CN115020099B - Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film - Google Patents
Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film Download PDFInfo
- Publication number
- CN115020099B CN115020099B CN202210582217.2A CN202210582217A CN115020099B CN 115020099 B CN115020099 B CN 115020099B CN 202210582217 A CN202210582217 A CN 202210582217A CN 115020099 B CN115020099 B CN 115020099B
- Authority
- CN
- China
- Prior art keywords
- layer
- ndfeb
- thick film
- permanent magnet
- hard magnetic
- 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.)
- Active
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 124
- 229910001172 neodymium magnet Inorganic materials 0.000 title claims abstract description 69
- 238000000034 method Methods 0.000 title claims abstract description 54
- 230000002708 enhancing effect Effects 0.000 title claims abstract description 10
- 238000002955 isolation Methods 0.000 claims abstract description 34
- 230000008569 process Effects 0.000 claims abstract description 10
- 229910052751 metal Inorganic materials 0.000 claims abstract description 9
- 239000002184 metal Substances 0.000 claims abstract description 9
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 9
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 5
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 30
- 238000004544 sputter deposition Methods 0.000 claims description 28
- 239000000758 substrate Substances 0.000 claims description 25
- 125000006850 spacer group Chemical group 0.000 claims description 17
- 238000000151 deposition Methods 0.000 claims description 11
- 238000000137 annealing Methods 0.000 claims description 10
- 238000002360 preparation method Methods 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 8
- 229910052761 rare earth metal Inorganic materials 0.000 claims description 5
- 150000002910 rare earth metals Chemical class 0.000 claims description 5
- 230000008021 deposition Effects 0.000 claims description 4
- 238000011065 in-situ storage Methods 0.000 claims description 3
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 2
- 238000001816 cooling Methods 0.000 claims description 2
- 239000010410 layer Substances 0.000 abstract description 191
- 239000002356 single layer Substances 0.000 abstract description 10
- 150000002739 metals Chemical class 0.000 abstract 1
- 239000010408 film Substances 0.000 description 76
- 230000004888 barrier function Effects 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 10
- 239000013077 target material Substances 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 5
- 239000013078 crystal Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000000696 magnetic material Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 229910052750 molybdenum Inorganic materials 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- HMUNWXXNJPVALC-UHFFFAOYSA-N 1-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperazin-1-yl]-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethanone Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)N1CCN(CC1)C(CN1CC2=C(CC1)NN=N2)=O HMUNWXXNJPVALC-UHFFFAOYSA-N 0.000 description 2
- 230000005294 ferromagnetic effect Effects 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000005477 sputtering target Methods 0.000 description 2
- LDXJRKWFNNFDSA-UHFFFAOYSA-N 2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-1-[4-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]piperazin-1-yl]ethanone Chemical compound C1CN(CC2=NNN=C21)CC(=O)N3CCN(CC3)C4=CN=C(N=C4)NCC5=CC(=CC=C5)OC(F)(F)F LDXJRKWFNNFDSA-UHFFFAOYSA-N 0.000 description 1
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 230000005347 demagnetization Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000011089 mechanical engineering Methods 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000007665 sagging Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/0273—Imparting anisotropy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
- H01F1/0571—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
- H01F1/0572—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes with a protective layer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Thin Magnetic Films (AREA)
Abstract
The invention provides a method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film. According to the method, the isolation layer is inserted in the growing process of the NdFeB-based permanent magnet thick film, so that the NdFeB-based single-layer thick film is changed into the NdFeB-based multi-layer thick film, and the perpendicular magnetic anisotropy of the NdFeB-based multi-layer thick film is remarkably enhanced. The isolating layer is made of high-melting-point nonferromagnetic metals Ta, mo, W and the like, and the magnetic property of the isolating layer is obviously changed by changing the thickness and the layer number of the isolating layer. The invention solves the problem that the vertical magnetic anisotropy of the NdFeB-based permanent magnet thick film is reduced along with the thickness increase, can obtain the NdFeB-based permanent magnet thick film with strong vertical magnetic anisotropy and high coercivity, and has practical application value in miniature permanent magnet motors, miniature electric mechanical systems and miniature sensors.
Description
Technical Field
The invention relates to the technical field of permanent magnet material preparation, and particularly provides a method for enhancing vertical magnetic anisotropy of an NdFeB-based permanent magnet thick film.
