RU2629136C2 - Production method of high-temperature superconducting film on the quartz substrate - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: production method of high-temperature superconducting film on the amorphous quartz substrate involves applying of the three-layer coating into the pre-cleaned substrate surface. The first coating layer is formed from quartz with thickness 100-400 nm by magnetron spraying, the second layer is formed from zirconium dioxide, stabilized by yttrium with thickness 100-300 nm, the third layer is made of cerium dioxide with thickness 150-350 nm.

EFFECT: provision of the possibility to eliminate the cracking of the high-temperature superconducting film.

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Description

FIELD OF THE INVENTION

The invention relates to a cryogenic technique and can be used in the technology for producing a new generation of high-temperature superconducting (HTSC) wires (using flexible dielectric carriers) used both in high-current superconducting equipment (for example, superconducting transmission lines, current limiters), and in a low-current superconducting electronics (e.g., superconducting magnetic flux transformers and axial gradiometers for superconducting quantum magnetometers (SQUIDs), superconductors dyaschie information transmission line).

State of the art

Despite significant progress towards reducing the cost of high-temperature superconducting (HTSC) wires of the second generation and improving their characteristics, the problem of relatively high resistive losses on alternating current, especially in an external magnetic field (for example, Clem JR, Malozemoff A.R. Theory of ac loss in power transmission cables with second generation high temperature superconductor wires // Superconductor Science and Technology. 2010. Vol. 23, no. 3; Losses in Power Cables Made of 2G HTS Wires with Different Substrates / SS Fetisov, VV Zubko, AA Nosov et al. // Physics Procedia. 2012. Vol. 36, no. 0. P. 1319-1323). In general, the losses in the second-generation HTSC wires are composed of the hysteresis contribution due to magnetization reversal by an external and own magnetic field, eddy currents, and contact losses (as Loss analysis for superconducting generator armatures wound with subdivided Y-Ba-Cu-O coated tape / Charles E. Oberly, Larry Long, Gregory L. Rhoads, W. James Carr Jr // Cryogenics. - 2001. - Vol. 41, no. 2. - P. 117-124). Loss due to intrinsic magnetic field can be eliminated by using non-magnetic substrates and buffer layers. However, as shown in (Comparison of the AC losses of BSCCO and YBCO conductors by means of numerical analysis / Svetlomir Stavrev, Francesco Grilli, Bertrand Dutoit, Stephen P Ashworth // Superconductor Science and Technology. - 2005. - Vol. 18, no 10. - P. 1300), which determines the hysteresis loss, the ratio of the cross-sectional width of the superconducting layer to the height turns out to be a key factor affecting the value of losses at a nonzero frequency. For example, the losses for the second-generation Y-Ba-Cu-O (YBCO) tape strongly depend on the angle between the normal to the surface of the tape and the direction of the magnetic field lines: the losses in a parallel magnetic field are several times weaker than in a perpendicular one. Thus, in applications sensitive to energy dissipation, YBCO tapes are of little use. In particular, YBCO second-generation tapes still cannot replace their low-temperature counterparts for the implementation of superconducting magnetic flux transformers and axial gradiometers for superconducting quantum magnetometers (SQUIDs), information transmission lines, and connecting elements.

The solution to this problem may consist in creating wires based on dielectric substrates with a small aspect ratio. Substrates in the form of oxide fibers (sapphire, quartz, etc.) look very attractive from this point of view. Certain results were obtained using crystalline filaments as a substrate: recently, the properties of HTSC YBa ₂ Cu ₃ O _7-x (YBCO) films deposited on a sapphire faceted filament substrate (YBa2Cu3O7-δ films grown on faceted sapphire fiber / Y) were recently presented. Xu, N. Djeu, Z. Qian et al. // IEEE Transactions on Applied Superconductivity. - 2011 .-- Vol. 21, no. 3 PART 3. - P. 3281-3284). In this case, a flat facet of the substrate thread oriented in the r-plane and a buffer layer of cerium dioxide (CeO ₂ ) were used. The resulting samples showed good superconducting properties.

The following inventions are known in the art of applying HTSC films to dielectric substrates.

