Preparation method, device and equipment of coated conductor of substrate and storage medium

Abstract

The invention relates to the technical field of superconduction, in particular to a preparation method, device and equipment of a coating conductor of a substrate and a storage medium. The method comprises the following steps: S1, acquiring related parameters of a target film, wherein the related parameters of the target film comprise at least one of material chemical compatibility, material expansion coefficient and lattice constant of the target film; s2, screening a buffer layer material meeting the conditions of the material chemical compatibility, the material expansion coefficient and / or the lattice constant of the target film from a material library; s3, acquiring the preset growth temperature and thickness of the target film; s4, determining target growth temperature and thickness corresponding to the target buffer layer material; and S5, preparing the coating conductor according to the target growth temperature and thickness. According to the method, the most suitable buffer layer can be selected, and the superconducting performance can be improved when the superconducting thin film is prepared on the metal base band with poor texture quality.

Description

Technical Field

[0001] The present invention relates to the field of superconducting technology, and particularly relates to a method, device, equipment and storage medium for preparing a coated conductor on a substrate. Background Art

[0002] Due to the ceramic nature of thin films and related weak connection characteristics, people have been searching for methods to grow high-quality or biaxially textured thin films for high-current devices. This effort has led to the practical application of technologies such as pulsed laser ablation (PLA) and ion beam assisted deposition (IBAD), as well as the development of buffer layer lamination technology, which has had a wide impact outside the field of high-temperature superconductivity. In this field, with the growth of oxide and heterostructure thin films, the superconductivity community has led the development of this field, which has completely changed the way people think about the practical application of oxides.

[0003] For the preparation of high-temperature superconducting thin films, the selection of substrate materials is more critical than other thin film processes and applications. High-temperature superconducting thin films are ceramic materials and must be deposited at high temperatures and sufficient oxygen partial pressures. Moreover, due to the anisotropy of most perovskite structures, only very high texture in all three-dimensional structures can produce high-performance high-temperature superconductors. Therefore, thin film deposition mainly focuses on epitaxy. The application of high-temperature superconducting thin films is carried out at low temperatures from 150K to 4K. Finally, if thin film technology is applied to technical products, not only physical aspects but also economic feasibility need to be considered.

[0004] When preparing high-temperature superconducting thin films on metal substrates with poor texture quality, one or more non-buffer layers need to be covered on the substrate to meet all the characteristics required for successful deposition of high-temperature superconducting thin films, while the substrate alone cannot be used. Therefore, the selection and preparation conditions of the buffer layer will have an important impact on the performance of the final high-temperature superconducting thin film. Therefore, a method capable of improving the superconducting performance of superconducting thin films on substrates needs to be developed. Summary of the Invention

[0005] In view of this, the present invention provides a method, device, equipment and storage medium for preparing a coated conductor on a substrate to improve the superconducting performance of superconducting thin films on the substrate.

[0006] The present application provides a method for preparing a coated conductor on a substrate, the method comprising:

[0007] Step S1: Obtain relevant parameters of the target thin film, the relevant parameters of the target thin film including at least one of the material chemical compatibility, material expansion coefficient and lattice constant of the target thin film;

[0008] Step S2: Screen buffer layer materials in the material library that meet the conditions of the material chemical compatibility, material expansion coefficient, and / or lattice constant of the target thin film as the target buffer layer materials;

[0009] Step S3: Obtain the preset growth temperature and preset thickness of the target thin film;

[0010] Step S4: Prepare target buffer layers on the substrate with different temperatures and different thicknesses using the target buffer layer materials, and prepare the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness to obtain coated conductor samples with different buffer layers; Test the superconducting properties of the coated conductor samples with different buffer layers respectively, and determine the target growth temperature and target thickness corresponding to the target buffer layer materials according to the superconducting properties;

[0011] Step S5: Prepare a target buffer layer on the substrate according to the target growth temperature and the target thickness of the target buffer layer material, and prepare the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness to obtain a coated conductor including the substrate, the target buffer layer, and the target thin film.

[0012] Optionally, in Step S2: The screening of materials in the material library that meet the conditions of the material chemical compatibility, material expansion coefficient, and / or lattice constant of the target thin film as the target buffer layer materials includes:

[0013] The target buffer layer materials screened in the material library meet at least one of the following conditions:

[0014] Do not chemically react with the material of the target thin film;

[0015] Within the allowable range of the material expansion coefficient of the target thin film;

[0016] The difference from the lattice constant of the target thin film is within the allowable range.

[0017] Optionally, the allowable range of the material expansion coefficient of the target thin film is: the difference from the material expansion coefficient of the target thin film does not exceed 1×10 -6 K -1 .

[0018] Optionally, the screening of buffer layer materials in the material library that meet the conditions of the material chemical compatibility, material expansion coefficient, and / or lattice constant of the target thin film as the target buffer layer materials includes:

[0019] In the material library, screen the first set of buffer layer materials that meet the conditions according to not chemically reacting with the material of the target thin film;

[0020] Screen a qualified second buffer layer material set from the first buffer layer material set according to whether it is within the range of the material expansion coefficient of the target thin film;

[0021] Screen a qualified buffer layer material from the second buffer layer material set according to whether the difference between the lattice constants of the target thin film is within the allowable range, and use it as the target buffer layer material.

