Halogen hybrid perovskite-based self-rectifying memristor and preparation method thereof

Abstract

The application discloses a self-rectifying memristor based on halogen hybrid perovskite, and belongs to the technical field of microelectronic manufacturing and storage. The self-rectifying memristor is a three-layer device comprising an upper electrode, a perovskite layer and a lower electrode, and presents high and low resistance states in a negative voltage scanning range, and always keeps in a high resistance state in a positive voltage scanning range. The memristor relies on a metal halide instantaneously formed at a perovskite / metal interface, and the perovskite can form a p-n junction with the halide, a reverse p-n junction forms a barrier layer, and a self-rectifying memristor with a diode-like effect is realized. The self-rectifying memristor is realized based on a perovskite material system for the first time, the functional characteristics of the perovskite memristor are enriched, the material selection range of the self-rectifying memristor is expanded, and the self-rectifying memristor is a low-cost design, and can meet the information accurate reading requirement of a storage unit in a high-integration cross array.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of micro-nano electronic manufacturing and storage, and proposes a self-rectifying memristor meeting the demand of accurate information reading in a crossbar array structure. BACKGROUND

[0002] With the continuous popularity of portable electronic devices, as a new type of non-volatile memory, the share of memristor in the entire storage market is getting larger and larger. There are mainly two integration modes of RRAM, namely active array (1T1R) and passive array (1D1R or 1R). Due to the size limitation of transistors (T), the structure unit size of active array 1T1R is difficult to be reduced (6F 2 , F is the feature size), and the integration density is limited, which forces people to find the next generation of array structure with superior performance. Passive crossbar array has a 4F 2 storage structure, which is 6F 2 times higher in storage density, and is highly concerned for its low cost and breakthrough in technology generation development limit.

[0003] The unit device in the crossbar array is a sandwich structure of upper electrode / resistive material layer / lower electrode, which can be reversibly converted between high resistance state (HRS) and low resistance state (LRS) through electrical signal, realizing the storage function. However, the 4F 2 type passive crossbar array has an unavoidable crosstalk current problem, which is easy to cause information misreading. The traditional method often constructs 1D1R structure to overcome the problem of crosstalk current by connecting diodes in series, however, on the one hand, this method not only increases the process complexity, but also increases the unit volume and reduces the integration density; on the other hand, the voltage division effect of diode will increase the operating voltage and increase the power consumption. If the storage unit itself has the functions of resistive change and rectification integration, the rectification function can be realized without connecting diodes in series.

[0004] It is worth noting that halogen perovskite materials have inherent electrical hysteresis characteristics, which can perfectly meet the needs of memristors for memristive materials and are welcomed in the storage field. Currently, memristors have been realized in pure inorganic perovskites [Sci. Adv. 2021; 7: eabg3788], organic-inorganic hybrid perovskites [Adv. Mater. 2018, 30, 1805454, Nat. Commun. 2022, 13, 2074]. However, so far, no perovskite material has been applied to self-rectifying memristors, which has seriously affected the accuracy of information access in the crossbar architecture of this material system. This may be related to the lattice structure or band structure of the perovskite material. Therefore, the best solution for the future development of the perovskite material system in the field of high-density and high-accuracy storage is to develop new perovskite materials and construct self-rectifying memristors of perovskite materials. SUMMARY

[0005] The technical problem solved by the present application: the self-rectifying memristor based on halogen hybrid perovskite disclosed in the present application constructs a self-rectifying memristor of perovskite material, and the prepared device Ag / (IFA)3PbI5 / ITO has good rectification and storage dual functions, wherein the rectification ratio is about 10 4 , the switching ratio is about 10 3 , which is much larger than the commercial 10 1 .

