CN113346007A - Magnetic tunnel junction structure and magnetic random access memory thereof - Google Patents
Magnetic tunnel junction structure and magnetic random access memory thereof Download PDFInfo
- Publication number
- CN113346007A CN113346007A CN202010136585.5A CN202010136585A CN113346007A CN 113346007 A CN113346007 A CN 113346007A CN 202010136585 A CN202010136585 A CN 202010136585A CN 113346007 A CN113346007 A CN 113346007A
- Authority
- CN
- China
- Prior art keywords
- layer
- magnetic tunnel
- magnetic
- tunnel junction
- junction structure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 104
- 230000005290 antiferromagnetic effect Effects 0.000 claims abstract description 69
- 230000008878 coupling Effects 0.000 claims description 36
- 238000010168 coupling process Methods 0.000 claims description 36
- 238000005859 coupling reaction Methods 0.000 claims description 36
- 229910052750 molybdenum Inorganic materials 0.000 claims description 28
- 229910052721 tungsten Inorganic materials 0.000 claims description 26
- 229910052735 hafnium Inorganic materials 0.000 claims description 17
- 229910052707 ruthenium Inorganic materials 0.000 claims description 17
- 229910019236 CoFeB Inorganic materials 0.000 claims description 16
- 239000002131 composite material Substances 0.000 claims description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 16
- 229910052758 niobium Inorganic materials 0.000 claims description 15
- 229910052715 tantalum Inorganic materials 0.000 claims description 15
- 229910052720 vanadium Inorganic materials 0.000 claims description 14
- -1 CrW Inorganic materials 0.000 claims description 13
- 229910052726 zirconium Inorganic materials 0.000 claims description 13
- 229910001149 41xx steel Inorganic materials 0.000 claims description 12
- 229910052804 chromium Inorganic materials 0.000 claims description 11
- 229910052741 iridium Inorganic materials 0.000 claims description 11
- 229910052703 rhodium Inorganic materials 0.000 claims description 11
- 230000004888 barrier function Effects 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 9
- 229910003321 CoFe Inorganic materials 0.000 claims description 8
- 229910052802 copper Inorganic materials 0.000 claims description 7
- 229910052742 iron Inorganic materials 0.000 claims description 7
- 229910052702 rhenium Inorganic materials 0.000 claims description 7
- 229910052759 nickel Inorganic materials 0.000 claims description 4
- 229910019170 CoC Inorganic materials 0.000 claims description 3
- 229910002441 CoNi Inorganic materials 0.000 claims description 3
- 229910018936 CoPd Inorganic materials 0.000 claims description 3
- 229910018979 CoPt Inorganic materials 0.000 claims description 3
- 229910015391 FeC Inorganic materials 0.000 claims description 3
- 229910015187 FePd Inorganic materials 0.000 claims description 3
- 229910005335 FePt Inorganic materials 0.000 claims description 3
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 claims description 3
- 229910003266 NiCo Inorganic materials 0.000 claims description 3
- 230000005294 ferromagnetic effect Effects 0.000 abstract description 16
- 230000033228 biological regulation Effects 0.000 abstract description 3
- 230000005611 electricity Effects 0.000 abstract description 3
- 230000005389 magnetism Effects 0.000 abstract description 3
- 229920006395 saturated elastomer Polymers 0.000 abstract description 3
- 230000002349 favourable effect Effects 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 164
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 24
- 239000011651 chromium Substances 0.000 description 22
- 239000010955 niobium Substances 0.000 description 18
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 15
- 239000010948 rhodium Substances 0.000 description 14
- 230000005415 magnetization Effects 0.000 description 13
- 239000010936 titanium Substances 0.000 description 13
- 239000000395 magnesium oxide Substances 0.000 description 11
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 11
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 11
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 10
- 229910052697 platinum Inorganic materials 0.000 description 9
- 239000010937 tungsten Substances 0.000 description 9
- 239000011701 zinc Substances 0.000 description 9
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 8
- 239000011777 magnesium Substances 0.000 description 8
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 8
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 7
- 239000013078 crystal Substances 0.000 description 7
- 230000014759 maintenance of location Effects 0.000 description 7
- 239000011733 molybdenum Substances 0.000 description 7
- 229910052796 boron Inorganic materials 0.000 description 6
- FQMNUIZEFUVPNU-UHFFFAOYSA-N cobalt iron Chemical compound [Fe].[Co].[Co] FQMNUIZEFUVPNU-UHFFFAOYSA-N 0.000 description 6
- 238000000151 deposition Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 6
- 229910052719 titanium Inorganic materials 0.000 description 6
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 5
- 230000008021 deposition Effects 0.000 description 5
- 238000005240 physical vapour deposition Methods 0.000 description 5
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 5
- 229910052718 tin Inorganic materials 0.000 description 5
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 5
- 229910052725 zinc Inorganic materials 0.000 description 5
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 4
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 229910052762 osmium Inorganic materials 0.000 description 4
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 4
- 229910052763 palladium Inorganic materials 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 4
