is configured is known.

  As an example of the magnetoresistive element, a TMR (Tunneling Magnetoresistance) structure in which a tunnel insulating film is sandwiched between two magnetic bodies will be described. FIG. 1 is a diagram of Roy Scheuerlein, et al. , “A 10 ns Read and Write Non-Volatile Memory Array Usage a Magnetic Tunnel Junction and FET Switch in Search Cell ED. FIG. The TMR element includes an antiferromagnetic layer 201, a pinned layer 202, a tunnel insulating layer 203, and a ferromagnetic free layer 204 that are stacked. The antiferromagnetic material layer 201 is made of FeMn (10 nm). The ferromagnetic pinned layer 202 is made of CoFe (2.4 nm). The tunnel insulating layer 203 is made of Al2O3. The ferromagnetic free layer 204 is made of NiFe (5 nm). Conductor wiring is connected to the antiferromagnetic material layer 201 and the free layer 204 so that a voltage can be applied. The magnetization direction of the pinned layer 202 is fixed in a certain direction by the antiferromagnetic material layer 201. The free layer 204 is formed so as to be easily magnetized in a certain direction, and the magnetization direction can be changed by applying a magnetic field from the outside. Of the horizontal directions of the free layer 204, the direction that is easy to magnetize is called the easy axis, and the direction that is perpendicular to the easy axis and difficult to magnetize is called the hard axis. When a voltage is applied between the free layer 204 and the pinned layer 202, a current flows through the tunnel insulating film 203, but the resistance value changes depending on the relationship between the magnetization directions of the free layer 204 and the pinned layer 202. That is, the resistance is low when the magnetization directions are the same, and the resistance is high when the magnetization directions are opposite.

  Next, a non-volatile memory (magnetic storage device) using a TMR element as a storage element will be described. FIG. Durlam, et al. , “Nonvolatile RAM based on Magnetic Tunnel Junction Elements”, 2000 IEEE International Solid-State Circuits Conferencing DIGEST OF TECHNICAL PAPERS, which is an example of a non-volatile figure of 130. In the nonvolatile memory 210, a pair of intersecting wires are installed above and below the TMR elements 205 arranged in an array. The upper wiring 206 is connected to the free layer of the TMR element 205. The antiferromagnetic material layer of the TMR element 205 is connected to the drain of the transistor 208 formed in the lower layer via the third wiring 207. A synthetic magnetic field is generated in the vicinity of the intersection by flowing current through the two wirings B (any one of B1 to B4) and the wiring D (any one of D1 to D4), and the magnetization direction of the free layer is set according to the direction of the current. . Thereby, the resistance value of the TMR element 205 can be changed. Data reading is performed as follows. First, the transistor 208 connected to the TMR element 205 to be read is turned on by the wiring W. Next, a voltage is applied from the wiring B to the TMR 205 element. Thereby, a current flows through the TMR element 205. Reading is performed by evaluating the resistance value of the TMR element 205 with the flowing current.

  In these wirings B and D, there is a method in which a magnetic film such as NiFe is formed on three surfaces other than the surface on which the TMR element 205 is present to strengthen the magnetic field generated on the TMR element 205 side. May be used. In this way, the magnetic field generated when a current is passed through the wirings B and D concentrates through the magnetic film having a high magnetic permeability. Therefore, a magnetic field is concentrated from the end on the TMR element 205 side, and the magnetic field applied to the TMR element 205 can be strengthened. The magnetic body (film) formed on the wiring in this way is hereinafter referred to as YOKE.

  In the above-described wiring with YOKE, the magnetic film has a long shape in the wiring extending direction. Therefore, an easy axis is formed in the extending direction due to the shape anisotropy. In this case, YOKE is magnetized in any direction parallel to the easy axis at the time of film formation and processing. At this time, in one wiring, the entire YOKE may be magnetized in the same direction. However, there is a possibility that a certain region is magnetized in one direction and a region adjacent thereto is magnetized in the opposite direction to form a magnetic domain. In this case, a magnetic field is generated because the magnetization directions are reversed in the magnetic domain portions. If there is a TMR element in the vicinity of the magnetic domain, the magnetic field affects the characteristics of the TMR element. Therefore, this causes a variation in characteristics between TMR elements.

  Further, by applying an external magnetic field having a magnetic field component in the wiring extending direction after YOKE formation, the entire YOKE can be uniformly magnetized in the direction of the easy axis close to the external magnetic field direction. In this case, there is no magnetic domain in the middle of the wiring, so no magnetic field is generated in the middle. However, the magnetic material is interrupted at both ends of the wiring, and a magnetic field is generated. For this reason, the characteristics of the TMR elements in the vicinity of the end of the wiring and the TMR elements in the part away from the end are different, and there is a problem in that the characteristics between the TMR elements vary.

  As a related technique, Japanese Patent Laid-Open No. 2003-209226 (US 6717845) discloses a magnetic memory. The magnetic memory includes a magnetoresistive element having a magnetic recording layer and a first wiring extending in a first direction above or below the magnetoresistive element. Information is recorded on the magnetic recording layer by a magnetic field formed by passing a current through the first wiring. The first wiring has a coating layer made of a magnetic material on at least one of both side surfaces thereof. The coating layer has uniaxial anisotropy that facilitates magnetization along the longitudinal direction of the first wiring.

    Japanese Patent Application Laid-Open No. 2004-128011 (US67665821) discloses a magnetic memory. This magnetic memory includes a first wiring, a second wiring, a magnetoresistive effect element, and a yoke. The second wiring intersects with the first wiring. The magnetoresistive element has a memory layer that is provided in an intersecting region of the first and second wirings, and whose magnetization direction changes according to a current magnetic field generated by flowing a current through the first and second wirings. The yoke has at least two soft magnetic layers stacked via a nonmagnetic layer and magnetically coupled to at least one of the first and second wirings.

  Japanese Patent Application Laid-Open No. 2005-64211 discloses a magnetic storage device and a manufacturing method thereof. The magnetic memory device includes a first wiring, a second wiring, and a magnetoresistive storage element. The second wiring three-dimensionally intersects with the first wiring. The magnetoresistive storage element is electrically connected to the second wiring at an intersection region between the first wiring and the second wiring. Furthermore, a first magnetic layer and a second magnetic layer are provided. The first magnetic layer is composed of a high magnetic permeability layer formed on both sides of the first wiring and on the surface opposite to the surface facing the memory element. The second magnetic layer is composed of a high permeability layer formed on both sides of the second wiring and on the surface opposite to the surface facing the memory element. The first magnetic layer and the second magnetic layer are made of different high permeability materials.

  An object of the present invention is to provide a magnetic device and a magnetic memory device in which the generation of a magnetic field is suppressed in the middle of wiring having YOKE and at the end of the wiring.

  These objects and other objects and benefits of the present invention can be easily confirmed by the following description and the accompanying drawings.

  The magnetic device according to the present invention includes a magnetic layered film provided along the wiring facing at least one surface of the conductive wiring that is long in one direction, and a magnetic field induced by a current flowing through the wiring. And a functional body that embodies the function by interaction with. The magnetic layered film includes a plurality of magnetic layers and at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers. The nonmagnetic conductor layer ferromagnetically couples or antiferromagnetically couples the magnetic layers on both sides. At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides. The total amount of magnetization of the plurality of magnetic layers is substantially zero. Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction Is different.

