KR20190109874A - Skyrmion based spin synaptic devices and method of manufacturing the same - Google Patents

Abstract

Disclosed are a skyrmion-based spin synapse device and a manufacturing method thereof, capable of securing extremely low power, multilevel, and linearity through physical property control of a skyrmion. According to the present invention, the skyrmion-based spin synapse device comprises a heavy metal layer made of a heavy metal material, a free layer disposed on the heavy metal layer and made of a ferromagnetic material, and a tunneling barrier layer disposed on the free layer; and has a structure in which the heavy metal layer, the free layer, and the tunneling barrier layer are sequentially laminated.

Description

Scorpion-based spin synaptic device and its manufacturing method {SKYRMION BASED SPIN SYNAPTIC DEVICES AND METHOD OF MANUFACTURING THE SAME}

The present invention relates to a scumion-based spin synaptic device and a method of manufacturing the same, and more particularly, to a scumion-based spin synaptic device and a method for manufacturing the same, which can secure extremely low power, multi-valued, and linearity through control of the property of the cumumion. It is about.

The human brain processes and stores a lot of information simultaneously and instantly, with more than 100 billion nerve cells signaling to and from other neurons with very little power through a synaptic link. Against this background, recently, studies are being actively conducted to emulate artificial intelligence (AI) that can sense, perceive, and interact with the human brain.

To mimic analog synaptic behavior, a physical object is required. Recently, synaptic devices using domain wall control through spin transfer torque (STT) in spin materials have been proposed.

However, the magnetic domain wall-based spin synaptic element is not stable in each state, the movement of the magnetic domain wall is not easy to control, and the generation of the magnetic domain wall occurs at various points. Access to the device is expected to have limitations.

In addition, the electric method of manipulating a magnetic object (formerly magnetic domain wall), which is a basic information unit of synapses, has been dependent on the spin transfer torque (STT). However, since the spin transfer torque has a large driving current, the device manipulation method using the conventional spin transfer torque is not a breakthrough method that goes beyond the conventional research method.

Related prior art documents are Korean Patent Publication No. 10-1588980 (January 27, 2016.), which discloses a synaptic device and a method of manufacturing the same for neuromorphic system applications.

It is an object of the present invention to provide a skumion-based spin synaptic device and a method of manufacturing the same, which can secure extremely low power, multi-valued, and linearity through control of the properties of scumion.

According to one or more embodiments of the present invention, a skimion-based spin synapse device may include a heavy metal layer made of a heavy metal material; A free layer disposed on the heavy metal layer and made of a ferromagnetic material; And a tunneling barrier layer disposed on the free layer. It includes, characterized in that having a structure in which the heavy metal layer, the free layer and the tunneling barrier layer is sequentially stacked.

In the free layer, generation and position of generation of scumions as phase objects are controlled.

In this case, the scumion preferably has an area of 1 nm ³ or less.

The skimion may be a Neil-type Skyrmion or a Bloch-type Skyrmion.

In particular, the spin synaptic device is an electrical operation of the magnetized state by the spin orbital torque coupling between the heavy metal material and the ferromagnetic material.

The heavy metal material is platinum (Pt), nickel (Ni), manganese (Mn), tin (Sn), zinc (Zn), barium (Ba), antimony (Sb), cadmium (Cd), bismuth (Bi), vanadium It may include one or more selected from (V) and selenium (Se), the heavy metal layer is preferably having a thickness of 0.1 ~ 3nm.

The ferromagnetic material may include at least one selected from Fe, Co, Ni, B, Si, Zr, Pt, Tb, Pd, Cu, W, and Ta, and the tunneling barrier layer may include MgO, Al ₂ O ₃ , It may include one or more selected from HfO ₂ , TiO ₂ , Y ₂ O ₃ and Yb ₂ O ₃ .

In addition, the spin synaptic device may further include a pinned layer stacked on the tunneling barrier layer.

The pinned layer is disposed on the tunneling barrier layer, the ferromagnetic layer made of a ferromagnetic material; A first oxygen reservoir layer disposed on the ferromagnetic layer; A first crystallization auxiliary layer disposed on the first oxygen reservoir layer; A second oxygen reservoir layer disposed on the first crystallization auxiliary layer; And a second crystallization auxiliary layer disposed on the second oxygen reservoir layer.