- 229910052706 scandium Inorganic materials 0.000 description 4
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 description 4
- 229910052723 transition metal Inorganic materials 0.000 description 4
- 150000003624 transition metals Chemical class 0.000 description 4
- 229910052727 yttrium Inorganic materials 0.000 description 4
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 4
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 3
- 238000000137 annealing Methods 0.000 description 3
- 230000014509 gene expression Effects 0.000 description 3
- 238000009813 interlayer exchange coupling reaction Methods 0.000 description 3
- 229910052749 magnesium Inorganic materials 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000007769 metal material Substances 0.000 description 3
- 239000013598 vector Substances 0.000 description 3
- XLOMVQKBTHCTTD-UHFFFAOYSA-N zinc oxide Inorganic materials [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 3
- 229910019791 Mg3B2 Inorganic materials 0.000 description 2
- 229910004166 TaN Inorganic materials 0.000 description 2
- WRSVIZQEENMKOC-UHFFFAOYSA-N [B].[Co].[Co].[Co] Chemical compound [B].[Co].[Co].[Co] WRSVIZQEENMKOC-UHFFFAOYSA-N 0.000 description 2
- ZDZZPLGHBXACDA-UHFFFAOYSA-N [B].[Fe].[Co] Chemical compound [B].[Fe].[Co] ZDZZPLGHBXACDA-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 230000004075 alteration Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005347 demagnetization Effects 0.000 description 2
- 239000002355 dual-layer Substances 0.000 description 2
- 239000003302 ferromagnetic material Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 239000011787 zinc oxide Substances 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910017706 MgZn Inorganic materials 0.000 description 1
- 229910017708 MgZn2 Inorganic materials 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- GSWGDDYIUCWADU-UHFFFAOYSA-N aluminum magnesium oxygen(2-) Chemical compound [O--].[Mg++].[Al+3] GSWGDDYIUCWADU-UHFFFAOYSA-N 0.000 description 1
- 229910052810 boron oxide Inorganic materials 0.000 description 1
- ZDVYABSQRRRIOJ-UHFFFAOYSA-N boron;iron Chemical compound [Fe]#B ZDVYABSQRRRIOJ-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- VJQGOPNDIAJXEO-UHFFFAOYSA-N magnesium;oxoboron Chemical compound [Mg].O=[B] VJQGOPNDIAJXEO-UHFFFAOYSA-N 0.000 description 1
- PNHVEGMHOXTHMW-UHFFFAOYSA-N magnesium;zinc;oxygen(2-) Chemical compound [O-2].[O-2].[Mg+2].[Zn+2] PNHVEGMHOXTHMW-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- MZLGASXMSKOWSE-UHFFFAOYSA-N tantalum nitride Chemical compound [Ta]#N MZLGASXMSKOWSE-UHFFFAOYSA-N 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
- RNWHGQJWIACOKP-UHFFFAOYSA-N zinc;oxygen(2-) Chemical compound [O-2].[Zn+2] RNWHGQJWIACOKP-UHFFFAOYSA-N 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N50/00—Galvanomagnetic devices
- H10N50/10—Magnetoresistive devices
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N50/00—Galvanomagnetic devices
- H10N50/80—Constructional details
- H10N50/85—Materials of the active region
Landscapes
- Hall/Mr Elements (AREA)
- Mram Or Spin Memory Techniques (AREA)
Abstract
The application provides a magnetic tunnel knot structure and magnetic random access memory thereof, the ferromagnetic superlattice layer of the anti-ferromagnetic layer of magnetic tunnel knot structure combines with the reference layer, forms to have ultra-thin anti-ferromagnetic layer and reference layer bilayer structure, adjusts anti-ferromagnetic layer with the reference layer is in order to adjust it at the saturated magnetic moment of vertical direction the leakage magnetic field of free layer, it makes the magnetic tunnel knot have the regulation and control ability of the leakage magnetic field write current of relative preferred, is favorable to the promotion of magnetic tunnel knot unit at magnetism, electricity and yield and the miniaturization of device.
Description
Technical Field
The present invention relates to the field of memory technologies, and in particular, to a magnetic tunnel junction structure and a magnetic random access memory thereof.
Background
Magnetic Random Access Memory (MRAM) in a Magnetic Tunnel Junction (MTJ) having Perpendicular Anisotropy (PMA), as a free layer for storing information, there are two magnetization directions in the Perpendicular direction, that is: upward and downward, respectively corresponding to "0" and "1" or "1" and "0" in binary, in practical application, the magnetization direction of the free layer will remain unchanged when reading information or leaving empty; during writing, if a signal different from the existing state is input, the magnetization direction of the free layer will be flipped by one hundred and eighty degrees in the vertical direction. The ability of the mram to maintain the magnetization direction of the free Layer is called Data Retention (Data Retention) or Thermal Stability (Thermal Stability), and the requirement is different in different application situations, and for a typical Non-volatile Memory (NVM), the requirement of Data Retention is to retain Data for at least 10 years at 125 ℃, and the decrease of Data Retention or Thermal Stability is caused by external magnetic field flipping, Thermal disturbance, current disturbance or multiple read/write operations, so an Anti-ferromagnetic Layer (SyAF) superlattice is often used to achieve pinning of the Reference Layer (RL). Antiferromagnetic layer (SyAF) typically contains two superlattice ferromagnetic layers with strong perpendicular anisotropy, with a layer of ruthenium to achieve antiferromagnetic coupling of the two superlattice ferromagnetic layers. However, it is still difficult to effectively reduce the influence of the leakage magnetic field on the free layer.