The method of depositing an oxide superconductor on a substrate (EP 0364068 (A2), John Joseph Talvacchio, Westinghouse Electric Corporation, US, 04/18/1990) involves the use of epitaxial deposition of superconducting oxide films with a thickness of 0.05- 2 microns on flat sapphire substrates.

In the invention, faceted ceramic fibers, tapes or strips and epitaxial devices therefrom (Faceted ceramic fibers, tapes or ribbons and epitaxial devices therefrom) (WO 2009042363 (A2), Ut-Battelle, Llc [US]; Amit Goyal, US - 2009 -04-02; US 8227082 (B2) - 2012-07-24), a crystalline object is described that includes a single-crystal ceramic filament, film or tape. A fiber, film or tape has at least one crystallographic face along their length, usually not less than one meter. In the case of sapphire, it is the R-, M-, C- or A-plane of the faces. Epitaxial objects, including superconducting ones, can be formed on a filament, film or tape. The epitaxial layer has a single epitaxial orientation. The thread, film or tape is a metal oxide selected from the group consisting of Al ₂ O _s , MgO, yttrium oxide stabilized zirconia (YSZ), SrTiO ₃ , NdGaO ₃ , LaAlO ₃ , YAlO ₃ and LSAT. The cross section of the aforementioned filament, film or tape is elliptical with flat faces at two wide ends, rhombohedral with four flat faces, hexagonal with six flat faces, square with four flat faces, elliptical with flat faces at two wide ends and additional minor faces on curved sides , or rectangular with four flat faces. The oxide buffer layer is selected from the group consisting of CeO ₂ , impurity CeO ₂ , perovoskite, impurity reminder, pyrochlore, impurity pyrochlore, fluorite, rock salt and spinel. It is indicated that this structure allows to reduce losses.

The application “Textured substrate tape and devices thereof” (US 2004003768 (A1), Amit Goyal, Ut-Battelle, Llc, 2004-01-08 (US 7087113 (B2)) describes a method forming a strictly biaxially textured substrate, which includes obtaining a deformed metal substrate, followed by heating above the secondary recrystallization temperature, and controlling the secondary recrystallization texture using either a thermal gradient and / or using a seed. The seed is selected to remove a stable texture below a predetermined rate Strictly biaxially textured substrate can be made in the form of a film having a length of 1 km or more. Epitaxial objects can be formed from films to use an epitaxial electromagnetic active layer. The electromagnetic active layer can be superconducting.

An improved method for obtaining superconducting films with lower losses due to more efficient vortex pinning with defects is presented in Superconductor films with improved flux pinning and reduced AC losses (US 7919435 (B2), Amit Goyal, Ut-Battelle, Llc, 05.05.2011) .

The invention "Magnesium-boride superconducting wires fabricated using thin high temperature fibers" (US 6946428 (B2), Rey Christopher Mark, 2005-09-20) presents a new approach to manufacture a low temperature superconducting (NTSC) wire or HTSC cable based on magnesium diboride (MgB ₂ ). This method uses a high temperature filament or film as a high performance substrate material. High-temperature filament-based substrates are low cost, round, light, non-magnetic, and capable of withstanding the high reaction temperatures necessary for the formation of the superconducting MgB ₂ phase without destruction.

JP 8148047 (A) Kitamura et al., 1996-06-07, describes the production of a superconducting film having excellent electrophysical characteristics on oxide filaments in a short time, in the application Manufacture of oxide superconducting wire material, JP 8148047 (A), 1996-06-07. single crystal. Here, in the solution obtained in the upper part of the Y ₂ O ₃ production crucible, by continuous immersion of the oxide fibers of a single crystal consisting of YSZ, or using other methods, such as the laser pedestal method for applying the YBa ₂ Cu ₃ O ₇ -Y phase, is formed on filament system of a superconducting film.

