CN118742190A - Magnetic compensation MTJ device, manufacturing method thereof and MRAM device - Google Patents
Magnetic compensation MTJ device, manufacturing method thereof and MRAM device Download PDFInfo
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- 239000002131 composite material Substances 0.000 claims description 16
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 15
- 230000008878 coupling Effects 0.000 claims description 14
- 238000010168 coupling process Methods 0.000 claims description 14
- 238000005859 coupling reaction Methods 0.000 claims description 14
- 229910017052 cobalt Inorganic materials 0.000 claims description 13
- 239000010941 cobalt Substances 0.000 claims description 13
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 13
- 230000005290 antiferromagnetic effect Effects 0.000 claims description 12
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 12
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 11
- 230000008859 change Effects 0.000 claims description 10
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 8
- 239000000395 magnesium oxide Substances 0.000 claims description 8
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 7
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims description 7
- 230000001419 dependent effect Effects 0.000 claims description 7
- 229910052763 palladium Inorganic materials 0.000 claims description 7
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- FQMNUIZEFUVPNU-UHFFFAOYSA-N cobalt iron Chemical compound [Fe].[Co].[Co] FQMNUIZEFUVPNU-UHFFFAOYSA-N 0.000 claims description 6
- 229910052759 nickel Inorganic materials 0.000 claims description 6
- 229910052697 platinum Inorganic materials 0.000 claims description 6
- 229910052707 ruthenium Inorganic materials 0.000 claims description 6
- QDWJUBJKEHXSMT-UHFFFAOYSA-N boranylidynenickel Chemical compound [Ni]#B QDWJUBJKEHXSMT-UHFFFAOYSA-N 0.000 claims description 4
- 229910052741 iridium Inorganic materials 0.000 claims description 4
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 4
- BMPDGKPFUQVSBL-UHFFFAOYSA-N [Fe].[Co].[Gd] Chemical compound [Fe].[Co].[Gd] BMPDGKPFUQVSBL-UHFFFAOYSA-N 0.000 claims description 3
- FOPBMNGISYSNED-UHFFFAOYSA-N [Fe].[Co].[Tb] Chemical compound [Fe].[Co].[Tb] FOPBMNGISYSNED-UHFFFAOYSA-N 0.000 claims description 3
- WBWJXRJARNTNBL-UHFFFAOYSA-N [Fe].[Cr].[Co] Chemical compound [Fe].[Cr].[Co] WBWJXRJARNTNBL-UHFFFAOYSA-N 0.000 claims description 3
- ZDVYABSQRRRIOJ-UHFFFAOYSA-N boron;iron Chemical compound [Fe]#B ZDVYABSQRRRIOJ-UHFFFAOYSA-N 0.000 claims description 3
- QNWDQRWHBHBLSM-UHFFFAOYSA-N cobalt iron platinum Chemical compound [Fe].[Co].[Pt] QNWDQRWHBHBLSM-UHFFFAOYSA-N 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- UGKDIUIOSMUOAW-UHFFFAOYSA-N iron nickel Chemical compound [Fe].[Ni] UGKDIUIOSMUOAW-UHFFFAOYSA-N 0.000 claims description 3
- WRSVIZQEENMKOC-UHFFFAOYSA-N [B].[Co].[Co].[Co] Chemical compound [B].[Co].[Co].[Co] WRSVIZQEENMKOC-UHFFFAOYSA-N 0.000 claims description 2
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- 125000006850 spacer group Chemical group 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910003321 CoFe Inorganic materials 0.000 description 1
- 229910019236 CoFeB Inorganic materials 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
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- HZEIHKAVLOJHDG-UHFFFAOYSA-N boranylidynecobalt Chemical compound [Co]#B HZEIHKAVLOJHDG-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B61/00—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
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- 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
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N52/00—Hall-effect devices
- H10N52/01—Manufacture or treatment
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N52/00—Hall-effect devices
- H10N52/80—Constructional details
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N52/00—Hall-effect devices
- H10N52/80—Constructional details
- H10N52/85—Magnetic active materials
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- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Mram Or Spin Memory Techniques (AREA)
- Hall/Mr Elements (AREA)
Abstract
The invention discloses a magnetic compensation Magnetic Tunnel Junction (MTJ) device, a manufacturing method thereof and Magnetic Random Access Memory (MRAM) equipment, which relate to the field of magnetic memories and comprise an MTJ unit, an isolation layer and a magnetic compensation layer which are sequentially stacked; the MTJ unit comprises a free layer, a barrier layer and an SAF fixed layer which are stacked; under the same temperature in a preset temperature range, the net residual magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the ratio of the net magnetization intensity of the magnetic compensation layer corresponding to the magnetic compensation layer do not exceed a first given range, and the direction of the net magnetization intensity of the magnetic compensation layer is opposite to that of the net magnetization intensity of the SAF fixed layer; the magnetic switching field of the magnetic compensation layer is greater than the magnetic switching field of the free layer. The invention ensures that the leakage magnetic field generated by the magnetic compensation layer at the corresponding position of the free layer and the leakage magnetic field generated by the fixed layer are mutually offset at the same temperature within a certain range, thereby ensuring the balance of the data holding capacity of the MTJ device.