Disclosure of Invention
In order to solve the above technical problems, an object of the present invention is to provide a magnetic tunnel junction structure and a magnetic random access memory thereof, which implement reference layer pinning, lattice inversion, ferromagnetic coupling enhancement and overall film layer structure thinning.
The purpose of the application and the technical problem to be solved are realized by adopting the following technical scheme.
According to the magnetic tunnel junction structure provided by the application, the structure from top to bottom comprises a Covering Layer (CL), a Free Layer (FL), a Barrier Layer (TB), a Reference Layer (RL), an Anti-ferromagnetic Layer (SyAF), a Seed Layer (SL), and a Buffer Layer (BL).
The Reference Layer (RL) has a structure of Fe, FeB, FeCoB or (Fe or FeB)/(CoB, CoFe, CoFeB, FeC, CoC or CoFeC); the antiferromagnetic layer structure is [ X/Pt ] n/Y/Z, [ X/Pd ] n/Y/Z, CoPt/Z, FePt/Z, NiPt/Z, CoFePt/Z, CoPd/Z, FePd/Z, NiPd/Z and CoFePt/Z; wherein n is more than or equal to 2 and less than or equal to 10; x, Y is selected from one or more of Co, Ni, Fe, CoFe, CoNi, NiFe, NiCo, CoNiFe, FeB, CoB, CoFeB, and the multilayer structure thereof, Z is a composite antiferromagnetic coupling layer, and the material thereof is selected from at least one of Cu, Ir, Rh, Cr, Re, V, Mo, Nb, Zr, W, Ta, Hf, Os, Tc, Mn, or the alloy thereof, or the bilayer structure thereof and the multilayer structure thereof. A composite antiferromagnetic coupling layer for coupling the reference layer and the antiferromagnetic layer, disposed on or combined in the antiferromagnetic layer, formed of a transition metal material capable of forming antiferromagnetic coupling; the antiferromagnetic layer is matched with the composite antiferromagnetic coupling layer to realize effective pinning of the reference layer, and the saturated magnetic moments of the antiferromagnetic layer and the reference layer in the vertical direction are adjusted to adjust the leakage magnetic field of the reference layer.
The technical problem solved by the application can be further realized by adopting the following technical measures.
In an embodiment of the present application, the total thickness of the antiferromagnetic layer is 0.5nm to 5.0 nm; the total thickness of the reference layer is 0.5 nm-1.5 nm.
In one embodiment of the present application, the composite antiferromagnetic coupling layer (Z) is formed of (Ir, Ru, Rh, Cu or Re)/(Cr, Mo, V, W, Ta, Nb, Hf, Zr or a combination thereof) in a left-right order representing a bottom-up structure, and has a total thickness selected as an antiferromagnetic coupling peak.
In an embodiment of the present application, Ir, Ru, Rh, Cu or Re enables antiferromagnetic coupling of the antiferromagnetic layer and the reference layer; cr, Mo, V, W, Ta, Nb, Hf, Zr, or a combination thereof effects lattice transformation from the antiferromagnetic layer having a face centered cubic FCC (111) structure to the reference layer having a body centered cubic BCC (001) structure.
In an embodiment of the present application, the composite antiferromagnetic coupling layer is made of a dual-layer structure of Ru/(Cr, CrMo, CrW, Mo, or W), where Ru is 0.3nm to 0.6nm thick, and Cr, CrMo, CrW, Mo, or W is 0.05nm to 0.5nm thick.
In an embodiment of the present application, the material of the composite antiferromagnetic coupling layer is an Ir/(Cr, CrMo, CrW, Mo, or W) dual-layer structure, where the thickness of Ir is 0.2nm to 0.6nm, and the thickness of Cr, CrMo, CrW, Mo, or W is 0.05nm to 0.5 nm.
In an embodiment of the present application, the antiferromagnetic layer has a perpendicular magnetic anisotropy and has a magnetic moment that is 1.1-1.8 times the magnetic moment of the reference layer.
In an embodiment of the application, the magnetic tunnel junction is subjected to an annealing process, the Magnetic Tunnel Junction (MTJ) structure unit after deposition being annealed at a temperature selected to be not less than 350 ℃, so that the Reference Layer (RL) and the Free Layer (FL) are transformed from an amorphous structure to a crystal structure of body-centered cubic BCC (001) under the templating action of a NaCl-type face-centered cubic FCC (001) barrier layer (TB).
Another object of the present invention is to provide a magnetic random access memory device, which includes the magnetic tunnel junction structure, a top electrode disposed above the magnetic tunnel junction structure, and a bottom electrode disposed below the magnetic tunnel junction structure.
