JP4799983B2 - Magnetic memory, magnetic memory drive circuit, magnetic memory wiring method, and magnetic memory drive method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic memory which is excellent in random access performance for realizing low power consumption. <P>SOLUTION: This magnetic memory is configured by connecting a plurality of magnetic thin wires 101 adjacent in a column direction (x direction) in parallel in a matrix structure constituted of a plurality of magnetic thin wires 101. The memory is provided with wiring 103 for supplying currents from a power source, and a transistor 104 for switching the on/off of currents running through each of the magnetic thin wires for moving magnetic walls between the magnetic thin wires 101 and the intersection between wiring 102 and the wiring 103. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to an information recording / reproducing apparatus, and more particularly to a magnetic memory for recording / reproducing data using a magnetic moment in a magnetic domain in a magnetic wire. Specifically, the present invention relates to a magnetic memory capable of moving a magnetic domain in which data is recorded by an electric current, a magnetic memory drive circuit, a magnetic memory wiring method, and a magnetic memory drive method.

  Conventionally, non-volatile memories such as hard disk drives (HDD) and solid state random access memories (RAM) have been used in many products.

  As for the HDD, a large amount of data exceeding 100 GB (gigabytes) can be recorded at a low cost. However, in the HDD, the read / write head must be moved several nm away from the rotating recording medium. Therefore, if vibration is applied to the HDD, the head may physically damage the medium, and the HDD may fail.

  A solid random access memory (RAM) that can record 1 GB of data has been developed, but the unit price per 1 GB is higher than that of an HDD. Furthermore, a flash memory, which is a typical solid state random access memory (RAM), requires a time of 1 μsec or more when recording, which is a very long time compared to other memories. Furthermore, the number of times of rewriting in the flash memory is about 1 million times, and there is a problem that data recorded in the cell will be lost if more data is written.

  Other solid-state random access memories such as ferroelectric RAM (FeRAM), OUM (Ovonic Unified Memory), and MRAM (Magnetic RAM) have only a capacity of several MB.

  As described above, the nonvolatile memory element has no gap control or drive mechanism between a medium such as an HDD and a reproducing / reading element, has a low cost and has a recording capacity comparable to that of an HDD, and further has a number of rewrites. It is required to be unlimited.

  In order to overcome such problems, MRTM (Magnetic Race Track Memory) has been devised to record a large amount of information on a magnetic wire arranged in a direction perpendicular to a substrate. Since MRTM is described in detail in Patent Documents 1 and 2, it will be briefly introduced below.

  FIG. 9 is a configuration diagram of a unit cell of MRTM described in Patent Documents 1 and 2. The MRTM will be described with reference to FIG. The MRTM unit cell 900B includes a U-shaped magnetic wire 101 arranged vertically on a silicon substrate 120, a recording element 106, a reproducing element 107, and a power source for supplying a current 901 to the magnetic wire 101. ing.

  Further, the magnetic wire 101 is composed of a plurality of magnetic domains 903... Separated by physical cuts. Information “1” and “0” are recorded depending on the magnetization direction of each magnetic domain 903. That is, a large number of bit cells made of a magnetic material are stacked perpendicular to the substrate. For example, if magnetic domains having a length of 0.1 microns are formed on the magnetic fine wire 101 having a length of 10 microns, information of 100 bits can be stacked and recorded in the vertical direction.

  FIG. 10 is a schematic view of the main part of MRTM900. As shown in FIG. 10, the MRTM 900 is configured by electrically connecting a plurality of unit cells 900 </ b> B in series using a wiring 102.

  Next, a method for recording / reproducing information in MRTM will be described. As shown in FIG. 9, the magnetic wire 101 is divided into a recording area 904 that is an information recording area and a reserve area 905 that is the other area. The recording information is a magnetic domain in the recording area 904. 903.

  In the case of reproducing information, by passing a current 901 through the magnetic wire 101, the domain wall that delimits the magnetic domain 903 in which the information is recorded is moved from the recording area 904 to the reserved area 905, and information to be reproduced is obtained. The recorded magnetic domain 903 is moved to the upper part of the reproducing element 107. The current 901 is a pulse current, and the direction / distance in which the domain wall moves can be controlled by the direction / number of pulses.

  FIG. 11 is a diagram showing a recording / reproducing method of the magnetic memory. As shown in FIG. 11, the reproducing element 107 includes a TMR (Tunnel Magnetoresistivity) element 908, and the magnetization direction of the TMR element 908 in the free layer changes due to the magnetization of the magnetic domain 903 that has moved on the TMR element 908. To do. By detecting the direction of magnetization of the free layer by the TMR effect, information “1” and “0” can be read.

Also, when recording information, by passing a current 901 through the magnetic wire 101 as in the case of reproduction (see FIG. 9), the domain wall separating the magnetic domains 903 where information is recorded is changed from the recording area 904 to the reserved area. The magnetic domain 903 to be recorded is moved to the upper part of the recording element 106. Here, by passing a current through the recording element 106 and setting the direction of magnetization of the magnetic domain 903 above the recording element by a magnetic field generated thereby, information “1” and “0” are recorded.
US Pat. No. 6,834,005 US Patent Application Publication No. 2004/0251232

  By the way, the recording / reproducing speed of MRTM is 1 to 100 ns, which is equivalent to that of a conventional DRAM. In addition, since MRTM can record a large amount of information on a smaller chip area, the cost can be reduced. In addition, since it does not have a drive mechanism like HDD, it has the same reliability as existing semiconductors. Therefore, MRTM is expected to be applied as a universal memory that replaces all nonvolatile memories.

  However, in the conventional MRTM, as shown in FIG. 10, a magnetic thin wire is connected in series with a power supply. Therefore, there is a problem that the wiring resistance becomes very large and the power consumption when supplying current to the magnetic wire becomes large.

  Further, since the magnetic wires are connected in series, the same current is supplied to all the magnetic wires. Therefore, all the domain walls move in the same direction at the same time. Therefore, the conventional MRTM has the disadvantages that the domain wall of an arbitrary cell cannot be individually moved, the random accessibility is inferior, and the information processing speed is reduced.

  In general, an MRAM or the like has a structure in which a memory element and a select transistor are arranged at an intersection between a word line and a bit line in order to improve random accessibility. FIG. 12 is a diagram showing a cell array in the MRAM. When selecting a cell provided in the MRAM, a voltage is applied to the word line 801 and the bit line 802 to turn on the selection transistor 804 provided at the intersection of the word line 801 and the bit line 802. And As a result, a current flows from the bit line 802 to the ground 805 with respect to the memory element 803 arranged at the intersection of the word line 801 and the bit line 802 to which the voltage is applied, and the information of the memory element 803 is stored. Can be read.

  As described above, in the MRAM, a memory element in which a selection transistor is arranged is sandwiched between a bit line to which a voltage is applied and a word line, thereby enabling cell selection and improving information processing speed.

  However, as shown in FIG. 12, in the wiring method in the memory element such as the MRAM, the direction of the current flowing through the memory element cannot be changed because one side of the memory element is always connected to the ground.

  Furthermore, in MRTM, the domain wall must be moved in a desired direction by changing the direction of the current flowing through the magnetic wire as appropriate, so that the wiring method in the MRAM cannot be used.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a magnetic memory excellent in random accessibility and capable of realizing low power consumption, a magnetic memory drive circuit, a magnetic memory wiring method, And a method of driving a magnetic memory.

  In order to solve the above-described conventional problems, the magnetic memory of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by a series connection wiring. A magnetic memory for recording or reproducing information by moving a domain wall that partitions a plurality of magnetic domains formed in each of the plurality of magnetic thin wires by a current supplied from a power source, wherein the matrix A plurality of magnetic wires adjacent to each other in the column direction are connected in parallel, a parallel connection wiring for supplying current from the power supply, an intersection of the series connection wiring and the parallel connection wiring, and the plurality of magnetic thin wires A switching element capable of switching on / off of a current that moves the domain wall flowing in each of the magnetic thin wires. It is characterized by that example.

