Gallium oxide memristor and preparation method thereof
The Ga2O3 and SnO2 functional layers were prepared on the bottom electrode using inkjet printing technology, which solved the problems of narrow selection range of memristor materials and complex preparation methods, and achieved low-cost and high-stability gallium oxide memristor preparation.
Patent Information
- Application Number
- CN202510164189.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-14
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2045-02-14
AI Technical Summary
Existing memristor materials have a narrow selection range, complex preparation methods, and high costs.
The Ga2O3 and SnO2 functional layers are sequentially prepared on the bottom electrode using inkjet printing technology, and the top electrode is prepared thereon. The specific steps include coating the Ga2O3 precursor solution, drying and calcining, then coating the SnO2 precursor solution, drying and calcining, and finally preparing the top electrode.
The preparation process is simplified, the production cost is reduced, and the prepared gallium oxide memristor maintains stable electrical characteristics during multiple cycle operations, with high repeatability and stability.
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Figure CN119907621B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of semiconductor, in particular to a gallium oxide memristor and a preparation method thereof. BACKGROUND
[0002] The concept of memristor was first proposed by Professor Chua of the University of California, Berkeley in 1971, based on in-depth exploration of the internal mathematical logical relationship between voltage (V), current (I), magnetic flux (Φ) and charge quantity (q), and ensuring the integrity thereof. According to theoretical derivation, it should satisfy the mathematical expression d = Mdq, wherein M is the mathematical representation of the memristor. Although the birth of the concept of memristor can be traced back to 1971, it was not until 2008 that the Hewlett-Packard Laboratory first confirmed the real existence of the memristor in the real world through physical experiments and built a corresponding memristor model. At present, the research in the field of memristor is still in its infancy, and mature commercial products have not yet been put on the market, so it is of great academic value and practical significance to carry out in-depth research on the selection of material system, the design of device structure and the optimization of preparation process of memristor.
[0003] According to relevant research reports, memristor materials can be roughly classified into oxides, sulfide solid electrolytes, nitrides and other inorganic materials, and oxides can be further divided into binary oxides, ternary oxides and multi-component oxides. At present, among various materials used for preparing memristors, metal oxides are mostly selected from semiconductor materials such as ZnO, TiO2, ZrO2, NiO, BiFeO3, SrTiO3, Fe2O3, etc. As a new emerging memristor material, Ga2O3 has relatively few relevant research reports, so it can be seen that in-depth research on SnO2 / Ga2O3 memristor is expected to fill the gap in the field and has a very far-reaching significance.
[0004] From the perspective of structure and function, a memristor is mainly composed of upper and lower electrodes and a functional layer with resistance change performance sandwiched therebetween, and the resistance change mechanism and performance of the memristor are closely related to the material selected for the functional layer. In addition, when preparing the functional layer of a metal oxide memristor, traditional preparation methods often use vacuum vapor deposition techniques such as electron beam evaporation and magnetron sputtering, but these methods have the disadvantages of strict equipment requirements and high preparation cost. Therefore, it is necessary to seek a new type of memristor with an economical and convenient preparation method. SUMMARY
[0005] Therefore, the purpose of the present application is to provide a gallium oxide memristor and a preparation method thereof, which can solve the problems of narrow selection range of existing memristor materials and complex preparation method of memristor.
[0006] To achieve the above technical purposes, the application provides a preparation method of a gallium oxide memristor, and the specific steps are as follows:
[0007] In step S1, a Ga2O3 precursor solution is coated on a bottom electrode by inkjet printing, and a Ga2O3 / bottom electrode layer is obtained through drying and calcination.
[0008] In step S2, a SnO2 precursor solution is coated on the Ga2O3 layer by inkjet printing, and a SnO2 / Ga2O3 / bottom electrode layer is obtained through drying and calcination.
[0009] In step S3, a top electrode is prepared on the SnO2 layer by inkjet printing, and a gallium oxide memristor with a top electrode / SnO2 / Ga2O3 / bottom electrode is obtained through drying.