  The magnetic storage device of the present invention includes a plurality of first wirings extending in a first direction, a plurality of second wirings extending in a second direction, the plurality of first wirings, and the plurality of second wirings. And a plurality of magnetic devices each having one end connected to the corresponding first wiring. Each of the plurality of magnetic devices is induced by a magnetic layered film provided along the first wiring, facing at least one surface of the first wiring, and a current flowing through the first wiring. And a magnetic device that stores information by interaction with a magnetic field. The magnetic layered film includes a plurality of magnetic layers and at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers. The nonmagnetic conductor layer causes the magnetic layers on both sides to be ferromagnetically coupled or antiferromagnetically coupled. At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides. The total amount of magnetization of the plurality of magnetic layers is substantially zero. Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction Is different.

  The magnetic storage device of the present invention includes a plurality of first wirings extending in a first direction, a plurality of second wirings extending in a second direction, the plurality of first wirings, and the plurality of second wirings. And a plurality of magnetic devices each having one end connected to the corresponding second wiring. Each of the plurality of magnetic body devices faces at least one surface of the internal wiring connected to the first wiring and flows through the magnetic multilayer film provided along the internal wiring and the internal wiring A magnetic device that stores information by interaction with a magnetic field induced by current. The magnetic layered film includes a plurality of magnetic layers and at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers. The nonmagnetic conductor layer causes the magnetic layers on both sides to be ferromagnetically coupled or antiferromagnetically coupled. At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides. The total amount of magnetization of the plurality of magnetic layers is substantially zero. Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction Is different.

FIG. 1 is a cross-sectional view showing an example of a TMR element in the related art. FIG. 2 is a perspective view showing an example of a nonvolatile memory in the related art. FIG. 3 is a cross-sectional view of the main part showing the configuration of the embodiment of the magnetic device of the present invention. FIG. 4 is a principal plan view showing the configuration of the embodiment of the magnetic device of the present invention. FIG. 5 is a schematic circuit block diagram showing the configuration of the first and second embodiments of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 6 is a cross-sectional view of the principal part showing the configuration of the first embodiment of the memory cell as the magnetic device of the present invention. FIG. 7 is a plan view of the main part of the memory array of the first and second embodiments of the magnetic storage device to which the magnetic device of the present invention is applied. FIG. 8 is a fragmentary cross-sectional view showing the configuration of the first embodiment of the memory cell as the magnetic device of the present invention. FIG. 9 is a schematic circuit block diagram showing the configuration of the third embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 10 is a fragmentary cross-sectional view showing the configuration of the third embodiment of the memory cell as the magnetic device of the present invention. FIG. 11 is a plan view of the main part of the memory array of the third embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 12 is a top view of the main part showing another configuration of the wiring and YOKE in the present invention. FIG. 13 is a cross-sectional view along AA ′ in FIG. 12. 14 is a cross-sectional view taken along the line BB ′ in FIG.

  Embodiments of a magnetic device and a magnetic storage device according to the present invention will be described below with reference to the accompanying drawings.

(First embodiment)
A first embodiment of a magnetic device and a magnetic storage device of the present invention will be described with reference to the accompanying drawings. FIG. 3 is a cross-sectional view of the main part showing the configuration of the magnetic device according to the first embodiment of the present invention. FIG. 4 is a principal plan view showing the configuration of the first embodiment of the magnetic device according to the present invention. In addition, the arrow in each layer in FIG. 3 has shown the direction of the magnetization in the layer. Hereinafter, the same applies to the sectional views of the magnetic device.

  As shown in FIG. 3, the magnetic body device 1 includes a functional body 4, a magnetic body laminated film 20, and a conductor wiring 5.

  The conductor wiring 5 is made of a conductive metal. A magnetic field is formed around the current caused by the current flowing inside. A predetermined function is realized using this magnetic field. The predetermined function is exhibited together with all or part of the magnetic laminated film 20. The function is exemplified by the function of changing the magnetization direction inside the functional body 4. The conductor wiring 5 is exemplified by a bit line or a word line through which a write current flows in a magnetic storage device (magnetic random access memory).

  The magnetic laminated film 20 is provided directly on at least a part of at least one surface of the conductor wiring 5 or with a nonmagnetic conductor or a nonmagnetic insulator interposed therebetween. A plurality of magnetic bodies 2 and antiferromagnetically coupled nonmagnetic conductors 3 may be provided, and a plurality of nonmagnetic conductors 11 may be included. The plurality of magnetic bodies 2 are a plurality of layered magnetic bodies 2-1 to 2-n (n ≧ 2, natural number). A magnetic body 2-n is provided on the side of the magnetic layered film 20 in contact with the conductor wiring 5.

  The plurality of nonmagnetic conductors 11 are a plurality of layered nonmagnetic conductors 11-1 to 11- (n-1). The jth (j = 1 to (n−1)) nonmagnetic conductor 11-j includes a jth magnetic body 2-j, a (j + 1) th magnetic body 2- (j + 1) th magnetic body 2- (J + 1). The nonmagnetic conductor 11-j causes the magnetic body 2-j and the magnetic body 2- (j + 1) in contact with both sides to be ferromagnetically coupled or antiferromagnetically coupled.

  The antiferromagnetically coupled nonmagnetic conductor 3 includes an i-th (i = 1 to (n−1)) magnetic body 2-i and (i + 1) between the magnetic body 2-1 and the magnetic body 2-n. And the second magnetic body 2- (i + 1). Instead, it is provided at the position of the i-th nonmagnetic conductor 11-i. That is, at least one of the nonmagnetic conductors 11 is an antiferromagnetic-coupled nonmagnetic conductor 3. The position of the antiferromagnetically coupled nonmagnetic conductor 3 is arbitrary. The antiferromagnetic-coupled nonmagnetic conductor 3 antiferromagnetically couples the magnetic body 2-i and the magnetic body 2- (i + 1) in contact with both sides.

  However, when n = 2, that is, when the magnetic body 2 has two layers (2-1, 2-2), there is no antiferromagnetic coupling between the magnetic body 2-1 and the magnetic body 2-2. The magnetic conductor 3 is preferentially provided. When n> 2, that is, when there are three or more magnetic layers 2, there are two or more between the magnetic layers 2, so that the antiferromagnetic coupling nonmagnetic conductor 3 is provided between the two. A nonmagnetic conductor 11 is provided between the other.

  That is, in the magnetic device 1, the magnetic body 2 (−1) is formed in contact with the functional body 4, and the nonmagnetic conductor 11 and the magnetic body 2 are alternately formed. The number of repetitions is 1 or more (n ≧ 2). In contact with the last magnetic body 2-n, a functional body 5 that implements a desired function together with the magnetic body 2 is formed.

  The magnetization directions of the magnetic bodies 2-1 to 2-n are fixed before using the magnetic body device, and the change of the magnetization direction during the functional operation is less than 90 degrees and does not reverse in the reverse direction. Since the magnetic bodies 2 of the magnetic bodies 2-1 to 2-n are ferromagnetically coupled or antiferromagnetically coupled, the magnetization direction of the magnetic body 2-1 is opposite or the same as the magnetization direction of the magnetic body 2-n. Fixed in direction. Furthermore, among the magnetic bodies 2 included in the magnetic bodies 2-1 to 2 -n, the total amount of magnetization of the layers that are magnetized in the same direction as the magnetic body 2-1 is magnetized in the opposite direction to the magnetic body 2-1. It is almost equal to the total amount of magnetization of the layers to be performed. That is, the sum total of the magnetization amounts of the magnetic bodies 2-1 to 2-n is almost zero. Here, “substantially” means that the manufacturing error is completely equal or cannot be made zero, so that the manufacturing error is considered equal or zero. Furthermore, among the magnetic bodies 2 included in the magnetic bodies 2-1 to 2-n, the anisotropic magnetic field of the entire layer that is magnetized in the same direction as the magnetic body 2-1 is opposite to the magnetic body 2-1. Different from the anisotropic magnetic field of the entire magnetized layer.