Background
Permanent magnetic materials are an important branch in magnetic materials, and are widely applied to the fields of automobile industry, wind power generation, energy-saving household appliances, electronic information industry and the like. The permanent magnet motor adopts the magnetic field generated by the permanent magnet, does not need exciting coils or exciting current, has high efficiency and simple structure, can reduce power consumption by 30% -35%, is a good energy-saving motor, and is more and more widely applied along with the rapid development of high-performance permanent magnet materials and control technologies.
The magnetic performance of the permanent magnet material mainly comprises residual magnetism, coercive force, maximum magnetic energy product, temperature stability and the like, and in addition, the size, the weight, the volume, the manufacturing cost and the like of the permanent magnet material are key factors for determining the quality performance of the permanent magnet motor. Generally, the higher the magnetic energy product, the larger the output energy of the motor; the higher the coercive force is, the stronger the working magnetic field and the demagnetizing resistance of the motor are, and the wider the working temperature range is; the higher the rectangle degree of the demagnetization curve is, the smaller the dynamic loss of the motor is; the higher the resistivity of the permanent magnet, the less eddy current loss. The miniature permanent magnet motor used in modern electronic information technology is required to be small, light, large in torque, high in precision and good in controllability, so that the permanent magnet material is required to be high in remanence, high in coercive force, strong in perpendicular magnetic anisotropy, small in size and small in installation size.
Furthermore, microelectromechanical systems (MEMS) as an industrial technology integrating microelectronics with mechanical engineering, operate in the micrometer scale, consisting of components with dimensions of 1 to 100 micrometers. Typical dimensions for typical microelectromechanical devices are between 20 microns and one millimeter. Devices with energy conversion and transfer functions in the size range from millimeters to micrometers can be fabricated using permanent magnet materials in combination with MEMS.
With Nd 2 Fe 14 The permanent magnet composed of the B base has excellent permanent magnet performance, and has great application value in miniature permanent magnet motors or micro-electromechanical systems if the permanent magnet is made into a film form. NdFeB magnets are too brittle, however, and the limit of the thickness of the processed bulk sample is several hundred microns. Therefore, the magnetron sputtering method is adopted to prepare the high-performance permanent magnet thick film with the thickness of tens of micrometers, which can be directly applied to the out-of-plane perpendicular anisotropy of a miniature permanent magnet motor or a miniature electromechanical system. However, thick film growth is distinguished from nano-scale thin film growth, with significant differences in growth conditions and magnetic properties. First, thick films require large sputter rates and long-term stable sputtering atmospheres and temperatures during deposition. Second, as the film thickness increases, the residual internal stress increases, which tends to cause delamination of the substrate and thick film and bending of the thick film. Similarly, as the thickness increases, the C-axis orientation gradually tends to disorder toward isotropy, which is disadvantageous in producing a strong perpendicular magnetic anisotropic thick film, and limits the application. At present, the direct preparation of the NdFeB-based thick film magnet by utilizing a magnetron sputtering method has the problems that the bonding force is reduced continuously and is easy to fall off along with the continuous increase of the thickness in the micrometer scale range, the perpendicular magnetic anisotropy is reduced continuously and finally tends to be magnetic isotropy, the coercive force is reduced continuously and the like.
Disclosure of Invention
Aiming at the problem that the perpendicular magnetic anisotropy and the binding force are continuously reduced along with the thickness increase, the invention aims to provide a method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film, and the method can directly prepare a strong perpendicular magnetic anisotropy NdFeB-based thick film with the thickness of tens of micrometers by using a magnetron sputtering method. The preparation of the out-of-plane perpendicular anisotropic micron-level high-performance rare earth permanent magnet thick film which can be directly applied to a miniature permanent magnet motor or a micro-electromechanical system by adopting a magnetron sputtering method is possible.
The technical scheme of the invention is as follows:
a method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film is characterized by comprising the following steps: the perpendicular magnetic anisotropy of the NdFeB-based permanent magnet thick film is greatly enhanced by inserting an isolating layer in the growing process of the NdFeB-based permanent magnet thick film.
As a preferable technical scheme:
the spacer layer is a high melting point non-ferromagnetic metal such as one or more of Ta, mo, W, ti, hf, preferably Ta as spacer layer, the NdFeB-based permanent magnet thick film perpendicular magnetic anisotropy is enhanced more.
According to the invention, one or more isolating layers are inserted in the growing process of the NdFeB-based permanent magnet thick film, the thickness of each isolating layer is 3-20nm, the NdFeB-based multi-layer thick film inserted with the isolating layers and the original NdFeB-based single-layer thick film are in the same thickness level, and the total thickness of the NdFeB-based permanent magnet thick film is 5-50 mu m.
