JP5472832B2 - Magnetic memory - Google Patents

Description

  The present invention relates to a spin transfer type magnetic memory.

  In recent years, there has been an increasing demand for the development of high-speed and large-capacity nonvolatile memories. For example, in a small information device such as a portable terminal, if a non-volatile memory that can serve as both a high-speed work memory and a large-capacity storage memory is realized, power consumption and waste of a memory area can be eliminated. In addition, if a high-speed and large-capacity nonvolatile memory is realized, an “instant-on” function that can instantly start the device after the power is turned on becomes possible.

  One promising nonvolatile memory from the viewpoint of large capacity and high-speed operation is a magnetic random access memory (MRAM). In the MRAM, a “magnetoresistance element” whose resistance value changes due to the magnetoresistance effect is used as a memory cell. More specifically, the magnetoresistive element is sandwiched between a magnetization fixed layer whose magnetization direction is fixed, a magnetic recording layer (magnetization free layer) whose magnetization direction can be reversed, and the magnetization fixed layer and the magnetic recording layer. It is comprised from a nonmagnetic layer. The resistance value (R + ΔR) when the magnetization directions of the magnetization fixed layer and the magnetic recording layer are “antiparallel” is larger than the resistance value (R) when they are “parallel” due to the magnetoresistance effect. The memory cell of the MRAM stores data in a nonvolatile manner by utilizing such a change in resistance value.

As a magnetoresistive element, a GMR element using a giant magnetoresistive (GMR) effect and an MTJ (MTJ: magneto tunnel junction) element using a tunnel magnetoresistive (TMR) effect are known. . In the case of an MTJ element, an insulating layer (tunnel barrier layer) such as MgO or Al ₂ O ₃ is used as a nonmagnetic layer sandwiched between a magnetization fixed layer and a magnetic recording layer. In general, the MR ratio (= ΔR / R) of the MTJ element is larger than that of the GMR element. Furthermore, the resistance value of the MTJ element is higher than that of the GMR element, and can be adjusted to a value equivalent to the on resistance of the transistors connected in series. These are preferable from the viewpoint of the data read signal, and it is preferable to use the MTJ element as a memory cell of the MRAM.

  Data writing is performed by reversing the magnetization direction of the magnetic recording layer. A typical data writing method is a “current magnetic field method”. According to the current magnetic field method, a write current is caused to flow through the write wiring arranged in the vicinity of the magnetoresistive element. Then, a write magnetic field generated by the write current is applied to the magnetic recording layer, thereby reversing the magnetization direction of the magnetic recording layer. According to this current magnetic field method, the reversal magnetic field required for reversal of the magnetization direction of the magnetic recording layer becomes large in inverse proportion to the size of the magnetoresistive element. That is, there is a problem that the write current increases as the memory cell is miniaturized.

As a write method that can suppress an increase in write current due to miniaturization, “spin transfer (spin
"transfer" method has been proposed (see Non-Patent Document 1, for example). According to the spin transfer method, a spin-polarized current is injected into the ferromagnetic conductor, and the magnetization direction is reversed by a direct interaction between the spin of the conduction electron carrying the current and the magnetic moment of the conductor. To do. Such magnetization reversal is also referred to as “Spin Transfer Magnetization Switching”. An outline of spin injection magnetization reversal will be described with reference to FIG.

  FIG. 1 shows a configuration of a typical memory cell 100 (two-terminal MTJ element). The memory cell 100 includes a first terminal T101, a second terminal T102, a magnetization fixed layer 110, a tunnel barrier layer 120, and a magnetic recording layer (magnetization free layer) 130. The tunnel barrier layer 120 is sandwiched between the magnetization fixed layer 110 and the magnetic recording layer 130, and a magnetic tunnel junction (MTJ) is formed by the magnetization fixed layer 110, the tunnel barrier layer 120, and the magnetic recording layer 130. Yes. Further, the first terminal T101 is connected to the magnetization fixed layer 110, and the second terminal T102 is connected to the magnetic recording layer 130. In other words, the first terminal T101 and the second terminal T102 are connected to both ends of the MTJ. The two-terminal MTJ element configured as described above is used as the memory cell 100.

  In this memory cell 100, a low resistance state in which the magnetization directions of the magnetization fixed layer 110 and the magnetic recording layer 130 are “parallel” is associated with data “0”, and a high resistance state in which they are “antiparallel” is data. Corresponds to “1”. At the time of data reading, a moderately large read current is passed between the first terminal T101 and the second terminal T102 so as to penetrate the MTJ. Based on the read current, it is possible to determine the magnitude of the resistance value, that is, whether the recording data is “1” or “0”.

  At the time of data writing, a write current is passed between the first terminal T101 and the second terminal T102 so as to penetrate the MTJ. Specifically, at the time of transition from data “1” to data “0”, the write current flows from the second terminal T102 to the first terminal T101. In this case, electrons having the same spin state as the magnetization fixed layer 110 serving as a spin filter move from the magnetization fixed layer 110 to the magnetic recording layer 130 through the tunnel barrier layer 120. Due to the spin transfer effect, the magnetization direction of the magnetic recording layer 130 is reversed and becomes “parallel” to the magnetization direction of the magnetization fixed layer 110. On the other hand, at the time of transition from data “0” to data “1”, the write current flows from the first terminal T101 to the second terminal T102. In this case, electrons having the same spin state as the magnetization fixed layer 110 as a spin filter move from the magnetic recording layer 130 to the magnetization fixed layer 110 through the tunnel barrier layer 120. Due to the spin transfer effect, the magnetization direction of the magnetic recording layer 130 is reversed and becomes “antiparallel” to the magnetization direction of the magnetization fixed layer 110.

  Thus, in the spin transfer method, data writing is performed by the movement of spin electrons. The magnetization direction of the magnetic recording layer 130 can be defined according to the direction of the write current (spin polarization current) injected perpendicular to the film surface. Here, it is known that the threshold value of the spin injection magnetization reversal depends on the current density of the spin-polarized current. Therefore, as the memory cell size is reduced, the write current required for spin injection magnetization reversal decreases. Since the write current decreases with the miniaturization of the memory cell, the spin transfer method is important for realizing a large capacity of the MRAM.

  However, in the case of the configuration shown in FIG. 1, the read current path and the write current path are the same. That is, not only the read current but also a large write current flows through the MTJ. This causes the following problems.

  First, at the time of data writing, a high voltage for flowing a write current is applied to the tunnel barrier layer 120. The application of such a high voltage causes dielectric breakdown in the tunnel barrier layer 120 that is an insulating layer. The memory cell 100 in which the dielectric breakdown has occurred no longer functions normally and becomes a defective cell. This reduces the reliability of the memory.

  In order to reduce the voltage applied to the tunnel barrier layer 120, it is conceivable to lower the resistance value of the tunnel barrier layer 120. However, when the resistance value of the tunnel barrier layer 120 becomes small, the balance with the on-resistance of the transistors connected in series to the MTJ is lost, which causes a reduction in the amount of data read signals. Further, when the thickness of the tunnel barrier layer 120 is reduced in order to reduce the resistance value, defects such as pinholes increase, and dielectric breakdown is more likely to occur. These things ultimately reduce the reliability of the memory.