  The functional body 4 is disposed in the vicinity of the conductor wiring 5 on the side where the magnetic bodies 2-1 to 2-n are not formed. The function body 4 realizes its function by a magnetic field induced (generated) by a current flowing through the conductor wiring 5. The magnetic layered film 20 assists its function. The functional body 4 is exemplified by an MTJ element of a memory cell in a magnetic storage device (magnetic random access memory). In that case, the MTJ element realizes a function of storing information by rotating its own magnetization direction by a magnetic field induced by a write current flowing in the conductor wiring 5.

  As shown in FIG. 4, the magnetic laminated film 20 is provided along the longitudinal direction of the conductor wiring 5. By forming the magnetic body 2 in such a shape, the magnetic body 2 has an easy axis (magnetization) indicating a direction axis that is easily magnetized due to the shape anisotropy. In this case, the easy axis is parallel to the longitudinal direction of the conductor wiring 5. Thereby, the magnetization of the magnetic body 2 is easily oriented in the easy axis direction. Therefore, the magnetization of the other magnetic body 2 laminated and ferromagnetically coupled or antiferromagnetically coupled to the magnetic body 2 is easily oriented in a direction parallel to the easy axis direction. As a result, the magnetization of the entire magnetic multilayer film 20 can be easily fixed in a direction parallel to the easy axis direction. It is preferable that the number of the magnetic bodies 2 here is large. This is because the magnetization direction can be easily fixed.

Next, the operation of the first embodiment of the magnetic device of the present invention (the operation method of the magnetic device) will be described.
The magnetic device 1 has a magnetic laminated film 20 that is long in one direction along the conductor wiring 5. Therefore, an easy axis (magnetization) indicating a direction axis that is easily magnetized is formed in the magnetic layered film 20 (magnetic body 2) due to shape anisotropy. The magnetic device 1 is subjected to a process of being exposed to a magnetic field having a component in the easy axis direction of the magnetic body 2-1 during manufacture or before use. The magnetization direction of the magnetic bodies 2-1 to 2-n approaches the applied magnetic field direction by the magnetic field applied in the process. At this time, among the magnetic bodies 2 included in the magnetic bodies 2-1 to 2 -n, the anisotropic magnetic field of the entire layer magnetized in the same direction as the magnetic body 2-1 is opposite to the magnetic body 2-1. Different from the anisotropic magnetic field of the entire magnetized layer. For this reason, the magnetization direction of the magnetic body group on the side having a larger anisotropic magnetic field settles on the side closer to the applied magnetic field direction in the easy axis direction. On the other hand, the magnetization direction of the magnetic body group on the side having a smaller anisotropic magnetic field is opposite to the settled direction. In this way, the magnetization direction of the magnetic body 2 can be set to a desired direction.

  When no current is passed through the conductor wiring 5, the magnetization direction of the magnetic body 2 is one of the easy axis directions. At this time, since the total amount of magnetization in each direction is equal, the magnetic field of the magnetic body 2 is canceled out at the end of the conductor wiring 5, and no leakage magnetic field is generated. Further, since the magnetization direction is uniformly directed to each magnetic body 2, no magnetic domain is formed in the magnetic body 2 at a position in the middle of the conductor wiring 5, and no magnetic field is generated. However, since the magnetic body 2 is interrupted at the end portion of the conductor wiring 5, a magnetic domain may be generated. However, even here, the magnetic field is canceled and no leakage magnetic field is generated.

  When a current is passed through the conductor wiring 5, the magnetization direction of all the magnetic bodies 2 is inclined in the direction of the magnetic field induced by the current, and a magnetic field is generated from the side surface of the magnetic body 2. The magnetic field is applied to the functional body 4 to realize a desired function. In the magnetic device 1, the magnetic field applied to the functional body 4 increases when the magnetic bodies 2-1 to 2-n are not formed.

  In the embodiment of the present invention, the minimum configuration of the magnetic laminated film 20 is the magnetic body 2-1, the antiferromagnetic coupling conductor 3, and the magnetic body 2-2. Further, the magnetic material used may be different for each magnetic body 2, or each magnetic body 2 may have a laminated structure of a plurality of magnetic materials. FIG. 3 shows an example in which the magnetic laminated film 20 is formed on the surface of the conductor wiring 5 opposite to the functional body 4. However, the magnetic layered film 20 may be formed on the same side of the conductor wiring 5 as the functional body 4.

Next, the first embodiment of the magnetic device and the magnetic storage device of the present invention will be described in detail.
FIG. 5 is a schematic circuit block diagram showing the configuration of the first embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 6 is a cross-sectional view of the principal part showing the configuration of the first embodiment of the memory cell as the magnetic device of the present invention. FIG. 7 is a plan view of the main part of the memory array of the first embodiment of the magnetic memory device to which the magnetic device of the present invention is applied.

  First, the circuit configuration will be described with reference to FIG. The magnetic storage device 30 is a magnetic random access memory. The magnetic storage device 30 includes a plurality of word lines 50, a plurality of bit lines 51a, a plurality of bit lines 51b, a plurality of memory cells 52, a read control circuit 54, a word line control circuit 55, a word line termination circuit 56, and a bit line control. A circuit 57, a bit line termination circuit 58, and a sense amplifier 59 are provided.

  The plurality of word lines 50 extend in the X direction (first direction). The word line 50 has one end connected to the word line control circuit 55 and the other end connected to the word line termination circuit 56. The plurality of bit lines 51a extend in the Y direction (second direction orthogonal to the first direction). The bit line 51 a has one end connected to the bit line control circuit 57 and the other end connected to the bit line termination circuit 58. The plurality of bit lines 51b extend in the Y direction (second direction orthogonal to the first direction). The bit line 51 b has one end connected to the gate of the selection transistor 61 of the memory cell 52 and the other end connected to the read control circuit 54. The bit line 51b is shared by the memory cells 52 (select transistor 61) arranged along the extending direction (Y direction).

  The plurality of memory cells 52 are provided corresponding to the intersections of the plurality of word lines 50 and the plurality of bit lines 51a. The memory cell 52 includes a magnetoresistive storage element 60 and a selection transistor 61. Here, the magnetoresistive memory element 60 is a giant magnetoresistive (GMR) element. The magnetoresistive memory element 60 has two terminals. One terminal is connected to the word line 50 and the other terminal is connected to the source of the selection transistor 61. The drain of the selection transistor 61 is grounded, and the gate is connected to the read control circuit 54 via the bit line 51b.

  The read control circuit 54 selects the selected bit line 51b from the plurality of bit lines 51b during the read operation. The word line control circuit 55 selects the selected word line 50 from the plurality of word lines 50. The word line termination circuit 56 terminates the plurality of word lines 50 during a write operation. The bit line control circuit 57 selects the selected bit line 51a from the plurality of bit lines 51a during the write operation. The bit line termination circuit 58 terminates the plurality of bit lines 51a during the write operation. The sense amplifier 59 is connected to the word line control circuit 55, and performs data discrimination by comparing the word line potential acquired via the word line control circuit 55 with the reference potential Vref during a read operation.

Next, the configuration of the magnetoresistive storage element 60 of the memory cell 52 will be described with reference to FIG.
The magnetoresistive storage element 60 is a GMR element, a Ta film 72 as a lower electrode, a NiFe film 73 as a pinned layer, a PtMn film 74, a CoFe film 75, a Ru film 76 and a CoFe film 77, and a Cu film as a spacer layer. 78, a NiFe film 79 as a free layer, and a Ta film 80 as an upper electrode. Here, the lower structure of the magnetoresistive memory element 60 (NiFe film 73, PtMn film 74, CoFe film 75, Ru film 76, CoFe film 77, and Cu film 78) is also referred to as BASE86. The magnetoresistive storage element 60 corresponds to the functional body 4.

