CN112397636A - Magnetic tunnel junction and method for reducing process fluctuation of free layer of magnetic tunnel junction - Google Patents
Magnetic tunnel junction and method for reducing process fluctuation of free layer of magnetic tunnel junction Download PDFInfo
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- 230000005291 magnetic effect Effects 0.000 title claims abstract description 104
- 238000000034 method Methods 0.000 title claims description 38
- 230000004888 barrier function Effects 0.000 claims abstract description 34
- 239000000463 material Substances 0.000 claims description 47
- 229910019236 CoFeB Inorganic materials 0.000 claims description 21
- 230000008878 coupling Effects 0.000 claims description 21
- 238000010168 coupling process Methods 0.000 claims description 21
- 238000005859 coupling reaction Methods 0.000 claims description 21
- 229910003321 CoFe Inorganic materials 0.000 claims description 19
- -1 FeB Inorganic materials 0.000 claims description 19
- 229910052742 iron Inorganic materials 0.000 claims description 19
- 239000000956 alloy Substances 0.000 claims description 17
- 229910001291 heusler alloy Inorganic materials 0.000 claims description 17
- 230000005290 antiferromagnetic effect Effects 0.000 claims description 10
- 239000000696 magnetic material Substances 0.000 claims description 6
- 230000005389 magnetism Effects 0.000 claims description 4
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- 239000000758 substrate Substances 0.000 abstract description 9
- 230000000694 effects Effects 0.000 abstract description 7
- 239000002994 raw material Substances 0.000 description 13
- GSWGDDYIUCWADU-UHFFFAOYSA-N aluminum magnesium oxygen(2-) Chemical compound [O--].[Mg++].[Al+3] GSWGDDYIUCWADU-UHFFFAOYSA-N 0.000 description 4
- 229910052797 bismuth Inorganic materials 0.000 description 4
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 4
- FBGGJHZVZAAUKJ-UHFFFAOYSA-N bismuth selenide Chemical compound [Se-2].[Se-2].[Se-2].[Bi+3].[Bi+3] FBGGJHZVZAAUKJ-UHFFFAOYSA-N 0.000 description 4
- 238000005229 chemical vapour deposition Methods 0.000 description 4
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- 239000011651 chromium Substances 0.000 description 4
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- 239000000395 magnesium oxide Substances 0.000 description 4
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- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 2
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- 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
- 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
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- H10N50/00—Galvanomagnetic devices
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- H—ELECTRICITY
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- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N50/00—Galvanomagnetic devices
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- H—ELECTRICITY
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- H10N59/00—Integrated devices, or assemblies of multiple devices, comprising at least one galvanomagnetic or Hall-effect element covered by groups H10N50/00 - H10N52/00
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Abstract
The invention provides a magnetic tunnel junction, which at least comprises a reference layer, a barrier layer, a magnetic buffer layer and a free layer which are sequentially stacked; wherein the magnetic buffer layer is more ductile than the free layer. The invention adds a thin magnetic buffer layer on the surface of the barrier layer, and provides a smoother substrate by utilizing the better ductility of the buffer layer, so that the uniformity of a subsequently deposited free layer film is better, and the TMR effect of a magnetic tunnel cannot be damaged.
Description
Technical Field
The invention relates to the technical field of magnetic random access memories, in particular to a magnetic tunnel junction and a method for reducing process fluctuation of a free layer of the magnetic tunnel junction.
Background
The magnetic random access memory has the advantages of long service life, low power consumption, nonvolatility and the like, and mainly switches between different resistances by turning the magnetization direction of the free layer to be parallel or antiparallel to the magnetization direction of the reference layer so as to erase and write data '0' or '1'.
Due to process fluctuations, the performance of all bits in a memory array may not be completely uniform, but rather may be distributed over a range that must be planned in advance during device design. Such process fluctuations also exist for magnetic random access memories, and the requirements and considerations for such process fluctuations vary for different parts of the magnetic tunnel junction.