[0010] Further, the Ga2O3 precursor solution is prepared by dissolving gallium nitrate and a thickening agent in a solvent, and then stirring and aging; and the SnO2 precursor solution is prepared by dissolving tin tetrachloride and a thickening agent in a solvent, and then stirring and aging.
[0011] Further, in the Ga2O3 precursor solution, the molar concentration of Ga 3+ is 0.4-0.6 mol / L, and the mass concentration of the thickening agent is 20-40 g / L; and in the SnO2 precursor solution, the molar concentration of Sn 4+ is 0.2-0.4 mol / L, and the mass concentration of the thickening agent is 40-80 g / L.
[0012] Further, the thickening agent is citric acid, and the solvent is water.
[0013] Further, in step S1, the calcination temperature is 550 DEG C, and the calcination time is 1 h; and in step S2, the calcination temperature is 350 DEG C, and the calcination time is 1 h.
[0014] The gallium oxide memristor provided by the embodiment of the application comprises a bottom electrode, a Ga2O3 layer, a SnO2 layer and a top electrode arranged in sequence.
[0015] Further, the thickness of the SnO2 layer is 100-200 nm, and the thickness of the Ga2O3 layer is 100-200 nm.
[0016] Further, the bottom electrode is an FTO film with a thickness of 50-300 nm, and the top electrode is Ag with a thickness of 100-300 nm.
[0017] In summary, the application provides a preparation method of gallium oxide memristor. Specifically, on the surface of the bottom electrode, a Ga2O3 layer, a SnO2 layer are prepared in sequence by means of inkjet printing, and finally a top electrode is prepared. The gallium oxide memristor obtained by this preparation process exhibits excellent cycle performance, and its electrical characteristics can always remain stable during multiple cycle operations. This indicates that the memristor prepared by taking Ga2O3 as the memristor material and combining the inkjet printing process has excellent stability within the working cycle, and also provides a strong guarantee for its stability in practical application. Compared with the prior art, the application discards the traditional magnetron sputtering method in the preparation process, and instead adopts the inkjet printing technology which is more cost-effective, which greatly simplifies the preparation process and reduces the production cost; at the same time, the gallium oxide memristor prepared by the application also has higher repeatability and stability, which can effectively guarantee the stability of the device performance in the actual operation process. BRIEF DESCRIPTION OF DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.
[0019] Figure 1 a schematic diagram of the gallium oxide memristor provided by the embodiments of the present application;
[0020] Figure 2 the I-V curve diagram of the gallium oxide memristor provided by the embodiments of the present application after one cycle;
[0021] Figure 3 the I-V curve diagram of the gallium oxide memristor provided by the embodiments of the present application after one hundred cycles;
[0022] Figure 4 the I-V curve diagram of the gallium oxide memristor provided by the embodiments of the present application after two hundred cycles;
[0023] Figure 5 the I-V curve diagram of the gallium oxide memristor provided by the embodiments of the present application after three hundred cycles. DETAILED DESCRIPTION
[0024] The technical solutions of the embodiments of the present application will be described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of the present application.
[0025] Wherein, all raw materials of the present application have no particular restrictions on their sources, and can be purchased on the market or prepared according to conventional methods well known to those skilled in the art.
[0026] The embodiment of the present application provides a preparation method of a gallium oxide memristor, and the specific steps are as follows:
[0027] In step S1, a Ga2O3 precursor solution is coated on a bottom electrode by inkjet printing, and a Ga2O3 / bottom electrode layer is obtained through drying and calcination.
[0028] In step S2, a SnO2 precursor solution is coated on the Ga2O3 layer by inkjet printing, and a SnO2 / Ga2O3 / bottom electrode layer is obtained through drying and calcination.
[0029] In step S3, a top electrode is prepared on the SnO2 layer by inkjet printing, and a gallium oxide memristor with a top electrode / SnO2 / Ga2O3 / bottom electrode is obtained through drying.