  The Ta film 72 as the lower electrode is connected to a semiconductor substrate (not shown) provided with a transistor including the selection transistor 61 and a wiring including a plurality of bit lines 51 a and 51 b through a W via 70. . The Ta film 80 as the upper electrode is connected to the AlCu wiring 85 as the word line 50 via the Cu via 84.

  Here, the AlCu wiring 85 corresponds to the conductor wiring 5. A Ta film 119, a NiFe film 120, a Ru film 121, a NiFe film 122, a Ta film 123, a NiFe film 124, and a Ta film 125 are stacked in order from the side closer to the AlCu wiring 85 on both side surfaces of the AlCu wiring 85. ing. Here, the NiFe film 120 corresponds to the magnetic body 2. The Ru film 121 corresponds to the antiferromagnetically coupled nonmagnetic conductor 3 (nonmagnetic conductor 11). The NiFe film 122 corresponds to the magnetic body 2. The Ta film 123 corresponds to the nonmagnetic conductor 11. The NiFe film 124 corresponds to the magnetic body 2.

Next, a method for manufacturing a memory cell will be described with reference to FIG.
First, a transistor including the selection transistor 61 and a wiring including a plurality of bit lines 51a and 51b are formed on a semiconductor substrate (not shown). Thereafter, a SiO ₂ film 71 as an interlayer insulating film is formed with a film thickness of 300 nm on the semiconductor substrate. A W via 70 is formed at a predetermined position of the SiO ₂ film 71. Next, a 20 nm thick Ta film 72, a 1 nm thick NiFe film 73, a 10 nm thick PtMn film 74, a 2 nm thick CoFe film 75, a 0.8 nm thick Ru film 76, and a 2 nm thick CoFe film. A film 77, a Cu film 78 having a thickness of 2.5 nm, a NiFe film 79 having a thickness of 4 nm, a Ta film 80 having a thickness of 30 nm, and a SiO ₂ film 81 having a thickness of 70 nm are formed by sputtering. Here, the Ru film 76 has such a thickness that the CoFe film 75 and the CoFe film 77 are antiferromagnetically coupled.

Subsequently, a resist is formed in the shape of GMR (magnetoresistance memory element 60) by photolithography technology, and the SiO ₂ film 81 other than the resist is processed by selective ion processing technology (RIE: Reactive Ion Etching). Remove by ashing. Next, the Ta film 80 and the NiFe film 79 are removed by milling using the SiO ₂ film 81 pattern as a mask. Then, after forming a SiN film 82 as a protective film on the entire surface, a resist is formed in a BASE 86 shape, and a SiN film 82, a Cu film 78, a CoFe film 77, a Ru film 76, a CoFe film 75, a PtMn film 74, and a NiFe film. 73 and Ta film 72 are processed.
The magnetoresistive memory element 60 can be formed by the above manufacturing process.

  As shown in FIG. 7, a Cu film 78 as a spacer layer, a CoFe film 77 / Ru film 76 / Ru film 76 / CoFe film 75 / PtMn film 74 / NiFe film 73 as a pinned layer, and a Ta film 72 as a lower electrode are formed. The included BASE 86 is a rectangle that is long in the extending direction (X direction) of the word line 50 (AlCu wiring 85). The NiFe film 79 as a free layer is formed on the BASE 86 and has an oval shape that is long in the extending direction (X direction) of the word line 50. However, in FIG. 7, the selection transistor 61 and the bit line 51b are not shown.

Thereafter, a SiO ₂ film 83 as an interlayer insulating film is formed on the entire surface by plasma CVD. Thereafter, the entire surface is flattened by a CMP (Chemical Mechanical Polishing) technique. Subsequently, via holes penetrating the SiO ₂ film 83, the SiN film 82, and the SiO ₂ film 81 on the free layer (NiFe film 79) are formed by a photolithography technique and a dry etching technique, and a Cu via 84 is formed. . Thereafter, a Ti film (30 nm), an AlCu film (500 nm), and a TiN film (30 nm) are stacked and processed by a photolithography technique and a dry etching technique to form an AlCu wiring 85 as the word line 50.

  Furthermore, a 10 nm thick Ta film 119, a 10 nm thick NiFe film 120, a 0.4 nm thick Ta film 121, a 10 nm thick NiFe film 122, a 0.8 nm thick Ru film 123, A 20 nm NiFe film 124 and a 10 nm thick Ta film 125 are formed by sputtering. Thereafter, the entire surface is processed by milling to form YOKE 20a only on both side surfaces of the AlCu wiring 85. At this time, the Ta film 121 has a thickness at which the NiFe film 120 and the NiFe film 122 are ferromagnetically coupled. The Ru film 123 has a thickness at which the NiFe film 122 and the NiFe film 124 are antiferromagnetically coupled. As a result, the NiFe film 120 and the NiFe film 122 are magnetized in the same direction, and the NiFe film 122 and the NiFe film 124 are magnetized in the opposite directions, respectively.

Next, a magnetic field of about 1000 to 10000 Oe is applied in the long side direction of the upper wiring (AlCu wiring 85) pattern. As a result, the three NiFe films 120, 122, and 124 of the YOKE 20a provided in contact with the AlCu wiring 85 are oriented in the direction along the magnetic field. When the magnetic field is returned to zero, since the NiFe films 120 and 122 and the NiFe film 124 are antiferromagnetically coupled, the magnetization direction tends to be reversed. Since the AlCu wiring 85 is a long rectangle in the extending direction, the YOKE 20a also has a long rectangular shape. Therefore, in YOKE 20a, an easy axis is formed in the extending direction due to shape anisotropy. The NiFe films 120 and 122 and the NiFe film 124 have the same amount of magnetization, but since the NiFe films 120 and 122 are divided into two, the anisotropic magnetic field is small. Therefore, the NiFe film 124 is stabilized toward the long side direction axis close to the applied magnetic field direction, and the NiFe films 120 and 122 are stabilized toward the opposite direction. Thereby, the magnetization direction of YOKE20a can be set to a desired direction.
Thus, a memory cell can be manufactured.

Next, an operation method of the memory cell will be described with reference to FIG. First, the writing method will be described.
The bit line control circuit 57 selects the selected bit line 51a from the plurality of bit lines 51a. The word line control circuit 55 selects the selected word line 50 from the plurality of word lines 50. By passing a current through the selected bit line 51a and the selected word line 50, a combined magnetic field can be applied to the magnetoresistive storage element 60 of the memory cell 52 (selected cell) at the position where the two intersect. The magnetization reversal current of the magnetoresistive storage element 60 varies depending on the magnitude of the magnetic field of the word line 50. Therefore, data is written to only one cell by setting the bit line 51a current so that inversion does not occur in a cell in which the word line 50 current does not flow, and inversion occurs in a cell in which the word line 50 current flows. Is possible. The magnetization direction can be set by the direction of the bit line 51a current. At this time, since the magnetic field is also applied to the pinned layer 20, the material, shape, and magnetic coupling strength of the pinned layer 20 are set so as not to be reversed by the write magnetic field.