[0022] Optionally, in the first buffer layer material set, according to whether the difference in the material expansion coefficient of the target thin film does not exceed 1×10 -6 K -1 , screen a qualified second buffer layer material set.

[0023] Optionally, screen the material with the closest lattice constant from the second buffer layer material set according to the lattice constant of the target thin film, and use it as the target buffer layer material.

[0024] Optionally, in step S4, use the target buffer layer material to prepare a target buffer layer on a substrate at different temperatures and different thicknesses, and prepare the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness to obtain a coated conductor sample with different buffer layers; respectively test the superconducting properties of the coated conductor samples with different buffer layers, and determine the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties, including:

[0025] Step S4-1: According to the preset growth temperature and preset thickness, while keeping the thickness of the target buffer layer at the first thickness, prepare a plurality of coated conductor samples at multiple sampling temperatures, and test the superconducting properties of the plurality of coated conductor samples. Screen the highest superconducting property from the multiple superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the target growth temperature;

[0026] Step S4-2: According to the preset growth temperature and preset thickness, while keeping the growth temperature of the target buffer layer at the first growth temperature, prepare a plurality of coated conductor samples among multiple sampling thickness values, and test the superconducting properties of the plurality of coated conductor samples. Screen the highest superconducting property from the multiple superconducting properties, and use the sampling thickness value corresponding to the highest superconducting property as the target thickness.

[0027] Optionally, step S3: Obtain the preset growth temperature and preset thickness of the target thin film, including:

[0028] Step S3-0: Obtain the preset growth temperature and preset thickness of the target buffer layer material;

[0029] Step S3-1: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the thickness of the target thin film at the second thickness, prepare multiple coated conductor samples at multiple sampling temperatures, test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature;

[0030] Step S3-2: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the growth temperature of the target thin film at the second growth temperature, prepare multiple coated conductor samples among multiple sampling thickness values, test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and use the sampling thickness value corresponding to the highest superconducting property as the preset thickness.

[0031] Optionally, the superconducting property includes the superconducting critical transition temperature;

[0032] Step S4: Test the superconducting properties of the coated conductor samples with different buffer layers respectively, and determine the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties, including:

[0033] Test the superconducting critical transition temperatures of the coated conductor samples with different buffer layers respectively, screen out the maximum superconducting critical transition temperature among all the superconducting critical transition temperatures, and use the growth temperature and thickness corresponding to the maximum superconducting critical transition temperature as the target growth temperature and target thickness.

[0034] Optionally, the materials in the material library include: single crystal substrate materials, metal substrate materials, and oxide substrate materials;

[0035] The single crystal substrate materials include: Si;

[0036] The metal substrate materials include: Ni, IBAD (ion beam assisted deposition material), and RABiTS (rolled assisted biaxially textured material);

[0037] The oxide substrate materials include: SrTiO3, MgO, CeO2, (yttria stabilized zirconia: ZrO2), or LaAlO3, etc. The oxide substrate is generally more stable than the metal substrate.

[0038] In addition, the present application also provides a coated conductor preparation device for a substrate, and the device includes:

[0039] An acquisition module, configured to acquire relevant parameters of a target thin film, where the relevant parameters of the target thin film include at least one of the material chemical compatibility of the target thin film, the material expansion coefficient, and the lattice constant of the target thin film;

[0040] A screening module, configured to screen a buffer layer material that meets the conditions of the material chemical compatibility of the target thin film, the material expansion coefficient, and / or the lattice constant of the target thin film in a material library as a target buffer layer material;

[0041] The acquisition module is further configured to acquire the preset growth temperature and the preset thickness of the target thin film;

[0042] A determination module, configured to respectively test the superconducting performance of the coating conductor samples prepared from the target buffer layer material at different temperatures and different thicknesses according to the preset growth temperature and the preset thickness, and determine the target growth temperature and the target thickness corresponding to the target buffer layer material according to the superconducting performance;

[0043] A generation module, configured to prepare a target buffer layer on a substrate according to the target growth temperature and the target thickness of the target buffer layer material, and prepare the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness, so as to obtain a coated conductor including the substrate, the target buffer layer, and the target thin film.

[0044] The present application further provides an electronic device, including a memory and a processor, where the memory is connected to the processor; computer instructions are stored in the memory, and the processor executes the computer instructions to execute the above-mentioned method for preparing a coated conductor on a substrate.

[0045] In addition, the present application further provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the above-mentioned method for preparing a coated conductor on a substrate.

[0046] By using the method of the present invention, the most suitable buffer layer can be selected, which can be used to prepare high-temperature superconducting thin films on metal substrates with poor texture quality. By optimizing the growth temperature and deposition thickness of the buffer layer and the thin film, the texture degree of the coated conductor is improved, and the superconducting performance including the superconducting critical transition temperature is improved. Description of the Drawings

[0047] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0048] Figure 1 A flow chart of a method for preparing a coated conductor of a substrate according to an embodiment of the present invention;

[0049] Figure 2 XRD test graphs of different materials of the embodiments of the present invention and XRD test comparison graphs of FST and CeO2;

[0050] Figure 3 It is a schematic diagram of superconducting performance test results of different buffer layers, FST film growth temperatures and thicknesses according to an embodiment of the present invention;

[0051] Figure 4 A schematic structural diagram of a device for preparing a coated conductor of a substrate according to an embodiment of the present invention;

[0052] Figure 5 The figure is a schematic diagram of the structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0054] The present invention provides a method for preparing a coated conductor of a substrate. It should be noted that Figure 1 The steps shown in the flowchart can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be performed in a different order than here. The specific steps are as follows:

[0055] Step S1: obtaining relevant parameters of a target film, wherein the relevant parameters of the target film include: at least one of the material chemical compatibility of the target film, the material expansion coefficient, and the lattice constant of the target film.

