CN112951980A - Magnetic tunnel junction vertical anisotropy field enhancement layer and random access memory - Google Patents
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Abstract
The invention relates to the field of magnetic random access memories, in particular to a magnetic tunnel junction vertical anisotropy field enhancement layer; the perpendicular anisotropy field enhancement layer is arranged in the storage unit of the magnetic random access memory, the perpendicular anisotropy field enhancement layer is a double-layer structure of a first perpendicular anisotropy field enhancement layer and a second perpendicular anisotropy field enhancement layer which are formed through a sputtering deposition process, and the perpendicular anisotropy field of the free layer is enhanced through the template effect of the HCP crystal orientation of the second perpendicular anisotropy field enhancement layer by the first perpendicular anisotropy field enhancement layer; the invention is beneficial to improving the read/write performance of the MRAM circuit and the magnetic field immunity, is beneficial to manufacturing the ultra-small MRAM circuit, and has strong market application prospect.
Description
Technical Field
The invention relates to the field of magnetic random access memories, in particular to a magnetic tunnel junction vertical anisotropy field enhancement layer.
Background
In recent years, Magnetic Random Access Memory (MRAM) using Magnetic Tunnel Junction (MTJ) is considered as a future solid-state nonvolatile Memory, which has the characteristics of high speed reading and writing, large capacity, and low power consumption. Ferromagnetic MTJs are typically sandwich structures with a magnetic memory layer (free layer) that can change the magnetization direction to record different data; an insulating tunnel barrier layer in the middle; and the magnetic reference layer is positioned on the other side of the tunnel barrier layer, and the magnetization direction of the magnetic reference layer is unchanged.
In order to be able to record information in such a magnetoresistive element, a writing method based on Spin momentum Transfer (STT) switching technology has been proposed, and such an MRAM is called STT-MRAM. STT-MRAM is further classified into in-plane STT-MRAM and perpendicular STT-MRAM (i.e., pSTT-MRAM), which have better performance depending on the direction of magnetic polarization. In a Magnetic Tunnel Junction (MTJ) with perpendicular anisotropy (PMA), as a free layer for storing information, two magnetization directions are possessed in the perpendicular direction, that is: up and down, corresponding to "0" and "1" in the binary, respectively. In practical application, the magnetization direction of the free layer is kept unchanged when information is read or the free layer is empty; during writing, if a signal of a different state from that of the prior art is input, the magnetization direction of the free layer is inverted by one hundred and eighty degrees in the vertical direction. The ability of the free layer of a magnetic memory to maintain a constant magnetization direction in this empty state is known in the industry as data retention or thermal stability.
The requirements are different in different application scenarios. For a typical non-volatile memory, for example: the requirement of thermal stability for application in automotive electronics is to preserve data for at least ten years at 125 c or even 150 c.
To achieve fast writing of a logic "0" or "1", a typical write requires that the write current density (J) be greater than the critical current density: (J) ((1))Jc0). Wherein,
time of writing is tpwThen, there are:
the write current (J) exceeds the critical current (J)c0) The ratio of the fraction (J) to the critical current is J, J being J/Jc0-1。
Wherein alpha is a secondary damping coefficient,
to approximate Planck constant, MsIs the saturation susceptibility of the free layer, t is the effective thickness of the free layer, HKIs a perpendicular effective anisotropy field, kBIs the Boltzmann constant, T is the temperature, η spin polarizability, γ is the gyromagnetic ratio, Δ is the thermodynamic stability factor of the magnetic tunnel to junction (MTJ), τrelaxRelaxation time, θ0The angle is initialized for the free layer magnetization vector.
In fast caches, for example: as an alternative to SRAM, MRAM is required to have a read and write speed that matches SRAM.
In addition, MTJ, which is a core memory cell of a magnetic memory (MRAM), must also be compatible with CMOS processes and must be able to withstand long term annealing at 350 ℃ or higher; meanwhile, a Magnetic memory cell of MRAM is required to have strong Magnetic Immunity (Magnetic Immunity).
