Information storage device for non-volatile regulation and control of vertical magnetic moment flipping in electric field and preparation method of information storage device

Abstract

The invention discloses an information storage device for non-volatile regulation and control of vertical magnetic moment flipping in an electric field and a preparation method of the information storage device. The information storage device is provided with a multi-layer composite film structure, and the multi-layer composite film structure is formed by sequentially overlapping a bottom electrode layer, a ferroelectric layer, a seed layer, a ferromagnetic layer, a protective layer and a top electrode layer; and the ferromagnetic layer is made of a rare earth-transition metal amorphous alloy material doped with an Mn element. According to the information storage device, Mn-doped rare earth-transition metal amorphous alloy is grown on a ferroelectric layer, and non-volatile regulation and control of tunnel magnetoresistance by an electric field at room temperature and a low magnetic field are realized by utilizing a magnetoelectric coupling effect; the problems of low temperature, large magnetic field assistance, volatility, need of a large electric field and the like of vertical regulation and control of an existing electric field are solved, the method is operated at room temperature or near room temperature, only a small magnetic field assistance is needed, and the method has the advantages of non-volatility, low overturning electric field, low power consumption and the like.

Description

Technical Field

[0001] The present invention belongs to the fields of information storage technology and materials, and more particularly relates to an information storage device for electrically non-volatile regulation of perpendicular magnetic moment reversal and a preparation method thereof. Background Art

[0002] With the development of human information technology and science and technology, the demand for information storage and computing by people is increasing day by day. However, due to approaching the physical limit, traditional silicon-based semiconductor technology faces insurmountable challenges in miniaturization of size and power consumption. At the same time, traditional semiconductor technology adopts the von Neumann architecture, and a memory wall will be generated due to the separation of storage and computing. Therefore, finding a new type of non-volatile storage technology with high density, high speed, low power consumption and small size is a direction that people widely focus on. Among them, spin-based logic and storage devices have achieved rapid development in recent years, and a core problem in this field is how to efficiently implement the operation and reversal of magnetic moments.

[0003] Reversing the perpendicular magnetic moment by electrical means is crucial for the development of spin storage and logic devices with advantages such as fast read and write, high storage density, high cycle times and non-volatility. Due to the inverse coupling of ferroelectricity and ferromagnetism, realizing the reversal of magnetic moments by an electric field still faces challenges. Currently, the reversal of the perpendicular magnetic moment utilizes the Oersted field, spin transfer torque and spin-orbit torque generated by current, which requires a large current density, and thus the writing power consumption is large. The existing few strategies for electrically regulating the perpendicular magnetic moment still have problems such as low temperature, the need for large magnetic field assistance, volatility, and the need for a large electric field. Reversing the perpendicular magnetic moment by an electric field to write information can effectively reduce the power consumption and has great potential application prospects. Summary of the Invention

[0004] Aiming at the defects existing in the prior art, the purpose of the present invention is to provide a new type of information storage device for electrically non-volatile regulation of perpendicular magnetic moment reversal. This device only requires a very low auxiliary magnetic field, and can still achieve non-volatile reversal under the volatile piezoelectric strain. At the same time, the reversal voltage is low, the reversal power consumption is small, and the working temperature can reach room temperature.

[0005] The information storage device for electrically non-volatile regulation of perpendicular magnetic moment reversal provided by the present invention has a multi-layer composite film structure, and the multi-layer composite film structure is formed by sequentially stacking a bottom electrode layer, a ferroelectric layer, a seed layer, a ferrimagnetic layer, a protective layer and a top electrode layer; wherein, the ferroelectric layer is formed on the bottom electrode layer; the seed layer is formed on the ferroelectric layer; the ferrimagnetic layer is formed on the seed layer; the protective layer is formed on the ferrimagnetic layer to protect the ferrimagnetic layer from being oxidized; the top electrode layer is formed on the protective layer.

[0006] Further, the ferrimagnetic layer is made of a rare-earth-transition metal amorphous alloy material doped with Mn element, wherein the rare-earth element includes at least one of the following: Gd, Tb, Dy, Ho, Er, Tm, and the atomic mass content of the rare-earth element includes but is not limited to 15% - 40%, such as 21% or 22% specifically, and the transition metal element includes at least one of the following: Fe, Co, Ni, and the atomic mass content of the transition metal element includes but is not limited to 55% - 80%, such as 66%, 67% or 69% specifically. This material has strong perpendicular magnetic anisotropy and the characteristic of low coercivity near the magnetic compensation temperature.