[0056] In this embodiment, the texture is poor. FeSe was prepared on IBAD (Ion Beam Assisted Deposition, IBAD, ion beam assisted deposition)-LMO (LnMnO3) substrate 0.5 Te 0.5 The target film is FeSe 0.5 Te0.5 (FST), obtain FeSe 0.5 Te 0.5 Relevant parameters of the thin film, including: FeSe 0.5 Te 0.5 The material chemical compatibility, material expansion coefficient of the thin film, and the lattice constant of the target thin film.

[0057] Step S2: Screen the buffer layer materials that meet the conditions of the material chemical compatibility, material expansion coefficient, and / or lattice constant of the target thin film in the material library as the target buffer layer materials.

[0058] In some alternative embodiments, the materials in the material library include one or more of single crystal substrate materials, metal substrate materials, and oxide substrate materials.

[0059] The single crystal substrate materials include Si; the metal substrate materials include: Ni, IBAD (ion beam assisted deposition material), and RABiTS (rolled assisted biaxially textured material); the oxide substrate materials include: SrTiO3, MgO, CeO2, YSZ, LaAlO3, etc.

[0060] In some alternative embodiments, step S2 specifically includes:

[0061] The target buffer layer materials screened in the material library meet at least one of the following conditions:

[0062] Do not chemically react with the materials of the target thin film;

[0063] Within the range of the material expansion coefficient of the target thin film;

[0064] The difference from the lattice constant of the target thin film is within the allowable range.

[0065] In this embodiment, step S2 specifically includes:

[0066] Screen the first set of qualified buffer layer materials that meet the conditions in the material library according to the non - chemical reaction between the materials and the materials of the target thin film;

[0067] Specifically in this embodiment, through experimental comparison, during the growth of the thin film, if it does not react with the buffer layer, it can be determined to be suitable as the first buffer layer material. The materials in the material library include: single crystal substrate materials, metal substrate materials, and oxide substrate materials; the single crystal substrate materials include Si; the metal substrate materials include Ni, IBAD, and RABiTS; the oxide substrate materials include SrTiO3, MgO, CeO2, (yttria-stabilized zirconia: ZrO2), or LaAlO3, etc. In principle, oxide substrates are more stable than metal substrates. For the applicability of substrate materials, it is very important not to interdiffuse with the high-temperature superconducting thin film. The chemical reaction between them will strongly affect the superconducting properties of the high-temperature superconducting thin film. Depending on the deposition method, the substrate must be widely inert under typical deposition conditions, which depends on the deposition method, such as an oxygen-rich atmosphere and a high temperature range between 650 °C and 850 °C. If a buffer layer that does not react with the high-temperature superconducting thin film is deposited on the bare substrate, interdiffusion can be avoided. Oxide buffer layers such as CeO2, MgO, Y2O3, or SrTiO3 are selected through chemical compatibility comparison to avoid the diffusion between the buffer layer and the thin film during the deposition of the thin film, thereby affecting the superconducting properties of the thin film.

[0068] In the first buffer layer material set, eligible second buffer layer material sets are screened according to whether they are within the range of the coefficient of thermal expansion of the target thin film material.

[0069] Specifically in this embodiment, materials with a relatively small difference in the coefficient of thermal expansion from the superconducting thin film (the difference does not exceed 1×10 -6 K -1 ) are selected as the buffer layer in the first buffer layer material set to avoid the thin film being subjected to stress from the substrate during growth and cracking, thereby affecting the superconducting properties of the thin film. The stress accumulates as the film thickness increases, and there is a critical thickness at which the stress causes the thin film to start cracking. During certain temperature changes, the thermal stress generated by the substrate on the surface of the thin film plays a dominant role. Therefore, materials with a large difference in thermal expansion from the thin film should not be used as the substrate. Table 1 shows the coefficient of thermal expansion α of the materials in the first buffer layer material set. The coefficient of thermal expansion of the FST thin film is (9 - 10)×10 -6 K -1 .

[0070] Table 1 Coefficient of thermal expansion of common substrates

[0071] <![CDATA[SrTiO3]]> <![CDATA[LaAlO3]]> <![CDATA[CeO2]]> <![CDATA[NdGaO3]]> YSZ MgO <![CDATA[Al2O3]]> <![CDATA[α(*10 -6 K -1 )]]> 9.4 10～13 9.2 9-11 11.4 14 9.4

[0072] In the second buffer layer material set, eligible buffer layer materials are screened according to whether the difference between the lattice constants of the target thin film is within the allowable range to be used as the target buffer layer material.