In conventional structures, the free layer is typically composed of CoFeB/(Zr, V, Cr, Nb, Tc, Ta, W, Mo, Hf)/CoFeB or Fe/CoFeB/(Zr, V, Cr, Nb, Tc, Ta, W, Mo, Hf)/CoFeB, etc. A layer of MgO is arranged on the free layer, and the MgO/free layer has vertical anisotropy, so that the thermal stability of the MTJ unit structure is enhanced.
In recent years, the Critical Dimension (CD) of the magnetic Tunnel junction is getting smaller, the junction Resistance Area (RA) is also getting smaller to match the Resistance of the CMOS circuit, and it is required to maintain a relatively high Tunneling Magnetoresistance Ratio (TMR) to ensure a high read speed.
Disclosure of Invention
Aiming at the defects of the prior art, the invention discloses a perpendicular anisotropic field enhancement layer of a magnetic tunnel junction, which is used for solving the problems that the key size of the existing magnetic tunnel junction is smaller and smaller, the junction resistance area is smaller and smaller in order to be matched with the impedance of a CMOS circuit, and the relatively higher tunneling magnetic resistance rate is required to be kept to ensure the higher reading speed.
The invention is realized by the following technical scheme:
in a first aspect, the present invention provides a perpendicular anisotropy field enhancement layer of a magnetic tunnel junction, where the perpendicular anisotropy field enhancement layer is disposed in a memory cell of a magnetic random access memory, the perpendicular anisotropy field enhancement layer is a double-layer structure including a first perpendicular anisotropy field enhancement layer formed by a sputter deposition process and a second perpendicular anisotropy field enhancement layer, and the first perpendicular anisotropy field enhancement layer enhances a perpendicular anisotropy field of a free layer by a template effect of an HCP crystal orientation of the second perpendicular anisotropy field enhancement layer.
Furthermore, the material of the first vertical anisotropic field enhancement layer is MgOxThe thickness is 0.2 nm-0.8 nm.
Further, the second perpendicular anisotropy field enhancement layer (2nd HK EL)272 has a total thickness of 0.4nm to 5.0nm, and is made of Co, Tc, Ru, Re, Os, Ir, Co1-yFey, Tc1-yCoy, Tc1-yFey, Tc1-y (CoFe) y, Ru1-yCoy, Ru1-yFey, Ru1-y (CoFe) y, Re1-yCoy, Re1-yFey, Re1-y (CoFe) y, Os1-yCoy, Os1-yFey, Os1-y (CoFe) y, Ir1-yCoy, Ir1-yFey, Ir1-y (Fe) y, [ Tc/Co ] m, [ Tc/CoFe ] m, [ Tc/m ] m, [ Ru/Tc ] m, [ Ru/Tc/Fe ] m, [ Ru/Tc/m ], [ Co/Ru ] m, [ CoFe/Ru ] m, [ Fe/Ru ] m, [ Re/Co ] m, [ Re/CoFe ] m, [ Re/Fe ] m, [ Co/Re ] m, [ CoFe/Re ] m, [ Fe/Re ] m, [ Os/Co ] m, [ Os/CoFe ] m, [ Os/Fe ] m, [ Co/Os ] m, [ CoFe/Os ] m, [ Fe/Os ] m, wherein y is not more than 20%, and m is not less than 0 and not more than 5.
Furthermore, the sputtering deposition process is to form a first vertical anisotropic field enhancement layer by sputtering deposition of the MgO ceramic target;
the sputtering deposition process comprises the steps of firstly carrying out sputtering deposition on an Mg metal target, then oxidizing a sputtering deposited Mg film to form MgO, and finally forming a first vertical anisotropic field enhancement layer;
the sputtering deposition process comprises the steps of firstly sputtering a MgO ceramic target, then sputtering and depositing an Mg metal target, and finally performing an oxidation process to form a first vertical anisotropic field enhancement layer.