[0007] Furthermore, the doping amount of Mn in the rare-earth-transition metal amorphous alloy material doped with Mn element includes but is not limited to 5% - 15%, such as 10% or 12% specifically.

[0008] According to an embodiment of the present invention, the rare-earth-transition metal amorphous alloy material doped with Mn element is gadolinium iron manganese (Gd 21 Fe 69 Mn 10 , where the subscript numbers represent atomic percentages) ternary alloy.

[0009] According to an embodiment of the present invention, the rare-earth-transition metal amorphous alloy material doped with Mn element is gadolinium iron manganese (Gd 22 Fe 66 Mn 12 , where the subscript numbers represent atomic percentages) ternary alloy.

[0010] According to an embodiment of the present invention, the rare-earth-transition metal amorphous alloy material doped with Mn element is gadolinium iron manganese (Gd 21 Fe 67 Mn 12 , where the subscript numbers represent atomic percentages) ternary alloy.

[0011] Further, the bottom electrode layer and the seed layer serve as the positive and negative electrodes of the ferroelectric layer respectively, and an electric field is applied to the ferroelectric layer, and the direction of the electric field is perpendicular to the ferroelectric layer; under the action of the electric field, the ferroelectric layer changes the magnetic compensation temperature of the ferrimagnetic layer through the magnetoelectric coupling effect, and then with the assistance of a low constant auxiliary magnetic field not higher than 3 mT, the magnetic moment of the transition metal element in the ferrimagnetic layer undergoes a 180° flip.

[0012] Further, at room temperature or near room temperature (270 - 330 K), the ferroelectric layer can also achieve non-volatile magnetic moment flipping with the help of a suitable auxiliary magnetic field by using linear piezoelectric strain.

[0013] The "suitable auxiliary magnetic field" here means that the auxiliary magnetic field should neither be too large nor too small. If it is too small, such as less than 1 mT, magnetic moment flipping may not occur. If it is too large, such as higher than 10 mT, the flipping may be volatile. There is an interval for the magnetic field to achieve non-volatile flipping, and this interval is related to the ambient temperature and sample composition.

[0014] Furthermore, the seed layer, the ferrimagnetic layer, and the protective layer are in the shape of a Hall bar. The dimensions of the Hall bar include but are not limited to a channel length of 50 µm to 500 µm (specifically, such as 50 µm or 120 µm) and a channel width of 0.2 µm to 1 mm (specifically, such as 0.4 µm or 20 µm). The top electrode layer serves as the electrode of the Hall bar to detect the magnetic moment of transition metal elements by measuring the anomalous Hall effect.

[0015] Even further, the material for forming the bottom electrode layer can be a conductive metal material, specifically such as: platinum (Pt), copper (Cu), gold (Au), and aluminum (Al); and the material for forming the seed layer can be a non-oxide material, specifically such as: tantalum (Ta), platinum (Pt), copper (Cu), titanium (Ti); and the material for forming the ferroelectric layer can be a piezoelectric material, specifically such as: crystals of lead magnesium niobate titanate, crystals of barium titanate; and the material for forming the protective layer can be a non-oxide material, specifically such as: tantalum (Ta), platinum (Pt), copper (Cu), titanium (Ti); and the material for forming the top electrode layer can be a non-oxide material, specifically such as: titanium (Ti), platinum (Pt), copper (Cu), gold (Au), and aluminum (Al).

[0016] The lead magnesium niobate-lead titanate [(1-x)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPbTiO3 (PMN-xPT)], where x refers to the content of PbTiO3 in the crystal, and its value can be 27% to 35%.

[0017] According to an embodiment of the present invention, the material for forming the ferroelectric layer can be a crystal of lead magnesium niobate titanate (Pb(Mg 1 / 3Nb 2 / 3 ) 0.7 Ti 0.3 O3, hereinafter referred to as PMN-PT).

[0018] Even further, the size of the ferroelectric layer is equal to the size of the bottom electrode layer; the size of the bottom electrode layer is larger than that of the seed layer, the ferrimagnetic layer, the protective layer, or the top electrode layer.