[0073] Specifically, in this embodiment, a suitable buffer layer material is selected from the second buffer layer material set based on the lattice matching degree between the buffer layer and the target thin film. For the deposition of high-temperature superconducting thin films with good superconducting properties (mainly high-temperature superconducting thin films with high critical current density), high texture should be exhibited both in and out of the plane of the thin film. As the grain boundary angle increases, the intergranular current drops very rapidly. For example, when the grain boundary angle is 5°, the J c value only reaches 10% of the maximum value. Only when the texture degree of the high-temperature superconducting thin film is as high as possible can the best performance be obtained. Therefore, epitaxial growth needs to be carried out on a single crystal or a substrate with a very high texture degree. The crystal structure on the surface of the substrate or the surface of the substrate buffer layer plays the most important role. Based on the X-ray diffraction pattern of the target superconducting thin film on the single crystal substrate, the in-plane lattice constant is calculated using Bragg's formula:

[0074] 2dsinθ = nλ

[0075] where λ is the X-ray wavelength, n is the diffraction order. By measuring the diffraction angle θ using X-rays with a known wavelength λ, the interplanar spacing d can be calculated, and thus the crystal structure can be analyzed. After screening, CeO2 is finally selected as the buffer layer. It is a key factor in improving the superconducting properties of the FeSe 0.5 Te 0.5 thin film because it is neither prone to interdiffusion with FST during the growth process of the superconducting thin film, nor has a thermal expansion coefficient similar to that of FST, and has a small stress effect on the thin film without causing the film to crack. Finally, its lattice constant is similar to that of FeSe 0.5 Te 0.5 thin film is quite comparable, and the lattice matching degree between the two is very high, so a FST thin film with a higher crystallization quality can be epitaxially grown on it, thereby improving the superconducting properties of the coated conductor.

[0076] Step S3: Obtain the preset growth temperature and preset thickness of the target thin film.

[0077] In some alternative embodiments, step S3 specifically includes:

[0078] Step S3-0: Obtain the preset growth temperature and preset thickness of the target buffer layer material.

[0079] For example, in this embodiment, the preset thickness of the target buffer layer, i.e., the CeO2 buffer layer, can be specifically set to 400 nm, and the preset growth temperature is 700 °C.

[0080] Step S3-1: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the thickness of the target thin film at the second thickness, prepare multiple coated conductor samples at multiple sampling temperatures. The preparation method is ion beam assisted deposition, and test the superconducting properties of the multiple coated conductor samples. Screen out the highest superconducting property from the multiple superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature.

[0081] In this embodiment, while keeping the thickness and growth temperature unchanged, the thickness of the target thin film FST is 150 nm. Then, prepare the target thin film FST at sampling temperatures of 400 °C, 425 °C, 450 °C, and 500 °C respectively. Test the superconducting properties of the multiple coated conductor samples. Screen out the highest superconducting property from the multiple superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature.

[0082] Step S3-2: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the growth temperature of the target thin film at the second growth temperature, prepare multiple coated conductor samples among multiple sampling thickness values. The preparation method is ion beam assisted deposition, and test the superconducting properties of the multiple coated conductor samples. Screen out the highest superconducting property from the multiple superconducting properties, and use the sampling thickness value corresponding to the highest superconducting property as the preset thickness.

[0083] In this embodiment, while keeping the thickness and growth temperature of the target buffer layer CeO2 buffer layer at the preset growth temperature and preset thickness unchanged, the growth temperature of the target thin film FST is 425 °C. Then, prepare the target thin film FST at sampling thicknesses of 100 nm, 150 nm, 200 nm, and 250 nm respectively. Test the superconducting properties of the multiple coated conductor samples. Screen out the highest superconducting property from the multiple superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature.

[0084] Step S4: Use the target buffer layer material to prepare the target buffer layer on the substrate at different temperatures and different thicknesses, and prepare the target thin film on the target buffer layer according to the preset growth temperature and preset thickness to obtain coated conductor samples with different buffer layers; respectively test the superconducting properties of the coated conductor samples with different buffer layers, and determine the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties.

[0085] In some optional embodiments, step S4 specifically includes:

[0086] Step S4-1: According to the preset growth temperature and preset thickness, while keeping the thickness of the target buffer layer at the first thickness, prepare multiple coated conductor samples at multiple sampling temperatures, test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and take the sampling temperature corresponding to the highest superconducting property as the target growth temperature.

[0087] In this embodiment, keep the thickness and growth temperature of the target thin film FST at the preset growth temperature and preset thickness. The thickness of the target buffer layer, the CeO2 buffer layer, is 400 nm. Then, prepare the CeO2 buffer layer at sampling temperatures of 650 °C, 700 °C, 750 °C, and 800 °C respectively. The preparation method is ion beam assisted deposition. Test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and take the sampling temperature corresponding to the highest superconducting property as the preset growth temperature.

[0088] Step S4-2: According to the preset growth temperature and preset thickness, while keeping the growth temperature of the target buffer layer at the first growth temperature, prepare multiple coated conductor samples among multiple sampling thickness values, test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and take the sampling thickness value corresponding to the highest superconducting property as the target thickness.