In a second aspect, the present invention provides a magnetic random access memory, which includes a memory cell including the magnetic tunnel junction perpendicular anisotropy field enhancement layer of the first aspect, and further includes a bottom electrode and a top electrode, wherein the memory cell includes a seed layer, a synthetic antiferromagnetic layer, a lattice partition layer, a reference layer, a barrier layer, a free layer, a perpendicular anisotropy field enhancement layer, a diffusion barrier layer, and an etching barrier layer, which are stacked.
Furthermore, the bottom electrode, the seed layer, the synthetic antiferromagnetic layer, the lattice partition layer, the reference layer, the barrier layer, the free layer, the vertical anisotropic field enhancement layer, the diffusion barrier layer, the etching barrier layer and the top electrode are sequentially stacked.
Furthermore, the bottom electrode is made of Ti, TiN, Ta, TaN, W, Ru, WN or a combination thereof;
the seed layer is composed of Ta, Ti, TiN, TaN, W, WN, Ru, Pt, Ni, Cr, CrNi, CrCo, CoFeB or the combination thereof;
the synthetic antiferromagnetic layer has superlattice structure of [ Co/Pt ] nCo/Ru, [ Co/Pt ] nCo/Ir, [ Co/Pt ] nCo/Ru/Co, [ Co/Pt ] nCo/Ir/Co [ Co/Pt ] nCo/Ru/Co, [ Pt/Co ] m or [ Co/Pt ] nCo/Ir/Co [ Pt/Co ] m;
the reference layer is made of Co, Fe, Ni, CoFe, CoFeB or a combination thereof;
the lattice partition layer is made of Ta, W, Mo, Hf, Fe, Co (Ta, Zr, Nb, V, Cr, W, Mo or Hf), Fe (Ta, Zr, Nb, V, Cr, W, Mo or Hf), FeCo (Ta, Zr, Nb, V, Cr, W, Mo or Hf) or FeCoB (Ta, Zr, Nb, V, Cr, W, Mo or Hf);
the total thickness of the barrier layer is 0.6 nm-1.5 nm, and the barrier layer is made of MgO;
the free layer has a CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB, Fe/CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB or CoFe/CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB structure;
the diffusion barrier layer is made of Zr, Nb, Ti, V, Cr, W, Hf, Mo, Tc, Y or the combination thereof, the thickness of the diffusion barrier layer is z, and the z is more than 0.0 and less than or equal to 8.0 nm;
the etching barrier layer 29 is made of Ru, Ir or a combination thereof, and the thickness of the etching barrier layer is 1.0-10.0 nm;
the top electrode is Ta, TaN, TaN/Ta, Ti, TiN, TiN/Ti, W, WN, WN/W or a combination thereof.
Furthermore, the seed layer is a multilayer structure of Ta/Ru, CoFeB/Ta/Pt, CoFeB/Ta/Ru, CoFeB/Ta/Ru/Pt, Ta/Pt or Ta/Pt/Ru.
Furthermore, the barrier layer is realized by directly carrying out sputtering deposition on the MgO target material, or is realized by firstly carrying out sputtering deposition on the Mg target material and then changing the Mg into the MgO through an oxidation process.
Furthermore, when the magnetic random access memory is constructed, after the bottom electrode, the seed layer, the synthetic antiferromagnetic layer, the crystal lattice partition layer, the reference layer, the MgO barrier layer, the free layer, the vertical anisotropy field enhancement layer, the diffusion barrier layer, the etching barrier layer and the top electrode are deposited, the annealing operation is carried out for more than 30 minutes at the temperature of no less than 350 ℃.
The invention has the beneficial effects that:
the invention is beneficial to improving the read/write performance of the MRAM circuit and the magnetic field immunity, is beneficial to manufacturing the ultra-small MRAM circuit, and has strong market application prospect.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a diagram illustrating a MRAM cell according to an embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
This embodiment discloses a unit structure of magnetic tunnel junction vertical anisotropy field enhancement layer, vertical anisotropy field enhancement layer (H)KEnhancement Layer, HK EL)27 is the first vertical anisotropy field Enhancement Layer (1)st HKEL)271 and a second perpendicular anisotropy field enhancement layer (2)ndHKEL) 272.