In the invention, the adjacent hard magnetic layer and isolation layer in the NdFeB-based permanent magnet thick film form a hard magnetic layer/isolation layer repeating unit, wherein the repeating unit means that the (hard magnetic layer/isolation layer) structure can be repeated continuously, the number of repeated times is increased continuously along with the increase of the number of layers inserted into the isolation layer under the condition that the total thickness is changed or unchanged, and the number of layers of the multilayer film is increased.
The hard magnetic layer is an NdFeB-based rare earth permanent magnetic material, and the main components of the hard magnetic layer are Nd, fe and B, wherein part of Nd can be replaced by one or more of Dy, pr, ce, tb and other rare earth metals, and part of Fe can be replaced by one or more of Co, al, ga, nb and other elements.
The vertical magnetic anisotropy of the NdFeB-based permanent magnet thick film added with the isolating layer is improved by 3-5 times compared with that of the prior art, and the high coercivity of the thick film is maintained to be near 1.9T.
The invention also provides an NdFeB-based permanent magnet thick film with strong perpendicular magnetic anisotropy, which is characterized in that: the NdFeB-based permanent magnet thick film sequentially comprises the following components from inside to outside: the device comprises a substrate, a buffer layer, a hard magnetic layer/isolation layer repeating unit, a hard magnetic layer and a covering layer, wherein the hard magnetic layer is an NdFeB-based rare earth permanent magnet material, and the isolation layer is a high-melting-point nonferromagnetic metal.
Wherein: the substrate comprises a micro-electromechanical system compatible Si substrate and SiO 2 A substrate or a Si substrate pre-patterned; the buffer layer comprises Ta, mo, W, ti, al 2 O 3 Or a combination thereof; the cover layer includes Ta, mo, W, ti or is formed from a combination thereof.
As a preferred embodiment, the hard magnetic layer/spacer repeat unit has a thickness of 0.5-3 μm, wherein the spacer thickness is in the range of 9nm to 20nm, preferably 1 μm hard magnetic layer plus 9nm spacer.
The hard magnetic layer is most preferably 1 μm thick in the hard magnetic layer/spacer repeat unit, and the spacer is most preferably 9nm thick, in view of the growth efficiency and performance.
The invention relates to a preparation method of an NdFeB-based permanent magnet thick film with strong perpendicular magnetic anisotropy, which is characterized in that all film layers are grown by adopting a direct current magnetron sputtering technology, and the specific steps are as follows:
1) Buffer layer: directly depositing a buffer layer on a substrate by adopting a direct current magnetron sputtering method;
2) A hard layer/spacer repeat unit, a hard layer: after heating, adopting a direct current magnetron sputtering method to deposit the hard magnetic layer on the buffer layer, wherein the sputtering temperature is 450-650 ℃, and the thickness of each layer is 500nm-15 mu m; directly depositing an isolation layer on the hard magnetic layer by adopting a direct current magnetron sputtering method, wherein the sputtering temperature of the isolation layer is consistent with that of the hard magnetic layer, the isolation layer is deposited after cooling is not needed, and the thickness of each layer is 3-20nm (preferably 9-15 nm); repeatedly growing the hard magnetic layer and the isolation layer by repeating the above operation to obtain a plurality of hard magnetic layer/isolation layer repeating units, and depositing a hard magnetic layer on the last hard magnetic layer/isolation layer repeating unit;
3) And (3) covering layer: after the sputtering temperature is reduced, adopting a direct current magnetron sputtering method to directly deposit a cover layer on the last hard magnetic layer;
4) And (3) annealing: after the cover layer deposition is finished, the temperature is increased to be higher than the sputtering temperature for in-situ annealing, the annealing temperature is 600-800 ℃, and the annealing time is 15-30min.
As a preferable technical scheme:
in step 1), the sputtering temperature is preferably 25-300 ℃, and the thickness increases with the increase of the total thickness of the hard magnetic layer, not less than 100nm.
In the step 2), the sputtering target material used by the hard magnetic layer is a self-made alloy target material, and the nominal component of the target material is Nd 15 DyFe 65 Co 10 B 10 . The target material is prepared by adopting a powder metallurgy method, and the specific process comprises the steps of proportioning according to target material components, carrying out arc melting on the prepared raw materials, compacting the crushed raw materials into a target by a press, and finally carrying out high-temperature annealing in a high-vacuum annealing furnace for 10-30min to obtain the target material. The sputtering temperature of the isolation layer is 450-650 ℃, and the sputtering target is preferably a Ta metal target.
