A method for growing a germanium-based rare-earth nickel-based oxide electronic phase-change material

Abstract

A germanium-based rare earth nickel oxide electronic phase change material growth method. By using germanium dioxide high oxygen pressure phase as a lattice template and nucleation site trigger, a rare earth nickel oxide in a thermodynamic metastable phase is grown in a non-uniform nucleation mode to prepare a rare earth nickel oxide / germanium dioxide high oxygen pressure phase coated structure powder, a rare earth nickel oxide polycrystal film / germanium dioxide high oxygen pressure phase transition layer / single crystal germanium heterojunction, and a rare earth nickel oxide quasi-single crystal film / germanium dioxide high oxygen pressure phase transition layer / single crystal silicon heterojunction. The prepared material has a metal insulator phase transition triggered by temperature and a hydrogen-induced electronic phase transition triggered by protons. The rare earth nickel oxide in a thermodynamic metastable phase can be grown on a silicon or germanium IV group semiconductor substrate, and the subsequent device preparation process is compatible with traditional silicon-based semiconductor technology. The prepared material has potential application value in neuron devices, mutation type thermistors, infrared camouflage, and laser weapon protection.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology and functional materials, specifically relating to a method for growing germanium-based rare earth nickel-based oxide electronic phase change materials. Background Technology

[0002] Rare earth nickel-based oxides include 113-type twisted perovskite structures (ReNiO3, where Re is a rare earth element other than La) and Ruddlesden-Popper phase layered perovskite structures ((Re... 1-x Ae x ) n+1 Ni n O 3n+1 (Re represents rare earth elements, and Ae represents alkaline earth elements), at the characteristic temperature (T MIT Under certain conditions, the rare earth elements can trigger a metal-insulator transition, changing from a low-temperature insulating phase to a high-temperature metallic phase, accompanied by a transformation in crystal structure, which in turn causes a sudden change in their physical properties [1-3]. As the radius of rare earth ions decreases, the distortion of the NiO6 octahedron in rare earth nickel-based oxides gradually increases, and the stability of the insulating phase relative to the metallic phase improves, leading to a change in T... MIT Gradually increasing [4]. Therefore, its T can be achieved through rare earth element composition design. MIT It can be flexibly controlled over a wide range of 100-600 K [5]. In addition, its electronic phase transition can be triggered by polarization electric field, characteristic pressure or chemical / electrochemical hydrogenation, which in turn causes a sudden change in resistivity [6-7]. Therefore, rare earth nickel-based oxides have potential application prospects in the fields of neuronal devices, abrupt thermistors, infrared camouflage and laser weapon protection [8-10].

[0003] However, the compatibility of rare earth nickel-based oxide materials with silicon-based technology is currently a technical barrier restricting the research and application of this material in the field of electronic devices. Rare earth nickel-based oxides are in a thermodynamically metastable phase and have a positive Gibbs formation free energy at high temperatures, making them difficult to synthesize through conventional solid-state reactions. Moreover, as the radius of rare earth ions decreases, their positive Gibbs formation free energy gradually increases, further increasing the difficulty of synthesizing this material

[11] . By utilizing the template effect of single-crystal substrates to reduce the Gibbs formation free energy, the epitaxial growth of this material can be achieved through vacuum techniques such as pulsed laser deposition or magnetron sputtering. However, since the oxide layer on the Si surface and the rare earth nickel-based oxide do not have a coherent relationship, it is difficult to achieve high-quality growth on group IV semiconductor materials, which is characterized by extremely low resistivity abrupt changes before and after the metal insulating phase transition [12-14].

[0004] In summary, there is currently a lack of an effective method in this field to achieve high-quality growth of rare-earth nickel-based oxide electronic phase change materials on group IV semiconductors such as silicon, germanium, silicon germanium, and silicon carbide. This makes it impossible to combine the application of this material in neuronal devices, abrupt thermistors, infrared camouflage, and laser weapon protection with existing silicon semiconductor processes, and its related applications are difficult to promote on a large scale.

[0005] 【1】Catalan G. Progress in perovskite nickelate Research[J]. PhaseTransitions [J], 2008, 81(7-8): 729-749.

[0006] 【2】Zhang HT, Zuo F, Li F, et al. Perovskite nickelates as bio-electronic interfaces [J]. Nature Communications, 2019, 10: 1651.

[0007] 【3】Zou F, Panda P, Kotiuga M, et al. Habituation based synapticplasticity and organismic learning in a quantum perovskite [J]. NatureCommunications, 2017, 8: 240.

[0008] 【4】Zhou Y, Guan XF, Zhou H, et al. Strongly correlated perovskitefuel cells [J]. Nature, 2016, 534: 231-234.

[0009] 【5】Chen JK, Hu HY, Wang JO, et al. Overcoming synthetic metastabilities and revealing metal-to-insulator transition & thermistor bi-functionalities for d-band correlation perovskite nickelates [J]. MaterialsHorizons, 2019, 6: 788-795.

[0010] 【6】Shi J, Zhou Y, Ramanathan S, et al. Colossal resistance switchingand band gap modulation in a perovskite nickelate by electron doping. [J].Nature Communications, 2014, 5: 4860.

[0011] 【7】Yuan Y F, Kotiuga M, Park T J, et al. Hydrogen-induced tunableremanent polarization in a perovskite nickelate [J]. Nature Communications,2024, 15: 4717.

[0012] 【8】Zhang H T, Park T J, Islam A N M, et al. Reconfigurable perovskitenickelate electronics for artificial intelligence [J]. Science, 2022, 375(6580): 533-539.

[0013] 【9】Chen J K, Li Z A, Dong H L, et al. Pressure induced unstableelectronic states upon correlated nickelates metastable perovskites as batchsynthesized via heterogeneous nucleation [J]. Advanced Functional Materials,2020, 30 (23): 2000987.

[0014]

[10] Shahsafi A, Roney P, Zhou Y, et al. Temperature-independentthermal radiation [J]. Proceedings of the National Academy of Sciences of theUnited States of America, 2019, 116 (52): 26402.

[0015]

[11] Zhang Z, Schwanz D, Narayanan B, et al. Perovskite nickelates aselectric-field sensors in salt water [J]. Nature, 2018, 553: 68-72.

[0016]

[12] Chen J K, Mao W, Ge B H, et al. Revealing the role of latticedistortions in the hydrogen-induced metal-insulator transition of SmNiO3 [J].Nature Communications, 2019, 10: 694.

[0017]

[13] Conchon F, Boulle A, Guinebreitiere R, et al. Effect of tensileand compressive strains on the transport properties of SmNiO3 layersepitaxially grown on (001) SrTiO3 and LaAlO3 substrates [J]. Applied PhysicsLetters, 2007, 91: 192110.