  An MRTM as a magnetic memory generally has a matrix structure composed of a plurality of magnetic wires, and a structure in which a plurality of magnetic wires adjacent to each other in the row direction of the matrix are connected in series by serial connection wiring. is doing. Then, information is recorded or reproduced by moving a domain wall that partitions a plurality of magnetic domains formed in each of the plurality of magnetic thin wires by a current supplied from a power source.

  However, the conventional MRTM has a problem in that power consumption increases because magnetic wires are connected in series to the power source. Further, the conventional MRTM has a problem that it is inferior in random accessibility because the domain wall of an arbitrary cell cannot be individually moved.

  According to the above configuration, the plurality of magnetic thin wires adjacent to each other in the column direction of the matrix are connected in parallel by the parallel connection wiring, and current is supplied from the power source to the magnetic thin wires through the parallel connection wiring. Therefore, according to the magnetic memory of the present invention, the resistance value due to the magnetic wire can be reduced as compared with the conventional MRTM, so that the power consumption can be reduced.

  Furthermore, according to the said structure, since the switching element is provided in each magnetic wire, the magnetic wall of arbitrary magnetic wires can be moved separately. Thereby, the random access property of the magnetic memory of the present invention is improved as compared with the conventional MRTM.

  Furthermore, in the magnetic memory having the above-described configuration, the parallel connection wiring provided in any magnetic thin wire of the plurality of magnetic thin wires is the same as the parallel connection wiring provided in the magnetic thin wire and the magnetic thin wire adjacent in the row direction of the matrix. It is preferable that

  According to the above configuration, since the parallel connection wiring is shared between the magnetic thin wires adjacent in the row direction of the matrix, the number of parallel connection wirings connecting the power source and each magnetic thin wire can be reduced. . As a result, more magnetic wires can be formed per unit area, so that the recording density can be improved.

  Moreover, the parallel connection wiring provided in the arbitrary magnetic thin wires in the plurality of magnetic thin wires may be different from the parallel connection wiring provided in the magnetic thin wires adjacent to the magnetic thin wires in the row direction of the matrix.

  According to the above configuration, each of the magnetic thin wires adjacent to each other in the row direction of the matrix is independently connected to the power source by the different parallel connection wiring. As a result, the magnetic wall can be moved by simultaneously supplying a current from the power source to a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix, so that the magnetic memory can be driven at high speed. .

  In addition, the magnetic memory of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by a series connection wiring. A magnetic memory that records or reproduces information by moving a domain wall that partitions a plurality of magnetic domains formed in each of the thin wires by a current supplied from a power source, wherein the plurality of magnetic thin wires connected in series Are connected in parallel to each other in the column direction in the matrix, a parallel connection wiring for supplying current from the power source, and the series connection wiring On / off of the current for moving the domain wall flowing in each of the magnetic thin wires is switched between the intersection with the parallel connection wiring and each of the plurality of aggregates. And a switching device which can be obtained may be characterized by comprising a.

  According to the above configuration, a plurality of aggregates adjacent to each other in the column direction in the matrix are connected in parallel by the parallel connection wiring, and current is supplied from the power source to each aggregate through the parallel connection wiring. Therefore, according to the magnetic memory of the present invention, the resistance value due to the magnetic wire can be reduced as compared with the conventional MRTM, so that the power consumption can be reduced.

  Furthermore, according to the above configuration, since the switching element is provided in each assembly, the domain walls of the magnetic wires included in the arbitrary assembly can be individually moved. Thereby, the random access property of the magnetic memory of the present invention is improved as compared with the conventional MRTM.

  In particular, according to the above configuration, since one switching element is provided for a plurality of magnetic wires, the number of switching elements can be reduced even by a configuration in which one switching device is provided for one magnetic wire. Can do. As a result, the cost of the magnetic memory can be reduced, and more magnetic wires can be formed per unit area to improve the recording density.

  Further, in the magnetic memory having the above-described configuration, the parallel connection wiring provided in an arbitrary aggregate in the plurality of aggregates may be parallel connection wiring provided in an aggregate adjacent to the aggregate in the row direction of the matrix. It is preferable that they are the same.

  According to the above configuration, the parallel connection wiring connected to the power source is shared between the assemblies adjacent in the row direction of the matrix, so the number of parallel connection wirings connecting the power source and each assembly is reduced. Can be reduced. As a result, more magnetic wires can be formed per unit area, so that the recording density can be improved.

  Moreover, the parallel connection wiring provided in the arbitrary aggregate in the plurality of aggregates may be different from the parallel connection wiring provided in the aggregate adjacent to the aggregate in the row direction of the matrix.

  According to the above configuration, each of the aggregates adjacent in the row direction of the matrix is independently connected to the power source by the different parallel connection wiring. As a result, it is possible to simultaneously supply current from the power supply to the plurality of aggregates adjacent to each other in the row direction of the matrix and move the domain wall, thereby enabling the magnetic memory to be driven at high speed. .

  A magnetic memory driving circuit according to the present invention is a magnetic memory driving circuit having the above-described configuration, and is characterized in that the direction of a current supplied from the power source to the magnetic thin wire can be changed.

  According to the drive circuit having the above configuration, the direction of the current supplied from the power source to the magnetic wire is changed, so that the moving direction of the domain wall in the magnetic wire can be changed. As a result, the magnetic domain in the magnetic wire is moved, and information can be recorded / reproduced with respect to the magnetic memory of the present invention.

  Also, the wiring method of the magnetic memory of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by serial connection wires. A magnetic memory wiring method for recording or reproducing information by moving a domain wall that partitions a plurality of magnetic domains formed in each of a plurality of magnetic thin wires by a current supplied from a power source, wherein A plurality of magnetic thin wires adjacent to each other in a direction are connected in parallel by a parallel connection wiring, a current is supplied from the power source to the magnetic thin wire through the parallel connection wiring, and the series connection wiring and the parallel connection wiring A switching element is provided between the intersection point and each of the plurality of magnetic thin wires, and the switching element causes the switching element to flow to each of the magnetic thin wires. It is characterized by switching the current on / off to move the domain walls.

  Also, the wiring method of the magnetic memory of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by serial connection wires. A magnetic memory wiring method for recording or reproducing information by moving a domain wall that partitions a plurality of magnetic domains formed in each of a plurality of magnetic thin wires by an electric current supplied from a power supply, and connected in series When the plurality of magnetic thin wires are regarded as one aggregate, a plurality of aggregates adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring, and the parallel connection wiring is connected from the power source. Current is supplied to the magnetic thin wire via the switching element between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of aggregates. Provided, it is characterized in that switching the current on / off for moving the domain walls flowing through each of the magnetic wire by the switching element.

  Further, the magnetic memory driving method of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring. A magnetic memory driving method for recording or reproducing information by moving a domain wall partitioning a plurality of magnetic domains formed in each of a plurality of magnetic thin wires by a current supplied from a power supply via a driving circuit. In the magnetic memory, a plurality of magnetic thin wires adjacent in the column direction in the matrix are connected in parallel by a parallel connection wiring, and current is supplied from the power source to the magnetic thin wire through the parallel connection wiring. A switching element is provided between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of magnetic thin wires. The magnetic memory is driven by switching on / off of the current for moving the magnetic domain wall flowing in each of the magnetic thin wires by the chucking element, and further switching the direction of the current for moving the magnetic domain wall by the drive circuit. It is a feature.