The hard magnetic layer and the isolation layer can be repeatedly deposited as required, the thickness of each hard magnetic layer is reduced along with the increase of the number of the isolation layers under the condition of constant total thickness, the thickness of the hard magnetic layer is preferably 1 mu m, the thickness of the isolation layer is preferably 9nm, and the repeated deposition can be up to tens of micrometers in consideration of comprehensive growth efficiency and performance.
In the step 3), the sputtering temperature is 200-300 ℃, and the thickness is increased along with the increase of the total thickness of the hard magnetic layer and is not less than 100nm.
The beneficial effects of the invention are as follows:
according to the invention, the NdFeB-based single-layer thick film is changed into the NdFeB-based multi-layer thick film by inserting the isolating layer in the growing process of the NdFeB-based thick film, so that the perpendicular magnetic anisotropy and the binding force are enhanced. The high-melting point non-ferromagnetic metal isolation layer not only can limit the movement of defects in the growing process of the NdFeB-based thick film and reduce the growth stress caused by the bombardment of a film by DC magnetron sputtering atoms so as to improve the bonding force, but also can construct a multi-layer film to enable crystals to migrate and diffuse again so as to enable crystal grains to compete with each other in the growing process of the film, different crystal grains have common preferred orientation of a vertical film surface, the formation of an out-of-plane texture of the NdFeB is induced so as to increase the vertical magnetic anisotropy of the NdFeB-based thick film, and meanwhile, the isolation layer can generate stress to promote the flow of an Nd-rich phase in the film layer, so that the NdFeB crystal grains are completely coated and the magnetic property is increased.
Drawings
FIG. 1 is a schematic diagram of the structure of an NdFeB-based multilayer thick film;
FIG. 2 is an in-plane external hysteresis loop of a multilayer thick film of Ta/(NdDyFeCoB/Ta) 5/NdDyFeCoB/Ta in example 1, in which the number of Ta barrier layers is 5 and the thickness is 3 nm;
FIG. 3 is an in-plane external hysteresis loop of a multilayer thick film of Ta/(NdDyFeCoB/Ta) 5/NdDyFeCoB/Ta in example 1 in which the number of Ta barrier layers is 5 and the thickness is 9 nm;
FIG. 4 is an in-plane external hysteresis loop of a multilayer thick film of Ta/(NdDyFeCoB/Ta) 11/NdDyFeCoB/Ta in example 2 in which the number of Ta barrier layers is 11 and the thickness is 9 nm;
FIG. 5 is an in-plane external hysteresis loop of a 6 μm thick Ta/NdDyFeCoB/Ta single layer thick film in comparative example 1;
FIG. 6 is an in-plane external hysteresis loop of thick films with and without Ta barrier layers of 15 μm thickness in example 4 and comparative example 2.
Detailed Description
The invention is further described below with reference to the accompanying drawings and examples, which are intended to facilitate an understanding of the invention without any limitation thereto.
As shown in fig. 1, a schematic structural diagram of the NdFeB-based multilayer thick film is shown in the following order from inside to outside: a substrate, a buffer layer, (hard layer/spacer) repeat unit, a hard layer and a cover layer.
Example 1:
in this embodiment, the substrate is a Si substrate, and the target is Nd 15 DyFe 65 Co 10 B 10 The total thickness of the prepared NdFeB-based multilayer thick film hard magnetic layer is about 6 mu m, the Ta isolating layer is uniformly inserted into the hard magnetic layer, and the number of layers is 5, namely, each 1 mu m NdDyFeCoB hard magnetic layer is inserted into one Ta isolating layer, and the total number of the Ta isolating layers is 5, and the number of the NdDyFeCoB hard magnetic layers is 6.
The preparation method of the NdFeB-based multilayer thick film comprises the following steps:
step (1): a layer of Ta with the thickness of 100nm is deposited on a Si substrate by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 25-300 ℃.
Step (2): a layer of NdDyFeCoB hard magnetic layer with the thickness of 1 μm is deposited on the buffer layer Ta by adopting a direct current magnetron sputtering method, and the sputtering temperature is 500 ℃.
Step (3): a layer of Ta with the thickness of 9nm is deposited on the hard magnetic layer NdDyFeCoB by adopting a direct current magnetron sputtering method to serve as an isolation layer, wherein the sputtering temperature is 500 ℃.
Step (4): repeating the step (2) and the step (3) for 4 times, and repeatedly growing an NdDyFeCoB hard magnetic layer and a Ta isolating layer; and finally repeating the step (2) once again to finish the growth of the last NdDyFeCoB hard magnetic layer.