The reference layer is stable enough during operation of the device and therefore has a coercivity large enough that the minimum value of coercivity is above a critical threshold.
The switching of the magnetic random access memory between '0' and '1' is realized by the overturning of the free layer, so that the smaller the coercive force of the free layer is, the easier the overturning is, the smaller the required driving force is, and the lower the power consumption is; however, if the coercivity is too low, there is a risk that the free layer will be flipped by the read current/thermal perturbation, and thus the free layer must meet a certain thermal stability factor. The design of the device of the free layer has to meet certain requirements at the upper limit and the lower limit, and due to the existence of process fluctuation, when the device crosses the lower limit, part of bits have the problem of error erasing; when the cross is generated with the upper limit, the power consumption of the whole array can be improved, and the service life is reduced.
Disclosure of Invention
The magnetic tunnel junction and the method for reducing the process fluctuation of the free layer of the magnetic tunnel junction can improve the uniformity of the free layer and reduce the process fluctuation of the free layer.
In a first aspect, the present invention provides a magnetic tunnel junction, which at least includes a reference layer, a barrier layer, a magnetic buffer layer, and a free layer, which are sequentially stacked; wherein the magnetic buffer layer is more ductile than the free layer.
Optionally, the magnetic buffer layer is made of a material having a magnetic property stronger than that of the free layer.
Optionally, a thickness of the magnetic buffer layer is less than a thickness of the free layer.
Optionally, the ratio of the thickness of the buffer layer to the thickness of the free layer is 0.5/9-1.5/8.5.
Optionally, the magnetic buffer layer comprises one or a combination of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials.
Optionally, the device further comprises an antiferromagnetically coupling layer and a pinning layer which are arranged in a laminated manner; the side surface of the antiferromagnetic coupling layer facing away from the pinned layer is in contact with the reference layer.
Optionally, the free layer comprises a first free layer, a coupling layer and a second free layer which are sequentially stacked, and one side of the first free layer, which faces away from the coupling layer, is in contact with the barrier layer; the materials of the first free layer and the second free layer are both magnetic materials.
The invention is designed aiming at the following conditions: the free layer is arranged at the magnetic tunnel junction of the uppermost layer, and due to the deposition of the multilayer film below the free layer, the surface flatness of the barrier layer is reduced after the barrier layer is deposited, so that the process fluctuation of the magnetism of the free layer is more easily increased. Therefore, the invention adds a thin magnetic buffer layer on the surface of the barrier layer, and provides a smoother substrate by utilizing the better ductility of the buffer layer, so that the uniformity of the free layer film deposited subsequently is better, and the TMR effect of the magnetic tunnel is not damaged.
In a second aspect, the present invention provides a method for reducing process fluctuation of a free layer of a magnetic tunnel junction, including:
providing a reference layer and a barrier layer which are sequentially stacked from bottom to top;
a magnetic buffer layer and a free layer are sequentially stacked on the barrier layer, and the magnetic buffer layer has a higher ductility than the free layer.
Optionally, the thickness of the buffer layer is controlled to be smaller than the thickness of the free layer.
Optionally, the ratio of the thickness of the magnetic buffer layer to the thickness of the free layer is controlled to be 0.5/9-1.5/8.5.
Optionally, a material having a magnetic property stronger than that of the material of the free layer is selected as the buffer layer material.
Optionally, one or a combination of more of Co, Fe, CoFe, FeB, CoFeB and Heusler alloy materials is selected as the material of the buffer layer.
Optionally, forming the free layer comprises:
and sequentially forming a first free layer, a coupling layer and a second free layer on the magnetic buffer layer.
Optionally, the method further comprises: sequentially laminating a pinning layer and an antiferromagnetic coupling layer;
the reference layer is formed on the antiferromagnetically-coupled layer.
The invention adds a thin magnetic buffer layer on the surface of the barrier layer, and provides a smoother substrate by utilizing the better ductility of the buffer layer, so that the uniformity of a subsequently deposited free layer film is better, and the TMR effect of a magnetic tunnel cannot be damaged.