[0019] Further, the thickness of the bottom electrode layer can be 0.2 - 1000 nm, specifically 60 nm; the thickness of the ferroelectric layer can be 1 μm - 10 mm, specifically 0.5 mm or 0.3 mm; the thickness of the seed layer can be 0.2 - 100 nm, specifically 1 nm or 4 nm; the thickness of the ferrimagnetic layer can be 2 - 100 nm, specifically 6 nm or 10 nm; the thickness of the protective layer can be 1 - 100 nm, specifically 2 nm or 3 nm; the thickness of the top electrode layer is 0.2 - 1000 nm, specifically 64 nm.

[0020] According to an embodiment of the present invention, the size of the ferroelectric layer is length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5 × 5 × 0.5 mm, and can be reasonably changed according to actual needs.

[0021] According to an embodiment of the present invention, the size (length × width) of the ferroelectric layer can be equal to the size (length × width) of the bottom electrode layer.

[0022] The present invention also provides a method for preparing the above-mentioned information storage device for electrically non-volatile control of magnetic moment reversal.

[0023] The method for preparing the information storage device for electrically non-volatile control of magnetic moment reversal provided by the present invention is prepared by physical vapor deposition, and the physical vapor deposition method includes magnetron sputtering or evaporation.

[0024] When prepared by magnetron sputtering, it specifically includes the following steps: (1) Prepare a ferroelectric layer and polish one of its surfaces. (2) Prepare a bottom electrode on the unpolished surface of the ferroelectric layer by magnetron sputtering. (3) Sequentially magnetron sputter to prepare a seed layer, a ferrimagnetic layer, and a protective layer on the polished surface of the ferroelectric layer. (4) Microfabricate the multilayer film composed of the seed layer, the ferrimagnetic layer, and the protective layer into a Hall bar structure by photolithography for the sample grown in steps (2) and (3), and then use the lift-off process and magnetron sputtering method to lead out the top electrode from the Hall bar.

[0025] According to an embodiment of the present invention, the material for forming the ferroelectric layer can be lead magnesium niobate titanate (Pb(Mg 1 / 3Nb 2 / 3 ) 0.7 Ti 0.3A crystal of O3). The crystal of PMN-PT is processed into a ferroelectric layer with the size of length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5×5×0.5 mm, which can be reasonably changed according to actual needs. Then, single-sided (001) surface polishing is carried out, and the required roughness is less than 1 nm.

[0026] In the above method, the process parameters of the magnetron sputtering are as follows: using an ultra-high vacuum system at room temperature, pumping the background vacuum to below 10 -7 Torr, and then introducing argon. The growth pressure is 3 - 5 mTorr, but not limited to this.

[0027] In the above method, for the Hall bar structure, the channel width is 0.2 µm - 1 mm (specifically, such as 20 µm or 0.4 µm), but not limited to this, and the channel length is 50 µm - 500 µm (specifically, such as 50 µm or 120 µm), but not limited to this.

[0028] Compared with the prior art, the present invention has the following beneficial effects: This information storage device grows a Mn-doped rare earth-transition metal amorphous alloy on a ferroelectric layer and utilizes the magnetoelectric coupling effect to achieve non-volatile regulation of the tunneling magnetoresistance by an electric field at room temperature and low magnetic fields; it overcomes the problems existing in the existing electric field regulation of perpendicularity, such as low temperature, large magnetic field assistance, volatility, and the need for a large electric field. The present invention operates at room temperature or near room temperature, only requires an external small magnetic field assistance, has non-volatility, a low switching electric field, and low power consumption. Brief Description of the Drawings

[0029] Figure 1 It is a schematic structural diagram of an information storage device for non-volatile regulation of the perpendicular magnetic moment flip by an electric field.

[0030] Figure 2 It is the coercivity-temperature curve near the compensation temperature of the GdFeMn thin film and other binary alloy thin films.

[0031] Figure 3 It is the regulation behavior of the anomalous Hall resistance under different electric fields at near room temperature.

[0032] Figure 4 It is the volatile strain curve of the ferroelectric layer and the magnetic compensation temperature under different voltages.

[0033] Figure 5 It is the non-volatile regulation of the anomalous Hall resistance by an electric field under a near-room-temperature constant low auxiliary magnetic field.

[0034] Figure 6 It is the coercivity-temperature curve of the information storage devices prepared from GdFeMn ternary ferrimagnets with different component ratios.

