KR102606509B1 - Variable low resistance area based electronic device and controlling thereof - Google Patents

Abstract

One embodiment of the present invention includes an active layer containing a spontaneously polarizable material, an applied electrode disposed adjacent to the active layer, a polarization region formed in the active layer by applying an electric field to the active layer through the applied electrode, and a boundary of the polarization region. At least one variable low-resistance region including a region having lower electrical resistance than another adjacent region, a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region, and a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region. Disclosed is an electronic device based on a variable low-resistance region including a second electrode connected to and having different electrical characteristics from the first electrode.

Description

{Variable low resistance area based electronic device and controlling the same}

The present invention relates to an electronic device using a variable low-resistance region and a method of controlling the same.

As technology advances and people's interest in convenience in life increases, attempts to develop various electronic products are becoming more active.

Additionally, these electronic products are becoming increasingly smaller and more integrated, and the locations in which they are used are increasing widely.

These electronic products include various electrical devices, such as CPUs, memory, and various other electrical devices. These devices may include various types of electrical circuits.

For example, electrical devices are used in products in a variety of fields, including not only computers and smartphones, but also home sensor devices for IoT and bioelectronic devices for ergonomics.

Meanwhile, with the recent pace of technological development and rapid improvement in users' living standards, the use and application areas of these electric devices are rapidly increasing, and the demand for them is also increasing accordingly.

According to this trend, there are limitations in implementing and controlling electronic circuits that can be easily and quickly applied to various commonly used electrical devices.

Meanwhile, memory elements, especially non-volatile memory elements, are widely used as information storage and/or processing devices in various electronic devices such as computers, cameras, and communication devices.

These memory devices are being developed a lot, especially in terms of lifespan and speed. Most of the challenges are securing memory lifespan and speed, but there are limits to implementing improved memory devices.

The present invention can provide a variable low-resistance region-based electronic device and a control method thereof that can be easily applied to various purposes.

One embodiment of the present invention includes an active layer containing a spontaneously polarizable material, an applied electrode disposed adjacent to the active layer, a polarization region formed in the active layer by applying an electric field to the active layer through the applied electrode, and a boundary of the polarization region. At least one variable low-resistance region including a region having lower electrical resistance than another adjacent region, a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region, and a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region. Disclosed is an electronic device based on a variable low-resistance region including a second electrode connected to and having different electrical characteristics from the first electrode.

In this embodiment, the first electrode and the second electrode may include materials with different electrical properties.

In this embodiment, the work function of the first electrode may be smaller than the work function of the second electrode.

In this embodiment, the first electrode and the second electrode include a metal material, and the work function of the metal material contained in the first electrode is smaller than the work function of the metal material contained in the second electrode. can do.

Another embodiment of the present invention includes an active layer including a spontaneously polarizable material, an applied electrode disposed adjacent to the active layer, and a polarization region formed in the active layer by applying an electric field to the active layer through the applied electrode; At least one variable low-resistance region including a region with lower electrical resistance than other adjacent regions corresponding to the boundary of the polarization region, a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region, and spaced apart from the applying electrode. For an electronic device based on a variable low-resistance region that is connected to the variable low-resistance region and includes a second electrode having different electrical characteristics from the first electrode, an electric field is applied to the active layer through the applying electrode to polarize the active layer. forming a region and forming a variable low-resistance region including a region with lower electrical resistance than other adjacent regions corresponding to the boundary of the polarization region, thereby forming the first electrode and the first electrode through the variable low-resistance region. Disclosed is a method for controlling an electronic device based on a variable low-resistance region, including forming a current flow between two electrodes.

In this embodiment, the step of controlling the application electrode and measuring the current between the first electrode and the second electrode as the variable low-resistance region is formed may be included.

In this embodiment, the method may include controlling the polarization region by controlling the electric field through the applied electrode, and generating or disappearing the variable low-resistance region according to control of the polarization region.

Other aspects, features and advantages in addition to those described above will become apparent from the following drawings, claims and detailed description of the invention.

The electronic device and its control method using a variable low-resistance region according to the present invention can be easily applied to various purposes.

1 is a schematic plan view showing an electronic circuit according to an embodiment of the present invention.
Figure 2 is a cross-sectional view taken along line II-II of Figure 1.
Figure 3 is an enlarged view of K in Figure 2.
FIGS. 4A to 4C are diagrams for explaining a control method related to the electronic circuit of FIG. 1. Figure 5 is a schematic plan view showing an electronic circuit according to another embodiment of the present invention.
Figure 6 is a cross-sectional view taken along line VI-VI of Figure 5.
FIGS. 7A to 7D are diagrams for explaining a current path range control method related to the electronic circuit of FIG. 5.
Figure 8 is a schematic plan view showing an electronic device according to an embodiment of the present invention.
Figure 9 is a cross-sectional view taken along line II-II of Figure 8.
FIGS. 10 to 14 are diagrams for explaining the operation of the electronic device of FIG. 8.
Figure 15 is a schematic cross-sectional view showing an electronic device according to another embodiment of the present invention.
FIG. 16 is a diagram schematically showing the energy level of each region of the electronic device of FIG. 15.
Figure 17 is a schematic cross-sectional view showing an electronic device according to another embodiment of the present invention.
Figure 18 is a schematic plan view showing an electronic device according to another embodiment of the present invention.
FIG. 19 is a cross-sectional view taken along line VI-VI of FIG. 18.
Figure 20 is a graph showing the voltage and current relationship in the variable low-resistance region.
Figure 21 is a cross-sectional view of a variable low-resistance based electronic device according to another embodiment of the present invention.
Figure 22 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.
Figure 23 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.
Figure 24 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.
Figure 25 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.
26 and 27 are cross-sectional views schematically showing an example of an electronic device according to another embodiment of the present invention.
FIG. 28 is a cross-sectional view schematically showing another example of the electronic device of FIG. 26.
FIG. 29 is a cross-sectional view schematically showing another example of the electronic device of FIG. 26.
FIG. 30 is a cross-sectional view schematically showing another example of the electronic device of FIG. 26.
FIG. 31 is a cross-sectional view schematically showing an example of the II' cross-section of the electronic device of FIG. 26.
FIG. 32 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.
FIG. 33 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.
FIG. 34 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.
FIG. 35 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.
FIG. 36 is a cross-sectional view schematically showing another example of a cross-section taken along line II' of the electronic device of FIG. 26.

Hereinafter, the configuration and operation of the present invention will be described in detail with reference to embodiments of the present invention shown in the attached drawings.

Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various forms.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the drawings, identical or corresponding components will be assigned the same reference numerals and redundant description thereof will be omitted. .

In the following embodiments, terms such as first and second are used not in a limiting sense but for the purpose of distinguishing one component from another component.

In the following examples, singular terms include plural terms unless the context clearly dictates otherwise.

In the following embodiments, terms such as include or have mean that the features or components described in the specification exist, and do not exclude in advance the possibility of adding one or more other features or components.

In the drawings, the sizes of components may be exaggerated or reduced for convenience of explanation. For example, the size and thickness of each component shown in the drawings are shown arbitrarily for convenience of explanation, so the present invention is not necessarily limited to what is shown.

In the following embodiments, the x-axis, y-axis, and z-axis are not limited to the three axes in the Cartesian coordinate system, but can be interpreted in a broad sense including these. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may also refer to different directions that are not orthogonal to each other.

In cases where an embodiment can be implemented differently, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially at the same time, or may be performed in an order opposite to that in which they are described.

FIG. 1 is a schematic plan view showing an electronic circuit according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIG. 3 is an enlarged view of K in FIG. 2.

Referring to FIGS. 1 and 2 , the electronic circuit 10 of this embodiment may include an active layer 11, an applied electrode 12, and a variable low-resistance region (VL).

The active layer 11 may include a spontaneously polarizable material. For example, the active layer 11 includes an insulating material and may include a ferroelectric material. That is, the active layer 11 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional example, the active layer 11 may include a perovskite-based material, for example, BaTiO _3, SrTiO _3, BiFe3, PbTiO3, PbZrO3, and SrBi2Ta2O9.

Also, as another example, the active layer 11 has an ABX3 structure, where A may include an alkyl group of CnH2n+1 and one or more materials selected from inorganics such as Cs and Ru capable of forming a perovskite solar cell structure, and B may include one or more materials selected from the group consisting of Pb, Sn, Ti, Nb, Zr, and Ce, and X may include a halogen material. As a specific example, the active layer 11 is CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbI _x Cl _3-x , MAPbI _3, CH ₃ NH ₃ PbI _x Br _3-x , CH ₃ NH ₃ PbClxBr _3-x , HC (NH ₂ ) ₂ PbI ₃ , HC(NH ₂ ) ₂ PbI _x Cl _3-x , HC(NH ₂ ) ₂ PbI _x Br _3-x , HC(NH ₂ ) ₂ PbCl _x Br _3-x , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI ₃ , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI _x Cl _3-x , (CH ₃ NH ₃ )(HC( NH ₂ ) ₂ ) _1-y PbI _x Br _3-x , or (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbCl _x Br _3-x (0≤x, y≤1) can do.

Since the active layer 11 can be formed using various other ferroelectric materials, descriptions of all examples thereof will be omitted. Additionally, when forming the active layer 11, the ferroelectric material may be doped with various other materials to include additional functions or improve electrical properties.

The active layer 11 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 11 can maintain its polarization state even when the applied electric field is removed.

The application electrode 12 may be formed to apply an electric field to the active layer 11, and for example, may apply a voltage to the active layer 11.

As an optional embodiment, the applying electrode 12 may be formed to contact the top surface of the active layer 11.

Additionally, the application electrode 12 can be formed to apply voltages of various sizes to the active layer 11 and to control the time of voltage application.

As an alternative embodiment, the input electrode 12 may be a gate electrode.

For example, the application electrode 12 may be electrically connected to a power source (not shown) or a power control unit.

The applying electrode 12 may include various materials and may include materials with high electrical conductivity. For example, the application electrode 12 can be formed using various metals.

For example, the application electrode 12 can be formed to contain aluminum, chromium, titanium, tantalum, molybdenum, tungsten, neodymium, scandium or copper. Alternatively, it can be formed using alloys of these materials or nitrides of these materials.

Additionally, as an optional embodiment, the applying electrode 12 may include a laminate structure.

Although not shown, as an optional embodiment, one or more insulating layers may be further disposed between the applying electrode 12 and the active layer 11.

The variable low-resistance region (VL) is a region formed in the active layer 11 through which current can flow, and can also be formed as a linear current path around the application electrode 12, as shown in FIG. 1. there is.