[0030] It should be noted that when the bottom electrode is an FTO conductive glass substrate, the FTO conductive glass substrate can be cleaned before use by the following method: the FTO conductive glass substrate is sequentially immersed in deionized water, anhydrous ethanol and deionized water, and ultrasonic cleaning is performed for 10 min, and then the FTO conductive glass substrate is dried with a nitrogen gun for standby. It should be further noted that inkjet printing, as a branch of solution gel method, has the advantages of simple process and low cost, and compared with the spin coating method, the thin film prepared by using the inkjet printing method performs better in uniformity and density; when the inkjet printing is used to prepare the functional layer such as SnO2 / Ga2O3, in order to further improve the uniformity of the inkjet printing, multiple "spraying-drying" can be adopted for each layer, that is, drying is performed after each spraying, and the next spraying is performed. Through multiple such cycle operations, each layer of material can be distributed more uniformly on the surface of the bottom electrode, and the problem of uneven thickness caused by single spraying can be reduced, so that the overall quality of the functional layer is improved.
[0031] In some embodiments, the Ga2O3 precursor solution is prepared by dissolving gallium nitrate and a thickening agent in a solvent, and then stirring and aging; the SnO2 precursor solution is prepared by dissolving tin tetrachloride and a thickening agent in a solvent, and then stirring and aging.
[0032] Specifically, the aging time is 24 h.
[0033] Preferably, in the Ga2O3 precursor solution, Ga 3+The molar concentration of Sn is 0.4-0.6 mol / L, and the mass concentration of the thickening agent is 20-40 g / L. 4+ The molar concentration of Sn is 0.2-0.4 mol / L, and the mass concentration of the thickening agent is 40-80 g / L.
[0034] Specifically, the thickening agent is citric acid, and the solvent is water.
[0035] In some embodiments, in step S1, the calcination temperature is 550 DEG C, and the calcination time is 1 h; in step S2, the calcination temperature is 350 DEG C, and the calcination time is 1 h.
[0036] The embodiment of the application provides a gallium oxide memristor, which comprises a bottom electrode, a Ga2O3 layer, a SnO2 layer and a top electrode arranged in sequence.
[0037] In some embodiments, the thickness of the SnO2 layer is 100-200 nm, and the thickness of the Ga2O3 layer is 100-200 nm; the bottom electrode is an FTO film with a thickness of 50-300 nm; and the top electrode is Ag with a thickness of 100-300 nm.
[0038] The applicant further provides the following reference specific embodiments for describing the application, and it should be noted that these embodiments are merely descriptive, and do not limit the application in any way.
[0039] Embodiment 1
[0040] The embodiment provides a preparation method of a gallium oxide memristor, and the specific steps are as follows:
[0041] Step S1, preliminary preparation:
[0042] Cleaning the substrate: the FTO conductive glass substrate is sequentially immersed in deionized water, anhydrous ethanol and deionized water, and is subjected to 10 min of cleaning operation by ultrasonic, and after cleaning, the FTO conductive glass substrate is blown dry by a nitrogen gun for standby use;
[0043] Preparation of Ga2O3 precursor solution: take gallium nitrate hydrate in deionized water to obtain a gallium nitrate solution with a molar concentration of 0.5 mol / L, add citric acid to the gallium nitrate solution to obtain a mixed solution with a mass concentration of citric acid of 30 g / L, place the mixed solution on a magnetic stirrer and stir for 2 h, and then age for 24 h to obtain a Ga2O3 precursor solution with a molar concentration of gallium ions of 0.5 mol / L;
[0044] Preparation of SnO2 precursor solution: take tin tetrachloride hydrate in deionized water to obtain a tin tetrachloride solution with a molar concentration of 0.3 mol / L, add citric acid to the tin tetrachloride solution to obtain a mixed solution with a mass concentration of citric acid of 60 g / L, stir the mixed solution on a magnetic stirrer for 2 h, and then age for 24 h to obtain a SnO2 precursor solution with a molar concentration of tin ions of 0.3 mol / L;