Description
Technical Field
The present invention relates to the field of magnetic memories, and in particular, to a magnetic compensation MTJ device, a method of manufacturing the same, and an MRAM device.
Background
Magnetic Random Access Memory (MRAM) is composed of an array of Magnetic Tunnel Junctions (MTJ) whose core structure includes a free layer, a barrier layer, and a fixed layer. Wherein the free layer and the fixed layer are magnetic multilayer films, and the barrier layer is a very thin insulating layer, typically less than 2nm thick. When the MTJ works normally, the magnetization direction of the fixed layer is unchanged, the magnetization direction of the free layer can be changed by an externally applied magnetic field or an input current, and the resistance value of the MTJ is determined by the relative magnetization directions of the free layer and the fixed layer. When the magnetization directions of the free layer and the fixed layer are parallel, the MTJ is in a low resistance state; when the magnetization directions of the free layer and the fixed layer are antiparallel, the MTJ assumes a high resistance state. The MTJ device enables recording of data information based on the high and low resistance states of the MTJ.
To reduce the effect of the pinned layer leakage field on the free layer, an artificial antiferromagnetic (SAF) based pinned layer is used. The leakage magnetic fields of the magnetic layers in the free layer in the fixed layer of the artificial antiferromagnetic structure can cancel each other, so that the data holding difficulty of the free layer in two magnetization states is nearly consistent, and the balance of the data holding capacities of the MTJ device in different resistance states is ensured. However, in the conventional MTJ thin film, in order to meet specific performance requirements, such as stronger Perpendicular Magnetic Anisotropy (PMA), higher magnetoresistance (TMR), and the like, materials used for the pinned layer and the reference layer are different, the magnetization of the MTJ thin film has different temperature change responses, and the MTJ device has a complex environment in the actual use process, and the environment temperature is changeable, so that the leakage magnetic fields of the SAF-based fixed layer at the free layer cannot cancel each other along with the temperature change, in other words, the data retention capability of the high-low resistance state also differs greatly at different temperatures, which is unfavorable for the reliability and yield of the MTJ device.
Therefore, how to ensure the balance of the data holding capability of the MTJ device in different resistance states at different temperatures and improve the reliability of the MTJ device becomes a problem to be solved by those skilled in the art.
Disclosure of Invention
The invention aims to provide a magnetic compensation MTJ device, a manufacturing method thereof and an MRAM device, which are used for solving the problem that the data holding capacity of high and low resistance states of the MTJ device in the prior art is larger in difference at different temperatures.
In order to solve the technical problems, the invention provides a magnetic compensation MTJ device, which comprises an MTJ unit, an isolation layer and a magnetic compensation layer which are sequentially stacked;
the MTJ unit comprises a free layer, a barrier layer and an SAF fixed layer which are stacked;
Under the same temperature in a preset temperature range, the net residual magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the ratio of the net magnetization intensity of the magnetic compensation layer corresponding to the magnetic compensation layer do not exceed a first given range, and the direction of the net magnetization intensity of the magnetic compensation layer is opposite to that of the net magnetization intensity of the SAF fixed layer;
the magnetic switching field of the magnetic compensation layer is greater than the magnetic switching field of the free layer.
Optionally, in the magnetic compensation MTJ device, the magnetic compensation layer includes a first compensation sublayer, a reverse coupling layer, and a second compensation sublayer that are sequentially stacked.
Optionally, in the magnetic compensation MTJ device, the first compensation sublayer and/or the second compensation sublayer are composite layers.
Optionally, in the magnetic compensation MTJ device, the composite layer includes an anisotropic auxiliary layer and a magnetic layer that are stacked.
Optionally, in the magnetic compensation MTJ device, the anisotropic auxiliary layer includes at least one of a magnesium oxide layer or a cobalt layer;
When the anisotropic auxiliary layer is a magnesium oxide layer, the magnetic layer comprises at least one of a cobalt layer, an iron layer, a nickel layer, a cobalt boride layer, an iron boride layer, a nickel boride layer, a cobalt iron layer, an iron nickel layer, a cobalt iron boron layer, a cobalt iron platinum layer, a cobalt iron palladium layer, a cobalt iron terbium layer, a cobalt iron chromium layer and a cobalt iron gadolinium layer;
When the anisotropic auxiliary layer is a cobalt layer, the magnetic layer includes at least one of a platinum layer, a palladium layer, and a nickel layer.