  Further, according to Non-Patent Document 2 and Non-Patent Document 3, in order to reduce the pulse width of the write current while realizing the spin injection magnetization reversal, it is necessary to increase the write current amount. That is, it is necessary to further increase the write current in order to increase the write speed and realize a high-speed operation. In this case, dielectric breakdown tends to occur, and the reliability of the memory decreases.

  As described above, when the write current passes through the MTJ, the dielectric breakdown is likely to occur in the tunnel barrier layer 120, which causes a decrease in memory reliability.

  As a related technique, Patent Document 1 (Japanese Patent Laid-Open No. 2005-50907) discloses a magnetoresistive element based on a spin transfer method. The magnetoresistive element includes a first magnetization fixed layer, a second magnetization fixed layer, a magnetic recording layer provided between the first magnetization fixed layer and the second magnetization fixed layer, a first magnetization fixed layer, and a magnetic A tunnel barrier layer provided between the recording layer and an intermediate layer provided between the magnetic recording layer and the second magnetization pinned layer. The magnetization directions of the first magnetization pinned layer and the second magnetization pinned layer are opposite to each other. In this magnetoresistive element, spin transfer occurs from both the first magnetization fixed layer and the second magnetization fixed layer to the magnetic recording layer. Thereby, the write current is reduced. However, the read current path and the write current path are the same, and the write current does not change through the tunnel barrier layer.

Japanese Patent Laying-Open No. 2005-50907

J. C. Slonczewski, "Current-drivenexcitation of magnetic multilayers", Journal of Magnetism and MagneticMaterials, 159, 1996, L1-L7. R. H. Koch et al., "Time-ResolvedReversal of Spin-Transfer Switching in a Nanomagnet", Physical Review Letters, 92, 2004, 088302. R. Heindl et al., "Size dependence of intrinsic spin transfer switching current density in elliptical spinvalues", Applied Physics Letters, 92, 2008, 262504.

  As described above, in the case of the spin transfer method shown in FIG. 1, the read current path and the write current path are the same, and the write current passes through the tunnel barrier layer (MTJ). In this case, dielectric breakdown is likely to occur in the tunnel barrier layer, which causes a decrease in reliability.

  One object of the present invention is to provide a spin transfer type magnetic memory capable of preventing dielectric breakdown in a tunnel barrier layer.

  In one aspect of the present invention, a spin transfer type magnetic memory including a plurality of memory cells is provided. Each of the plurality of memory cells is sandwiched between a magnetic recording layer including a ferromagnetic layer whose magnetization direction can be reversed, a sense layer including a ferromagnetic layer having a fixed magnetization direction, and the magnetic recording layer and the sense layer. A tunnel barrier layer, a first spin supply layer including a ferromagnetic layer with a fixed magnetization direction, a first nonmagnetic layer sandwiched between the magnetic recording layer and the first spin supply layer, A terminal, a second terminal, and a third terminal. The first terminal is connected to the magnetic recording layer via the sense layer and the tunnel barrier layer. The second terminal is connected to the magnetic recording layer via the first spin supply layer and the first nonmagnetic layer. The third terminal is connected to the magnetic recording layer without passing through the sense layer, tunnel barrier layer, first spin supply layer, and first nonmagnetic layer.

  In another aspect of the present invention, a semiconductor integrated circuit is provided. The semiconductor integrated circuit includes a spin transfer type first magnetic memory including a plurality of first memory cells and a spin transfer type second magnetic memory including a plurality of second memory cells.

  Each of the plurality of first memory cells includes a first magnetic recording layer including a ferromagnetic layer whose magnetization direction can be reversed, a first sense layer including a ferromagnetic layer whose magnetization direction is fixed, and a first magnetic recording layer A first tunnel barrier layer sandwiched between the first and second sense layers, a first spin supply layer including a ferromagnetic layer having a fixed magnetization direction, a first magnetic recording layer, and a first spin supply layer A first nonmagnetic layer, a first terminal, a second terminal, and a third terminal sandwiched therebetween are provided. The first terminal is connected to the first magnetic recording layer via the first sense layer and the first tunnel barrier layer. The second terminal is connected to the first magnetic recording layer via the first spin supply layer and the first nonmagnetic layer. The third terminal is connected to the first magnetic recording layer without passing through the first sense layer, the first tunnel barrier layer, the first spin supply layer, and the first nonmagnetic layer.

  Each of the plurality of second memory cells includes a second magnetic recording layer including a ferromagnetic layer whose magnetization direction can be reversed, a second sense layer including a ferromagnetic layer having a fixed magnetization direction, and a second magnetic recording layer And a second tunnel barrier layer sandwiched between the second sense layer, a fourth terminal connected to the second sense layer, and a fifth terminal connected to the second magnetic recording layer. .

  The spin transfer magnetic memory according to the present invention can prevent dielectric breakdown in the tunnel barrier layer. As a result, the reliability of the memory is improved.

  The above and other objects, advantages, and features will become apparent from the embodiments of the present invention described in conjunction with the following drawings.

FIG. 1 schematically shows the configuration of a typical MRAM memory cell. FIG. 2 schematically shows a configuration of the MRAM according to the embodiment of the present invention. FIG. 3 schematically shows the configuration of the memory cell of the MRAM according to the embodiment of the present invention. FIG. 4 shows a path of a read current in the memory cell shown in FIG. FIG. 5 shows a path of a write current in the memory cell shown in FIG. FIG. 6 is a cross-sectional view showing the configuration of the memory cell according to the first embodiment. FIG. 7 is a plan view showing a cell layout in the first embodiment. FIG. 8 is a circuit diagram showing a configuration of the memory cell according to the first embodiment. FIG. 9 is a cross-sectional view showing the configuration of the memory cell according to the second embodiment. FIG. 10 is a plan view showing a cell layout in the second embodiment. FIG. 11 is a circuit diagram showing a configuration of a memory cell according to the second embodiment. FIG. 12 is a cross-sectional view showing the configuration of the memory cell according to the third embodiment. FIG. 13 is a cross-sectional view showing the configuration of the memory cell according to the fourth embodiment. FIG. 14 is a cross-sectional view showing the configuration of the memory cell according to the fifth embodiment. FIG. 15 is a cross-sectional view showing the configuration of the memory cell according to the sixth embodiment. FIG. 16 schematically shows a configuration of a semiconductor chip according to the seventh embodiment. FIG. 17 is a cross-sectional view showing the configuration of the memory cell according to the seventh embodiment.

  Embodiments of the present invention will be described with reference to the accompanying drawings.

  In an embodiment of the present invention, a spin transfer magnetic memory is provided. Hereinafter, a spin transfer type MRAM will be described as an example. FIG. 2 schematically shows the configuration of the MRAM according to the present embodiment. As shown in FIG. 2, the MRAM includes a plurality of memory cells 1 arranged in an array.

  FIG. 3 shows a configuration of the memory cell 1 (three-terminal MTJ element) according to the present embodiment. The memory cell 1 includes a first terminal T1, a second terminal T2, a third terminal T3, a sense layer (first magnetization fixed layer) 10, a tunnel barrier layer 20, a magnetic recording layer (magnetization free layer) 30, and a nonmagnetic layer 40. , And a spin supply layer (second magnetization fixed layer) 50.