Specifically, the variable low-resistance region (VL) is a region of the active layer 11 with lower electrical resistance than other regions adjacent to the variable low-resistance region (VL).

In addition, after forming the variable low-resistance region (VL) through the application electrode 12, even if the electric field through the application electrode 12 is removed, for example, even if the voltage is removed, the polarization state of the active layer 11 remains. Since this is maintained, the variable low-resistance region (VL) is maintained and a current path can be maintained.

Through this, various electronic circuits can be constructed.

The variable low-resistance region VL has a height HVL, and this height HVL may correspond to the overall thickness of the active layer 11.

The height (HVL) of this variable low-resistance region (VL) may be proportional to the intensity of the electric field, for example, the magnitude of the voltage, when the electric field is applied through the application electrode 12. At least the size of this electric field may be larger than the inherent coercive electric field of the active layer 11.

The variable low-resistance region (VL) is a region formed when voltage is applied to the active layer 11 through the applied electrode 12, and can vary, for example, create, disappear, or move through control of the applied electrode 12. .

The active layer 11 may include a first polarization region 11F having a first polarization direction, and a variable low-resistance region VL may be formed at the boundary of the first polarization region 11F.

In addition, it may include a second polarization region 11R having a second polarization direction adjacent to the first polarization region 11F, and the variable low-resistance region VL is located at the boundary of the second polarization region 11R. can be formed. The second direction may be at least a different direction from the first direction, for example, a direction opposite to the first direction.

For example, the variable low-resistance region VL may be formed between the first polarization region 11F and the second polarization region 11R. Through this, a first polarization region 11F having a polarization direction in a first direction (for example, a direction from bottom to top based on FIG. 2) centered on the variable low-resistance region VL and a polarization direction opposite to the first direction. The second polarization region 11R having a polarization direction (for example, a direction from top to bottom with respect to FIG. 2) may be arranged to be distinct.

The variable low-resistance region (VL) may have a width (WVL) in one direction, which may be proportional to the moving distance of the variable low-resistance region (VL).

Additionally, this width (WVL) may be the width of a region on a plane defined as the variable low-resistance region (VL), which can be said to correspond to the width of the first polarization region (11F).

Additionally, the variable low-resistance region VL may be formed to correspond to the entire side of the boundary line of the first polarization region 11F and may have a thickness TVL1 in a direction away from the side of the first polarization region 11F. there is.

As an alternative example, this thickness TVL1 may be between 0.1 and 0.3 nanometers.

FIGS. 4A to 4C are diagrams for explaining a current path range control method for the electronic circuit of FIG. 1 .

Referring to FIG. 4A, the active layer 11 may include a second polarization region 11R having a second polarization direction. As an optional embodiment, the polarization state of the active layer 11 as shown in FIG. 4A may be formed by applying an initializing electric field through the application electrode 12.

Then, referring to FIG. 4B, a first polarization region 11F is formed in the active layer 11. As a specific example, a first polarization region 11F may be formed in an area overlapping with the application electrode 12 to correspond to the width of the application electrode 12.

It is larger than the coercive electric field of the active layer 11 through the applied electrode 12, and is large enough to enable the height (HVL) of the first polarization region 11F to be formed to at least correspond to the entire thickness of the active layer 11. An electric field may be applied to the active layer 11.

By applying an electric field through the application electrode 12, the polarization direction of one region of the second polarization region 11R of the active layer 11 can be changed to change into the first polarization region 11F.

As an alternative embodiment, the growth rate of the first polarization region 11F in the height (HVL) direction may be very fast, for example, at a rate of 1 km/sec.

Then, if the electric field through the applied electrode 12 is continuously maintained, that is, over time, the first polarization region 11F moves in the horizontal direction H, that is, in the direction perpendicular to the height HVL, and increases in size. You can. That is, the area of the second polarization region 11R can be gradually converted into the first polarization region 11F.

As an alternative embodiment, the growth rate of the first polarization region 11F in the horizontal direction (H) may be very fast, for example, at a rate of 1 m/sec.

Through this, the size of the variable low-resistance region (VL) can be controlled. This size is, for example, the width of the variable low-resistance region (VL) and corresponds to the growth distance of the first polarization region (11F), so the growth speed and electric field It may be proportional to the holding time. For example, the growth distance may be proportional to the product of the growth speed and the electric field maintenance time.

Additionally, the growth speed of the first polarization region 11F may be proportional to the sum of the growth speed in the height (HVL) direction and the growth speed in the horizontal direction (H).

Therefore, the size of the variable low-resistance region (VL) can be adjusted as desired by controlling the electric field maintenance time.

Specifically, as shown in FIG. 4C, the first polarization region 11F spreads out and becomes large, and accordingly, the variable low-resistance region VL can also move in a direction away from the application electrode 12.

In this embodiment, an electric field is applied to the active layer through an applied electrode to form a first polarization region having a first polarization direction different from the second polarization direction in the active layer, and a first polarization region is formed at the boundary between the first polarization region and the second polarization region. A corresponding variable low-resistance region can be formed. This variable low-resistance area is a low-resistance area and can serve as a path for current, making it possible to easily form an electronic circuit.

In addition, in this embodiment, the height of the variable low-resistance region can be determined by controlling the size of the voltage through the applied electrode, for example, and specifically controlled to have a height corresponding to the entire thickness of the active layer. can do.

Additionally, the size, for example, width, of the variable low-resistance region can be determined by controlling the time for maintaining the electric field through the applied electrode. By controlling the size of this variable low-resistance area, the size of the path of current flow can be easily controlled.

In addition, even if the electric field through the applied electrode is removed, the polarization state of the polarization region is maintained, so the path of the current can be easily maintained. When the polarization region is expanded by continuously maintaining the electric field through the applied electrode, the fluctuation that has already been formed is reduced. In the resistance area, the resistance may be lowered so that no current flows.

Through this, the extinction of the current path can be controlled, and as a result, the flow of current can be easily controlled.

The electronic circuit of this embodiment can be controlled and used for various purposes, for example, one or more electrodes can be connected to contact a variable low-resistance region.

Figure 5 is a schematic plan view showing an electronic circuit according to another embodiment of the present invention.

Figure 6 is a cross-sectional view taken along line VI-VI of Figure 5.

Referring to FIGS. 5 and 6 , the electronic circuit 20 of this embodiment may include an active layer 21, an applied electrode 22, and variable low-resistance regions VL1, VL2, and VL3.

The active layer 21 may include a spontaneously polarizable material. For example, the active layer 21 includes an insulating material and may include a ferroelectric material. That is, the active layer 21 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional embodiment, the active layer 21 may include a perovskite-based material, and the detailed description is the same as the above-described embodiment and is therefore omitted.

The application electrode 22 may be formed to apply an electric field to the active layer 21, and for example, may apply a voltage to the active layer 21. Since the specific details are the same as the above-described embodiment, they are omitted.

The variable low-resistance regions (VL1, VL2, and VL3) may include a first variable low-resistance region (VL1), a second variable low-resistance region (VL2), and a third variable low-resistance region (VL3).

The first variable low-resistance area (VL1) may have a larger width than the second variable low-resistance area (VL2), and the second variable low-resistance area (VL2) may have a larger width than the third variable low-resistance area (VL3). there is. For example, the area surrounded by the first variable low-resistance area (VL1) has a larger width than the area surrounded by the second variable low-resistance area (VL2), and the area surrounded by the second variable low-resistance area (VL2) has a wider width than the area surrounded by the second variable low-resistance area (VL2). It can have a larger width than the area surrounded by the low-resistance area (VL3).

As an optional embodiment, the first variable low-resistance region (VL1) is disposed outside the second variable low-resistance region (VL2), and the second variable low-resistance region (VL2) is disposed outside the third variable low-resistance region (VL3). can be placed in

The first variable low-resistance region (VL1), the second variable low-resistance region (VL2), and the third variable low-resistance region (VL3) are regions formed in the active layer 21 and are regions through which current can flow, and the current has a linear shape. It can be formed as a path of .

Specifically, the first variable low-resistance region (VL1), the second variable low-resistance region (VL2), and the third variable low-resistance region (VL3) are the first variable low-resistance region (VL1) and the third variable low-resistance region (VL1) among the regions of the active layer 21. This is an area with lower electrical resistance than other areas adjacent to the 2 variable low-resistance area (VL2) and the third variable low-resistance area (VL3).

In addition, after forming the first variable low-resistance region (VL1), the second variable low-resistance region (VL2), and the third variable low-resistance region (VL3) through the applied electrode 22, Even if the electric field is removed, for example, the voltage is removed, the polarization state of the active layer 21 is maintained, so that the first variable low-resistance region (VL1), the second variable low-resistance region (VL2), and the third variable low-resistance region (VL3) is maintained and can maintain the state of forming a current path.

Through this, various electronic circuits can be constructed. For example, it may form at least a portion of a memory device capable of storing one or more data.

The variable low-resistance regions VL1, VL2, and VL3 have a height HVL, and this height HVL may correspond to the overall thickness of the active layer 21.

The active layer 21 may include first polarization regions 21F1 and 21F3 having a first polarization direction, and the variable low-resistance regions VL1, VL2, and VL3 are boundaries of the first polarization regions 21F1 and 21F3. can be formed in

In addition, it may include second polarization regions 21R1 and 21R2 having a second polarization direction adjacent to the first polarization regions 21F1 and 21F3, and the variable low-resistance region VL is formed in the second polarization region 21R1. , 21R2) can be formed at the boundary. The second direction may be at least a different direction from the first direction, for example, a direction opposite to the first direction.

For example, the first variable low-resistance region VL1 may be formed between the first polarization region 21F1 and the second polarization region 21R1.

Additionally, the second variable low-resistance region VL2 may be formed between the first polarization region 21F1 and the second polarization region 21R2.

Additionally, the third variable low-resistance region VL3 may be formed between the first polarization region 21F3 and the second polarization region 21R2.

FIGS. 7A to 7D are diagrams for explaining a current path range control method related to the electronic circuit of FIG. 5.

Referring to FIG. 7A, the active layer 21 may include a second polarization region 21R having a second polarization direction. As an optional embodiment, the polarization state of the active layer 21 as shown in FIG. 7A may be formed by applying an initializing electric field through the application electrode 22.

Then, referring to FIG. 7B, a first polarization region 21F is formed in the active layer 21. As a specific example, the first polarization region 21F may first be formed in an area overlapping the application electrode 22 to correspond to the width of the application electrode 22, and then grow in the horizontal direction to form a state as shown in FIG. 7B. Additionally, the first polarization region 21R of FIG. 7A may be reduced and changed into a first polarization region 21R1 of the same shape as that of FIG. 7B.