[0006] In order to solve the technical problem of the present application, the technical scheme is as follows: a self-rectifying memristor based on halogen hybrid perovskite, from bottom to top, is a strip-shaped metal Ag electrode, a perovskite (NH=CINH3)3PbI5 (abbreviation: (IFA)3PbI5) layer, and a strip-shaped electrode. The perovskite layer is sandwiched between the upper and lower electrodes arranged in a cross shape. Each cross point is a storage unit device, and all storage units are integrated on the same substrate. The storage unit in this structure not only has resistance transition performance, but also can suppress crosstalk current to ensure accurate information access.

[0007] Preferably, the perovskite (IFA)3PbI5 has a one-dimensional lattice structure and a wide band gap (~3eV).

[0008] Preferably, the halogen ions inside the (IFA)3PbI5 are extremely easy to chemically react with the electrode Ag, and a metal halide AgI layer is spontaneously formed at the interface of (IFA)3PbI5 / Ag.

[0009] Preferably, a p-n junction is formed between the (IFA)3PbI5 and AgI; the rectification mechanism of the device is that the potential barrier of the p-n junction is different under positive and negative voltages, which helps the memristor to realize the rectification function.

[0010] Preferably, the thickness of the Ag electrode is between 80-100 nm; the thickness of the (IFA)3PbI5 layer is between 500-700 nm.

[0011] Preferably, the lower electrode is commercial ITO or FTO conductive glass.

[0012] Preferably, the width of the upper and lower electrodes is between 500 nm-100 μm.

[0013] To solve the technical problems of the present application, another technical solution is proposed: the preparation method of the self-rectifying memristor based on halogen hybrid perovskite includes the following steps:

[0014] Step one: applying a solution method to form a hybrid perovskite thin film on the commercial lower electrode;

[0015] Step two: forming a metal Ag electrode on the hybrid perovskite thin film.

[0016] Preferably, the Ag electrode is prepared by thermal evaporation method, and the process conditions are as follows: power 50-200 W, pressure 10 -3 -10 -5 Pa, argon flow 10-100 sccm.

[0017] Preferably, the hybrid perovskite thin film is prepared by a solution method, and the preparation process is operated in an inert atmosphere glove box, and the specific steps include:

[0018] Step one: preparing a precursor crystal. PbI2 powder is added to a hydroiodic acid solution, argon is introduced, and after the lead iodide is fully reacted, cyanamide is added, and the mixture is uniformly cooled to obtain (IFA)3PbI5 crystal.

[0019] Step two: preparing a precursor solution. (IFA)3PbI5 crystal is dissolved in DMF, and after being fully dissolved, 17 μL, 25.5 μL, and 34 μL of DMSO solvent are added to obtain different concentrations of precursor solutions with (IFA)3PbI5 and DMSO molar ratios of 1:2, 1:3, and 1:4. DMF and DMSO are double solvents for perovskite precursors,

[0020] Step three: preparing a thin film by spin coating. The prepared precursor is spin coated on the strip-shaped electrode of commercial ITO or FTO, and the anti-solvent toluene is added within 5-10 s before the spin coating is completed.

[0021] Step four: controlling the quality of the thin film: placing the uniformly spin-coated thin film on a hot plate at 80-120℃ and annealing for 5-10 min. The hybrid perovskite thin film is prepared by a solution method, and a double-solvent precursor is selected.

[0022] The application discloses a self-rectifying memristor based on halogen hybrid perovskite, which comprises a strip-shaped metal Ag electrode, a (IFA)3PbI5 perovskite layer and a strip-shaped electrode from bottom to top.

[0023] The perovskite material (IFA)3PbI5 is chemically reacted with the electrode Ag, and a metal halide AgI layer is spontaneously and instantaneously formed at the interface of (IFA)3PbI5 / Ag, and the energy band structure of (IFA)3PbI5 and AgI is matched to form a p-n junction barrier region.

