A strontium titanate-based oxide superlattice thin film memristor and its preparation method

Abstract

The present invention provides a strontium titanate-based oxide superlattice thin film memristor and a preparation method thereof. The preparation method comprises the following steps: using a niobium-doped strontium titanate single crystal substrate as a bottom electrode; alternately depositing strontium titanate layers and another type of oxide film layer on the surface of the niobium-doped strontium titanate single crystal substrate to prepare a strontium titanate-based oxide superlattice thin film as a storage dielectric layer, wherein the other type of oxide film layer is selected from one of yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite; and further depositing a metal film as a top electrode on the surface of the substrate coated with the storage dielectric layer obtained in step S2, to obtain a memristor comprising bottom electrode||STO-based oxide superlattice thin film storage dielectric layer||top electrode. The strontium titanate-based oxide superlattice thin film memristor prepared by this preparation method can form a single crystal or a superlattice thin film with high crystal integrity, and the memristor has a low operating voltage and high configuration stability.

Description

Technical Field

[0001] The present invention relates to the technical field of microelectronic devices, and in particular to a strontium titanate-based oxide superlattice thin film memristor and a preparation method thereof. Background Art

[0002] A memristor is a nonlinear resistor element with memory function. It mainly uses the phenomenon that certain thin film materials will transition between different resistance states (high and low resistance states) under the action of electrical stimulation to store data. It has many advantages such as non-volatile memory, high speed and low power consumption, integrated storage and computing, and easy high integration. It has huge application prospects in modern information storage, brain-like artificial intelligence, and implantable bioelectronic devices. It is also an important technical route choice to break through the bottleneck of traditional von Neumann computer architecture.

[0003] Typically, the basic unit of a memristor is a "sandwich" structure consisting of upper and lower electrodes and a resistive switching layer material with memristive properties in between. The development of resistive switching layer materials is one of the keys to achieving high-performance memristors. Currently, a wide variety of resistive switching layer materials are available for memristor fabrication. Among them, binary or multi-component metal oxides are commonly used as resistive switching layer materials for memristor fabrication. Compared to other material systems such as sulfides and organic compounds, metal oxides have been used the earliest and are relatively more mature as resistive switching active layer materials. However, further improving their performance is key to expanding the application of these materials.

[0004] Selecting two active layer materials and periodically alternating deposition to create nanostructured multilayer or superlattice films, and then manipulating carrier mobility within them, is a novel structural design and performance control method for improving the performance of memristor resistive switching layer materials. Unfortunately, there are currently no reports on superlattice thin-film memristors. Successful applications of ZrO2 (8% Y2O3, abbreviated as YSZ) and typical perovskite oxides (such as SrTiO3, LaCoO3, or BiFeO3) as active layer materials have been reported in memristors. Using superlattice or nanostructured multilayer structures is expected to significantly improve the mobility of oxygen ions, which act as charge carriers, thereby enhancing the electric field sensitivity and efficiency of memristor active layer materials. Therefore, the design and preparation of STO-based superlattice films as resistive switching active layer materials, using STO and YSZ (or perovskite oxides such as LCO and BFO) as component materials, is of great significance for the development of novel memristors.

[0005] Published patent CN 111009609 A also proposes using two oxides to form a superlattice thin film as the resistive switching layer of a memristor. However, this patent uses a single-crystal silicon substrate. A 20-200nm thick layer of nitride, such as TiN, TaN, or one of the metals Pt, Au, Pd, or Ir, is then deposited on this surface via physical vapor deposition (preferably magnetron sputtering) as a bottom electrode. Two binary metal oxides (Hf, Al, Ti, Ta, Cu, W, Ni, Zn, Zr, Fe, Mn, or Nb) are then alternately deposited on top to form the superlattice film. Because the crystal structure and lattice parameters of this type of superlattice film differ significantly from those of the oxide film deposited on it, the resulting superlattice film is often amorphous.

[0006] The object of the present invention is to provide a process for preparing a memristor having a single crystal or a superlattice thin film with high crystal integrity. Summary of the Invention

[0007] The object of the present invention is to provide a method for preparing a strontium titanate-based oxide superlattice thin film memristor, which can form a single crystal or a superlattice thin film with high crystal integrity. The memristor has low operating voltage and high configuration stability.