  Further, the magnetic memory driving method of the present invention has a matrix structure composed of a plurality of magnetic thin wires, and a plurality of magnetic thin wires adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring. A magnetic memory driving method for recording or reproducing information by moving a domain wall partitioning a plurality of magnetic domains formed in each of a plurality of magnetic thin wires by a current supplied from a power supply via a driving circuit. In the magnetic memory, when the plurality of magnetic thin wires connected in series are regarded as one aggregate, the plurality of aggregates adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring. A current is supplied from the power source to the magnetic wire through the parallel connection wiring, and an intersection of the series connection wiring and the parallel connection wiring; and the plurality of aggregates A switching element is provided between them, and the switching element switches on / off of the current that moves the magnetic domain wall flowing in each of the magnetic thin wires, and further, the current that moves the magnetic domain wall by the drive circuit is switched. The magnetic memory is driven by switching the direction.

  According to the wiring method or driving method of the magnetic memory having the above-described configuration, it is possible to obtain the same effects as the magnetic memory of the present invention.

  According to the present invention, it is possible to provide a magnetic memory that is excellent in random accessibility and can realize low power consumption.

[Embodiment 1]
Embodiments of the present invention will be described below with reference to the drawings. For convenience of explanation, members having the same configuration are denoted by the same reference numerals, and description of the members will not be repeated.

  FIG. 1 is a diagram showing a configuration of a main part of a magnetic memory 100 according to the present embodiment. As shown in FIG. 1, the unit cell in the magnetic memory 100 according to this embodiment includes a magnetic wire 101, a recording element 106 provided at the bottom of the magnetic wire 101, and a reproducing element 107. Further, the magnetic memory 100 includes wirings (serial connection wirings) 102... For connecting the magnetic thin wires 101 in series, wirings (parallel connection wirings) 103 disposed so as to be orthogonal to the magnetic thin wires 101, and transistors 104. , And wirings 105 for driving the transistors 104. The plurality of magnetic thin wires 101 are arranged in a matrix on the same plane of the substrate 120.

  Furthermore, magnetic domains 903... (See FIG. 9) separated by physical cuts are formed on the magnetic wire 101 made of a magnetic material, as in the MRTM described in Patent Documents 1 and 2 shown in FIG. Has been. The magnetic memory 100 records information “1” “0” according to the magnetization direction of each magnetic domain 903.

  As shown in FIG. 1, the wirings 102 connecting the magnetic thin wires 101 in series are extended in the row direction of the matrix (x-axis direction in FIG. 1). Further, the wirings 103 arranged so as to be orthogonal to the magnetic fine wires 101 are extended in the column direction of the matrix (y-axis direction in FIG. 1).

  As shown in FIG. 1, one wiring 103 is disposed between adjacent unit cells. That is, the wiring 102 connecting the magnetic thin wires 101 in series and the wiring 103 orthogonal to the magnetic thin wires 101 are formed in a lattice shape.

  Further, as shown in FIG. 1, one transistor 104 is formed at one end of each magnetic wire 101. Further, the wiring 105 for applying a gate voltage to the transistor 104 is arranged in the x-axis direction in FIG. 1 so as to be parallel to the wiring 102 connecting the magnetic thin wires 101 in series.

  By controlling the direction of the current flowing through each of the wires 102 connected in series with the magnetic wires 101 and the wires 103 arranged so as to be orthogonal to the magnetic wires 101, the direction of the current flowing through the magnetic wires 101 is controlled. The domain wall formed in the magnetic wire 101 can be moved in a desired direction.

  Further, by controlling on / off of the transistor 104 and supplying a current to a desired location, only the domain wall formed in the desired magnetic wire 101 can be moved. The setting operation of the direction of the current flowing through the wiring and the moving direction of the domain wall will be described later.

  Here, the material of the wiring 102 connecting the magnetic thin wires 101 in series and the wiring 103 arranged so as to be orthogonal to the magnetic thin wires 101 may be appropriately selected according to the configuration of the magnetic memory 100 and the like. For example, it can be said that metal wiring such as copper, aluminum, nickel, and platinum is preferable because the electrical resistance is low and the cross-sectional area can be reduced and the power consumption can be reduced.

  On the other hand, as a material for forming the magnetic wire 101, a magnetic material exhibiting ferromagnetism (ferromagnetism or ferrimagnetism) in which magnetic energy (magnetization), exchange interaction energy, magnetic anisotropy energy, and damping coefficient are appropriately selected. It is desirable that Typical examples of these magnetic materials include B, Zr, Hf, Cr, Pd, and Pt added to permalloy, FeNi alloy, CoFe alloy, Ni, Fe, Co alloy, and Ni, Fe, Co alloy. Magnetic material. In addition, there are rare earth-transition metal alloys.

The magnetic wire 101 made of a magnetic material (for example, NiFe alloy (permalloy)) forms a Si, SiO ₂ , Si ₃ N ₄ film or the like on a Si substrate, and forms a high aspect ratio hole called a trench. After that, a magnetic material is filled in it.

  The trench has, for example, a cross section of 100 nm × 100 nm and a depth of 0.5 μm to 10 μm. The cross-sectional shape of the trench may be circular or square. As a method of forming a trench and filling a magnetic material, for example, there is a method of forming a trench using a semiconductor etching method used in a DRAM manufacturing process and then filling a magnetic material using a plating method. . Furthermore, all the components of the magnetic memory 100 according to the present embodiment can be manufactured using a semiconductor process.

  Furthermore, as shown in FIG. 2, the terminals 1a, 1b, and 1c of the wiring 103 arranged so as to be orthogonal to the magnetic thin wires 101 (101a to 101f) and the terminals of the drive circuit 108 are electrically connected. Yes. The drive circuit 108 includes switches 2a, 2b, 2c, 2d, 2e, and 2f. The switches 2a, 2c, and 2e are electrically connected to a positive potential (terminal) of the power source. The switches 2b, 2d, and 2f are electrically connected to the ground potential.

  The switches 2a to 2f are switches using field effect transistors. Further, although not shown, the switches 2a to 2f are operated by known control means, and each of the terminals 1a to 1c connected to the drive circuit 108 is connected to the positive potential of the power supply or to the ground potential. , Or can be switched. That is, whether the terminals 1a to 1c are short-circuited (connected) to the plus, short-circuited (connected) to the minus, or open to be connected to neither plus / minus by the operation of the switches 2a to 2f. Can be switched.

  FIG. 3 shows a cross-sectional view taken along the line A-A ′ in FIG. 2. As shown in FIG. 3A, the transistor 104 in the magnetic memory 100 according to the present embodiment is disposed at a position where the wiring 102 and the wiring 103 intersect on the upper surface of the magnetic wire 101. In addition, as shown in FIG. 3B, the transistor 104 may be formed on the substrate surface, and the transistor 104 and the magnetic wire 101 may be connected by a conductor wiring 130 in which a conductor is filled in the trench. Further, as shown in FIG. 3 (c), the upper and lower sides of the magnetic wire 101 may be formed in reverse to the configuration shown in FIG. 3 (a).

  Next, a method for driving the magnetic memory 100 according to the present embodiment will be described with reference to FIG.

  For example, it can be said that the terminal 1a is in the “open state” when both the switches 2a and 2b are in the off state. Further, when the switch 2a is in the on state and the switch 2b is in the off state, it can be said that the terminal 1a is “short-circuited positively”. When the switch 2a is in the off state and the switch 2b is in the on state, the terminal 1a is “ It's shorted to the minus. "

  In this manner, the driving circuit 108 can switch whether the terminals 1a to 1c are connected to the positive potential of the power source, connected to the ground potential, or opened, and the wiring 103 is connected in accordance with the switching pattern. A desired voltage difference can be applied between them.