[0024] Beneficial effects

[0025] From the above technical solution, the application has the following beneficial effects: the self-rectifying memristor based on halogen hybrid perovskite provided by the application uses hybrid perovskite as a storage medium, utilizes the spontaneous formation layer (metal halide) at the perovskite / upper electrode interface and the p-n junction between the perovskite and the spontaneous formation layer, and the reverse p-n junction forms a barrier layer, so that the rectifying function of a diode is realized. The current crosstalk and other phenomena in the cross array structure can be inhibited. The device structure is simple, the device preparation process is simple, the device is multifunctional, and the device is extremely suitable for application in a cross array of a three-dimensional stacked structure, and the minimum unit area of a single-layer cross array structure is 4F 2 When the number of layers is N, the area occupied by the unit device is 4F 2 / n, so that the integrated density is high and the integrated cost is low.

[0026] The self-rectifying memristor Ag / (IFA)3PbI5 / ITO prepared by the application has the following memory mechanism: 1) the I - in (IFA)3PbI5 is easily migrated to the Ag electrode side and is chemically reacted with Ag to form an AgI layer; 2) the energy band structure of (IFA)3PbI5 and AgI is well matched to form a p-n junction; and 3) the potential barrier of the p-n junction is greatly changed under positive and negative bias, so that the rectifying characteristics of the device are realized.

[0027] The self-rectifying memristor based on halogen hybrid perovskite provided by the application has a device structure of only three layers, and comprises a strip-shaped Ag electrode, a (IFA)3PbI5 perovskite layer and a strip-shaped electrode from bottom to top.

[0028] The perovskite material (IFA)3PbI5 provided by the application has a 1D lattice structure and a wide band gap (3eV), and the band gap is wider than that of other hybrid perovskites; and the iodine ions (I - ) in the perovskite material are easily directionally migrated under the action of electric driving, and the migration ability is obviously greater than that of other hybrid perovskites.

[0029] The application provides a perovskite material (IFA) 3PbI5, which has internal I - After migration to the interface of the Ag electrode, the (IFA) 3PbI5 is prone to chemical reaction with Ag to form a AgI dielectric layer, and the band structure of the (IFA) 3PbI5 matches the AgI to form a perfect p-n junction barrier region, thus helping the device to realize self rectification.

[0030] The self-rectifying memristor based on the halogen hybrid perovskite is integrated into a high-density cross array structure, and the unidirectional conductive capacity can effectively inhibit the crosstalk current in the cross array structure.

[0031] The self-rectifying memristor based on the halogen hybrid perovskite has the characteristics of simple device structure, simple device preparation process, multifunctional device, and is extremely suitable for the demand of the cross array structure for information storage accurate memristor with high integration density and low integration cost.

[0032] As described in Example 1, when the molar ratio of (IFA) 3PbI5 to DMSO is 1:4, the prepared self-rectifying memristor has the best performance, and the prepared device Ag / (IFA) 3PbI5 / ITO has good rectification and storage dual functions, wherein the rectification ratio is about 10 4 , and the switching ratio is about 10 3 , which is much larger than the commercial 10 1 .

[0033] As described in Example 2, when the molar ratio of (IFA) 3PbI5 to DMSO is 1:2, the prepared device Ag / (IFA) 3PbI5 / ITO has good rectification and storage dual functions, wherein the rectification ratio is about 10 3 , and the switching ratio is about 10 3 .

[0034] As described in Example 3, when the molar ratio of (IFA) 3PbI5 to DMSO is 1:3, the prepared device Ag / (IFA) 3PbI5 / ITO has good rectification and storage dual functions, wherein the rectification ratio is about 10 2 , and the switching ratio is about 10 2 . BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 : Schematic diagram of crosstalk current in a cross array structure.

[0036] Figure 2 : Structure schematic diagram of the self-rectifying memristor Ag / (IFA) 3PbI5 / ITO; 101, 102 and 103 are respectively a lower electrode ITO, a group variable material (IFA) 3PbI5 and an upper electrode Ag.

[0037] Figure 3Preparation flow chart of self-rectifying memristor implemented by the application

[0038] Figure 4 SEM morphology diagram of perovskite (IFA) 3PbI5 film

[0039] Figure 5 Current-voltage curve diagram of the memristor Ag / (IFA) 3PbI5 / ITO of Example 1 of the application.