[0018]

[14] Li J R, Green R J, Zhang Z, et al. Sudden Collapse of MagneticOrder in Oxygen-Deficient Nickelate Films [J]. Physical Review Letters, 2021,126: 187602. Summary of the Invention

[0019] This invention provides a method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials. The main concept is based on the coherent matching relationship between germanium dioxide, which is stable under high oxygen pressure, and rare-earth nickel-based oxides. By introducing the high-oxygen-pressure phase of germanium dioxide as a lattice template and nucleation site, the forward Gibbs free energy of the reaction is reduced, triggering non-uniform nucleation and growth of the thermodynamically metastable rare-earth nickel-based oxide on its surface. This improves the growth quality and electronic phase transition characteristics of the rare-earth nickel-based oxide electronic phase change material. According to the method provided by this invention, rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase coated powders, rare-earth nickel-based oxide films / germanium dioxide high-oxygen-pressure phase transition layers / single-crystal germanium substrate heterojunctions, and rare-earth nickel-based oxide films / germanium dioxide high-oxygen-pressure phase transition layers / single-crystal silicon heterojunctions can be prepared, achieving temperature-triggered metal-insulator phase transition and proton-triggered hydrogen-induced electronic phase transition functional characteristics. The technology provided by this invention enables the growth of rare-earth nickel-based oxides with metastable phase structures on traditional group IV semiconductor substrates, such as silicon and germanium, thereby achieving compatibility of subsequent device fabrication processes with traditional silicon-based semiconductor technologies. The prepared materials have potential applications in neuronal devices, abrupt changeover thermistors, infrared camouflage, and laser weapon protection.

[0020] A method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials is characterized by introducing a germanium dioxide high-oxygen-pressure phase that has a lattice-matching relationship with the thermodynamically metastable rare-earth nickel-based oxide electronic phase change semiconductor material and is stable within the same high-oxygen-pressure range as a seed crystal or transition layer. This effectively grows composite powders of rare-earth nickel-based oxides coated with germanium dioxide high-oxygen-pressure phases, heterojunctions of rare-earth nickel-based oxides / germanium dioxide high-oxygen-pressure phases / germanium substrates, and heterojunctions of rare-earth nickel-based oxides / germanium dioxide high-oxygen-pressure phases / silicon substrates. Through the growth of the above-mentioned rare-earth nickel-based oxide materials on silicon-based and germanium-based substrates, it is compatible with traditional silicon-based semiconductor microfabrication and device fabrication processes, thereby enabling applications such as neuron devices, abrupt changeover thermistors, infrared camouflage devices, and laser weapon protective layers.

[0021] Furthermore, the seed crystal or transition layer is a germanium dioxide high-oxygen-pressure phase, which has a similar lattice constant to rare-earth nickel-based oxides and is thermodynamically stable under the high oxygen-pressure conditions required for the growth of rare-earth nickel-based oxides. It can directly encapsulate rare-earth nickel-based oxides onto germanium dioxide high-oxygen-pressure phase powder via high-oxygen-pressure molten salt reaction or hydrothermal reaction to prepare composite powders; or, first, a germanium dioxide high-oxygen-pressure phase transition layer is grown on a substrate, and then a rare-earth nickel-based oxide thin film precursor is grown using spin coating, pulsed laser deposition, magnetron sputtering, or molten salt-assisted methods and annealed under high oxygen pressure to prepare a rare-earth nickel-based oxide / germanium dioxide / substrate heterojunction thin film; or, first, a Ge transition layer is grown on a substrate and annealed under high oxygen pressure (0.2-500 MPa) at 50-1500 °C and under an ozone atmosphere at 20-300 °C. Germanium dioxide high-oxygen-pressure phase is generated by oxidation at °C and oxygen plasma oxidation. Rare earth nickel-based oxide thin film precursors are then deposited using spin coating, pulsed laser deposition, magnetron sputtering, and molten salt-assisted methods and annealed under high oxygen pressure to prepare a rare earth nickel-based oxide / germanium dioxide / substrate heterojunction thin film. In the above oxidation process of germanium dioxide and germanium under high oxygen pressure and ozone, the stoichiometry and crystal structure at the interface between the generated germanium dioxide high-oxygen-pressure phase transition layer and the silicon substrate and rare earth nickel-based oxide can be adjusted to reduce lattice mismatch.

[0022] Furthermore, the fitted rare-earth nickel-based oxide electronic phase transition material has a 113-type twisted perovskite structure with the chemical formula ReNiO3, where Re is a single rare-earth element or a combination of multiple rare-earth elements other than lanthanum, including praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), yttrium (Y), and scandium (Sc); through the rare-earth element group... The design enables the manipulation of the electronic structure of rare-earth nickel-based oxides, thereby adjusting their metal-insulator transition characteristics and hydrogen-induced electronic phase transition characteristics. The methods for synthesizing rare-earth nickel-based oxide materials include pulsed laser deposition, magnetron sputtering, hydrothermal methods, wet chemical spin coating, sol-gel methods, and molten salt methods. By changing the synthesis process, the orientation and thickness of the rare-earth nickel-based oxide electronic phase transition material can be controlled. In a preferred embodiment, magnetron sputtering is used to introduce a germanium dioxide high-oxygen-pressure phase transition layer onto Si... 0.5 Ge 0.5 The PrNiO3 material grown on the substrate is a 40 nm thick polycrystalline thin film with a phase transition temperature of 120 K; in another preferred embodiment, the EuNiO3 material grown on a single-crystal Si substrate with a germanium dioxide high-oxygen pressure phase transition layer by wet chemical spin coating is an 80 nm thick quasi-single-crystal thin film with a phase transition temperature of 475 K.

[0023] Furthermore, the fitted rare-earth nickel-based oxide electronic phase transition material also possesses a Ruddlesden-Popper phase layered perovskite structure, with the chemical formula (Re 1-x Ae x ) n+1 Ni n O 3n+1 Its structural features are a single-layer rock salt layer structure (Re 1-x Ae x O and n-layer perovskite structure (Re) 1-x Ae x The NiO3 element is arranged in alternating patterns; where Re represents a single rare earth element or a combination of multiple rare earth elements, including lanthanum (La), praseodymium (Pr), neodymium (Nd), and samarium (Sm); Ae represents an alkaline earth element; n is 1, 2, or 3, corresponding to (Re... 1-x Ae x )2NiO4、(Re 1-x Ae x )3Ni2O7、(Re 1-x Ae x )4Ni3O 10 In a preferred embodiment, La is grown on a Ge substrate with a germanium dioxide high-oxygen-pressure phase transition layer by pulsed laser deposition. 1.99 Sr 0.01 NiO4 is a 30 nm thick polycrystalline thin film, which can be used as a catalyst for the oxygen evolution reaction; in another preferred embodiment, Nd2O3 is grown on a single-crystal Si substrate with a germanium dioxide high-oxygen-pressure phase transition layer by wet chemical spin coating. 2.95 Ca 0.05 Ni2O7 material is a 40 nm thick quasi-single crystal film, which can be used for smart windows; in another preferred embodiment, Sm2Nd2Ni3O is grown on the surface of germanium dioxide high-oxygen-pressure phase seed crystals by hydrothermal method. 10 Polycrystalline powder, this coating structure can be used for wastewater treatment.