[0089] In this embodiment, keep the thickness and growth temperature of the target thin film FST at the preset growth temperature and preset thickness. The growth temperature of the target buffer layer, the CeO2 buffer layer, is 750 °C. Then, prepare the CeO2 buffer layer at sampling temperatures of 350 nm, 400 nm, 450 nm, and 500 nm respectively. The preparation method is ion beam assisted deposition. Test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting property from the multiple superconducting properties, and take the sampling temperature corresponding to the highest superconducting property as the preset growth temperature.

[0090] In some alternative embodiments, the method for testing the superconducting properties is specifically as follows: Test the superconducting critical transition temperatures of the coated conductor samples with different buffer layers respectively, screen out the maximum superconducting critical transition temperature among all the superconducting critical transition temperatures, and take the growth temperature and thickness corresponding to the maximum superconducting critical transition temperature as the target growth temperature and target thickness.

[0091] Table 2 shows the preparation conditions and their properties of some experimental samples prepared during the above screening process.

[0092] Table 2

[0093]

[0094] The finally obtained optimal treatment is that the thickness of the CeO2 buffer layer is 450 nm, the growth temperature is 750 °C, the thickness of the FST thin film is 200 nm, and the growth temperature is 450 °C. The superconducting critical transition temperature of the coated conductor prepared under this condition is the highest, which is 17.2 K.

[0095] Step S5: Prepare a target buffer layer on the substrate according to the target growth temperature and target thickness of the target buffer layer material, and prepare a target thin film on the target buffer layer according to the preset growth temperature and preset thickness, that is, a coated conductor including the substrate, the target buffer layer and the target thin film is obtained.

[0096] Then take the coated conductor prepared under this condition for testing, and the test results are as follows:

[0097] Figure 2 Shows FeSe 0.5 Te 0.5 XRD test results of the coated conductor: Figure 2 In (a), it is the XRD test pattern of different materials. Except for the diffraction peaks of the substrate and CeO2, only the (00l) diffraction peak of the FeSe 0.5 Te 0.5 thin film is detected, indicating that the thin film grows epitaxially along the c-axis without impurity phases. Compared with the FeSe 0.5 Te 0.5 thin film directly deposited on the IBAD-LMO template with poor texture (Δω FST ~3.357°, Δφ FST ~7.78°), the full width at half maximum (FWHM) of the rocking curve of the 002 peak of the thin film prepared by the present invention is smaller, as shown in (a), where Δω FST ~2.044°, which also indicates better out-of-plane crystallinity. This may also be because LMO with a smaller FWHM value (Δω LMO ~2.333°) and the CeO2 buffer layer (Δω CeO2 ~1.053°) are used. The out-of-plane lattice constant of the thin film is calculated through the position of the 001 peak Then according to the formula 1 / d 101 2 =1 / a 2 +1 / c 2 the in-plane lattice constant is obtained They are all greater than the lattice parameters of FST. Figure 2 In (b), it is the φ scan pattern of the 101 peak of FeSe 0.5 Te 0.5 and the 202 peak of CeO2. Obviously, only FeSe 0.5 Te 0.5Four each of FeSe and CeO2 were observed, and no other satellite peaks were observed, indicating that both have a structure with four-fold symmetry. In addition, FeSe 0.5 Te 0.5 The lattice of Te is offset by 45° relative to the lattice of CeO2 to achieve lattice matching, that is, FeSe 0.5 Te 0.5 (001)

[100] / / CeO2(001)

[110] , which is the same as the case of FeSe 0.5 Te 0.5 thin film grown on a CaF2(00l) substrate. As can be seen from the figure, the in-plane FWHM of FeSe 0.5 Te 0.5 and CeO2 are Δφ FST ~4.02° and Δφ CeO2 ~4.88°, respectively. It was found that compared with the in-plane misorientation degree Δφ LMO ~6.69° of the LMO baseband, the presence of the CeO2 buffer layer greatly reduced the out-of-plane and in-plane full-width at half-maximum values of the FeSe 0.5 Te 0.5 thin film, making the thin film have a good biaxial texture and higher crystallization quality. At the same time, it also shows that a high lattice matching degree between the thin film and the substrate is beneficial to the growth of high-quality thin films.

[0098] The FeSe 0.5 Te 0.5 thin film was subjected to R-T testing (10 - 300K), and the results are as Figure 3 shown, Figure 3 in which (a) is the detailed diagram (14 - 18K) of the superconducting transition process under two magnetic field directions, that is, H / / ab (left) and H / / c (right). The main factors that can determine the high and low of the thin film T c are the type of the substrate and the crystallization quality of the thin film, while the lattice constant of the thin film has little effect on T c . As can be seen from the above, the FeSe 0.5 Te 0.5 thin film deposited on CeO2 has better crystallization quality, and its out-of-plane and in-plane full-width at half-maximum are relatively small, so its is relatively high ~17K, and the transition width (ΔT c ) is also relatively narrow at 1.5K. In addition, when the magnetic field increases from 0 to 9T, T c will shift to a lower temperature, decreasing from 15.5K to 14.5K (H / / ab) and 14.1K (H / / c) respectively. An obvious feature of thermally activated vortex dynamics is the broadening of the superconducting transition in the presence of an external magnetic field. And the sensitivity of the superconductor to thermodynamic fluctuations can be evaluated by the Ginzburg number (Gi), which is defined as the minimum condensation energy within the coherent volume and Tc Ratio of lower activation energy (k B T c , where k B is the Boltzmann constant). Gi determines the width of the critical thermodynamic fluctuation region near T c (i.e., ΔT c ~G i T c ). The broadening of the R-T test curve in the H / / c direction is more obvious than that in the H / / ab direction, which is a typical characteristic of iron-based superconductors with high Gi values. Figure 3 In (b) of , the temperatures and magnetic fields corresponding to 90% and 10% of the normal-state resistivity values are selected respectively, and the curves of the upper critical field H c2 and the irreversible H irr of the thin film varying with temperature in two magnetic field directions are plotted. The H c2 curve of this thin film has a very high slope near T c , and |dμ0H c2 / dT| Tc ~11T K -1 when H / / c and |dμ0H c2 / dT| Tc ~18.3T K -1 when H / / ab. According to the Werthamer-Helfand-Hohenberg (WHH) formula, it can be deduced that this thin film has a very high upper critical field. This also indicates that the superconducting properties of the thin film grown under this condition are very good.