A first variable low resistance region VL1 may be formed between the first polarization region 21F and the second polarization region 21R1.

Then, referring to FIG. 7C, an electric field in a direction opposite to that of FIG. 7B is applied to convert the polarization direction of a portion of the first polarization region 21F into a second polarization region 21R2 having a polarization direction in the second direction. You can. For example, a second polarization region 21R2 may be formed having a polarization direction in a second direction opposite to the first polarization direction of the first polarization region 21F.

In addition, through this, the first polarization region 21F of FIG. 7B can be reduced in size and changed into the first polarization region 21F1 of the form shown in FIG. 7C.

A second variable low-resistance region VL2 may be formed between the second polarization region 21R2 and the first polarization region 21F1.

Since this polarization state is maintained, the first variable low-resistance region VL1 can be maintained as is.

Then, referring to FIG. 7D, an electric field in a direction opposite to that of FIG. 7C is applied to convert the polarization direction of a portion of the second polarization region 21R2 into a first polarization region 21F3 having a polarization direction in the first direction. can do. For example, a first polarization region 21F3 may be formed having a first polarization direction opposite to the second polarization direction of the second polarization region 21R2.

In addition, through this, the second polarization region 21R2 of FIG. 7C can be reduced in size and changed into the second polarization region 21R2 of the form shown in FIG. 7D.

A third variable low-resistance region VL3 may be formed between the second polarization region 21R2 and the first polarization region 21F3.

Since this polarization state is maintained, the first variable low-resistance region VL1 and the second variable low-resistance region VL2 are maintained, and a third variable low-resistance region VL3 can be added.

In this embodiment, an electric field is applied to the active layer through an applied electrode to form a first polarization region having a first polarization direction different from the second polarization direction in the active layer, and a first polarization region is formed at the boundary between the first polarization region and the second polarization region. A corresponding variable low-resistance region can be formed. This variable low-resistance area is a low-resistance area and can serve as a path for current, making it possible to easily form an electronic circuit.

Additionally, this embodiment can control the size of the electric field through the applied electrode and the direction of the electric field, thereby forming a plurality of first polarization regions or a plurality of second polarization regions with respect to the active layer.

A plurality of variable low-resistance regions may be formed on the boundary line between the plurality of first polarization regions or the plurality of second polarization regions. Since each of these plurality of variable low-resistance regions can form a path of current, electronic circuits of various shapes and purposes can be easily created and controlled.

For example, by selectively applying a plurality of variable low-resistance regions centered on the applied electrode, various current paths can be formed, and a memory that stores various data according to these current paths can be implemented.

FIG. 8 is a schematic plan view showing an electronic circuit according to an embodiment of the present invention, and FIG. 9 is a cross-sectional view taken along line II-II of FIG. 8.

8 and 9, the electronic device 100 of this embodiment may include an active layer 110, an applied electrode 120, a variable low-resistance region (VL), and one or more connection electrode portions 131 and 132. there is.

Active layer 110 may include a spontaneously polarizable material. For example, active layer 110 may include an insulating material and may include a ferroelectric material. That is, the active layer 110 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional embodiment, the active layer 110 may include a perovskite-based material, for example, BaTiO _3, SrTiO _3, BiFe3, PbTiO3, PbZrO3, and SrBi2Ta2O9.

Also, as another example, the active layer 110 has an ABX3 structure, where A may include an alkyl group of CnH2n+1 and one or more materials selected from inorganics such as Cs and Ru capable of forming a perovskite solar cell structure, and B may include one or more materials selected from the group consisting of Pb, Sn, Ti, Nb, Zr, and Ce, and X may include a halogen material. As a specific example, the active layer 110 is CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbI _x Cl _3-x , MAPbI _3, CH ₃ NH ₃ PbI _x Br _3-x , CH ₃ NH ₃ PbClxBr _3-x , HC (NH ₂ ) ₂ PbI ₃ , HC(NH ₂ ) ₂ PbI _x Cl _3-x , HC(NH ₂ ) ₂ PbI _x Br _3-x , HC(NH ₂ ) ₂ PbCl _x Br _3-x , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI ₃ , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI _x Cl _3-x , (CH ₃ NH ₃ )(HC( NH ₂ ) ₂ ) _1-y PbI _x Br _3-x , or (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbCl _x Br _3-x (0≤x, y≤1) can do.

Since the active layer 110 can be formed using various other ferroelectric materials, descriptions of all examples thereof will be omitted. Additionally, when forming the active layer 110, the ferroelectric material may be doped with various other materials to include additional functions or improve electrical properties.

The active layer 110 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 110 can maintain its polarization state even when the applied electric field is removed.

The application electrode 120 may be formed to apply an electric field to the active layer 110, and for example, may apply a voltage to the active layer 110.

As an optional embodiment, the applying electrode 120 may be formed to contact the top surface of the active layer 110.

Additionally, the application electrode 120 can be formed to apply voltages of various sizes to the active layer 110 and to control the time of voltage application.

As an alternative embodiment, the input electrode 120 may be a gate electrode.

For example, the application electrode 120 may be electrically connected to a power source (not shown) or a power control unit.

The applying electrode 120 may include various materials and may include materials with high electrical conductivity. For example, the application electrode 120 can be formed using various metals.

For example, the application electrode 120 may be formed to contain aluminum, chromium, titanium, tantalum, molybdenum, tungsten, neodymium, scandium, or copper. Alternatively, it can be formed using alloys of these materials or nitrides of these materials.

Additionally, as an optional embodiment, the applying electrode 120 may include a laminate structure.

The connection electrode parts 131 and 132 may include one or more electrode members, for example, a first connection electrode member 131 and a second connection electrode member 132.

The connection electrode portions 131 and 132 may be formed on the active layer 110, for example, may be formed on the upper surface of the active layer 110 to be spaced apart from the application electrode 120, and as an optional embodiment, the active layer 110 ) can be formed to contact.

The first connection electrode member 131 and the second connection electrode member 132 can be formed using various conductive materials. For example, the first connection electrode member 131 and the second connection electrode member 132 may be formed to contain aluminum, chromium, copper, tantalum, titanium, molybdenum, or tungsten.

As an optional embodiment, the first connection electrode member 131 and the second connection electrode member 132 may include a structure in which a plurality of conductive layers are stacked.

As an optional embodiment, the first connection electrode member 131 and the second connection electrode member 132 may be formed using a conductive metal oxide, for example, indium oxide (e.g., In ₂ O ₃ ) or tin oxide. (e.g., SnO ₂ ), zinc oxide (e.g., ZnO), indium tin oxide alloy (e.g., In ₂ O ₃ —SnO ₂ ), or indium zinc oxide alloy (e.g., In ₂ O ₃ —ZnO). can be formed.

As an optional embodiment, the connection electrode units 131 and 132 may be terminal members that include input and output of electrical signals.

Also, as a specific example, the first connection electrode member 131 and the second connection electrode member 132 of the connection electrode parts 131 and 132 may include a source electrode or a drain electrode.

FIGS. 10 to 14 are diagrams for explaining the operation of the electronic device of FIG. 8.

FIG. 10 is a diagram showing a state in which a first electric field is applied through the application electrode 120, FIG. 11 is a cross-sectional view taken along line VIII-VIII of FIG. 10, and FIG. 12 is an enlarged view of K in FIG. 11. am.

Referring to FIGS. 10 to 14 , when the first electric field is applied to the active layer 110 through the applied electrode 120, at least one region of the active layer 110 may include a polarization region 110F.

This polarization region 110F may be shaped to surround the application electrode 120 with the application electrode 120 as the center. The polarization region 110F may have a boundary line.

The first variable low-resistance region VL1 may be formed in an area corresponding to the side of this boundary line. Referring to FIG. 10 , it may be formed in a linear shape surrounding the application electrode 120 with the application electrode 120 as the center.

For example, the first variable low-resistance region VL1 may have a first width WVL1 in one direction so as to surround the application electrode 120 .

Additionally, the first variable low-resistance region VL1 may be formed to correspond to the entire side of the boundary line of the polarization region 110F and may have a thickness TVL1 in a direction away from the side of the polarization region 110F.

As an alternative example, this thickness TVL1 may be between 0.1 and 0.3 nanometers.

As an optional embodiment, a process of applying an initialization electric field to the active layer 110 may be performed before the first voltage is applied to the active layer 110 through the applying electrode 120.

The process of applying this initialization electric field to the active layer 110 may include converting the area of the active layer 110 into a polarization area in a direction different from the polarization area 110F, for example, into a polarization area in the opposite direction. .

Then, a polarization region 110F can be formed in one region by applying an electric field in the opposite direction.

The first variable low-resistance region VL1 formed at the boundary of the polarization region 110F of the active layer 110 may change into a region with lower resistance than other regions of the active layer 110. For example, the first variable low-resistance region VL1 may have a lower resistance than the polarization region 110F of the active layer 110 and the region of the active layer 110 surrounding the first variable low-resistance region VL1.

Through this, the first variable low-resistance region VL1 can form a current path.

As an optional embodiment, the first variable low-resistance region VL1 may correspond to one region of a plurality of domain walls provided in the active layer 110.

Additionally, this first variable low-resistance region VL1 can be maintained if the polarization state of the polarization region 110F of the active layer 110 is maintained. That is, even if the first voltage applied to the active layer 110 through the application electrode 120 is removed, the state of the variable low-resistance region VL1, that is, the low-resistance state, can be maintained.

As shown in FIGS. 10 and 11 , a current path may be formed through the first variable low-resistance region VL1. However, since the connection electrode units 131 and 132 do not correspond to the first variable low-resistance region VL1, current may not flow through the connection electrode units 131 and 132.

FIG. 13 is a diagram showing a state in which the first electric field is maintained for a certain period of time through the applied electrode 120, and FIG. 14 is a cross-sectional view taken along line XI-XI of FIG. 13.

Referring to FIGS. 13 and 14 , the maintenance time of the first electric field through the applied electrode 120 becomes longer, and the polarization region 110F of FIGS. 10 and 11 moves in the horizontal direction, thereby increasing the polarization region 110F. A second variable low-resistance region (VL2) larger than the first variable low-resistance region (VL1) may be formed.

For example, the voltage applied in FIGS. 10 and 11 can be continuously maintained for a certain period of time to form the structures shown in FIGS. 13 and 14.

The polarization region 110F may be shaped to surround the application electrode 120 with the application electrode 120 as the center. The polarization region 110F may have a boundary line. The second variable low-resistance region VL2 may be formed in an area corresponding to the side of the boundary line of the polarization region 110F. Referring to FIG. 13, it may be formed in a linear shape surrounding the application electrode 120 with the application electrode 120 as the center.