The application has stronger leakage magnetic field (H) through an ultrathin magnetic tunnel junction structureStray) And the write current regulation and control capability are very beneficial to the improvement of the magnetism, the electricity and the yield of the magnetic random access memory and the further miniaturization of the device.
Drawings
FIG. 1 is a diagram illustrating an exemplary MRAM cell structure;
FIG. 2 is a diagram illustrating a magnetic memory cell structure of an embodiment of the magnetic random access memory of the present application;
fig. 3 shows the inter-layer Exchange Coupling (IEC) strength of different transition group metals according to an embodiment of the present invention.
Description of the symbols
10, a bottom electrode; 20, magnetic tunnel junction; 21, a buffer layer; 22, a seed layer; an antiferromagnetic layer 23; 24, a lattice partition layer; 25 reference layer; 26 a barrier layer; 27: a free layer; 28, a covering layer; and 30, a top electrode.
Detailed Description
Refer to the drawings wherein like reference numbers refer to like elements throughout. The following description is based on illustrated embodiments of the application and should not be taken as limiting the application with respect to other embodiments that are not detailed herein.
The following description of the various embodiments refers to the accompanying drawings, which illustrate specific embodiments that can be used to practice the present application. In the present application, directional terms such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", and the like are merely referring to the directions of the attached drawings. Accordingly, the directional terminology is used for purposes of illustration and understanding, and is in no way limiting.
The terms "first," "second," "third," and the like in the description and in the claims of the present application and in the above-described drawings, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the objects so described are interchangeable under appropriate circumstances. Furthermore, the terms "comprising" and "having," as well as variations thereof, such as, for example, are intended to cover non-exclusive inclusions.
The terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the concepts of the present application. Unless the context clearly dictates otherwise, expressions used in the singular form encompass expressions in the plural form. In the present specification, it will be understood that terms such as "including," "having," and "containing" are intended to specify the presence of the features, integers, steps, acts, or combinations thereof disclosed in the specification, and are not intended to preclude the presence or addition of one or more other features, integers, steps, acts, or combinations thereof. Like reference symbols in the various drawings indicate like elements.
The drawings and description are to be regarded as illustrative in nature, and not as restrictive. In the drawings, elements having similar structures are denoted by the same reference numerals. In addition, the size and thickness of each component shown in the drawings are arbitrarily illustrated for understanding and ease of description, but the present application is not limited thereto.
In the drawings, the range of configurations of devices, systems, components, circuits is exaggerated for clarity, understanding, and ease of description. It will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present.
In addition, in the description, unless explicitly described to the contrary, the word "comprise" will be understood to mean that the recited components are included, but not to exclude any other components. Further, in the specification, "on.
To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description is provided with reference to the accompanying drawings and specific embodiments for a magnetic tunnel junction structure and a magnetic random access memory thereof according to the present invention, and the specific structures, features and effects thereof are described in detail.
FIG. 1 is a diagram of an exemplary MRAM cell structure. The magnetic memory cell structure comprises a multi-layer structure formed by at least a bottom electrode 10, a magnetic tunnel junction 20 and a top electrode 30.
In some embodiments, the bottom electrode 10 is titanium Ti, titanium nitride TiN, tantalum Ta, tantalum nitride TaN, ruthenium Ru, tungsten W, tungsten nitride WN, or combinations thereof; the top electrode 30 is made of Ti, TiN, Ta, TaN, W, WN or their combination. The magnetic memory cell structure is typically implemented by Physical Vapor Deposition (PVD), and is typically planarized after deposition to achieve surface flatness for the magnetic tunnel junction 20.
In some embodiments, the magnetic tunnel junction 20 comprises a Capping Layer (CL)28, a Free Layer (FL)27, a Barrier Layer (TB) 26, a Reference Layer (RL)25, a lattice Breaking Layer (CBL) 24, an antiferromagnetic Anti-ferromagnetic Layer (SyAF)23, a Seed Layer (Seed Layer, SL)22, and a Buffer Layer (BL) 21.
As shown in fig. 1, the antiferromagnetic Layer 23 includes a first superlattice ferromagnetic Layer (the 1st ferromagnetic super-Layer, 1st FM-SL), an antiferromagnetic coupling Layer and a second superlattice ferromagnetic Layer (the 2nd ferromagnetic super-Layer, 2nd FM-SL) respectively disposed from bottom to top. A ferromagnetic superlattice layer formed of a transition metal having a face-centered crystal structure in combination with a ferromagnetic material; the antiferromagnetic coupling layer is arranged on the ferromagnetic superlattice layer and is formed by a metal material capable of forming antiferromagnetic coupling; the second ferromagnetic superlattice layer is arranged on the antiferromagnetic coupling layer and is formed by combining a transition metal with a face-centered crystal structure with a ferromagnetic material; wherein the antiferromagnetic coupling layer combines the ferromagnetic superlattice layer and the second ferromagnetic superlattice layer to perform antiferromagnetic coupling of the ferromagnetic superlattice layer, and the magnetic tunnel junction includes lattice conversion and strong ferromagnetic coupling between the antiferromagnetic layer and the reference layer.