[0040] Figure 6 Data storage capacity of the self-rectifying memristor Ag / (IFA) 3PbI5 / ITO of Example 1 of the application.

[0041] Figure 7 Current-voltage curve diagram of the memristor Ag / (IFA) 3PbI5 / ITO of Example 2 of the application.

[0042] Figure 8 Current-voltage curve diagram of the memristor Ag / (IFA) 3PbI5 / ITO of Example 3 of the application.

[0043] Figure 9 Current-voltage curve diagram of the memristor Ag / AgI / (IFA) 3PbI5 / ITO of Comparative Example 1 of the application.

[0044] Figure 10 Current-voltage curve diagram of the memristor Au / (IFA) 3PbI5 / ITO of Comparative Example 2 of the application. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the embodiments of the application. The described embodiments are only some of the embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work are within the protection scope of the application.

[0046] Example 1

[0047] The self-rectifying memristor based on halogen hybrid perovskite proposed in this embodiment has the ability to suppress cross-talk current in crossbar array.

[0048] As shown in Figure 1 , the high resistance state HRS(1,1) is the storage unit to be read: when the storage unit has no rectification characteristic, the current will preferentially flow through the low resistance state LRS storage unit, bypassing the selected HRS(1,1) unit, causing information reading error, as shown by the dashed line in Figure 1 ; when the storage unit has rectification characteristic, the current only flows through the selected high resistance state unit, realizing accurate information reading, as shown by the solid line inFigure 1 The middle solid line.

[0049] The single storage unit of the self-rectifying memristor based on halogen hybrid perovskite proposed in the embodiment is Ag / (IFA)3PbI5 / ITO, as shown in the figure, the metal Ag electrode, perovskite (IFA)3PbI5, and commercial ITO electrode are sequentially arranged from top to bottom, and the preparation process is as shown in the figure. Figure 2 Figure 3

[0050] The perovskite material (IFA)3PbI5 layer is prepared by a solution method, and the specific process is as follows:

[0051] Step one: preparation of precursor crystals. PbI2 powder is added to a 75℃ hydroiodic acid aqueous solution, argon is introduced, and after the lead iodide is fully reacted, 4.0 mmol of cyanamide is added to the solution, and then placed on a magnetic stirrer for uniform stirring. The precipitate obtained after the mixed solution is cooled is pure (IFA)3PbI5 crystals.

[0052] Step two: preparation of precursor solution by using DMF and DMSO double solvents. 160 μL of DMF is used to dissolve 168.8 mg of (IFA)3PbI5 crystals, and after being fully dissolved, 34 μL of DMSO solvent is added, and then placed on a magnetic stirrer for oscillation for 2 hours to obtain a precursor solution with a molar ratio of (IFA)3PbI5 to DMSO of 1:3.

[0053] Step three: preparation of perovskite thin film. The prepared precursor solution is dropped onto a commercial ITO strip-shaped electrode (with a width of 50 μm), and after soaking for 10 s, spin coating is started, and 5 s before the end of spin coating, toluene is added as an anti-solvent to remove residual solvents and accelerate the crystallization speed of perovskite on the substrate. The obtained thin film is placed on a 100℃ hot plate for annealing for 5 min to obtain a (IFA)3PbI5 thin film with a thickness of about 700 nm.

[0054] Step four: characterization of the morphology of the perovskite thin film. The morphology structure of the obtained thin film is characterized by SEM technology, as shown in the figure, the perovskite thin film is uniform and dense. Figure 4

[0055] The thickness of the metal Ag electrode in the embodiment is 80 nm, and the width is 30 μm, which is prepared by a thermal evaporation method, and the process conditions are: power 100 W, pressure 10 -4 Pa, argon flow rate 50 sccm.

[0056] The 4200 semiconductor test system is used to detect the current-voltage relationship of the device Ag / (IFA)3PbI5 / ITO in the embodiment, as shown in the figure. Figure 5 ​​​The device is always in high resistance state in the positive voltage range; in the negative voltage range, the device appears high and low resistance states, and storage behavior appears.