For example, the second variable low-resistance region VL2 may have a second width WVL2 in one direction to surround the application electrode 120, and the second width WVL2 is greater than the first width WVL1. You can.

In addition, the second variable low-resistance region VL2 may be formed to correspond to the entire side of the boundary line of the polarization region 110F and may have a thickness in a direction away from the side of the polarization region 110F, an optional embodiment. This thickness may be 0.1 to 0.3 nanometers.

The second variable low-resistance region VL2 formed at the boundary of the polarization region 110F of the active layer 110 may change into a region with lower resistance than other regions of the active layer 110. For example, the second variable low-resistance region VL2 may have a lower resistance than the polarization region 110F of the active layer 110 and the region of the active layer 110 surrounding the second variable low-resistance region VL2.

Through this, the second variable low-resistance region VL2 can form a current path.

As an optional embodiment, the second variable low-resistance region VL2 may correspond to one region of a plurality of domain walls provided in the active layer 110.

Additionally, this second variable low-resistance region VL2 can be maintained as long as the polarization state of the active layer 110 is maintained. That is, even if the second voltage applied to the active layer 110 through the application electrode 120 is removed, the state of the second variable low-resistance region VL2, that is, the low-resistance state, can be maintained.

Therefore, a current path can be formed through the second variable low-resistance region VL2.

In addition, as a specific example, the connection electrode parts 131 and 132 are formed to correspond to the second variable low-resistance region VL2, for example, the first connection electrode member 131 of the connection electrode parts 131 and 132 and The second connection electrode members 132 may be arranged to be in contact with the upper surface of the second variable low-resistance region VL2 while being spaced apart from each other.

Through this, current can flow through the first connection electrode member 131 and the second connection electrode member 132 of the connection electrode parts 131 and 132.

Additionally, various electrical signals can be generated. For example, when the electric field in the state of FIGS. 13 and 14 is applied more continuously, that is, when the application time increases, the second variable low-resistance region VL2 moves further to connect the first connection electrode member 131 and the first connection electrode member 131. 2 It is possible to leave the connection electrode member 132. Accordingly, current may not flow through the first connection electrode member 131 and the second connection electrode member 132.

Additionally, as an optional embodiment, an initialization process for the entire active layer 110 may be performed.

Then, when an electric field is applied to the active layer 110 through the application electrode 120 again, current flows through the first connection electrode member 131 and the second connection electrode member 132 of the connection electrode parts 131 and 132. You can.

The electronic circuit of this embodiment can apply voltages of various sizes to the active layer through an application electrode and control the application time.

Through this, a polarization region of a desired size can be formed in the active layer, and a variable low-resistance region can be formed at the boundary of this polarization region.

In order to correspond to this fluctuating low-resistance region, for example, when the connection electrode is formed to be in contact, current can flow through the connection electrode, and even when the voltage is removed, the active layer containing the ferroelectric material can maintain the polarization state. The fluctuating low-resistance region at the boundary can also be maintained, allowing current to continue to flow.

In addition, voltage can be applied to the active layer through an application electrode to change the variable low-resistance region into a polarization region, and through this, current does not flow in the connection electrode portion through which current flows.

The flow of current can be controlled by controlling the voltage of the applied electrode, and through control of the flow of current, electronic circuits can be used for various purposes.

As an alternative embodiment, electronic circuitry may be used as memory.

For example, it can be used as a memory by defining current flow as 1 and non-flow as 0. As a specific example, current can flow even when the voltage is removed, so it can also be used as a non-volatile memory.

Additionally, the electronic circuit can constitute a circuit part that generates and transmits various signals, and can also be used as a switching element.

In addition, since it can be applied with a simple structure to other parts that require control of electrical signals, it can be applied to various fields such as variable circuits, CPUs, and bio chips.

Figure 15 is a schematic cross-sectional view showing an electronic device according to another embodiment of the present invention.

The electronic device 200 of this embodiment may include an active layer 210, an applied electrode 220, a variable low-resistance region (VL2), and one or more connection electrode portions 231 and 232. The active layer 210 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 210 can maintain its polarization state even when the applied electric field is removed.

Active layer 210 may include a spontaneously polarizable material. For example, the active layer 210 may include an insulating material and may include a ferroelectric material. That is, the active layer 210 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional example, the active layer 210 may include a perovskite-based material, for example, BaTiO _3, SrTiO _3, BiFe3, PbTiO3, PbZrO3, and SrBi2Ta2O9.

Also, as another example, the active layer 210 has an ABX3 structure, where A may include an alkyl group of CnH2n+1 and one or more materials selected from inorganics such as Cs and Ru capable of forming a perovskite solar cell structure, and B may include one or more materials selected from the group consisting of Pb, Sn, Ti, Nb, Zr, and Ce, and X may include a halogen material. As a specific example, the active layer 11 is CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbI _x Cl _3-x , MAPbI _3, CH ₃ NH ₃ PbI _x Br _3-x , CH ₃ NH ₃ PbClxBr _3-x , HC (NH ₂ ) ₂ PbI ₃ , HC(NH ₂ ) ₂ PbI _x Cl _3-x , HC(NH ₂ ) ₂ PbI _x Br _3-x , HC(NH ₂ ) ₂ PbCl _x Br _3-x , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI ₃ , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI _x Cl _3-x , (CH ₃ NH ₃ )(HC( NH ₂ ) ₂ ) _1-y PbI _x Br _3-x , or (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbCl _x Br _3-x (0≤x, y≤1) can do.

Since the active layer 210 can be formed using various other ferroelectric materials, descriptions of all examples thereof will be omitted. Additionally, when forming the active layer 210, the ferroelectric material may be doped with various other materials to include additional functions or improve electrical properties.

The active layer 210 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 210 can maintain its polarization state even when the applied electric field is removed.

The application electrode 220 may be formed to apply an electric field to the active layer 210, and for example, may apply a voltage to the active layer 210. The application electrode 220 may be formed to apply an electric field to the active layer 210, and for example, may apply a voltage to the active layer 210. As an optional embodiment, the applying electrode 220 may be formed to contact the top surface of the active layer 210. A detailed description of the application electrode 220 is omitted since it can be applied the same or similar to that described in the above-described embodiment.

When the first electric field is applied to the active layer 210 through the applied electrode 220, at least one region of the active layer 210 may include a polarization region 210F, and this polarization region 210F is connected to the applied electrode 220. It may be in a form surrounding the application electrode 220. Additionally, this polarization region 210F may have a boundary line.

The variable low-resistance region VL2 may be formed in an area corresponding to the side of the boundary line of the polarization region 210F.

This variable low-resistance region VL2 may change into a region with lower resistance than other regions of the active layer 210.

For example, the polarization direction of one region of the active layer 210 and the region facing it with the variable low-resistance region VL2 in between may be opposite.

As a specific example, the polarization direction of the polarization region 210F overlapping the applied electrode 220 and another region of the active layer 210 adjacent to the variable low-resistance region VL2 (outside the polarization region 210F in FIG. 15) The polarization directions of the regions may be opposite to each other.

The variable low-resistance region VL2 is a region with low resistance and can form a path for current.

As an optional embodiment, the variable low-resistance region VL2 may correspond to one region of a plurality of domain walls provided in the active layer 210.

Additionally, this variable low-resistance region VL2 can be maintained if the polarization state of the polarization region 210F of the active layer 210 is maintained. That is, even if the first voltage applied to the active layer 210 through the application electrode 220 is removed, the state of the variable low-resistance region VL2, that is, the low-resistance state, can be maintained.

The connection electrode parts 231 and 232 may include one or more electrode members, for example, a first connection electrode member 231 and a second connection electrode member 232.

The connection electrode portions 231 and 232 may be formed to overlap the active layer 210 and be spaced apart from the application electrode 220.

The first connection electrode member 231 and the second connection electrode member 232 can be formed using various conductive materials.

As an optional embodiment, the first connection electrode member 231 and the second connection electrode member 232 may be terminal members that include input and output of electrical signals.

Also, as a specific example, the first connection electrode member 231 and the second connection electrode member 232 may include a source electrode or a drain electrode, and the first connection electrode member 231 is the source electrode and the second connection electrode. Member 232 may be a drain electrode.

The first connection electrode member 231 and the second connection electrode member 232 may be formed to have different electrical characteristics. For example, the first connection electrode member 231 and the second connection electrode member 232 may include materials having different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance area (VL2) and the first connection electrode member 231 are the characteristics of the electrical flow between the variable low-resistance area (VL2) and the second connection electrode member 232. It can be made to be different from .

As an optional embodiment, the work function values of the first connection electrode member 231 and the second connection electrode member 232 may be different. As a specific example, the work function of the first connection electrode member 231 may be smaller than the work function of the second connection electrode member 232.

For example, the first connection electrode member 231 and the second connection electrode member 232 may each include different metal materials, and the value of the work function of the metal material contained in the first connection electrode member 231 is The work function may be lower than that of the metal material contained in the second connection electrode member 232.

FIG. 16 is a diagram schematically showing the energy level of each region of the electronic device portion of FIG. 15.

Referring to FIG. 16, the energy level, for example, the Fermi energy level (Ef), of the first connection electrode member 231 and the second connection electrode member 232 made of a highly conductive material such as metal is shown, and the energy band The energy levels of the active layer 210 having a gap are shown.

Referring to FIG. 16, the work function values of the first connection electrode member 231 and the second connection electrode member 232 may be different, and specifically, the work function value of the first connection electrode member 231 represents a value smaller than the work function of the second connection electrode member 232.

As a specific example, the work function values of the first connection electrode member 231 and the second connection electrode member 232 are different, so that the first connection electrode member 231 and the second connection electrode member 232 and the active layer 210 ), the diagram representing the energy level may be tilted due to the difference in work function values of the first connection electrode member 231 and the second connection electrode member 232 and have the form shown in FIG. 16.

Through this energy state, the flow of electrons flows smoothly from right to left based on FIG. 16, that is, from the second connection electrode member 232 to the first connection electrode member 231, but the flow in the opposite direction is not smooth. It may not happen.

As a result, the flow of current flows smoothly from left to right based on FIG. 16, that is, from the first connection electrode member 231 to the second connection electrode member 232, but the flow in the opposite direction may not be smooth. there is.

The electronic device of this embodiment can form a polarization region with a polarization direction in one direction in the active layer by applying a voltage through an applied electrode, and form a variable low-resistance region at the boundary of the polarization region. For example, one side of the active layer region bordering the variable low-resistance region may have a polarization direction in one direction, and the other side may have a polarization direction in the opposite direction.

The variable low-resistance region is a region of lowered resistance, and current may flow through the first connection electrode member and the second connection electrode member.