Optionally, in the magnetic compensation MTJ device, the reverse coupling layer includes at least one of an iridium layer and a ruthenium layer.
Optionally, in the magnetic compensation MTJ device, the first given range is 0.8 to 1.2, including an end point value.
Optionally, in the magnetic compensation MTJ device, an antiferromagnetic pinning layer is further included;
the antiferromagnetic pinning layer is disposed on a surface of the magnetic compensation layer remote from the isolation layer.
An MRAM device comprising a magnetically compensated MTJ device as claimed in any one of the above.
A method of fabricating a magnetically compensated MTJ device, comprising:
acquiring data of an MTJ unit to be processed; the MTJ unit to be processed corresponding to the data of the MTJ unit to be processed comprises a free layer, a barrier layer and an SAF fixed layer which are arranged in a stacked manner;
Determining reference temperature change magnetization data according to the MTJ unit data to be processed; the reference temperature-dependent magnetization data refer to data of the corresponding relationship between the net magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the temperature within a preset temperature range;
Determining magnetic compensation layer data according to the reference temperature change magnetization data, so that the ratio of the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer to the net magnetization of the SAF fixed layer at the same temperature within a preset temperature range does not exceed a first given range, the net magnetization of the magnetic compensation layer and the net magnetization of the SAF fixed layer are opposite in direction, and the magnetic inversion field of the magnetic compensation layer is larger than the magnetic inversion field of the free layer;
Setting the MTJ unit to be processed according to the data of the MTJ unit to be processed, setting the magnetic compensation layer according to the data of the magnetic compensation layer, and setting an isolation layer between the MTJ unit to be processed and the magnetic compensation layer to obtain a finished MTJ device.
The magnetic compensation MTJ device provided by the invention comprises an MTJ unit, an isolation layer and a magnetic compensation layer which are sequentially stacked; the MTJ unit comprises a free layer, a barrier layer and an SAF fixed layer which are stacked; under the same temperature in a preset temperature range, the net residual magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the ratio of the net magnetization intensity of the magnetic compensation layer corresponding to the magnetic compensation layer do not exceed a first given range, and the direction of the net magnetization intensity of the magnetic compensation layer is opposite to that of the net magnetization intensity of the SAF fixed layer; the magnetic switching field of the magnetic compensation layer is greater than the magnetic switching field of the free layer.
The magnetic compensation layer is additionally arranged on one side of the MTJ unit, the net residual magnetization intensity of the magnetic compensation layer is similar to that of the SAF fixed layer at the same temperature, but the magnetization directions are opposite, so that the leakage magnetic field generated by the magnetic compensation layer and the leakage magnetic field generated by the fixed layer are mutually offset at the same temperature within a certain range at the corresponding position of the free layer, the balance of the data holding capability of the MTJ device in different resistance states at different temperatures is further ensured, and the reliability and the yield of the MTJ device are improved. The invention also provides a manufacturing method of the magnetic compensation MTJ device and an MRAM device.
Drawings
For a clearer description of embodiments of the invention or of the prior art, the drawings that are used in the description of the embodiments or of the prior art will be briefly described, it being apparent that the drawings in the description below are only some embodiments of the invention, and that other drawings can be obtained from them without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a magnetic compensation MTJ device according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a magnetic compensation MTJ device according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of another embodiment of a magnetic compensation MTJ device provided by the present invention;
FIG. 4 is a schematic diagram of another embodiment of a magnetic compensation MTJ device according to the present invention;
FIG. 5 is a schematic diagram of a structure of a further embodiment of a magnetic compensation MTJ device provided by the present invention;
fig. 6 is a schematic flow chart of a method for manufacturing a magnetic compensation MTJ device according to an embodiment of the present invention.
Detailed Description
SAF structure is Co/Pt, co/Pd or Co/Ni multilayer film, and antiferromagnetic coupling is generated inside the SAF structure through the coupling layer, so that the magnetic leakage fields of the magnetic layers of the fixed layer cancel each other at the free layer. The leakage magnetic field cancellation condition can be characterized by an offset field (H offset). The value of H offset has a correlation to the data retention time, bit failure, etc. of the MTJ device. If H offset is other than 0, the free layer magnetic moment will always be in a leakage field other than 0, resulting in a MTJ device that tends to maintain a particular resistance state (high resistance state or low resistance state) that has a corresponding data retention time that is higher than the other resistance state. Therefore, the MTJ device of the present invention can be considered as having a value of H offset approaching at different temperatures, when the leakage magnetic field generated by the magnetic compensation layer 30 at the position corresponding to the free layer and the leakage magnetic field generated by the fixed layer cancel each other at the same temperature within a certain range.