Step (5): a layer of Ta with the thickness of 100nm is deposited on the last hard magnetic layer by adopting a direct current magnetron sputtering method, and the sputtering temperature is 200-300 ℃.
Step (6): the temperature was raised to 650 ℃ and annealed for 20min.
Wherein, the thickness change of the Ta isolating layer in the step (3) has a larger influence on the magnetic performance. When the Ta spacer thickness is 3nm and 6nm, the occurrence of the sagging in the hysteresis loop diagram should be caused by insufficient spacer thickness, not completely isolating the upper and lower layers. The Ta separation layer thicknesses were 1-1, 1-2 and 1-3 when 9nm, 15nm and 20nm, respectively.
FIG. 2 shows Ta/(NdDyFeCoB/Ta) at 5 layers of Ta separation layer thickness of 3nm 5 The in-plane and out-of-plane refer to the applied magnetic field directions parallel and perpendicular to the surface of the film being formed, respectively. The waist collapse is evident from the figure.
FIG. 3 shows Ta/(NdDyFeCoB/Ta) at 5 layers of Ta separation layer thickness of 9nm 5 Inner-surface external hysteresis loop of NdDyFeCoB/Ta multilayer thick film.
Example 2:
the preparation method of this example is basically the same as that of example 1, except that the number of Ta spacers is changed in that:
the thickness of the NdDyFeCoB hard magnetic layer in step (2) of example 1 was changed to 2 μm, 1 μm or 500nm.
The repetition number in step (4) of example 1 was changed to 1, 4 or 10 times for repeating step (2) and step (3).
The number of Ta barrier layers was 2, 5 and 11, respectively designated 2-1, 2-2 and 2-3.
FIG. 4 shows Ta/(NdDyFeCoB/Ta) for a layer thickness of 11 Ta spacer layers of about 9nm 11 Inner-surface external hysteresis loop of NdDyFeCoB/Ta multilayer thick film.
Comparative example 1:
in this comparative example, a Si substrate was used as the substrate and Nd was used as the target 15 DyFe 65 Co 10 B 10 Self-made alloy target (hereinafter referred to as NdDyFeCoB), ta metal target, and preparing a 6 μm thick NdFeB-based single-layer film.
The preparation method of the NdFeB-based single-layer thick film comprises the following steps:
step (1): a layer of Ta with the thickness of 100nm is deposited on a Si substrate by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 25-300 ℃.
Step (2): a layer of NdDyFeCoB hard magnetic layer with the thickness of 6 mu m is deposited on the buffer layer Ta by adopting a direct current magnetron sputtering method, and the sputtering temperature is 500 ℃.
Step (3): a layer of Ta with the thickness of 100nm is deposited on the hard magnetic layer by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 200-300 ℃.
Step (4): the temperature was raised to 650 ℃ and annealed in situ for 20min.
FIG. 4 shows the out-of-plane hysteresis loop for a 6 μm thick Ta/NdDyFeCoB/Ta single layer thick film.
Table 1 below shows the magnetic properties of NdFeB-based thick films prepared in example 1, example 2 and comparative example 1, in which the degree of squareness in the out-of-plane direction refers to the degree of squareness of the out-of-plane hysteresis loop, and the degree of squareness in the in-plane direction refers to the degree of squareness of the in-plane hysteresis loop, and the difference value can visually indicate the magnitude of perpendicular magnetic anisotropy, and the larger the difference value, the better the perpendicular magnetic anisotropy. It was revealed that the NdFeB-based multi-layer thick film having Ta barrier layer had stronger perpendicular magnetic anisotropy than the single-layer thick film, and the perpendicular magnetic anisotropy was continuously enhanced with an increase in Ta barrier layer thickness with the same number of barrier layers; at the same thickness, when the number of Ta spacer layers is sufficiently large (for example, when the number of spacer layers is 11 or more), perpendicular magnetic anisotropy is stronger. Meanwhile, it can be noted that the coercive force is not significantly changed in the process and is always maintained at a higher level (about 1.9T), indicating that the coercive force is not significantly affected.
TABLE 1 NdFeB-based Thick film magnetic Properties
Example 3
In this embodiment, the substrate is a Si substrate, and the target is Nd 15 DyFe 65 Co 10 B 10 Self-made alloy targets (hereinafter abbreviated as NdDyFeCoB), mo metal targets and W metal targets. The total thickness of the prepared NdFeB-based multi-layer thick film hard magnetic layer is about 6 mu m, mo or W isolating layers are uniformly inserted into the hard magnetic layer, the number of layers is 2, namely, each 2 mu m NdDyFeCoB hard magnetic layer is grown, one Mo or W isolating layer is inserted, and the total number of isolating layers is 2, and 3 NdDyFeCoB hard magnetic layers.