In this case, each of the first and second oxygen reservoir layers may include any one of Ta, Ru, and Ta-Ru alloys.

In addition, the skimion-based spin synapse device is a substrate disposed under the heavy metal layer; And a capping layer disposed on the second crystallization auxiliary layer.

According to another aspect of the present invention, there is provided a method of manufacturing a skimion-based spin synapse device, the method including: forming a heavy metal layer made of a heavy metal material on a substrate; Forming a free layer of ferromagnetic material on the heavy metal layer; And forming a tunneling barrier layer on the free layer; It includes, characterized in that having a structure in which the heavy metal layer, the free layer and the tunneling barrier layer is sequentially stacked.

In this case, the spin synaptic element is controlled to generate and generate the position of the phase object squameon in the free layer, the skimion has an area of 1nm ³ or less.

The skimion may be a Neil-type Skyrmion or a Bloch-type Skyrmion.

The spin snap element has an electrical operation in a magnetized state by coupling a spin orbital torque between the heavy metal layer and the free layer.

The method may further include forming a pinned layer on the tunneling barrier layer.

The scumion-based spin synaptic device and its manufacturing method according to the present invention can secure extremely low power, multi-valued, and linearity through the control of the property of the scumion, and thus, when applied to the nerve mimic technology, recognition, judgment, low power, etc. As far as possible, the paradigm of related technologies can be changed.

In addition, the spin synapse device and the method of manufacturing the same according to the present invention enable the implementation of new devices in the field of artificial intelligence hardware, and can be extended to the system implementation by integrating with the artificial intelligence algorithm and circuit technology in the future.

In addition, the spin synaptic device and the method of manufacturing the same according to the present invention can be implemented at a higher speed at an ultra-low power, since the recently developed deep neural algorithm network is not only difficult to process continuously and in real time, but also has a very high power consumption CMOS. It will be able to solve the problems in the field of artificial intelligence hardware.

1 is a schematic diagram showing a scumion-based spin synaptic device according to an embodiment of the present invention.
Figure 2 is a cross-sectional view showing in more detail the skumion-based spin synaptic device according to an embodiment of the present invention.
3 is an enlarged perspective view of the free layer of FIG. 2;
Figure 4 is a schematic diagram showing the form for each type of skimion.
5 is a schematic diagram for explaining the generation and movement path of the scumion according to the applied pulse.
6 is a schematic diagram for explaining the change in analog resistance according to the position of the number of skimions.
7 is a schematic diagram for explaining the spin hole effect and the lash bar effect when using the spin trajectory torque.
Fig. 8 is a schematic diagram for specifically describing the lash bar effect when using spin orbital torque.
9 is a schematic diagram for explaining the spin trajectory torque in more detail.
10 is a schematic diagram for explaining switching characteristics in spin synaptic element operation using spin orbital torque.
Fig. 11 is a schematic diagram for explaining a writing process in spin synaptic element operation using spin orbital torque.
12 is a graph of switching voltage versus writing and reading in spin synaptic device operation using spin orbital torque.
FIG. 13 is a process flowchart illustrating a method of manufacturing a scumion-based spin synaptic device according to an embodiment of the present invention. FIG.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the present embodiments to make the disclosure of the present invention complete, and common knowledge in the art to which the present invention pertains. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, a skimion-based spin synaptic device and a method of manufacturing the same according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram showing a scumion-based spin synaptic device according to an embodiment of the present invention.

Referring to FIG. 1, the skimion-based spin synaptic device 100 according to an embodiment of the present invention includes a heavy metal layer 110, a free layer 120, and a tunneling barrier layer 130.

The heavy metal layer 110 is made of a heavy metal material. At this time, the heavy metal material is platinum (Pt), nickel (Ni), manganese (Mn), tin (Sn), zinc (Zn), barium (Ba), antimony (Sb), cadmium (Cd), bismuth (Bi), At least one selected from vanadium (V) and selenium (Se) is included, and among these, platinum (Pt) is preferably used.

The heavy metal layer 110 preferably has a very thin thickness, specifically, it is preferable to have a thickness of 0.1 to 3 nm, which is required to form the heavy metal layer 110 in a considerably thin thickness range of 0.1 to 3 nm free layer ( This is because skirmion nucleation may occur at the interface with 120).