In order to better understand the aspects of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The core of the present invention is to provide a magnetic compensation MTJ device, a schematic structural diagram of one embodiment of which is shown in fig. 1, which is referred to as embodiment one, and includes an MTJ unit, an isolation layer 20, and a magnetic compensation layer 30 that are sequentially stacked;
the MTJ cell includes a free layer 11, a barrier layer 12, and a SAF fixed layer 13 stacked;
At the same temperature within the preset temperature range, the ratio of the net magnetization of the SAF fixed layer corresponding to the SAF fixed layer 13 to the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer 30 does not exceed a first given range, and the direction of the net magnetization of the magnetic compensation layer is opposite to that of the net magnetization of the SAF fixed layer;
the magnetic switching field of the magnetic compensation layer 30 is greater than the magnetic switching field of the free layer 11.
Of course, in actual production, the net magnetization of the magnetic compensation layer and the net magnetization of the SAF fixed layer at the same temperature should be guaranteed as much as possible, so that the leakage magnetic fields generated by the magnetic compensation layer 30 and the SAF fixed layer 13 at the corresponding positions of the free layer 11 cancel each other.
In the present invention, the net magnetization of the magnetic compensation layer refers to the leakage magnetic field generated by the compensation layer at the position corresponding to the free layer, and similarly, the net magnetization of the SAF fixed layer refers to the leakage magnetic field generated by the SAF fixed layer 13 at the position corresponding to the free layer.
It should be noted that, in the present invention, the ratio of the net magnetization of the SAF fixed layer to the ratio of the net magnetization of the magnetic compensation layer to the index value of the ratio is not related to the description of the direction by the ratio, and of course, it is also possible to provide that a certain direction is a positive direction, and then the ratio of the net magnetization to the index value of the ratio is necessarily smaller than 0. The adjustment of the net magnetization of the magnetic compensation layer can be achieved by adjusting the structure, the size, the material, etc. of the magnetic compensation layer 30 through means of combining analog calculation with actual production inspection, etc., and will not be described in detail herein.
The spacer layer 20 comprises one or more of a non-magnetic metal, alloy, oxide, nitride, and may be a single layer film or a multi-layer film for eliminating magnetic coupling between the free layer 11 or the fixed layer and the magnetic compensation layer 30.
It is readily apparent that the magnetic switching field of the magnetic compensation layer 30 is greater than the magnetic switching field of the free layer 11, otherwise the free layer 11 remains stable and is not switched, while the magnetic compensation layer 30 is switched. Therefore, the magnetic inversion field of the magnetic compensation layer 30 is made larger than that of the free layer 11, in order to further improve the operational stability and reliability of the MTJ device.
As a preferred embodiment, the magnetic compensation layer 30 includes a first compensation sub-layer 31, a reverse coupling layer 33, and a second compensation sub-layer 32, which are sequentially stacked.
The magnetic compensation layer 30 in the present invention may be disposed on either side of the MTJ cell, i.e., on the SAF fixed layer 13 side (fig. 1) or on the free layer 11 side (fig. 3).
As a specific embodiment, the magnetic compensation layer 30 and/or the isolation layer 20 may be disposed at a position other than the MTJ film (including only a part of the structure in the MTJ device, see fig. 4) of the MRAM device, for example, a position of the bottom electrode 002 or the top electrode 001 contacting the MTJ film, which may also achieve a similar effect, and the present invention is not limited thereto.
Because the first compensation sub-layer 31 and the second compensation sub-layer 32 are connected by the reverse coupling layer 33, it is easy to know that the magnetization directions of the first compensation sub-layer 31 and the second compensation sub-layer 32 are opposite, please refer to fig. 1 (the SAF fixing layer 13 in fig. 1 includes the reference layer 13A, the coupling layer 13B and the pinning layer 13C), and the magnetic compensation layer 30 is formed by two magnetic layers with opposite directions, so that the magnetic inversion field of the magnetic compensation layer 30 can be greatly improved, and the magnetic compensation layer 30 is less prone to be inverted under the action of external environment (high temperature, complex electromagnetic environment, etc.), thereby improving the working stability and reliability of the device. Of course, the magnetic compensation layer 30 may be a single layer film, or other forms of film layers, and the invention is not limited herein.