The preparation method of the NdFeB-based multilayer thick film comprises the following steps:
step (1): a layer of Ta with the thickness of 100nm is deposited on a Si substrate by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 25-300 ℃.
Step (2): a layer of NdDyFeCoB hard magnetic layer with the thickness of 2 mu m is deposited on the buffer layer Ta by adopting a direct current magnetron sputtering method, and the sputtering temperature is 500 ℃.
Step (3): a layer of 9nm Mo or W is deposited on the hard magnetic layer NdDyFeCoB by adopting a direct current magnetron sputtering method to serve as an isolation layer, wherein the sputtering temperature is 500 ℃.
Step (4): repeating the step (2) and the step (3) for 1 time, and repeatedly growing the hard magnetic layer and the isolation layer. And finally repeating the step (2) once again to finish the growth of the last NdDyFeCoB hard magnetic layer.
Step (5): a layer of Ta with the thickness of 100nm is deposited on the last hard magnetic layer by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 200-300 ℃.
Step (6): the temperature was raised to 650 ℃ and annealed for 20min.
The thick film using only the Mo isolation layer was recorded as 3-1, and the thick film using only the W isolation layer was recorded as 3-2.
Table 2 below shows the magnetic properties of the NdFeB-based thick films prepared in example 2-1, example 3-1 and example 3-2, showing that the Ta barrier layer enhances perpendicular magnetic anisotropy more than the Mo and W barrier layers.
TABLE 2 NdFeB-based Thick film magnetic Properties
| Rectangle degree in out-of-plane direction | Rectangle degree in-plane direction | Difference value | |
| Example 2-1 (Ta) | 0.801 | 0.606 | 0.195 |
| Example 3-1 (Mo) | 0.807 | 0.654 | 0.153 |
| Examples 3 to 2 (W) | 0.792 | 0.659 | 0.133 |
Example 4:
in order to find that the method is applicable to thicker thickness, in the embodiment, the substrate adopts a Si substrate, and the target adopts Nd 15 DyFe 65 Co 10 B 10 The total thickness of the prepared NdFeB-based multilayer thick film hard magnetic layer is about 15 mu m, the Ta isolating layer is uniformly inserted into the hard magnetic layer, and the number of layers is 14, namely, each 1 mu m NdDyFeCoB hard magnetic layer is inserted into one Ta isolating layer, and the total number of the Ta isolating layers is 14, and the number of NdDyFeCoB hard magnetic layers is 15.
The preparation method of the NdFeB-based multilayer thick film comprises the following steps:
step (1): a layer of Ta with the thickness of 200nm is deposited on a Si substrate by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 25-300 ℃.
Step (2): a layer of NdDyFeCoB hard magnetic layer with the thickness of 1 μm is deposited on the buffer layer Ta by adopting a direct current magnetron sputtering method, and the sputtering temperature is 500 ℃.
Step (3): a layer of Ta with the thickness of 9nm is deposited on the hard magnetic layer NdDyFeCoB by adopting a direct current magnetron sputtering method to serve as an isolation layer, wherein the sputtering temperature is 500 ℃.
Step (4): repeating the step (2) and the step (3) for 13 times, and repeatedly growing the NdDyFeCoB hard magnetic layer and the Ta isolating layer. And finally repeating the step (2) once again to finish the growth of the last NdDyFeCoB hard magnetic layer.
Step (5): a layer of Ta with the thickness of 200nm is deposited on the last hard magnetic layer by adopting a direct current magnetron sputtering method as a buffer layer, and the sputtering temperature is 200-300 ℃.
Step (6): the temperature was raised to 650 ℃ and annealed for 20min.
Comparative example 2:
this comparative example was substantially identical to the procedure of comparative example 1, except that the thickness of the NdDyFeCoB hard magnetic layer was changed to 15 μm.
FIG. 5 shows example 4 and comparative example2 Ta/(NdDyFeCoB/Ta) with Ta barrier layer of 15 μm thickness 14 An in-plane external hysteresis loop of the NdDyFeCoB/Ta thick film and the Ta/NdDyFeCoB/Ta thick film without the Ta isolating layer. It is evident that the NdFeB-based thick film with Ta barrier layer has better magnetic properties.