  The sense layer (first magnetization fixed layer) 10 includes a ferromagnetic layer whose magnetization direction is fixed. The sense layer 10 may have a laminated ferrimagnetic structure in which a plurality of ferromagnetic layers are laminated via a nonmagnetic layer. Also in that case, the magnetization directions of the plurality of ferromagnetic layers are fixed. One of the ferromagnetic layers included in the sense layer 10 is in contact with the tunnel barrier layer 20. In the following description, the magnetization direction of the sense layer 10 means the magnetization direction of the ferromagnetic layer in contact with the tunnel barrier layer 20.

The tunnel barrier layer 20 is an insulating layer sandwiched between the sense layer 10 and the magnetic recording layer 30. The tunnel barrier layer 20 is formed of an insulating material such as MgO or Al ₂ O ₃ .

  The nonmagnetic layer 40 is sandwiched between the spin supply layer 50 and the magnetic recording layer 30. The nonmagnetic layer 40 is formed of a nonmagnetic conductive material such as Ru or Cu, for example.

  The spin supply layer (second magnetization fixed layer) 50 includes a ferromagnetic layer whose magnetization direction is fixed. The spin supply layer 50 may have a laminated ferrimagnetic structure in which a plurality of ferromagnetic layers are laminated via a nonmagnetic layer. Also in that case, the magnetization directions of the plurality of ferromagnetic layers are fixed. One of the ferromagnetic layers included in the spin supply layer 50 is in contact with the nonmagnetic layer 40. In the following description, the magnetization direction of the spin supply layer 50 means the magnetization direction of the ferromagnetic layer in contact with the nonmagnetic layer 40. The spin supply layer 50 is physically separated from the sense layer 10. The magnetization direction of the spin supply layer 50 is parallel or antiparallel to the magnetization direction of the sense layer 10.

  The magnetic recording layer (magnetization free layer) 30 includes a ferromagnetic layer whose magnetization direction can be reversed. The magnetization direction of the magnetic recording layer 30 is allowed to be “parallel” or “antiparallel” with the magnetization direction of the sense layer 10. In addition, the magnetization direction of the magnetic recording layer 30 is allowed to be “parallel” or “anti-parallel” with the magnetization direction of the spin supply layer 50.

  The magnetic recording layer 30 is connected to the sense layer 10 through the tunnel barrier layer 20. That is, the MTJ is formed by the sense layer 10, the tunnel barrier layer 20, and the magnetic recording layer 30. The portion including the MTJ is hereinafter referred to as “MTJ portion SR”. The MTJ portion SR includes at least the sense layer 10, the tunnel barrier layer 20, and the magnetic recording layer 30. The MTJ portion SR may include a nonmagnetic layer 40 and a spin supply layer 50. As will be described later, a read current Ir flows in the MTJ portion SR when reading data. Conversely, the portion through which the read current Ir flows can also be defined as the MTJ portion SR.

  The magnetic recording layer 30 is connected to the spin supply layer 50 through the nonmagnetic layer 40. The magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50 form a “spin transfer portion SW”. It should be noted that the spin transfer unit SW includes the magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50, but does not include the sense layer 10 and the tunnel barrier layer 20. As will be described later, a write current Iw flows through the spin transfer unit SW during data writing. Conversely, the portion through which the write current Iw flows can also be defined as the spin transfer unit SW.

  The first terminal T1 is connected to one end of the MTJ portion SR. More specifically, as shown in FIG. 3, the first terminal T1 is connected to the sense layer 10 of the MTJ portion SR. That is, the first terminal T1 is connected to the magnetic recording layer 30 via the sense layer 10 and the tunnel barrier layer 20.

  The second terminal T2 is connected to one end of the spin transfer unit SW. More specifically, as shown in FIG. 3, the second terminal T2 is connected to the spin supply layer 50 of the spin transfer unit SW. That is, the second terminal T2 is connected to the magnetic recording layer 30 through the spin supply layer 50 and the nonmagnetic layer 40.

  The third terminal T3 is connected to the other end of the spin transfer unit SW. More specifically, as shown in FIG. 3, the third terminal T <b> 3 is connected to the magnetic recording layer 30. Here, it should be noted that the third terminal T3 is connected to the magnetic recording layer 30 without the sense layer 10, the tunnel barrier layer 20, the nonmagnetic layer 40, and the spin supply layer 50 described above. This means that by using the second terminal T2 and the third terminal T3, a current that passes through the spin transfer unit SW but does not pass through the tunnel barrier layer 20 can flow.

  FIG. 4 shows the path PR of the read current Ir at the time of data reading. The read current Ir flows between the first terminal T1 and the second terminal T2 or between the first terminal T1 and the third terminal T3. In any case, the read current Ir flows between the sense layer 10 (first magnetization fixed layer) and the magnetic recording layer 30 through the tunnel barrier layer 20. When the magnetization directions of the sense layer 10 and the magnetic recording layer 30 are “parallel”, the resistance value of the MTJ portion SR is relatively low, and the low resistance state is associated with data “0”. On the other hand, when the magnetization directions of the sense layer 10 and the magnetic recording layer 30 are “antiparallel”, the resistance value of the MTJ portion SR is relatively high, and the high resistance state is associated with data “1”. Based on the read current Ir shown in FIG. 4, the magnitude of the resistance value, that is, whether the recording data is “1” or “0” can be determined.

  FIG. 5 shows a path PW of the write current Iw at the time of data writing. The write current Iw is passed between the second terminal T2 and the third terminal T3. That is, the write current Iw flows between the spin supply layer 50 and the magnetic recording layer 30 through the nonmagnetic layer 40. At this time, the spin supply layer 50 whose magnetization direction is fixed serves as a spin filter, and spin transfer occurs between the spin supply layer 50 and the magnetic recording layer 30.

  For example, as shown in FIG. 5, consider a case where the magnetization directions of the sense layer 10 and the spin supply layer 50 are opposite to each other. In the data “0” state, the magnetization direction of the magnetic recording layer 30 is “parallel” to the magnetization direction of the sense layer 10 and “anti-parallel” to the magnetization direction of the spin supply layer 50. On the other hand, in the data “1” state, the magnetization direction of the magnetic recording layer 30 is “antiparallel” to the magnetization direction of the sense layer 10 and “parallel” to the magnetization direction of the spin supply layer 50. At the time of transition from data “0” to data “1”, the write current Iw flows from the third terminal T3 to the second terminal T2. In this case, electrons having the same spin state as the spin supply layer 50 move from the spin supply layer 50 to the magnetic recording layer 30 through the nonmagnetic layer 40. Due to the spin transfer effect, the magnetization direction of the magnetic recording layer 30 is reversed and becomes “parallel” to the magnetization direction of the spin supply layer 50. On the other hand, at the time of transition from data “1” to data “0”, the write current flows from the second terminal T2 to the third terminal T3. In this case, electrons having the same spin state as the spin supply layer 50 move from the magnetic recording layer 30 to the spin supply layer 50 through the nonmagnetic layer 40. Due to the spin transfer effect, the magnetization direction of the magnetic recording layer 30 is reversed and becomes “antiparallel” to the magnetization direction of the spin supply layer 50. Thus, the magnetization direction of the magnetic recording layer 30 can be defined according to the direction of the write current Iw.