In the magnetic tunnel junction 20 with perpendicular anisotropy, the free layer 27 functions to store information, possessing two magnetization directions in the perpendicular direction, namely: up and down, corresponding to "0" and "1" or "1" and "0" in the binary, respectively. The magnetization direction of the free layer 27 remains unchanged when information is read or left empty; during writing, if a signal of a different state from that of the existing state is input, the magnetization direction of the free layer 27 is inverted by 180 degrees in the vertical direction. The ability of the free layer 27 of a magnetic random access memory to maintain a constant magnetization direction is called Data Retention (Data Retention) or Thermal Stability (Thermal Stability). The data retention capacity can be calculated using the following formula:
wherein tau is the time when the magnetization vector is unchanged under the condition of thermal disturbance, tau0For the trial time (typically 1ns), E is the energy barrier of the free layer, kBBoltzmann constant, T is the operating temperature.
The Thermal Stability factor (Thermal Stability factor) can then be expressed as the following equation:
wherein, KeffIs the effective isotropic energy density of the free layer, V is the volume of the free layer, KVConstant of bulk anisotropy MsSaturation susceptibility of the free layer, demagnetization constant in the direction perpendicular to Nz, t thickness of the free layer, KiCD is the critical dimension of the magnetic random access memory (i.e., the diameter of the free layer), A, as the interfacial anisotropy constantsFor stiffness integral exchange constant, DnThe critical dimension of the free layer for different domain switching patterns. Experiments show that when the thickness of the free layer is thicker, the free layer shows in-plane anisotropy, and when the thickness of the free layer is thinner, the free layer shows vertical anisotropy, KVGenerally negligible, while the contribution of demagnetization energy to the perpendicular anisotropy is negative, so the perpendicular anisotropy comes entirely from the interfacial effect (K)i)。
In some embodiments, the thermal stability factor is also affected by the static magnetic Field, particularly the leakage magnetic Field (Stray Field) from the reference layer 25, in combination with the difference in the magnetization direction applied by the static magnetic Field on the free layer 27, to produce an enhancement or reduction effect. As shown in fig. 1, in order to reduce the influence of the leakage magnetic field on the Free Layer (FL)27, an antiferromagnetic layer (SyAF)23 having a strong perpendicular anisotropy (PMA) superlattice structure is typically added below the Reference Layer (RL) 25.
Due to the presence of the antiferromagnetic layer 23, the leakage magnetic field from the reference layer 25 and the antiferromagnetic layer 23 can be partially cancelled out, quantitatively, defining the total leakage magnetic field from the reference layer 25 and the antiferromagnetic layer 23 as HStray:
Wherein Hk effIs a perpendicular effective anisotropy field, Hk eff=2(Keff/(μ0Ms)). Further, defining the magnetization vector perpendicular to the free layer and upward as positive, the leakage magnetic field perpendicular to the free layer 27 upward is positive. Then the thermal stability factor for the magnetization vectors of the free layer 27 and the reference layer 25 in the case of parallel or antiparallel orientations, respectively, can be expressed as the following equation:
as the volume of the magnetic free layer 27 is reduced, the smaller the spin-polarized current to be injected for writing or switching operation. Critical current I for write operationc0The relationship between the compound and the thermal stability is strongly related, and can be expressed as the following formula:
wherein alpha is a damping constant,η is the spin polarizability, which is the approximate planck constant. Further, the critical current can be expressed as the following expressions when the magnetizations are parallel and antiparallel, respectively:
in this case, the critical current of the magnetic random access memory in the parallel state and the anti-parallel state can be further controlled by controlling the leakage magnetic Field (Stray Field). In addition, when etching the Magnetic Tunnel Junction (MTJ) cell array, in order to reduce the re-deposition of the conductive metal, the thickness of the Magnetic Tunnel Junction (MTJ) film layer also needs to be reduced.
In some embodiments, the magnetic tunnel junction 20, which is the core memory cell of the magnetic random access memory, must also be compatible with CMOS processes and must be able to withstand long term annealing at 400 ℃.
Fig. 2 is a schematic diagram of a magnetic memory cell structure of the magnetic random access memory of the present application, and fig. 3 is an exemplary illustration of the inter-layer Exchange Coupling (IEC) strength of different transition group metals of the present application, please refer to fig. 1 for understanding. The magnetic tunnel junction structure provided by the present application includes, from top to bottom, a capping layer 28, a free layer 27, a barrier layer 26, a reference layer 25, an antiferromagnetic layer 23, a seed layer 22, and a buffer layer 21.