The free layer 120 is disposed on the heavy metal layer 110 and is made of a ferromagnetic material. The free layer 120 serves to store information.

In this case, a ferromagnetic material having vertical magnetic anisotropy is used as the material of the free layer 120. Specifically, the ferromagnetic material may include one or more selected from Fe, Co, Ni, B, Si, Zr, Pt, Tb, Pd, Cu, W, Ta, etc. Among them, using a CoFe-based alloy Preferably, the most preferred material may be presented CoFeB.

The tunneling barrier layer 130 is disposed on the free layer 120. An insulating material may be used as the material of the tunneling barrier layer 130. Specifically, at least one selected from MgO, Al ₂ O ₃ , HfO ₂ , TiO ₂ , Y ₂ O _3, and Yb ₂ O ₃ may be used as the material of the tunneling barrier layer 130, and MgO may be used. It is preferable to use.

The skimion-based spin synaptic device 100 according to the embodiment of the present invention has a structure in which the heavy metal layer 110, the free layer 120, and the tunneling barrier layer 130 are sequentially stacked.

As such, the scumion-based spin synaptic device 100 according to the embodiment of the present invention may have various magnetic systems in which Heisenberg interaction and DMI (Dzaloshinskii-Moriya) interaction occur simultaneously, that is, the heavy metal layer 110. In the structure in which the free layer 120 and the tunneling barrier layer 130 are sequentially stacked, a skirmion known as a topology object is formed.

In addition, the skimion-based spin synaptic device 100 according to the embodiment of the present invention has a great advantage of being moved while maintaining its shape very stably through the control of the skimion behavior using spin orbit torque (SOT). I can have it.

This will be described in more detail with reference to the accompanying drawings below.

Figure 2 is a cross-sectional view showing in more detail the scumion-based spin synaptic device according to an embodiment of the present invention.

Referring to FIG. 2, the scumion-based spin synaptic device 100 according to the embodiment of the present invention may further include a substrate 101, a pinned layer 140, and a capping layer 150.

The substrate 101 is disposed on the rear surface of the heavy metal layer 110 to support the heavy metal layer 110. As the substrate 101, various known materials may be used. For example, a silicon substrate may be used as the substrate 101. In addition, the substrate 101 may be implemented as an electrode, or may be omitted in some cases.

The pinned layer 140 is stacked on the tunneling barrier layer 130. The pinned layer 140 is set so that the magnetization direction is fixed so as not to be affected by external magnetization.

More specifically, the pinned layer 140 is disposed on the tunneling barrier layer 130, a ferromagnetic layer 141 made of a ferromagnetic material, a first oxygen reservoir layer 142 disposed on the ferromagnetic layer 141, and And a first crystallization auxiliary layer 143 disposed on the first oxygen reservoir layer 142.

In addition, the pinned layer 140 may include a second oxygen reservoir layer 144 disposed on the first crystallization auxiliary layer 143 and a second crystallization auxiliary layer 145 disposed on the second oxygen reservoir layer 144. It may further include.

At this time, the ferromagnetic layer 141 may be formed of a ferromagnetic material containing at least one selected from Fe, Co, Ni, B, Si, Zr, Pt, Tb, Pd, Cu, W, Ta, etc. Among these, CoFe It is preferable to use a base alloy, and CoFeB may be proposed as the most preferable material.

The first oxygen reservoir layer 142 stores oxygen released from the first crystallization auxiliary layer 143, and the second oxygen reservoir layer 144 stores oxygen released from the second crystallization auxiliary layer 145. It serves to store. To this end, each of the first and second oxygen reservoir layers 142 and 144 preferably include any one of Ta, Ru, and Ta-Ru alloys.

Each of the first and second crystallization auxiliary layers 143 and 145 may have the form of a multilayer thin film in which an oxide-based material layer and a non-magnetic material layer, each of which has a ferromagnetic material as a main element, are alternately stacked at least one or more times. In this case, Pd or Pt material may be used as the nonmagnetic material layer.

For example, each of the first and second crystallization auxiliary layers 143 and 145 may be a ((Co-O or Fe-O) / (Pd or Pt) _m multilayer thin film, where m is 2 to 10. .