Drawings
FIG. 1 is a schematic structural diagram of an embodiment of the present invention;
fig. 2 is a schematic structural diagram of another embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
An embodiment of the present invention provides a magnetic tunnel junction, as shown in fig. 1, including a reference layer 1, a barrier layer 2, a magnetic buffer layer 3, and a free layer 4, which are sequentially stacked; among them, the magnetic buffer layer 3 has higher ductility than the free layer 4.
The material of the reference layer 1 is a ferromagnetic material, and one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials can be selected, and the magnetization direction of the reference layer 1 is fixed.
The barrier layer 2 is made of a non-magnetic material, and may be one or a combination of several selected from magnesium oxide, aluminum oxide, magnesium aluminum oxide, hafnium oxide, tantalum oxide, bismuth telluride, and bismuth selenide.
The material of the magnetic buffer layer 3 is also a magnetic material, and one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials can be selected.
The material of the free layer 4 is ferromagnetic material, and can be selected from one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy material.
The magnetic buffer layer 3 needs to be more ductile than the free layer 4, and for this purpose, a material having better ductility than the material of the free layer 4 may be selected depending on the material of the free layer 4 that has been selected. The magnetic buffer layer 3 may be formed to have a crystal structure that is more ductile than the free layer 4.
As an alternative to this embodiment, the following table:
| Co/CoFeB | standard deviation of damping coefficient | Damping coefficient test point discreteness | Discrete standard deviation |
| 0/10 | 0.00074 | 186.4 | 13.8 |
| 1.0/9.0 | 0.00046 | 155.9 | 10.3 |
| 1.5/8.5 | 0.00041 | 139.2 | 8 |
In the above embodiment, Co is selected as the material of the magnetic buffer layer 3, CoFeB is selected as the material of the free layer 4, and it can be seen in the graph that when the ratio of the thickness of the buffer layer to the thickness of the free layer 4 is 1/9 and 1.5/8.5, it can be seen that three performance parameters of damming error bar, dH0, dH0error bar are greatly reduced, and thus it can be seen that the uniformity of the free layer 4 is significantly improved with the addition of the buffer layer.
This embodiment provides a smoother substrate by adding a thin magnetic buffer layer 3 on the surface of the barrier layer 2, and by utilizing its better ductility, the film of the free layer 4 deposited subsequently has better uniformity and does not impair the TMR effect of the magnetic tunnel.
Example 2
The present embodiment provides a magnetic tunnel junction, as shown in fig. 2, including a pinned layer 6, an antiferromagnetic coupling layer 5, a reference layer 1, a barrier layer 2, a magnetic buffer layer 3, and a free layer 4, which are sequentially stacked; among them, the magnetic buffer layer 3 has higher ductility than the free layer 4. The free layer 4 includes a first free layer 41, a coupling layer 42, and a second free layer 43, which are sequentially stacked. Wherein the first free layer 41 is in contact with the buffer layer. A capping layer 7 is further laminated on the second free layer 43 in order to protect the second free layer 43.
The material of the pinning layer 6 can be selected from one or more of Co, Fe, CoFe, NiFe, NiFeCo, CoFeB, CoMnB or CoNbZr.
The antiferromagnetic coupling layer 5 may be one or a combination of ruthenium, chromium, rhodium and iridium.
The material of the reference layer 1 is a ferromagnetic material, and one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials can be selected, and the magnetization direction of the reference layer 1 is fixed.
The barrier layer 2 is made of a non-magnetic material, and may be one or a combination of several selected from magnesium oxide, aluminum oxide, magnesium aluminum oxide, hafnium oxide, tantalum oxide, bismuth telluride, and bismuth selenide.
The material of the magnetic buffer layer 3 is also a magnetic material, and one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials can be selected.