The structure of the reference layer is Fe, FeB, FeCoB or (Fe or FeB)/(CoB, CoFe, CoFeB, FeC, CoC or CoFeC); the antiferromagnetic layer structure is [ X/Pt ]]n/Y/Z,[X/Pd]nY/Z, CoPt/Z, FePt/Z, NiPt/Z, CoFePt/Z, CoPd/Z, FePd/Z, NiPd/Z, CoFePt/Z; wherein n is more than or equal to 2 and less than or equal to 10; x, Y is selected from one or more of Co, Ni, Fe, CoFe, CoNi, NiFe, NiCo, CoNiFe, FeB, CoB, CoFeB, and the multilayer structure thereof, Z is a composite antiferromagnetic coupling layer, and the material thereof is selected from at least one of Cu, Ir, Rh, Cr, Re, V, Mo, Nb, Zr, W, Ta, Hf, Os, Tc, Mn, or the alloy thereof, or the bilayer structure thereof and the multilayer structure thereof. A composite antiferromagnetic coupling layer for coupling the reference layer and the antiferromagnetic layer, disposed on or combined in the antiferromagnetic layer, formed of a transition metal material capable of forming antiferromagnetic coupling; the antiferromagnetic layer is matched with the composite antiferromagnetic coupling layer to realize effective pinning of the reference layer, and the saturated magnetic moments of the antiferromagnetic layer and the reference layer in the vertical direction are adjusted to adjust the leakage magnetic field of the reference layer.
In an embodiment of the present application, the total thickness of the antiferromagnetic layer is 0.5nm to 5.0 nm; the total thickness of the reference layer is 0.5 nm-1.5 nm.
In an embodiment of the present application, the composite antiferromagnetic coupling layer (Z) is formed of (Ir, Ru, Rh, Cu or Re)/(Cr, Mo, V, W, Ta, Nb, Hf, Zr or a combination thereof) in a left-right order representing a bottom-up structure, and has a total thickness selected as an antiferromagnetic coupling peak, Ir, Ru, Rh, Cu or Re being used to realize antiferromagnetic coupling of the antiferromagnetic layer and the reference layer; cr, Mo, V, W, Ta, Nb, Hf, Zr, or combinations thereof are used to achieve lattice transformation from the antiferromagnetic layer having a face centered cubic FCC (111) structure to the reference layer having a body centered cubic BCC (001) structure.
In some embodiments, as shown in fig. 3, the layer structure of Cr, Mo, V, W, Ta, Nb, Hf, Zr or their combination has an absorption capability of B or C, and at the same time, an additional RKKY antiferromagnetic Coupling can be provided due to the presence of the layer, in which case, the RKKY antiferromagnetic Coupling (IEC) energy density is not damaged compared to the single layer structure.
In some embodiments, the material of the composite antiferromagnetic coupling layer is a Ru/(Cr, CrMo, CrW, Mo or W) double-layer structure, the thickness of Ru is 0.3 nm-0.6 nm, and the thickness of Cr, CrMo, CrW, Mo or W is 0.05 nm-0.5 nm.
In some embodiments, the material of the composite antiferromagnetic coupling layer is an Ir/(Cr, CrMo, CrW, Mo or W) double-layer structure, wherein the thickness of Ir is 0.2nm to 0.6nm, and the thickness of Cr, CrMo, CrW, Mo or W is 0.05nm to 0.5 nm.
In some embodiments, the Bottom Electrode (BE)10 is made of Ti, TiN, Ta, TaN, Ru, W, WN or a combination thereof, and is typically implemented by Physical Vapor Deposition (PVD), and is typically planarized after deposition to achieve surface flatness for fabricating the magnetic tunnel junction; the Top Electrode (TE)30 is made of Ti, TiN, Ta, TaN, W, WN or their combination.
In some embodiments, the Buffer Layer (BL)21 is generally composed of Ta, Ti, TiN, TaN, W, WN, Ru, Pt, O, N, CoB, FeB, CoFeB, or combinations thereof. The Seed Layer (SL)22 generally comprises Pt, Ru, Cr, etc. having an FCC (111) crystal structure for optimizing the crystal structure of the subsequent synthetic ferromagnetic layer (SyAF) 23.
In some embodiments, the barrier layer 26 of the magnetic tunnel junction 20 is formed of a non-magnetic metal oxide having a thickness between 0.6nm and 1.5nm, the non-magnetic metal oxide including magnesium oxide MgO, magnesium zinc oxide MgZn2O4Zinc oxide ZnO and aluminum oxide Al2O3MgN, Mg boron oxide, Mg3B2O6Or Mg3Al2O6. Preferably, magnesium oxide MgO may be used.