The first connection electrode member and the second connection electrode member may have different electrical characteristics and, for example, different work function values.

Through this, the flow of electrons can be different between the first connection electrode member and the second connection electrode member and, for example, can be easily flowed in the direction from the second connection electrode member to the first connection electrode member. The smoothness of the flow of current from the member to the second connection electrode member can be improved.

Through this, it is possible to easily form an electronic device capable of precise control of the flow of current.

Figure 17 is a schematic cross-sectional view showing an electronic device according to another embodiment of the present invention.

The electronic device 200" of this embodiment may include an active layer 210", an applied electrode 220", a variable low-resistance region (VL), and one or more connection electrode portions 231" and 232". The electrode 220" may be formed on one side of the active layer 210", for example, may be formed to contact the one side.

The first connection electrode member 231" and the second connection electrode member 232" of the connection electrode portions 231" and 232" may be formed to face one side of the active layer 210", for example, The electrode 220" may be arranged to face the opposite side of the surface on which it is formed.

When the first electric field is applied to the active layer 210" through the applied electrode 220", at least one region of the active layer 210" may include a polarization region 210F', and this polarization region 210F' It may be shaped to surround the application electrode 220" with the application electrode 220" as the center. Additionally, this polarization region 210F' may have a boundary line.

A variable low-resistance region (VL) may be formed in an area corresponding to the side of this boundary line. This variable low-resistance region (VL) may change into a region with lower resistance than other regions of the active layer 210".

For example, the polarization direction of one region of the active layer 210" and the region facing it with the variable low-resistance region VL in between may be opposite.

As a specific example, the polarization direction of the polarization region 210F" overlapping with the applied electrode 220" and another region of the active layer 210" adjacent to the variable low-resistance region VL (polarization region 210F in FIG. 17) The polarization directions of the regions outside ') may be opposite to each other.

The variable low-resistance region (VL) is a region with low resistance and can form a path for current.

As an optional embodiment, the variable low-resistance region VL may correspond to one region of a plurality of domain walls provided in the active layer 210".

In addition, this variable low-resistance region VL can be maintained if the polarization state of the polarization region 210F' of the active layer 210" is maintained. That is, the active layer 210" is formed through the application electrode 220". Even if the first voltage applied to is removed, the state of the variable low-resistance region (VL), that is, the low-resistance state, can be maintained.

The first connection electrode member 231"" and the second connection electrode member 232" may be formed to have different electrical characteristics. For example, the first connection electrode member 231" and the second connection electrode member 232". 232" may include materials with different electrical properties.

Through this, the characteristics of the electrical flow between the variable low-resistance region (VL) and the first connection electrode member 231" are determined by the characteristics of the electrical flow between the variable low-resistance region (VL) and the second connection electrode member 232". It can be made to differ from the characteristics of .

As an optional embodiment, the work function values of the first connection electrode member 231" and the second connection electrode member 232" may be different. As a specific example, the work function of the first connection electrode member 231" may be smaller than the work function of the second connection electrode member 232".

For example, the first connection electrode member 231" and the second connection electrode member 232" may each include different metal materials, and the work function of the metal material contained in the first connection electrode member 231" The value of may be lower than the value of the work function of the metal material contained in the second connection electrode member 232".

Although not shown, the description of the energy levels in FIG. 16 described above can be applied as is to this embodiment.

FIG. 18 is a schematic plan view showing an electronic device according to another embodiment of the present invention, and FIG. 19 is a cross-sectional view taken along line VI-VI of FIG. 18.

Referring to FIGS. 18 and 19 , the electronic device 300 based on the variable low-resistance region may include an active layer 310, a gate 320, a source 331, and a drain 332.

The active layer 310 may include the above-described active layer material, for example, a spontaneously polarizable material. For example, the active layer 310 includes an insulating material and may include a ferroelectric material. That is, the active layer 310 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional example, the active layer 310 may include a perovskite-based material, for example, BaTiO _3, SrTiO _3, BiFe3, PbTiO3, PbZrO3, and SrBi2Ta2O9.

Also, as another example, the active layer 310 has an ABX3 structure, where A may include an alkyl group of CnH2n+1 and one or more materials selected from inorganics such as Cs and Ru capable of forming a perovskite solar cell structure, and B may include one or more materials selected from the group consisting of Pb, Sn, Ti, Nb, Zr, and Ce, and X may include a halogen material. As a specific example, the active layer 310 is CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbI _x Cl _3-x , MAPbI _3, CH ₃ NH ₃ PbI _x Br _3-x , CH ₃ NH ₃ PbClxBr _3-x , HC (NH ₂ ) ₂ PbI ₃ , HC(NH ₂ ) ₂ PbI _x Cl _3-x , HC(NH ₂ ) ₂ PbI _x Br _3-x , HC(NH ₂ ) ₂ PbCl _x Br _3-x , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI ₃ , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI _x Cl _3-x , (CH ₃ NH ₃ )(HC( NH ₂ ) ₂ ) _1-y PbI _x Br _3-x , or (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbCl _x Br _3-x (0≤x, y≤1) can do.

Since the active layer 310 can be formed using various other ferroelectric materials, descriptions of all examples thereof will be omitted. Additionally, when forming the active layer 310, the ferroelectric material may be doped with various other materials to include additional functions or improve electrical properties.

The active layer 310 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 310 can maintain its polarization state even when the applied electric field is removed.

The active layer 310 may include a second region 312 and a first region 311 that are adjacent to each other in the X-Y plane direction and have different polarization directions for at least a certain period of time depending on the applied voltage. The first region 311 may have polarization in a first direction, where the first direction is the thickness direction of the active layer 310, that is, the direction in which the second region 312 and the first region 311 are disposed. It may be in the Z-direction perpendicular to .

The second area 312 is located adjacent to the first area 311 in a direction perpendicular to the thickness, that is, in the It can have polarization aligned in two directions.

A gate 320 may be located on the active layer 310. Although not shown in the drawing, the gate 320 can be connected to a separate device to receive a gate signal.

The first region 311 can be polarized in the opposite direction to that of the second region 312 by the voltage applied to the gate 320.

In this way, a variable low-resistance region 340 may be formed between the second region 312 and the first region 311 having polarizations in opposite directions. The variable low-resistance region 340 as described above has a very small resistance compared to the second region 312 and/or the first region 311, and a current flow can be formed through this region.

This variable low-resistance region 340 may be formed according to the following embodiment.

First, the active layer 310 including a spontaneously polarizable material can be made to have overall polarization in the first direction. The entire active layer 310 is not necessarily limited to having polarization in the first direction, and at least a certain area of the active layer 310 facing the gate 320 may have polarization in the first direction. Optionally, polarization in the first direction can be achieved by applying an initialization electric field to the gate 320.

In this state, a first voltage is applied to the gate 320 for a first time to apply an electric field to the active layer 310 through the gate 320, so that a certain area opposite to the gate 320 is polarized in the second direction. It changes. The electric field applied to the gate 320 to change the direction of polarization can be adjusted by a first voltage, that is, the electric field applied to the gate 320 is greater than the coercive electric field of the spontaneously polarizable material forming the active layer 310. can be applied.

The active layer 310 may have a first thickness t1. At this time, the second region 312 is formed throughout the first thickness t1, and the magnitude of the first voltage applied to the gate 320 can be adjusted according to the first thickness t1. According to one embodiment, the first thickness t1 and the magnitude of the first voltage applied to the gate 320 may be proportional. That is, when the first thickness t1 is thick, the first voltage can be increased.

As can be seen in FIG. 19, the variable low-resistance region 340 may also be formed throughout the first thickness t1.

The area of the second region 312 formed in this way may be determined in proportion to the first time for which the first voltage is applied to the gate 320.

Therefore, in order to form the second region 312 of a desired area and/or size, an appropriate gate voltage, time, and first thickness (t1) of the second region 312 for the ferroelectric material must be experimentally and/or calculated. It can be decided in advance by

When the polarization direction of the second region 312 changes from the first direction to the second direction, a gap occurs between the first region 311 having polarization in the first direction and the second region 312 having polarization in the second direction. A variable low-resistance area 340 of a predetermined width may be formed. This variable low-resistance region 340 may be formed around the gate 320 .

The source and drain 331 and 332 may be formed to overlap the active layer 310 and be spaced apart from the gate 320 .

The source 331 and drain 332 may be formed to overlap the variable low-resistance region 340 . For example, the source 331 and the drain 332 may be formed to contact the variable low-resistance region 340.

The source 331 and the drain 332 may be formed to have different electrical characteristics. For example, the source 331 and the drain 332 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 340 and the source 331 can be made different from the characteristics of the electrical flow between the variable low-resistance region 340 and the drain 332.

As an optional embodiment, the work function values of the source 331 and the drain 332 may be different. As a specific example, the work function value of the source 331 may be smaller than the work function value of the drain 332.

For example, the source 331 and the drain 332 may each include different metal materials, and the value of the work function of the metal material contained in the source 331 is the work function of the metal material contained in the drain 332. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Through this, the flow of electrons can flow smoothly from the drain 332 to the source 331, and the flow in the opposite direction may not be smooth.

Figure 20 is a graph showing the voltage and current relationship between the first region and the variable low-resistance region.

Specifically, Figure 20 shows a state in which the current changes as the voltage increases in the first region and the variable low-resistance region.

That is, in FIG. 20, (a) shows a state in which the current changes as the voltage increases in the variable low-resistance region, and (b) shows a state in which the current changes as the voltage increases in the first region 311. .

Since the variable low-resistance region 340 has a very small resistance compared to the first region 311, it can be seen that current flows smoothly when voltage is applied.

The variable low-resistance region 340 formed as described above may not be erased over time.

When the source 331 and the drain 332 are positioned to contact the variable low-resistance region 340 formed in this way, current flows from the source 331 to the drain 332 through the variable low-resistance region 340. can be formed. Therefore, at this time, data can be written and, for example, can be read as 1.

Optionally, the variable low-resistance region 340 may be erased by making the polarization direction of the second region 312 the same as that of the first region 311 by the voltage applied to the gate 320.

That is, by applying the second voltage to the gate 320, the polarization direction of the second region 312 can be changed back to the first direction. Thereafter, the second voltage may be maintained for a second time to grow a region in which polarization is changed in the first direction in a plane direction, and the region in which polarization is changed in the first direction passes through the variable low-resistance region 340 to form a first region. When extended to the region 311, the variable low-resistance region 340 may disappear. In this case, current cannot flow from the source 331 to the drain 332, and therefore data can be erased at this time and can be read as 0.

At this time, the second voltage may be a different voltage from the first voltage, and according to one embodiment, it may be a voltage of the same magnitude and opposite polarity as the first voltage. The second time may be at least the first time or longer.