Table 3 below shows the magnetic properties of the NdFeB-based thick films prepared in example 4 and comparative example 2, showing that the NdFeB-based single layer thick film without the Ta barrier layer was nearly isotropic at a thickness of 15 μm, and the perpendicular magnetic anisotropy thereof was significantly enhanced to a higher level after insertion of the Ta barrier layer. Similarly, it was found that the coercivity of the NdFeB-based single layer thick film at 15 μm was significantly reduced by 1.52T compared to the previous level of about 1.9T, whereas the coercivity was restored to the previous level by 2.18T after the spacer layer was inserted. The method shows that the vertical magnetic anisotropy can be enhanced and the coercive force can be maintained at a higher level by inserting the Ta isolating layer in the growing process of the NdFeB-based permanent magnetic thick film, and the high-performance vertical magnetic anisotropy NdFeB-based permanent magnetic thick film with the thickness of tens of micrometers can be directly prepared by utilizing a magnetron sputtering method.
TABLE 3 NdFeB-based Thick film magnetic Properties
The invention is not a matter of the known technology.
The above embodiments are provided to illustrate the technical concept and features of the present invention and are intended to enable those skilled in the art to understand the content of the present invention and implement the same, and are not intended to limit the scope of the present invention. All equivalent changes or modifications made in accordance with the spirit of the present invention should be construed to be included in the scope of the present invention.
Claims (4)
1. A method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film is characterized by comprising the following steps: the perpendicular magnetic anisotropy of the NdFeB-based permanent magnet thick film is enhanced by inserting an isolating layer in the growing process of the NdFeB-based permanent magnet thick film; the NdFeB-based permanent magnet thick film contains a hard magnetic layer/isolation layer repeating unit, wherein the hard magnetic layer is a NdFeB-based rare earth permanent magnet material, the isolation layer is a high-melting-point nonferromagnetic metal, and a plurality of isolation layers are inserted; an isolating layer is inserted into each hard magnetic layer with the thickness of 1 mu m, and the preparation method of the NdFeB-based permanent magnet thick film comprises the following steps:
1) Buffer layer: directly depositing a buffer layer on a substrate by adopting a direct current magnetron sputtering method;
2) A hard layer/spacer repeat unit, a hard layer: depositing the hard magnetic layer on the buffer layer by adopting a direct current magnetron sputtering method, wherein the sputtering temperature is 450-650 ℃, and the thickness of each layer is 1-15 mu m; directly depositing an isolation layer on the hard magnetic layer by adopting a direct current magnetron sputtering method, wherein the sputtering temperature of the isolation layer is consistent with that of the hard magnetic layer, the isolation layer is deposited after cooling is not needed, and the thickness of each layer is 3-20nm; repeating the above operations to repeatedly grow the hard magnetic layer and the isolation layer to obtain a plurality of hard magnetic layer/isolation layer repeating units, and depositing a layer of hard magnetic layer on the last hard magnetic layer/isolation layer repeating unit;
3) And (3) covering layer: after the sputtering temperature is reduced, adopting a direct current magnetron sputtering method to directly deposit a cover layer on the last hard magnetic layer;
4) And (3) annealing: after the cover layer deposition is finished, raising the temperature to perform in-situ annealing, wherein the annealing temperature is 600-800 ℃ and the annealing time is 15-30min; the vertical magnetic anisotropy of the NdFeB-based permanent magnet thick film added with the isolating layer is improved by 3-5 times compared with that before;
the total thickness of the NdFeB-based permanent magnet thick film is 5-50 mu m.
2. The method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film according to claim 1, wherein: the isolating layer is one or more of Ta, mo, W, ti, hf.
3. The method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film according to claim 1, wherein: the substrate is Si substrate or SiO 2 A substrate or a pre-patterned Si substrate.