First perpendicular anisotropy field enhancement layer (1)st HKEL)271 is MgOxThe thickness of the film is 0.2 nm-0.8 nm, and the forming mode can be realized by (1) carrying out sputtering deposition on an MgO ceramic target; (2) or the Mg metal target is firstly subjected to sputtering deposition, and then the sputtering deposited Mg film is oxidized to form MgO; even (3) sputtering can be performed on a MgO ceramic target first, and then on a Mg metal targetSputtering deposition and finally, oxidation process.
Second perpendicular anisotropy field enhancement layer (2)nd HKEL)272 has a total thickness of 0.4 to 5.0nm, and is made of a material having HCP structure of Co, Tc, Ru, Re, Os, Ir, Co1-yFey, Tc1-yCoy, Tc1-yFey, Tc1-y (CoFe) y, Ru1-yCoy, Ru1-yFey, Ru1-y (CoFe) y, Re1-yCoy, Re1-yFey, Re1-y (CoFe) y, Os1-yCoy, Os1-yFey, Os1-y (CoFe) y, Ir1-yCoy, Ir1-yFey, Ir1-y (CoFe) y, [ Tc/Co ] y]m，[Tc/CoFe]m，[Tc/Fe]m，[Co/Tc]m，[CoFe/Tc]m，[Fe/Tc]m，[Ru/Co]m，[Ru/CoFe]m，[Ru/Fe]m，[Co/Ru]m，[CoFe/Ru]m，[Fe/Ru]m，[Re/Co]m，[Re/CoFe]m，[Re/Fe]m，[Co/Re]m，[CoFe/Re]m，[Fe/Re]m,[Os/Co]m，[Os/CoFe]m，[Os/Fe]m，[Co/Os]m，[CoFe/Os]m，[Fe/Os]m, wherein y is not more than 20 percent, and m is not less than 0 and not more than 5.
First perpendicular anisotropy field enhancement layer (1)st HKEL)271 in a second perpendicular anisotropy field enhancement layer (2)nd HKEL)272 first vertical anisotropy field enhancement layer (1) under templating action of HCP crystal system (0001) crystal orientationst HKEL)271 has better crystallization properties. Thereby enhancing the perpendicular anisotropy field (H) of the free layerK)。
The magnetic tunnel junction vertical anisotropy field enhancement layer structure is beneficial to improving the reading/writing performance of an MRAM circuit and the magnetic field immunity of the MRAM circuit, and is beneficial to manufacturing an ultra-small MRAM circuit.
Example 2
The embodiment discloses a magnetic random access memory, which comprises the memory cell as described above, and further comprises a bottom electrode 10 and a top electrode 30, wherein the bottom electrode 10, a seed layer 21, a synthetic antiferromagnetic layer 22, a lattice partition layer 23, a reference layer 24, a barrier layer 25, a free layer 26, a vertical anisotropy field enhancement layer 27, a diffusion barrier layer 28, an etching barrier layer 29 and the top electrode 30 are sequentially stacked.
The magnetic random access memory cell shown in fig. 1 comprises a seed layer 21, a synthetic antiferromagnetic layer 22, a lattice blocking layer 23, a reference layer 24, a barrier layer 25, a free layer 26, a vertical anisotropy field enhancement layer 27, a diffusion barrier layer 28 and an etch stop layer 29, which are arranged in a stack.
The bottom electrode 10 is made of Ti, TiN, Ta, TaN, W, Ru, WN or a combination thereof, and is generally implemented by Physical Vapor Deposition (PVD), and after Deposition, planarization of the bottom electrode 10 is usually selected to achieve surface flatness for fabricating the magnetic tunnel junction.
The seed layer 21 is generally composed of Ta, Ti, TiN, TaN, W, WN, Ru, Pt, Ni, Cr, CrNi, CrCo, CoFeB or a combination thereof, and may have a multilayer structure of Ta/Ru, CoFeB/Ta/Pt, CoFeB/Ta/Ru, CoFeB/Ta/Ru/Pt, Ta/Pt or Ta/Pt/Ru. To optimize the crystal structure of the subsequent synthetic antiferromagnetic layer 220.