[0099] Specifically, in this embodiment, the preparation conditions are that the thickness of the CeO2 buffer layer is 450 nm, the growth temperature is 750 °C, the thickness of the FST thin film is 200 nm, and the growth temperature is 450 °C. The CeO2 buffer layer and the FST thin film are successively prepared on the LMO (LnMnO3) substrate to obtain a coated conductor with good superconducting properties including the LMO (LnMnO3) substrate, the CeO2 buffer layer, and the FST thin film.

[0100] In this embodiment, a coated conductor preparation device for the substrate is also provided. This device is used to implement the above embodiments and preferred implementation manners, and those that have been described will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that can achieve a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0101] This embodiment provides a coated conductor preparation device for the substrate, as Figure 4As shown, the device includes: an acquisition module 410, a screening module 420, a determination module 430, and a generation module 440. In addition, the device may further include more or fewer other modules, such as a storage module, which is not limited in this embodiment.

[0102] Among them, the acquisition module 410 is used to acquire relevant parameters of the target thin film. The relevant parameters of the target thin film include at least one of the material chemical compatibility, material expansion coefficient, and lattice constant of the target thin film.

[0103] The screening module 420 is used to screen buffer layer materials that meet the conditions of the material chemical compatibility, material expansion coefficient, and / or lattice constant of the target thin film in the material library as the target buffer layer materials.

[0104] The acquisition module 410 is further used to acquire the preset growth temperature and preset thickness of the target thin film.

[0105] The determination module 430 is used to respectively test the superconducting properties of the coated conductor samples prepared from the target buffer layer materials at different temperatures and different thicknesses according to the preset growth temperature and preset thickness, and determine the target growth temperature and target thickness corresponding to the target buffer layer materials based on the superconducting properties.

[0106] The generation module 440 is used to prepare the target buffer layer on the substrate according to the target growth temperature and target thickness of the target buffer layer material, and prepare the target thin film on the target buffer layer according to the preset growth temperature and preset thickness to obtain a coated conductor including the substrate, the target buffer layer, and the target thin film.

[0107] In some alternative embodiments, the screening module 420 is further specifically used to screen the target buffer layer materials in the material library that meet at least one of the following conditions:

[0108] Do not chemically react with the material of the target thin film;

[0109] Within the range of the material expansion coefficient of the target thin film;

[0110] The difference from the lattice constant of the target thin film is within the allowable range.

[0111] In some alternative embodiments, the materials in the material library include: single crystal substrate materials, metal substrate materials, oxide substrate materials; the single crystal substrate materials include Si; the metal substrate materials include: Ni, IBAD, and RABiTS; the oxide substrate materials include: SrTiO3, MgO, CeO2, YSZ, and LaAlO3.

[0112] In some alternative embodiments, the screening module 420 is further specifically configured to screen a set of first buffer layer materials that meet the conditions in the material library by determining whether the materials of the target thin film do not react;

[0113] In the set of first buffer layer materials, screen a set of second buffer layer materials that meet the conditions according to whether they are within the range of the coefficient of thermal expansion of the target thin film;

[0114] In the set of second buffer layer materials, screen the buffer layer materials that meet the conditions according to whether the difference between the lattice constants of the target thin film is within the allowable range, and use them as the target buffer layer materials.

[0115] In some alternative embodiments, the determination module 430 is specifically configured to, according to a preset growth temperature and a preset thickness, while maintaining the thickness of the target buffer layer at a first thickness, prepare a plurality of coated conductor samples at multiple sampling temperatures, test the superconducting properties of the plurality of coated conductor samples, screen out the highest superconducting property from the plurality of superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the target growth temperature. The determination module 430 is further specifically configured to, according to a preset growth temperature and a preset thickness, while maintaining the growth temperature of the target buffer layer at a first growth temperature, prepare a plurality of coated conductor samples among multiple sampling thickness values, test the superconducting properties of the plurality of coated conductor samples, screen out the highest superconducting property from the plurality of superconducting properties, and use the sampling thickness value corresponding to the highest superconducting property as the target thickness.

[0116] In some alternative embodiments, the superconducting property includes a superconducting critical transition temperature; the determination module 430 is configured to separately test the superconducting critical transition temperatures of the coated conductor samples with different buffer layers, screen out the maximum superconducting critical transition temperature among all the superconducting critical transition temperatures, and use the growth temperature and thickness corresponding to the maximum superconducting critical transition temperature as the target growth temperature and the target thickness.