In addition, as another optional embodiment of erasing the variable low-resistance region 340, if the first voltage applied to the gate 320 is maintained to form the second region 312, the second region 312 It grows in a horizontal direction, and as a result, the overall polarization direction of the first region 311 is reversed and converted into the second region 312, and thus the variable low-resistance region 340 can disappear.

An electronic device based on a variable low-resistance region formed as described above can be used as a non-volatile memory device because the variable low-resistance region 340 can maintain its state even when power to the gate 320 is turned off.

Since the variable low-resistance region memory device can be written/erased about 10 ¹² times, it can have a memory lifespan about 10 ⁷ times longer than that of a memory device based on existing semiconductor devices.

As for memory speed, the variable low-resistance region memory device can be about 10 ^-9 sec, which can increase the memory speed by about 10 ⁶ times compared to memory devices based on existing semiconductor devices.

In this way, the variable low-resistance region memory device can be a memory device with excellent speed and lifespan.

In addition, since the position at which the variable low-resistance region 340 is formed can be adjusted depending on the gate voltage and/or application time, various memory devices can be designed and their thickness can be reduced compared to existing ferroelectric memory devices using ferroelectrics. can be achieved. In addition, there is an advantage in that the degree of device integration can be increased because the degree of freedom in memory design increases.

The variable low-resistance region 340 formed in this way can be formed in a closed loop centered on the gate 320. By placing the source 331 and the drain 332 in a part of the closed loop, the source 331 There may be two lines connecting the and drain 332. However, it is not necessarily limited to this, and if a gate is placed on one side of the active layer in the plane direction and the source and drain are placed on the other two adjacent sides, the variable low-resistance area can become a single line connecting the source and drain.

The source 331 and drain 332 as described above may be an electrode structure formed by patterning on the active layer 310, but the present invention is not necessarily limited thereto, and although not shown in the drawing, the active layer 310 It may be in contact with the variable low-resistance region 340 through a via hole formed in the covering insulating film.

Figure 21 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.

Referring to FIG. 21, the variable low-resistance region-based electronic device 400 has a source 431 and a drain 432 formed on a substrate 430, and an active layer ( 410) can be placed. For example, the electronic device 400 may be a memory device.

The substrate 430 may be formed of a semiconductor wafer, or, according to one embodiment, a silicon wafer. And the source 431 and drain 432 can be formed on the wafer by ion doping. Of course, although not shown in the drawing, external signal lines may be connected to the source 431 and drain 432 through separate vias.

In this structure, the gate voltage and application time can be determined so that the variable low-resistance region 440 is located corresponding to the regions of the source 431 and the drain 432 formed on the substrate 430.

The substrate 430 and the active layer 410 as described above may be bonded by a separate adhesive layer, but this is not necessarily limited, and the active layer 410 may be formed on the substrate 430. By implementing the active layer 410 as a thin film on the substrate 430 in this way, the memory device 400 can be further thinned, and existing memory device processes can be used to further increase the efficiency of the manufacturing process.

The variable low-resistance region 440 is formed between the first region 411 and the second region 412, which are regions with different polarization directions, and detailed details are omitted as they are similar to the above-described embodiment.

Although the first area 411 and the second area 412 have the same thickness, the present invention is not necessarily limited thereto.

The source and drain 431 and 432 may be formed to overlap the active layer 410 and be spaced apart from the gate 420 .

The source 431 and drain 432 may be formed to overlap the variable low-resistance region 440 . For example, the source 431 and the drain 432 may be formed to contact the variable low-resistance region 440.

The source 431 and the drain 432 may be formed to have different electrical characteristics. For example, the source 431 and the drain 432 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 440 and the source 431 can be made different from the characteristics of the electrical flow between the variable low-resistance region 440 and the drain 432.

As an optional embodiment, the work function values of the source 431 and the drain 432 may be different. As a specific example, the work function value of the source 431 may be smaller than the work function value of the drain 432.

For example, the source 431 and the drain 432 may each include different metal materials, and the value of the work function of the metal material contained in the source 431 is the work function of the metal material contained in the drain 432. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Figure 22 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.

For convenience of explanation, the description will focus on differences from the above-described embodiment.

Referring to FIG. 22, the variable low-resistance region-based electronic device 500 has a source 531 and a drain 532 formed on a substrate 530, and an active layer ( 510) can be placed. For example, the electronic device 500 may be a memory device.

In the electronic device 500 of the embodiment shown in FIG. 22 , the first region 511 may have a second thickness t2 that is thicker than the first thickness t1 of the second region 512 . This second thickness (t2) is a thickness in which the direction of polarization is not switched by the voltage applied to the gate 520, and accordingly, the variable low-resistance region 540 has a first thickness (t1) and a second thickness ( It can be formed at a location that is the boundary of t2).

As described above, the voltage applied to the gate 520 can be set to the voltage at which polarization switching occurs with respect to the first thickness t1, by creating a region formed in the active layer 510 with the second thickness t2. , the variable low-resistance region 540 is not formed in the second thickness t2 even depending on the intensity and time of the voltage applied to the gate 520, and the variable low-resistance region 540 is formed only in the region consisting of the first thickness t1. ) can be formed.

That is, as can be seen in FIG. 22, the variable low-resistance region 540 may be formed at a location that is the boundary between the first thickness t1 and the second thickness t2.

The active layer 510 may be arranged to overlap the source 531 and the drain 532. As a specific example, the active layer 510 may be in contact with the source 531 and the drain 532.

The source 531 and the drain 532 may be formed to overlap the active layer 510 and be spaced apart from the gate 520 .

The source 531 and drain 532 may be formed to overlap the variable low-resistance region 540 . For example, the source 531 and the drain 532 may be formed to contact the variable low-resistance region 540.

The source 531 and the drain 532 may be formed to have different electrical characteristics. For example, the source 531 and the drain 532 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 540 and the source 531 can be made different from the characteristics of the electrical flow between the variable low-resistance region 540 and the drain 532.

As an optional embodiment, the work function values of the source 531 and the drain 532 may be different. As a specific example, the work function value of the source 531 may be smaller than the work function value of the drain 532.

For example, the source 531 and the drain 532 may each include different metal materials, and the value of the work function of the metal material contained in the source 531 is the work function of the metal material contained in the drain 532. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Figure 23 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.

Referring to FIG. 23, the variable low-resistance region-based electronic device 600 has a source 631 and a drain 632 formed on a substrate 630, and an active layer ( 610) can be placed.

For example, the electronic device 600 may be a memory device.

Like the embodiment shown in FIG. 22 , the electronic device 600 of the embodiment shown in FIG. 23 also has a second thickness (t2) in which the first region 611 is thicker than the first thickness (t1) of the second region 612. You can have

At this time, depending on the time when the voltage is applied to the gate 620, as can be seen in FIG. 23, the inside of the first thickness t1 is varied from the boundary between the first thickness t1 and the second thickness t2. A low-resistance area 640 may be located. Accordingly, in the memory device 600 having this structure, the source 631 and the drain 632 can be formed inside the boundary between the first thickness t1 and the second thickness t2. Accordingly, even if the formation position of the variable low-resistance region 640 changes depending on the intensity and/or time of the gate 620 voltage, the variable low-resistance region 640 and the source 631/drain 632 are Can be electrically connected.

In the above-described embodiments, the gate is formed adjacent to the active layer, but the present invention is not necessarily limited thereto.

The variable low-resistance region 640 is formed between the first region 611 and the second region 612, which are regions with different polarization directions, and detailed details are omitted as they are similar to the above-described embodiment.

The source 631 and the drain 632 may be formed to overlap the active layer 610 and be spaced apart from the gate 620 .

The source 631 and drain 632 may be formed to overlap the variable low-resistance region 640 . For example, the source 631 and the drain 632 may be formed to contact the variable low-resistance region 640.

The source 631 and the drain 632 may be formed to have different electrical characteristics. For example, the source 631 and drain 632 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 640 and the source 631 can be made different from the characteristics of the electrical flow between the variable low-resistance region 640 and the drain 632.

As an optional embodiment, the work function values of the source 631 and the drain 632 may be different. As a specific example, the work function value of the source 631 may be smaller than the work function value of the drain 632.

For example, the source 631 and the drain 632 may each include different metal materials, and the value of the work function of the metal material contained in the source 631 is the work function of the metal material contained in the drain 632. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Figure 24 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.

Referring to FIG. 24 , in the electronic device 700, another film 750 may be further positioned between the active layer 710 and the gate 720. The film 750 may be an insulating film and may be a material different from the ferroelectric material forming the active layer 710.

The electronic device 700 may be, for example, a memory device.

In this case as well, the polarization direction of the second region 712 can be switched due to the influence of the electric field caused by the voltage applied to the gate 720. In this case, the gate 720 voltage and/or the polarization direction can be switched. Alternatively, the time may be obtained in advance by experiment and/or calculation. Since the description of the variable low-resistance region 740, source 731, and drain 732 is the same as that of the above-described embodiment, detailed description will be omitted.

The variable low-resistance region 740 is formed between the first region 711 and the second region 712, which are regions with different polarization directions, and detailed details are omitted as they are similar to the above-described embodiment.

The source 731 and the drain 732 may be formed to overlap the active layer 710 and be spaced apart from the gate 720 .

The source 731 and drain 732 may be formed to overlap the variable low-resistance region 740 . For example, the source 731 and the drain 732 may be formed to contact the variable low-resistance region 740.

The source 731 and the drain 732 may be formed to have different electrical characteristics. For example, the source 731 and the drain 732 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 740 and the source 731 can be made different from the characteristics of the electrical flow between the variable low-resistance region 740 and the drain 732.

As an optional embodiment, the work function values of the source 731 and the drain 732 may be different. As a specific example, the work function value of the source 731 may be smaller than the work function value of the drain 732.

For example, the source 731 and the drain 732 may each include different metal materials, and the value of the work function of the metal material contained in the source 731 is the work function of the metal material contained in the drain 732. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Figure 25 is a cross-sectional view of an electronic device based on a variable low-resistance region according to another embodiment of the present invention.

Referring to FIG. 25, the variable low-resistance region electronic device 800 has a source 831 and a drain 832 formed on a substrate 830, and an active layer 810 including a spontaneously polarizable material on the substrate 830. ) can be placed.

For example, the electronic device 800 may be a memory device.

According to the embodiment shown in FIG. 25, it includes a first gate 821 facing the active layer 810 and a second gate 822 located on the opposite side of the first gate 821 with respect to the active layer 810. can do.

In this case, the polarization direction of the second region 812 can be switched by the first gate 821 to form the variable low-resistance region 840. Accordingly, data writing becomes possible.