[0035] Description of the reference numerals: 1 - bottom electrode layer, 2 - ferroelectric layer, 3 - seed layer, 4 - ferrimagnetic layer, 5 - protective layer, 6 - top electrode layer. Detailed implementation manners

[0036] The present invention will be further described in detail below in conjunction with the detailed implementation manners. The provided embodiments are only for clarifying the present invention, rather than limiting the scope of the present invention. The following provided embodiments can be used as a guide for those of ordinary skill in the art to make further improvements, and do not limit the present invention in any way.

[0037] The experimental methods in the following embodiments are all conventional methods unless otherwise specified, and are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified.

[0038] An information storage device for non-volatile electric-field regulation of perpendicular magnetic moment reversal proposed by the present invention has a structure as Figure 1 shown, a multi-layer composite thin film structure formed by sequentially stacking a bottom electrode layer 1, a ferroelectric layer 2, a seed layer 3, a ferrimagnetic layer 4, a protective layer 5, and a top electrode layer 6.

[0039] The bottom electrode layer 1 and the seed layer 3 serve as the positive and negative electrodes of the ferroelectric layer 2 respectively, and an electric field is applied thereto, wherein the direction of the electric field is perpendicular to the ferroelectric layer 2. The ferrimagnetic layer 4 is made of a rare-earth-transition metal amorphous alloy material doped with Mn element. The protective layer 5 is used to protect the ferrimagnetic layer 4 from oxidation. The seed layer 3, the ferrimagnetic layer 4, and the protective layer 5 are made into a Hall bar shape by photolithography, and the top electrode layer 6 serves as the electrode of the Hall bar to measure the anomalous Hall resistance. The ferroelectric layer 2 can generate linear volatile strain under the action of the electric field, and the strain is transmitted to the ferrimagnetic layer thereon. The magnetic compensation temperature of the ferrimagnetic layer 4 is changed through the magnetoelectric coupling effect, and the sublattice magnetic moment of the ferrimagnetic layer 4 undergoes a 180° perpendicular reversal under a low auxiliary magnetic field, so that the anomalous Hall resistance is non-volatilely regulated.

[0040] The preparation process of the information storage device for non-volatile electric-field regulation of tunneling magnetoresistance proposed by the present invention can adopt magnetron sputtering method, including the following steps: (1) Using lead magnesium niobate titanate (Pb(Mg 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3A crystal of lead magnesium niobate titanate (Pb(Mg 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3, hereinafter referred to as PMN-PT) is processed into a ferroelectric layer 2 with the size of the ferroelectric layer being length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5×5×0.5 mm, and can be reasonably changed according to actual needs. Then, single-sided (001) surface polishing is carried out, and the roughness is required to be less than 1 nm.

[0041] (2) By using the magnetron sputtering method, a 60-nm platinum layer (Pt) is sputtered on the unpolished surface of the ferroelectric substrate as the bottom electrode, and can be reasonably changed according to actual needs.

[0042] (3) By using the magnetron sputtering method, a seed layer 3, a ferromagnetic layer 4, and a protective layer 5 are sequentially sputtered on the polished surface of the ferroelectric substrate. The process parameters of magnetron sputtering are as follows: at room temperature, an ultra-high vacuum system is used to pump the background vacuum to below 10 -7 Torr, and then argon is introduced, and the growth gas pressure is 4 mTorr or more (but not limited to this). The materials of each layer are selected as follows: the seed layer 3 uses (but not limited to) 4-nm tantalum (Ta), the ferromagnetic layer 4 preferably uses (but not limited to) a 6-nm gadolinium iron manganese (Gd 21 Fe 69 Mn 10 (the subscript numbers represent atomic percentages) ternary alloy, which is grown by a three-target co-sputtering process, and the protective layer 5 uses (but not limited to) 3-nm tantalum (Ta).

[0043] (4) The grown sample is microfabricated into a Hall bar structure for the magnetic tunnel junction by photolithography technology. The channel width is 20 μm or more (but not limited to this), and then the top electrode 6 is led out from the Hall bar by a lift-off process and the magnetron sputtering method. The top electrode layer 6 uses (but not limited to) 4-nm titanium (Ti) and 60-nm platinum (Pt) in sequence.