Thallium group superconducting wire (EP 0718897 (A1), NABATAME et. Al., 1996-06-26 describes a method for producing a crystal-oriented high-quality superconducting wire of the waist group having a high critical current density in the application. The superconducting film of the waist group is formed on oxide single crystal filaments with flat faces and polygonal sections. In the superconducting wire of the waist group, the c-axis of the superconducting film is oriented perpendicularly, while the a- and b-axes are oriented They are mounted parallel to the longitudinal axis of the aforementioned filament, respectively, resulting in a high-quality superconducting wire of the group with a critical current of 10 ⁵ A / cm ² or more at a temperature of 77K.

In the article "The films YBa ₂ Cu ₃ O _7-z grown on faceted sapphire fibers» (YBa ₂ Cu ₃ O _{7-z Films Grown on Faceted Sapphire Fiber} ) Yongli Xu a new approach to making thin faceted sapphire fiber as a substrate for the growth of thin YBCO films according to the technology of growing a support plate by laser heating. Single-crystal sapphire fibers 100 μm in diameter with two p-planar faces at the edges were grown. The process was tuned for the growth of the a-axis with very smooth p-planes at the edges by adjusting the speed, orientation and optimization of the process. The buffer layer was then sprayed by magnetron sputtering followed by a superconducting layer of a YBCO film. A critical current of more than 1 MA / cm ² was demonstrated at 77 K own field. Experimental results showed that fiber orientation and surface smoothness are critical for the characteristics of YBCO films and the desired parameters can be achieved using the presented technology.

In an advertising message http://www.sbir.gov/sbirsearch/detail/11587 "New YBCO Coated Filaments for Superconducting Magnets" (Novel YBCO Coated Filaments for Superconducting Magnets) on the 2010 contract work by Mr. Yongli Xu Dr DE-FG02-10ER85976, the following information is provided. AC losses are a serious problem for traditional conductors created on substrates from metal films. Cutting a wide film into small strips to reduce aspect ratio can minimize AC losses. However, serious technological limitations remain. At the same time, magnetic losses in the substrate and losses due to eddy currents are inevitable in the existing technology of coated conductors. Moreover, from an application point of view, buyers would rather need thin wires or several threads to combine in cables than wide films of coated conductors. Recently, the development of YBCO fibers on sapphire has begun, but due to the crystal structure and inconsistencies in the process of growing YBCO on sapphire, there are many restrictions (such as: surface utilization of the order of 50%, huge mismatch of 12%, restriction on the thickness of YBCO and growth orientation is less favorable ) Substrates of strontium titanate SrTiO ₃ , lanthanum aluminate LaAlO ₃ and / or zirconia stabilized with yttrium YSZ are excellent for spraying YBCO and can be grown in fiber form with an aspect ratio close to 1. The absence of a buffer or the possibility of using a very simple buffer significantly reduce the extremely high cost of the process today.

There is a final report from the Stanford University Materials Research Center (http://www.osti.gov/energycitations/servlets/purl/105033-Vd8rER/webviewable/105033.pdf) on the cultivation of superconducting fibers using laser heating “Growing high-temperature superconducting fibers with using a process with a reduced laser heating zone ”(Growth of high T _with superconducting fibers using a miniaturized laser-heated float zone process. Final technical report, January 15, 1989-December 31, 1994).

The domestic literature has not established sources in which the objects of this patent research would be considered in more detail or in detail than in the above foreign ones. In the invention RU 2450389, “Method for the formation of smooth ultrathin YBCO films of high conductivity” describes a method for forming by method of laser spraying nanofilms a complex metal oxide compound of YBa ₂ Cu ₃ O _7-x (YBCO) of high conductivity and can be used to create elements of nanoelectronics. The inventive method for forming smooth ultrathin YBCO films of high conductivity on a single crystal substrate by laser sputtering of a YBa ₂ Cu ₃ O _7-x target, form a film with a thickness of L = 5 ÷ 7 nm with a surface roughness of 1 ÷ 2 nm and a specific resistance of 0.8 ÷ 1.1⋅10 ^-6 Ohm⋅m, by exposing the target to laser radiation with a power density of P = 3⋅10 ⁸ ÷ 10 ⁸ W / cm ² , a wavelength of 1.06 μm, a pulse duration of 10-20 nsec and a repetition rate pulses of 10 Hz for a time t = 7 ÷ 10 s, with air pressure p = 50 ÷ 100 Pa, target temperature T = 600 ÷ 700 C, the substrate temperature T = 800 ÷ 840 ° C. The invention provides the creation of smooth ultrathin YBCO films on a single crystal substrate.

