Resistive random access memory

Abstract

The embodiment of the utility model discloses a resistive random access memory. The resistive random access memory comprises a first electrode, a second electrode, a resistive material layer, a plurality of first table-shaped convex microstructures and a plurality of second table-shaped convex microstructures, the resistive material layer comprises a first surface and a second surface which deviate from each other; each first table-shaped convex microstructure is located on one side surface of the first electrode, and the first table-shaped convex microstructure is embedded into the first surface of the resistive material layer; each second table-shaped convex microstructure is located on one side surface of the second electrode, and the second table-shaped convex microstructures are embedded into the second surface of the resistive material layer; the number of the first table-shaped protruding microstructures and the number of the second table-shaped protruding microstructures are the same and are arranged in a one-to-one correspondence mode. According to the resistive random access memory, an electric field can be concentrated on the table-shaped convex microstructures, the probability of forming conductive filaments at the table-shaped convex microstructures is increased, the randomness of formation and fracture of the conductive filaments is inhibited, and the uniformity, the stability and the reliability of the resistive random access memory are improved.

Description

Technical Field

[0001] The embodiment of the utility model relates to the field of semiconductor storage technology, and in particular to a resistive random access memory. Background Art

[0002] Resistive memory has the characteristics of simple structure, fast read and write speed, low operating power consumption, high storage density, and multi-value storage. Therefore, resistive memory has gradually become the research focus of general-purpose memory.

[0003] Resistive memory can realize data storage by utilizing the electrical resistive switching characteristics. It generally adopts a stacked structure of an upper electrode, a resistive material layer and a lower electrode. Its working principle is to change the movement direction of ions or vacancies in the resistive material layer by controlling the voltage magnitude or polarity between the upper electrode and the lower electrode, and correspondingly form or destroy conductive filaments, thereby changing the resistance state of the resistive memory. Exemplarily, during the resistive switching process, ions or vacancies in the resistive material layer migrate to form conductive filaments. When the conductive filaments connect the upper electrode and the lower electrode, the resistive memory enters a low-resistance state; when the voltage magnitude or polarity between the upper electrode and the lower electrode is changed, the conductive filaments break, and the resistive memory enters a high-resistance state, thereby realizing a change in the resistance value of the resistive memory, that is, realizing data storage of the resistive memory.

[0004] However, since the formation and breaking of the conductive filaments in the resistive memory are random, the conductive filaments are dispersed, and the morphology and distribution of the conductive filaments in multiple resistive switching processes are different, the stability and reliability of the resistive memory are poor. Utility Model Content

[0005] The embodiment of the utility model provides a resistive random access memory, wherein the terrace-shaped protruding microstructure is more suitable for the formation of conductive filaments, thereby suppressing the randomness of the formation and fracture of the conductive filaments and improving the stability and reliability of the resistive random access memory.

[0006] The embodiment of the utility model provides a resistive memory, comprising a first electrode, a second electrode, a resistive material layer, a plurality of first terrace-shaped protruding microstructures and a plurality of second terrace-shaped protruding microstructures;

[0007] The resistive material layer comprises a first surface and a second surface which are opposite to each other;

[0008] Each of the first terrace-shaped protruding microstructures is located on a side surface of the first electrode, and the first terrace-shaped protruding microstructures are embedded in the first surface of the resistive material layer;

[0009] Each of the second terrace-shaped protruding microstructures is located on a side surface of the second electrode, and the second terrace-shaped protruding microstructures are embedded in the second surface of the resistive material layer;

[0010] The number of the first terrace-shaped convex microstructures is the same as the number of the second terrace-shaped convex microstructures and they are arranged in one-to-one correspondence, and the orthographic projection of the first terrace-shaped convex microstructure on the first surface overlaps with the orthographic projection of the second terrace-shaped convex microstructure on the first surface;

[0011] In a first direction, there is a distance between the first terrace-shaped protruding microstructure and the second terrace-shaped protruding microstructure; wherein the first direction is parallel to the thickness direction of the resistive material layer.

[0012] Optionally, in the first direction, the thickness of each of the first terrace-shaped protrusion microstructures is the same, the thickness of each of the second terrace-shaped protrusion microstructures is the same, and the thickness of the first terrace-shaped protrusion microstructure is the same as the thickness of the second terrace-shaped protrusion microstructure.

[0013] Optionally, the resistive material layer includes a plurality of resistive switching units;

[0014] The number of the resistive switching units, the number of the first terrace-shaped protruding microstructures and the number of the second terrace-shaped protruding microstructures are the same and are arranged in one-to-one correspondence, and the orthographic projection of the resistive switching unit on the first surface, the orthographic projection of the first terrace-shaped protruding microstructure on the first surface and the orthographic projection of the second terrace-shaped protruding microstructure on the first surface overlap;

[0015] In the first direction, at least two of the resistive switching units have different thicknesses.

[0016] Optionally, in the first direction, at least two of the first terrace-shaped protrusion microstructures have different thicknesses, at least two of the second terrace-shaped protrusion microstructures have different thicknesses, and the thickness of the first terrace-shaped protrusion microstructures with overlapping orthographic projections in one-to-one correspondence is the same as the thickness of the second terrace-shaped protrusion microstructures.

[0017] Optionally, along the second direction, the thickness of each of the first terrace-shaped protruding microstructures decreases sequentially, and the thickness of each of the second terrace-shaped protruding microstructures decreases sequentially; wherein the second direction is perpendicular to the thickness direction of the resistive material layer.

[0018] Optionally, the first electrode includes a plurality of first sub-electrodes;

[0019] The number of the first sub-electrodes is the same as the number of the first terrace-shaped protruding microstructures and they are arranged in one-to-one correspondence, and the orthographic projection of the first sub-electrodes on the first surface overlaps with the orthographic projection of the first terrace-shaped protruding microstructures on the first surface;

[0020] The first terrace-shaped protruding microstructures are located on a side surface of the first sub-electrode in a one-to-one correspondence.

[0021] Optionally, on one side surface of the first electrode, each of the first terrace-shaped protruding microstructures is arranged in an array;

[0022] The second terrace-shaped protruding microstructures are arranged in an array on one side surface of the second electrode.

[0023] Optionally, it also includes an argon ion implantation isolation layer;

[0024] The argon ion implantation isolation layer is located between adjacent first terrace-shaped protruding microstructures, and / or the argon ion implantation isolation layer is located between adjacent second terrace-shaped protruding microstructures.

[0025] Optionally, in the first direction, the thickness of the resistive material layer is in a range of 5 nm to 200 nm.

[0026] Optionally, in the first direction, the thickness of the first terrace protrusion microstructure is in a range of 1 nm to 5 nm, and the thickness of the second terrace protrusion microstructure is in a range of 1 nm to 5 nm.

[0027] An embodiment of the utility model provides a resistive memory, which comprises a first electrode, a second electrode, a resistive material layer, a plurality of first terrace-shaped protruding microstructures and a plurality of second terrace-shaped protruding microstructures; the resistive material layer comprises a first surface and a second surface which are opposite to each other; each first terrace-shaped protruding microstructure is located on a side surface of the first electrode, and the first terrace-shaped protruding microstructure is embedded in the first surface of the resistive material layer; each second terrace-shaped protruding microstructure is located on a side surface of the second electrode, and the second terrace-shaped protruding microstructure is embedded in the second surface of the resistive material layer; the number of the first terrace-shaped protruding microstructures is the same as the number of the second terrace-shaped protruding microstructures and they are arranged in a one-to-one correspondence, and the orthographic projection of the first terrace-shaped protruding microstructure on the first surface overlaps with the orthographic projection of the second terrace-shaped protruding microstructure on the first surface; in a first direction, there is a spacing between the first terrace-shaped protruding microstructure and the second terrace-shaped protruding microstructure; wherein the first direction is parallel to the thickness direction of the resistive material layer. The resistive random access memory is provided with a terrace-shaped protruding microstructure on one side surface of the upper electrode and the lower electrode respectively, and the terrace-shaped protruding microstructure is embedded in the resistive random access material layer, so that the electric field can be concentrated on the terrace-shaped protruding microstructure, thereby increasing the probability of forming conductive filaments at the terrace-shaped protruding microstructure, effectively suppressing the randomness of the formation and fracture of the conductive filaments, controlling the number of conductive filaments formed and the formation and fracture paths of the conductive filaments, and improving the uniformity, stability and reliability of the resistive random access memory. In addition, the terrace-shaped protruding microstructure is provided on one side surface of the upper electrode and the lower electrode respectively, thereby relatively shortening the distance between the upper electrode and the lower electrode. Under the premise of ensuring the stability of the formation and fracture of the conductive filaments, the Set voltage (which can be understood as the voltage of the resistive random access memory from a high resistance state to a low resistance state) and the Reset voltage (which can be understood as the voltage of the resistive random access memory from a low resistance state to a high resistance state) applied to the upper electrode or the lower electrode can be effectively reduced, thereby reducing the operating power consumption of the resistive random access memory and extending the service life of the resistive random access memory. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a structural schematic diagram of a resistive random access memory provided by an embodiment of the utility model;

[0030] Figure 2 It is a schematic diagram of the structure of another resistive random access memory provided by an embodiment of the utility model;

[0031] Figure 3This is a structural schematic diagram of another resistive random access memory provided by an embodiment of the utility model;

[0032] Figure 4 It is a structural schematic diagram of a first electrode and a first terrace-shaped protruding microstructure provided by an embodiment of the utility model;

[0033] Figure 5 This is a schematic structural diagram of a second electrode and a second terrace-shaped protruding microstructure provided in an embodiment of the utility model;

[0034] Figure 6 This is a schematic diagram of the structure of another resistive random access memory provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0036] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. It should be noted that the directional words such as "upper", "lower", "left", "right" and the like described in the embodiments of the present invention are described at the angles shown in the accompanying drawings and should not be understood as limitations on the embodiments of the present invention. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also indirectly formed "on" or "under" another element through an intermediate element. The terms "first", "second" and the like are only used for descriptive purposes and do not represent any order, quantity or importance, but are only used to distinguish different components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific circumstances.

[0037] The term "including" and its variations used in the present invention are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment".

[0038] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish the corresponding contents, and are not used to limit the order or interdependence.

[0039] It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0040] Figure 1 is a schematic diagram of a resistive random access memory provided by an embodiment of the present utility model, such as Figure 1 As shown, the resistive memory comprises a first electrode 10, a second electrode 20, a resistive material layer 30, a plurality of first terrace-shaped protruding microstructures 11 and a plurality of second terrace-shaped protruding microstructures 21; the resistive material layer 30 comprises a first surface and a second surface which are opposite to each other; each first terrace-shaped protruding microstructure 11 is located on a side surface of the first electrode 10, and the first terrace-shaped protruding microstructure 11 is embedded in the first surface of the resistive material layer 30; each second terrace-shaped protruding microstructure 21 is located on a side surface of the second electrode 20, and the second terrace-shaped protruding microstructure 21 is embedded in the first surface of the resistive material layer 30; The first terrace-shaped protrusion microstructure 21 is embedded in the second surface of the resistive material layer 30; the number of the first terrace-shaped protrusion microstructures 11 is the same as the number of the second terrace-shaped protrusion microstructures 21 and they are arranged in one-to-one correspondence, and the orthographic projection of the first terrace-shaped protrusion microstructure 11 on the first surface overlaps with the orthographic projection of the second terrace-shaped protrusion microstructure 21 on the first surface; in the first direction X, there is a spacing between the first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21; wherein the first direction X is parallel to the thickness direction of the resistive material layer 30.

[0041] Specifically, the resistive memory includes a first electrode 10, a second electrode 20, a resistive material layer 30, a plurality of first terrace-shaped protruding microstructures 11 and a plurality of second terrace-shaped protruding microstructures 21. Among them, each first terrace-shaped protruding microstructure 11 is located on a side surface of the first electrode 10, and each first terrace-shaped protruding microstructure 11 can be fixedly connected to the first electrode 10. Exemplarily, the first terrace-shaped protruding microstructure 11 includes a first sub-surface (which can be understood as an upper surface) and a second sub-surface (which can be understood as a lower surface), and the area of ​​the first sub-surface is smaller than the area of ​​the second sub-surface. In a specific embodiment, the second sub-surface of the first terrace-shaped protruding microstructure 11 is fixedly connected to the first electrode 10. Exemplarily, the number and position arrangement of the first terrace-shaped protruding microstructure 11 can be determined according to actual data storage needs. Similarly, each second terrace-shaped protruding microstructure 21 is located on a side surface of the second electrode 20, and each second terrace-shaped protruding microstructure 21 can be fixedly connected to the second electrode 20. Exemplarily, the second terrace-shaped protruding microstructure 21 includes a third sub-surface (which can be understood as an upper surface) and a fourth sub-surface (which can be understood as a lower surface), and the area of ​​the third sub-surface is smaller than the area of ​​the fourth sub-surface. In a specific embodiment, the fourth sub-surface of the second terrace-shaped protruding microstructure 21 is fixedly connected to the second electrode 20. Exemplarily, the number and position arrangement of the second terrace-shaped protruding microstructure 21 can be determined according to actual data storage needs.

[0042] The resistive material layer 30 includes a first surface and a second surface that are opposite to each other. In terms of the structural composition of the resistive memory, the first electrode 10 and the second electrode 20 are respectively located on two sides of the resistive material layer 30 that are opposite to each other, that is, exemplarily, the first electrode 10 is located on one side of the first surface of the resistive material layer 30, and the first terrace-shaped protruding microstructure 11 is embedded in the first surface of the resistive material layer 30, and the second electrode 20 is located on one side of the second surface of the resistive material layer 30, and the second terrace-shaped protruding microstructure 21 is embedded in the second surface of the resistive material layer 30. In a specific embodiment, the first sub-surface of the first terrace-shaped protruding microstructure 11 is embedded in the first surface of the resistive material layer 30, and the third sub-surface of the second terrace-shaped protruding microstructure 21 is embedded in the second surface of the resistive material layer 30. In this way, Figure 1 As shown, the first electrode 10 can be understood as an upper electrode, and the first terrace-shaped protruding microstructure 11 on one side of the first electrode 10 is embedded in the resistive material layer 30 in an "inverted trapezoidal shape", and the second electrode 20 can be understood as a lower electrode, and the second terrace-shaped protruding microstructure 21 on one side of the second electrode 20 is embedded in the resistive material layer 30 in a "positive trapezoidal shape". Of course, the resistive memory can also be inverted, the first electrode 10 can also be the lower electrode, and the second electrode 20 can also be the upper electrode. This embodiment is only an example here and is not limited.

[0043] As described above, this embodiment can be understood as adding a first terrace-shaped protruding microstructure 11 to the structure of the existing first electrode 10, and adding a second terrace-shaped protruding microstructure 21 to the structure of the existing second electrode 20. Also, the number of the first terrace-shaped protruding microstructures 11 is the same as the number of the second terrace-shaped protruding microstructures 21 and they are arranged in a one-to-one correspondence, that is, any first terrace-shaped protruding microstructure 11 on a side surface of the first electrode 10 can find a corresponding second terrace-shaped protruding microstructure 21 on a side surface of the second electrode 20, and the orthographic projections of the one-to-one corresponding first terrace-shaped protruding microstructures 11 on the first surface overlap with the orthographic projections of the second terrace-shaped protruding microstructures 21 on the first surface. In a specific embodiment, taking a corresponding first terrace-shaped protrusion microstructure 11 and a second terrace-shaped protrusion microstructure 21 as examples for description, the orthographic projection of the first sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface overlaps with the orthographic projection of the third sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface, the orthographic projection of the second sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface overlaps with the orthographic projection of the fourth sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface, and the orthographic projection of the first sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface is located in the orthographic projection of the second sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface, and the orthographic projection of the third sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface is located in the orthographic projection of the fourth sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface. Exemplarily, in another specific embodiment, taking a corresponding first terrace-shaped protrusion microstructure 11 and a second terrace-shaped protrusion microstructure 21 as examples for description, the orthographic projection of the first sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface completely coincides with the orthographic projection of the third sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface, and the orthographic projection of the second sub-surface of the first terrace-shaped protrusion microstructure 11 on the first surface completely coincides with the orthographic projection of the fourth sub-surface of the second terrace-shaped protrusion microstructure 21 on the first surface, that is, the area of ​​the first sub-surface of the first terrace-shaped protrusion microstructure 11 is the same as the area of ​​the third sub-surface of the second terrace-shaped protrusion microstructure 21, and the area of ​​the second sub-surface of the first terrace-shaped protrusion microstructure 11 is the same as the area of ​​the fourth sub-surface of the second terrace-shaped protrusion microstructure 21.

[0044] Further, in the first direction X parallel to the thickness direction of the resistive material layer 30, there is a spacing between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21. That is, taking a corresponding first terrace-shaped protruding microstructure 11 and a second terrace-shaped protruding microstructure 21 as an example for explanation, the first sub-surface of the first terrace-shaped protruding microstructure 11 is not in contact with the third sub-surface of the second terrace-shaped protruding microstructure 21, and conductive filaments can be formed in the area between the first sub-surface of the first terrace-shaped protruding microstructure 11 and the third sub-surface of the second terrace-shaped protruding microstructure 21 later, thus limiting the formation area of ​​the conductive filaments and suppressing the randomness of the formation of the conductive filaments. In a specific embodiment, the working principle of the resistive random access memory is that a positive electric field is applied between the first electrode 10 and the second electrode 20, and the first terrace-shaped protruding microstructure 11 can be oxidized into metal ions under the action of the positive electric field, and the metal ions move along the electric field line direction to the corresponding second terrace-shaped protruding microstructure 21, and the metal ions are reduced to atoms at the second terrace-shaped protruding microstructure 21. The atoms gradually accumulate and form a conductive filament between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21. When the conductive filament electrically connects the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21, the resistive random access memory is in a low-resistance state. Afterwards, a reverse electric field is applied between the first electrode 10 and the second electrode 20, and the conductive filament breaks, the electrical connection between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 fails, and the resistive random access memory is in a high-resistance state. It should be noted that the forward electric field and the reverse electric field described in this embodiment are two relative concepts, and the polarities of the forward electric field and the reverse electric field are opposite. Of course, voltages of other magnitudes and polarities can also be applied according to actual needs.

[0045] In addition, a first terrace-shaped protruding microstructure 11 is additionally added to the structure of the first electrode 10, and a second terrace-shaped protruding microstructure 21 is additionally added to the structure of the second electrode 20, which relatively shortens the distance between the first electrode 10 and the second electrode 20. Under the premise of ensuring the stability of the formation and breakage of the conductive filaments, the Set voltage (which can be understood as the voltage at which the resistive memory changes from a high-resistance state to a low-resistance state) and the Reset voltage (which can be understood as the voltage at which the resistive memory changes from a low-resistance state to a high-resistance state) applied to the first electrode 10 or the second electrode 20 can be effectively reduced. That is, a smaller Set voltage (which can be understood as the voltage at which the resistive memory changes from a high-resistance state to a low-resistance state) can be used to achieve the formation of conductive filaments, and a smaller Reset voltage (which can be understood as the voltage at which the resistive memory changes from a low-resistance state to a high-resistance state) can be used to achieve the breakage of conductive filaments, thereby reducing the operating power consumption of the resistive memory.

[0046] In addition, illustratively, the shape of the first terrace-shaped protruding microstructure 11 may be a truncated cone, a prism, etc., and the shape of the second terrace-shaped protruding microstructure 21 may be a truncated cone, a prism, etc. This embodiment is only taken as an example and is not limited. It should be noted that if the protruding microstructures on the surfaces of the first electrode 10 and the second electrode 20 are conical protruding microstructures, then between the conical protruding microstructure on one side surface of the first electrode 10 and the corresponding conical protruding microstructure on one side surface of the second electrode 20, although conductive filaments can be more effectively formed, reducing the randomness of the formation and breakage of the conductive filaments, the sharp structure at the top of the conical protruding microstructure may cause the problem of electric field concentration breakdown. The first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21 in the present embodiment can be understood as a part of the conical protrusion microstructure, with the top sharp part of the conical protrusion microstructure removed. The first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21 inherit the advantages of the conical protrusion microstructure. Conductive filaments can still be effectively formed between the first terrace-shaped protrusion microstructure 11 on the side surface of the first electrode 10 and the corresponding second terrace-shaped protrusion microstructure 21 on the side surface of the second electrode 20, which reduces the randomness of the formation and breakage of the conductive filaments and does not cause the problem of electric field concentration breakdown, thereby improving the uniformity, stability and reliability of the resistive random access memory.

[0047] According to the technical solution in the embodiment of the utility model, the resistive memory comprises a first electrode, a second electrode, a resistive material layer, a plurality of first terrace-shaped protruding microstructures and a plurality of second terrace-shaped protruding microstructures; the resistive material layer comprises a first surface and a second surface which are opposite to each other; each first terrace-shaped protruding microstructure is located on a side surface of the first electrode, and the first terrace-shaped protruding microstructure is embedded in the first surface of the resistive material layer; each second terrace-shaped protruding microstructure is located on a side surface of the second electrode, and the second terrace-shaped protruding microstructure is embedded in the second surface of the resistive material layer; the number of the first terrace-shaped protruding microstructures is the same as the number of the second terrace-shaped protruding microstructures and they are arranged in a one-to-one correspondence, and the orthographic projection of the first terrace-shaped protruding microstructure on the first surface overlaps with the orthographic projection of the second terrace-shaped protruding microstructure on the first surface; in the first direction, there is a spacing between the first terrace-shaped protruding microstructure and the second terrace-shaped protruding microstructure; wherein the first direction is parallel to the thickness direction of the resistive material layer. The resistive random access memory is provided with a terrace-shaped protruding microstructure on one side surface of the upper electrode and the lower electrode respectively, and the terrace-shaped protruding microstructure is embedded in the resistive random access material layer, so that the electric field can be concentrated on the terrace-shaped protruding microstructure, thereby increasing the probability of forming conductive filaments at the terrace-shaped protruding microstructure, effectively suppressing the randomness of the formation and fracture of the conductive filaments, controlling the number of conductive filaments formed and the formation and fracture paths of the conductive filaments, and improving the uniformity, stability and reliability of the resistive random access memory. In addition, the terrace-shaped protruding microstructure is provided on one side surface of the upper electrode and the lower electrode respectively, thereby relatively shortening the distance between the upper electrode and the lower electrode. Under the premise of ensuring the stability of the formation and fracture of the conductive filaments, the Set voltage (which can be understood as the voltage of the resistive random access memory from a high resistance state to a low resistance state) and the Reset voltage (which can be understood as the voltage of the resistive random access memory from a low resistance state to a high resistance state) applied to the upper electrode or the lower electrode can be effectively reduced, thereby reducing the operating power consumption of the resistive random access memory and extending the service life of the resistive random access memory.

[0048] Optionally, continue to refer to Figure 1 In the first direction X, the thickness of each first terrace-shaped protrusion microstructure 11 is the same, the thickness of each second terrace-shaped protrusion microstructure 21 is the same, and the thickness of the first terrace-shaped protrusion microstructure 11 is the same as the thickness of the second terrace-shaped protrusion microstructure 21 .

[0049] Specifically, the first direction X is parallel to the thickness direction of the resistive material layer 30. The thickness of each first terrace-shaped protruding microstructure 11 on one side surface of the first electrode 10 is the same, the thickness of each second terrace-shaped protruding microstructure 21 on one side surface of the second electrode 20 is the same, and the thickness of the first terrace-shaped protruding microstructure 11 is the same as the thickness of the second terrace-shaped protruding microstructure 21. Exemplarily, the thickness of each first terrace-shaped protruding microstructure 11 may be H1, and the thickness of each second terrace-shaped protruding microstructure 21 may be H1. In this way, the spacing between the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is the same, and the length of the conductive filament formed between the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is the same. Under the action of the electric field applied between the first electrode 10 and the second electrode 20, a conductive filament is formed in the area between the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21, or the conductive filament is broken.

[0050] In another specific embodiment, optionally, Figure 2 is a schematic diagram of the structure of another resistive random access memory provided by an embodiment of the utility model, such as Figure 2 As shown, the resistive material layer 30 includes a plurality of resistive units 31; the number of the resistive units 31, the number of the first terrace-shaped protruding microstructures 11 and the number of the second terrace-shaped protruding microstructures 21 are the same and are arranged in a one-to-one correspondence, and the orthographic projection of the resistive unit 31 on the first surface, the orthographic projection of the first terrace-shaped protruding microstructure 11 on the first surface and the orthographic projection of the second terrace-shaped protruding microstructure 21 on the first surface overlap; in the first direction X, the thicknesses of at least two resistive units 31 are different.

[0051] Specifically, the thickness of each first terrace-shaped protruding microstructure 11 on one side surface of the first electrode 10 is the same, the thickness of each second terrace-shaped protruding microstructure 21 on one side surface of the second electrode 20 is the same, and the thickness of the first terrace-shaped protruding microstructure 11 is the same as the thickness of the second terrace-shaped protruding microstructure 21. Exemplarily, the thickness of each first terrace-shaped protruding microstructure 11 may be H1, and the thickness of each second terrace-shaped protruding microstructure 21 may be H1. However, the thickness of at least part of the resistive variable unit 31 between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is different, that is, the spacing between the corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is not exactly the same, and the length of the conductive filament formed between the corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is not exactly the same. Exemplarily, Figure 2 The resistive material layer 30 shown includes four resistive units 31, and the thicknesses of the four resistive units 31 are H2, H3, H4, and H5, respectively, and H2, H3, H4, and H5 are different from each other. In other embodiments, at least two of H2, H3, H4, and H5 are the same. Of course, Figure 2 The number, position setting, and thickness setting of the resistive switching units 31 shown are all examples and are not limited here.

[0052] In this way, under the action of the electric field applied between the first electrode 10 and the second electrode 20, due to the different thicknesses of at least two resistive switching units 31, the lengths of the conductive filaments formed in the corresponding areas between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 are not completely the same, and the time for the conductive filaments to be formed in the corresponding areas between the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 is not completely the same, and the required Set voltage (which can be understood as the voltage at which the resistive switching memory changes from a high-resistance state to a low-resistance state) and Reset voltage (which can be understood as the voltage at which the resistive switching memory changes from a low-resistance state to a high-resistance state) are also different in magnitude or polarity, that is, the resistive switching memory can realize changes in several different resistance values, the resistive switching memory can realize conversion between a high-resistance state and a low-resistance state, and the resistive switching memory can realize the storage of several data, that is, multi-value storage, which effectively improves the storage density of the resistive switching memory.

[0053] Optionally, Figure 3 is a schematic diagram of the structure of another resistive random access memory provided by an embodiment of the present utility model. Figure 3 As shown, in the first direction X, at least two first terrace-shaped protrusion microstructures 11 have different thicknesses, at least two second terrace-shaped protrusion microstructures 21 have different thicknesses, and the thickness of the first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21 that overlap in one-to-one orthographic projection are the same.

[0054] Specifically, the first direction X is parallel to the thickness direction of the resistive material layer 30. The thicknesses of at least two first terrace-shaped protruding microstructures 11 on one side surface of the first electrode 10 are different, and the thicknesses of at least two second terrace-shaped protruding microstructures 21 on one side surface of the second electrode 20 are different, and the thickness of the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 that overlap in one-to-one correspondence are the same. Exemplarily, Figure 3 The first electrode 10 shown includes four first terrace-shaped protruding microstructures 11 on one side of the surface, and the thicknesses of the four first terrace-shaped protruding microstructures 11 are H6, H7, H8, and H9, respectively. The second electrode 20 includes four second terrace-shaped protruding microstructures 21 on one side of the surface, and the thicknesses of the four second terrace-shaped protruding microstructures 21 are H6, H7, H8, and H9, respectively, and H6, H7, H8, and H9 are different from each other. In other embodiments, at least two of H6, H7, H8, and H9 are the same. Of course, Figure 3 The number, position arrangement, and thickness arrangement of the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 are all examples and are not limited here.

[0055] In this way, the spacing between the corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 is different, the lengths of the conductive filaments formed between the corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 are different, the time for forming the conductive filaments between the corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 is different, the Set voltage (which can be understood as the voltage for the resistive memory to change from a high-resistance state to a low-resistance state) required for the formation of the conductive filaments between the corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 is different, and the Reset voltage (which can be understood as the voltage for the resistive memory to change from a low-resistance state to a high-resistance state) required for the breaking of the conductive filaments between the corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 is different. And, illustratively, the smaller the sum of the thicknesses of the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21, the longer the length of the conductive filament formed between the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21, and the larger the sum of the thicknesses of the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21, the shorter the length of the conductive filament formed between the one-to-one corresponding first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21. In this way, the Set voltage (which can be understood as the voltage at which the resistive random access memory changes from a high-resistance state to a low-resistance state) required for the formation of conductive filaments of different lengths is different, and the resistance value after the resistive random access process is also different, that is, the resistive random access memory can realize several different resistance value changes, the resistive random access memory can realize the conversion between the high-resistance state and the low-resistance state, and the resistive random access memory can realize the storage of several data, that is, multi-value storage, which effectively improves the storage density of the resistive random access memory.

[0056] Further, continue to refer to Figure 3 Along the second direction Y, the thickness of each first terrace-shaped protruding microstructure 11 decreases successively, and the thickness of each second terrace-shaped protruding microstructure 21 decreases successively; wherein the second direction Y is perpendicular to the thickness direction of the resistive material layer 30 .

[0057] Specifically, the first direction X is parallel to the thickness direction of the resistive material layer 30. The second direction Y is perpendicular to the thickness direction of the resistive material layer 30. It can be understood that the first direction X and the second direction Y are perpendicular to each other. The thickness of the first terraced protruding microstructure 11 with overlapping orthographic projections is the same as the thickness of the second terraced protruding microstructure 21. Along the second direction Y, the thickness of each first terraced protruding microstructure 11 decreases successively, and the thickness of each second terraced protruding microstructure 21 decreases successively. In this way, the length of the conductive filaments formed between the one-to-one corresponding first terraced protruding microstructure 11 and the second terraced protruding microstructure 21 is reduced successively, which is conducive to the reasonable control and monitoring of the data storage process of the resistive memory. By way of example, Figure 3 The thicknesses of the four first terrace-shaped protruding microstructures 11 are H6, H7, H8, and H9, respectively. The thicknesses of the four second terrace-shaped protruding microstructures 21 are H6, H7, H8, and H9, respectively. Furthermore, H6>H7>H8>H9.

[0058] It can be understood that, in another specific embodiment, along the second direction Y, the thickness of each first terrace-shaped protrusion microstructure 11 increases sequentially, and the thickness of each second terrace-shaped protrusion microstructure 21 increases sequentially. Alternatively, along the second direction Y, the thickness of each first terrace-shaped protrusion microstructure 11 can also change in other ways, and the thickness of each second terrace-shaped protrusion microstructure 21 can also change in other ways, which are not limited in this embodiment.

[0059] In another specific embodiment, the thickness of the first terrace-shaped protrusion microstructure 11 and the thickness of the second terrace-shaped protrusion microstructure 21 that overlap in one-to-one orthographic projections may be different, and the thickness of the resistive switching unit 31 between the first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21 that overlap in one-to-one orthographic projections may be different. In this way, the length of the conductive filament formed between the first terrace-shaped protrusion microstructure 11 and the second terrace-shaped protrusion microstructure 21 that overlap in one-to-one orthographic projections may be arbitrarily changed according to actual needs, so as to realize the multi-value storage of the resistive switching memory.

[0060] Optionally, continue to refer to Figure 1 , Figure 2 and Figure 3 The first electrode 10 includes a plurality of first sub-electrodes 12; the number of the first sub-electrodes 12 is the same as the number of the first terrace-shaped protruding microstructures 11 and they are arranged in one-to-one correspondence, and the orthographic projection of the first sub-electrode 12 on the first surface overlaps with the orthographic projection of the first terrace-shaped protruding microstructure 11 on the first surface; the first terrace-shaped protruding microstructures 11 are located on one side surface of the first sub-electrode 12 in a one-to-one correspondence.

[0061] Specifically, the number of the first sub-electrodes 12 is the same as the number of the first terrace-shaped protruding microstructures 11 and they are arranged in a one-to-one correspondence, and the orthographic projection of the first sub-electrode 12 on the first surface overlaps with the orthographic projection of the first terrace-shaped protruding microstructure 11 on the first surface. The first terrace-shaped protruding microstructures 11 are located on the side surface of the first sub-electrode 12 in a one-to-one correspondence. For example, the second sub-surface of the first terrace-shaped protruding microstructure 11 is fixedly connected to the corresponding first sub-electrode 12. The second electrode 20 can be a whole film layer structure. In this way, the voltages applied between at least two first sub-electrodes 12 and the second electrode 20 may be different in magnitude, and the time for the conductive filaments formed in the area between the one-to-one corresponding first terrace-shaped protruding microstructures 11 and the second terrace-shaped protruding microstructures 21 is not exactly the same, that is, the resistive random access memory can realize changes in several different resistance values, the resistive random access memory can realize the conversion between the high resistance state and the low resistance state, and the resistive random access memory can realize the storage of several data, that is, multi-value storage, which effectively improves the storage density of the resistive random access memory. In addition, illustratively, the number of first sub-electrodes 12 and the number of first terrace-shaped protruding microstructures 11 may be different, and a plurality of first terrace-shaped protruding microstructures 11 may be disposed on one side surface of any first sub-electrode 12. Of course, the first electrode 10 may also be a whole film layer structure.

[0062] Furthermore, the second electrode 20 may also include a plurality of second sub-electrodes, the number of the second sub-electrodes is the same as the number of the second terrace-shaped protruding microstructures 21 and is arranged in one-to-one correspondence, and the orthographic projection of the second sub-electrode on the first surface overlaps with the orthographic projection of the second terrace-shaped protruding microstructure 21 on the first surface; the second terrace-shaped protruding microstructures 21 are arranged in one-to-one correspondence on one side surface of the second sub-electrode. In addition, illustratively, the number of the second sub-electrodes may be different from the number of the second terrace-shaped protruding microstructures 21, and a plurality of second terrace-shaped protruding microstructures 21 may be arranged on one side surface of any second sub-electrode. This embodiment is only for example and is not limited here.

[0063] Optionally, Figure 4 is a schematic structural diagram of a first electrode and a first terrace-shaped protruding microstructure provided by an embodiment of the utility model, such as Figure 4 As shown, on one side surface of the first electrode 10, the first terrace-shaped protruding microstructures 11 are arranged in an array. Figure 5 : is a schematic diagram of the structure of a second electrode and a second terrace-shaped protruding microstructure provided by an embodiment of the utility model, such as Figure 5 As shown, on one side surface of the second electrode 20, the second terrace-shaped protruding microstructures 21 are arranged in an array.

[0064] Specifically, Figure 4 It can be understood as a schematic diagram of a top view of the structure before the first terrace-shaped protruding microstructure 11 on one side of the first electrode 10 is embedded in the resistive material layer 30. Figure 5 It can be understood as a schematic diagram of the top view of the structure before the second terrace-shaped protruding microstructure 21 on one side of the second electrode 20 is embedded in the resistive material layer 30. On one side surface of the first electrode 10, each first terrace-shaped protruding microstructure 11 is arranged in an array. For example, each first terrace-shaped protruding microstructure 11 can be arranged in m rows and n columns. On one side surface of the second electrode 20, each second terrace-shaped protruding microstructure 21 is arranged in an array. For example, each second terrace-shaped protruding microstructure 21 can also be arranged in m rows and n columns. Wherein, the number of rows m≥1, and the number of columns n≥1. For example, Figure 4 and Figure 5 The number of rows m shown in FIG. 1 is 3, the number of columns n is 3, the first terrace-shaped protruding microstructure 11 may be in a truncated cone shape, and the second terrace-shaped protruding microstructure 21 may be in a truncated cone shape.

[0065] Optionally, Figure 6 is a schematic diagram of the structure of another resistive random access memory provided by an embodiment of the present utility model. Figure 6 As shown, the resistive random access memory further includes an argon ion implantation isolation layer 40 ; the argon ion implantation isolation layer 40 is located between adjacent first mesa-shaped protruding microstructures 11 , and / or the argon ion implantation isolation layer 40 is located between adjacent second mesa-shaped protruding microstructures 21 .

[0066] Specifically, the resistive random access memory also includes an argon ion implantation isolation layer 40. The argon ion implantation isolation layer 40 can be prepared by ion implantation. The argon ion implantation isolation layer 40 can be located between adjacent first terrace-shaped raised microstructures 11, so that the argon ion implantation isolation layer 40 can effectively reduce the possibility of mutual interference in the formation of conductive filaments corresponding to adjacent first terrace-shaped raised microstructures 11. The argon ion implantation isolation layer 40 can also be located between adjacent second terrace-shaped raised microstructures 21, and the argon ion implantation isolation layer 40 can effectively reduce the possibility of mutual interference in the formation of conductive filaments corresponding to adjacent second terrace-shaped raised microstructures 21. Exemplarily, Figure 6 The argon ion implantation isolation layer 40 shown extends from the first electrode 10 to the second electrode 20. The argon ion implantation isolation layer 40 can be located between the formation areas of adjacent conductive filaments, effectively preventing interference between adjacent conductive filaments during the formation process. In addition, illustratively, the shape or size of the argon ion implantation isolation layer 40 can be determined according to the size of the first mesa-shaped protruding microstructure 11 adjacent thereto, and can be determined according to the size of the second mesa-shaped protruding microstructure 21 adjacent thereto, which is not limited in this embodiment.

[0067] Optionally, continue to refer to Figure 1-Figure 6In the first direction X, the thickness of the resistive material layer 30 is in the range of 5nm-200nm. Optionally, in the first direction X, the thickness of the first terrace protrusion microstructure 11 is in the range of 1nm-5nm, and the thickness of the second terrace protrusion microstructure 21 is in the range of 1nm-5nm.

[0068] Specifically, the material of the resistive material layer 30 can be any one of silicon oxide, germanium oxide, titanium oxide, hafnium oxide, zinc oxide, tungsten oxide, tantalum oxide, or a mixture thereof. The material of the first terrace-shaped protruding microstructure 11 and the second terrace-shaped protruding microstructure 21 can be any one of copper, aluminum, titanium, nickel, gold, platinum, tungsten, or a mixture thereof. In addition, the spacing between adjacent first terrace-shaped protruding microstructures 11 can range from 50nm to 50μm, and the spacing between adjacent second terrace-shaped protruding microstructures 21 can range from 50nm to 50μm. This embodiment is only for example and is not limited here. The size of the first terrace-shaped protruding microstructure 11, the size of the second terrace-shaped protruding microstructure 21, and the size of the resistive material layer 30 can all be determined according to actual needs.

[0069] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A resistive random access memory, characterized in that: It includes a first electrode, a second electrode, a resistive material layer, a plurality of first terrace-shaped protruding microstructures and a plurality of second terrace-shaped protruding microstructures; The resistive material layer comprises a first surface and a second surface which are opposite to each other; Each of the first terrace-shaped protruding microstructures is located on a side surface of the first electrode, and the first terrace-shaped protruding microstructures are embedded in the first surface of the resistive material layer; Each of the second terrace-shaped protruding microstructures is located on a side surface of the second electrode, and the second terrace-shaped protruding microstructures are embedded in the second surface of the resistive material layer; The number of the first terrace-shaped convex microstructures is the same as the number of the second terrace-shaped convex microstructures and they are arranged in one-to-one correspondence, and the orthographic projection of the first terrace-shaped convex microstructure on the first surface overlaps with the orthographic projection of the second terrace-shaped convex microstructure on the first surface; In a first direction, there is a distance between the first terrace-shaped protruding microstructure and the second terrace-shaped protruding microstructure; wherein the first direction is parallel to the thickness direction of the resistive material layer.

2. The resistive random access memory according to claim 1, characterized in that: In the first direction, each of the first terrace-shaped protrusion microstructures has the same thickness, each of the second terrace-shaped protrusion microstructures has the same thickness, and the thickness of the first terrace-shaped protrusion microstructure is the same as the thickness of the second terrace-shaped protrusion microstructure.

3. The resistive random access memory according to claim 2, characterized in that: The resistive material layer includes a plurality of resistive units; The number of the resistive switching units, the number of the first terrace-shaped protruding microstructures and the number of the second terrace-shaped protruding microstructures are the same and are arranged in one-to-one correspondence, and the orthographic projection of the resistive switching unit on the first surface, the orthographic projection of the first terrace-shaped protruding microstructure on the first surface and the orthographic projection of the second terrace-shaped protruding microstructure on the first surface overlap; In the first direction, at least two of the resistive switching units have different thicknesses.

4. The resistive random access memory according to claim 1, wherein: In the first direction, at least two of the first terrace-shaped protrusion microstructures have different thicknesses, at least two of the second terrace-shaped protrusion microstructures have different thicknesses, and the thickness of the first terrace-shaped protrusion microstructure and the thickness of the second terrace-shaped protrusion microstructure overlapped in one-to-one correspondence are the same.

5. The resistive random access memory according to claim 4, characterized in that: Along the second direction, the thickness of each of the first terrace-shaped protruding microstructures decreases sequentially, and the thickness of each of the second terrace-shaped protruding microstructures decreases sequentially; wherein the second direction is perpendicular to the thickness direction of the resistive material layer.

6. The resistive random access memory according to claim 1, characterized in that: The first electrode includes a plurality of first sub-electrodes; The number of the first sub-electrodes is the same as the number of the first terrace-shaped protruding microstructures and they are arranged in one-to-one correspondence, and the orthographic projection of the first sub-electrodes on the first surface overlaps with the orthographic projection of the first terrace-shaped protruding microstructures on the first surface; The first terrace-shaped protruding microstructures are located on a side surface of the first sub-electrode in a one-to-one correspondence.

7. The resistive random access memory according to claim 1, characterized in that: On one side surface of the first electrode, each of the first terrace-shaped protruding microstructures is arranged in an array; The second terrace-shaped protruding microstructures are arranged in an array on one side surface of the second electrode.

8. The resistive random access memory according to claim 1, wherein: Also included is an argon ion implanted isolation layer; The argon ion implantation isolation layer is located between adjacent first terrace-shaped protruding microstructures, and / or the argon ion implantation isolation layer is located between adjacent second terrace-shaped protruding microstructures.

9. The resistive random access memory according to claim 1, wherein: In the first direction, the thickness of the resistive material layer is in a range of 5 nm to 200 nm.

10. The resistive random access memory according to claim 1, wherein: In the first direction, the thickness of the first terrace-shaped protruding microstructure is in a range of 1 nm to 5 nm, and the thickness of the second terrace-shaped protruding microstructure is in a range of 1 nm to 5 nm.

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