The variable low-resistance region 840 can be removed by switching the polarization direction of the second region 812 back to the same as that of the first region 811 by the second gate 822. As a result, erasing data becomes possible.

In this way, data can be read as 0/1 by the first gate 821 and the second gate 822.

All embodiments of the present specification described above are not limited to the respective illustrated embodiments, and of course can be applied in combination with each other.

In addition, of course, these embodiments can be selectively applied or modified to the embodiments described later.

The variable low-resistance region 840 is formed between the first region 811 and the second region 812, which are regions with different polarization directions, and detailed details are omitted as they are similar to the above-described embodiment.

Although the first area 811 and the second area 812 have the same thickness, the present invention is not necessarily limited thereto.

The source 831 and the drain 832 may be formed to overlap the active layer 810 and be spaced apart from the first gate 821 and the second gate 822 .

The source 831 and drain 832 may be formed to overlap the variable low-resistance region 840. For example, the source 831 and the drain 832 may be formed to contact the variable low-resistance region 840.

The source 831 and the drain 832 may be formed to have different electrical characteristics. For example, the source 831 and the drain 832 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region 840 and the source 831 can be made different from the characteristics of the electrical flow between the variable low-resistance region 840 and the drain 832.

As an optional embodiment, the work function values of the source 831 and the drain 832 may be different. As a specific example, the work function value of the source 831 may be smaller than the work function value of the drain 832.

For example, the source 831 and the drain 832 may each include different metal materials, and the value of the work function of the metal material contained in the source 831 is the work function of the metal material contained in the drain 832. It may be lower than the value of .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

Figures 26 and 27 are cross-sectional views schematically showing an example of an electronic device according to an embodiment of the present invention.

26 and 27, the electronic device 900 according to an embodiment of the present invention includes a first electrode 910, a second electrode 920 facing the first electrode 910, and a first electrode ( It may include an active layer 930 interposed between 910 and the second electrode 920.

At least one of the first electrode 910 and the second electrode 920 includes a first surface (S1) closest to the active layer 930 and a second surface (S2) furthest from the active layer 930, , At this time, the size of the horizontal cross-sectional area on the first surface (S1) may be smaller than the size of the horizontal cross-sectional area on the second surface (S2). As an example, at least one of the first electrode 910 and the second electrode 920 may include at least one protrusion 912 that protrudes in a direction toward the other electrode.

26 and 27 illustrate that the first electrode 910 includes one protrusion 912, but the present invention is not limited to this, and the protrusion 912 is attached to the second electrode 920. It may be formed on both the first electrode 910 and the second electrode 920. Additionally, a plurality of protrusions 912 may be formed. The protrusion 912 may be formed integrally with the first electrode 910.

The first electrode 910 and the second electrode 920 are made of metal materials such as platinum, gold, aluminum, silver, or copper, conductive polymers such as PEDOT:PSS or polyaniline, and indium oxide (e.g., In ₂ O). ₃ ), tin oxide (e.g. SnO ₂ ), zinc oxide (e.g. ZnO), indium tin oxide alloy (e.g. In ₂ O _{3 -} SnO ₂ ) or indium zinc oxide alloy (e.g. In ₂ O ₃ - It may contain metal oxides such as ZnO).

Active layer 930 may include a spontaneously polarizable material. For example, the active layer 930 includes an insulating material and may include a ferroelectric material. That is, the active layer 930 may include a material with a spontaneous electrical polarization (electric dipole) that can be reversed in the presence of an electric field.

As an optional example, the active layer 930 may include a perovskite-based material, for example, BaTiO _3, SrTiO _3, BiFe3, PbTiO3, PbZrO3, and SrBi2Ta2O9.

Also, as another example, the active layer 930 has an ABX3 structure, where A may include an alkyl group of CnH2n+1 and one or more materials selected from inorganics such as Cs and Ru capable of forming a perovskite solar cell structure, and B may include one or more materials selected from the group consisting of Pb, Sn, Ti, Nb, Zr, and Ce, and X may include a halogen material. As a specific example, the active layer 930 is CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbI _x Cl _3-x , MAPbI _3, CH ₃ NH ₃ PbI _x Br _3-x , CH ₃ NH ₃ PbClxBr _3-x , HC (NH ₂ ) ₂ PbI ₃ , HC(NH ₂ ) ₂ PbI _x Cl _3-x , HC(NH ₂ ) ₂ PbI _x Br _3-x , HC(NH ₂ ) ₂ PbCl _x Br _3-x , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI ₃ , (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbI _x Cl _3-x , (CH ₃ NH ₃ )(HC( NH ₂ ) ₂ ) _1-y PbI _x Br _3-x , or (CH ₃ NH ₃ )(HC(NH ₂ ) ₂ ) _1-y PbCl _x Br _3-x (0≤x, y≤1) can do.

This active layer 930 has spontaneous polarization, and the degree and direction of polarization can be controlled according to the application of an electric field. Additionally, the active layer 930 can maintain its polarization state even when the applied electric field is removed.

Meanwhile, the active layer 930 may include a first area (A1) vertically overlapping the first surface (S1) and a second area (A2) outside the first area (A1). As described above, since the horizontal cross-sectional area of the first surface (S1) closest to the active layer 930 is narrower than the horizontal cross-sectional area of the second surface (S2), the active layer 930 is vertical to the first surface (S1). The thickness of the overlapping first area A1 may be smaller than the thickness of the second area A2.

As shown in FIG. 26, the active layer 930 may be polarized in the first direction. For example, both the first area A1 and the second area A2 may have the same polarization in the first direction. In this state, current may not flow between the first electrode 910 and the second electrode 920 due to the active layer 930.

However, when a first voltage greater than the coercive voltage at which the charge of the hysteresis loop of the active layer 930 becomes 0 is applied to the first electrode 910 and the second electrode 920, as shown in FIG. 27 Likewise, the polarization direction of the first area A1 changes due to the first electric field generated between the first electrode 910 and the second electrode 920, and the active layer 930 is formed between the first area A1 and the second electrode 920. It can be divided into area A2.

At this time, the magnitude of the voltage for changing the polarization direction of the domain of the active layer 930 increases in proportion to the thickness of the active layer 930, so in the second area A2, which is thicker than the first area A1, The polarization direction of the active layer 930 does not change. That is, as a first voltage greater than the coercive voltage of the active layer 930 is applied to the first electrode 910 and the second electrode 920, polarization occurs in a second direction different from the first direction only in the first area A1. You can have For example, the first direction and the second direction may be opposite to each other.

Meanwhile, when the polarization directions in the first area (A1) and the second area (A2) are opposite, the unit lattice structure of the active layer 930 is localized at the boundary between the first area (A1) and the second area (A2). As this changes, an electrical polarization different from that of the first area (A1) and the second area (A2) occurs, and as a result, free electrons accumulate at the boundary between the first area (A1) and the second area (A2), causing a current to increase. A variable low-resistance region (C) capable of flowing may be created.

The variable low-resistance area C as described above is formed at the boundary between the first area A1 and the second area A2, and the first area A1 is changed by the area of the first surface S1. , the location where the variable low-resistance region C is generated can also be adjusted by the area of the first surface S1.

Meanwhile, when a second voltage to return the polarization direction of the first area A1 is applied to the first electrode 910 and the second electrode 920, a gap between the first electrode 910 and the second electrode 920 The first area A1 may have polarization in the first direction again due to the generated second electric field. The second voltage may be greater than the coercive voltage of the active layer 930 and may have a polarity opposite to the first voltage. As a result, the polarization difference between the first area A1 and the second area A2 may be eliminated.

When the polarization difference between the first area A1 and the second area A2 disappears, the variable low-resistance area C between the first area A1 and the second area A2 disappears. This state is the same as the state shown in FIG. 26. That is, since the first electrode 910 and the second electrode 920 are insulated by the active layer 930, even if a voltage is applied between the first electrode 910 and the second electrode 920, the first electrode 910 and the second electrode 920 are insulated. No current flows between 910 and the second electrode 920.

Therefore, the flow of current in the electronic device 900 can be controlled by controlling the voltage applied to the first electrode 910 and the second electrode 920, and the electronic device 900 can be controlled by controlling the flow of this current. Can be used for various purposes.

For example, the electronic device 900 can be used as a non-volatile memory. More specifically, as shown in FIG. 27, the polarization direction of the first area A1 is changed by applying a first voltage greater than the coercive voltage to the first electrode 910 and the second electrode 920. After the change, even if no voltage is applied to the first electrode 910 and the second electrode 920, the polarization direction of the first area A1 is maintained unchanged, and this state is expressed as a logic value of '1'. This can be understood as input.

Meanwhile, when the polarization direction of the first area (A1) changes, a variable low-resistance area (C) is formed, so when a read voltage is applied between the first electrode 910 and the second electrode 920, the current easily flows. It flows, and as a result, the logical value '1' can be read. At this time, in order to prevent the polarization of the first area A1 from being affected by the read voltage, the read voltage may be smaller than the coercive voltage of the active layer 930.

Additionally, when a second voltage is applied to the first electrode 910 and the second electrode 920 to return the polarization direction of the first area (A1), the polarization of the first area (A1) and the second area (A2) The direction becomes the same, and this state can be viewed as the logic value '0' being input.

In addition, when the polarization directions of the first area (A1) and the second area (A2) are the same, the variable low-resistance area (C) between the first area (A1) and the second area (A2) disappears. Accordingly, even if a voltage is applied between the first electrode 910 and the second electrode 920, no current flows between the first electrode 910 and the second electrode 920, which results in a logic value of '0'. You can read .

That is, when the electronic device 900 according to the present invention is used as a memory, the polarization state of the first area A1 is selectively changed by applying voltage to the first electrode 910 and the second electrode 920. , the logic values '1' and '0' can be read by measuring the current flowing in the fluctuating low-resistance region (C) that is created or destroyed accordingly, and data recording and playback speeds are faster than the method of measuring the residual polarization of existing domains. can be improved.

The first electrode 910 and the second electrode 920 may be formed to overlap the active layer 930 and be spaced apart from each other.

The first electrode 910 and the second electrode 920 may be formed to overlap the variable low-resistance region C in at least one region. For example, the first electrode 910 and the second electrode 920 may be formed to contact the variable low-resistance region C.

The first electrode 910 and the second electrode 920 may be formed to have different electrical characteristics. For example, the first electrode 910 and the second electrode 920 may include materials with different electrical characteristics.

Through this, the characteristics of the electrical flow between the variable low-resistance region C and the first electrode 910 will be different from the characteristics of the electrical flow between the variable low-resistance region C and the second electrode 920. You can.