Next, a reading method will be described.
The read control circuit 54 selects the selected bit line 51b from the plurality of bit lines 51b. Thereby, the selection transistor 61 of the memory cell 52 (selected cell) to be read is turned on. The word line control circuit 55 selects the selected word line 50 from the plurality of word lines 50. At that time, the word line termination circuit 56 is in an open state. When a voltage is applied to the selected word line 50 by the word line control circuit 55, a read current flows through the selected word line 50, the magnetoresistive storage element 60, the selection transistor 61, and the ground path. The magnitude of the read current varies depending on the resistance value (value of stored data) of the magnetoresistive storage element 60 of the memory cell 52 to be read. The word line control circuit 55 converts the current value of the read current into a voltage and outputs it to the sense amplifier 59 as the sense voltage Vs. To the sense amplifier 59, an intermediate value of voltages (V0 and V1) output by data values (“0” and “1”) is given as Vref. The sense amplifier 59 determines the data (either “0” or “1”) written in the memory cell 52 by comparing Vref and Vs.

  In the above embodiment, the bit line is described as the lower side (semiconductor substrate side) and the word line is described as the upper side. However, the present invention is not limited to this, and the positional relationship between the bit line and the word line may be reversed.

  According to the present embodiment, the magnetization direction of YOKE can be set in a desired direction, and the leakage magnetic field from the end of YOKE that causes variation in characteristics can be suppressed. As a result, variation in magnetic properties of YOKE is reduced, and a magnetic storage device with a good yield can be obtained.

(Second Embodiment)
A second embodiment of the magnetic device and magnetic storage device of the present invention will be described with reference to the accompanying drawings. The principal part sectional view and the principal part plan view showing the configuration of the second embodiment of the magnetic device shown in FIG. 3 and FIG. 4 are the same as those of the first embodiment, and the description thereof will be omitted.

Next, a second embodiment of the magnetic device and the magnetic storage device of the present invention will be specifically described.
FIG. 5 is a schematic circuit block diagram showing the configuration of the first embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 8 is a fragmentary cross-sectional view showing the configuration of the first embodiment of the memory cell as the magnetic device of the present invention. FIG. 7 is a plan view of the main part of the memory array of the first embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. 5 and FIG. 7 are the same as those in the first embodiment except for the memory cell 52a (the magnetoresistive storage element 60a, YOKE 20b, and BASE 86a), and thus description thereof is omitted.

Next, the configuration of the magnetoresistive storage element 60a of the memory cell 52a will be described with reference to FIG.
The magnetoresistive storage element 60a is a TMR element, and includes a Ta film 72, Ta film (not shown) as a lower electrode, a NiFe film 73, a PtMn film 74, a CoFe film 75, a Ru film 76, and a CoFe film as pin layers. 77, an MgO film 95 as a tunnel barrier layer, a NiFe film 79 as a free layer, and a Ta film 80 as an upper electrode. Here, the lower structure of the magnetoresistive memory element 64 (NiFe film 73, PtMn film 74, CoFe film 75, Ru film 76, CoFe film 77, and MgO film 95) is also referred to as BASE 86a. The magnetoresistive storage element 64 corresponds to the functional body 4.

  The Ta film 72 as the lower electrode is connected to a semiconductor substrate (not shown) provided with a transistor including the selection transistor 61 and a wiring including a plurality of bit lines 51 a and 51 b through a W via 70. . The Ta film 80 as the upper electrode is connected to the AlCu wiring 85 as the word line 50 via the Cu via 84.

  Here, the AlCu wiring 85 corresponds to the conductor wiring 5. The Ta film 119, the NiFe film 126, the Ru film 127, the CoFe film 128, and the side surface and the upper surface (three surfaces excluding the surface connected to the Cu via 84) of the AlCu wiring 85 are arranged in order from the side closer to the AlCu wiring 85. A Ta film 129 is stacked. Here, the NiFe film 126 corresponds to the magnetic body 2. The Ru film 127 corresponds to the antiferromagnetically coupled nonmagnetic conductor 3 (nonmagnetic conductor 11). The CoFe film 128 corresponds to the magnetic body 2.

Next, a method for manufacturing a memory cell will be described with reference to FIG.
First, a transistor including the selection transistor 61 and a wiring including a plurality of bit lines 51a and 51b are formed on a semiconductor substrate (not shown). Thereafter, a SiO ₂ film 71 as an interlayer insulating film is formed with a film thickness of 300 nm on the semiconductor substrate. A W via 70 is formed at a predetermined position of the SiO ₂ film 71. Next, a 20 nm thick Ta film 72, a 8 nm thick Ta film, a 1 nm thick NiFe film 73, a 10 nm thick PtMn film 74, a 2 nm thick CoFe film 75, and a 0.8 nm thick Ru film. 76, a 2 nm thick CoFe film 77, a 1.5 nm thick MgO film 95, a 4 nm thick NiFe film 79, a 30 nm thick Ta film 80, and a 70 nm thick SiO ₂ film 81 are sputtered, respectively. The film is formed by the method. Here, the Ru film 76 has such a thickness that the CoFe film 75 and the CoFe film 77 are antiferromagnetically coupled.

Subsequently, a resist is formed in the shape of TMR (magnetoresistive memory element 64) by photolithography, the SiO ₂ film 81 other than the resist is processed by selective ion processing (RIE), and the resist is removed by ashing. . Next, the Ta film 80 and the NiFe film 79 are removed by milling using the SiO ₂ film 81 pattern as a mask. Then, after forming a SiN film 82 as a protective film on the entire surface, a resist is formed in a BASE 86a shape, and a SiN film 82, MgO film 95, CoFe film 77, Ru film 76, CoFe film 75, PtMn film 74, NiFe film are formed. 73 and Ta film 72 are processed.
The magnetoresistive memory element 60a can be formed by the above manufacturing process.

  As in the case of the first embodiment, the MgO film 95 as the tunnel barrier layer, the CoFe film 77 / Ru film 76 / CoFe film 75 / PtMn film 74 / NiFe film 73 as the pinned layer, and the lower electrode The BASE 86 a including the Ta film 72 is a rectangle that is long in the extending direction (X direction) of the word line 50 (AlCu wiring 85). The NiFe film 79 as a free layer is formed on the BASE 86a and has an elliptical shape that is long in the extending direction of the word line 50 (X direction).

Thereafter, a SiO ₂ film 83 as an interlayer insulating film is formed on the entire surface by plasma CVD. Thereafter, the entire surface is flattened by a CMP technique. Subsequently, via holes penetrating the SiO ₂ film 83, the SiN film 82, and the SiO ₂ film 81 on the free layer (NiFe film 79) are formed by a photolithography technique and a dry etching technique, and a Cu via 84 is formed. . Thereafter, a Ti film (30 nm), an AlCu film (500 nm), and a TiN film (30 nm) are stacked and processed by a photolithography technique and a dry etching technique to form an AlCu wiring 85 as the word line 50.

Further, a 10 nm thick Ta film 119, a 18.5 nm thick NiFe film 126, a 0.8 nm thick Ru film 127, a 10 nm thick CoFe film 128, and a 10 nm thick Ta film 129 are formed on the entire surface. A film is formed by sputtering. Thereafter, a resist is formed in a thicker pattern with the same pattern as the AlCu wiring 85 and processed by milling. Thereby, YOKE 20b is formed so as to surround both side surfaces and the upper surface of the AlCu wiring 85. At this time, the Ru film 127 has such a thickness that the NiFe film 126 and the CoFe film 128 are antiferromagnetically coupled. As a result, the NiFe film 126 and the CoFe128 film are magnetized in opposite directions. The amounts of magnetization of the materials used here are NiFe: 800 emu / cm ³ and CoFe: 1480 emu / cm ³ , respectively. As a result, the NiFe film 126 and the CoFe film 128 are magnetized in opposite directions, and the amounts of magnetization of both are equal, so that there is almost no leakage magnetic field to the outside.