The materials of the first free layer 41 and the second free layer 43 are all ferromagnetic materials, and one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials can be selected. The coupling layer 42 may be one or a combination of Ta, W, Nb, Ru, Ti, Cr, V, Mo, and Re.
The magnetic buffer layer 3 needs to be more ductile than the free layer 4, and for this purpose, a material having better ductility than the material of the free layer 4 may be selected depending on the material of the free layer 4 that has been selected. The magnetic buffer layer 3 may be formed to have a crystal structure that is more ductile than the free layer 4.
This embodiment provides a smoother substrate by adding a thin magnetic buffer layer 3 on the surface of the barrier layer 2, and by utilizing its better ductility, the film of the free layer 4 deposited subsequently has better uniformity and does not impair the TMR effect of the magnetic tunnel.
As an alternative embodiment of this embodiment, the magnetic buffer layer 3 is made of a material having a magnetic property stronger than that of the material of the free layer 4.
As an alternative to this embodiment, the thickness of the magnetic buffer layer 3 is smaller than the thickness of the free layer 4.
As a further optional implementation manner of the embodiment, the ratio of the thickness of the buffer layer to the thickness of the free layer 4 is 0.5/9 to 1.5/8.5.
Example 3
The embodiment provides a method for reducing process fluctuation of a free layer of a magnetic tunnel junction, which comprises the following steps:
providing a reference layer and a barrier layer which are sequentially stacked from bottom to top;
a magnetic buffer layer and a free layer are sequentially stacked on the barrier layer, and the magnetic buffer layer has a higher ductility than the free layer.
The specific forming process is as follows: one or more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials are selected as raw materials, and the reference layer is formed on the substrate by the raw materials.
Selecting one or a composition of more of magnesium oxide, aluminum oxide, magnesium aluminum oxide, hafnium oxide, tantalum oxide, bismuth telluride or bismuth selenide as a raw material, and forming a barrier layer on the reference layer.
One or more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials are selected as raw materials, and a magnetic buffer layer is formed on the barrier layer.
One or more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials are selected as raw materials to form a free layer on the magnetic buffer layer.
The above layers may be formed by Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), radio frequency sputtering (RF), ion spraying (PSC), or the like.
As an alternative to this embodiment, in selecting the material of the magnetic buffer layer, a material is selected that is more ductile than the free layer material.
As another alternative to this embodiment, the same material as the free layer material may be selected when selecting the magnetic buffer layer material, and a crystal structure having better ductility than the free layer may be formed when forming the magnetic buffer layer.
As an alternative to this embodiment, a material with a magnetic property stronger than that of the material of the free layer is selected as the buffer layer material.
As an optional implementation manner of this embodiment, the thickness of the buffer layer is controlled to be smaller than the thickness of the free layer.
As a further optional implementation manner of the embodiment, the ratio of the thickness of the magnetic buffer layer to the thickness of the free layer is controlled to be 0.5/9 to 1.5/8.5.
For the MTJ structure with the free layer on the uppermost layer, due to the deposition of the multilayer film below the free layer, the surface flatness of the barrier layer is reduced after the barrier layer is deposited, and the magnetic process fluctuation is more easily increased. Therefore, the present embodiment adds a thin magnetic buffer layer on the surface of the barrier layer, utilizes its better ductility to provide a smoother substrate, and utilizes its stronger magnetism to homogenize the magnetic moment of the free layer, so that the uniformity of the subsequently deposited free layer film is better, and the TMR effect of the MTJ is not damaged.
Example 4
The embodiment provides a method for reducing process fluctuation of a free layer of a magnetic tunnel junction, which comprises the following steps:
providing a pinning layer, an antiferromagnetic coupling layer, a reference layer and a barrier layer which are sequentially laminated from bottom to top;
a magnetic buffer layer and a free layer are sequentially stacked on the barrier layer, and the magnetic buffer layer has a higher ductility than the free layer.