In one embodiment of the present application, the free layer 27 of the magnetic tunnel junction 20 has variable magnetic polarization, and the material of the free layer 27 is generally composed of Fe, Co, Ni, CoFe, CoB, FeB, CoFeB, W, Mg, Zr, Al, Zn, Nb, Mo, Ta, Hf, Zr, V, Cr, Mg, Ti or Ru. Further, a single layer structure selected from cobalt boride CoB, iron boride FeB, cobalt iron boron CoFeB, or a double layer structure of cobalt boride CoFe/cobalt iron boron CoFeB, or iron Fe/cobalt iron boron CoFeB/(tungsten W, molybdenum Mo, vanadium V, niobium Nb, chromium Cr, hafnium Hf, titanium Ti, zirconium Zr, tantalum Ta, scandium Sc, yttrium Y, zinc Zn, ruthenium Ru, osmium, rhodium Rh, iridium Ir, palladium Pd and/or platinum Pt)/cobalt iron boron CoFeB, cobalt iron boron CoFeB/(tungsten W, molybdenum Mo, vanadium V, niobium Nb, chromium Cr, hafnium Hf, titanium Ti, zirconium Zr, tantalum Ta, scandium Sc, yttrium Y, zinc Zn, ruthenium Ru, osmium Os, rhodium Rh, iridium Ir, palladium Pd and/or platinum Pt)/cobalt iron boron, or a triple layer structure of iron/cobalt iron boron/(tungsten W, molybdenum Mo, vanadium V, niobium V, niobium, ruthenium, hafnium Zr, tantalum Ta, scandium Pd and/or platinum Pt)/cobalt iron boron may be used, A four-layer structure of yttrium Y, zinc Zn, ruthenium Ru, osmium Os, rhodium Rh, iridium Ir, palladium Pd and/or platinum Pt)/CoFeB, cobalt ferrite/CoFeB/(tungsten W, molybdenum Mo, vanadium V, niobium Nb, chromium Cr, hafnium Hf, titanium Ti, zirconium Zr, tantalum Ta, scandium Sc, yttrium Y, zinc Zn, ruthenium Ru, osmium Os, rhodium Rh, iridium Ir, palladium Pd and/or platinum Pt)/CoFeB; the thickness of the free layer 27 is between 1.0 nm and 3.0 nm.
In one embodiment of the present application, after the deposition of the Free Layer (FL)27, a Capping Layer (CL)28 is again deposited, the material of the capping layer 28 being selected from (Mg, MgO, MgZn, magnesium oxide)2O4Magnesium boron oxide Mg3B2O6Or magnesium aluminum oxide Mg3Al2O6One of the two layers is a double-layer structure of (one of) tungsten W, molybdenum Mo, magnesium Mg, niobium Nb, ruthenium Ru, hafnium Hf, vanadium V, chromium Cr and platinum Pt), or a three-layer structure of magnesium oxide MgO/(one of tungsten W, molybdenum Mo and hafnium Hf)/ruthenium Ru, or magnesium oxide/platinum/(one of tungsten, molybdenum and hafnium Hf)Or one of hafnium)/ruthenium. In some embodiments, the selection of magnesium oxide (MgO) can provide a source of additional interfacial anisotropy for the Free Layer (FL)26, thereby increasing thermal stability.
In an embodiment of the present application, the antiferromagnetic layer has a perpendicular magnetic anisotropy and has a magnetic moment that is 1.1-1.8 times the magnetic moment of the reference layer.
In one embodiment of the present application, an annealing process is performed on the magnetic tunnel junction 20, which is selected to anneal the Magnetic Tunnel Junction (MTJ) structure unit after deposition at no less than 350 ℃, so that the reference layer 25 and the free layer 27 are transformed from an amorphous structure to a body-centered-cubic stacked crystal structure under the templating effect of the sodium chloride (NaCl) type face-centered-cubic crystal structure barrier layer 26.
Referring again to fig. 2, in an embodiment of the present application, a magnetic random access memory includes a plurality of memory cells, including any of the aforementioned magnetic tunnel junction 20 structures, a top electrode 30 disposed above the magnetic tunnel junction 20 structure, and a bottom electrode 10 disposed below the magnetic tunnel junction 20 structure.
In one embodiment of the present application, the bottom electrode 10, the magnetic tunnel junction 20, and the top electrode 30 are all formed by a physical vapor deposition process.
The application has stronger leakage magnetic field (H) through an ultrathin magnetic tunnel junction structureStray) And the write current regulation and control capability are very beneficial to the improvement of the magnetism, the electricity and the yield of the magnetic random access memory and the further miniaturization of the device.
The terms "in one embodiment of the present application" and "in various embodiments" are used repeatedly. This phrase generally does not refer to the same embodiment; it may also refer to the same embodiment. The terms "comprising," "having," and "including" are synonymous, unless the context dictates otherwise.
Although the present application has been described with reference to specific embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application, and all changes, substitutions and alterations that fall within the spirit and scope of the application are to be understood as being covered by the following claims.