Next, a magnetic field of about 1000 to 10000 Oe is applied in the long side direction of the upper wiring (AlCu wiring 85) pattern. Thereby, the NiFe film 126 and the CoFe film 128 of the YOKE 20b provided in contact with the AlCu wiring 85 are oriented in the direction along the magnetic field. When the magnetic field is returned to zero, since the NiFe film 126 and the CoFe film 128 are antiferromagnetically coupled, the magnetization direction tends to be reversed. Since the AlCu wiring 85 is a long rectangle in the extending direction, the YOKE 20b also has a long rectangular shape. Therefore, in YOKE 20b, an easy axis is formed in the extending direction due to shape anisotropy. The NiFe film 126 and the CoFe film 128 have the same amount of magnetization, but the NiFe film 126 has a small anisotropic magnetic field of the material. Therefore, the CoFe film 128 is stabilized toward the long side direction axis close to the applied magnetic field direction, and the NiFe film 126 is stabilized in the opposite direction. Thereby, the magnetization direction of YOKE20b can be set to a desired direction.
Thus, a memory cell can be manufactured.

  Since the operation method (write method and read method) of the memory cell is the same as that of the first embodiment, the description thereof is omitted.

  In the above embodiment, the bit line is described as the lower side (semiconductor substrate side) and the word line is described as the upper side. However, the present invention is not limited to this, and the positional relationship between the bit line and the word line may be reversed.

  Also in this embodiment, the same effect as that of the first embodiment can be obtained. In addition, the process is relatively easy because a two-layer YOKE structure without a leakage magnetic field can be obtained.

  The magnetic laminated film may be formed not on the entire side surface of the wiring but on a part thereof. For example, in the second embodiment, a part of the wiring after the process is covered with a resist and milled to remove the magnetic laminated film on the upper surface of the wiring and leave it on the side surface. FIG. 12 is a top view of relevant parts showing another configuration of such wiring and YOKE 20b. FIG. 13 is a cross-sectional view along AA ′ in FIG. 12. 14 is a cross-sectional view taken along the line BB ′ in FIG.

  In FIG. 12, a region 26 is a region where the upper surface of the YOKE 20b is not removed because it is covered with a resist. The cross section AA 'has the same shape as that of FIG. 8, as shown in FIG. On the other hand, in FIG. 12, since the area | region 26 was not covered with the resist, it is an area | region from which the upper surface of YOKE20b was removed. As shown in FIG. 14, the cross section BB 'has a shape in which the upper part is deleted in FIG. For example, a magnetic field can be efficiently applied to the magnetoresistive memory element 60 by making the area having the magnetoresistive memory element 60 below the area 26.

(Third embodiment)
A third embodiment of the magnetic device and magnetic storage device of the present invention will be described with reference to the accompanying drawings. The principal part sectional view and the principal part plan view showing the configuration of the third embodiment of the magnetic device shown in FIG. 3 and FIG. 4 are the same as those of the first embodiment, and the description thereof will be omitted.

Next, a third embodiment of the magnetic device and the magnetic storage device of the present invention will be specifically described.
FIG. 9 is a schematic circuit block diagram showing the configuration of the third embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. FIG. 10 is a fragmentary cross-sectional view showing the configuration of the third embodiment of the memory cell as the magnetic device of the present invention. FIG. 11 is a plan view of the main part of the memory array of the third embodiment of the magnetic memory device to which the magnetic device of the present invention is applied. However, in FIG. 11, the selection transistors 65 and 66, the word lines 50a, 50b, and 50c, and the bit line 51d are not shown.

  First, the circuit configuration will be described with reference to FIG. The magnetic storage device 30a is a magnetic random access memory. The magnetic storage device 30a includes a plurality of word lines 50a, a plurality of word lines 50b, a plurality of word lines 50c, a plurality of bit lines 51c, a plurality of bit lines 51d, a plurality of memory cells 90, a word control circuit 144, and a write control circuit. 141, a write termination circuit 143, a bit line control circuit 57, a bit control circuit 145, and a sense amplifier 59.

  The plurality of word lines 50a extend in the X direction (first direction). The word line 50 a has one end connected to the write control circuit 141 and the other end connected to the source / drain of the selection transistor 66 of the memory cell 90. The word line 50a is shared by the memory cells 90 (select transistor 66) arranged along the extending direction (X direction). The plurality of word lines 50b extend in the X direction. The word line 50 b has one end connected to the gate of the selection transistor 65 of the memory cell 90 and the other end connected to the word control circuit 144. The word line 50b is shared by the memory cells 90 (select transistor 65) arranged along the extending direction (X direction). The plurality of word lines 50c extend in the X direction. One end of the word line 50 c is connected to the source / drain of the selection transistor 65 of the memory cell 90, and the other end is connected to the write termination circuit 143. The word line 50c is shared by the memory cells 90 (select transistor 65) arranged along the extending direction (X direction).

  The plurality of bit lines 51c extend in the Y direction (second direction orthogonal to the first direction). The bit line 51 c has one end connected to the bit line control circuit 57 and the other end connected to the magnetoresistive storage element 64 of the memory cell 90. The bit line 51c is shared by the memory cells 90 (magnetoresistance storage elements 64) arranged along the extending direction (Y direction). The plurality of bit lines 51d extend in the Y direction. The bit line 51d has one end connected to the gate of the selection transistor 66 of the memory cell 90 and the other end connected to the bit control circuit 145. The bit line 51d is shared by the memory cells 90 (select transistor 66) arranged along the extending direction (Y direction).

  The plurality of memory cells 90 are provided corresponding to the intersections of the plurality of word lines 50a and the plurality of bit lines 51c. The memory cell 90 includes a magnetoresistive storage element 64 and selection transistors 65 and 66. Here, the magnetoresistive memory element 64 is a tunnel magnetoresistive (TMR) element. The BASE 86b of the magnetoresistive storage element 64 extends in the X direction. The magnetoresistive memory element 64 has two terminals. One terminal is connected to the bit line 51c, and the other terminal is connected to the BASE 86b. One end of the BASE 86 b is connected to the source / drain of the selection transistor 65. The other source / drain of the selection transistor 65 is connected to the write termination circuit 143 via the word line 50c, and the gate is connected to the word control circuit 144 via the word line 50b. The other end of the BASE 86 b is connected to the source / drain of the selection transistor 66. The other source / drain of the selection transistor 66 is connected to the write control circuit 141 via the word line 50a, and the gate is connected to the bit control circuit 145 via the bit line 51d.

  The word control circuit 144 selects the selected word line 50b from the plurality of word lines 50b. The write control circuit 141 selects the selected word line 50a from the plurality of word lines 50a during the write operation. The write termination circuit 143 terminates the plurality of word lines 50c during the write operation and grounds the plurality of word lines 50c during the read operation. The bit line control circuit 57 selects the selected bit line 51c from the plurality of bit lines 51c during the read operation. The bit control circuit 145 selects the selected bit line 51d from the plurality of bit lines 51d during the write operation. The sense amplifier 59 is connected to the bit line control circuit 57, and performs data discrimination by comparing the bit line potential acquired via the bit line control circuit 57 with the reference potential Vref during a read operation.

Next, the configuration of the magnetoresistive storage element 64 of the memory cell 90 will be described with reference to FIG.
The magnetoresistive memory element 64 is a TMR element. Ta film 72 as a lower electrode, NiFe film 73 as a pin layer, PtMn film 74, CoFe film 75, Ru film 76 and CoFe film 77, AlO film 98 as a tunnel barrier layer, NiFe film 100 as a free layer, Ru A film 101, a NiFe film 102, and a Ta film 80 as an upper electrode are provided. Here, the lower structure of the magnetoresistive memory element 64 (NiFe film 73, PtMn film 74, CoFe film 75, Ru film 76, CoFe film 77, and Cu film 78) is also referred to as BASE 86b. The magnetoresistive storage element 64 corresponds to the functional body 4.