The specific forming process is as follows: one or a combination of more of Co, Fe, CoFe, NiFe, NiFeCo, CoFeB, CoMnB or CoNbZr is selected as a raw material to form a pinning layer on the substrate.
One or more of ruthenium, chromium, rhodium or iridium is selected as raw material to form an antiferromagnetic coupling layer on the pinning layer.
One or more of Co, Fe, CoFe, FeB, CoFeB and Heusler alloy materials are selected as raw materials, so that the reference layer is formed on the antiferromagnetic coupling layer.
Selecting one or a composition of more of magnesium oxide, aluminum oxide, magnesium aluminum oxide, hafnium oxide, tantalum oxide, bismuth telluride or bismuth selenide as a raw material, and forming a barrier layer on the reference layer.
One or more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials are selected as raw materials, and a magnetic buffer layer is formed on the barrier layer.
The specific step of forming the free layer includes forming a first free layer on the magnetic buffer layer by selecting one or a combination of several of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials as a raw material. One or more of Ta, W, Nb, Ru, Ti, Cr, V, Mo and Re is selected as a raw material to form a coupling layer on the first free layer. And selecting one or a combination of more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials as a raw material to form a second free layer on the coupling layer.
The above layers may be formed by Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), radio frequency sputtering (RF), ion spraying (PSC), or the like.
As an alternative to this embodiment, in selecting the material of the magnetic buffer layer, a material is selected that is more ductile than the free layer material.
As another alternative to this embodiment, the same material as the free layer material may be selected when selecting the magnetic buffer layer material, and a crystal structure having better ductility than the free layer may be formed when forming the magnetic buffer layer.
As an alternative to this embodiment, a material with a magnetic property stronger than that of the material of the free layer is selected as the buffer layer material.
As an optional implementation manner of this embodiment, the thickness of the buffer layer is controlled to be smaller than the thickness of the free layer.
As a further optional implementation manner of the embodiment, the ratio of the thickness of the magnetic buffer layer to the thickness of the free layer is controlled to be 0.5/9 to 1.5/8.5.
As an alternative to this embodiment, a capping layer may also be formed on the free layer.
For the MTJ structure with the free layer on the uppermost layer, due to the deposition of the multilayer film below the free layer, the surface flatness of the barrier layer is reduced after the barrier layer is deposited, and the magnetic process fluctuation is more easily increased. Therefore, the present embodiment adds a thin magnetic buffer layer on the surface of the barrier layer, utilizes its better ductility to provide a smoother substrate, and utilizes its stronger magnetism to homogenize the magnetic moment of the free layer, so that the uniformity of the subsequently deposited free layer film is better, and the TMR effect of the MTJ is not damaged.
The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (14)
1. A magnetic tunnel junction, characterized by: the device at least comprises a reference layer, a barrier layer, a magnetic buffer layer and a free layer which are sequentially stacked; wherein the magnetic buffer layer is more ductile than the free layer.
2. The magnetic tunnel junction of claim 1 wherein: the magnetic buffer layer is made of a material having a magnetic property stronger than that of the free layer.
3. The magnetic tunnel junction of claim 1 wherein: the thickness of the magnetic buffer layer is smaller than that of the free layer.
4. The magnetic tunnel junction of claim 3 wherein: the thickness ratio of the buffer layer to the free layer is 0.5/9-1.5/8.5.
5. The magnetic tunnel junction of claim 1 wherein: the magnetic buffer layer comprises one or a combination of more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials.
6. The magnetic tunnel junction of claim 1 wherein: the anti-ferromagnetic coupling layer and the pinning layer are arranged in a laminated mode; the side surface of the antiferromagnetic coupling layer facing away from the pinned layer is in contact with the reference layer.
7. The magnetic tunnel junction of claim 1 wherein: the free layer comprises a first free layer, a coupling layer and a second free layer which are sequentially stacked, wherein one side of the first free layer, which is far away from the coupling layer, is in contact with the barrier layer; the materials of the first free layer and the second free layer are both magnetic materials.