The synthetic Anti-ferromagnetic layer (SyAF)22 has [ Co/Pt ]]nCo/Ru、[Co/Pt]nCo/Ir、[Co/Pt]nCo/Ru/Co、[Co/Pt]nCo/Ir/Co、[Co/Pt]nCo/Ru/Co[Pt/Co]m or [ Co/Pt ]]nCo/Ir/Co[Pt/Co]m a superlattice structure, wherein n>m.gtoreq.1, the synthetic antiferromagnetic layer 20 has a strong perpendicular anisotropy (PMA).
The reference layer 24 is magnetically polarization invariant under ferromagnetic coupling of the antiferromagnetic layer 22 and is typically comprised of Co, Fe, Ni, CoFe, CoFeB, combinations thereof or the like. Since the synthetic antiferromagnetic layer (SyAF)22 has a Face Centered Cubic (FCC) crystal structure and the reference layer 24 has a Body Centered Cubic (BCC) crystal structure, the lattices are not matched, and in order to achieve the transition and ferromagnetic coupling from the synthetic antiferromagnetic layer (SyAF)22 to the reference layer 24, a lattice-blocking layer 23 is typically added between two layers of material, typically Ta, W, Mo, Hf, Fe, Co (Ta, Zr, Nb, V, Cr, W, Mo or Hf), Fe (Ta, Zr, Nb, V, Cr, W, Mo or Hf), FeCo (Ta, Zr, Nb, V, Cr, W, Mo or Hf) or FeCoB (Ta, Zr, Nb, V, Cr, W, Mo or Hf), etc.
The total thickness of the barrier layer 25 is 0.6nm to 1.5 nm. The material is MgO, and the method can be realized by directly sputtering and depositing the MgO target material, or by firstly sputtering and depositing Mg on the Mg target material and then changing the Mg into the MgO through an oxidation process.
The free layer 26 has a CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB, Fe/CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB or CoFe/CoFeB/(W, Mo, V, Nb, Cr, Hf, Ti, Zr, Ta, Sc, Y, Zn, Ru, Os, Ru, Rh, Ir, Pd, Pt)/CoFeB structure. Further, optionally, a plasma process may be used to perform surface plasma treatment after the free layer deposition for surface modification or selective removal.
The Diffusion Barrier Layer (DB) 28 is made of Zr, Nb, Ti, V, Cr, W, Hf, Mo, Tc, Y, or a combination thereof. The thickness is z, and the z is more than 0.0 and less than or equal to 8.0 nm. Its main role is to prevent the elements in the top electrode from diffusing into the vertical anisotropy field enhancement layer, even the free layer, etc.
The material of the etching barrier layer 29 is Ru, Ir or the combination of the Ru and the Ir, the thickness of the etching barrier layer is 1.0 nm-10.0 nm, and the etching barrier layer is mainly used as an etching barrier layer for subsequent etching.
The top electrode 30 may be selected from Ta, TaN, TaN/Ta, Ti, TiN, TiN/Ti, W, WN, WN/W or combinations thereof.
When the magnetic random access memory is constructed, after the bottom electrode, the seed layer, the synthetic antiferromagnetic layer, the crystal lattice partition layer, the reference layer, the MgO barrier layer, the free layer, the vertical anisotropic field enhancement layer, the diffusion barrier layer, the etching barrier layer and the top electrode are deposited, annealing operation is carried out for at least 30 minutes at a temperature of no less than 350 ℃.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (8)
1. The magnetic tunnel junction vertical anisotropy field enhancement layer is arranged on a storage unit of a magnetic random access memory and is characterized in that the vertical anisotropy field enhancement layer is of a double-layer structure of a first vertical anisotropy field enhancement layer and a second vertical anisotropy field enhancement layer which are formed through a sputtering deposition process, and the vertical anisotropy field of a free layer is enhanced through the template effect of the HCP crystal system crystal orientation of the second vertical anisotropy field enhancement layer by the first vertical anisotropy field enhancement layer.