[0045] Step S2, preparation of Ga2O3 layer: take the Ga2O3 precursor solution prepared in step 1 and use inkjet printing to coat it on a standby FTO conductive glass substrate with a length of 10 cm and a width of 10 cm, dry the coated conductive glass substrate on a heating platform at 100 ℃ for 3 min, repeat the "inkjet-drying" step 3 times, obtain the FTO conductive glass substrate with a Ga2O3 precursor solution layer on the surface, and then place it in a muffle furnace at a temperature of 550 ℃ for 1 h to obtain a Ga2O3 / FTO layer;
[0046] Step S3, preparation of SnO2 layer: take the SnO2 precursor solution prepared in step 1 and use inkjet printing to coat it on the Ga2O3 / FTO layer prepared in step S2, dry the coated Ga2O3 / FTO layer at a temperature of 150 ℃ for 10 min, repeat the "inkjet-drying" step 3 times, obtain the Ga2O3 / FTO layer with a SnO2 precursor solution layer on the surface, and then place it in a muffle furnace at a temperature of 350 ℃ for 1 h to obtain a SnO2 / Ga2O3 / FTO layer;
[0047] Step S4, preparation of top electrode: use inkjet printing to prepare an Ag electrode with a diameter of 1 mm on the SnO2 layer of the SnO2 / Ga2O3 / FTO layer, and then dry it on a heating platform at a temperature of 100 ℃ for 5 min to finally obtain an Ag / SnO2 / Ga2O3 / FTO heterojunction memristor.
[0048] Example 2
[0049] The embodiment provides a preparation method of a gallium oxide memristor, and the specific steps are as follows:
[0050] Step S1, preliminary preparation:
[0051] Cleaning the substrate: immerse the FTO conductive glass substrate in deionized water, anhydrous ethanol and deionized water in sequence, and perform ultrasonic cleaning operation for 10 min, and then blow dry the FTO conductive glass substrate with a nitrogen gun for standby use;
[0052] Preparation of Ga2O3 precursor solution: gallium nitrate hydrate was dissolved in deionized water to obtain a gallium nitrate solution with a molar concentration of 0.4 mol / L, and citric acid was added to the gallium nitrate solution to obtain a mixed solution with a mass concentration of citric acid of 40 g / L. The mixed solution was stirred on a magnetic stirrer for 2 h, and then aged for 24 h to obtain a Ga2O3 precursor solution with a molar concentration of gallium ions of 0.4 mol / L;
[0053] Preparation of SnO2 precursor solution: tin tetrachloride hydrate was dissolved in deionized water to obtain a tin tetrachloride solution with a molar concentration of 0.2 mol / L, and citric acid was added to the tin tetrachloride solution to obtain a mixed solution with a mass concentration of citric acid of 80 g / L. The mixed solution was stirred on a magnetic stirrer for 2 h, and then aged for 24 h to obtain a SnO2 precursor solution with a molar concentration of tin ions of 0.2 mol / L;
[0054] Step S2, preparation of Ga2O3 layer: the Ga2O3 precursor solution prepared in step 1 was coated on a FTO conductive glass substrate with a length of 10 cm and a width of 10 cm by inkjet printing. The coated conductive glass substrate was placed on a heating platform at 100°C and dried for 3 min. The "inkjet-drying" step was repeated 3 times to obtain a FTO conductive glass substrate with a Ga2O3 precursor solution layer on the surface. Then it was placed in a muffle furnace at a temperature of 550°C and annealed for 1 h to obtain a Ga2O3 / FTO layer;
[0055] Step S3, preparation of SnO2 layer: the SnO2 precursor solution prepared in step 1 was coated on the Ga2O3 / FTO layer prepared in step S2 by inkjet printing. The coated Ga2O3 / FTO layer was placed in a drying oven at 150°C and dried for 10 min. The "inkjet-drying" step was repeated 3 times to obtain a Ga2O3 / FTO layer with a SnO2 precursor solution layer on the surface. Then it was placed in a muffle furnace at a temperature of 350°C and annealed for 1 h to obtain a SnO2 / Ga2O3 / FTO layer;
[0056] Step S4, preparation of top electrode: an Ag electrode with a diameter of 1 mm was prepared on the SnO2 layer of the SnO2 / Ga2O3 / FTO layer by inkjet printing. Then it was placed on a heating platform at 100°C and dried for 5 min. Finally, an Ag / SnO2 / Ga2O3 / FTO heterojunction memristor was obtained.