In the patent RU 2304827 C1 Igumnov et al., GOUVPO MSTU dated 08/20/2007 “Method for the formation of a high-temperature superconducting coating” describes a technology in which, before applying HTSC coating, the surface of the buffer sublayer is treated with ion-plasma etching to grade 10-13 and simultaneously dope with the surface of the buffer sublayer of 20-30% alloying additives of materials that increase the critical parameters of HTSC coatings.

A common drawback of all the solutions described with respect to the problems of creating third-generation HTSC wires is that the use of crystalline substrates requires a complex technology for growing faceted strands (the cross section of such a thread is a truncated circle) with the correct orientation of the crystal lattice relative to the face onto which it is sprayed HTSC material. The manufacture of such threads of sufficient length today is not possible.

On the other hand, amorphous fibers have long been used in fiber optic technology, their length can reach several kilometers, and the manufacturing technology does not cause difficulties. The fundamental difficulty in using quartz fibers lies in the large difference in the thermal expansion coefficients of amorphous quartz and YBCO (KTP YBCO is an order of magnitude higher), which leads to cracking of the VSTP film and the impossibility of using such conductors. The presented technique allows us to solve this technological problem and prevent cracking of the HTSC film.

SUMMARY OF THE INVENTION

The objective of the invention is to develop a new method for producing a thin (up to 500 nm) high-temperature (critical temperature not lower than 77.3 K) superconducting layer on a quartz substrate. The presented technique can be used to create technology for high-temperature superconducting (HTSC) wires on flexible amorphous quartz carrier threads.

The technical result of the invention is to obtain a high-quality coating. The inventive method allows the deposition of a thin layer of silicon dioxide (SiO2) on a substrate of amorphous quartz without cracking the sprayed next YBCO layer. Due to the large difference in the thermal expansion coefficients of YBCO and amorphous quartz, so far, YBCO sputtering led to cracking of the film with a crack period of the order of several microns, which made it impossible to use this material for overcurrent transport. The present invention solves this problem.

The problem is solved by the development of a method for producing a high-temperature superconducting film on an amorphous quartz substrate, including applying a three-layer coating to a pre-cleaned surface of the substrate, wherein the first coating layer is formed from quartz 100-400 nm thick by magnetron sputtering, the second layer is formed from yttrium stabilized zirconia 100-300 nm thick, the third from cerium dioxide 150-350 nm thick.

The first layer with a thickness of 100-400 nm can be formed by radio frequency magnetron sputtering using the following process parameters: power - 230-235 W, pressure Ar 5-5,2 510 ^-2 Torr, substrate temperature - 500-520 ° C, the deposition rate is 0.4-1 nm / s, the duration of deposition of the layer material is 400-410 s, the distance from the sample to the target is 12-12.5 cm.

The second layer with a thickness of 100-300 nm can be formed by pulsed laser deposition using an KrF gas excimer laser in accordance with the following regime: substrate temperature - 750-760 ° C, laser energy density - 1.89-1.9 J / cm ² , the number of pulses - 1950-2000, the pulse frequency - 5 Hz, the duration of the deposition - 6 min 30 s - 6 min 40 s, the distance from the target to the sample - 4.9-5 cm, the pressure in the chamber -1⋅10 ^{- 4} -1.1⋅10 ^-4 mbar.

The third layer with a thickness of 150-350 nm can be formed by pulsed laser deposition using an KrF gas excimer laser in an oxygen atmosphere without breaking the vacuum, in accordance with the following mode: substrate temperature - 720-730 ° C, laser energy density - 1, 89-1.9 J / cm ² , the number of pulses is 5950-6000, the pulse frequency is 10 Hz, the duration of the deposition is 10 min - 10 min 20 sec, the distance from the target to the sample is 4.9-5 cm, the oxygen pressure is 0.7-0.71 mbar.

After applying a three-layer coating, oxygen annealing is additionally carried out at an oxygen pressure of 800-810 mbar for 50-60 minutes.