[0117] In some alternative embodiments, the acquisition module 410 is further configured to acquire the preset growth temperature and the preset thickness of the target buffer layer material; according to the preset growth temperature and the preset thickness of the target buffer layer material, while maintaining the thickness of the target thin film at a second thickness, prepare a plurality of coated conductor samples at multiple sampling temperatures, test the superconducting properties of the plurality of coated conductor samples, screen out the highest superconducting property from the plurality of superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature. The acquisition module 410 is further configured to, according to the preset growth temperature and the preset thickness of the target buffer layer material, while maintaining the growth temperature of the target thin film at a second growth temperature, prepare a plurality of coated conductor samples among multiple sampling thickness values, test the superconducting properties of the plurality of coated conductor samples, screen out the highest superconducting property from the plurality of superconducting properties, and use the sampling thickness value corresponding to the highest superconducting property as the preset thickness.

[0118] The coating conductor preparation device for the substrate in this embodiment is presented in the form of functional units. Here, the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and a memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0119] An embodiment of the present invention also provides a computer device. Figure 5 FIG. 6 is a schematic structural diagram of a computer device provided by an alternative embodiment of the present invention. The computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including a high-speed interface and a low-speed interface. Each component communicates with each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface).

[0120] In some alternative embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a set of blade servers, or a multi-processor system). Figure 5 Take one processor 10 as an example.

[0121] The processor 10 can be a central processor, a network processor, or a combination thereof. Among them, the processor 10 can further include a hardware chip. The above hardware chip can be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The above programmable logic device can be a complex programmable logic device, a field programmable gate array, a generic array logic, or any combination thereof.

[0122] Among them, the memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method for preparing a coating conductor for the substrate shown in the above embodiment.

[0123] The memory 20 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created according to the use of the computer device and the like. In addition, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some alternative embodiments, the memory 20 may include a memory remotely disposed relative to the processor 10, and these remote memories may be connected to the computer device through a network. Examples of the above network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0124] The memory 20 may include volatile memory, such as random access memory. The memory may also include non-volatile memory, such as flash memory, a hard disk, or a solid-state drive. The memory 20 may also include a combination of the above types of memory.

[0125] The computer device further includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30, and the output device 40 may be connected through a bus or other means. Figure 5 Taking connection through a bus as an example.

[0126] The input device 30 may receive input digital or character information and generate key signal inputs related to user settings and function controls of the computer device, such as a touch screen, a keypad, a mouse, a trackpad, a touchpad, a pointing stick, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED), and a tactile feedback device (e.g., a vibration motor), etc. The above display device includes, but is not limited to, a liquid crystal display, a light-emitting diode, a display, and a plasma display. In some alternative embodiments, the display device may be a touch screen.

[0127] The computer device may further include a communication interface for the computer device to communicate with other devices or communication networks.

[0128] The embodiments of the present invention also provide a computer-readable storage medium. The methods according to the embodiments of the present invention may be implemented in hardware, firmware, or may be implemented as computer code recorded on a storage medium, or may be implemented as computer code originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and to be stored in a local storage medium, so that the methods described herein may be stored as such software processed on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware.

[0129] Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, a solid-state drive, etc.; further, the storage medium can also include a combination of the above-mentioned types of memories. It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component that can store or receive software or computer code, and when the software or computer code is accessed and executed by the computer, the processor or the hardware, the methods shown in the above embodiments are implemented.

[0130] Embodiments of the present application can also provide a computer program product, including computer program instructions, which cause the processor to execute the steps in the above method when the computer program instructions are run by the processor. Among them, the computer program product can be written in any combination of one or more programming languages to write program code for performing the operations of the embodiments of the present disclosure. The programming languages include object-oriented programming languages, such as Java, C++, etc., and also include conventional procedural programming languages, such as the "C" language or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, executed as an independent software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0131] The above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, and are not intended to limit them; although the embodiments of the present invention have been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a coated conductor of a substrate, characterized in that: The method comprises: Step S1: Acquire relevant parameters of a target film, wherein the relevant parameters of the target film include: at least one of the material chemical compatibility of the target film, the material expansion coefficient, and the lattice constant of the target film; Step S2: selecting a buffer layer material that meets the material chemical compatibility, material expansion coefficient and / or lattice constant of the target film in a material library as the target buffer layer material; Step S3: obtaining a preset growth temperature and a preset thickness of the target film; Step S4: preparing a target buffer layer on a substrate at different temperatures and different thicknesses using a target buffer layer material, and preparing the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness, to obtain coated conductor samples with different buffer layers; testing the superconducting properties of the coated conductor samples with different buffer layers respectively, and determining the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties; Step S5: preparing a target buffer layer on the substrate according to the target growth temperature and the target thickness of the target buffer layer material, and preparing the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness, to obtain a coated conductor comprising the substrate, the target buffer layer and the target thin film.