[0057] The difference between Example 1 and Example 2 is that the concentrations of the substances in the precursor solution are different, as follows:
[0058] Ga2O3 precursor solution Ga 3+0.4 mol / L; the mass concentration of citric acid is 40 g / L;
[0059] Sn in SnO2 precursor solution 4+ 0.2 mol / L; the mass concentration of citric acid is 80 g / L.
[0060] Example 3
[0061] The embodiment provides a preparation method of a gallium oxide memristor, and the specific steps are as follows:
[0062] Step S1, preliminary preparation:
[0063] Cleaning the substrate: the FTO conductive glass substrate is sequentially immersed in deionized water, anhydrous ethanol and deionized water, and is subjected to 10 min of cleaning operation by ultrasonic, and after the cleaning is completed, the FTO conductive glass substrate is blown dry by using a nitrogen gun for standby use;
[0064] Preparation of Ga2O3 precursor solution: nitric acid gallium hydrate is dissolved in deionized water to obtain a nitric acid gallium solution with a molar concentration of 0.6 mol / L, citric acid is added to the nitric acid gallium solution to obtain a mixed solution with a mass concentration of citric acid of 20 g / L, the mixed solution is placed on a magnetic stirrer and stirred for 2 h, and then aged for 24 h, to obtain a Ga2O3 precursor solution with a molar concentration of gallium ions of 0.6 mol / L;
[0065] Preparation of SnO2 precursor solution: tin tetrachloride hydrate is taken in deionized water to obtain a tin tetrachloride solution with a molar concentration of 0.4 mol / L, citric acid is added to the tin tetrachloride solution to obtain a mixed solution with a mass concentration of citric acid of 40 g / L, the mixed solution is placed on a magnetic stirrer and stirred for 2 h, and then aged for 24 h, to obtain a SnO2 precursor solution with a molar concentration of tin ions of 0.4 mol / L;
[0066] Step S2, preparation of a Ga2O3 layer: the Ga2O3 precursor solution prepared in step 1 is coated on the standby FTO conductive glass substrate with a length of 10 cm and a width of 10 cm by using an inkjet printing method, the coated conductive glass substrate is placed on a heating platform at 100 DEG C and dried for 3 min, the step of "inkjet-drying" is repeated 3 times, to obtain an FTO conductive glass substrate with a Ga2O3 precursor solution layer on the surface, and then the FTO conductive glass substrate is placed in a muffle furnace at a temperature of 550 DEG C and annealed for 1 h, to obtain a Ga2O3 / FTO layer.
[0067] Step S3, preparing a SnO2 layer: the SnO2 precursor solution prepared in step 1 is coated on the Ga2O3 / FTO layer prepared in step S2 by inkjet printing, the coated Ga2O3 / FTO layer is dried at 150°C for 10 min, and the "inkjet-drying" step is repeated three times to obtain a Ga2O3 / FTO layer covered with a SnO2 precursor solution layer on the surface, which is then annealed in a muffle furnace at 350°C for 1 h to obtain a SnO2 / Ga2O3 / FTO layer;
[0068] Step S4, preparing the top electrode: an Ag electrode with a diameter of 1 mm was prepared on the SnO2 layer of the SnO2 / Ga2O3 / FTO layer by inkjet printing, and then placed on a heating platform at 100°C for 5 minutes to dry, finally obtaining an Ag / SnO2 / Ga2O3 / FTO heterojunction memristor.