  As described above, according to the present embodiment, data is written by the spin transfer method. In the case of the spin transfer method, the write current Iw can be further reduced as the memory cell is miniaturized. This is preferable from the viewpoint of increasing the capacity of the MRAM and reducing the power consumption.

  In the present embodiment, as is clear from FIG. 5, the write current Iw does not penetrate the tunnel barrier layer 20. The write current path PW (spin transfer unit SW) between the second terminal T2 and the third terminal T3 includes the magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50. The barrier layer 20 is not included. Therefore, by using the second terminal T2 and the third terminal T3, the write current Iw that passes through the spin transfer unit SW but does not pass through the tunnel barrier layer 20 can be passed. Since the large write current Iw does not penetrate the tunnel barrier layer 20, the tunnel barrier layer 20 can be prevented from being deteriorated or broken down. As a result, the reliability of the MRAM is improved.

  Further, in the present embodiment, since the read current path PR and the write current path PW are different, it is possible to optimize the read characteristics and the write characteristics separately. For example, the read characteristics mainly depend on the MTJ including the tunnel barrier layer 20, but the tunnel barrier layer 20 is not included in the write current path PW. Therefore, the tunnel barrier layer 20 can be designed without being restricted from the viewpoint of data writing. As a result, the MR ratio of MTJ can be increased. It is also possible to adjust the MTJ resistance value to a value equivalent to the on resistance of the transistors connected in series. As a result, a sufficiently large read signal can be obtained when reading data.

  Furthermore, the pulse width of the write current Iw can be reduced in order to increase the write speed and realize high-speed operation. In this case, it is necessary to increase the amount of write current, but since the write current Iw does not penetrate the tunnel barrier layer 20, dielectric breakdown does not occur. That is, it is possible to improve the writing speed without causing dielectric breakdown or reliability deterioration.

  Note that a selection transistor may be provided in each of the read current path PR and the write current path PW. In this case, it is possible to suppress “sneak current” during data reading and data writing. The sneak current is a current that flows on a path parallel to the current path for the selected memory cell and does not pass through the selected memory cell. Since only the write target bit or the read target bit can be selectively operated, the array scale can be increased, and high-speed operation is also possible.

  Hereinafter, various embodiments will be described in detail.

1. First Embodiment FIG. 6 is a cross-sectional view showing a configuration of a memory cell 1 according to a first embodiment. FIG. 7 is a plan view showing a cell layout in the first embodiment. FIG. 8 is a circuit diagram showing a configuration of the memory cell 1 according to the first embodiment. A direction perpendicular to the surface of the semiconductor substrate 5 is defined as the Z direction, and a plane parallel to the surface is defined as the XY plane. The Z direction and the XY plane are orthogonal to each other.

  The memory cell 1 is formed on the semiconductor substrate 5. In the present embodiment, the sense layer 10, the tunnel barrier layer 20, the magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50 are stacked in this order from the semiconductor substrate 5 side. That is, the magnetic recording layer 30 is sandwiched between the tunnel barrier layer 20 and the nonmagnetic layer 40.

The sense layer 10, the magnetic recording layer 30, and the spin supply layer 50 are formed of an in-plane magnetization film having in-plane magnetic anisotropy or a perpendicular magnetization film having perpendicular magnetic anisotropy. In the example shown in FIG. 6, the sense layer 10, the magnetic recording layer 30, and the spin supply layer 50 are formed of in-plane magnetization films. The magnetization direction of the sense layer 10 is fixed in the −X direction, and the magnetization direction of the spin supply layer 50 is fixed in the + X direction. The magnetization direction of the magnetic recording layer 30 faces the + X direction or the −X direction. The tunnel barrier layer 20 is an insulating film such as an MgO film or an Al ₂ O ₃ film, for example. The nonmagnetic layer 40 is, for example, a nonmagnetic metal film such as a Ru film or a Cu film, or a low resistance oxide film.

  A magnetic recording layer 30 is formed on the upper surface of the sense layer 10 via a tunnel barrier layer 20. The bottom surface of the sense layer 10 is connected to a first contact part 60 formed on the semiconductor substrate 5. The first contact part 60 includes vias and wiring. The first contact portion 60 may include an underlayer and an antiferromagnetic layer for fixing the magnetization direction of the sense layer 10.

  A spin supply layer 50 is formed on the upper surface of the magnetic recording layer 30 with a nonmagnetic layer 40 interposed therebetween. More specifically, the top surface of the magnetic recording layer 30 has different first regions R1 and second regions R2. The nonmagnetic layer 40 and the spin supply layer 50 are formed on the first region R1. An upper connection portion 70 is formed on the spin supply layer 50. The upper connection portion 70 may include a cap layer and an antiferromagnetic layer for fixing the magnetization direction of the spin supply layer 50. The upper connection portion 70 is further connected to an upper wiring PL extending in the X direction. In the present embodiment, the upper connection portion 70 corresponds to the second terminal T2.

  A second contact portion 90 is formed on the semiconductor substrate 5. The second contact portion 90 includes a via and a wiring. Further, a nonmagnetic conductor layer 80 is formed so as to connect between the second contact portion 90 and the magnetic recording layer 30. The nonmagnetic conductor layer 80 is formed so as to be connected to the second region R2 on the upper surface of the magnetic recording layer 30, and is physically separated from the nonmagnetic layer 40 and the spin supply layer 50.

  The memory cell 1 further includes a first transistor TR1 and a second transistor TR2 formed on the semiconductor substrate 5. The gate electrode of the first transistor TR1 is connected to the first word line WL1 extending in the X direction. The gate electrode of the second transistor TR2 is connected to the second word line WL2 extending in the X direction.

  The first transistor TR1 is interposed between the first terminal T1 and the sense layer 10. More specifically, one of the source / drain of the first transistor TR1 is connected to the first terminal T1. The first terminal T1 is further connected to a first bit line BL1 extending in the Y direction. The other of the source / drain of the first transistor TR1 is connected to the sense layer 10 via the first contact portion 60.

  The second transistor TR2 is interposed between the third terminal T3 and the magnetic recording layer 30. More specifically, one of the source / drain of the second transistor TR2 is connected to the third terminal T3. The third terminal T3 is further connected to a second bit line BL2 extending in the Y direction. The other of the source / drain of the second transistor TR2 is connected to the second region R2 on the upper surface of the magnetic recording layer 30 via the second contact portion 90 and the nonmagnetic conductor layer 80.

  In the present embodiment, the MTJ portion SR includes a sense layer 10, a tunnel barrier layer 20, a magnetic recording layer 30, a nonmagnetic layer 40, and a spin supply layer 50. A read current path PR through which the read current Ir flows is between the first terminal T1 and the second terminal T2. A first transistor TR1 is provided as a selection transistor on the read current path PR. At the time of data reading, a high level voltage is applied to the first word line WL1, and the first transistor TR1 is turned on. On the other hand, a low level voltage is applied to the second word line WL2, and the second transistor TR2 is turned OFF. Further, a read voltage is applied between the first bit line BL1 and the upper wiring PL. As a result, the read current Ir flows through the read current path PR between the first terminal T1 and the second terminal T2.