[0008] In order to solve the above problems, the technical solutions of the present invention are as follows:

[0009] A method for preparing a strontium titanate-based oxide superlattice thin film memristor comprises the following steps:

[0010] Step S1, using a strontium niobate-doped single crystal substrate as a bottom electrode;

[0011] Step S2, alternately depositing strontium titanate layers and another type of oxide film layers on the surface of the niobium-doped strontium titanate single crystal substrate to prepare a strontium titanate-based oxide superlattice thin film as a storage medium layer, wherein the other type of oxide film layer is selected from one of yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite;

[0012] Step S3, depositing a metal film as a top electrode on the surface of the substrate coated with the storage dielectric layer obtained in step S2, to obtain a memristor containing bottom electrode|STO-based oxide superlattice thin film storage dielectric layer|top electrode.

[0013] Furthermore, in step S1, the niobium doping concentration of the strontium titanate single crystal substrate material is 0.01-1.0 wt%, and the crystal orientation is (100), (110) or (111).

[0014] Furthermore, in step S2, pulsed laser deposition technology is used to alternately bombard the strontium titanate target material and another type of oxide target material with high-energy-density laser to obtain a strontium titanate-based oxide superlattice film in which strontium titanate layers and another type of oxide layers grow alternately; wherein, within each modulation period of the superlattice film, the strontium titanate layer is always grown first, and then the other oxide layer is grown.

[0015] Furthermore, the thickness of the strontium titanate layer is 2-20 nm, the thickness of the other type of oxide layer is 0.5-10 nm, and the total thickness of the superlattice film is 20-100 nm.

[0016] Furthermore, in step S2, the yttrium-doped zirconia material selected for the other type of oxide film layer has a molar doping amount of Y2O3 of 6-10%.

[0017] Furthermore, in step S3, the top electrode is an inert metal thin film electrode or an active metal thin film electrode, wherein the inert metal is Pt or Au, and the active metal is Ag, Al or Cu.

[0018] Furthermore, the top electrode is formed by magnetron sputtering or vacuum evaporation, and its thickness is ≥50nm.

[0019] The present invention also provides a strontium titanate-based oxide superlattice thin film memristor, comprising a bottom electrode, a storage dielectric layer deposited on the surface of the bottom electrode, and a top electrode deposited on the surface of the storage dielectric layer. The bottom electrode is a niobium-doped strontium titanate single crystal substrate, the storage dielectric layer comprises alternately deposited strontium titanate layers and another type of oxide film layer, the strontium titanate layer is deposited on the surface of the bottom electrode, and the other type of oxide film layer is selected from one of yttrium-doped zirconium oxide, lanthanum cobaltate, or bismuth ferrite.

[0020] Furthermore, the thickness of the strontium titanate layer is 2-20 nm, the thickness of the other type of oxide layer is 0.5-10 nm, and the total thickness of the storage medium layer is 20-100 nm.

[0021] Furthermore, in the yttrium-doped zirconia material selected for another type of oxide film layer, the molar doping amount of Y2O3 is 6-10%.

[0022] Compared with the prior art, the strontium titanate-based oxide superlattice thin film memristor and its preparation method provided by the present invention have the following beneficial effects:

[0023] 1. The preparation method of the strontium titanate-based oxide superlattice thin film memristor provided by the present invention uses single-crystalline Nb-doped SrTiO3 as a substrate. This material can serve as both a bottom electrode and a template for crystal growth. By epitaxially growing a SrTiO3 thin film on it, the initially grown SrTiO3 thin film is controlled to have a single crystal structure. Then, by utilizing its crystal template effect, a coherent interface structure is formed between yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite, etc., which are confined to a certain thickness, and the SrTiO3, thereby forming a single crystal or a superlattice film with high crystal integrity. A top electrode is then prepared on the superlattice film to construct a strontium titanate-based oxide superlattice thin film memristor. The memristor prepared by the present invention has a low operating voltage and high resistance state stability. For example, after undergoing 1000 pulse switching tests, its high and low resistance states can still remain stable, and the resistance state remains stable for more than 5×10 3 s, the operating voltage of the device is ≤2V. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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.