[0024] Furthermore, to synthesize germanium dioxide high-oxygen-pressure phase powder coated with rare-earth nickel-based oxides, commercial germanium dioxide can be used as a precursor to oxidize under high oxygen pressure or ozone atmosphere to obtain germanium dioxide high-oxygen-pressure phase, or germanium powder can be used as a precursor to oxidize under high oxygen pressure or ozone atmosphere to obtain germanium dioxide high-oxygen-pressure phase. The germanium dioxide high-oxygen-pressure phase powder has a curved surface shape including spherical, ellipsoidal, and cylindrical, with a size range of 0.1 μm-1 cm. Its characteristic is that its surface has an adsorption effect on rare-earth element oxides and nickel element oxide precursors in the molten flux, and has a lattice matching relationship with the fitted rare-earth nickel-based oxide, thereby promoting the non-uniform nucleation and growth of rare-earth nickel-based oxides on its surface to form a coating structure. In a preferred embodiment, spherical commercial germanium dioxide microspheres with a particle size of 100 nm are used as the core material. After high-oxygen-pressure annealing, NdNiO3 polycrystalline powder is grown on its surface by molten salt method, with a phase transition temperature of 200°C. K; In another preferred embodiment, germanium powder with a particle size of 50 nm is used as a precursor, and germanium dioxide high oxygen pressure phase seed material is obtained after annealing in an ozone atmosphere. A polycrystalline SmNiO3 coating layer is grown on its surface by hydrothermal reaction, and its phase transition temperature is 410 K.

[0025] Furthermore, to synthesize a polycrystalline rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / germanium substrate heterojunction, the germanium substrate is first annealed under MPa-level high oxygen pressure, annealed in an ozone atmosphere, or oxidized by oxygen plasma to generate a germanium dioxide high-oxygen-pressure phase transition layer. By adjusting the thickness of the transition layer and the rare-earth nickel-based oxide growth process, the preferred orientation of the polycrystalline rare-earth nickel-based oxide film can be controlled, with a thickness range of 1-1000 nm. Alternatively, glass, quartz, mica, silicon carbide, and Si can also be used. 1-x Ge x Instead of a germanium substrate, germanium is further oxidized by plasma sputtering or directly sputtered with oxygen plasma to generate a germanium dioxide high-oxygen-pressure phase. This enables the non-uniform nucleation and growth of rare-earth nickel-based oxides on the surface of the germanium dioxide high-oxygen-pressure phase transition layer into a polycrystalline thin film with preferred orientation. In a preferred embodiment, a single-crystal germanium substrate is annealed under 10 MPa oxygen pressure to obtain a 50 nm thick germanium dioxide high-oxygen-pressure phase transition layer, which is then used to prepare Nd2O3 using a wet chemical spin-coating method. 0.5 Sm 0.5 A NiO3 polycrystalline thin film with a phase transition temperature of 280 K is used. In another preferred embodiment, a 100 nm thick germanium dioxide high-oxygen-pressure phase transition layer is sputtered on a silicon carbide substrate by magnetron sputtering, and then Nd is grown on its surface by pulsed laser deposition. 0.7 Sm 0.3 NiO3 polycrystalline thin film with a phase transition temperature of 300 K.

[0026] Furthermore, to synthesize a rare-earth nickel-based oxide quasi-single-crystal film / germanium dioxide high-oxygen-pressure / silicon substrate heterojunction, a germanium dioxide high-oxygen-pressure phase transition layer is obtained by plasma sputtering of germanium followed by further oxidation or by direct sputtering with oxygen plasma. The germanium dioxide high-oxygen-pressure phase / silicon substrate heterojunction has a specific coherent matching relationship with the rare-earth nickel-based oxide, thereby reducing the Gibbs free energy of synthesis of the rare-earth nickel-based oxide and promoting its epitaxial growth. By adjusting the thickness of the transition layer and the rare-earth nickel-based oxide deposition process, the growth of a rare-earth nickel-based oxide quasi-single-crystal film can be achieved, with the transition layer thickness ranging from 1 to 1000 nm. In a preferred embodiment, Ge is sputtered on the Si surface by magnetron sputtering, and then annealed in an ozone stream to obtain an 80 nm thick germanium dioxide high-oxygen-pressure phase polycrystalline transition layer. Then, a GdNiO3 quasi-single-crystal film is prepared by pulsed laser deposition with a phase transition temperature of 520 K. In another preferred embodiment, a 30 nm thick germanium dioxide high-oxygen-pressure phase is sputtered onto a Si substrate by magnetron sputtering, and then Pr is deposited on its surface using a wet chemical spin coating method. 0.1 Nd 0.9 The NiO3 quasi-single crystal thin film has a phase transition temperature of 140K.

[0027] Furthermore, the rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / silicon substrate heterojunction prepared by this invention can be integrated with existing silicon-based semiconductor device processes to further fabricate proton-controlled neuronal devices and strongly correlated electronic devices based on electric field and temperature-triggered metal-insulator phase transitions. In a preferred embodiment, after depositing discontinuous Pt electrodes on a NdNiO3 quasi-single-crystal thin film grown on a Si substrate with a germanium dioxide high-oxygen-pressure phase transition layer, an integrated circuit is embedded. By controlling the distribution of electrical pulses and hydrogen ion gradients, the synaptic structure of human brain neurons is simulated to construct an adaptive dynamic neuronal network, significantly reducing computational energy consumption. In another preferred embodiment, a PrNiO3 quasi-single-crystal thin film is grown on a Si substrate with a germanium dioxide high-oxygen-pressure phase transition layer, and Au electrodes are introduced through laser direct writing. These electrodes are then further arranged into a specific array and embedded in an integrated circuit to achieve a temperature alarm function in the liquid nitrogen temperature range.

[0028] Furthermore, based on the abrupt change in infrared optical properties triggered by rare-earth nickel-based oxides at characteristic temperatures, the rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure / germanium substrate heterojunction grown in this invention can be used to fabricate laser weapon protective coatings and infrared camouflage devices; in a preferred embodiment, Nd2+ grown on a Ge substrate with an introduced germanium dioxide high-oxygen-pressure phase transition layer is used. 0.5 Sm 0.5 NiO3 polycrystalline thin films are arranged in a large-area array. They are transparent under visible light irradiation but undergo a metal-insulator transition under laser irradiation, resulting in a significant decrease in transmittance and a significant increase in reflectivity, thus achieving a protective effect against laser weapons. In another preferred embodiment, Nd233 is grown on a Ge substrate with a germanium dioxide high-oxygen-pressure phase transition layer.0.3 Sm 0.7 When NiO3 polycrystalline thin films are arranged in a large-area array, their infrared emissivity changes abruptly after the human body temperature triggers an electronic phase transition, thus achieving the effect of infrared camouflage near body temperature.