[0044] Example 1: Preparation of an information storage device with electrically non-volatile control of perpendicular magnetic moment reversal This information storage device is as Figure 1 shown.

[0045] A crystal of lead magnesium niobate titanate (Pb(Mg 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3, hereinafter referred to as PMN-PT) is processed into a ferroelectric layer 2 with the size of the ferroelectric layer substrate being length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5×5×0.5 mm. Then, single-sided (001) surface polishing is carried out, and the roughness is required to be less than 1 nm.

[0046] Using the magnetron sputtering method, a 60-nanometer platinum layer (Pt) was sputtered on the unpolished surface of the ferroelectric substrate as the bottom electrode layer 1.

[0047] Using the magnetron sputtering method, a seed layer 3, a ferromagnetic layer 4, and a protective layer 5 were successively sputtered on the polished surface of the ferroelectric substrate. The materials for each layer were selected as follows: the seed layer 3 used 4 nanometers of tantalum (Ta); the ferromagnetic layer 4 was made of a 6-nanometer gadolinium iron manganese (Gd 21 Fe 69 Mn 10 ) ternary alloy, grown by a three-target co-sputtering process; the protective layer 5 used 3 nanometers of tantalum (Ta).

[0048] The process parameters of magnetron sputtering were as follows: using an ultra-high vacuum system at room temperature, the background vacuum was pumped down to below 10 -7 Torr, and then argon gas was introduced, and the growth pressure was 4 mTorr.

[0049] The grown samples were microfabricated into Hall bar structures (with a channel width of 20 micrometers and a length of 120 micrometers) for magnetic tunnel junctions through photolithography technology, and then the top electrode 6 (using 4 nanometers of titanium (Ti) and 60 nanometers of platinum (Pt) successively deposited by magnetron sputtering) was led out from the Hall bar using the lift-off process and the magnetron sputtering method.

[0050] Comparative Example 1 The material of the ferromagnetic layer in Example 1 was replaced with gadolinium iron (Gd 27 Fe 73 ), and the comparative sample 1 was prepared according to the method of Example 1 under the remaining conditions.

[0051] Comparative Example 2 The material of the ferromagnetic layer in Example 1 was replaced with terbium iron (Tb 28 Fe 72 ), and the comparative sample 2 was prepared according to the method of Example 1 under the remaining conditions.

[0052] The well-prepared samples of Example 1, Comparative Example 1, and Comparative Example 2 were used to obtain the coercivity by measuring the loop of the anomalous Hall resistance versus magnetic field (abbreviated as the AHE loop) using a physical property measurement system instrument. As Figure 2 shown by the temperature-dependent coercivity curve, the coercivity of the manganese-doped gadolinium iron manganese (Gd 21 Fe 69 Mn 10 ) is 1 to 2 orders of magnitude lower than that of gadolinium iron (Gd 27 Fe 73 ) and terbium iron (Tb 28 Fe 72 ) near the compensation temperature. Gadolinium iron manganese (Gd 21 Fe 69 Mn 10The property of low coercivity is the key to being able to flip with only a low auxiliary magnetic field.

[0053] Measure the anomalous Hall effect (AHE) loop of gadolinium iron manganese (Gd 21 Fe 69 Mn 10 ) at different applied electric fields near the magnetic compensation temperature, and the results are as Figure 3 shown. After applying a voltage of -150 V, the polarity of the AHE loop is clockwise, indicating that the Gd magnetic moment is dominant. After applying a voltage of 50 V, the polarity of the AHE loop changes, and at this time the Fe magnetic moment is dominant. The AHE loops after removing the -150 V and removing the 50 V voltage have the same shape, indicating that the electric field's regulation of the AHE loop is volatile. Further, Figure 4 shows the strain-voltage curve of ferroelectric layer 2 and the curve of the compensation temperature of Gd 21 Fe 69 Mn 10 thin film varying with voltage. In the voltage range from -200 V to 50 V, the strain varies linearly with the voltage. In addition, the compensation temperature also varies basically linearly with the voltage. This also proves that the electric field's regulation of the compensation temperature of Gd 21 Fe 69 Mn 10 thin film is volatile. Then, apply different voltages to ferroelectric layer 2 at a constant temperature (325 K) and a constant magnetic field (-5 mT). The anomalous Hall resistance of the thin film changes in value corresponding to the magnetic field flip, and can still maintain to a certain extent the magnitude of the voltage when the voltage is removed, as Figure 5 shown. This means that this device can use the electric field to non-volatily regulate the vertical magnetic moment flip.