[0025] Figure 1 Schematic diagram of the structure of the STO-based oxide superlattice thin film memristor prepared by the present invention;

[0026] Figure 2 is a TEM image of the TO / YSZ superlattice film prepared in Example 1;

[0027] Figure 3 1 is a comparison chart of the electrical conductivity of the STO / YSZ superlattice film prepared in Example 1 and the STO and YSZ single-layer films;

[0028] Figure 4 1 is the IV test curve of the STO / YSZ superlattice thin film memristor prepared in Example 1 and the corresponding STO single-layer thin film memristor and YSZ single-layer thin film memristor;

[0029] Figure 5 The STO / YSZ superlattice thin film memristor prepared in Example 1 was subjected to a cyclic test (1000 times);

[0030] Figure 6 is the resistance state retention time of the STO / YSZ superlattice thin film memristor prepared in Example 1;

[0031] Figure 7 is the IV test curve of the STO / LCO superlattice film prepared in Example 2;

[0032] Figure 8 This is the IV test curve of the STO / BFO superlattice film prepared in Example 3. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific implementation methods of the present invention are further described below.

[0034] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0035] A method for preparing a strontium titanate-based oxide superlattice thin film memristor comprises the following steps:

[0036] Step S1, using a strontium niobate-doped single crystal substrate as a bottom electrode;

[0037] Specifically, the niobium-doped strontium titanate (Nb:SrTiO3, abbreviated as NSTO) single crystal substrate material has a niobium doping mass concentration of 0.01 to 1.0 wt%, and its crystal orientation is (100), (110) or (111), wherein the niobium doping mass concentration can be 0.01%, 0.05%, 0.08%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9% or 1.0%, or other concentration values ​​within this range.

[0038] Step S2, alternately depositing strontium titanate (SrTiO3, abbreviated as STO) layers and another type of oxide film layer on the surface of the niobium-doped strontium titanate single crystal substrate to prepare an STO-based oxide superlattice thin film as a storage medium layer, wherein the other type of oxide film layer is selected from yttrium-doped zirconium oxide (YSZ), lanthanum cobalt oxide (LaCoO3, abbreviated as LCO), or bismuth ferrite (BiFeO3, abbreviated as BFO);

[0039] In the yttrium-doped zirconia material, the molar doping amount of Y2O3 is 6-10%, such as 6%, 7%, 8%, 9%, or 10%, or other values ​​within the range.

[0040] Specifically, the deposition process uses pulsed laser deposition technology to alternately bombard the STO target and another type of oxide target with high-energy-density laser light, resulting in an STO-based oxide superlattice film with alternating STO layers and another type of oxide layer. Within each superlattice film modulation cycle, the STO layer grows first, followed by the other oxide layer. The resulting STO layer has a thickness of 2 to 20 nm, while the other oxide layer has a thickness of 0.5 to 10 nm, resulting in a total superlattice film thickness of 20 to 100 nm.

[0041] Step S3, depositing a metal film as a top electrode on the surface of the substrate coated with the storage dielectric layer obtained in step S2, to obtain a memristor containing bottom electrode|STO-based oxide superlattice thin film storage dielectric layer|top electrode.

[0042] Specifically, the top electrode is an inert metal thin film electrode or an active metal thin film electrode, wherein the inert metal is Pt or Au, and the active metal is Ag, Al, or Cu. The top electrode is formed by magnetron sputtering or vacuum evaporation, and its thickness is ≥50nm.

[0043] See also Figure 1 , is a schematic diagram of the structure of an STO-based oxide superlattice thin-film memristor prepared by the present invention. The strontium titanate-based oxide superlattice thin-film memristor prepared using the above method comprises a bottom electrode 1, a storage dielectric layer 2 deposited on the surface of the bottom electrode 1, and a top electrode 3 deposited on the surface of the storage dielectric layer 2. The bottom electrode 1 is a niobium-doped strontium titanate single crystal substrate, and the storage dielectric layer 2 comprises alternating deposits of strontium titanate layers 21 and another type of oxide film layer 22. The strontium titanate layers 21 are deposited on the surface of the bottom electrode 1, and the other type of oxide film layer 22 is selected from one of yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite.