[0029] This invention utilizes germanium dioxide in a high-oxygen-pressure phase as a lattice template and nucleation site to trigger the heterogeneous nucleation growth of rare-earth nickel-based oxides in a thermodynamically metastable phase. This allows for the fabrication of rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase coated powders, rare-earth nickel-based oxide polycrystalline films / germanium dioxide high-oxygen-pressure phase transition layers / single-crystal germanium heterojunctions, and rare-earth nickel-based oxide quasi-single-crystal films / germanium dioxide high-oxygen-pressure phase transition layers / single-crystal silicon heterojunctions. The prepared materials exhibit temperature-triggered metal-insulator phase transitions and proton-triggered hydrogen-induced electronic phase transitions. The technology provided by this invention enables the growth of thermodynamically metastable rare-earth nickel-based oxides on traditional group IV semiconductor substrates, such as silicon and germanium, thereby achieving compatibility of subsequent device fabrication processes with traditional silicon-based semiconductor technologies. The prepared materials have potential applications in neuronal devices, abrupt changeover thermistors, infrared camouflage, and laser weapon protection.

[0030] This invention, based on extensive and in-depth research, yields a method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials. By introducing a germanium dioxide high-oxygen-pressure phase, lattice-matched with the rare-earth nickel-based oxide, as a seed crystal or buffer layer, this invention enables the growth of rare-earth nickel-based oxides on traditional group IV semiconductor substrates, such as silicon and germanium. This allows for compatibility of subsequent device fabrication processes with traditional silicon-based semiconductor technologies, thereby enabling applications such as neuromorphic computing, abrupt thermistors, infrared camouflage, or laser weapon protection. Compared to traditional synthesis processes, this method overcomes the compatibility barrier between rare-earth nickel-based oxide electronic phase change materials and silicon-based technologies, and the functional properties can be synergistically controlled by the germanium dioxide high-oxygen-pressure phase structure and the rare-earth element composition. Attached Figure Description

[0031] Figure 1 The above is a grazing incidence X-ray diffraction pattern of NdNiO3 epitaxially grown on a Ge substrate with a high oxygen pressure phase of germanium dioxide, obtained using the method of this invention.

[0032] Figure 2 The resistance-temperature relationship curve is shown for the epitaxial growth of NdNiO3 on a Ge substrate with a high oxygen pressure phase of germanium dioxide introduced by the method of this invention.

[0033] Figure 3 This is a schematic diagram illustrating the principle of the 113-type rare earth nickel-based oxide polycrystalline film / germanium dioxide high oxygen pressure phase transition layer / single crystal germanium substrate synthesized by the method of the present invention.

[0034] Figure 4This is a schematic diagram illustrating the principle of the 113-type rare earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase coating structure synthesized by the method of this invention.

[0035] Figure 5 This is a schematic diagram illustrating the principle of the 113-type rare earth nickel-based oxide quasi-single crystal film / germanium dioxide high oxygen pressure phase transition layer / single crystal silicon substrate synthesized by the method of the present invention.

[0036] Figure 6 This is a schematic diagram illustrating the principle of the Ruddlesden-Popper type rare earth nickel-based oxide polycrystalline film / germanium dioxide high oxygen pressure phase transition layer / single crystal germanium substrate synthesized by the method of the present invention. Detailed Implementation

[0037] Unless otherwise specified, all raw materials used in this invention can be obtained commercially available or prepared according to conventional methods in the art. Unless otherwise defined or stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of skill in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to the methods of this invention.

[0038] Other aspects of the invention will be apparent to those skilled in the art from the disclosure herein.

[0039] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer.

[0040] Testing methods: The prepared materials were characterized using XRD and PPMS. The characterization methods were performed according to generally accepted standards in the field.

[0041] Example 1: A single-crystal Ge substrate was annealed at 550 °C under 10 MPa oxygen pressure for 2 h, resulting in a single-crystal germanium dioxide transition layer with a thickness of approximately 10 nm. Then, using nickel oxide and neodymium oxide as precursors and potassium chloride as molten salt, it was annealed at 800 °C under 7 MPa oxygen pressure for 24 h before being removed. The resulting NdNiO3 grazing incidence X-ray diffraction pattern is shown below. Figure 1 As shown, its resistance-temperature relationship is as follows: Figure 2 As shown, NdNiO3 films with a perovskite structure exhibit metal-insulator phase transition behavior at 187 K. The principle is as follows: Figure 3As shown, the lattice matching relationship between 113-type rare-earth nickel-based oxides and germanium dioxide high-oxygen-pressure phases is utilized to reduce the Gibbs formation free energy, thereby achieving non-uniform nucleation and growth of rare-earth nickel-based oxides. A discontinuous Pt electrode is deposited on the surface of an NdNiO3 thin film and reacted at 100 °C for 2 h in a mixed gas of hydrogen (10%) and argon (90%). After hydrogenation, its resistivity increases by three orders of magnitude. The NdNiO3 thin film prepared above is combined with a flexible blackbody background such as a carbon nanotube network. By applying an external electric field to control the spatial distribution of protons, the local infrared emission characteristics are altered, resulting in an erasable infrared coding device that can be used for optical anti-counterfeiting and smart displays.

[0042] Example 2: Using spherical commercial germanium dioxide microspheres with a particle size of 500 nm as the core material, the powder was annealed at 6 MPa oxygen pressure and 500 °C for 12 h. Then, using nickel oxide and neodymium oxide as precursors and potassium carbonate as molten salt, it was annealed at 7 MPa oxygen pressure and 800 °C for 24 h. After washing and drying, NdNiO3 / germanium dioxide high oxygen pressure phase-coated powder was obtained, with a phase transition temperature of 200 K. The principle is as follows: Figure 4 As shown, the surface of germanium dioxide seed crystals adsorbs 113-type rare earth oxides and nickel oxide precursors in the molten flux, and has a lattice-matching relationship with the fitted rare earth nickel-based oxides, thereby promoting the non-uniform nucleation and growth of rare earth nickel-based oxides on its surface to form a coating structure. The NdNiO3 / germanium dioxide high-oxygen-pressure phase-coated powder prepared above is dispersed on a PMN-PT substrate, and after being processed into a specific pattern by photolithography, it can identify changes in electrical signals caused by phase transitions after the application of an electrical pulse, and can be used in the field of intelligent digital technology.

[0043] Example 3: First, Ge was sputtered onto a single-crystal Si substrate by magnetron sputtering at a substrate temperature of 400 °C, an argon pressure of 1 Pa, a sputtering power of 85 W, and a sputtering time of 2 h. The substrate was then annealed at 500 °C under an ozone flow for 2 h to obtain a preferentially grown germanium dioxide high-oxygen-pressure phase transition layer. A precursor solution was prepared using gadolinium nitrate and nickel acetate as solutes and ethylene glycol methyl ether as a solvent. This solution was then spin-coated onto the Si substrate with the introduced germanium dioxide high-oxygen-pressure phase and reacted at 10 MPa oxygen pressure and 1000 °C for 24 h. The resulting 80 nm thick GdNiO3 quasi-single-crystal thin film had a phase transition temperature of 520 K. The principle is as follows: Figure 5 As shown, the germanium dioxide high-oxygen-pressure phase / silicon substrate heterojunction has a specific coherent matching relationship with the 113-type rare-earth nickel-based oxide, thereby reducing the Gibbs free energy of synthesis of the rare-earth nickel-based oxide and promoting its epitaxial growth. Applying an electric pulse to the prepared GdNiO3 quasi-single-crystal thin film triggers a metal-insulator transition. Utilizing the flexibility of the spike time in relation to the pulse intensity and duration, low-power biomimetic edge computing is achieved.