Specifically, the reverse coupling layer 33 includes at least one of an iridium (Ir) layer and a ruthenium (Ru) layer, and the two material layers are material layers with mature process and good coupling property, and of course, other material layers may be selected according to practical situations. The back coupling layer 33 may be a single layer or a multi-layer composite, and of course, the back coupling layer 33 may be a mixture layer, such as a mixture layer made of iridium metal and ruthenium metal.
Further, the first compensation sub-layer 31 and/or the second compensation sub-layer 32 are composite layers.
Of course, the ratio of the net magnetization of the magnetic compensation layer to the net magnetization of the SAF fixed layer is closer to 1, the balance effect of the data holding capability of the MTJ device in different resistance states is better, while in the preferred embodiment, the first compensation sublayer 31 and/or the second compensation sublayer 32 are designed in the form of a composite layer, so that the adjustment precision of the strength and direction of the first compensation sublayer 31 and/or the second compensation sublayer 32 is higher, and the balance of the data holding capability of the MTJ device in different resistance states is better improved by adjusting the leakage magnetic field strength of the SAF fixed layer 13 in the corresponding position of the free layer 11.
Still further, the composite layer includes an anisotropic auxiliary layer and a magnetic layer that are stacked.
In the preferred embodiment, the first compensation sub-layer 31 and/or the second compensation sub-layer 32 are composite layers including the anisotropic auxiliary layer and the magnetic layer, and the anisotropic auxiliary layer is a layer that cooperates with the corresponding magnetic layer to improve the perpendicular magnetic anisotropy of the corresponding compensation sub-layer, so that the improvement of the perpendicular magnetic anisotropy can further improve the working stability of the MTJ device.
And in particular, the anisotropic auxiliary layer includes at least one of a magnesium oxide (MgO) layer or a cobalt (Co) layer;
When the anisotropic auxiliary layer is a magnesium oxide layer, the magnetic layer includes at least one of a cobalt layer, an iron layer (Fe), a nickel (Ni) layer, a cobalt boride (CoB) layer, an iron boride (FeB) layer, a nickel boride (NiB) layer, a cobalt iron (CoFe) layer, an iron nickel (NiFe) layer, a cobalt nickel (CoNi) layer, a cobalt iron boron (CoFeB) layer, a cobalt iron platinum (CoFePt) layer, a cobalt iron palladium (CoFePd) layer, a cobalt iron terbium (CoFeTb) layer, a cobalt iron chromium (CoFeCr) layer, and a cobalt iron gadolinium (CoFeGd) layer;
When the anisotropic auxiliary layer is a cobalt layer, the magnetic layer includes at least one of a platinum (Pt) layer, a palladium (Pd) layer, and a nickel (Ni) layer.
The above combinations of the anisotropic auxiliary layers and the corresponding magnetic layers are combinations of composite layers with better perpendicular magnetic anisotropy obtained through a large number of theoretical calculations and experimental tests, and of course, other combinations of composite layers may be selected according to practical situations, or any one of the above magnetic layers may be selected to be directly used as the magnetic compensation layer 30 (i.e., the magnetic compensation layer 30 of the single-layer film), which is not limited herein. Referring to fig. 2, fig. 2 is a specific embodiment of the structure corresponding to fig. 1, in which the free layer 11 includes two cobalt-iron-boron layers and a tungsten (W) layer disposed between the two cobalt-iron-boron layers, the barrier layer 12 is a magnesium oxide layer, the reference layer 13A is a cobalt-iron-boron layer, a tungsten layer and a cobalt/platinum composite layer in sequence, the coupling layer 13B is a ruthenium layer, the pinning layer 13C is a cobalt layer and a cobalt/platinum composite layer, the isolation layer 20 is a ruthenium/tantalum composite layer, and the magnetic compensation layer 30 sequentially includes a cobalt layer, a ruthenium layer and a cobalt-nickel composite layer. The "number +A" in each layer in FIG. 2 indicates the thickness of that layer, A being the thickness in angstroms.
As a specific embodiment, the first given range is 0.8 to 1.2, inclusive, e.g., any one of 0.80, 1.05, or 1.20. The above-mentioned range is the optimal parameter range obtained by a large number of theoretical calculation and practical inspection, in the above-mentioned range, after the leakage magnetic fields generated by the magnetic compensation layer 30 and the SAF fixed layer 13 at the corresponding positions of the free layer cancel each other out, the residual magnetic field strength will not obviously affect the magnetic field inversion of the free layer 11, so as to ensure the consistent data holding capability of the MTJ component in different resistance states, and of course, the magnetic compensation layer and the SAF fixed layer can also be adjusted according to practical situations.