Claims (9)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010136585.5A CN113346007A (en) | 2020-03-02 | 2020-03-02 | Magnetic tunnel junction structure and magnetic random access memory thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010136585.5A CN113346007A (en) | 2020-03-02 | 2020-03-02 | Magnetic tunnel junction structure and magnetic random access memory thereof |
Publications (1)
Publication Number | Publication Date |
---|---|
CN113346007A true CN113346007A (en) | 2021-09-03 |
Family
ID=77467312
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202010136585.5A Pending CN113346007A (en) | 2020-03-02 | 2020-03-02 | Magnetic tunnel junction structure and magnetic random access memory thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113346007A (en) |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20020018919A1 (en) * | 2000-04-12 | 2002-02-14 | Masamichi Saito | Exchange coupling film and electroresistive sensor using the same |
US20030203241A1 (en) * | 2002-04-23 | 2003-10-30 | Alps Electric Co., Ltd. | Exchange coupling film, magnetic detecting element using the exchange coupling film, and method of making same |
US20080225583A1 (en) * | 2007-03-13 | 2008-09-18 | Magic Technologies, Inc. | Spin transfer MRAM device with novel magnetic free layer |
US20140021426A1 (en) * | 2012-07-17 | 2014-01-23 | Yun-Jae Lee | Magnetic device and method of manufacturing the same |
US20150162525A1 (en) * | 2013-12-09 | 2015-06-11 | Sang Hwan Park | Memory devices and methods of manufacturing the same |
US20150255135A1 (en) * | 2014-03-05 | 2015-09-10 | Agency For Science, Technology And Research | Magnetoelectric device, method for forming a magnetoelectric device, and writing method for a magnetoelectric device |
US20190019943A1 (en) * | 2018-07-26 | 2019-01-17 | Xi'an Jiaotong University | Novel magnetic tunnel junction device and magnetic random access memory |
US20190027169A1 (en) * | 2017-07-21 | 2019-01-24 | Applied Materials, Inc. | Magnetic tunnel junctions suitable for high temperature thermal processing |
CN110676288A (en) * | 2019-10-21 | 2020-01-10 | 上海磁宇信息科技有限公司 | Magnetic tunnel junction structure and magnetic random access memory |
-
2020
- 2020-03-02 CN CN202010136585.5A patent/CN113346007A/en active Pending
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20020018919A1 (en) * | 2000-04-12 | 2002-02-14 | Masamichi Saito | Exchange coupling film and electroresistive sensor using the same |
US20030203241A1 (en) * | 2002-04-23 | 2003-10-30 | Alps Electric Co., Ltd. | Exchange coupling film, magnetic detecting element using the exchange coupling film, and method of making same |
US20080225583A1 (en) * | 2007-03-13 | 2008-09-18 | Magic Technologies, Inc. | Spin transfer MRAM device with novel magnetic free layer |
US20140021426A1 (en) * | 2012-07-17 | 2014-01-23 | Yun-Jae Lee | Magnetic device and method of manufacturing the same |
US20150162525A1 (en) * | 2013-12-09 | 2015-06-11 | Sang Hwan Park | Memory devices and methods of manufacturing the same |
US20150255135A1 (en) * | 2014-03-05 | 2015-09-10 | Agency For Science, Technology And Research | Magnetoelectric device, method for forming a magnetoelectric device, and writing method for a magnetoelectric device |
US20190027169A1 (en) * | 2017-07-21 | 2019-01-24 | Applied Materials, Inc. | Magnetic tunnel junctions suitable for high temperature thermal processing |
US20190019943A1 (en) * | 2018-07-26 | 2019-01-17 | Xi'an Jiaotong University | Novel magnetic tunnel junction device and magnetic random access memory |
CN110676288A (en) * | 2019-10-21 | 2020-01-10 | 上海磁宇信息科技有限公司 | Magnetic tunnel junction structure and magnetic random access memory |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20130059168A1 (en) | Magnetoresistance Device | |
CN111613720B (en) | Magnetic random access memory storage unit and magnetic random access memory | |
CN110676288A (en) | Magnetic tunnel junction structure and magnetic random access memory | |
JP6567272B2 (en) | Magnetic multilayer stack | |
CN112736192B (en) | Magnetic tunnel junction structure with double barrier layers and magnetic random access memory | |
US20130052483A1 (en) | Magnetoresistance Device | |
CN112864306A (en) | Magnetic tunnel junction structure with symmetrical double barrier layers and magnetic random access memory | |
CN113346007A (en) | Magnetic tunnel junction structure and magnetic random access memory thereof | |
CN112736191A (en) | Magnetic tunnel junction structure with symmetrical structure and magnetic random access memory | |
CN112635656A (en) | Magnetic tunnel junction structure and magnetic random access memory | |
CN113140670A (en) | Magnetic tunnel junction vertical antiferromagnetic layer and random access memory | |
CN112652707B (en) | Magnetic tunnel junction structure and magnetic random access memory thereof | |
CN112635650B (en) | Magnetic tunnel junction structure and magnetic memory thereof | |
CN112635649A (en) | Magnetic tunnel junction structure and magnetic random access memory | |
CN112310271B (en) | Magnetic tunnel junction structure of magnetic random access memory | |
CN112635654A (en) | Magnetic tunnel junction structure and magnetic random access memory | |
CN112635651A (en) | Magnetic tunnel junction structure and magnetic random access memory | |
CN113346006B (en) | Magnetic tunnel junction structure and magnetic random access memory thereof | |
CN111864057A (en) | Magnetic random access device and magnetic tunnel junction storage unit | |
CN112652702B (en) | Magnetic tunnel junction structure of magnetic random access memory | |
CN112652705B (en) | Magnetic tunnel junction structure and magnetic random access memory thereof | |
CN113013325B (en) | Magnetic tunnel junction unit with leakage magnetic field balance layer and magnetic random access memory | |
CN112928201B (en) | Magnetic tunnel junction structure of synthetic anti-iron layer with lattice transmission function | |
CN112864313B (en) | Magnetic tunnel junction structure of magnetic random access memory | |
CN112802959A (en) | Magnetic tunnel junction structure and magnetic random access memory |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210903 |
|
RJ01 | Rejection of invention patent application after publication |