  The Ta film 72, which is the lower electrode, is provided with YOKE 20c as a magnetic laminated film on at least one side surface thereof. The Ta film 72 is connected to a semiconductor substrate (not shown) provided with a transistor including the selection transistors 65 and 66 and a wiring including a plurality of word lines 50a, (50b,) 50c through the YOKE 20b and the W via 70. Has been. The Ta film 80 that is the upper electrode is connected to the AlCu wiring 85 as the bit line 51 c via the Cu via 84.

  Here, the Ta film 72 corresponds to the conductor wiring 5. The Ta film 72 is provided with YOKE 20c on at least one of the three side surfaces excluding the surface on which the magnetoresistive storage element 64 is provided. The YOKE 20 c includes a stacked film of a Ta film 135, a NiFe film 130, a Ru film 131, a NiFe film 132, a Ru film 133, and a NiFe film 134 in order from the side close to the Ta film 72. Here, the NiFe film 130 corresponds to the magnetic body 2. The Ru film 131 corresponds to the antiferromagnetically coupled nonmagnetic conductor 3 (nonmagnetic conductor 11). The NiFe film 132 corresponds to the magnetic body 2. The Ta film 133 corresponds to the nonmagnetic conductor 11. The NiFe film 134 corresponds to the magnetic body 2.

Next, a method for manufacturing a memory cell will be described with reference to FIG.
First, transistors including select transistors 65 and 66 and wirings including a plurality of word lines 50a, 50b, and 50c are formed on a semiconductor substrate (not shown). Thereafter, a SiO ₂ film 71 as an interlayer insulating film is formed with a film thickness of 300 nm on the semiconductor substrate. A W via 70 is formed at a predetermined position of the SiO ₂ film 71. Next, for YOKE 20b, a Ta film 135 having a thickness of 5 nm, a NiFe film 130 having a thickness of 10 nm, a Ru film 131 having a thickness of 0.8 nm, a NiFe film 132 having a thickness of 20 nm, and a Ru film 133 having a thickness of 0.8 nm. A NiFe film 134 having a thickness of 10 nm is formed by sputtering. Furthermore, a Ta film 72 having a thickness of 100 nm, a NiFe film 73 having a thickness of 1 nm, a PtMn film 74 having a thickness of 10 nm, a CoFe film 75 having a thickness of 2 nm, a Ru film 76 having a thickness of 0.8 nm, and a CoFe film having a thickness of 2 nm. 77, a 1.5 nm thick AlO film 98, a 3 nm thick NiFe film 100, a 2.1 nm thick Ru film 101, a 3.5 nm thick NiFe film 102, a 30 nm thick Ta film 80, and A SiO ₂ film 81 having a thickness of 70 nm is formed by sputtering. Here, the Ru films 131 and 133 are formed to have such thicknesses that the NiFe films 130, 132, and 134 are antiferromagnetically coupled to each other. As a result, the NiFe films 130 and 134 are magnetized in one direction, and the NiFe film 132 is magnetized in the opposite direction. By setting the thickness so that the total magnetization amount of the NiFe films 130 and 134 is equal to the magnetization amount of the NiFe film 132, it is possible to eliminate almost any leakage magnetic field to the outside. Note that the Ru film 76 has a thickness at which the CoFe film 75 and the CoFe film 77 are antiferromagnetically coupled.

Subsequently, a resist is formed in the shape of TMR (magnetoresistive memory element 64) by photolithography technology, the SiO ₂ film 81 other than the resist is processed by selective ion processing technology, and the resist is removed by ashing. Next, the Ta film 80 and the NiFe film 79 are removed by milling using the SiO ₂ film 81 pattern as a mask. Then, after forming a SiN film 82 as a protective film on the entire surface, a resist is formed in a BASE 86b shape, and a SiN film 82, an AlO film 98, a CoFe film 77, a Ru film 76, a CoFe film 75, a PtMn film 74, and a NiFe film. 73, Ta film 72, NiFe film 134, Ru film 133, NiFe film 132, Ru film 131, NiFe film 130, and Ta film 135 are processed.
The magnetoresistive memory element 64 can be formed by the above manufacturing process.

  As shown in FIG. 11, an AlO film 98 as a tunnel barrier layer, a CoFe film 77 / Ru film 76 / CoFe film 75 / PtMn film 74 / NiFe film 73 as a pinned layer, and a Ta film 72 as a lower electrode. BASE86b including a rectangular shape that is long in the direction (X direction) substantially perpendicular to the extending direction (Y direction) of the bit line 51c (AlCu wiring 85). The NiFe film 102, the Ru film 101, and the NiFe film 100, which are free layers, are formed on the BASE 86b and have an elliptical shape that is long in a direction inclined by 45 ° from the extending direction (Y direction) of the bit line 51c. One end of the BASE 86b is connected to the diffusion layer 65a of the selection transistor 65 through the W via 70, and the other end is connected to the diffusion layer 66a of the selection transistor 66 through another W via. However, in FIG. 11, the other portions of the selection transistors 65 and 66, the bit line 51b, the word lines 50a, 50b, and 50c are not shown.

Thereafter, a SiO ₂ film 83 as an interlayer insulating film is formed on the entire surface by plasma CVD. Thereafter, the entire surface is flattened by a CMP technique. Subsequently, via holes penetrating the SiO ₂ film 83, the SiN film 82, and the SiO ₂ film 81 on the free layer (NiFe film 102) are formed by a photolithography technique and a dry etching technique, and a Cu via 84 is formed. . Thereafter, a Ti film (30 nm), an AlCu film (500 nm), and a TiN film (30 nm) are stacked and processed by a photolithography technique and a dry etching technique to form an AlCu wiring 85 as the bit line 51c.

Next, a magnetic field of about 1000 to 10000 Oe is applied in the long side direction of the BASE 86 b pattern. As a result, the three NiFe films 130, 132, and 134 of the YOKE 20c provided under the BASE 86b are oriented in the direction along the magnetic field. When the magnetic field is returned to zero, since the NiFe films 130 and 134 and the NiFe film 132 are antiferromagnetically coupled, the magnetization direction tends to be reversed. Since the pattern of the BASE 86b (the lower wiring Ta film 72) is a long rectangle in the extending direction, the YOKE 20c also has a long rectangular shape. Therefore, in YOKE 20c, an easy axis is formed in the extending direction due to shape anisotropy. The NiFe films 130 and 134 and the NiFe film 132 have the same amount of magnetization, but since the NiFe films 130 and 134 are divided into two, the anisotropic magnetic field is small. Therefore, the NiFe film 132 is stabilized toward the long side direction axis close to the applied magnetic field direction, and the NiFe films 130 and 134 are stabilized toward the opposite direction. Thereby, the magnetization direction of YOKE20c can be set to a desired direction.
Thus, a memory cell can be manufactured.