  The spin transfer unit SW includes the magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50, but does not include the sense layer 10 and the tunnel barrier layer 20. A write current path PW through which the write current Iw flows is between the second terminal T2 and the third terminal T3. A second transistor TR2 is provided as a selection transistor on the write current path PW. At the time of data writing, a high level voltage is applied to the second word line WL2, and the second transistor TR2 is turned on. On the other hand, a low level voltage is applied to the first word line WL1, and the first transistor TR1 is turned off. Further, a write voltage is applied between the second bit line BL2 and the upper wiring PL. As a result, the write current Iw flows through the write current path PW between the second terminal T2 and the third terminal T3. The write current Iw does not penetrate the tunnel barrier layer 20.

In the case of the cell configuration according to the present embodiment, as shown in FIG. 7, the unit cell area per memory cell can be designed to be 16F ² (F: Feature Size: the minimum line width in lithography). .

2. Second Embodiment FIG. 9 is a cross-sectional view showing a configuration of a memory cell 1 according to a second embodiment. FIG. 10 is a plan view showing a cell layout in the second embodiment. FIG. 11 is a circuit diagram showing a configuration of the memory cell 1 according to the second embodiment. The description overlapping with the first embodiment is omitted as appropriate.

  In the present embodiment, the spin supply layer 50, the nonmagnetic layer 40, the magnetic recording layer 30, the tunnel barrier layer 20, and the sense layer 10 are stacked in this order from the semiconductor substrate 5 side. The magnetic recording layer 30 is sandwiched between the tunnel barrier layer 20 and the nonmagnetic layer 40.

  A magnetic recording layer 30 is formed on the upper surface of the spin supply layer 50 with a nonmagnetic layer 40 interposed therebetween. The bottom surface of the spin supply layer 50 is connected to a first contact part 60 formed on the semiconductor substrate 5. The first contact part 60 includes vias and wiring. The first contact portion 60 may include an underlayer and an antiferromagnetic layer for fixing the magnetization direction of the spin supply layer 50.

  A sense layer 10 is formed on the upper surface of the magnetic recording layer 30 via a tunnel barrier layer 20. More specifically, the top surface of the magnetic recording layer 30 has different first regions R1 and second regions R2. The tunnel barrier layer 20 and the sense layer 10 are formed on the first region R1. An upper connection portion 70 is formed on the sense layer 10. The upper connection portion 70 may include a cap layer and an antiferromagnetic layer for fixing the magnetization direction of the sense layer 10. The upper connection portion 70 is further connected to an upper wiring PL extending in the X direction. In the present embodiment, the upper connection portion 70 corresponds to the first terminal T1.

  A second contact portion 90 is formed on the semiconductor substrate 5. The second contact portion 90 includes a via and a wiring. Further, a nonmagnetic conductor layer 80 is formed so as to connect between the second contact portion 90 and the magnetic recording layer 30. The nonmagnetic conductor layer 80 is formed so as to be connected to the second region R2 on the upper surface of the magnetic recording layer 30, and is physically separated from the tunnel barrier layer 20 and the sense layer 10.

  The memory cell 1 further includes a first transistor TR1 and a second transistor TR2 formed on the semiconductor substrate 5. The gate electrodes of the first transistor TR1 and the second transistor TR2 are both connected to a common word line WL extending in the X direction.

  The first transistor TR1 is interposed between the second terminal T2 and the spin supply layer 50. More specifically, one of the source / drain of the first transistor TR1 is connected to the second terminal T2. The second terminal T2 is further connected to a first bit line BL1 extending in the Y direction. The other of the source / drain of the first transistor TR1 is connected to the spin supply layer 50 via the first contact portion 60.

  The second transistor TR2 is interposed between the third terminal T3 and the magnetic recording layer 30. More specifically, one of the source / drain of the second transistor TR2 is connected to the third terminal T3. The third terminal T3 is further connected to a second bit line BL2 extending in the Y direction. The other of the source / drain of the second transistor TR2 is connected to the second region R2 on the upper surface of the magnetic recording layer 30 via the second contact portion 90 and the nonmagnetic conductor layer 80.

  In the present embodiment, the MTJ portion SR includes a sense layer 10, a tunnel barrier layer 20, a magnetic recording layer 30, a nonmagnetic layer 40, and a spin supply layer 50. A read current path PR through which the read current Ir flows is between the first terminal T1 and the second terminal T2. A first transistor TR1 is provided as a selection transistor on the read current path PR. At the time of data reading, a high level voltage is applied to the word line WL, and the first transistor TR1 and the second transistor TR2 are turned on. The second bit line BL2 is set in a floating state (Hi-Z). Further, a read voltage is applied between the first bit line BL1 and the upper wiring PL. As a result, the read current Ir flows through the read current path PR between the first terminal T1 and the second terminal T2.

  The spin transfer unit SW includes the magnetic recording layer 30, the nonmagnetic layer 40, and the spin supply layer 50, but does not include the sense layer 10 and the tunnel barrier layer 20. A write current path PW through which the write current Iw flows is between the second terminal T2 and the third terminal T3. A first transistor TR1 and a second transistor TR2 are provided as selection transistors on the write current path PW. At the time of data writing, a high level voltage is applied to the word line WL, and the first transistor TR1 and the second transistor TR2 are turned on. The upper wiring 70 is set in a floating state (Hi-Z). Further, a write voltage is applied between the first bit line BL1 and the second bit line BL2. As a result, the write current Iw flows through the write current path PW between the second terminal T2 and the third terminal T3. The write current Iw does not penetrate the tunnel barrier layer 20.

As shown in FIG. 10, the first transistor TR1 and the second transistor TR2 share the word line WL. Further, contacts connected to the bit lines (BL1, BL2) are shared between adjacent cells. As a result, as shown in FIG. 10, the unit cell area per memory cell can be designed to be 12F ² (F: Feature Size: the minimum line width in lithography).

3. Third Embodiment FIG. 12 is a cross-sectional view showing a configuration of a memory cell 1 according to a third embodiment. The third embodiment is the same as the first embodiment described above except for the configuration of the magnetic recording layer 30. The description overlapping with the first embodiment is omitted as appropriate.

  In the present embodiment, the magnetic recording layer 30 includes a first magnetic recording layer 31, a second magnetic recording layer 32, and a nonmagnetic layer 33. The first magnetic recording layer 31 is a ferromagnetic layer whose magnetization direction can be reversed, and is in contact with the tunnel barrier layer 20. The second magnetic recording layer 32 is a ferromagnetic layer whose magnetization direction can be reversed, and is in contact with the nonmagnetic layer 40. The nonmagnetic layer 33 is sandwiched between the first magnetic recording layer 31 and the second magnetic recording layer 32. The nonmagnetic layer 33 is formed of a nonmagnetic conductive material such as Ru or Cu, for example.

  The first magnetic recording layer 31 and the second magnetic recording layer 32 are magnetically coupled to each other via the nonmagnetic layer 33. For example, the first magnetic recording layer 31 and the second magnetic recording layer 32 are antiferromagnetically coupled via the nonmagnetic layer 33. When the magnetization direction of the second magnetic recording layer 32 is reversed, the magnetization direction of the first magnetic recording layer 31 is also reversed accordingly.