[0044] The thickness of the strontium titanate layer 21 is 2-20 nm, the thickness of the other type of oxide layer 22 is 0.5-10 nm, and the total thickness of the storage medium layer 2 is 20-100 nm.

[0045] The strontium titanate-based oxide superlattice thin film memristor and its preparation method provided by the present invention are described in detail below through specific examples.

[0046] Example 1

[0047] An STO-based oxide superlattice thin film memristor, such as Figure 1 The structure comprises, from bottom to top, a strontium titanate single crystal substrate doped with niobium, an STO / YSZ superlattice storage dielectric film, and a Pt top electrode. The preparation method is as follows:

[0048] Step S1: a commercially available (001) oriented niobium-doped strontium titanate single crystal substrate (NSTO, 0.7 wt% Nb) is ultrasonically cleaned with alcohol and acetone, and then placed in an oven for drying. The substrate is then heated in an oven for 30 minutes and dried for later use.

[0049] Step S2: Using a laser pulse deposition technique, a STO target (99.99% purity) and a YSZ target (8 mol% Y, 99.99% purity) were alternately bombarded on an NSTO substrate with a high-energy-density laser to obtain an STO / YSZ superlattice thin film in which STO and YSZ layers were alternately grown. In each growth modulation cycle, the STO layer was always grown first, followed by the YSZ layer, and the number of modulation cycles was 5. The substrate temperature was 750°C, the STO single layer deposition time was 115 s, the YSZ single layer deposition time was 108 s, and the chamber vacuum was 4.95×10 -4 Pa, the oxygen pressure during film deposition was 2.50×10 -2 Pa, and the laser energy was 200 mJ (constant energy).

[0050] Step S3: Using magnetron sputtering equipment, a metal Pt film is deposited on the thin film obtained in step S2 as a top electrode with a thickness of about 80 nm. The basic process parameters are: wait until the vacuum degree of the chamber is evacuated to 5×10 -3 After Pa, Ar gas with a purity of 99.999% was introduced, and the pressure was maintained at 0.6 Pa. Then, the power of the Pt target (purity of 99.99%) was turned on, the target power was 800 W, and the deposition time was 5 minutes.

[0051] Please refer to Figures 2 to 6 ,in Figure 2 is a TEM image of the TO / YSZ superlattice film prepared in Example 1; Figure 3 1 is a comparison chart of the electrical conductivity of the STO / YSZ superlattice film prepared in Example 1 and the STO and YSZ single-layer films; Figure 4 1 is the IV test curve of the STO / YSZ superlattice thin film memristor prepared in Example 1 and the corresponding STO single-layer thin film memristor and YSZ single-layer thin film memristor; Figure 5 The STO / YSZ superlattice thin film memristor prepared in Example 1 was subjected to a cyclic test (1000 times); Figure 6 is the resistance state retention time of the STO / YSZ superlattice thin film memristor prepared in Example 1.

[0052] Depend on Figure 2 It can be seen that the total thickness of the STO / YSZ superlattice film of this embodiment is about 20nm, wherein the thickness of STO and YSZ in each growth cycle is 2nm; Figure 3It can be seen that compared with the single-layer STO film and YSZ film, the conductivity of the STO (2nm) / YSZ (2nm) superlattice film can be significantly improved, from 10 of the corresponding single-layer film to 2 ~10 3 S / cm increased to 10 7 S / cm; Figure 4 It can be seen that the IV curves of the memristor devices constructed with single-layer STO film and YSZ film respectively do not show memristive characteristics, but show capacitive characteristics due to their low conductivity. However, the IV test curve of the memristor constructed with STO (2nm) / YSZ (2nm) superlattice film shows obvious memristive characteristics. Figures 5 and 6 It can be seen that the high and low resistance states of the STO (2nm) / YSZ (2nm) superlattice thin film memristor in this embodiment can still remain stable after 1000 cycles of testing ( Figure 5 ), the resistance state remains stable for more than 5×10 3 s( Figure 6 ), with good stability.