The capping layer 150 is disposed on the second crystallization auxiliary layer 145. The capping layer 150 covers the upper portion of the second crystallization auxiliary layer 145 to prevent the pinned layer 140 from being oxidized. To this end, Ta may be used as the capping layer 150, but is not limited thereto.

Meanwhile, FIG. 3 is an enlarged perspective view of the free layer 120 of FIG. 2, and FIG. 4 is a schematic view showing types of skimions by type, which will be described with reference to FIG. 2.

First, as shown in FIGS. 2 and 3, the skimion-based spin synaptic device 100 according to the embodiment of the present invention may include a heavy metal layer 110, a free layer 120, and a tunneling barrier layer 130 in turn. By the stacked structure, the generation and the position of the cumulion 125 which is a phase object in the free layer 120 are controlled.

In this case, the scumion 125 may have various magnetic systems in which Heisenberg interaction and DMI (Dzaloshinskii-Moriya) interaction occur simultaneously, that is, the heavy metal layer 110, the free layer 120, and the tunneling barrier layer ( 130 is formed in a stacked structure in turn.

The scumion 125 has a very small area of 1 nm ³ or less, and can be operated with several times less energy than the conventional one, and thus is suitable as a basic unit of an information device of the future. In addition, the scumion 125 has a great advantage over the conventional magnetic domain wall-based spin synaptic element in that the phase is solitone, interacting with the surroundings, the very stable state can be moved at the same speed.

On the other hand, as shown in Figures 3 and 4, the skimion 125 refers to a special spin structure occurs when there is a large DMI (Dzaloshinskii-Moriya) interaction phenomenon.

At this time, the DMI is known to be determined according to the crystal structure or the interface state, and according to the shape of the DMI, the skimion 125 may be a Neil-type Skyrmion and a Bloch-type Skyrmion. ) Will have any one form.

That is, the Neil-type Skyrmion illustrated in FIG. 4A has an arrangement structure in which an arrow indicating a spin direction evenly extends out from the center of the sphere.

In addition, the Bloch-type Skyrmion illustrated in FIG. 4B has a spiral arrangement in which an arrow indicating the spin direction extends from the edge of the sphere to the center.

In this case, the scumion-based spin snap device according to the embodiment of the present invention is an electrical operation of the magnetized state by the spin orbital torque coupling between the heavy metal material and the ferromagnetic material.

5 is a schematic diagram for explaining generation and movement paths of skirmions according to an applied pulse, and FIG. 6 is a schematic diagram for explaining changes in analog resistance depending on the number positions of skirmions.

As shown in FIG. 5, a top view and a cross-sectional view showing the generation and movement hardness of the cumeonion are shown, respectively.

At this time, as shown in Figures 5 and 6, it can be seen that the generation and generation position of the skimion in accordance with the applied pulse. That is, it can be seen that the number of skimions according to the applied pulses in each domain is changed, and the weight of the spin synaptic element changes as the analog resistance changes depending on the number position of the skimions.

Accordingly, the resistance change may be induced by controlling the number of scumions in the device structure according to the repeated external pulse stimulus. Through the control of the properties of the Scumion it is possible to implement a spin synapse function by ensuring a linear multi-valued at an extremely low power.

In other words, in the existing magnetic domain wall-based spin synaptic devices, the generation of domain walls is not only difficult to specify the generation point because the demagnetization always occurs near the edge of the unstable device. Quite large, approximately 10 ⁶ A / cm 2.

In addition, in the existing magnetic domain wall-based spin synaptic device, the magnetic domain wall motion is always affected by demagnetization due to defects or interfacial impurities.

In contrast, in the skimion-based spin synapse device according to an embodiment of the present invention, the generation of the skimion is artificial because the device structure may appear only in a special form, that is, a structure in which a heavy metal layer, a free layer, and a tunneling barrier layer are sequentially stacked. The generation point can be specified and the generation current is considerably low, about 10 ⁴ A / cm 2 or less. In addition, Scumion is a type of soliton that is preserved in phase, and is not affected by peripheral defects or impurities, so that it can be operated at a very low power of about 10 ² A / cm 2 or less by enabling constant operation control during device operation. It becomes possible.

Accordingly, the skimion-based spin synaptic device according to the embodiment of the present invention may have a great advantage of being moved while maintaining its shape very stably through the control of the skimion behavior using the spin orbital torque (SOT).