[0044] Example 4: Using germanium powder with a particle size of 50 nm as a precursor, germanium dioxide high-oxygen-pressure phase seed material was obtained after annealing at 500 °C for 12 h in an ozone atmosphere. A precursor solution was prepared using samarium nitrate, nickel nitrate, and PVP as solutes, and water and ethanol as solvents. The germanium dioxide high-oxygen-pressure phase seed material and the precursor solution were placed in a polytetrafluoroethylene reactor and reacted in a vacuum oven at 120 °C for 12 h. After washing and drying, it was calcined at 800 °C for 6 h to obtain SmNiO3 / germanium dioxide high-oxygen-pressure phase coated structure powder with a phase transition temperature of 410 K. The above-prepared SmNiO3 / germanium dioxide high-oxygen-pressure phase coated powder was dispersed in a flexible mica substrate and arranged in a specific structure to form a photonic crystal with a random dynamic optical resonant cavity structure. This allows for the control of infrared radiation transmittance and emissivity through metal-insulator transition within an atmospheric window.

[0045] Example 5: First, a germanium dioxide high-oxygen-pressure phase transition layer was grown on a single-crystal Ge substrate by magnetron sputtering. The substrate temperature was 500 °C, the background gas was argon (97%) and oxygen (3%), the pressure was 100 Pa, the sputtering power was 90 W, and the sputtering time was 2 h. Then, it was annealed at 500 °C and 5 MPa oxygen pressure for 5 h. La was then grown on the Ge substrate with the introduced germanium dioxide high-oxygen-pressure phase using pulsed laser technology. 1.99 Sr 0.01 NiO4 thin film, target material is La 1.99 Sr 0.01 A polycrystalline thin film with a thickness of 30 nm was obtained by using NiO4, substrate temperature 600 ℃, oxygen pressure 1 Pa, laser frequency 5 Hz, and deposition time 10 min. The principle is as follows: Figure 6 As shown, the germanium dioxide high-oxygen-pressure phase / germanium substrate heterojunction exhibits a specific coherent matching relationship with rare-earth nickel-based oxides possessing a Ruddlesden-Popper phase layered perovskite structure. This reduces the Gibbs free energy of synthesis of the metastable oxide, promoting its growth on the surface via heterogeneous nucleation. Placing this polycrystalline thin film in a 1 mol / L KOH solution resulted in a significant reduction in the oxygen evolution reaction overpotential, suggesting its potential as a catalyst for oxygen production via water electrolysis.

[0046] Example 6: Sputtering of Si by magnetron sputtering 0.3 Ge 0.7 Ge was sputtered onto a substrate at a temperature of 300 °C, an argon pressure of 0.5 Pa, a sputtering power of 70 W, and a sputtering time of 1.5 h. The substrate was then annealed at 600 °C for 1 h under an oxygen flow of 90 MPa to obtain a preferentially grown germanium dioxide high-oxygen-pressure phase polycrystalline layer. A precursor solution was prepared using gadolinium isooctanoate and nickel isooctanoate as solutes and xylene as solvent, and then spin-coated onto the Si substrate that introduced the germanium dioxide high-oxygen-pressure phase transition layer. 0.3 Ge 0.7On the substrate, after reacting at 12 MPa oxygen pressure and 900 °C for 36 h, the interface between GdNiO3 and the germanium dioxide high oxygen pressure phase was a Ruddlesden-Popper phase Gd2NiO4, which reduced the lattice mismatch caused by the reduction in rare earth ion radius. The resulting GdNiO3 polycrystalline thin film had a phase transition temperature of 500 K. The prepared GdNiO3 polycrystalline thin film underwent a metal-insulator transition on a very small timescale under the stimulation of an external electric field, electrochemical field, and cyclic temperature field, exhibiting non-volatile resistive switching functionality, and can be used in integrated memory devices.

[0047] Example 7: Sputtering of Si by magnetron sputtering 0.5 Ge 0.5 A germanium dioxide transition layer was grown on a substrate at a temperature of 600 °C. The background gas was a mixture of argon (97%) and oxygen (3%) at a pressure of 80 Pa. The sputtering power was 80 W, and the sputtering time was 1 h. The substrate was then annealed at 200 °C for 20 h using an ozone stream. Pr and Ni were used as targets, and magnetron co-sputtering was performed on Si substrates with a high-oxygen-pressure transition layer incorporating germanium dioxide. 0.5 Ge 0.5 A polycrystalline PrNiO3 film was grown on a substrate at a temperature of 500 °C. The background gas consisted of argon (97%) and oxygen (3%). The sputtering pressure was 20 Pa, the sputtering power was 100 W, and the sputtering time was 15 min. The phase transition temperature was 100 K. To fabricate a neuronal electronic device, a discontinuous Pt-Au electrode pair was introduced onto the surface of the PrNiO3 film. The film was then placed in a hydrogen (10%) and argon (90%) mixed gas mixture at 100 °C for reaction. A hydrogen ion gradient was established by controlling the hydrogenation time, and electrical pulses were applied to monitor the resistance changes in real time. An adaptive dynamic neuronal network was constructed to simulate the synaptic structure of human brain neurons, achieving low-energy in-memory computing functionality.

[0048] Example 8: A polycrystalline Ge substrate was annealed at 350 °C for 1 h under an ozone flow to obtain a preferentially grown germanium dioxide high-oxygen-pressure phase polycrystalline layer. A precursor solution was prepared using samarium nitrate and neodymium nitrate as solutes and ethylene glycol methyl ether as solvent, and then spin-coated onto the Ge substrate with the preferentially oriented germanium dioxide high-oxygen-pressure phase polycrystalline layer. The substrate was then annealed at 800 °C for 12 h under an ozone flow to obtain Nd2O3. 0.3 Sm 0.7 NiO3 thin films have a phase transition temperature of 300 K. To fabricate infrared camouflage devices near body temperature, a series of Nd... 0.3 Sm 0.7Infrared camouflage devices are obtained by arranging NiO3 thin films into a large-area array. When placed on human skin, the infrared emissivity changes abruptly after body temperature triggers an electronic phase transition. Under an infrared camera, the contrast of the image matches the environment, thus achieving the effect of infrared camouflage. A wide range of characteristic temperatures of the infrared camouflage devices can be controlled by changing the rare earth element composition.