2. The method according to claim 1, characterized in that Step S2: screening a material that meets the material chemical compatibility, material expansion coefficient and / or lattice constant of the target film in the material library as the target buffer layer material includes: The target buffer layer material screened in the material library meets at least one of the following conditions: No chemical reaction occurs with the material of the target film; within the range of the material expansion coefficient of the target film; The difference between the lattice constant of the target film and that of the target film is within the allowable range.

3. The method according to claim 2, characterized in that The step of screening a buffer layer material that meets the material chemical compatibility, material expansion coefficient and / or lattice constant of the target film in a material library as the target buffer layer material includes: Screening a set of first buffer layer materials that meet the conditions in the material library by ensuring that the material of the target film does not chemically react with the material of the target film; Selecting a set of qualified second buffer layer materials from the first buffer layer material set according to whether the set of qualified second buffer layer materials is within the range of the material expansion coefficient of the target film; In the second buffer layer material set, a buffer layer material that meets the conditions is screened as the target buffer layer material according to whether the difference between the lattice constants of the target thin film is within an allowable range.

4. The method according to any one of claims 1 to 3, characterized in that: The step S4, using the target buffer layer material to prepare the target buffer layer on the substrate at different temperatures and different thicknesses, and preparing the target film on the target buffer layer according to the preset growth temperature and the preset thickness, to obtain coated conductor samples with different buffer layers; respectively testing the superconducting properties of the coated conductor samples with different buffer layers, and determining the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties, includes: Step S4-1: According to the preset growth temperature and the preset thickness, while maintaining the thickness of the target buffer layer at a first thickness, preparing a plurality of coated conductor samples at a plurality of sampling temperatures, and testing the superconducting properties of the plurality of coated conductor samples, selecting the highest superconducting property from the plurality of superconducting properties, and using the sampling temperature corresponding to the highest superconducting property as the target growth temperature; Step S4-2: According to the preset growth temperature and the preset thickness, while maintaining the growth temperature of the target buffer layer at the first growth temperature, prepare a plurality of coated conductor samples at a plurality of sampling thickness values, and test the superconducting properties of the plurality of coated conductor samples, screen out the highest superconducting performance from the plurality of superconducting properties, and use the sampling thickness value corresponding to the highest superconducting performance as the target thickness.

5. The method according to any one of claims 1 to 3, characterized in that: The step S3: obtaining the preset growth temperature and preset thickness of the target film, comprises: Step S3-0: obtaining a preset growth temperature and a preset thickness of a target buffer layer material; Step S3-1: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the thickness of the target film at a second thickness, prepare a plurality of coated conductor samples at a plurality of sampling temperatures, test the superconducting properties of the plurality of coated conductor samples, select the highest superconducting property from the plurality of superconducting properties, and use the sampling temperature corresponding to the highest superconducting property as the preset growth temperature; Step S3-2: According to the preset growth temperature and preset thickness of the target buffer layer material, while maintaining the growth temperature of the target film at the second growth temperature, prepare multiple coated conductor samples at multiple sampling thickness values, and test the superconducting properties of the multiple coated conductor samples, screen out the highest superconducting performance from the multiple superconducting properties, and use the sampling thickness value corresponding to the highest superconducting performance as the preset thickness.

6. The method according to any one of claims 1 to 3, characterized in that: The superconducting properties include superconducting critical transition temperature; Step S4: testing the superconducting properties of the coated conductor samples with different buffer layers respectively, and determining the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties, including: The superconducting critical transition temperatures of the coated conductor samples with different buffer layers are tested respectively, a maximum superconducting critical transition temperature is selected from all the superconducting critical transition temperatures, and the growth temperature and thickness corresponding to the maximum superconducting critical transition temperature are used as the target growth temperature and target thickness.

7. The method according to claim 1, characterized in that The materials in the material library include: single crystal base materials, metal base materials, and oxide base materials; The single crystal substrate material includes Si; Metal substrate materials include: Ni, IBAD and RABiTS; Oxide-based substrate materials include: SrTiO3, MgO, CeO2, YSZ and LaAlO3.

8. A device for preparing a coated conductor of a substrate, characterized in that: The device comprises: An acquisition module, used for acquiring relevant parameters of a target film, wherein the relevant parameters of the target film include: at least one of the material chemical compatibility of the target film, the material expansion coefficient and the lattice constant of the target film; A screening module, used to screen a buffer layer material that meets the conditions of the material chemical compatibility, material expansion coefficient and / or lattice constant of the target film in a material library as the target buffer layer material; The acquisition module is further used to acquire the preset growth temperature and preset thickness of the target film; A determination module, for the preset growth temperature and preset thickness, respectively testing the superconducting properties of coated conductor samples prepared by the target buffer layer material at different temperatures and different thicknesses, and determining the target growth temperature and target thickness corresponding to the target buffer layer material according to the superconducting properties; A generation module is used to prepare a target buffer layer on a substrate according to the target growth temperature and the target thickness of the target buffer layer material, and to prepare the target thin film on the target buffer layer according to the preset growth temperature and the preset thickness, so as to obtain a coated conductor comprising the substrate, the target buffer layer and the target thin film.

9. An electronic device, characterized in that: comprising a memory and a processor, wherein the memory and the processor are connected; The memory stores computer instructions, and the processor executes the method for preparing a coated conductor of a substrate according to any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method for preparing a coated conductor of a substrate according to any one of claims 1 to 7.

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