  Further, the transistors 104a to 104f on the wiring 102 perform a switching function for selecting the magnetic thin wires 101a to 101f through which current flows. That is, a current corresponding to the voltage difference between the wirings 103 connected to both ends of the magnetic material flows only in the magnetic wires 101a to 101f in which the transistors connected to the transistors are turned on. Thereby, it becomes possible to move the domain wall of only the specific magnetic wire among the magnetic wires 101a to 101f.

  For example, the switches 2a and 2d in the drive circuit 108 are turned on and the switches 2b and 2c are turned off. Further, the transistors 104a to 104c are turned on, and the transistors 104d to 104f are turned off.

At this time, current flows through the following three paths.
(1) terminal 1a → intersection point a → magnetic wire 101a → intersection point d → terminal 1b → ground (2) terminal 1a → intersection point a → magnetic thin wire 101b → intersection point o → terminal 1b → ground (3) terminal 1a → intersection point c → magnetic Thin wire 101c → intersection point → terminal 1b → ground That is, in the magnetic thin wires 101a to 101c, a current flows in the positive direction of the x-axis. Therefore, the domain walls in the magnetic wires 101a to 101c move in the negative direction of the x axis.

  Note that the domain wall is described as moving in the direction opposite to the direction of current flow. Depending on the type of magnetic material of the magnetic wire 101, the magnetic wire 101 may move in the same direction as the current flows.

  Conversely, the switches 2b and 2c are turned on, and the switches 2a and 2d are turned off. Further, the transistors 104a to 104c are turned on, and 104d to 104f are turned off.

At this time, current flows through the following three paths.
(1) Terminal 1b → Intersection point d → Magnetic wire 101a → Intersection point a → Terminal 1a → Ground (2) Terminal 1b → Intersection point o → Magnetic wire 101b → Intersection point a → Terminal 1a → Ground (3) Terminal 1b → Intersection point → Magnetic Thin wire 101c → intersection point C → terminal 1a → ground That is, in the magnetic thin wires 101a to 101c, a current flows in the negative direction of the x-axis. Therefore, the domain walls in the magnetic wires 101a to 101c move in the positive direction of the x axis.

  When it is desired to limit the number of magnetic thin wires through which current flows, for example, the switches 2a and 2d in the drive circuit 108 are turned on and the switches 2b and 2c are turned off. Further, only the transistor 104a is turned on, and the transistors 104b to 104f are turned off. As a result, current flows only through one path of terminal 1a → intersection point a → intersection point d → terminal 1b → ground.

  That is, a current flows only in the magnetic thin wire 101a in the positive x-axis direction. As a result, only the domain wall of the magnetic wire 101a moves in the negative direction of the x axis. Similarly, it is also possible to move the domain wall by causing a current to flow only in the magnetic thin wires 101b and 101c in a desired direction.

  On the other hand, the switches 2c and 2f are turned on, and the switches 2d and 2e are turned off. Further, the transistors 104d to 104f are turned on, and the transistors 104a to 104c are turned off.

At this time, current flows through the following three paths.
(1) Terminal 1b → Intersection point d → Magnetic wire 101d → Intersection point key → Terminal 1c → Ground (2) Terminal 1b → Intersection point o → Magnetic wire 101e → Intersection point → Terminal 1c → Ground (3) Terminal 1b → Intersection point → Magnetic Thin wire 101f → intersection point → terminal 1c → ground That is, a current flows in the magnetic thin wires 101d to 101f in the positive direction of the x-axis. Therefore, the domain walls in the magnetic wires 101d to 101f move in the negative direction of the x axis.

  Conversely, the switches 2d and 2e are turned on, and the switches 2c and 2f are turned off. Further, the transistors 104d to 104f are turned on, and the transistors 104a to 104c are turned off.

At this time, current flows through the following three paths.
(1) Terminal 1c → Intersection point → Magnetic wire 101d → Intersection point → Terminal 1b → Ground (2) Terminal 1c → Intersection point → Magnetic wire 101e → Intersection point o → Terminal 1b → Ground (3) Terminal 1c → Intersection point → Magnetic Thin wire 101f → intersection point → terminal 1b → ground That is, in the magnetic thin wires 101d to 101f, a current flows in the negative direction of the x-axis. Therefore, the domain walls in the magnetic wires 101d to 101f move in the positive direction of the x axis.

  In this way, if the connection pattern of the switches 2a to 2f is changed, a current can be passed through the desired magnetic wire 101 from a desired direction, and the domain wall of the desired magnetic wire 101 can be moved. Become.

  As described above, information can be recorded or reproduced on the desired magnetic wire 101 by controlling the direction of the current flowing in the desired magnetic wire 101 and moving the domain wall. This will be further described with reference to FIG.

  When reproducing information, the magnetic thin wire 101 from which information is reproduced is selected by the on / off operation of the driving circuit 108 and the transistor 104 described above, and the domain wall is moved in a desired direction. As a result, the magnetic domain in which information to be reproduced is recorded is moved to the upper part of the reproducing element 107 (see FIG. 1).

  Here, the reproducing element 107 includes a TMR element 908 as shown in FIG. 11, and the magnetization direction of the free layer in the TMR element 908 depends on the magnetization direction of the magnetic domain 903 that has moved onto the TMR element 908. Change. By detecting the magnetization direction of the free layer by the TMR effect, information “1” and “0” can be read.

  In the case of recording information, the magnetic wire 101 for reproducing information is selected by the on / off operation of the drive circuit 108 and the transistor 104, and the domain wall is moved in a desired direction as in the case of reproducing. As a result, the domain wall that delimits the magnetic section in which information is recorded is moved, and the magnetic domain to be recorded is moved to the upper part of the recording element 106. Then, a current is passed through the wiring that is the recording element 106, and the magnetization direction of the magnetic domain in the upper part of the recording element is set by a magnetic field generated thereby, thereby recording “1” and “0”.

  However, current cannot flow simultaneously to adjacent magnetic wires 101 (magnetic wires 101 adjacent in the x direction) connected to the same wiring 102. The reason for this will be described below with reference to FIG.

  Consider magnetic thin wires 101a and 101d as examples of magnetic thin wires adjacent in the x direction. When a current is passed through the magnetic thin wire 101a in the positive direction of the x-axis, the current flows in the direction of terminal 1a → intersection point a → intersection point d → terminal 1b. On the other hand, when a current flows in the magnetic thin wire 101d in the positive direction of the x-axis, the current flows in the direction of terminal 1b → intersection point → intersection point → terminal 1c.

  However, it is physically impossible to pass currents in different directions within a single wiring. That is, it is impossible to realize the current in the direction from the intersection point D to the terminal 1 b and the current in the direction from the terminal 1 b to the intersection point D on the same wiring 103. Therefore, it can be seen that the adjacent magnetic thin wires 101a and 101d cannot be driven simultaneously. Even if the magnetic wires 101a and 101d arranged adjacent to each other with other wiring patterns are to be driven at the same time, a physical contradiction may occur in the flow of current.

  Therefore, when actually driving the magnetic memory 100 according to the present embodiment, it is necessary to employ a time-division scanning method in which the individual magnetic wires 101 are driven with a predetermined time difference.

  As described above, the magnetic memory 100 of this embodiment has a matrix structure including a plurality of magnetic thin wires 101..., And the plurality of magnetic thin wires 101 adjacent to each other in the row direction (x direction) of the matrix are formed by the wiring 102. Information is recorded or reproduced by moving the domain walls that are connected in series and partition a plurality of magnetic domains formed in each of the plurality of magnetic thin wires 101 by a current supplied from a power source. In the matrix, a plurality of magnetic thin wires 101a to 101c adjacent to each other in the column direction (y direction) are connected in parallel, and a wiring 103 for supplying a current from the power source, a wiring 102, a wiring 103, etc. On / off of the current for moving the domain wall flowing in each of the magnetic thin wires is between the intersection of each of the plurality of magnetic thin wires 101. Ri be those which comprises transistors 104 ... a can be changed.