Next, an operation method of the memory cell will be described with reference to FIG. First, the writing method will be described.
The word control circuit 144 selects the selected word line 50b from the plurality of word lines 50b. Thereby, the selection transistor 65 on the selected word line 50b is turned on. The bit control circuit 145 selects the selected bit line 51d from the plurality of bit lines 51d. Thereby, the selection transistor 66 on the selected bit line 51d is turned on. As a result, both the selection transistors 65 and 66 are turned on only in the memory cell 90 (selected cell) at the position where the selected word line 50b and the selected bit line 51d intersect. The write control circuit 141 selects the selected word line 50a from the plurality of word lines 50a. The write termination circuit 143 selects the selected word line 50c from the plurality of word lines 50C. Both the selected word line 50a and the selected word line 50c are connected to the selected cell. By providing a potential difference between the write control circuit 141 and the write termination circuit 143, a write current can be supplied only to the BASE 86b of the selected cell. The magnetic field due to the write current flowing through the BASE 86b is collected in the YOKE 20c and efficiently applied to the free layers (NiFe film 102, Ru film 101, and FiFe film 100). Since the free layer is arranged to be inclined with respect to the write current flowing through the BASE 86b, the magnetization can be reversed only by the write current.

Next, a reading method will be described.
The word control circuit 144 selects the selected word line 50b from the plurality of word lines 50b. As a result, the select transistor 65 of the memory cell 52 (selected cell) to be read is turned on. The write termination circuit 143 selects the selected word line 50c from the plurality of word lines 50c. At that time, the write termination circuit 143 sets the selected word line 50c to the ground potential. The bit line control circuit 57 selects the selected bit line 15c from the plurality of bit lines 51c. When a voltage is applied to the selected bit line 50c by the bit line control circuit 57, a read current flows through a path of the selected bit line 51c, the magnetoresistive storage element 64, the selection transistor 65, the selected bit line 50c, and the ground (write termination circuit 143). . The magnitude of the read current varies depending on the resistance value (value of stored data) of the magnetoresistive storage element 64 of the memory cell 90 to be read. The bit line control circuit 57 converts the current value of the read current into a voltage and outputs the voltage to the sense amplifier 59 as the sense voltage Vs. To the sense amplifier 59, an intermediate value of voltages (V0 and V1) output by data values (“0” and “1”) is given as Vref. The sense amplifier 59 determines the data (either “0” or “1”) written in the memory cell 90 by comparing Vref and Vs.

  In the above embodiment, the word line is described as the lower side (semiconductor substrate side) and the bit line is described as the upper side. However, the present invention is not limited to this, and the positional relationship between the bit line and the word line may be reversed.

  According to the present embodiment, even in the YOKE provided in the BASE, the magnetization direction of the YOKE can be set in a desired direction, and the leakage magnetic field from the YOKE end that causes the characteristic variation can be suppressed. As a result, variation in magnetic properties of YOKE is reduced, and a magnetic storage device with a good yield can be obtained.

  In the above embodiment, the case where there are up to three magnetic layers in YOKE is shown. However, the present invention is not limited to this, and can be configured with four or more layers. Each magnetic layer is antiferromagnetically coupled or ferromagnetically coupled via a nonmagnetic conductor layer inserted between the magnetic layers. It is optional as long as it is not contrary to the technical idea of the invention.

  As described above, according to the present invention, it is possible to obtain a magnetic device having a small characteristic variation by suppressing the leakage magnetic field from YOKE formed in the wiring, thereby providing a magnetic device having a high yield. be able to.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention. In each of the above embodiments, a part of the technology can be used for other embodiments as long as no technical contradiction occurs.

  According to the present invention, it is possible to provide a magnetic body device and a magnetic memory device in which generation of a magnetic field is suppressed in the middle of the wiring having YOKE and at the end of the wiring. It is possible to provide a magnetic device and a magnetic storage device that can improve the manufacturing yield by suppressing variation in characteristics between TMR elements and reduce the manufacturing cost.

Claims (9)

A magnetic layered film provided along the wiring, facing at least one surface of the wiring of the conductor long in one direction,
A functional body that realizes a function by interaction with a magnetic field induced by a current flowing in the wiring,
The magnetic laminate film is
A plurality of magnetic layers;
And at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers,
The non-magnetic conductor layer ferromagnetically or antiferromagnetically couples the magnetic layers on both sides;
At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides;
The total amount of magnetization of the plurality of magnetic layers is substantially zero,
Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction The magnetic device is different. In the magnetic body device according to claim 1,
The plurality of magnetic layers are two magnetic layers,
The two magnetic layers are made of different materials or materials having different composition ratios. In the magnetic body device according to claim 1,
The plurality of magnetic layers are three or more layers. In the magnetic body device according to any one of claims 1 to 3,
A magnetic body device in which when a current is passed through the wiring, the magnetic field on the side without the magnetic layered film in the wiring is larger than the magnetic field on the side when the magnetic layered film is not provided. In the magnetic body device according to any one of claims 1 to 4,
The magnetic laminate film is
In the area on the wiring corresponding to the position of the functional body, provided facing a plurality of surfaces of the wiring,
A magnetic device provided in a region other than the region on the wiring corresponding to the position of the functional body so as to face a plurality of surfaces below the plurality of surfaces of the wiring. In the magnetic body device according to any one of claims 1 to 5,
The functional body is
A pinned layer with a fixed magnetization direction;
A free layer that is either a laminated magnetic layer in which a plurality of magnetic layers are laminated via a nonmagnetic layer or a single magnetic layer;
An intermediate layer provided between the pinned layer and the free layer, which is one of an insulating layer and a nonmagnetic layer;
With
Information is stored by a relative relationship between the magnetization direction of the pinned layer and the magnetization direction of the free layer. A plurality of first wires extending in a first direction;
A plurality of second wirings extending in the second direction;
A plurality of magnetic devices provided corresponding to each of the intersections of the plurality of first wirings and the plurality of second wirings and having one end connected to the corresponding first wiring;
Each of the plurality of magnetic devices is
A magnetic layered film provided along the first wiring so as to face at least one surface of the first wiring;
A magnetic device that stores information by interaction with a magnetic field induced by a current flowing in the first wiring,
The magnetic laminate film is
A plurality of magnetic layers;
And at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers,
The non-magnetic conductor layer ferromagnetically couples or antiferromagnetically couples the magnetic layers on both sides;
At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides;
The total amount of magnetization of the plurality of magnetic layers is substantially zero,
Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction Different magnetic storage devices. A plurality of first wires extending in a first direction;
A plurality of second wirings extending in the second direction;
A plurality of magnetic devices provided corresponding to each of the intersections of the plurality of first wirings and the plurality of second wirings, and having one end connected to the corresponding second wiring;
Each of the plurality of magnetic devices is
A magnetic layered film provided along the internal wiring facing at least one surface of the internal wiring connected to the first wiring;
A magnetic device that stores information by interaction with a magnetic field induced by a current flowing in the internal wiring,
The magnetic laminate film is
A plurality of magnetic layers;
And at least one nonmagnetic conductor layer provided between each of the plurality of magnetic layers,
The non-magnetic conductor layer ferromagnetically couples or antiferromagnetically couples the magnetic layers on both sides;
At least one of the nonmagnetic conductor layers antiferromagnetically couples the magnetic layers on both sides;
The total amount of magnetization of the plurality of magnetic layers is substantially zero,
Of the plurality of magnetic layers, the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the first direction and the magnitude of the anisotropic magnetic field of the magnetic layer group facing in the second direction opposite to the first direction Different magnetic storage devices. In the magnetic body device according to claim 7 or 8,
The magnetic device is:
A pinned layer with a fixed magnetization direction;
A free layer that is either a laminated magnetic layer in which a plurality of magnetic layers are laminated via a nonmagnetic layer or a single magnetic layer;
An intermediate layer provided between the pinned layer and the free layer, which is one of an insulating layer and a nonmagnetic layer;
With
Information is stored by a relative relationship between the magnetization direction of the pinned layer and the magnetization direction of the free layer.

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