In particular, it shows a very good form to solve the problem of linearity and symmetry of synapse, which is a common problem in many synapses related papers, which is due to the nature of scumions that are moved only by special symmetry. It is considered that it is not affected and reacts only by the operating current.

In particular, using the behavior control of the skimion it is possible to secure a step resistance change (multi-value) while having a linearity superior to the results of the existing magnetic domain wall movement control. In addition, by controlling the speed and the degree of movement of the cumeon through appropriate doping and morphology of the device, it is possible to ensure the linearity and multi-value of the spin synapse operating at a very low power.

On the other hand, Figure 7 is a schematic diagram for explaining the spin hole effect and the lash bar effect when using the spin orbital torque, Figure 7 (a) shows the spin hole effect, Figure 7 (b) shows the lash bar effect. will be.

As shown in FIGS. 7A and 7B, in the case of a spin synaptic device using spin orbital torque, any one of the spin hall effect and the rashba effect, or spin It causes a combination of the Hall effect and the lash bar effect.

Here, the spin hole effect means that the hole effect is caused by the magnetic field caused by the spin induced even when there is no external magnetic field. However, if a sufficiently strong magnetic field is caught in a direction perpendicular to the orientation of the spin of the surface, the spin hole effect disappears because the spin precession moves around the direction of the magnetic field. On the other hand, the Rashba effect is a phenomenon in which a magnetic field is generated when an electric field is applied when an electron moves, and mainly occurs in a place having high electron mobility.

In this case, as shown in FIG. 7A, electrons accelerated by an electric field in a general metal may experience spin-dependent scattering in a special situation.

On the other hand, in the pure mechanism without impurity atoms, an Aharonov-Bohm phase change occurs due to spin orbit coupling.

On the other hand, Figure 8 is a schematic diagram for explaining in detail the effect of the lash bar when using the spin orbital torque, will be described in connection with Figure 7 (b).

As shown in FIGS. 7B and 8, at the surface of the centrally symmetrical crystal, the change in potential creates an electric field in the z-axis direction. That is, α _R When = 0, the spin array of electrons is made in a direction perpendicular to the electric field, whereas when α _R ≠ 0, it can be seen that the spin of electrons does not form a vertical array with respect to the electric field.

At this time, the electric field generally induced at the interface of the metal is concentrated on the surface and the interface by the screening effect length.

Thus, the Rashva effect only affects ultrathin ferromagnetic layers.

9 is a schematic diagram for explaining the spin trajectory torque in more detail, and FIG. 10 is a schematic diagram for explaining switching characteristics in the spin synaptic element operation using the spin trajectory torque.

As shown in FIGS. 9 and 10, in the case of the spin synaptic element using the spin orbital torque, since the direction of the injected spin is an angular direction of 90 degrees of the existing magnetization direction, switching is performed due to strong torque in exactly one direction. It can be seen that the time is quite short, approximately 100ps.

FIG. 11 is a schematic diagram illustrating a writing process in a spin synaptic device operation using spin orbital torque, and FIG. 12 is a graph of switching voltages according to writing and reading in spin synaptic device operation using spin orbital torque.

As shown in FIGS. 11 and 12, in the case of the spin synaptic device using the spin orbital torque, since the current passes directly through the heavy metal layer during writing, the tunneling barrier layer MgO does not pass through the tunneling barrier layer. The problem of breakdown of floors can be solved.

Meanwhile, FIG. 13 is a flowchart illustrating a method of manufacturing a scumion-based spin synaptic device according to an embodiment of the present invention.

As shown in FIG. 13, the method of manufacturing a skimion-based spin synapse device according to an embodiment of the present invention includes forming a heavy metal layer made of a heavy metal material on a substrate (S110), and a ferromagnetic material on the heavy metal layer. A free layer forming step (S120) of forming a free layer consisting of, a tunneling barrier layer forming step (S130) of forming a tunneling barrier layer on the free layer. In this case, the heavy metal layer, the free layer, and the tunneling barrier layer are sequentially stacked.

In addition, the method may further include a pinned layer forming step S140 performed after the tunneling barrier layer forming step S130.

Although not shown in the drawings, a capping layer may be further formed after the pinned layer forming step (S140).