  According to the above configuration, current can be supplied from a desired direction to a desired magnetic wire 101 from among the magnetic wires 101 arranged in a matrix using the on / off control of the transistor 104. As a result, the domain walls of each magnetic wire 101 can be moved independently, further improving random accessibility and increasing the information processing speed. Moreover, since the magnetic thin wire | line 101 is connected in parallel by the wiring 103 extended in ay direction (refer FIG. 1 and FIG. 2), the wiring resistance between each terminal 1a-1c has the structure which connects a magnetic thin wire in series ( (See FIG. 10). Thereby, power consumption can be reduced.

  Further, in the magnetic memory 100, for example, the wiring 103 provided at both ends of the magnetic wire 101a is the same as the wire 103 that connects the magnetic wire 101a and the magnetic wire 101d adjacent in the row direction (x direction) of the matrix to the power source. is there.

  That is, since the wiring connected to the power supply is shared between the magnetic thin wires 101a and 101d adjacent in the row direction of the matrix, the number of wirings 103 connecting the power supply and each magnetic thin wire 101 can be reduced. Can do. As a result, more magnetic wires can be formed per unit area, so that the recording density can be improved.

[Embodiment 2]
Next, another embodiment of the present invention will be described. FIG. 4 is a schematic view of the main part of the magnetic memory 200 according to the present embodiment. The components of the magnetic memory 200 are generally the same as those described in the first embodiment.

  In the magnetic memory 200 according to the present embodiment, as shown in FIG. 4, each of the magnetic wires 101 is arranged in parallel to the power supply by wires 103 arranged so as to be orthogonal to the magnetic wires 101. It can be said that it is connected.

  That is, in the y direction shown in FIG. 4, three magnetic thin wires 101 are provided adjacent to each other. When the aggregates of the magnetic wires composed of the three magnetic wires 101 are described as the assemblies 110a and 110b, two wirings 103 for connecting the magnetic wires in parallel are provided for each of the assemblies 110a and 110b. It has been.

  In the present embodiment, the terminals 1a to 1e of the wiring 103 are independently short-circuited (connected) to plus or minus, whereby all the wirings can be energized simultaneously.

  That is, in this embodiment, since two wirings 103 are connected to one magnetic wire 101, the number of magnetic wires 101 that can be formed per unit area is reduced as compared to the first embodiment. Recording density will decrease.

  However, in the magnetic memory 100 according to the first embodiment, current cannot flow simultaneously to the magnetic thin wires 101 adjacent in the x-axis direction, whereas in the magnetic memory 200 according to the present embodiment, a large number of magnetic fields can be obtained in one operation. It is possible to control the current direction in the thin wire 101. Therefore, it can be said that the magnetic memory 200 of the present embodiment is a more preferable configuration in terms of high speed. This point will be specifically described below.

  FIG. 5 is a diagram showing a drive circuit connected to the magnetic memory 200 according to the present embodiment. As shown in FIG. 5, the drive circuit 108 connected to the magnetic memory 200 according to the present embodiment is provided with switches 2 a to 2 h connected to the terminals 1 a to 1 d of the wirings 103. The switches 2a, 2c, 2e, and 2g are electrically connected to a positive potential (terminal) of the power source. The switches 2b, 2d, 2f, and 2h are electrically connected to the ground potential.

  FIG. 6 shows a cross-sectional view along A-A ′ in FIG. 5. As shown in FIG. 6A, the transistor 104 in the magnetic memory 200 according to the present embodiment is disposed at a position where the wiring 102 and the wiring 103 intersect on the upper surface of the magnetic wire 101. Further, as shown in FIG. 6B, the transistor 104 may be formed on the substrate surface and connected to the magnetic thin wire 101 by the conductor wiring 130 in which the conductor is filled in the trench. Moreover, as shown in FIG.6 (c), you may form the upper and lower sides of the magnetic wire 101 contrary to the structure shown to Fig.6 (a).

  Next, a method for driving the magnetic memory 200 according to the present embodiment will be described with reference to FIG.

  For example, the switches 2a, 2d, 2e, and 2h are turned on, and the switches 2b, 2c, 2f, and 2g are turned off. Furthermore, if all of the transistors 104d to 104f arranged at the end of the magnetic wire 101 are turned on, current flows in the positive direction of the x-axis in all the magnetic wires 101a to 101f. Therefore, the domain walls in the magnetic wires 101a to 101f move toward the negative direction of the x axis.

  In the present embodiment, as in the first embodiment, it is assumed that permalloy is used as the magnetic wire material, and the domain wall moves in the direction opposite to the direction of current flow. Depending on the type of magnetic material of the magnetic wire 101, the domain wall may move in the same direction as the current flows.

  Further, the switches 2a, 2d, 2f, and 2g are turned on, and the switches 2b, 2c, 2e, and 2h are turned off. Further, when all of the transistors 104d to 104f arranged at the end of the magnetic wire 101 are turned on, a current flows in the positive direction of the x-axis through the magnetic wires 101a to 101c, and the x-axis is supplied to the magnetic wires 101d to 101f. Current flows in the negative direction. Thereby, the domain walls in the magnetic wires 101a to 101c move in the negative direction of the x axis, while the domain walls in the magnetic wires 101d to 101f move in the positive direction of the x axis.

  In the above description, the transistors 104a to 104f are all turned on. However, by selectively turning off the transistors 104a to 104f, a current is supplied only to a desired magnetic wire and the domain wall is moved. It is possible.

  As described above, information can be recorded or reproduced using the method described in the first embodiment by controlling the direction of the current flowing in the magnetic wire 101 belonging to the desired aggregate 110 and moving the domain wall. it can.

  Thus, the magnetic memory 200 of this embodiment has a matrix structure composed of a plurality of magnetic wires 101a to 101f, and a plurality of magnetic wires adjacent in the row direction (x direction) of the matrix are connected in series by the wiring 102. A magnetic memory that records or reproduces information by moving a domain wall that partitions a plurality of magnetic domains formed in each of the plurality of magnetic thin wires by a current supplied from a power source, In the matrix, a plurality of magnetic thin wires 101a to 101c adjacent in the column direction (y direction) are connected in parallel, and an intersection of a wiring 103 for supplying a current from the power source, a wiring 102, and a wiring 103 Between each of the plurality of magnetic thin wires 101 and each of the plurality of magnetic thin wires 101... Ri be those that has a transistor 104 which can be changed.

  According to the above configuration, current can be supplied from a desired direction to a desired magnetic wire 101 from among the magnetic wires 101 arranged in a matrix using the on / off control of the transistor 104. As a result, the domain walls of each magnetic wire 101 can be moved independently, further improving random accessibility and increasing the information processing speed. Further, since the magnetic thin wires 101 are connected in parallel by the wiring 103 extending in the y direction (see FIG. 5), the wiring resistance between the terminals 1a to 1c is configured to connect the magnetic thin wires in series (see FIG. 10). ). Thereby, power consumption can be reduced.

  Further, in the magnetic memory 200, for example, the wiring 103 provided at both ends of the magnetic thin wire 101a is different from the wiring 103 connecting the magnetic thin wire 101a and the magnetic thin wire 101d adjacent in the row direction (x direction) of the matrix to the power source. .

  Thus, by simultaneously energizing the magnetic thin wires 101a and 101d adjacent to the y direction (see FIGS. 4 and 5), the current direction of a large number of magnetic thin wires 101 is set by one energization operation, and the domain wall is moved. It is possible. Therefore, according to the magnetic memory 200 of the present embodiment, the driving speed can be further increased.

[Embodiment 3]
FIG. 7 shows a plan view of the main part of a magnetic memory 300 according to still another embodiment of the present invention. Each element constituting the magnetic memory 300 is the same as that described in the first and second embodiments.