4. The method for enhancing the perpendicular magnetic anisotropy of an NdFeB-based permanent magnet thick film according to claim 1, wherein: in the step 1), the sputtering temperature is 25-300 ℃ and the thickness is not less than 100nm;
in the step 3), the sputtering temperature is 200-300 ℃ and the thickness is not less than 100nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210582217.2A CN115020099B (en) | 2022-05-26 | 2022-05-26 | Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210582217.2A CN115020099B (en) | 2022-05-26 | 2022-05-26 | Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115020099A CN115020099A (en) | 2022-09-06 |
| CN115020099B true CN115020099B (en) | 2023-11-03 |
Family
ID=83071131
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210582217.2A Active CN115020099B (en) | 2022-05-26 | 2022-05-26 | Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115020099B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1363101A (en) * | 2000-02-22 | 2002-08-07 | 住友特殊金属株式会社 | Thin permanent-magnet film and process for producing same |
| CN101615475A (en) * | 2009-05-08 | 2009-12-30 | 北京科技大学 | A kind of manufacture method of flexible anisotropic bonding rare earth permanent magnet |
| JP2012109490A (en) * | 2010-11-19 | 2012-06-07 | Hitachi Metals Ltd | Method for manufacturing rare earth permanent magnet thin film |
| CN104993046A (en) * | 2015-06-25 | 2015-10-21 | 华中科技大学 | MTJ unit and manufacturing method thereof |
| CN113549884A (en) * | 2021-06-24 | 2021-10-26 | 广东麦格智芯精密仪器有限公司 | Preparation method of magnetic film with perpendicular magnetic anisotropy and magnetic film |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1218331C (en) * | 2000-08-02 | 2005-09-07 | 株式会社新王磁材 | Thin film rare earth permanent magnet, and method for mfg. same |
-
2022
- 2022-05-26 CN CN202210582217.2A patent/CN115020099B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1363101A (en) * | 2000-02-22 | 2002-08-07 | 住友特殊金属株式会社 | Thin permanent-magnet film and process for producing same |
| CN101615475A (en) * | 2009-05-08 | 2009-12-30 | 北京科技大学 | A kind of manufacture method of flexible anisotropic bonding rare earth permanent magnet |
| JP2012109490A (en) * | 2010-11-19 | 2012-06-07 | Hitachi Metals Ltd | Method for manufacturing rare earth permanent magnet thin film |
| CN104993046A (en) * | 2015-06-25 | 2015-10-21 | 华中科技大学 | MTJ unit and manufacturing method thereof |
| CN113549884A (en) * | 2021-06-24 | 2021-10-26 | 广东麦格智芯精密仪器有限公司 | Preparation method of magnetic film with perpendicular magnetic anisotropy and magnetic film |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115020099A (en) | 2022-09-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Chen | Recent progress of grain boundary diffusion process of Nd-Fe-B magnets | |
| KR101243347B1 (en) | R-Fe-B Sintered magnet with enhancing mechanical property and fabrication method thereof | |
| CN107424695B (en) | Double-alloy nanocrystalline rare earth permanent magnet and preparation method thereof | |
| JP5370609B1 (en) | R-T-B permanent magnet | |
| JP5565499B1 (en) | R-T-B permanent magnet | |
| WO2005091315A1 (en) | R-Fe-B BASED THIN FILM MAGNET AND METHOD FOR PREPARATION THEREOF | |
| CN107123497B (en) | High-temperature stability permanent magnetic material and application thereof | |
| JP4337209B2 (en) | Permanent magnet thin film and manufacturing method thereof | |
| EP1329912B1 (en) | Thin film rare earth permanent magnet, and method for manufacturing the permanent magnet | |
| CN115020099B (en) | Method for enhancing vertical magnetic anisotropy of NdFeB-based permanent magnet thick film | |
| JP5565498B1 (en) | R-T-B permanent magnet | |
| CN102436887B (en) | Anisotropic nano-crystalline composite permanent magnetic material and preparation method thereof | |
| JP5565497B1 (en) | R-T-B permanent magnet | |
| WO2014038022A1 (en) | Nd-Fe-B THIN FILM MAGNET, AND METHOD FOR PRODUCING SAME | |
| JPH0616445B2 (en) | Permanent magnet material and manufacturing method thereof | |
| CN1204571C (en) | Nano composite rare earth permanent magnet film material and its preparation method | |
| JP6398911B2 (en) | Permanent magnet and method for manufacturing the same | |
| KR101341344B1 (en) | R-Fe-B Sintered magnet with enhanced coercivity and fabrication method thereof | |
| CN105655074A (en) | Permanent magnet material with positive temperature coefficient and application thereof | |
| Tian et al. | Fabrication of high coercive Nd–Fe–B based thin films through annealing Nd–Fe–B/Nd–Fe multilayers | |
| CN110735119B (en) | Method for preparing huge coercive force Mn3Ga film through magnetron sputtering | |
| CN114999801B (en) | Method for improving coercive force of NdFeB-based permanent magnetic thick film | |
| Pan et al. | Hot-Roll Fabrication of Anisotropic Nanograin Nd-Fe-B Magnet | |
| CN116313475A (en) | Method for simultaneously improving residual magnetization and coercive force of micron NdFeB-based permanent magnetic film | |
| CN109637768A (en) | A kind of rare earth permanent-magnetic material and preparation method thereof containing yttrium |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |