Preparation and processing method of memristor based on AlScN ferroelectric material

Abstract

The invention discloses a preparation and processing method of a memristor based on an AlScN ferroelectric material, and the preparation method comprises the steps: depositing an AlScN thin film on a patterned Pt electrode through a magnetron sputtering method, enabling a patterned Cu electrode to cover the AlScN thin film, obtaining a volatile memristor based on the AlScN ferroelectric material, carrying out the thermal annealing treatment in a nitrogen atmosphere, and obtaining the memristor based on the AlScN ferroelectric material. And processing to obtain the nonvolatile memory resistor device based on the AlScN ferroelectric material. The volt-ampere characteristic of the annealed memristor based on the AlScN ferroelectric material is converted from the volatility to the non-volatility compared with the volt-ampere characteristic of the memristor based on the AlScN ferroelectric material before annealing; the preparation method and the treatment method are simple in process operation and have a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor materials and devices, and in particular relates to a preparation and processing method of a memristor device based on AlScN ferroelectric material. Background Art

[0002] Ferroelectric materials are a class of functional materials with spontaneous polarization characteristics, and their polarization direction can change reversibly under the action of an external electric field. This unique property makes ferroelectric materials have broad application prospects in the fields of memory, sensors, actuators, energy storage and conversion. In addition, the dielectric, piezoelectric and pyroelectric properties of ferroelectric materials further broaden their potential uses in microelectronic devices, biomedical equipment and green energy development. With the rapid development of micro-nanotechnology, the research on ferroelectric materials has gradually expanded from traditional inorganic materials (such as niobates, titanates, etc.) to new composite materials and two-dimensional materials. These new ferroelectric materials not only have better performance, but also can achieve multifunctional integration on a smaller scale to meet the needs of the next generation of high-performance devices. However, the existing technology still has many challenges in improving ferroelectric performance, optimizing environmental stability and simplifying manufacturing processes. Therefore, exploring the preparation of ferroelectric materials with high stability, high performance and low cost, as well as developing new applications in cutting-edge technologies, has become the focus and difficulty of current research.

[0003] Compared with traditional ferroelectric materials (such as barium strontium titanate and lead zirconate titanate), AlScN materials not only have higher Curie temperatures and wider operating temperature ranges, but also can achieve significant ferroelectric properties at a thinner thickness, which is of great significance for the high-density integration of microelectronics and power devices. In addition, the chemical and mechanical stability of AlScN makes it possible to be used in harsh environments, such as aerospace, automotive electronics, and industrial sensing. However, there are still technical bottlenecks in the optimization of doping concentration of AlScN materials, control of film deposition processes, and long-term stability of ferroelectric properties. Due to the simple growth process and low growth temperature of magnetron sputtering, many AlScN films are currently grown by magnetron sputtering. However, the quality of films grown by magnetron sputtering is not very ideal, which affects the preparation and application of devices. Summary of the invention

[0004] To solve the above problems, the present invention proposes a preparation and processing method of a memristor device based on AlScN ferroelectric material. In the preparation method, an AlScN film is deposited on a patterned Pt electrode by a magnetron sputtering method, and a patterned Cu electrode is covered on the AlScN film to prepare a volatile memristor device based on AlScN ferroelectric material, and a thermal annealing treatment is performed in a nitrogen atmosphere to obtain a non-volatile memristor device based on AlScN ferroelectric material; the volt-ampere characteristic of the annealed AlScN ferroelectric material memristor device is changed from volatile to non-volatile compared with that before annealing; the preparation method and the processing method are simple in operation and have good application prospects.

[0005] The present invention adopts the following technical solutions:

[0006] A method for preparing a memristor device based on AlScN ferroelectric material comprises the following steps:

[0007] S1, depositing high-purity Pt on a clean silicon substrate to form a Pt film, and using the patterned Pt film as a lower electrode;

[0008] S2, on the patterned Pt film, Al 0.73 Sc 0.27 AlScN film is deposited by N alloy target;

[0009] S3. On the surface of the deposited AlScN film, a copper film is deposited by physical vapor deposition, and the patterned copper film is used as an upper electrode; a complete AlScN ferroelectric material memristor device is formed by a silicon substrate, a Pt film, an AlScN film and a copper film.

[0010] Preferably, the thickness of the Pt film in step S1 is 100 nm, and the Pt film is patterned to a size of 300 μm in length and width by photolithography technology.

[0011] Preferably, the thickness of the AlScN film in step S2 is 30 nm; the sputtering power of the AlScN film is 100 W, the working gas is nitrogen, the gas flow rate is 10 sccm, and the chamber pressure is maintained at 1 mTorr during deposition.

[0012] Preferably, the copper film in step S3 has a thickness of 100 nm, and the copper film is patterned by photolithography technology to a size of 300 μm in length and width.

[0013] Preferably, in step S3, the Pt film is composed of a plurality of spaced Pt strips, the AlScN film is composed of a plurality of AlScN columns, and the copper film is composed of a plurality of copper strips perpendicular to the Pt strips; and both ends of the AlScN columns are fixedly connected to the Pt strips and the copper strips, respectively.

[0014] A volatile memristor device based on AlScN ferroelectric material is prepared by adopting the preparation method of the memristor device based on AlScN ferroelectric material.

[0015] A processing method for a memristor device based on AlScN ferroelectric material, wherein the memristor device based on AlScN ferroelectric material prepared by the preparation method of the memristor device based on AlScN ferroelectric material is annealed in a nitrogen atmosphere, wherein the specific process of the annealing treatment is as follows: the memristor device based on AlScN ferroelectric material is placed in a tubular annealing furnace, and in a nitrogen atmosphere, the ambient temperature of the annealing furnace is gradually increased to 350°C, and the temperature is maintained at 350°C for 1 hour for annealing treatment; after annealing, the device is naturally cooled to room temperature.

[0016] A nonvolatile AlScN ferroelectric material-based memristor device is prepared by using the AlScN ferroelectric material-based memristor processing method.

[0017] After adopting the above technical scheme, the present invention has the following advantages compared with the background technology: the preparation method of the present invention deposits an AlScN film on a patterned Pt electrode by a magnetron sputtering method, and covers the patterned Cu electrode on the AlScN film to prepare a volatile AlScN ferroelectric material-based memristor device, and performs thermal annealing treatment in a nitrogen atmosphere to obtain a non-volatile AlScN ferroelectric material-based memristor device; the volt-ampere characteristics of the annealed AlScN ferroelectric material-based memristor device are changed from volatile to non-volatile compared with before annealing; the preparation method and the treatment method are simple to operate and have good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the memristor device based on AlScN ferroelectric material of the present invention;

[0019] Figure 2 This is a graph showing the volt-ampere characteristic of a volatile AlScN ferroelectric material memristor device that has not been annealed in Example 1 of the present invention;

[0020] Figure 3 This is a graph showing the volt-ampere characteristic of the nonvolatile AlScN ferroelectric material memristor device after annealing in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] See also Figures 1 to 3 .

[0023] Example 1

[0024] A method for preparing a memristor device based on AlScN ferroelectric material comprises the following steps:

[0025] S1, depositing high-purity Pt on a clean silicon substrate to form a Pt film, and using the patterned Pt film as a lower electrode;

[0026] The thickness of the Pt film in step S1 is 100 nm, and the Pt film is patterned to a size of 300 μm in length and width by photolithography technology;

[0027] S2, on the patterned Pt film, Al 0.73 Sc 0.27 AlScN film is deposited by N alloy target;

[0028] The thickness of the AlScN film in step S2 is 30 nm; the sputtering power of the AlScN film is 100 W, the working gas is nitrogen, the gas flow rate is 10 sccm, and the chamber pressure is maintained at 1 mTorr during deposition;

[0029] S3, depositing a copper film on the surface of the deposited AlScN film by physical vapor deposition, and using the patterned copper film as an upper electrode; forming a complete AlScN ferroelectric material memristor device by the silicon substrate, the Pt film, the AlScN film and the copper film;

[0030] In step S3, the copper film has a thickness of 100 nm, and the copper film is patterned by photolithography to a size of 300 μm in length and width;

[0031] In step S3, the Pt film is composed of a plurality of Pt strips arranged at intervals, the AlScN film is composed of a plurality of AlScN columns, and the copper film is composed of a plurality of copper strips perpendicular to the Pt strips; the two ends of the AlScN column are fixedly connected to the Pt strip and the copper strip, respectively. Figure 1 shown.

[0032] The AlScN ferroelectric material memristor device without annealing in this embodiment 1 is a volatile AlScN ferroelectric material memristor device, showing volatility. The volt-ampere characteristic curve of the volatile AlScN ferroelectric material memristor device is as follows: Figure 2 shown.

[0033] Example 2

[0034] A processing method for a memristor device based on AlScN ferroelectric material, the memristor device based on AlScN ferroelectric material prepared in Example 1 is annealed in a nitrogen atmosphere, the specific process of the annealing treatment is: placing the memristor device based on AlScN ferroelectric material in a tubular annealing furnace, in a nitrogen atmosphere, gradually increasing the ambient temperature of the annealing furnace to 350°C, and maintaining the temperature at 350°C for 1 hour for annealing; after annealing, naturally cooling to room temperature.

[0035] The AlScN ferroelectric material memristor device after annealing in this embodiment 2 is a non-volatile AlScN ferroelectric material memristor device and also exhibits non-volatility. The volt-ampere characteristic curve of the non-volatile AlScN ferroelectric material memristor device is as follows: Figure 3 shown.

[0036] See also Figure 2 and Figure 3 Before annealing, the AlScN ferroelectric material memristor device exhibits volatility. After annealing, the device can achieve coexistence of volatility and non-volatility by changing the current limit.

[0037] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing a memristor device based on AlScN ferroelectric material, characterized in that: The following steps are involved: S1, depositing high-purity Pt on a clean silicon substrate to form a Pt film, and using the patterned Pt film as a lower electrode; S2, on the patterned Pt film, Al 0.73 Sc 0.27 AlScN film is deposited by N alloy target; S3. On the surface of the deposited AlScN film, a copper film is deposited by physical vapor deposition, and the patterned copper film is used as an upper electrode; a complete AlScN ferroelectric material memristor device is formed by a silicon substrate, a Pt film, an AlScN film and a copper film.

2. The method for preparing and processing a memristor device based on AlScN ferroelectric material according to claim 1, characterized in that: The thickness of the Pt film in step S1 is 100 nm, and the Pt film is patterned to a size of 300 μm in length and width by photolithography technology.

3. The method for preparing and processing a memristor device based on AlScN ferroelectric material according to claim 1, characterized in that: The thickness of the AlScN film in step S2 is 30 nm; the sputtering power of the AlScN film is 100 W, the working gas is nitrogen, the gas flow rate is 10 sccm, and the chamber pressure is maintained at 1 mTorr during deposition.

4. The method for preparing and processing a memristor device based on AlScN ferroelectric material according to claim 1, characterized in that: The thickness of the copper film in step S3 is 100 nm, and the copper film is patterned to a size of 300 μm in length and width by photolithography technology.

5. The method for preparing and processing a memristor device based on AlScN ferroelectric material according to claim 1, characterized in that: In step S3, the Pt film is composed of a plurality of Pt strips arranged at intervals, the AlScN film is composed of a plurality of AlScN columns, and the copper film is composed of a plurality of copper strips perpendicular to the Pt strips; the two ends of the AlScN column are fixedly connected to the Pt strip and the copper strip respectively.

6. A volatile AlScN ferroelectric material memristor device, characterized in that: The volatile AlScN ferroelectric material-based memristor device is prepared by using the preparation method of the AlScN ferroelectric material-based memristor device according to any one of claims 1 to 5.

7. A processing method for a memristor device based on AlScN ferroelectric material, characterized in that: The AlScN ferroelectric material memristor device prepared by the preparation method of the AlScN ferroelectric material memristor device as described in any one of claims 1 to 5 is annealed in a nitrogen atmosphere. The specific process of the annealing treatment is: placing the AlScN ferroelectric material memristor device in a tubular annealing furnace, gradually increasing the ambient temperature of the annealing furnace to 350°C in a nitrogen atmosphere, and maintaining the annealing treatment at 350°C for 1 hour; after annealing, naturally cooling to room temperature.

8. A non-volatile AlScN ferroelectric material memristor device, characterized in that: The nonvolatile AlScN ferroelectric material-based memristor device is prepared by using the processing method of the AlScN ferroelectric material-based memristor device according to claim 7.

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