  In particular, in the magnetic memory 300 according to the present embodiment, the wiring 103 arranged so as to be orthogonal to the magnetic thin wire 101 in the configuration of the first embodiment has a plurality of magnetic thin wires 101 connected in series as shown in FIG. Are arranged one by one between the aggregates 110 (110a to 110f) of magnetic fine wires tied to each other.

  In FIG. 7, it is described that one aggregate 110 is constituted by three magnetic thin wires 101, but the number of magnetic thin wires constituting the aggregate is not limited to this, One aggregate 110 may be formed of at least two or more magnetic wires.

  In the first and second embodiments, one transistor 104 is arranged for one magnetic wire 101. However, considering the increase in capacity and miniaturization of the memory, this one magnetic wire-1 transistor configuration has a cost. This is disadvantageous from the viewpoint of recording capacity.

  Therefore, the magnetic memory 300 of the present embodiment is configured to perform current control by arranging a plurality of magnetic thin wires 101 as one aggregate and arranging transistors for each aggregate. Thereby, the number of transistors is reduced, and the recording density can be improved.

  The magnetic memory 300 according to the present embodiment allows a current to flow through a desired assembly 110 to which a current is to be supplied by a switch operation of wiring similar to that described in the first embodiment, and the magnetic wall of the magnetic thin wire through which the current is supplied. Can be moved.

  For example, the switches 2a and 2d are turned on, and the switches 2b, 2c, 2e, and 2f are turned off. Further, when the transistors 104a to 104c arranged at the ends of the aggregate 110 are turned on, a current flows through the aggregates 110a to 110c in the positive direction of the x axis. Therefore, the domain walls in the aggregates 110a to 110c move in the negative direction of the x axis.

  In the present embodiment, it is assumed that permalloy is used for the magnetic wire material as in the first embodiment, and the domain wall moves in the direction opposite to the direction of current flow. Depending on the type of magnetic material of the magnetic wire 101, the magnetic wire 101 may move in the same direction as the current flows.

  Further, the switches 2c and 2f are turned on, and the switches 2a, 2b, 2d, and 2e are turned off. Further, when the transistors 104d to 104f arranged at the ends of the aggregate 110 are turned on, a current flows through the aggregates 110d to 110f in the positive direction of the x axis. Therefore, the domain walls in the aggregates 110a to 110c move in the positive direction of the x axis.

  Note that in the above description, the case where all the transistors 104a to 104f are on is described. However, by selectively turning off the transistors 104a to 104f, a current is supplied only to a desired assembly. It is also possible to move the domain walls of the magnetic wires belonging to the aggregate.

  As described above, the magnetic memory 300 according to this embodiment has a matrix structure including a plurality of magnetic thin wires 101..., And a plurality of magnetic thin wires 101 adjacent to each other in the row direction (x direction) of the matrix are formed by the wiring 102. Information is recorded or reproduced by moving the domain walls that are connected in series and partition a plurality of magnetic domains formed in each of the plurality of magnetic thin wires by a current supplied from a power source, When the plurality of magnetic thin wires 101 connected in series are regarded as one aggregate 110, a plurality of aggregates 110 adjacent to each other in the column direction (y direction) in the matrix are connected in parallel. Between the wiring 103 for supplying a current from the power source, the intersection of the wiring 102 and the wiring 103, and each of the plurality of magnetic thin wires 101. In which includes a transistor 104 which can switch the current on / off for moving the domain walls through the respective sex thin line.

  According to the above configuration, the aggregate 110 of the magnetic thin wires 101 is connected in parallel to the power supply by the wiring 103. Therefore, according to the magnetic memory 300 of the present embodiment, the resistance value due to the magnetic wire can be reduced as compared with the conventional MRTM, so that the power consumption can be reduced.

  Further, according to the above configuration, since the transistor 104 is provided in each aggregate 110, the domain walls of the magnetic wires 101 included in the arbitrary aggregate 110 can be individually moved. Thereby, the random access property of the magnetic memory 300 is improved as compared with the conventional MRTM.

  In this manner, according to the magnetic memory 300 of the present embodiment, the method described in the first embodiment is used for recording or reproducing information by controlling the direction of the current flowing in the magnetic wire 101 and moving the domain wall. Can be done.

  In particular, according to the magnetic memory 300 of this embodiment, the transistor 104 is provided for each aggregate 110 of magnetic wires in which at least two or more magnetic wires 101 are connected in series. Accordingly, the number of transistors 104 can be reduced, and cost reduction can be realized.

  In the magnetic memory 300 of the present embodiment, for example, the wirings 103 provided at both ends of the assembly 110a connect the assembly 110a and the assembly 110d adjacent in the row direction (x direction) of the matrix to the power source. It is the same as the wiring 103.

  According to the above configuration, since the wiring connected to the power supply is shared between the assemblies 110a and 110d adjacent in the row direction (x direction) of the matrix, the wiring connecting the power supply and each assembly. Can be reduced. As a result, more magnetic wires can be formed per unit area, so that the recording density can be improved.

[Embodiment 4]
FIG. 8 shows a plan view of the main part of a magnetic memory 400 according to still another embodiment of the present invention. Each element constituting the magnetic memory 400 is the same as that described in the first to third embodiments.

  In particular, in the magnetic memory 400 according to the present embodiment, the aggregates 110a to 110f constituted by the three magnetic thin wires 101 adjacent to each other are connected to the power source by the wiring 103 arranged so as to be orthogonal to the magnetic thin wires 101. Are connected in parallel. By short-circuiting the terminals 1a to 1d of the wiring 103 independently to plus or minus, all the wirings can be energized simultaneously.

  8, the drive circuit 108 connected to the magnetic memory 400 is provided with switches 2a to 2h connected to the terminals 1a to 1d of the wirings 103. The switches 2a, 2c, 2e, and 2g are electrically connected to a positive potential (terminal) of the power source. The switches 2b, 2d, 2f, and 2h are electrically connected to the ground potential.

  In the third embodiment, for the same reason as in the first embodiment, it is difficult to simultaneously supply current to the aggregate 110 adjacent in the x-axis direction. On the other hand, the magnetic memory 400 of the present embodiment can be said to be a more preferable configuration in that all the wirings 103 can be energized at the same time and the current direction can be controlled.

  That is, the magnetic memory 400 according to the present embodiment supplies a current to the desired aggregate 110 by moving the wirings similar to that described in the second embodiment, and moves the domain wall of the magnetic thin wire through which the current flows. It becomes possible.

  For example, the switches 2a, 2d, 2e, and 2h are turned on, and the switches 2b, 2c, 2f, and 2g are turned off. Furthermore, if all the transistors 104a to 104f arranged at the ends of the aggregates 110a to 110f are turned on, a current flows through the aggregates 110a to 110f in the positive direction of the x axis. Thereby, the domain walls in the aggregates 110a to 110f move toward the negative direction of the x axis.

  In the present embodiment, it is assumed that permalloy is used for the magnetic wire material as in the first embodiment, and the domain wall moves in the direction opposite to the direction of current flow. Depending on the type of magnetic material of the magnetic wire 101, the magnetic wire 101 may move in the same direction as the current flows.

  Further, the switches 2a, 2d, 2f, and 2g are turned on, and the switches 2b, 2c, 2e, and 2h are turned off. Further, if all of the transistors 104a to 104f arranged at the end of the aggregate 110 are turned on, current flows in the positive direction of the x axis in the aggregates 110a to 110c, and the x axis of the aggregates 110d to 110f. A current flows in the negative direction.

  As a result, the domain walls in the aggregates 110a to 110c move in the negative direction of the x axis. On the other hand, the domain walls in the aggregates 110d to 110f move in the positive direction of the x axis.

  In the above description, the case where all of the transistors 104a to 104f are in the on state has been described. However, by selectively turning off the transistors 104a to 104f, current is supplied only to a desired aggregate, It is also possible to move it.