  In FIG. 12, the upper surface of the first magnetic recording layer 31 has different first regions R1 and second regions R2. The second magnetic recording layer 32 is formed on the first region R1 via the nonmagnetic layer 33. A nonmagnetic layer 40 and a spin supply layer 50 are stacked on the second magnetic recording layer 32. On the other hand, the nonmagnetic conductor layer 80 connected to the second transistor TR2 is connected to the nonmagnetic layer 33 on the second region R2. The nonmagnetic conductor layer 80 is physically separated from the second magnetic recording layer 32, the nonmagnetic layer 40, and the spin supply layer 50. Alternatively, the nonmagnetic layer 33 may be extended so as to be directly connected to the second contact portion 90, and the nonmagnetic conductor layer 80 may be omitted. In any case, the third terminal T3 is connected to the nonmagnetic layer 33 of the magnetic recording layer 30 via the second transistor TR2.

  The voltage control, cell layout, etc. at the time of data reading / writing are the same as those in the first embodiment.

4). Fourth Embodiment FIG. 13 is a cross-sectional view showing a configuration of a memory cell 1 according to a fourth embodiment. The fourth embodiment is the same as the second embodiment described above except for the configuration of the magnetic recording layer 30. Description overlapping with the second embodiment is omitted as appropriate.

  In the present embodiment, the magnetic recording layer 30 includes a first magnetic recording layer 31, a second magnetic recording layer 32, and a nonmagnetic layer 33. The first magnetic recording layer 31 is a ferromagnetic layer whose magnetization direction can be reversed, and is in contact with the nonmagnetic layer 40. The second magnetic recording layer 32 is a ferromagnetic layer whose magnetization direction can be reversed, and is in contact with the tunnel barrier layer 20. The nonmagnetic layer 33 is sandwiched between the first magnetic recording layer 31 and the second magnetic recording layer 32. The nonmagnetic layer 33 is formed of a nonmagnetic conductive material such as Ru or Cu, for example.

  The first magnetic recording layer 31 and the second magnetic recording layer 32 are magnetically coupled to each other via the nonmagnetic layer 33. For example, the first magnetic recording layer 31 and the second magnetic recording layer 32 are antiferromagnetically coupled via the nonmagnetic layer 33. When the magnetization direction of the second magnetic recording layer 32 is reversed, the magnetization direction of the first magnetic recording layer 31 is also reversed accordingly.

  In FIG. 13, the upper surface of the first magnetic recording layer 31 has different first regions R1 and second regions R2. The second magnetic recording layer 32 is formed on the first region R1 via the nonmagnetic layer 33. The tunnel barrier layer 20 and the sense layer 10 are stacked on the second magnetic recording layer 32. On the other hand, the nonmagnetic conductor layer 80 connected to the second transistor TR2 is connected to the nonmagnetic layer 33 on the second region R2. The nonmagnetic layer conductor layer 80 is physically separated from the second magnetic recording layer 32, the tunnel barrier layer 20, and the sense layer 10. Alternatively, the nonmagnetic layer 33 may be extended so as to be directly connected to the second contact portion 90, and the nonmagnetic conductor layer 80 may be omitted. In any case, the third terminal T3 is connected to the nonmagnetic layer 33 of the magnetic recording layer 30 via the second transistor TR2.

  The voltage control, cell layout, etc. at the time of data reading / writing are the same as those in the second embodiment.

5. Fifth Embodiment FIG. 14 is a cross-sectional view showing a configuration of a memory cell 1 according to a fifth embodiment. The fifth embodiment is the same as the first embodiment described above, except for the configuration of the spin transfer unit SW. The description overlapping with the first embodiment is omitted as appropriate.

  In the present embodiment, the spin transfer unit SW includes the magnetic recording layer 30, the first nonmagnetic layer 40A, the first spin supply layer 50A, the second nonmagnetic layer 40B, and the second spin supply layer 50B. . The first nonmagnetic layer 40A is sandwiched between the magnetic recording layer 30 and the first spin supply layer 50A. The second nonmagnetic layer 40B is sandwiched between the magnetic recording layer 30 and the second spin supply layer 50B.

  More specifically, the top surface of the magnetic recording layer 30 has different first regions R1 and second regions R2. The first nonmagnetic layer 40A and the first spin supply layer 50A are formed on the first region R1. The first nonmagnetic layer 40A and the first spin supply layer 50A correspond to the nonmagnetic layer 40 and the spin supply layer 50 (see FIG. 6) in the first embodiment, respectively. An upper connection portion 70 is formed on 50A. On the other hand, the second nonmagnetic layer 40B and the second spin supply layer 50B are formed on the second region R2. The nonmagnetic conductor layer 80 connected to the second transistor TR2 is in contact with the second spin supply layer 50B, and the second region R2 of the magnetic recording layer 30 via the second spin supply layer 50B and the second nonmagnetic layer 40B. It is connected to the.

  Each of the first spin supply layer 50A and the second spin supply layer 50B is a ferromagnetic layer whose magnetization direction is fixed. Here, the fixed magnetization directions of the first spin supply layer 50A and the second spin supply layer 50B are opposite to each other. In the example shown in FIG. 14, the magnetization direction of the first spin supply layer 50A is fixed in the −X direction, and the magnetization direction of the second spin supply layer 50B is fixed in the + X direction. This improves the efficiency of spin transfer for the magnetic recording layer 30 during data writing. As a result, the write current Iw can be further reduced.

  The voltage control, cell layout, etc. at the time of data reading / writing are the same as those in the first embodiment.

6). Sixth Embodiment FIG. 15 is a cross-sectional view showing a configuration of a memory cell 1 according to a sixth embodiment. In the sixth embodiment, the configuration of the spin transfer unit SW is different from the second embodiment described above. Description overlapping with the second embodiment is omitted as appropriate.

  In the present embodiment, the spin transfer unit SW includes the magnetic recording layer 30, the first nonmagnetic layer 40A, the first spin supply layer 50A, the second nonmagnetic layer 40B, and the second spin supply layer 50B. . The first nonmagnetic layer 40A is sandwiched between the magnetic recording layer 30 and the first spin supply layer 50A. The second nonmagnetic layer 40B is sandwiched between the magnetic recording layer 30 and the second spin supply layer 50B.

  More specifically, the bottom surface of the magnetic recording layer 30 has different first regions R1 and second regions R2. The first nonmagnetic layer 40A and the first spin supply layer 50A are formed on the first region R1. The first nonmagnetic layer 40A and the first spin supply layer 50A correspond to the nonmagnetic layer 40 and the spin supply layer 50 (see FIG. 9) in the second embodiment, respectively. The first spin supply layer 50A is connected to the first transistor TR1 through the first contact portion 60. On the other hand, the second nonmagnetic layer 40B and the second spin supply layer 50B are formed on the second region R2. The second spin supply layer 50B is connected to the second transistor TR2 through the second contact portion 90. The nonmagnetic conductor layer 80 is omitted. The second transistor TR2 is connected to the second region R2 of the magnetic recording layer 30 via the second spin supply layer 50B and the second nonmagnetic layer 40B.