The magnetic compensation MTJ device provided by the invention comprises an MTJ unit, an isolation layer 20 and a magnetic compensation layer 30 which are sequentially stacked; the MTJ cell includes a free layer 11, a barrier layer 12, and a SAF fixed layer 13 stacked; at the same temperature within the preset temperature range, the ratio of the net magnetization of the SAF fixed layer corresponding to the SAF fixed layer 13 to the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer 30 does not exceed a first given range, and the direction of the net magnetization of the magnetic compensation layer is opposite to that of the net magnetization of the SAF fixed layer; the magnetic switching field of the magnetic compensation layer 30 is greater than the magnetic switching field of the free layer 11. According to the invention, the magnetic compensation layer 30 is additionally arranged on one side of the MTJ unit, the net residual magnetization intensity of the magnetic compensation layer 30 is similar to that of the SAF fixed layer 13 at the same temperature, but the magnetization directions are opposite, so that the leakage magnetic field generated by the magnetic compensation layer 30 and the leakage magnetic field generated by the fixed layer are mutually offset at the same temperature within a certain range at the corresponding position of the free layer, the balance of the data holding capacities of the MTJ device in different resistance states at different temperatures is further ensured, and the reliability and the yield of the MTJ device are improved.
Based on the first embodiment, the stability of the magnetic compensation layer 30 is further improved, so as to obtain a second embodiment, and a schematic structure diagram of the second embodiment is shown in fig. 5, where the second embodiment includes MTJ units, the isolation layer 20, and the magnetic compensation layer 30 that are sequentially stacked;
the MTJ cell includes a free layer 11, a barrier layer 12, and a SAF fixed layer 13 stacked;
At the same temperature within the preset temperature range, the ratio of the net magnetization of the SAF fixed layer corresponding to the SAF fixed layer 13 to the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer 30 does not exceed a first given range, and the direction of the net magnetization of the magnetic compensation layer is opposite to that of the net magnetization of the SAF fixed layer;
the magnetic switching field of the magnetic compensation layer 30 is greater than the magnetic switching field of the free layer 11;
an antiferromagnetic pinning layer 40 is also included;
The antiferromagnetic pinning layer 40 is disposed on a surface of the magnetic compensation layer 30 remote from the spacer layer 20.
The present embodiment is different from the above embodiment in that the antiferromagnetic pinning layer 40 is added to the magnetic compensation layer 30 in the present embodiment, and the other structures are the same as those of the above embodiment.
In this embodiment, the antiferromagnetic pinning layer 40 is disposed on the other surface of the magnetic compensation layer 30, and the antiferromagnetic pinning layer 40 can further increase the stability of the magnetization direction of the magnetic compensation layer 30 adjacent thereto, so as to improve the working stability of the MTJ device.
Of course, the magnetic compensation layer 30 in the present embodiment may be a composite layer or a single layer film, and the present invention is not limited thereto.
The invention also provides a manufacturing method of the magnetic compensation MTJ device, a flow diagram of one specific embodiment of which is shown in FIG. 6, which is called as a third specific embodiment, comprising:
s101: acquiring data of an MTJ unit to be processed; the MTJ unit to be processed corresponding to the data of the MTJ unit to be processed comprises a free layer, a barrier layer and an SAF fixed layer which are arranged in a stacked mode.
The MTJ cell data to be processed is basic data of the MTJ cell to be processed, such as size, thickness, structure, composition, and the like.
S102: determining reference temperature change magnetization data according to the MTJ unit data to be processed; the reference temperature-dependent magnetization data refer to data of the corresponding relationship between the net magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the temperature within a preset temperature range.
In this step, a certain MTJ cell to be processed may be produced according to the MTJ cell data to be processed, and then an experiment may be performed to measure the reference temperature-dependent magnetization data by placing the MTJ cell to be processed obtained by the production at different temperatures. Of course, it can be obtained by other means, such as computer simulation or deep learning, etc., and the present invention is not limited herein.
S103: determining magnetic compensation layer data according to the reference temperature change magnetization data, so that the ratio of the net magnetization intensity of the magnetic compensation layer corresponding to the magnetic compensation layer at the same temperature within a preset temperature range to the net magnetization intensity of the SAF fixed layer is not more than a first given range, the net magnetization intensity of the magnetic compensation layer is opposite to the net magnetization intensity of the SAF fixed layer, and the magnetic inversion field of the magnetic compensation layer is larger than the magnetic inversion field of the free layer.
After the reference temperature-dependent magnetization data are determined, only by adjusting the factors such as the structure, the size, the components and the like of the magnetic compensation layer 30, the net magnetization of the obtained magnetic compensation layer 30 is corresponding to the size of the reference temperature-dependent magnetization data at different temperatures, and the directions are opposite, and of course, the ratio of the net magnetization of the magnetic compensation layer to the net magnetization of the SAF fixed layer is as close as 1.