[0049] Example 9: A single-crystal Ge substrate was annealed at 5 MPa oxygen pressure and 350 °C for 1 h. A precursor solution was prepared using yttrium isobutyrate and nickel isobutyrate as solutes and xylene as solvent, and then spin-coated onto the Ge substrate with a germanium dioxide high-oxygen-pressure phase. The substrate was then annealed at 10 MPa oxygen pressure and 600 °C for 24 h to obtain a YNiO3 thin film. The interface between YNiO3 and the germanium dioxide high-oxygen-pressure phase is a Ruddlesden-Popper phase (Y3Ni2O7), which reduces the lattice mismatch caused by the decrease in rare earth ion radius. As the atomic number of rare earth elements increases, the phase transition temperature gradually increases. By changing the rare earth element composition, a wide range of flexible control over the phase transition temperature can be achieved. Therefore, the abrupt changeover thermistor device prepared from this material can meet the needs of different application scenarios.

[0050] Example 10: First, Si was sputtered by magnetron sputtering 0.2 Ge 0.8 A germanium dioxide transition layer was grown on a substrate at a temperature of 300 °C. The background gas consisted of argon (97%) and oxygen (3%), with a pressure of 60 Pa, a sputtering power of 95 W, and a sputtering time of 1 h. The substrate was then annealed at 400 °C for 5 h using an ozone stream. The germanium dioxide high-oxygen-pressure phase was then introduced into the Si substrate using pulsed laser technology. 0.2 Ge 0.8 A ScNiO3 thin film was grown on a substrate with ScNiO3 as the target material. The substrate temperature was 700 °C, the oxygen pressure was 25 Pa, the laser frequency was 5 Hz, and the deposition time was 10 min. The phase transition temperature was 600 K. After absorbing microwaves and heating up, the temperature of the prepared ScNiO3 thin film rose above the phase transition temperature, transforming from an insulating phase to a metallic phase. This increased microwave reflectivity, making it suitable for intelligent microwave protection.

[0051] Example 11: A single-crystal Ge substrate was annealed at 400 °C under 8 MPa oxygen pressure for 2.5 h, and then annealed at 850 °C under 7 MPa oxygen pressure for 48 h using nickel oxide and dysprosium oxide as precursors and potassium chloride and lithium chloride as molten salts. The resulting DyNiO3 polycrystalline thin film had a phase transition temperature of 550 K. Further introduction of a dielectric layer and electrodes onto its surface can mimic the structure of organs such as insect antennae or reptile pits, achieving a thermal infrared signal electrical response function, which can be used for micro-fire hazard detection, nighttime detection, etc.

[0052] Example 12: Sputtering of Si by magnetron sputtering 0.9Ge 0.1 Ge was grown on a substrate at 400 °C, with an argon gas pressure of 10 Pa, a sputtering power of 120 W, and a sputtering time of 3 h, followed by annealing at 240 °C for 14 h using an ozone stream. A precursor solution was prepared using neodymium n-butyrate and nickel n-butyrate as solutes and toluene as solvent, and then spin-coated onto a Si substrate incorporating a high-oxygen-pressure phase of germanium dioxide. 0.9 Ge 0.1 On the substrate, an NdNiO3 thin film was obtained by annealing at 700 °C for 36 h under 8 MPa oxygen pressure. A discontinuous Pd electrode was introduced onto the surface of the NdNiO3 thin film and reacted at 100 °C for 3 h in a mixed gas of hydrogen (10%) and argon (90%). After hydrogenation, the resistivity increased by 7 orders of magnitude. Combined with the biomimetic design of the shark ampulla structure, it can be used for precise detection of seawater electric fields in deep-sea environments.

[0053] Example 13: A polycrystalline Ge substrate was annealed at 7 MPa oxygen pressure and 600 °C for 1.5 h, resulting in a germanium dioxide high-oxygen-pressure phase transition layer with a thickness of approximately 50 nm. Using nickel oxide, neodymium oxide, and samarium oxide as precursors, and sodium chloride as molten salt, the substrate was annealed at 7 MPa oxygen atmosphere and 800 °C for 6 h, yielding Nd... 0.5 Sm 0.5 NiO3 is a preferentially grown polycrystalline thin film with a phase transition temperature of 280 K. It is transparent under visible light irradiation, and Nd2O3 is transparent under laser irradiation. 0.5 Sm 0.5 The NiO3 thin film undergoes a metal-insulator transition, which leads to a significant decrease in its transmittance and a significant increase in its reflectivity, thereby achieving a protective effect against laser weapons.

[0054] Example 14: First, Ge was sputtered onto a Si wafer by magnetron sputtering at a substrate temperature of 250 °C, an argon pressure of 3 Pa, a sputtering power of 70 W, and a sputtering time of 1.5 h. Then, it was annealed at 350 °C under a 60 MPa oxygen atmosphere for 3 h to obtain a single-crystal germanium dioxide high-oxygen-pressure phase with a thickness of 200 nm. Using holmium oxide and nickel oxide as precursors, and potassium chloride and lithium chloride as molten salts, the reaction was carried out at 700 °C under a 10 MPa oxygen pressure for 12 h to obtain HoNiO3 as a quasi-single-crystal thin film with a phase transition temperature of 550 K. Based on its proton sensitivity, it can achieve contact-type responses to substances such as Lewis acids, mimicking the structure of interfacial receptors such as biological glutamate channels, to realize the active transport function of biomass. It can be used for biomimetic intelligent sensing, semi-permeable membrane valve control, etc.

[0055] Example 15: First, germanium dioxide was sputtered onto a SiC substrate by magnetron sputtering at a substrate temperature of 300 °C, a background gas of argon (97%) and oxygen (3%), a pressure of 20 Pa, a sputtering power of 100 W, and a sputtering time of 1 h, resulting in a single-crystal germanium dioxide high-oxygen-pressure phase with a thickness of 100 nm. A precursor solution was prepared using samarium nitrate and nickel acetate as solutes, ethylene glycol methyl ether as a solvent, and ethanolamine as a thickener, and spin-coated onto the SiC substrate with the introduced germanium dioxide high-oxygen-pressure phase. The reaction was carried out at 7 MPa oxygen pressure and 800 °C for 24 h, resulting in a polycrystalline SmNiO3 thin film with a phase transition temperature of 400 K. This material was incorporated into electrodes to fabricate micro-sensor chips and combined with biocompatible fabrics to create smart underwear, enabling 24-hour continuous monitoring and intelligent feedback of human body temperature, which can be used for reproductive cycle management, intelligent care, etc.

[0056] Example 16: A Ge wafer with a polished upper surface was annealed at 700 °C under 5 MPa oxygen pressure for 2.5 h, and then annealed at 500 °C under ozone flow for 0.5 h to obtain a single-crystal germanium dioxide transition layer with a thickness of 10 nm. A DyNiO3 thin film was grown on the Ge wafer with the introduced germanium dioxide high-oxygen-pressure phase using pulsed laser technology. The target material was DyNiO3, the substrate temperature was 600 °C, the oxygen pressure was 50 Pa, the laser frequency was 3 Hz, and the deposition time was 30 min. The resulting DyNiO3 thin film had a phase transition temperature of 520 K. This material can be introduced into electrodes and processed into specific superstructures to achieve surface plasmon resonance, thereby changing the transmittance and reflectance of electromagnetic waves in a specific wavelength range. It can be used for wide-range infrared camouflage, biomimetic photosensitive cells, etc.