  Each of the first spin supply layer 50A and the second spin supply layer 50B is a ferromagnetic layer whose magnetization direction is fixed. Here, the fixed magnetization directions of the first spin supply layer 50A and the second spin supply layer 50B are opposite to each other. In the example shown in FIG. 15, the magnetization direction of the first spin supply layer 50A is fixed in the −X direction, and the magnetization direction of the second spin supply layer 50B is fixed in the + X direction. This improves the efficiency of spin transfer for the magnetic recording layer 30 during data writing. As a result, the write current Iw can be further reduced.

  The voltage control, cell layout, etc. at the time of data reading / writing are the same as those in the second embodiment.

  As long as there is no contradiction, two or more of the first to sixth embodiments described above may be combined.

7). Seventh Embodiment FIG. 16 schematically shows a configuration of a semiconductor integrated circuit (semiconductor chip) according to a seventh embodiment. This semiconductor integrated circuit is equipped with different types of first MRAM and second MRAM. That is, different types of first MRAM and second MRAM are integrated on one chip.

  The memory cell of the first MRAM is the memory cell 1 (three-terminal MTJ element) described in the above embodiments. That is, the first MRAM is a spin transfer type MRAM, and includes a plurality of memory cells 1 arranged in an array like the MRAM shown in FIG. On the other hand, the memory cell of the second MRAM is the memory cell 100 (two-terminal MTJ element) shown in FIG. That is, the second MRAM is a spin transfer MRAM, and includes a plurality of memory cells 100 arranged in an array.

  FIG. 17 is a cross-sectional view showing a memory cell configuration according to the present embodiment. Both the first MRAM memory cell 1 and the second MRAM memory cell 100 are formed on the same semiconductor substrate 5. As an example of the memory cell 1 of the first MRAM, the one described in the first embodiment is shown.

  The memory cell 100 of the second MRAM is connected to the fixed magnetization layer (sense layer) 110, the magnetic recording layer 130, the tunnel barrier layer 120 sandwiched between the fixed magnetization layer 110 and the magnetic recording layer 130, and the fixed magnetization layer 110. The fourth terminal T4 and the fifth terminal T5 connected to the magnetic recording layer 130 are provided. The fourth terminal T4 is connected to the third bit line BL3 extending in the Y direction. Further, a third transistor TR3 formed on the semiconductor substrate 5 is interposed between the fourth terminal T4 and the magnetization fixed layer 110. The gate electrode of the third transistor TR3 is connected to the third word line WL3 extending in the X direction. The fifth terminal T5 is connected to the upper wiring PL2 extending in the X direction.

  The manufacturing process of the memory cell 100 of the second MRAM is included in the manufacturing process of the memory cell 1 of the first MRAM. That is, when the memory cell 1 of the first MRAM is manufactured, the memory cell 100 of the second MRAM can be manufactured at the same time. For example, the magnetization fixed layer 110, the tunnel barrier layer 120, and the magnetic recording layer 130 of the memory cell 100 are formed in the same layer by the same process as the sense layer 10, the tunnel barrier layer 20, and the magnetic recording layer 30 of the memory cell 1, respectively. obtain. In addition, the manufacturing process of the upper wiring (PL, PL2), the transistors (TR1, TR2, TR3), the word lines (WL1, WL2, WL3), the bit lines (BL1, BL2, BL3), and the contact portion is also a memory cell. 1 and the memory cell 100 can be shared. Further, in the memory cell 100, the process of creating the spin supply layer 50, the nonmagnetic conductor layer 80, and the second contact portion 90 is not necessary.

  As described above, in this embodiment, two types of MRAM are formed on one chip. In the memory cell 1 (three-terminal MTJ element) of the first MRAM, the write current Iw does not penetrate the tunnel barrier layer 20 as described above. Therefore, deterioration of the tunnel barrier layer 20 does not occur, and the number of rewrites is virtually unlimited. The memory cell 1 also has a feature that high-speed writing and high-speed reading are possible. On the other hand, the memory cell 100 (two-terminal MTJ element) of the second MRAM has a feature that the cell size is smaller than that of the memory cell 1 (three-terminal MTJ element). Therefore, the first MRAM and the second MRAM can be used properly according to the application.

  For example, the present embodiment can be applied to a microcomputer chip. The main components of the MCU (microcomputer unit: microcomputer) are a CPU, SRAM, and flash memory, and these components are integrated on one chip (mixed memory chip). The SRAM is required to have characteristics such as (1) unlimited writing frequency, (2) high-speed writing, and (3) high-speed reading. On the other hand, flash memory is required to have characteristics such as (1) miniaturization of memory cells and (2) high-speed reading. Therefore, the SRAM and flash memory of the microcomputer chip can be replaced with the first MRAM and the second MRAM according to the present embodiment, respectively. Since the SRAM is replaced with a non-volatile MRAM, the dark current is greatly reduced. Further, as described above, the first MRAM and the second MRAM can be simultaneously created by the same manufacturing process, which is preferable.

  The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiments, and can be appropriately changed by those skilled in the art without departing from the scope of the invention.

  This application claims the priority on the basis of the Japan patent application 2009-222979 for which it applied on September 28, 2009, and takes in those the indications of all here.

Claims (10)