In one embodiment of the invention, the preliminary surface cleaning of the substrate is carried out by immersing the substrate in a container with acetone for 10-12 minutes, then the substrate is placed in a vessel with isopropyl alcohol until the acetone dries (as quickly as possible), while cleaning the surface of the substrate is carried out in the container with isopropyl alcohol in an ultrasonic bath for 10-12 minutes, after which the substrate is dried with nitrogen for 10-15 seconds.

The problem is also solved by obtaining a high-temperature superconducting coating formed on an amorphous quartz substrate, including three layers, the first of which is made of quartz with a thickness of 100-400 nm, and placed directly on the surface of the quartz substrate, the second layer is placed on the first layer and formed from zirconia stabilized with yttrium 100-300 nm thick, the third layer, placed on the second layer, is made of cerium dioxide 150-350 nm thick.

The key difference between the proposed method and the known ones is the deposition of a thin (from 100 to 400 nm thick) SiO ₂ layer on a substrate before spraying a buffer layer of yttrium-stabilized zirconia (YSZ) and a superconducting layer YBa ₂ Cu ₃ O _7-x (YBCO). The coefficient of thermal expansion (CTE) of a thin quartz layer is higher than the CTE of a bulk sample, which allows stresses to relax in the SiO ₂ film. Moreover, the deposition of a SiO ₂ layer prevents the contact of impurities and surface defects of the substrate with the YSZ buffer layer, which also improves the quality of the buffer layer.

Brief Description of the Drawings

The invention is illustrated by drawings.

In FIG. 1 is a diagram of a pulsed laser deposition apparatus, in which the following elements are indicated by positions: 1 — vacuum chamber, 2 — sample, 3 — rotating targets, 4 — heated sample holder, 5 — Lambda Physik LPX 200 excimer laser, operating wavelength λ = 248 nm, 6 - focusing lens, 7 - stepper motor for changing targets, 8 - ablation torch, 9 - oxygen cylinder.

In FIG. 2 shows a diagram of an experimental sample created by the presented method, where: 10 is an amorphous quartz substrate 10 × 10 × 1 mm, 11 is a SiO ₂ layer sputtered by an rf magnetron, 12 is a YSZ buffer layer sputtered by laser deposition, 13 is a pulsed laser deposition of a layer of YBCO.

In FIG. Figure 3 presents a photograph from a scanning electron microscope of the surface of an experimental sample created by the presented method, showing the absence of cracks.

The implementation of the invention

A high temperature superconducting film is formed on the surface of an amorphous quartz substrate with a thickness of, for example, 0.5-1 mm. Before applying the high-temperature superconducting film, the surface of the amorphous quartz substrate is preliminarily cleaned by any method known in the art that provides the surface of the substrate of the 14th class of purity (surface roughness less than 50 nm). Then, a three-layer coating is formed on the cleaned surface, the first layer of which consists of quartz with a thickness of 100-400 nm, the second of zirconia stabilized with yttrium (YSZ) with a thickness of 100-300 nm, and the third of cerium dioxide with a thickness of 150-350 nm.

The first coating layer is formed from a quartz target by the method of magnetron sputtering (item 11 in FIG. 2), in particular, by the method of radio frequency magnetron sputtering, for example, using the Leybold LH Z400 apparatus. The presence of this layer avoids the occurrence of cracks with a period of the order of several microns during the formation of the YBCO layer (13 in FIG. 2). In this case, the formation of the first layer can be realized under the following conditions:

- Power - 230-235 W,

- Pressure Ar 5-5,2⋅10 ^-2 Torr,

- The temperature of the substrate is 500-520 ° C,

- The deposition rate of 0.4-1 nm / s,

- Duration of deposition - 400-410 s,

- The distance to the target is 12-12.5 cm.

The presence of a second layer (12 in FIG. 2) of zirconia allows you to create a texture for the epitaxial growth of the third layer of YBCO. The second layer is formed on the surface of the already formed first layer by the pulsed laser deposition method using an KrF gas excimer laser (FIG. 1), for example, of the brand Lambda Physik. In one embodiment, the following modes of forming the second layer may be proposed:

- The temperature of the substrate is 750-760 ° C,

- The laser energy density is 1.89-1.9 J / cm ² .