S104: setting the MTJ unit to be processed according to the data of the MTJ unit to be processed, setting the magnetic compensation layer according to the data of the magnetic compensation layer, and setting an isolation layer between the MTJ unit to be processed and the magnetic compensation layer to obtain a finished MTJ device.
The method for manufacturing the magnetic compensation MTJ device in this embodiment corresponds to the magnetic compensation MTJ device in the foregoing, and will not be described in detail here.
The invention provides a manufacturing method of a magnetic compensation MTJ device, which comprises the steps of obtaining data of an MTJ unit to be processed; the MTJ unit to be processed corresponding to the data of the MTJ unit to be processed comprises a free layer, a barrier layer and an SAF fixed layer which are arranged in a stacked manner; determining reference temperature change magnetization data according to the MTJ unit data to be processed; the reference temperature-dependent magnetization data refer to data of the corresponding relationship between the net magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the temperature within a preset temperature range; determining magnetic compensation layer data according to the reference temperature change magnetization data, so that the ratio of the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer to the net magnetization of the SAF fixed layer at the same temperature within a preset temperature range does not exceed a first given range, the net magnetization of the magnetic compensation layer and the net magnetization of the SAF fixed layer are opposite in direction, and the magnetic inversion field of the magnetic compensation layer is larger than the magnetic inversion field of the free layer; setting the MTJ unit to be processed according to the data of the MTJ unit to be processed, setting the magnetic compensation layer according to the data of the magnetic compensation layer, and setting an isolation layer between the MTJ unit to be processed and the magnetic compensation layer to obtain a finished MTJ device. According to the invention, the magnetic compensation layer is additionally arranged on one side of the MTJ unit, so that the leakage magnetic field generated by the magnetic compensation layer and the leakage magnetic field generated by the SAF fixed layer at the corresponding position of the free layer are mutually offset at the same temperature within a certain range, the balance of the data holding capacities of the MTJ device in different resistance states at different temperatures is further ensured, and the reliability and yield of the MTJ device are improved.
The present invention also provides an MRAM device comprising a magnetically compensated MTJ device as described in any of the above. The magnetic compensation MTJ device provided by the invention comprises an MTJ unit, an isolation layer 20 and a magnetic compensation layer 30 which are sequentially stacked; the MTJ cell includes a free layer 11, a barrier layer 12, and a SAF fixed layer 13 stacked; at the same temperature within the preset temperature range, the ratio of the net magnetization of the SAF fixed layer corresponding to the SAF fixed layer 13 to the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer 30 does not exceed a first given range, and the direction of the net magnetization of the magnetic compensation layer is opposite to that of the net magnetization of the SAF fixed layer; the magnetic switching field of the magnetic compensation layer 30 is greater than the magnetic switching field of the free layer 11. The magnetic compensation layer 30 is additionally arranged on one side of the MTJ unit, the net residual magnetization intensity of the magnetic compensation layer is similar to that of the SAF fixed layer at the same temperature, but the magnetization directions are opposite, so that the leakage magnetic field generated by the magnetic compensation layer and the leakage magnetic field generated by the fixed layer are mutually offset at the same temperature within a certain range at the corresponding position of the free layer, the balance of the data holding capability of the MTJ device in different resistance states at different temperatures is further ensured, and the reliability and the yield of the MTJ device are improved.
In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, so that the same or similar parts between the embodiments are referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.
It should be noted that in this specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The magnetic compensation MTJ device and the manufacturing method thereof, and the MRAM device provided by the present invention are described in detail above. The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present invention and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims.
Claims (10)
1. The magnetic compensation MTJ device is characterized by comprising an MTJ unit, an isolation layer and a magnetic compensation layer which are sequentially stacked;
the MTJ unit comprises a free layer, a barrier layer and an SAF fixed layer which are stacked;
Under the same temperature in a preset temperature range, the net residual magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the ratio of the net magnetization intensity of the magnetic compensation layer corresponding to the magnetic compensation layer do not exceed a first given range, and the direction of the net magnetization intensity of the magnetic compensation layer is opposite to that of the net magnetization intensity of the SAF fixed layer;
the magnetic switching field of the magnetic compensation layer is greater than the magnetic switching field of the free layer.
2. The magnetically compensated MTJ device of claim 1, wherein the magnetic compensation layer comprises a first compensation sublayer, a reverse coupling layer, and a second compensation sublayer in a stacked arrangement.