2. The magnetic tunnel junction perpendicular anisotropy field enhancement layer of claim 1, wherein the material of the first perpendicular anisotropy field enhancement layer is MgOxThe thickness is 0.2 nm-0.8 nm.
3. The magnetic tunnel junction perpendicular anisotropy field enhancement layer of claim 1, wherein the second perpendicular anisotropy field enhancement layer has a total thickness of 0.4nm to 5.0nm, and is made of Co, Tc, Ru, Re, Os, Ir, Co1-yFey, Tc1-yCoy, Tc1-yFey, Tc1-y (CoFe) y, Ru1-yCoy, Ru1-yFey, Ru1-y (CoFe) y, Re1-yCoy, Re1-yFey, Re1-y CoFe) y, Os1-yCoy, Os1-yFey, Os1-y (CoFe) y, Ir1-yCoy, Ir1-yFey, Ir1-y (CoFe) y, [ Tc/Co ] m, [ Tc/Tc ] m ] Fe/Tc, [ Co/Tc ] m ] Fe/Tc ], [ Ru/CoFe ] m, [ Ru/Fe ] m, [ Co/Ru ] m, [ CoFe/Ru ] m, [ Fe/Ru ] m, [ Re/Co ] m, [ Re/CoFe ] m, [ Re/Fe ] m, [ Co/Re ] m, [ CoFe/Re ] m, [ Fe/Re ] m, [ Os/Co ] m, [ Os/CoFe ] m, [ Os/Fe ] m, [ Fe/Os ] m, wherein y is not more than 20%, and m is not less than 0 and not more than 5.
4. The perpendicular anisotropy field enhancement layer of claim 1, wherein the sputter deposition process is to form a first perpendicular anisotropy field enhancement layer by sputter depositing a MgO ceramic target;
the sputtering deposition process comprises the steps of firstly carrying out sputtering deposition on an Mg metal target, then oxidizing a sputtering deposited Mg film to form MgO, and finally forming a first vertical anisotropic field enhancement layer;
the sputtering deposition process comprises the steps of firstly sputtering a MgO ceramic target, then sputtering and depositing an Mg metal target, and finally performing an oxidation process to form a first vertical anisotropic field enhancement layer.
5. A magnetic random access memory comprising a memory cell comprising the magnetic tunnel junction perpendicular anisotropy field enhancement layer according to any of claims 1-4, further comprising a bottom electrode and a top electrode, wherein the memory cell comprises a seed layer, a synthetic antiferromagnetic layer, a lattice-blocking layer, a reference layer, a barrier layer, a free layer, a perpendicular anisotropy field enhancement layer, a diffusion barrier layer, and an etch stop layer, which are stacked.
6. The magnetic random access memory according to claim 5, wherein the bottom electrode, the seed layer, the synthetic antiferromagnetic layer, the lattice-blocking layer, the reference layer, the barrier layer, the free layer, the vertical anisotropy field enhancement layer, the diffusion barrier layer, and the top electrode are sequentially stacked.
7. The MRAM of claim 5, wherein the diffusion barrier layer is Zr, Nb, Ti, V, Cr, W, Hf, Mo, Tc, Y, or combinations thereof, and has a thickness z, 0.0< z ≦ 8.0 nm;
the etching barrier layer 29 is made of Ru, Ir or a combination thereof, and the thickness of the etching barrier layer is 1.0-10.0 nm.
8. The magnetic random access memory according to claim 5, wherein the magnetic random access memory is constructed by performing an annealing operation at a temperature of not less than 350 ℃ for more than 30 minutes after the deposition of the bottom electrode, the seed layer, the synthetic antiferromagnetic layer, the lattice-blocking layer, the reference layer, the MgO barrier layer, the free layer, the vertical anisotropy field enhancement layer, the diffusion barrier layer, the etch barrier layer, and the top electrode.
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