[0057] Example 17: First, GeO2 was sputtered onto a single-crystal Ge substrate by magnetron sputtering at a substrate temperature of 300 °C, a background gas of argon (97%) and oxygen (3%), a pressure of 10 Pa, a sputtering power of 40 W, and a sputtering time of 15 min. Subsequently, it was annealed at 6 MPa oxygen pressure and 550 °C for 30 min to obtain a germanium dioxide high-oxygen-pressure phase transition layer with a thickness of 20 nm. Using europium nitrate and nickel nitrate as solutes, n-butyl acetate as solvent, and acetic anhydride as a drying agent, a precursor solution was prepared and spin-coated onto a single-crystal Si substrate with the introduced germanium dioxide high-oxygen-pressure phase. The reaction was carried out at 9 MPa oxygen pressure and 750 °C for 3 h, resulting in a polycrystalline thin film with preferred orientation and a phase transition temperature of 450 K. When the EuNiO3 film is covered on the engine cover of a drone, the heat during operation drives the EuNiO3 film to undergo a metal-insulator transition, which in turn causes a sudden change in its infrared emissivity. Under an infrared camera, the imaging contrast is consistent with the atmospheric background, thus achieving the function of infrared camouflage.

[0058] Example 18: First, a single-crystal Ge substrate was annealed at 650 °C for 1 h in an oxygen atmosphere of 10 MPa to obtain a single-crystal germanium dioxide high-oxygen-pressure phase with a thickness of 500 nm. Using thulium oxide and nickel oxide as precursors, and potassium chloride and lithium chloride as molten salts, the reaction was carried out at 600 °C for 4 h in an oxygen atmosphere of 15 MPa, resulting in a polycrystalline thin film with preferred orientation and a phase transition temperature of 600 K. A discontinuous Pt electrode was introduced onto the surface of the obtained thin film and placed on a polymer substrate. Without an applied electric field, the TmNiO3 thin film was in a high-emission state, exhibiting temperature contrast under an infrared camera; when a polarizing electric field was applied, the TmNiO3 thin film underwent a metal-insulator transition, transforming into a low-emission state, and the imaging contrast under an infrared camera was consistent with the atmospheric background, thus achieving an infrared camouflage effect.

[0059] Example 19: First, a polycrystalline Ge substrate was annealed at 800 °C for 30 min under an ozone flow to obtain a germanium dioxide high-oxygen-pressure phase transition layer with a thickness of 50 nm. An ErNiO3 thin film was grown on the polycrystalline Ge substrate with the introduced germanium dioxide high-oxygen-pressure phase using pulsed laser deposition (PLD). The target material was ErNiO3, the substrate temperature was 500 °C, the oxygen pressure was 70 Pa, the laser frequency was 2 Hz, and the deposition time was 1 h, resulting in a preferentially grown polycrystalline ErNiO3 thin film with a phase transition temperature of 570 K. A discontinuous Pt-Pd electrode pair was introduced onto the surface of the ErNiO3 thin film, and the film was reacted at 120 °C for 1.5 h in a mixed gas of hydrogen (20%) and nitrogen (80%). After hydrogenation, the resistivity increased by four orders of magnitude. In a proton-pre-doped state, this material can absorb protons from the solution environment or release protons to neutralize other ions in the solution environment after applying an electric field, achieving a resistivity-sensitive response to different solutes, which can be used in taste sensors.

[0060] Example 20: First, Ge was sputtered onto a Si wafer by magnetron sputtering at a substrate temperature of 350 °C, an argon pressure of 5 Pa, a sputtering power of 40 W, and a sputtering time of 0.5 h. Then, it was annealed at 150 °C under a 50 MPa oxygen atmosphere for 0.5 h to obtain a single-crystal germanium dioxide high-oxygen-pressure phase with a thickness of 10 nm. A precursor solution was prepared using lanthanum nitrate, neodymium nitrate, and nickel oxalate as solutes and ethylene glycol methyl ether as a solvent. This solution was spin-coated onto the Si wafer with the introduced germanium dioxide high-oxygen-pressure phase and reacted at 800 °C under a 5 MPa oxygen pressure for 3 h to obtain (La... 0.1 Nd 0.9 NiO3 is a quasi-single-crystal thin film grown epitaxially with a phase transition temperature of 100 K. After being processed into a specific pattern using laser direct writing technology, it is introduced into a comparator circuit and placed in a liquid nitrogen environment to trigger its metal-insulator transition. After detecting a drastic change in the electrical signal, it outputs an alarm message, which can therefore be used for deep space temperature alarm.

[0061] Example 21: Using germanium powder with a particle size of 80 nm as a precursor, germanium dioxide high-oxygen-pressure phase seed material was obtained after annealing at 500 °C for 12 h in an ozone atmosphere. A precursor solution was prepared using samarium nitrate, neodymium nitrate, nickel nitrate, and PVP as solutes and ethanol as solvent. The germanium dioxide high-oxygen-pressure phase seed material and the precursor solution were placed in a polytetrafluoroethylene reactor and reacted in a vacuum oven at 150 °C for 12 h. After washing and drying, it was calcined at 800 °C for 6 h to obtain Sm2Nd2Ni3O. 10 Germanium dioxide high-oxygen-pressure phase-coated powder. Utilizing the active oxygen physically adsorbed on the surface of this material, when placed in industrial wastewater, the polluting organic matter is oxidized into harmless inorganic substances, thereby achieving the function of low-cost wastewater purification.

[0062] Example 22: First, a germanium dioxide high-oxygen-pressure phase transition layer was grown on a single-crystal Si substrate by magnetron sputtering. The substrate temperature was 500 °C, the background gas was argon (97%) and oxygen (3%), the pressure was 100 Pa, the sputtering power was 90 W, and the sputtering time was 2 h. Then, it was annealed at 500 °C and 5 MPa oxygen pressure for 5 h. A precursor solution was prepared using neodymium nitrate, calcium nitrate, and nickel acetate as solutes and ethylene glycol methyl ether as solvent. This solution was spin-coated onto the Si substrate with the introduced germanium dioxide high-oxygen-pressure phase and reacted at 700 °C and 5 MPa oxygen pressure for 5 h to obtain Nd... 2.95 Ca 0.05 Ni2O7 material is a 40 nm thick quasi-single crystal thin film. After sputtering a transparent conductive oxide and a high-reflectivity metal functional layer on its surface, it can controllably collect and release indoor heat, thereby realizing an adjustable infrared radiation cooling function, which can be used for seasonal smart windows.

Claims

1. A method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials, characterized in that, By introducing a germanium dioxide high-oxygen-pressure phase that has a lattice-matching relationship with rare-earth nickel-based oxide electronic phase-change semiconductor materials in a thermodynamically metastable phase and is stable within the same high-oxygen-pressure range, a composite powder of rare-earth nickel-based oxide coated with germanium dioxide high-oxygen-pressure phase, a heterojunction of rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / germanium substrate, and a heterojunction of rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / silicon substrate can be effectively grown. Through the growth of the above rare-earth nickel-based oxide materials on silicon-based and germanium-based substrates, it is compatible with traditional silicon-based semiconductor microfabrication and device fabrication processes, thereby realizing applications such as neuron devices, abrupt change thermistors, infrared camouflage devices, and laser weapon protective layers.

2. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, The seed crystal or transition layer is a germanium dioxide high-oxygen-pressure phase, which has a similar lattice constant to rare-earth nickel-based oxides and is thermodynamically stable under the high-oxygen-pressure conditions required for the growth of rare-earth nickel-based oxides. It can directly encapsulate rare-earth nickel-based oxides onto germanium dioxide high-oxygen-pressure phase powder via high-oxygen-pressure molten salt reaction or hydrothermal reaction to prepare composite powders; or, first, a germanium dioxide high-oxygen-pressure phase transition layer is grown on a substrate, and then a rare-earth nickel-based oxide thin film precursor is deposited using spin coating, pulsed laser deposition, magnetron sputtering, or molten salt-assisted methods and annealed under high-oxygen-pressure conditions to prepare a rare-earth nickel-based oxide / germanium dioxide / substrate heterojunction thin film; or, first, Ge is grown on a substrate. The transition layer is annealed under high oxygen pressure (0.2-500 MPa) at 50-1500°C, oxidized under ozone atmosphere at 20-300°C, or oxidized by oxygen plasma to generate germanium dioxide high oxygen pressure phase. Then, rare earth nickel-based oxide thin film precursors are deposited using spin coating, pulsed laser deposition, magnetron sputtering, or molten salt assisted methods and annealed under high oxygen pressure to prepare rare earth nickel-based oxide / germanium dioxide / substrate heterojunction thin films. During the above oxidation process of germanium dioxide and germanium under high oxygen pressure and ozone, the stoichiometry and crystal structure at the interface between the generated germanium dioxide high oxygen pressure phase transition layer and the silicon substrate and rare earth nickel-based oxide can be adjusted to reduce lattice mismatch.

3. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, The synthesized rare-earth nickel-based oxide electronic phase change material has a 113-type twisted perovskite structure with the chemical formula ReNiO3, where Re is a single rare-earth element or a combination of multiple rare-earth elements other than lanthanum, including praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), yttrium (Y), and scandium (Sc). The electronic structure of the rare-earth nickel-based oxide can be controlled through the design of the rare-earth element composition, thereby adjusting its metal-insulator transition characteristics and hydrogen-induced electronic phase transition characteristics. The methods for synthesizing the rare-earth nickel-based oxide material include pulsed laser deposition, magnetron sputtering, hydrothermal methods, wet chemical spin coating, sol-gel methods, and molten salt methods. The orientation and thickness of the rare-earth nickel-based oxide electronic phase change material can be controlled by changing the synthesis process.

4. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, The fitted rare-earth nickel-based oxide electronic phase transition material also possesses a Ruddlesden-Popper phase layered perovskite structure, with the chemical formula (Re 1-x Ae x ) n+1 Ni n O 3n+1 Its structural features are a single-layer rock salt layer structure (Re 1-x Ae x O and n-layer perovskite structure (Re) 1-x Ae x The NiO3 element is arranged in alternating patterns; where Re represents a single rare earth element or a combination of multiple rare earth elements, including lanthanum (La), praseodymium (Pr), neodymium (Nd), and samarium (Sm); Ae represents an alkaline earth element; n is 1, 2, or 3, corresponding to (Re... 1-x Ae x )2NiO4、(Re 1-x Ae x )3Ni2O7、(Re 1- x Ae x )4Ni3O 10 .

5. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, To synthesize germanium dioxide high-oxygen-pressure phase powder coated with rare-earth nickel-based oxides, it is possible to obtain germanium dioxide high-oxygen-pressure phase by oxidizing commercial germanium dioxide as a precursor under high oxygen pressure or ozone atmosphere, or by oxidizing germanium powder as a precursor under high oxygen pressure or ozone atmosphere. The germanium dioxide high-oxygen-pressure phase powder has a curved surface shape including spherical, ellipsoidal, and cylindrical, with a size range of 0.1μm-1cm. The surface of the germanium dioxide high-oxygen-pressure phase powder has an adsorption effect on rare-earth element oxides and nickel element oxide precursors in molten flux, and has a lattice matching relationship with the fitted rare-earth nickel-based oxides, thereby promoting the non-uniform nucleation and growth of rare-earth nickel-based oxides on its surface to form a coating structure.

6. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, To synthesize a polycrystalline rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / germanium substrate heterojunction, the germanium substrate is first annealed under MPa-level high oxygen pressure, annealed in an ozone atmosphere, or oxidized by oxygen plasma to generate a germanium dioxide high-oxygen-pressure phase transition layer. By adjusting the thickness of the transition layer and the rare-earth nickel-based oxide growth process, the preferred orientation of the polycrystalline rare-earth nickel-based oxide film can be controlled, with a thickness range of 1-1000 nm; alternatively, glass, quartz, mica, silicon carbide, or Si can be used. 1-x Ge x The substrate replaces the germanium substrate, and germanium dioxide high-oxygen pressure phase is generated by plasma sputtering of germanium and further oxidation or by direct sputtering of oxygen plasma, so as to achieve non-uniform nucleation of rare earth nickel-based oxides on the surface of germanium dioxide high-oxygen pressure phase transition layer and growth into polycrystalline thin film with preferred orientation.

7. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, To synthesize a rare-earth nickel-based oxide quasi-single-crystal film / germanium dioxide high-oxygen-pressure / silicon substrate heterojunction, a germanium dioxide high-oxygen-pressure phase transition layer is obtained by plasma sputtering of germanium followed by further oxidation or by direct oxygen plasma sputtering. The germanium dioxide high-oxygen-pressure phase / silicon substrate heterojunction has a specific coherent matching relationship with the rare-earth nickel-based oxide, thereby reducing the Gibbs free energy of synthesis of the rare-earth nickel-based oxide and promoting its epitaxial growth. By adjusting the thickness of the transition layer and the rare-earth nickel-based oxide deposition process, the growth of a rare-earth nickel-based oxide quasi-single-crystal film can be achieved, with the transition layer thickness ranging from 1 to 1000 nm.

8. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, The prepared rare-earth nickel-based oxide / germanium dioxide high-oxygen-pressure phase / silicon substrate heterojunction can be connected to existing silicon-based semiconductor device processes to further fabricate proton-controlled neuron devices and strongly correlated electronic devices based on electric field and temperature-triggered phase transitions of metal insulators.

9. The method for growing germanium-based rare-earth nickel-based oxide electronic phase change materials as described in claim 1, characterized in that, Based on the abrupt change in infrared optical properties triggered by rare-earth nickel-based oxides at characteristic temperatures, the rare-earth nickel-based oxide / germanium dioxide high oxygen pressure / germanium substrate heterojunction grown using this method can be used to prepare laser weapon protective coatings and infrared camouflage devices.

Images