[0057] The asymmetric electrical properties of the device Ag / (IFA)3PbI5 / ITO under positive and negative voltages prepared in this embodiment illustrate the excellent rectification and storage characteristics of the device.

[0058] The device Ag / (IFA)3PbI5 / ITO prepared in this embodiment has good rectification and storage dual functions, and the rectification ratio is about 10 4 , and the switching ratio is about 10 3 , which is much larger than the commercial 10 1 .

[0059] The self-rectifying memristor Ag / (IFA)3PbI5 / ITO prepared in this embodiment has the following memristor mechanism analysis: 1), I - in (IFA)3PbI5 is easily migrated to the side of Ag electrode and reacts with Ag to form AgI layer; 2) (IFA)3PbI5 and AgI have good energy band structure matching to form p-n junction; 3) the potential barrier of p-n junction changes greatly under positive and negative bias, which promotes the device to realize rectification characteristics.

[0060] Example 2

[0061] The perovskite material (IFA)3PbI5 layer is prepared by a double solvent method, and the specific process is as follows:

[0062] Step one: prepare precursor crystals. PbI2 powder is added to a 75℃ hydroiodic acid aqueous solution, argon is introduced, and after the lead iodide is fully reacted, 4.0 mmol of cyanamide is added to the solution, which is then placed on a magnetic stirrer for uniform stirring. The obtained precipitate after the mixed solution is cooled is pure (IFA)3PbI5 crystals.

[0063] Step two: prepare a precursor solution using DMF and DMSO double solvents. 160 μL of DMF is used to dissolve 168.8 mg of (IFA)3PbI5 crystals, and after complete dissolution, 17 μL of DMSO solvent is added, which is then placed on a magnetic stirrer for oscillation for 2 hours to obtain a precursor solution with a molar ratio of (IFA)3PbI5 to DMSO of 1:4.

[0064] Step three: prepare a perovskite thin film. The prepared precursor solution is dropped onto a commercial ITO strip electrode (width 100 μm), and after soaking for 10 s, spin coating is started, and 10 s before the end of spin coating, anti-solvent toluene is added to remove residual solvents and accelerate the crystallization speed of perovskite on the substrate. The obtained thin film is placed on a 100℃ hot plate for annealing for 5 min to obtain a uniform and dense perovskite thin film with a thickness of about 500 nm.

[0065] The thickness of the metal Ag electrode in this embodiment is 100 nm, and the width is 100 μm. The electrode is prepared by a thermal evaporation method, and the process conditions are as follows: power, 200 W; pressure, 10 -3 Pa; argon flow rate, 100 sccm.

[0066] In this embodiment, the 4200 semiconductor test system is used to detect the current-voltage relationship of the device Ag / (IFA)3PbI5 / ITO, as shown in FIG. 4. In the positive voltage range, the device is always in a high resistance state; in the negative voltage range, the device appears in a high and low resistance state, and a storage behavior appears. Figure 7

[0067] The asymmetric electrical relationship of the device Ag / (IFA)3PbI5 / ITO prepared in this embodiment under positive voltage and negative voltage indicates that the device has excellent rectification and storage characteristics.

[0068] The device Ag / (IFA)3PbI5 / ITO prepared in this embodiment has good rectification and storage dual functions, in which the rectification ratio is about 10 3 , and the switching ratio is about 10 3 .

[0069] The self-rectifying memristor Ag / (IFA)3PbI5 / ITO prepared in this embodiment has the following mechanism analysis: 1) I - in (IFA)3PbI5 is easily migrated to the side of the Ag electrode and reacts with Ag to form an AgI layer; 2) (IFA)3PbI5 and AgI have good energy band structure matching, forming a p-n junction; 3) the potential barrier of the p-n junction changes greatly under positive and negative bias, which promotes the device to realize the rectification characteristics.