8. A method for reducing the process fluctuation of a free layer of a magnetic tunnel junction is characterized in that: the method comprises the following steps:
providing a reference layer and a barrier layer which are sequentially stacked from bottom to top;
a magnetic buffer layer and a free layer are sequentially stacked on the barrier layer, and the magnetic buffer layer has a higher ductility than the free layer.
9. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 8, wherein: and controlling the thickness of the buffer layer to be smaller than that of the free layer.
10. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 9, wherein: controlling the thickness ratio of the magnetic buffer layer to the free layer to be 0.5/9-1.5/8.5.
11. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 8, wherein: and selecting a material with magnetism stronger than that of the material of the free layer as a buffer layer material.
12. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 8, wherein: selecting one or a combination of more of Co, Fe, CoFe, FeB, CoFeB or Heusler alloy materials as the material of the buffer layer.
13. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 8, wherein: forming the free layer includes:
and sequentially forming a first free layer, a coupling layer and a second free layer on the magnetic buffer layer.
14. The method of reducing process variation of a free layer of a magnetic tunnel junction according to claim 8, wherein: further comprising: sequentially laminating a pinning layer and an antiferromagnetic coupling layer;
the reference layer is formed on the antiferromagnetically-coupled layer.
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| CN201910741890.4A CN112397636B (en) | 2019-08-12 | 2019-08-12 | Magnetic tunnel junction and method for reducing process fluctuation of free layer of magnetic tunnel junction |
| PCT/CN2020/098497 WO2021027404A1 (en) | 2019-08-12 | 2020-06-28 | Magnetic tunnel junction and method for reducing magnetic tunnel junction free layer process fluctuations |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003298145A (en) * | 2002-03-29 | 2003-10-17 | Toshiba Corp | Magnetoresistive effect element and magnetic memory device |
| US20040246634A1 (en) * | 2001-08-15 | 2004-12-09 | Kabushiki Kaisha Toshiba | Magnetoresistance effect element, magnetic head and magnetic reproducing apparatus |
| US20110169111A1 (en) * | 2010-01-08 | 2011-07-14 | International Business Machines Corporation | Optimized free layer for spin torque magnetic random access memory |
| CN105633276A (en) * | 2014-10-29 | 2016-06-01 | 华为技术有限公司 | Memory cell based on magnetic alloy composite film, preparation method thereof and magnetic storage device comprising memory cell |
| CN105702853A (en) * | 2016-03-04 | 2016-06-22 | 北京航空航天大学 | Spin-transfer torque magnetic memory unit |
| US20170170390A1 (en) * | 2015-12-11 | 2017-06-15 | Imec Vzw | Magnetic memory device having buffer layer |
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| CN100552810C (en) * | 2006-02-16 | 2009-10-21 | 财团法人工业技术研究院 | Magnetic cell and its manufacture method |
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040246634A1 (en) * | 2001-08-15 | 2004-12-09 | Kabushiki Kaisha Toshiba | Magnetoresistance effect element, magnetic head and magnetic reproducing apparatus |
| JP2003298145A (en) * | 2002-03-29 | 2003-10-17 | Toshiba Corp | Magnetoresistive effect element and magnetic memory device |
| US20110169111A1 (en) * | 2010-01-08 | 2011-07-14 | International Business Machines Corporation | Optimized free layer for spin torque magnetic random access memory |
| CN105633276A (en) * | 2014-10-29 | 2016-06-01 | 华为技术有限公司 | Memory cell based on magnetic alloy composite film, preparation method thereof and magnetic storage device comprising memory cell |
| US20170170390A1 (en) * | 2015-12-11 | 2017-06-15 | Imec Vzw | Magnetic memory device having buffer layer |
| CN105702853A (en) * | 2016-03-04 | 2016-06-22 | 北京航空航天大学 | Spin-transfer torque magnetic memory unit |
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| CN112397636B (en) | 2022-08-26 |
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