- The number of pulses - 1950-2000,

- Pulse frequency - 5 Hz,

- Duration of deposition - 6 min 30 s - 6 min 40 s,

- The distance from the target to the sample is 4.9-5 cm,

- pressure in the chamber - 1⋅10 -1,1⋅10 ^{-4 -4} mbar.

The third layer (13 in FIG. 2) of cerium dioxide is also formed by pulsed laser deposition on the surface of the formed second layer using an KrF gas excimer laser (FIG. 1) in an oxygen atmosphere without breaking the vacuum in accordance with the following mode:

- The temperature of the substrate is 720-730 ° C,

- The laser energy density is 1.89-1.9 J / cm ² ,

- The number of pulses - 5950-6000,

- Pulse frequency - 10 Hz,

- Duration of deposition - 10 min - 10 min 20 sec,

- The distance from the target to the sample is 4.9-5 cm,

- The oxygen pressure is 0.7-0.71 mbar.

After deposition of the third layer, oxygen annealing is carried out at an oxygen pressure of 800-810 mbar for 50-60 minutes.

In one embodiment of a particular embodiment of the invention, the preliminary surface cleaning of the substrate is carried out by immersing the substrate first in a container with acetone for 10-12 minutes, then in a vessel with isopropyl alcohol until the acetone dries (as quickly as possible), while cleaning the surface of the substrate is carried out in a container with isopropyl alcohol in an ultrasonic bath for 10-12 minutes, after which the substrate is dried with nitrogen for 10-15 seconds. After drying, a control inspection of the surface of the substrate is carried out using an optical microscope with a two-fold increase, and in the absence of streaks or other defects on the surface of the substrate, the formation of a high-temperature superconducting film is initiated. Otherwise, the surface is cleaned again.

Thus, for the implementation of the invention, the following equipment is required: an ultrasonic bath, an RF magnetron with the ability to control the temperature of the substrate, an apparatus for pulsed laser deposition (PLD) with the ability to supply oxygen to the vacuum chamber and control the temperature of the substrate (in FIG. 1 is an example implementation) as well as consumables - a quartz target for an RF magnetron, a yttrium barium oxide target of copper YBa ₂ Cu ₃ O _7-x for pulsed laser deposition, a zirconia target stabilized with yttrium oxide ZrO ₂ + Y ₂ O ₃ YBa ₂ Cu ₃ O _7-x for pulsed laser deposition, oxygen for supply to the vacuum chamber (9 in FIG. 1).

The inventive method was obtained an experimental sample with a high-quality coating, a photograph of which is presented in the photo. 3, confirming the achievement of the technical result.

The invention is illustrated by an example of a specific implementation

The obtained experimental sample contained a layer of SiO ₂ , 400 nm thick. The layer was sprayed using an RF magnetron with heating of the substrate to 500 ° C. The surface of the substrate was cleaned in an ultrasonic bath in a container with acetone for 10 minutes. Then, the substrate was placed in a vessel with isopropyl alcohol until the acetone dried, then it was placed in a container with isopropyl alcohol in an ultrasonic bath for 10 minutes, after which the sample was dried with nitrogen for 10 s. The first layer was sprayed using radio frequency magnetron sputtering in accordance with the following mode:

- Power - 230 W,

- Pressure Ar 5-10 ^-2 Torr,

- The temperature of the substrate is 500 C,

- Deposition rate - 0.4-1 nm / s,

- Duration of deposition - 400 s,

- The distance to the target is 12 cm,

- Film Thickness SiO ₂ - 200 nm.

The YSZ buffer layer was sprayed (12 in FIG. 2) by pulsed laser deposition using an KrF gas excimer laser (5 in FIG. 1) in accordance with the following mode:

- The temperature of the substrate (2 in FIG. 1) - 760 ° C,

- laser energy density - 1.9 J / cm ^2,

- The number of pulses - 2000,

- Pulse frequency - 5 Hz,

- Duration of deposition - 6 min 40 s,

- The distance from the target (3 in FIG. 1) to the sample (2 in FIG. 1) is 5 cm,

- Film thickness - 100 nm,

- The pressure in the chamber is 1-10 ^-4 mbar.