[0054] Example 2: Preparation of an information storage device with non-volatile electric field regulation of vertical magnetic moment flip Use a crystal of lead magnesium niobate titanate (Pb(Mg 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3, hereinafter referred to as PMN-PT). Process this crystal into a ferroelectric layer 2, and make the size of the ferroelectric layer substrate length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5 × 5 × 0.3 mm. Then perform single-sided (001) surface polishing, requiring the roughness to be less than 1 nm.

[0055] Use the magnetron sputtering method to sputter a 60-nanometer platinum layer (Pt) on the unpolished surface of the ferroelectric layer substrate as the bottom electrode layer 1.

[0056] Using the magnetron sputtering method, a seed layer 3, a ferrimagnetic layer 4, and a protective layer 5 are sequentially sputtered on the polished surface of the ferroelectric substrate. The materials for each layer are selected as follows: the seed layer 3 uses 1 nanometer of tantalum (Ta); the ferrimagnetic layer 4 uses a 10-nanometer gadolinium-iron-manganese (Gd 22 Fe 66 Mn 12 ), ternary alloy, which is grown by a three-target co-sputtering process; the protective layer 5 uses 2 nanometers of tantalum (Ta).

[0057] The process parameters of magnetron sputtering are as follows: using an ultra-high vacuum system at room temperature, the background vacuum is pumped down to 10 -7 Torr or less, and then argon gas is introduced, and the growth pressure is 3 mTorr.

[0058] The grown sample is microfabricated into a Hall bar structure (with a channel width of 20 microns and a length of 120 microns) for the magnetic tunnel junction by photolithography technology, and then the top electrode 6 (using 4 nanometers of titanium (Ti) and 60 nanometers of platinum (Pt) deposited by sequential magnetron sputtering) is led out from the Hall bar by the lift-off process and the magnetron sputtering method.

[0059] Example 3: Preparation of an information storage device with electrically non-volatile control of perpendicular magnetic moment reversal Using a lead magnesium niobate titanate (Pb(Mg 1 / 3 Nb 2 / 3 ) 0.67 Ti 0.33 O3, hereinafter referred to as PMN-PT) crystal, the crystal is processed into a ferroelectric layer 2, and the size of the ferroelectric layer substrate is length (along the

[100] direction) × width (along the

[010] direction) × thickness (along the

[001] direction) equal to 5 × 5 × 0.5 mm. Then, single-sided (001) surface polishing is carried out, and the roughness is required to be less than 1 nanometer.

[0060] Using the magnetron sputtering method, a 60-nanometer copper layer (Cu) is sputtered on the unpolished surface of the ferroelectric layer substrate as the bottom electrode layer 1.

[0061] Using the magnetron sputtering method, a seed layer 3, a ferrimagnetic layer 4, and a protective layer 5 are sequentially sputtered on the polished surface of the ferroelectric substrate. The materials for each layer are selected as follows: the seed layer 3 uses 4 nanometers of tantalum (Ta); the ferrimagnetic layer 4 uses a 6-nanometer gadolinium-iron-manganese (Gd 21 Fe 69 Mn 10 ), ternary alloy, which is grown by a three-target co-sputtering process; the protective layer 5 uses 3 nanometers of tantalum (Ta) The seed layer 3 uses 4 nanometers of tantalum (Ta). Using an ultra-high vacuum system at room temperature, the background vacuum is pumped down to 10 - 7Below Torr, then argon is introduced, and the growth pressure is 4 mTorr. The materials for each layer are selected as follows: The seed layer 3 uses 4 nm tantalum (Ta), and the ferrimagnetic layer 4 uses a ternary alloy of 6 nm gadolinium iron manganese (Gd 21 Fe 67 Mn 12 ), which is grown by a three-target co-sputtering process. The protective layer 5 uses 3 nm tantalum (Ta). After microfabrication, the top electrode layer 6 uses 4 nm titanium (Ti) and 60 nm copper (Cu).