Although the above has been described with reference to the embodiments of the present invention, various changes and modifications can be made at the level of those skilled in the art. Such changes and modifications can be said to belong to the present invention without departing from the scope of the technical idea provided by the present invention. Therefore, the scope of the present invention will be determined by the claims described below.

100: spin snap element 101: substrate
110: heavy metal layer 120: free layer
125: skimion 130: tunneling barrier layer
140: fixed layer 141: ferromagnetic layer
142: first oxygen reservoir layer 143: first antiferromagnetic layer
144: second oxygen reservoir layer 145: second antiferromagnetic layer
150: capping layer

Claims (18)

A heavy metal layer made of a heavy metal material;
A free layer disposed on the heavy metal layer and made of a ferromagnetic material; And
A tunneling barrier layer disposed on the free layer; Including;
A scumion-based spin synaptic device having a structure in which the heavy metal layer, the free layer, and the tunneling barrier layer are sequentially stacked.
The method of claim 1,
A spinumion-based spin synaptic device in which the generation and position of a phase object, the squamion, is controlled in the free layer.
The method of claim 2,
The skimion is
Scumion-based spin synaptic devices with an area of less than 1 nm ³ .
The method of claim 2,
The skimion is
Skirmion-based spin synaptic devices that are Neil-type Skyrmion or Bloch-type Skyrmion.
The method of claim 1,
A spinumion-based spin synaptic device in which the magnetization state is electrically operated by the spin orbital torque coupling between the heavy metal layer and the free layer.
The method of claim 1,
The heavy metal material is
Platinum (Pt), Nickel (Ni), Manganese (Mn), Tin (Sn), Zinc (Zn), Barium (Ba), Antimony (Sb), Cadmium (Cd), Bismuth (Bi), Vanadium (V) and Scumion-based spin synaptic device comprising at least one selected from selenium (Se).
The method of claim 1,
The heavy metal layer is
Scumion-based spin synaptic devices with a thickness of 0.1-3 nm.
The method of claim 1,
The ferromagnetic material is
Scumion-based spin synaptic device comprising at least one selected from Fe, Co, Ni, B, Si, Zr, Pt, Tb, Pd, Cu, W, and Ta.
The method of claim 1,
The tunneling barrier layer is
A scumion-based spin synaptic device comprising at least one selected from MgO, Al ₂ O ₃ , HfO ₂ , TiO ₂ , Y ₂ O _3, and Yb ₂ O ₃ .
The method of claim 1,
A spinumion-based spin synaptic device further comprising a pinned layer stacked on the tunneling barrier layer.
The method of claim 10,
The pinned layer is
A ferromagnetic layer disposed on the tunneling barrier layer and formed of a ferromagnetic material;
A first oxygen reservoir layer disposed on the ferromagnetic layer;
A first crystallization auxiliary layer disposed on the first oxygen reservoir layer;
A second oxygen reservoir layer disposed on the first crystallization auxiliary layer; And
A second crystallization auxiliary layer disposed on the second oxygen reservoir layer;
Scumion-based spin synaptic device comprising a.
The method of claim 11,
Each of the first and second oxygen reservoir layers
Scumion-based spin synaptic devices comprising any of Ta, Ru, and Ta-Ru alloys.
The method of claim 11,
The scumion-based spin synapse device
A substrate disposed under the heavy metal layer; And
A capping layer disposed on the second crystallization auxiliary layer;
A skimion-based spin synaptic device further comprising.
Forming a heavy metal layer made of a heavy metal material on the substrate;
Forming a free layer of ferromagnetic material on the heavy metal layer; And
Forming a tunneling barrier layer on the free layer; Including;
Method of manufacturing a scumion-based spin synaptic device having a structure in which the heavy metal layer, the free layer and the tunneling barrier layer are sequentially stacked.
The method of claim 14,
The generation and position of the generation of the phase object skumion in the free layer is controlled, the skumion-based spin synapse device having an area of 1nm ³ or less.
The method of claim 15,
The skimion is
Method of manufacturing a skimmerion-based spin synaptic device, which is a Neil-type Skyrmion or a Bloch-type Skyrmion.
The method of claim 14,
A method of manufacturing a scumion-based spin synaptic device in which an electrical operation of a magnetized state is performed by spin orbital torque coupling between the heavy metal layer and the free layer.
The method of claim 14,
And forming a pinned layer on the tunneling barrier layer.

Images