The third superconducting layer YBCO (12 in FIG. 2) was sprayed by pulsed laser deposition using an excimer laser (5 in FIG. 1) on a KrF gas mixture in an oxygen atmosphere without breaking the vacuum, in accordance with the following mode:

- The temperature of the substrate (2 in FIG. 1) - 730 ° C,

- The laser energy density is 1.9 J / cm ² ,

- The number of pulses - 6000,

- Pulse frequency - 10 Hz,

- Duration of deposition - 10 min,

- The distance from the target (3 in FIG. 1) to the sample (2 in FIG. 1) is 5 cm,

- Film thickness - 300 nm,

- The oxygen pressure is 0.7 mbar.

The obtained sample with sprayed layers was subjected to oxygen annealing at an oxygen pressure of 800 mbar for 1 hour.

As a result, a 300 nm thick YBCO layer without cracks was obtained on an amorphous quartz substrate. A snapshot of such a sample in a scanning electron microscope, showing the possibility of carrying out the invention, is shown in FIG. 3.

Claims (7)

1. A method of producing a high-temperature superconducting film on an amorphous quartz substrate, comprising applying a three-layer coating to a pre-cleaned surface of the substrate, wherein the first coating layer is formed from quartz 100-400 nm thick by magnetron sputtering, the second layer is formed from zirconia stabilized with yttrium 100 thickness 100 -300 nm, the third - from cerium dioxide with a thickness of 150-350 nm. 2. The method according to p. 1, characterized in that the preliminary cleaning of the surface of the substrate is carried out by immersing the substrate in a container with acetone for 10-12 minutes, then the substrate is placed in a vessel with isopropyl alcohol until the acetone dries (as quickly as possible), while cleaning the surface of the substrate is carried out in a container with isopropyl alcohol in an ultrasonic bath for 10-12 minutes, after which the substrate is dried with nitrogen for 10-15 seconds. 3. The method according to p. 1, characterized in that the first layer with a thickness of 100-400 nm is formed by the method of radio frequency magnetron sputtering using the following parameter values: power - 230-235 W, pressure Ar 5-5,2⋅10 ^-2 Torr, substrate temperature - 500-520 ° С, deposition rate - 0.4-1 nm / s, layer material deposition time - 400-410 s, distance from sample to target - 12-12.5 cm. 4. The method according to p. 1, characterized in that the second layer 100-300 nm thick is formed by pulsed laser deposition using an KrF gas excimer laser in accordance with the following mode: substrate temperature - 750-760 ° C, laser energy density - 1.89-1.9 J / cm ² , the number of pulses - 1950-2000, the pulse frequency - 5 Hz, the duration of the deposition - 6 min 30 s - 6 min 40 s, the distance from the target to the sample is 4.9-5 cm, pressure in the chamber - 1⋅10 ^-4 -1.1⋅10 ^-4 mbar 5. The method according to p. 1, characterized in that the third layer with a thickness of 150-350 nm is formed by pulsed laser deposition using an excimer laser on a KrF gas mixture in an oxygen atmosphere without breaking the vacuum, in accordance with the following mode: substrate temperature - 720- 730 ° С, laser energy density - 1.89-1.9 J / cm ² , number of pulses - 5950-6000, pulse frequency - 10 Hz, deposition time - 10 min - 10 min 20 sec, distance from target to sample - 4.9-5 cm, oxygen pressure 0.7-0.71 mbar. 6. The method according to p. 1, characterized in that after applying a three-layer coating carry out oxygen annealing at an oxygen pressure of 800-810 mbar for 50-60 minutes. 7. A high-temperature superconducting coating formed on an amorphous quartz substrate, including three layers, the first of which is made of quartz 100-400 nm thick and placed directly on the surface of the quartz substrate, the second layer is placed on the first layer and formed of yttrium stabilized zirconia 100-300 nm, the third layer, placed on the second layer, is made of cerium dioxide with a thickness of 150-350 nm.

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