[0062] The grown sample is microfabricated into a Hall bar structure (with a channel width of 0.4 μm and a length of 50 μm) for the magnetic tunnel junction by photolithography technology. Then, the top electrode 6 is led out from the Hall bar by a lift-off process and magnetron sputtering method (4 nm titanium (Ti) and 60 nm copper (Cu) are deposited by magnetron sputtering in sequence).

[0063] Example 4: Preparation of an information storage device with electrically non-volatile control of vertical magnetic moment reversal Basically the same as Example 1, the difference is that: the material of the ferrimagnetic layer in Example 1 is replaced with Gd 22 Fe 66 Mn 12 .

[0064] Example 5: Preparation of an information storage device with electrically non-volatile control of vertical magnetic moment reversal Basically the same as Example 1, the difference is that: the material of the ferrimagnetic layer in Example 1 is replaced with Gd 21 Fe 67 Mn 12 .

[0065] The devices prepared in Example 1, Example 4, and Example 5 are used to measure the AHE loops at different test temperatures by a physical property measurement system instrument to obtain the coercivity. The results are shown in Figure 6 . It can be seen from Figure 6 that the coercivity of GdFeMn thin films with different compositions can be as low as 10 mT in the range of about 3 K above and below the compensation temperature. Since the electric field can regulate the compensation temperature of the thin film by 5 - 6 K (as shown in Figure 4 ), this means that different GdFeMn thin films in the said composition range can all achieve electrically controlled magnetic moment reversal as low as 10 mT (specifically such as 3 mT).

[0066] The above has described the present invention in detail. For those skilled in the art, without departing from the gist and scope of the present invention and without the need for unnecessary experiments, the present invention can be implemented within a relatively wide range under equivalent parameters, concentrations, and conditions. Although specific embodiments of the present invention are given, it should be understood that the present invention can be further improved. In short, according to the principle of the present invention, this application intends to cover any modifications, uses, or improvements of the present invention, including those that depart from the scope disclosed in this application and are made using conventional techniques known in the art. Some basic features can be applied within the scope of the following appended claims.

Claims

1. An information storage device for electrically field non-volatile regulation of perpendicular magnetic moment reversal, having a multi-layer composite film structure, characterized in that: The multi-layer composite film structure is formed by sequentially stacking a bottom electrode layer, a ferroelectric layer, a seed layer, a ferrimagnetic layer, a protective layer, and a top electrode layer; wherein, the ferroelectric layer is formed on the bottom electrode layer; the seed layer is formed on the ferroelectric layer; the ferrimagnetic layer is formed on the seed layer; the protective layer is formed on the ferrimagnetic layer to protect the ferrimagnetic layer from being oxidized; the top electrode layer is formed on the protective layer; The ferrimagnetic layer is made of a rare-earth-transition metal amorphous alloy material doped with Mn element.

2. The information storage device for regulating the perpendicular magnetic moment reversal by the electric field according to claim 1, wherein: In the rare-earth-transition metal amorphous alloy material doped with Mn element, the rare-earth element includes at least one of the following: Gd, Tb, Dy, Ho, Er, Tm, and the transition metal element includes at least one of the following: Fe, Co, Ni.

3. The information storage device for electrically field non-volatile regulation of perpendicular magnetic moment reversal according to claim 2, characterized in that: The rare-earth-transition metal amorphous alloy material doped with Mn element is a gadolinium-iron-manganese ternary alloy.

4. The information storage device for regulating the perpendicular magnetic moment reversal by the electric field according to any one of claims 1-3, characterized in that: The bottom electrode layer and the seed layer serve as the positive and negative electrodes of the ferroelectric layer respectively; an electric field is applied to the ferroelectric layer, and the direction of the electric field is perpendicular to the ferroelectric layer; the ferroelectric layer changes the magnetic compensation temperature of the ferrimagnetic layer through the magnetoelectric coupling effect under the action of the electric field, and then with the assistance of a low constant auxiliary magnetic field not higher than 3 mT, the magnetic moment of the transition metal element in the ferrimagnetic layer undergoes a 180° flip.

5. The information storage device for electrically-field non-volatile control of perpendicular magnetic moment reversal according to any one of claims 1 to 3, characterized in that: The ferroelectric layer realizes non-volatile magnetic moment flipping at 270 - 330 K under the assistance of a magnetic field using linear piezoelectric strain.