  As described above, the magnetic memory 400 of this embodiment has a matrix structure including a plurality of magnetic thin wires 101..., And the plurality of magnetic thin wires 101 adjacent to each other in the row direction (x direction) of the matrix are formed by the wiring 102. Information is recorded or reproduced by moving the domain walls that are connected in series and partition a plurality of magnetic domains formed in each of the plurality of magnetic thin wires by a current supplied from a power source, When the plurality of magnetic thin wires 101 connected in series are regarded as one aggregate 110, a plurality of aggregates 110 adjacent to each other in the column direction (y direction) in the matrix are connected in parallel. Between the wiring 103 for supplying a current from the power source, the intersection of the wiring 102 and the wiring 103, and each of the plurality of magnetic thin wires 101. In which includes a transistor 104 which can switch the current on / off for moving the domain walls flowing in each magnetic thin wire.

  According to the above configuration, the aggregate 110 of the magnetic thin wires 101 is connected in parallel to the power supply by the wiring 103. Therefore, according to the magnetic memory 400 of the present embodiment, the resistance value due to the magnetic wire can be reduced as compared with the conventional MRTM, so that the power consumption can be reduced.

  Further, according to the above configuration, since the transistor 104 is provided in each aggregate 110, the domain walls of the magnetic wires 101 included in the arbitrary aggregate 110 can be individually moved. Thereby, the random access property of the magnetic memory 400 is improved as compared with the conventional MRTM.

  Furthermore, information can be recorded or reproduced using the method described in Embodiment 1 by controlling the direction of the current flowing through the magnetic wire 101 belonging to the desired aggregate 110 and moving the domain wall.

  In particular, according to the magnetic memory 400 of this embodiment, the transistor 104 is provided for each aggregate 110 of magnetic wires in which at least two or more magnetic wires 101 are connected in series. Accordingly, the number of transistors 104 can be reduced, and cost reduction can be realized.

  In the magnetic memory 400 of this embodiment, for example, the wirings 103 provided at both ends of the aggregate 110a connect the aggregate 110a and the aggregate 110d adjacent in the row direction (x direction) of the matrix to the power source. Different from the wiring 103.

  According to the above configuration, each of the aggregates 110 a and 110 d adjacent to each other in the row direction (x direction) of the matrix is independently connected to the power source by the different wiring 103. Thereby, the magnetic memory 400 of this embodiment sets the current direction of the aggregate 110 in one operation by energizing all the wirings 103 at the same time, and moves the domain walls of many magnetic thin wires 101. The driving speed can be further increased.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. Embodiments are also included in the technical scope of the present invention.

  The present invention can also be expressed as follows. That is, in the magnetic memory of the present invention, a unit cell is composed of a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing on the magnetic thin wire, and the magnetic thin wire in the unit cell is electrically connected. A memory chip having a plurality of magnetic wire lines connected in series is connected to a magnetic section recorded on the magnetic wire by a power source that supplies current to the magnetic wires connected in series when recording or reproducing magnetic information. A magnetic memory for recording / reproducing magnetic information by moving a magnetic domain wall formed by an electric current, wherein the desired unit cell or the cell formed by dividing a series of magnetic wire lines connected in series By providing means for supplying a current only to the magnetic thin wires of the aggregate, it may be configured such that only the desired domain walls in the magnetic thin wires can be moved.

  In the magnetic memory of the present invention, a unit cell is composed of a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing on the magnetic thin wire, and the magnetic thin wire in the unit cell is electrically connected. A memory chip having a plurality of recording medium units connected in series is connected to a magnetic section recorded on the magnetic thin line by a power source that supplies current to the magnetic thin line connected in series at the time of recording or reproducing magnetic information. A magnetic memory that records and reproduces magnetic information by moving a magnetic domain wall formed by an electric current, and is connected in series by providing wiring at both ends of the magnetic thin wire in the cell and supplying current from the wiring. It may be configured to be able to move only the magnetic wall of the specific magnetic wire in the magnetic wire array.

  Furthermore, the wirings provided at both ends of the magnetic thin wires in the unit cell may be shared between the unit cells.

  In the magnetic memory of the present invention, a unit cell is composed of a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing on the magnetic thin wire, and the magnetic thin wire in the unit cell is electrically connected. A memory chip having a plurality of recording medium units connected in series is connected to a magnetic section recorded on the magnetic thin line by a power source that supplies current to the magnetic thin line connected in series at the time of recording or reproducing magnetic information. A magnetic memory that records and reproduces magnetic information by moving a magnetic domain wall formed by an electric current, and wiring is provided at both ends of the cell assembly formed by dividing the magnetic wire array connected in series. Even if the current is supplied from the wiring, it is possible to move only the magnetic walls of the magnetic wires of the specific assembly in the magnetic wire arrays connected in series. There.

  Furthermore, the wiring provided at both ends of the unit cell assembly may be shared between the unit cell assemblies.

  In the magnetic memory of the present invention, a unit cell is composed of a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing on the magnetic thin wire, and the magnetic thin wire in the unit cell is electrically connected. A memory chip having a plurality of recording medium units connected to each other, and a magnetic wall formed in the magnetic section recorded on the magnetic thin wire is supplied with current by a power source that supplies current to the magnetic thin wire when recording or reproducing magnetic information. It is possible to use a magnetic memory that records and reproduces magnetic information by moving the unit cells, and the unit cells are wired in parallel.

  In the magnetic memory of the present invention, a unit cell is composed of a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing on the magnetic thin wire, and the magnetic thin wire in the unit cell is electrically connected. A memory chip having a plurality of recording medium units connected to each other, and a magnetic wall formed in the magnetic section recorded on the magnetic thin wire is supplied with current by a power source that supplies current to the magnetic thin wire when recording or reproducing magnetic information. It is also possible to use a magnetic memory that records and reproduces magnetic information by moving a group of unit cells connected in series with at least two or more unit cells connected in series.

  Furthermore, a switching element may be arranged at one end of the unit cell. Further, in order to supply a current to the magnetic thin wire in the unit cell, each wiring may be provided with a drive circuit to set the direction of the flowing current.

  The wiring method of the magnetic memory according to the present invention includes a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing data on the magnetic thin wire, and the magnetic cell in the unit cell. A memory chip having a plurality of recording medium units electrically connected in series with thin wires, and recorded on the magnetic wires by a power source that supplies current to the magnetic wires connected in series when recording or reproducing magnetic information A magnetic memory wiring method for recording / reproducing magnetic information by moving a domain wall formed in a magnetic section by an electric current, wherein the unit cell or the magnetic wire array connected in series is divided. A switching element is arranged at one end of the cell assembly, wiring is provided at both ends of the unit cell or the unit cell assembly, and a current is supplied to the magnetic thin wire at the wiring end. Or a method of connecting to the dynamic circuit.

  The wiring method of the magnetic memory according to the present invention includes a magnetic thin wire as a recording medium and a recording / reproducing element for recording / reproducing data on the magnetic thin wire, and the magnetic cell in the unit cell. A memory chip having a plurality of recording medium units to which fine wires are electrically connected is formed in a magnetic section recorded on the magnetic thin wires by a power source that supplies current to the magnetic fine wires when recording or reproducing magnetic information. A magnetic memory wiring method for moving a domain wall by an electric current to record / reproduce magnetic information, wherein the unit cell or a group of unit cells in which at least two unit cells are connected in series A method in which a switching element is arranged at one end, the unit cell or the assembly of unit cells is connected in parallel, and the wiring end is connected to a drive circuit for supplying current to the magnetic wire It may be.