3. The magnetically compensated MTJ device of claim 2, wherein the first compensation sublayer and/or the second compensation sublayer are composite layers.
4. The magnetically compensated MTJ device of claim 3, wherein the composite layer comprises an anisotropic auxiliary layer and a magnetic layer in a stacked arrangement.
5. The magnetically compensated MTJ device of claim 4, wherein the anisotropic auxiliary layer comprises at least one of a magnesium oxide layer or a cobalt layer;
When the anisotropic auxiliary layer is a magnesium oxide layer, the magnetic layer comprises at least one of a cobalt layer, an iron layer, a nickel layer, a cobalt boride layer, an iron boride layer, a nickel boride layer, a cobalt iron layer, an iron nickel layer, a cobalt iron boron layer, a cobalt iron platinum layer, a cobalt iron palladium layer, a cobalt iron terbium layer, a cobalt iron chromium layer and a cobalt iron gadolinium layer;
When the anisotropic auxiliary layer is a cobalt layer, the magnetic layer includes at least one of a platinum layer, a palladium layer, and a nickel layer.
6. The magnetically compensated MTJ device of claim 2, wherein the reverse coupling layer comprises at least one of an iridium layer, a ruthenium layer.
7. The magnetically compensated MTJ device of claim 1, wherein the first given range is 0.8 to 1.2, inclusive.
8. The magnetic compensation MTJ device of any one of claims 1-7, further comprising an antiferromagnetic pinning layer;
the antiferromagnetic pinning layer is disposed on a surface of the magnetic compensation layer remote from the isolation layer.
9. An MRAM device comprising the magnetically compensated MTJ device of any of claims 1-8.
10. A method of manufacturing a magnetic compensation MTJ device, comprising:
acquiring data of an MTJ unit to be processed; the MTJ unit to be processed corresponding to the data of the MTJ unit to be processed comprises a free layer, a barrier layer and an SAF fixed layer which are arranged in a stacked manner;
Determining reference temperature change magnetization data according to the MTJ unit data to be processed; the reference temperature-dependent magnetization data refer to data of the corresponding relationship between the net magnetization intensity of the SAF fixed layer corresponding to the SAF fixed layer and the temperature within a preset temperature range;
Determining magnetic compensation layer data according to the reference temperature change magnetization data, so that the ratio of the net magnetization of the magnetic compensation layer corresponding to the magnetic compensation layer to the net magnetization of the SAF fixed layer at the same temperature within a preset temperature range does not exceed a first given range, the net magnetization of the magnetic compensation layer and the net magnetization of the SAF fixed layer are opposite in direction, and the magnetic inversion field of the magnetic compensation layer is larger than the magnetic inversion field of the free layer;
Setting the MTJ unit to be processed according to the data of the MTJ unit to be processed, setting the magnetic compensation layer according to the data of the magnetic compensation layer, and setting an isolation layer between the MTJ unit to be processed and the magnetic compensation layer to obtain a finished MTJ device.
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| CN202310326811.XA CN118742190A (en) | 2023-03-30 | 2023-03-30 | Magnetic compensation MTJ device, manufacturing method thereof and MRAM device |
| PCT/CN2023/137150 WO2024198492A1 (en) | 2023-03-30 | 2023-12-07 | Magnetic compensation mtj device, manufacturing method therefor, and mram device |
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| CN202310326811.XA CN118742190A (en) | 2023-03-30 | 2023-03-30 | Magnetic compensation MTJ device, manufacturing method thereof and MRAM device |
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| DE10142594A1 (en) * | 2001-08-31 | 2003-03-27 | Infineon Technologies Ag | Bias magnetic field compensation arrangement for magnetoresistive memory cell uses compensation layers magnetised for compensating bias magnetic field in memory layer |
| US7826256B2 (en) * | 2008-09-29 | 2010-11-02 | Seagate Technology Llc | STRAM with compensation element |
| US8053255B2 (en) * | 2009-03-03 | 2011-11-08 | Seagate Technology Llc | STRAM with compensation element and method of making the same |
| US9396781B2 (en) * | 2010-12-10 | 2016-07-19 | Avalanche Technology, Inc. | Magnetic random access memory having perpendicular composite reference layer |
| US9647202B2 (en) * | 2011-02-16 | 2017-05-09 | Avalanche Technology, Inc. | Magnetic random access memory with perpendicular enhancement layer |
| CN105428522B (en) * | 2015-12-01 | 2018-07-20 | 中电海康集团有限公司 | A kind of magnetic tunnel junction for STT-MRAM |
| CN105552214B (en) * | 2015-12-09 | 2018-11-09 | 中电海康集团有限公司 | A kind of magneto-resistor random access memory of perpendicular magnetization |
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