[0070] Embodiment 3

[0071] The perovskite material (IFA)3PbI5 layer is prepared by a double solvent method, and the specific process is as follows:

[0072] Step one: prepare the precursor crystal. PbI2 powder is added to a 75℃ hydroiodic acid aqueous solution, argon is introduced, and after the lead iodide is fully reacted, 4.0 mmol of cyanamide is added to the solution, and then placed on a magnetic stirrer for uniform stirring. The obtained precipitate after the mixed solution is cooled is a pure (IFA)3PbI5 crystal.

[0073] ​Step two: Preparation of precursor solution by using DMF and DMSO. 168.8 mg of (IFA)3PbI5crystal was dissolved in 160 μL of DMF, and 25.5 μL of DMSO was added dropwise after the crystal was completely dissolved. The solution was placed on a magnetic stirrer for 2 hours to obtain a precursor solution with a molar ratio of (IFA)3PbI5to DMSO of 1:2.

[0074] Step three: Preparation of perovskite film. The prepared precursor solution was dropped onto a commercial FTO strip electrode (width: 50 μm), and the electrode was immersed for 10 s and then spin-coated. Toluene was added dropwise within 5 s before the end of the spin-coating to remove residual solvent and accelerate the crystallization of perovskite on the substrate. The obtained film was placed on a hot plate at 100 °C for annealing for 5 min to obtain a uniform and dense perovskite film with a thickness of about 600 nm.

[0075] The thickness of the metal Ag electrode in this example was 80 nm, and the width was 500 nm. The electrode was prepared by a thermal evaporation method under the following process conditions: power 50 W, pressure 10 -5 Pa, argon flow rate 10 sccm.

[0076] The current-voltage relationship of the device Ag / (IFA)3PbI5 / ITO prepared in this example was detected by using a 4200 semiconductor test system, as shown in FIG. 2. In the positive voltage range, the device was always in a high resistance state; in the negative voltage range, the device appeared in a high and low resistance state, and a storage behavior was observed. Figure 8

[0077] The asymmetric electrical properties of the device Ag / (IFA)3PbI5 / ITO prepared in this example in the positive and negative voltage ranges indicate excellent rectification and storage characteristics of the device.

[0078] The device Ag / (IFA)3PbI5 / ITO prepared in this example has good rectification and storage functions, and the rectification ratio is about 10 2 , and the on-off ratio is about 10 2 .

[0079] The mechanism analysis of the self-rectifying memristor Ag / (IFA)3PbI5 / ITO prepared in this example is as follows: 1) I - in (IFA)3PbI5easily migrates to the side of the Ag electrode and reacts with Ag to form an AgI layer; 2) the energy band structure of (IFA)3PbI5and AgI matches well, forming a p-n junction; 3) the potential barrier of the p-n junction changes greatly under positive and negative bias, which promotes the device to achieve rectification characteristics.

[0080] Comparative Example 1

[0081] ​The device preparation process of this example is the same as example 1, except that a layer of AgI with a thickness of about 10 nm is evaporated on the perovskite (IFA) 3PbI5 by thermal evaporation method, and the obtained device structure is Ag / AgI / (IFA) 3PbI5 / ITO.

[0082] The device performance testing method of this comparative example is the same as example 1, and the current-voltage curve of the obtained device is as shown in Figure 7 The resistance values of the high and low resistance states of the device are consistent with those of the device Ag / (IFA) 3PbI5 / ITO; the rectification and storage performances are consistent.

[0083] The performance of the device of this comparative example proves that there is a potential barrier region between (IFA) 3PbI5 and AgI, which confirms the rectification mechanism in example 1.

[0084] Comparative example 2

[0085] The device preparation method and process of this comparative example are the same as example 1, except that the upper electrode is metal Au, and the obtained device structure is Au / (IFA) 3PbI5 / ITO.