[0053] Example 2

[0054] An STO-based oxide superlattice thin film memristor, such as Figure 1 As shown, its structure from bottom to top includes: strontium niobate-doped titanate substrate, STO / LCO superlattice storage dielectric film, and Au top electrode. Its preparation method is as follows:

[0055] Step S1: a commercially available (111) oriented niobium-doped strontium titanate substrate (NSTO, 0.5 wt% Nb) is ultrasonically cleaned with alcohol and acetone, and then placed in an oven for drying. The substrate is then heated in an oven for 30 minutes and dried for later use.

[0056] Step S2: Using laser pulse deposition technology, a STO target (purity 99.99%) and an LCO target (purity 99.99%) were alternately bombarded on an NSTO substrate with a high energy density laser to obtain an STO / LCO superlattice thin film with alternating STO and LCO layers. In each growth modulation cycle, the STO layer was always grown first, followed by the LCO layer, and the number of modulation cycles was 10. The substrate temperature was 800°C, the STO single layer deposition time was 300 seconds, the LCO single layer deposition time was 120 seconds, and the chamber vacuum was 5.75×10 -4 Pa, the oxygen pressure during film deposition was 2.50×10 -2 Pa, and the laser energy was 200 mJ (constant energy).

[0057] Step S3: Using magnetron sputtering equipment, a metal Au film is deposited as a top electrode on the STO / LCO superlattice film obtained in step S2. The film thickness is about 80 nm. The basic process parameters are: wait until the vacuum degree of the chamber is 5×10 -3 After Pa, Ar gas with a purity of 99.999% was introduced, and the pressure was maintained at 0.5 Pa. Then, the power of the Au target (purity of 99.99%) was turned on, the target power was 700 W, and the deposition time was 5 minutes.

[0058] Please refer to Figure 7 , is the IV test curve of the STO / LCO superlattice film prepared in Example 2, Figure 7 It can be seen that the device has obvious memristive characteristics.

[0059] Example 3

[0060] An STO-based oxide superlattice thin film memristor, such as Figure 1 As shown in the figure, its structure, from bottom to top, includes: a strontium niobate-doped single crystal substrate, an STO / BFO superlattice thin film storage dielectric film, and an Al top electrode. Its preparation method is as follows:

[0061] Step S1: a commercially available (110) oriented niobium-doped strontium titanate substrate (NSTO, 0.05 wt%) was ultrasonically cleaned with alcohol and acetone, and then placed in an oven for drying. The substrate was then heated in an oven for 40 minutes and dried for later use.

[0062] Step S2: STO / BFO superlattice thin films are sequentially deposited on the substrate by laser pulse deposition technology. The substrate temperature is 750°C when depositing STO, 500°C when depositing BFO, the STO single layer deposition time is 300s, the BFO deposition time is 100s, and the vacuum degree is 2.88×10 -4 Pa, the pressure after oxygen is introduced is 3.34×10 -2 Pa, and the laser energy was 200 mJ (constant energy).

[0063] Step S3: Using magnetron sputtering equipment, a metal Al film is deposited as a top electrode on the STO / BFO superlattice oxide film obtained in step S2. The film thickness is about 50 nm. The basic process parameters are: wait until the vacuum degree of the chamber is evacuated to 5×10 -3 After Pa, Ar gas with a purity of 99.999% was introduced, and the pressure was maintained at 0.6 Pa. Then, the power of the Al target (purity of 99.9%) was turned on, the target power was 800 W, and the deposition time was 3 minutes.

[0064] Please refer to Figure 8 , is the IV test curve of the STO / BFO superlattice film prepared in Example 3, Figure 8It can be seen that the device has obvious memristive characteristics.

[0065] Compared with the prior art, the strontium titanate-based oxide superlattice thin film memristor and its preparation method provided by the present invention have the following beneficial effects:

[0066] 1. The preparation method of the strontium titanate-based oxide superlattice thin film memristor provided by the present invention uses single-crystalline Nb-doped SrTiO3 as a substrate. This material can serve as both a bottom electrode and a template for crystal growth. By epitaxially growing a SrTiO3 thin film on it, the initially grown SrTiO3 thin film is controlled to have a single crystal structure. Then, by utilizing its crystal template effect, a coherent interface structure is formed between yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite, etc., which are confined to a certain thickness, and the SrTiO3, thereby forming a single crystal or a superlattice film with high crystal integrity. A top electrode is then prepared on the superlattice film to construct a strontium titanate-based oxide superlattice thin film memristor. The memristor prepared by the present invention has a low operating voltage and high resistance state stability. For example, after undergoing 1000 pulse switching tests, its high and low resistance states can still remain stable, and the resistance state remains stable for more than 5×10 3 s, the operating voltage of the device is ≤2V.