  The magnetic memory driving method of the present invention comprises a magnetic cell as a recording medium and a recording / reproducing element for recording / reproducing data on the magnetic wire, and the magnetic cell in the unit cell. A switching element at one end of the unit cell or a group of cells formed by dividing the magnetic thin wire array connected in series is a memory chip having a plurality of recording medium units in which the thin wires are electrically connected in series A magnetic memory driving method in which wiring is provided at both ends of the unit cell or the assembly of unit cells, and the wiring end is connected to a driving circuit for supplying current to the magnetic wire, The end of the wiring is connected to the positive potential of the power source by the on / off of the switching element arranged at one end of the unit cell or the unit cell assembly and the drive circuit, By switching between the connection to the land potential or the open state, the voltage applied between the wirings is appropriately combined to control the current flowing through the desired unit cell or group of unit cells. A method of moving the domain wall in the corresponding magnetic wire may be used.

  The magnetic memory driving method of the present invention comprises a magnetic cell as a recording medium and a recording / reproducing element for recording / reproducing data on the magnetic wire, and the magnetic cell in the unit cell. A memory chip having a plurality of recording medium units electrically connected with thin wires, and a switching element is arranged at one end of the unit cell or a group of unit cells in which at least two or more unit cells are connected in series A method of driving a magnetic memory, wherein the unit cell or the assembly of unit cells is connected in parallel, and a wiring end is connected to a drive circuit for supplying a current to a magnetic wire. Alternatively, the end of the wiring is connected to the positive potential of the power source by turning on / off the switching element disposed at one end of the unit cell assembly and the driving circuit, or By switching between connecting to the potential or opening, the voltage applied between the wirings is appropriately combined, and the current flowing in the desired unit cell or the assembly of unit cells is controlled, A method of moving the domain wall in the corresponding magnetic wire may be used.

  According to the present invention, it is possible to provide a magnetic memory that is excellent in random accessibility and can realize low power consumption. In particular, the present invention is suitable for improving the random accessibility of MRTM, which is expected to be applied as a universal memory, and reducing power consumption.

It is a figure which shows the structure of the principal part of the magnetic memory which concerns on one Embodiment of this invention. It is a figure which shows the magnetic memory of FIG. 1 with a drive circuit. FIG. 3 is a cross-sectional view taken along line A-A ′ in the magnetic memory of FIG. 2. It is a figure which shows the structure of the principal part of the magnetic memory which concerns on other embodiment of this invention. It is a figure which shows the magnetic memory of FIG. 4 with a drive circuit. FIG. 6 is a cross-sectional view taken along line A-A ′ in the magnetic memory of FIG. 5. It is a figure which shows the structure of the principal part of the magnetic memory which concerns on further another embodiment of this invention. It is a figure which shows the magnetic memory of FIG. 7 with a drive circuit. It is a figure which shows the structure of the unit cell of MRTM described in patent document 1 and 2. FIG. It is a figure which shows the structure of the principal part of the conventional magnetic memory. It is a figure for demonstrating the recording / reproducing method of a magnetic memory. It is a figure which shows the cell array of MRAM.

Explanation of symbols

100, 200, 300, 400 Magnetic memory 101, 101a to 101f Magnetic thin wire 102 Wiring (series connection wiring)
103 wiring (parallel connection wiring)
104 Transistor (switching element)
108 drive circuit 110, 110a-110f aggregate

Claims (11)

A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory that records or reproduces information by moving a domain wall that partitions magnetic domains by a current supplied from a power source,
A plurality of magnetic fine wires adjacent in the column direction in the matrix are connected in parallel, and parallel connection wiring for supplying current from the power source;
Switching that can switch on / off of the current that moves the domain wall flowing in each of the magnetic thin wires between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of magnetic thin wires And a magnetic memory.   The parallel connection wiring provided in an arbitrary magnetic thin wire in the plurality of magnetic thin wires is the same as the parallel connection wiring provided in the magnetic thin wire adjacent to the magnetic thin wire in the row direction of the matrix. Item 2. The magnetic memory according to Item 1.   2. The parallel connection wiring provided in an arbitrary magnetic thin wire in the plurality of magnetic thin wires is different from the parallel connection wiring provided in the magnetic thin wire adjacent to the magnetic thin wire in the row direction of the matrix. The magnetic memory described in 1. A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory that records or reproduces information by moving a domain wall that partitions magnetic domains by a current supplied from a power source,
When the plurality of magnetic thin wires connected in series are regarded as one aggregate, a plurality of aggregates adjacent in the column direction in the matrix are connected in parallel to supply current from the power source. Parallel connection wiring,
Switching that can switch on / off of the current that moves the domain wall flowing in each of the magnetic thin wires between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of aggregates And a magnetic memory.   The parallel connection wiring provided in an arbitrary aggregate in the plurality of aggregates is the same as the parallel connection wiring provided in the aggregate adjacent to the aggregate in the row direction of the matrix. Item 5. The magnetic memory according to Item 4.   5. The parallel connection wiring provided in an arbitrary aggregate in the plurality of aggregates is different from the parallel connection wiring provided in an aggregate adjacent to the aggregate in the row direction of the matrix. The magnetic memory described in 1. A drive circuit for a magnetic memory according to any one of claims 1 to 6,
A drive circuit characterized in that the direction of a current supplied from the power source to the magnetic wire can be changed. A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory wiring method for recording or reproducing information by moving a domain wall that partitions magnetic domains by a current supplied from a power source,
A plurality of magnetic thin wires adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring, and current is supplied from the power source to the magnetic thin wire through the parallel connection wiring.
A switching element is provided between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of magnetic thin wires, and the switching element turns on the current that moves the domain wall flowing in each of the magnetic thin wires. A method of wiring a magnetic memory, characterized in that switching is turned off / off. A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory wiring method for recording or reproducing information by moving a domain wall that partitions magnetic domains by a current supplied from a power source,
When the plurality of magnetic thin wires connected in series are regarded as one aggregate, a plurality of aggregates adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring, and the power supply Supply current to the magnetic wire through parallel connection wiring,
A switching element is provided between the intersection of the series connection wiring and the parallel connection wiring, and each of the plurality of aggregates, and the switching element turns on the current that moves the magnetic domain wall that flows to each of the magnetic wires. A method of wiring a magnetic memory, characterized in that switching is turned off / off. A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory driving method for recording or reproducing information by moving a domain wall that partitions magnetic domains by a current supplied from a power source via a driving circuit,
In the magnetic memory, a plurality of magnetic thin wires adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring, and current is supplied from the power source to the magnetic thin wire through the parallel connection wiring. Yes,
A switching element is provided between the intersection of the series connection wiring and the parallel connection wiring and each of the plurality of magnetic thin wires, and the switching element turns on the current that moves the domain wall flowing in each of the magnetic thin wires. A method for driving a magnetic memory, wherein the magnetic memory is driven by switching between / off and further switching a direction of a current for moving the domain wall by the drive circuit. A plurality of magnetic thin wires that are adjacent to each other in the row direction of the matrix are connected in series by a serial connection wiring, and a plurality of magnetic thin wires formed in each of the plurality of magnetic thin wires A magnetic memory driving method for recording or reproducing information by moving a domain wall that partitions magnetic domains by a current supplied from a power source via a driving circuit,
In the magnetic memory, when the plurality of magnetic thin wires connected in series are regarded as one aggregate, a plurality of aggregates adjacent in the column direction in the matrix are connected in parallel by parallel connection wiring. , Supplying current from the power source to the magnetic wire through the parallel connection wiring,
A switching element is provided between the intersection of the series connection wiring and the parallel connection wiring, and each of the plurality of aggregates, and the switching element turns on the current that moves the magnetic domain wall that flows to each of the magnetic wires. A method for driving a magnetic memory, wherein the magnetic memory is driven by switching between / off and further switching a direction of a current for moving the domain wall by the drive circuit.

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