A spin transfer magnetic memory comprising a plurality of memory cells,
Each of the plurality of memory cells includes
A magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A sense layer including a ferromagnetic layer with a fixed magnetization direction;
A tunnel barrier layer sandwiched between the magnetic recording layer and the sense layer;
A first spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A first nonmagnetic layer sandwiched between the magnetic recording layer and the first spin supply layer;
A first terminal connected to the magnetic recording layer via the sense layer and the tunnel barrier layer;
A second terminal connected to the magnetic recording layer via the first spin supply layer and the first nonmagnetic layer;
A third terminal connected to the magnetic recording layer without passing through the sense layer, the tunnel barrier layer, the first spin supply layer, and the first nonmagnetic layer ;
Each of the memory cells further includes a first transistor and a second transistor formed on the substrate,
The sense layer, the tunnel barrier layer, the magnetic recording layer, the first nonmagnetic layer, and the first spin supply layer are stacked in this order from the substrate side,
One of the source and drain of the first transistor is connected to the first terminal, and the other is connected to the sense layer,
One of the source and drain of the second transistor is connected to the third terminal, the other is connected to the magnetic recording layer,
The first nonmagnetic layer is formed on a first region on the top surface of the magnetic recording layer,
The top surface of the magnetic recording layer has a second region different from the first region;
The other of the source and the drain of the second transistor is connected to the second region.
Magnetic memory. The magnetic memory according to claim 1,
The magnetic recording layer is
A first magnetic recording layer in contact with the tunnel barrier layer and capable of reversing the magnetization direction;
A second magnetic recording layer in contact with the first nonmagnetic layer and having a reversible magnetization direction;
A nonmagnetic layer sandwiched between the first magnetic recording layer and the second magnetic recording layer;
Have
The first magnetic recording layer and the second magnetic recording layer are magnetically coupled via the nonmagnetic layer,
The other of the source and the drain of the second transistor is connected to the nonmagnetic layer of the magnetic recording layer.
Magnetic memory. The magnetic memory according to claim 1,
Each of the memory cells has
A second spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A second nonmagnetic layer sandwiched between the magnetic recording layer and the second spin supply layer;
Further comprising
The second nonmagnetic layer is formed on the second region;
The other of the source and the drain of the second transistor is connected to the second region via the second spin supply layer and the second nonmagnetic layer,
The fixed magnetization directions of the first spin supply layer and the second spin supply layer are opposite to each other.
Magnetic memory. A spin transfer magnetic memory comprising a plurality of memory cells,
Each of the plurality of memory cells includes
A magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A sense layer including a ferromagnetic layer with a fixed magnetization direction;
A tunnel barrier layer sandwiched between the magnetic recording layer and the sense layer;
A first spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A first nonmagnetic layer sandwiched between the magnetic recording layer and the first spin supply layer;
A first terminal connected to the magnetic recording layer via the sense layer and the tunnel barrier layer;
A second terminal connected to the magnetic recording layer via the first spin supply layer and the first nonmagnetic layer;
A third terminal connected to the magnetic recording layer without passing through the sense layer, the tunnel barrier layer, the first spin supply layer, and the first nonmagnetic layer;
Each of the memory cells further includes a first transistor and a second transistor formed on the substrate,
The first spin supply layer, the first nonmagnetic layer, the magnetic recording layer, the tunnel barrier layer, and the sense layer are stacked in this order from the substrate side,
One of the source and the drain of the first transistor is connected to the second terminal, and the other is connected to the first spin supply layer.
One of the source and drain of the second transistor is connected to the third terminal, the other is connected to the magnetic recording layer,
The tunnel barrier layer is formed on the first region of the upper surface of the magnetic recording layer;
The top surface of the magnetic recording layer has a second region different from the first region;
The other of the source and the drain of the second transistor is connected to the second region.
Magnetic memory. The magnetic memory according to claim 4,
The magnetic recording layer is
A first magnetic recording layer in contact with the first nonmagnetic layer and having a reversible magnetization direction;
A second magnetic recording layer in contact with the tunnel barrier layer and capable of reversing the magnetization direction;
A nonmagnetic layer sandwiched between the first magnetic recording layer and the second magnetic recording layer;
Have
The first magnetic recording layer and the second magnetic recording layer are magnetically coupled via the nonmagnetic layer,
The other of the source and the drain of the second transistor is connected to the nonmagnetic layer of the magnetic recording layer.
Magnetic memory. The magnetic memory according to claim 4,
Each of the memory cells has
A second spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A second nonmagnetic layer sandwiched between the magnetic recording layer and the second spin supply layer;
Further comprising
The first nonmagnetic layer is formed on a first region of a bottom surface of the magnetic recording layer;
The bottom surface of the magnetic recording layer has a second region different from the first region;
The second nonmagnetic layer is formed on the second region;
The other of the source and the drain of the second transistor is connected to the second region via the second spin supply layer and the second nonmagnetic layer,
The fixed magnetization directions of the first spin supply layer and the second spin supply layer are opposite to each other.
Magnetic memory. The magnetic memory according to any one of claims 4 to 6,
The gate electrode of the first transistor and the gate electrode of the second transistor are connected to a common word line.
Magnetic memory. A spin transfer type first magnetic memory comprising a plurality of first memory cells;
A spin transfer type second magnetic memory comprising a plurality of second memory cells;
Comprising
Each of the plurality of first memory cells includes:
A first magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A first sense layer including a ferromagnetic layer with a fixed magnetization direction;
A first tunnel barrier layer sandwiched between the first magnetic recording layer and the first sense layer;
A first spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A first nonmagnetic layer sandwiched between the first magnetic recording layer and the first spin supply layer;
A first terminal connected to the first magnetic recording layer via the first sense layer and the first tunnel barrier layer;
A second terminal connected to the first magnetic recording layer via the first spin supply layer and the first nonmagnetic layer;
A third terminal connected to the first magnetic recording layer without passing through the first sense layer, the first tunnel barrier layer, the first spin supply layer, and the first nonmagnetic layer;
With
Each of the plurality of second memory cells includes:
A second magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A second sense layer including a ferromagnetic layer with a fixed magnetization direction;
A second tunnel barrier layer sandwiched between the second magnetic recording layer and the second sense layer;
A fourth terminal connected to the second sense layer;
A fifth terminal connected to the second magnetic recording layer,
Each of the first memory cells further includes a first transistor and a second transistor formed on the substrate,
The first sense layer, the first tunnel barrier layer, the first magnetic recording layer, the first nonmagnetic layer, and the first spin supply layer are stacked in this order from the substrate side,
One of the source and drain of the first transistor is connected to the first terminal, and the other is connected to the first sense layer,
One of the source and drain of the second transistor is connected to the third terminal, and the other is connected to the first magnetic recording layer.
The first nonmagnetic layer is formed on a first region of the upper surface of the first magnetic recording layer;
The upper surface of the first magnetic recording layer has a second region different from the first region;
The other of the source and the drain of the second transistor is connected to the second region.
Semiconductor integrated circuit. A spin transfer type first magnetic memory comprising a plurality of first memory cells;
A spin transfer type second magnetic memory comprising a plurality of second memory cells;
Comprising
Each of the plurality of first memory cells includes:
A first magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A first sense layer including a ferromagnetic layer with a fixed magnetization direction;
A first tunnel barrier layer sandwiched between the first magnetic recording layer and the first sense layer;
A first spin supply layer including a ferromagnetic layer having a fixed magnetization direction;
A first nonmagnetic layer sandwiched between the first magnetic recording layer and the first spin supply layer;
A first terminal connected to the first magnetic recording layer via the first sense layer and the first tunnel barrier layer;
A second terminal connected to the first magnetic recording layer via the first spin supply layer and the first nonmagnetic layer;
A third terminal connected to the first magnetic recording layer without passing through the first sense layer, the first tunnel barrier layer, the first spin supply layer, and the first nonmagnetic layer;
With
Each of the plurality of second memory cells includes:
A second magnetic recording layer including a ferromagnetic layer whose magnetization direction is reversible;
A second sense layer including a ferromagnetic layer with a fixed magnetization direction;
A second tunnel barrier layer sandwiched between the second magnetic recording layer and the second sense layer;
A fourth terminal connected to the second sense layer;
A fifth terminal connected to the second magnetic recording layer,
Each of the first memory cells further includes a first transistor and a second transistor formed on the substrate,
The first spin supply layer, the first nonmagnetic layer, the first magnetic recording layer, the first tunnel barrier layer, and the first sense layer are stacked in this order from the substrate side,
One of the source and the drain of the first transistor is connected to the second terminal, and the other is connected to the first spin supply layer.
One of the source and drain of the second transistor is connected to the third terminal, and the other is connected to the first magnetic recording layer.
The tunnel barrier layer is formed on a first region of an upper surface of the first magnetic recording layer;
The upper surface of the first magnetic recording layer has a second region different from the first region;
The other of the source and the drain of the second transistor is connected to the second region.
Semiconductor integrated circuit. A semiconductor integrated circuit according to claim 8 or 9, wherein
The first magnetic recording layer and the second magnetic recording layer are formed in the same layer,
The first tunnel barrier layer and the second tunnel barrier layer are formed in the same layer,
The first sense layer and the second sense layer are formed in the same layer.
Semiconductor integrated circuit.

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