As an optional embodiment, the work function values of the first electrode 910 and the second electrode 920 may be different. As a specific example, the work function of the first electrode 910 may be smaller than the work function of the second electrode 920.

For example, the first electrode 910 and the second electrode 920 may each include different metal materials, and the work function value of the metal material contained in the first electrode 910 is that of the second electrode 920. It may be lower than the value of the work function of the metal material contained in .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

In addition, according to the present invention, the variable low-resistance region C generated according to the application of an electric field can be formed only in a certain region. Therefore, the domain area where the polarization state changes in proportion to the application time of the electric field does not increase or expand, and the fluctuating low-resistance region (C) is formed only in limited locations, so when applied to non-volatile memory, the variable called electric field application time is used. There is an advantage that you don't have to consider it.

In addition, as the first electrode 910 and the second electrode 920 are stacked, the variable low-resistance region C is formed at the shortest distance connecting the first electrode 910 and the second electrode 920. , integration may be possible by reducing the size of the device. In addition, the size of the current flowing when reading logic values '1' and '0' is different, so the readability of the data can be improved.

Additionally, the electronic device 900 according to the present invention can form a circuit unit that generates and transmits various signals, and can also be used as a switching device. For example, the ON/OFF of current flow can be controlled by the creation and disappearance of the variable low-resistance region (C). In addition, the electronic device 900 according to the present invention can be applied in a simple structure to parts that require control of electrical signals, so it can be applied to various fields such as variable circuits, CPUs, and biochips.

As another example, the electronic device 900 according to the present invention can be used in a capacitor that can form various current path control regions. For example, if the distance between the first electrode 910 and the second electrode 920 facing each other is varied, it may vary depending on the size of the electric field applied to the first electrode 910 and the second electrode 920. The position at which the low-resistance region C is formed can be adjusted in various ways, thereby allowing various current path control regions to be formed in the storage battery.

The first electrode and the second electrode may include materials with different electrical properties, for example, metal materials with different work functions. As a specific example, the smooth flow of current from the first electrode to the second electrode can be improved by making the work function of the first electrode lower than that of the second electrode.

As a result, electrical control of electronic devices can be facilitated and control of current flow can be improved, thereby improving the electrical characteristics of electronic devices.

Figures 28 to 30 are cross-sectional views schematically showing other examples of the electronic devices of Figures 26 and 27, respectively.

First, referring to FIG. 28, the electronic device 900B includes a first electrode 910, a second electrode 920 facing the first electrode 910, and a first electrode 910 and a second electrode 920. It may include an active layer 930 interposed therebetween.

At least one of the first electrode 910 and the second electrode 920 may include a first surface (S1) closest to the active layer 930 and a second surface (S2) furthest from the active layer 930. You can. At this time, the size of the horizontal cross-sectional area on the first surface (S1) may be smaller than the size of the horizontal cross-sectional area on the second surface (S2).

For example, as shown in FIG. 28 , the first electrode 910 may include a protrusion 912 that protrudes toward the second electrode 920 . Additionally, at least a portion of the protrusion 912 may have a tapered shape. The tapered shape may include a first surface (S1). For example, the protrusion 912 may have a cone shape. However, the shape of the horizontal cross-section of the protrusion 912 is not limited to a circle, and may be various, such as a triangle, square, or polygon.

As such, when the protrusion 912 has a tapered shape including the first surface S1, a voltage to change the polarization of the first area A1 is applied between the first electrode 910 and the second electrode 920. When the electric field is concentrated between the first surface S1 and the second electrode 920, the polarization of the first area A1 can be changed more quickly and effectively.

The first electrode 910 and the second electrode 920 may be formed to overlap the active layer 930 and be spaced apart from each other.

The first electrode 910 and the second electrode 920 may be formed to overlap the variable low-resistance region C in at least one region. For example, the first electrode 910 and the second electrode 920 may be formed to contact the variable low-resistance region C.

The first electrode 910 and the second electrode 920 may be formed to have different electrical characteristics. For example, the first electrode 910 and the second electrode 920 may include materials with different electrical characteristics.

As an optional embodiment, the work function values of the first electrode 910 and the second electrode 920 may be different. As a specific example, the work function of the first electrode 910 may be smaller than the work function of the second electrode 920.

For example, the first electrode 910 and the second electrode 920 may each include different metal materials, and the work function value of the metal material contained in the first electrode 910 is that of the second electrode 920. It may be lower than the value of the work function of the metal material contained in .

For example, the description of the energy levels in FIG. 16 described above can be applied to this embodiment.

FIG. 29 shows an electronic device 900C having a structure in which the first electrode 910 has a tapered shape, similar to FIG. 28 . However, Figure 29 shows an example where the first electrode 910 has an overall tapered shape.

Additionally, FIG. 30 shows an example in which both the first electrode 910 and the second electrode 920 have a tapered shape. Specifically, the first electrode 910 and the second electrode 920 of the electronic device 900D of FIG. 30 include a first surface (S1) and a second surface (S2), respectively, and the first electrode 910 The first area A1 of the active layer 930 may be defined between the first surface S1 of the second electrode 920 and the first surface S1 of the second electrode 920 . At this time, it is preferable that the areas of the first surface S1 of the first electrode 910 and the first surface S1 of the second electrode 920 facing each other are the same for effective electric field induction.

Figures 31 to 36 are cross-sectional views schematically showing another example of the electronic device of Figures 26 and 27, respectively.

31 to 36 show the shape of the protrusion 912 of the first electrode 910. However, as described above, the present invention is designed to use the first electrode (910 in FIG. 26) and/or the second electrode (910 in FIG. 26). Since 920 may have an overall tapered shape, and the protrusion 912 may be formed integrally with the first electrode (910 in FIG. 26) and/or the second electrode (920 in FIG. 26), the protrusion 912 is hereinafter referred to as ) may be understood as a part of the first electrode 910 and/or the second electrode 920.

FIG. 31 is a cross-sectional view schematically showing an example of the II' cross-section of the electronic device of FIG. 26.

FIG. 31 shows an example in which both the protrusion 912 and the active layer 930 of the electronic device 900E have circular cross-sections.

FIG. 32 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.

FIG. 32 is a cross-sectional view of the protrusion 912 of the electronic device 900F and the active layer 930 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.

FIG. 33 shows an example in which both the protrusion 912 and the active layer 930 of the electronic device 900G have a rectangular cross-section. That is, the protrusion 912 and the active layer 930 are not limited to the above shapes and may have various shapes.

FIG. 34 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.

Figure 34 shows an electronic device 900H including a first protrusion 912a and a second protrusion 912b. The first protrusion 912a and the second protrusion 912b may be spaced apart from each other, and different voltages may be applied to them. For example, when the second electrode (920 in FIG. 26) is formed integrally, two variable low-resistance regions (C in FIG. 27) may be formed, so when the electronic device 900H is used as a memory, the logic value '0', '1', '2', and '3' can be recorded and read.

FIG. 35 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.

FIG. 35 shows an electronic device 900I including a first protrusion 912a, a second protrusion 912b, a third protrusion 912c, and a fourth protrusion 912d. The first to fourth protrusions 912a to 912d may be electrically separated from each other. Additionally, the second electrode (920 in FIG. 30) facing the first protrusion 912a, second protrusion 912b, third protrusion 912c, and fourth protrusion 912d may also be separated. Accordingly, when the electronic device 900H is used as a memory, the amount of data processed by the electronic device 900H may increase.

FIG. 36 is a cross-sectional view schematically showing another example of the II' cross-section of the electronic device of FIG. 26.

FIG. 36 shows an example in which the protrusion 912 of the electronic device 900J extends in one direction.

As described above, each electronic device has a different current value in each case and can store various information accordingly. Additionally, current control can be facilitated by controlling the electrical characteristics of the first electrode and the second electrode.

As such, the present invention has been described with reference to the embodiments shown in the drawings, but these are merely illustrative, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. . Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the attached patent claims.

Specific implementations described in the embodiments are examples and do not limit the scope of the embodiments in any way. Additionally, if there is no specific mention such as “essential,” “important,” etc., it may not be a necessary component for the application of the present invention.

In the specification of the embodiment (particularly in the claims), the use of the term “above” and similar referential terms may refer to both the singular and the plural. In addition, when a range is described in an example, the invention includes the application of individual values within the range (unless there is a statement to the contrary), and is the same as describing each individual value constituting the range in the detailed description. . Lastly, unless the order of the steps constituting the method according to the embodiment is clearly stated or there is no description to the contrary, the steps may be performed in an appropriate order. The embodiments are not necessarily limited by the order of description of the steps above. The use of any examples or illustrative terms (e.g., etc.) in the embodiments is merely for describing the embodiments in detail, and unless limited by the claims, the scope of the embodiments is not limited by the examples or illustrative terms. That is not the case. Additionally, those skilled in the art will recognize that various modifications, combinations and changes may be made depending on design conditions and factors within the scope of the appended claims or their equivalents.

100, 200, 300: Electronic devices
110, 210, 310: active layer
120, 220, 320: applying electrode
VL, VL1, VL2, C: Variable low-resistance region

Claims (2)

an active layer comprising a spontaneously polarizable material;
an applied electrode disposed adjacent to the active layer;
a polarization region formed in the active layer by applying an electric field to the active layer through the applying electrode;
one or more variable low-resistance regions including a region corresponding to a boundary of the polarization region and having lower electrical resistance than other adjacent regions;
a first electrode spaced apart from the applying electrode and connected to the variable low-resistance region; and
a second electrode spaced apart from the applying electrode, connected to the variable low-resistance region, and having different electrical characteristics from the first electrode;
The variable low-resistance region includes a region formed to correspond to the entire thickness of the active layer in at least one region of the active layer,
The variable low-resistance area is controlled to have a shape surrounding the applying electrode,
The second electrode has a different work function value from the first electrode,
The second electrode, which has a different work function from the first electrode, is disposed to overlap the variable low-resistance region in the thickness direction of the active layer and not to overlap the first electrode.
Electronic devices based on variable low-resistance regions. an active layer comprising a spontaneously polarizable material;
a first electrode disposed on one side of the active layer;
a second electrode facing the first electrode and facing the opposite side of the active layer facing the first electrode;
a protrusion formed on at least one of the first electrode and the second electrode;
a polarization region formed in the active layer by applying an electric field to the active layer through the first electrode or the second electrode;
one or more variable low-resistance regions including a region corresponding to a boundary of the polarization region and having lower electrical resistance than other adjacent regions;
The second electrode has a different work function value from the first electrode,
The variable low-resistance area has a shape corresponding to the protrusion.
Electronic devices based on variable low-resistance regions.

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