[0067] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. It is apparent to those skilled in the art that various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for preparing a strontium titanate-based oxide superlattice thin film memristor, characterized in that: The steps include: Step S1, using a strontium niobate-doped single crystal substrate as a bottom electrode; Step S2, alternately depositing strontium titanate layers and another type of oxide film layers on the surface of the niobium-doped strontium titanate single crystal substrate to prepare a strontium titanate-based oxide superlattice thin film as a storage medium layer, wherein the other type of oxide film layer is selected from one of yttrium-doped zirconium oxide, lanthanum cobalt oxide, or bismuth ferrite; Specifically, a pulsed laser deposition technique is used to alternately bombard a strontium titanate target and another type of oxide target with a high-energy-density laser to obtain a strontium titanate-based oxide superlattice film in which strontium titanate layers and another type of oxide layers are alternately grown. Within each modulation cycle of the superlattice film, the strontium titanate layer is always grown first, followed by the other type of oxide layer, and the number of modulation cycles is 5-10. The thickness of the strontium titanate layer is 2-20 nm, the thickness of the other type of oxide layer is 0.5-10 nm, and the total thickness of the superlattice film is 20-100 nm. Step S3, depositing a metal film as a top electrode on the surface of the substrate coated with the storage dielectric layer obtained in step S2, to obtain a memristor containing bottom electrode|STO-based oxide superlattice thin film storage dielectric layer|top electrode.

2. The method for preparing a strontium titanate-based oxide superlattice thin film memristor according to claim 1, wherein: In step S1, the niobium doping concentration of the niobium-doped strontium titanate single crystal substrate material is 0.01-1.0 wt %, and the crystal orientation thereof is (100), (110) or (111).

3. The method for preparing a strontium titanate-based oxide superlattice thin film memristor according to claim 1, wherein: In step S2, the yttrium-doped zirconia material selected for the other type of oxide film layer has a molar doping amount of Y2O3 of 6-10%.

4. The method for preparing a strontium titanate-based oxide superlattice thin film memristor according to claim 1, wherein: In step S3 , the top electrode is an inert metal thin film electrode or an active metal thin film electrode, wherein the inert metal is Pt or Au, and the active metal is Ag, Al or Cu.

5. The method for preparing a strontium titanate-based oxide superlattice thin film memristor according to claim 4, characterized in that: The top electrode is formed by magnetron sputtering or vacuum evaporation, and its thickness is ≥50nm.

6. A strontium titanate-based oxide superlattice thin film memristor comprising a bottom electrode, a storage dielectric layer deposited on a surface of the bottom electrode, and a top electrode deposited on a surface of the storage dielectric layer, characterized in that: The bottom electrode is a niobium-doped strontium titanate single crystal substrate, and the storage medium layer includes alternately deposited strontium titanate layers and another type of oxide film layer, wherein the strontium titanate layer is deposited on the surface of the bottom electrode, and the other type of oxide film layer is selected from one of yttrium-doped zirconium oxide, lanthanum cobaltate, or bismuth ferrite; The storage medium layer adopts pulsed laser deposition technology, and the strontium titanate target material and another type of oxide target material used are alternately bombarded by high-energy-density laser to obtain a strontium titanate-based oxide superlattice film in which the strontium titanate layer and the other type of oxide layer grow alternately. In each modulation cycle of the superlattice film, the strontium titanate layer is always grown first, and then the other oxide layer is grown, and the number of modulation cycles is 5-10; the layer thickness of the strontium titanate layer is 2-20nm, the layer thickness of the other type of oxide layer is 0.5-10nm, and the total thickness of the superlattice film is 20-100nm.

7. The strontium titanate-based oxide superlattice thin film memristor according to claim 6, characterized in that: In the yttrium-doped zirconia material selected for another type of oxide film layer, the molar doping amount of Y2O3 is 6-10%.

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