[0086] The device performance testing method of this example is the same as example 1, and the current-voltage curve of the obtained device is as shown in Figure 8 The high and low resistance states appear in the positive and negative voltage ranges; it is a bipolar non-volatile memory device; compared with the comparative devices Ag / (IFA) 3PbI5 / ITO and Ag / AgI / (IFA) 3PbI5 / ITO, the resistance values of the high and low resistance states of this device are reduced by nearly 3 orders of magnitude.

[0087] The resistance values of the high and low resistance states of the device Au / (IFA) 3PbI5 / ITO of this comparative example are smaller, which proves that the AgI dielectric layer in the devices Ag / (IFA) 3PbI5 / ITO and Ag / AgI / (IFA) 3PbI5 / ITO produces a voltage division effect, reducing the current values of the devices in example 1 and comparative example 1; and again confirms the rectification mechanism in example 1.

Claims

1. A halogen-hybrid perovskite-based self-rectifying memristor, characterized in that: The bar-shaped metal Ag electrode, the perovskite (NH=CINH3)3PbI5 layer and the bar-shaped electrode are arranged in sequence from bottom to top, the perovskite layer is clamped in the middle by the cross arrangement of the upper and lower electrodes, each intersection point is a storage cell device, all the storage cells are integrated on the same substrate, the storage cells not only have resistance transition performance, but also can inhibit crosstalk current and ensure accurate information access; The perovskite (NH=CINH3)3PbI5 has a one-dimensional lattice structure and a wide band gap of 3 eV; The halogen ions in the (NH=CINH3)3PbI5 are extremely easy to chemically react with the electrode Ag, and a metal halide AgI layer is spontaneously formed at the interface of (NH=CINH3)3PbI5 / Ag; A p-n junction is formed between the (NH=CINH3)3PbI5 and AgI, the potential barrier of the p-n junction is different under positive and negative voltages, and the memristor realizes the rectification function; The perovskite thin film is prepared by a solution method, and the specific steps include: Step one: preparing a precursor crystal: PbI2 powder is added into a hydriodic acid solution, argon is introduced, and after the lead iodide is fully reacted, cyanamide is added, and the (NH=CINH3)3PbI5 crystal is obtained after the mixture is uniformly mixed and cooled; Step two: preparing a precursor solution: the (NH=CINH3)3PbI5 crystal is dissolved in DMF, and after being fully dissolved, DMSO solvent is added dropwise to obtain different concentrations of precursor solutions with a (NH=CINH3)3PbI5 and DMSO molar ratio of 1:2, 1:3 and 1:4, wherein DMF and DMSO are the double solvents of the perovskite precursor, Step three: preparing a thin film by a spin coating method: the prepared precursor is spin-coated on the bar-shaped electrode of a commercial ITO or FTO, and toluene, a reverse solvent, is added dropwise within 5-10 s before the spin coating is completed; Step four: regulating the quality of the thin film: the uniformly spin-coated thin film is placed on a hot plate at 80-120 ℃, and annealed for 5-10 min.

2. The halogen-hybrid perovskite-based self-rectifying memristor of claim 1, wherein, The thickness of the Ag electrode is between 80-100 nm, and the thickness of the (NH=CINH3)3PbI5 layer is between 500-700 nm.

3. The halogen-hybrid perovskite-based self-rectifying memristor of claim 1, wherein, The lower electrode is a commercial ITO or FTO conductive glass.

4. The halogen-hybrid perovskite-based self-rectifying memristor of claim 1, wherein, The width of the upper and lower electrodes is between 500 nm-100 mm.

5. The method of claim 1, wherein the halogen-hybrid perovskite-based self- rectifying memristor is prepared by the steps of: The method includes the following steps: Step one: applying a solution method to form a hybrid perovskite thin film on the lower electrode; Step two: forming a metal Ag electrode on the hybrid perovskite thin film.

6. The method of claim 5, wherein the halogen-hybrid perovskite-based self- rectifying memristor is prepared by the steps of: The Ag electrode is prepared by thermal evaporation method, and the process conditions are as follows: power 50-200W, pressure 10 -3 -10 -5 Pa, argon flow rate 10-100sccm.

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