6. The information storage device for regulating the perpendicular magnetic moment reversal by an electric field according to any one of claims 1-5, characterized in that: The seed layer, the ferrimagnetic layer, and the protective layer are in the shape of Hall bars; the top electrode layer serves as the electrode of the Hall bar to detect the magnetic moment of the transition metal element by measuring the anomalous Hall effect.

7. The information storage device for regulating the perpendicular magnetic moment reversal by the electric field and being non-volatile according to any one of claims 1-6, wherein: The material forming the bottom electrode layer is a conductive metal material, including but not limited to: platinum (Pt), copper (Cu), gold (Au), aluminum (Al); and / or, the material forming the seed layer is a non-oxide material, including but not limited to: tantalum (Ta), platinum (Pt), copper (Cu), titanium (Ti); and / or, the material forming the ferroelectric layer is a piezoelectric material, including but not limited to: crystals of lead magnesium niobate titanate, crystals of barium titanate; and / or, the material forming the protective layer is a non-oxide material, including but not limited to: tantalum (Ta), platinum (Pt), copper (Cu), titanium (Ti); and / or, the material forming the top electrode layer is a non-oxide material, including but not limited to: titanium (Ti), platinum (Pt), copper (Cu), gold (Au), aluminum (Al).

8. The information storage device for electrically non-volatile regulation of perpendicular magnetic moment flipping according to any one of claims 1 - 7, characterized in that: The size of the ferroelectric layer is equal to the size of the bottom electrode layer; the size of the bottom electrode layer is larger than the seed layer, the ferrimagnetic layer, the protective layer, or the top electrode layer; And / or, the thickness of the bottom electrode layer is 0.2 - 1000 nm; and / or, the thickness of the ferroelectric layer is 1 μm - 10 mm; and / or, the thickness of the seed layer is 0.2 - 100 nm; and / or, the thickness of the ferrimagnetic layer is 2 - 100 nm; and / or, the thickness of the protective layer is 1 - 100 nm; and / or, the thickness of the top electrode layer is 0.2 - 1000 nm.

9. The method for preparing an information storage device for electrically non-volatile control of vertical magnetic moment reversal according to any one of claims 1 - 8, wherein the preparation process is carried out by physical vapor deposition, and the physical vapor deposition method includes magnetron sputtering or evaporation.

10. The preparation method according to claim 9, characterized in that: The physical vapor deposition method is magnetron sputtering. The method for preparing the information storage device for electrically non-volatile control of vertical magnetic moment reversal includes the following steps: (1) Prepare a ferroelectric layer and polish one of its surfaces. (2) Prepare a bottom electrode on the unpolished surface of the ferroelectric layer by magnetron sputtering. (3) Sequentially deposit a seed layer, a ferrimagnetic layer, and a protective layer on the polished surface of the ferroelectric layer by magnetron sputtering. (4) Microfabricate the multilayer film composed of the seed layer, the ferrimagnetic layer, and the protective layer into a Hall bar structure by photolithography for the sample after the growth in steps (2) and (3), and then use the lift-off process and magnetron sputtering to lead out the top electrode from the Hall bar. Furthermore, the process parameters of the magnetron sputtering are as follows: using an ultra-high vacuum system at room temperature, evacuating the background vacuum to below 10 -7 Torr, and then introducing argon. The growth pressure is 3 - 5 mTorr, but not limited to this range; Further, in step (1), a ferroelectric layer is prepared using a crystal of lead magnesium niobate titanate. The size of the ferroelectric layer is length (along the [100] direction) × width (along the [010] direction) × thickness (along the [001] direction) equal to 5 × 5 × 0.5 mm; then, single-sided (001) surface polishing is carried out, and the roughness is required to be less than 1 nm. And / or, in step (2), a 60-nm platinum layer (Pt) is sputtered as the bottom electrode on the unpolished surface of the ferroelectric layer by magnetron sputtering. And / or, in the step (3), the materials of each layer are selected as follows: the seed layer is made of 4-nanometer tantalum (Ta); the ferromagnetic layer 4 is made of a ternary alloy of 6-nanometer gadolinium iron manganese (Gd 21 Fe 69 Mn 10 , where the subscript numbers represent atomic percentages); the protective layer is made of 3-nanometer tantalum (Ta); And / or, in step (4), for the Hall bar structure, the channel width is not limited to 0.2 µm - 1 mm, and the channel length is not limited to 50 µm - 500 µm.

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