[0069] The difference from Example 1 is that the concentration of the substances in the precursor solution is different, as follows:
[0070] Ga in Ga2O3 precursor solution 3+ The molar concentration of citric acid is 0.6 mol / L; the mass concentration of citric acid is 20 g / L;
[0071] Sn in SnO2 precursor solution 4+ The molar concentration of is 0.4 mol / L; the mass concentration of citric acid is 40 g / L.
[0072] Test: Cycle number test
[0073] The memristor prepared in Example 1 was subjected to electrical testing. Figure 1 As shown, during the test, a voltage is applied to the bottom electrode and the top electrode is always kept grounded. Under this condition, the memristor is cycled multiple times and its DC IV curve after the cycle is tested.
[0074] The measured IV characteristic curve is as follows: Figures 2-5 A comparative analysis of the IV characteristic curves of the memristor after the first, 100th, 200th, and 300th cycles reveals that the memristor exhibits a significant on-off ratio of up to 10² and excellent stability. Even after 300 cycles, its on-off ratio shows no degradation. This demonstrates the excellent stability of memristors fabricated using Ga2O3 as the memristor material and inkjet printing.
[0075] The above are preferred embodiments of the present application, and are not used to limit the present application, and for those skilled in the art, the aforementioned examples can be modified, or some technical features can be replaced by equivalent, but any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method for preparing a gallium oxide memristor, characterized in that: The following steps are involved: Step S1, coating a Ga2O3 precursor solution on the bottom electrode by inkjet printing, drying and calcining to obtain a Ga2O3 / bottom electrode layer; Step S2, coating the SnO2 precursor solution on the Ga2O3 layer by inkjet printing, drying and calcining to obtain a SnO2 / Ga2O3 / bottom electrode layer; Step S3, preparing a top electrode on the SnO2 layer by inkjet printing, and obtaining a gallium oxide memristor having a top electrode / SnO2 / Ga2O3 / bottom electrode after drying.
2. The method for preparing a gallium oxide memristor according to claim 1, wherein: The Ga2O3 precursor solution is prepared by dissolving gallium nitrate and a thickener in a solvent, followed by stirring and aging; the SnO2 precursor solution is prepared by dissolving tin tetrachloride and a thickener in a solvent, followed by stirring and aging.
3. The method for preparing a gallium oxide memristor according to claim 2, wherein: In the Ga2O3 precursor solution, Ga 3+ The molar concentration of the solvent is 0.4~0.6 mol / L, and the mass concentration of the thickener is 20~40g / L.
4. The method for preparing a gallium oxide memristor according to claim 2, wherein: In the SnO2 precursor solution, Sn 4+ The molar concentration of the solvent is 0.2~0.4 mol / L, and the mass concentration of the thickener is 40~80g / L.
5. The method for preparing a gallium oxide memristor according to claim 2, wherein: The thickener is citric acid; the solvent is water.
6. The method for preparing a gallium oxide memristor according to claim 1, wherein: In the step S1, the calcination temperature is 550° C. and the calcination time is 1 h.
7. The method for preparing a gallium oxide memristor according to claim 1, wherein: In step S2, the calcination temperature is 350° C. and the calcination time is 1 h.
8. A gallium oxide memristor, characterized in that: The gallium oxide memristor is manufactured by the preparation method of any one of claims 1 to 7, comprising a bottom electrode, a Ga2O3 layer, a SnO2 layer, and a top electrode arranged in sequence.
9. The gallium oxide memristor according to claim 8, wherein: The thickness of the SnO2 layer is 100-200 nm; the thickness of the Ga2O3 layer is 100-200 nm.
10. The gallium oxide memristor according to claim 8, characterized in that: The bottom electrode is an FTO film with a thickness of 50-300 nm; the top electrode is Ag with a thickness of 100-300 nm.