High-temperature superconducting film microwave surface resistance local testing device and method

Abstract

The invention discloses a local testing device and method for microwave surface resistance of a high-temperature superconducting film, and relates to the technical field of electronics, the testing device comprises an Rs testing seat, a calibration assembly, a supporting plate and a sealing cavity, the Rs testing seat comprises an Rs testing cavity, a dielectric cylinder assembly and an annular metal film, the dielectric cylinder assembly is composed of a dielectric cylinder and a dielectric disc which are integrally formed and coaxially arranged, and the annular metal film is arranged on the dielectric cylinder assembly. The dielectric disc is located at the bottom of the dielectric cylinder, and the outer side of the lower surface of the dielectric disc is plated with an annular metal film. By plating the annular metal film on the lower surface of the dielectric disc of the dielectric cylinder assembly, the problem that a metal ring in an existing testing device is not coaxial and is prone to deformation is solved, continuous and stable testing conditions are provided for local testing of the microwave surface resistance of the high-temperature superconducting thin film, and high sensitivity and accuracy of testing are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of electronics, and in particular to a device and method for locally measuring the microwave surface resistance of a high-temperature superconducting thin film. Background Art

[0002] The microwave surface resistance Rs of a high-temperature superconducting (HTS) thin film in the liquid nitrogen temperature range is 2-3 orders of magnitude lower than that of a conventional good conductor. This low-loss characteristic enables high-temperature superconducting microwave passive devices based on HTS thin films to have excellent characteristics that cannot be compared with conventional devices in the microwave band. As one of the most important parameters of an HTS thin film, the value of the microwave surface resistance Rs is closely related to the performance of high-temperature superconducting microwave passive devices. Therefore, the measurement of the microwave surface resistance Rs of an HTS thin film is particularly important.

[0003] Currently, the most representative methods for Rs measurement are the quasi-optical cavity method and the two-terminal short-circuit method.

[0004] As Figure 1 shown, the quasi-optical cavity method utilizes the principle of optical focusing to focus electromagnetic energy on the HTS thin film to be measured. Moreover, the higher the operating frequency during the test, the smaller the focused area on the HTS thin film to be measured. Therefore, local Rs measurement of the HTS thin film to be measured can be achieved. The reported quasi-optical cavity method has a high operating frequency, generally above 100 GHz, and the experimental instruments are expensive and have low versatility.

[0005] As Figure 2 shown, the two-terminal short-circuit method uses the same test device to test two HTS thin films to be measured, and obtains the average microwave surface resistance of the two HTS thin films to be measured. To improve the test resolution of the two-terminal short-circuit method, the diameter of the cavity needs to be reduced, but the loss of the cavity wall will increase accordingly, reducing the Q value of the resonant cavity and the test sensitivity. When the cavity diameter is 10 mm, the Q value of the resonant cavity is better than 150000, and the simulation result of the cavity wall current is as Figure 3 shown. When the cavity diameter is 5 mm, the Q value of the resonant cavity is better than 30000, and the cavity wall current increases significantly. The simulation result is as Figure 4 shown. Therefore, the sensitivity of the two-terminal short-circuit method is not high. The reported two-terminal short-circuit method can distributively test a 3-inch superconducting thin film at a resonant frequency of 22 GHz, with a size resolution of a circular surface with a diameter of 16 mm and a Q value of about 5000-72000.

[0006] The existing Chinese patent CN201410610448.5, "Device and Method for Measuring the Microwave Surface Resistance Distribution of a High-Temperature Superconducting Thin Film", discloses a device for testing the local resistance of the microwave surface of a high-temperature superconducting thin film, as Figure 5As shown in the figure, a metal ring is provided and fixed on the inner wall of the shielding housing. However, it is difficult to ensure the coaxiality of the metal ring with the shielding housing and the dielectric column during fixation, and the operation is complex and the process is cumbersome. In addition, since the thickness range of the metal ring is only 0.1 mm - 0.5 mm, as part of the device, its thickness is very thin, and it is easy to deform during installation and is also prone to structural warping and deformation during use, resulting in poor contact between the superconducting thin film to be measured (or calibration component) and the metal ring, making it difficult to ensure the provision of continuous and stable test conditions and affecting the test accuracy. Summary of the Invention

[0007] Based on the above problems, the object of the present invention is to improve the existing device, solve the problems of non - coaxiality and easy deformation of the metal ring, provide continuous and stable test conditions for the local measurement of the microwave surface resistance of high - temperature superconducting thin films, and ensure the high sensitivity and accuracy of the test.

[0008] The technical solution adopted by the present invention is a local measurement device for the microwave surface resistance of high - temperature superconducting thin films, including an Rs test seat, a calibration component, a support plate, and a sealing cavity, where:

[0009] The Rs test seat includes an Rs test cavity, a dielectric column assembly, and a ring - shaped metal film. Input coupling structures and output coupling structures are symmetrically arranged on both sides of the Rs test cavity. The dielectric column assembly is composed of a dielectric cylinder and a dielectric disk that are integrally formed and coaxially arranged. The dielectric disk is located at the bottom of the dielectric cylinder. A pit is provided at the bottom end of the Rs test cavity, and the dielectric disk is embedded in the pit and fixedly connected to the Rs test cavity. The dielectric cylinder is located inside the Rs test cavity and is coaxial with the Rs test cavity. A ring - shaped metal film is plated on the outer part of the lower surface of the dielectric disk, and the ring - shaped metal film is concentric with the dielectric cylinder; the lower surface of the ring - shaped metal film and the bottom end surface of the Rs test cavity are in the same plane, jointly forming the test plane of the Rs test seat.

[0010] The HTS thin film to be measured is placed on the test plane of the Rs test seat and is supported and fastened by the support plate. The edge part of the support plate is detachably connected to the outer - extending part of the bottom end surface of the Rs test cavity.

[0011] The calibration component is detachably placed on the test plane of the Rs test seat.

[0012] The sealing cavity is detachably and hermetically fixed to the outer - extending part of the bottom end surface of the Rs test cavity and covers the calibration component, or the support plate and the HTS thin film to be measured.

[0013] Further, both the input coupling structure and the output coupling structure are coupling ring structures.

[0014] Further, the calibration component includes a calibration plate and a calibration seat. The edge part of the calibration plate is detachably connected to the outer extension part of the bottom end surface of the Rs test cavity. Except for the absence of an input coupling structure and an output coupling structure, the calibration seat has the same structure as the Rs test seat, that is, it also includes a cavity, a dielectric column assembly, and an annular metal film. However, there is no input coupling structure and output coupling structure on its cavity. Except that the outer diameter of the outer extension part of the cavity of the calibration seat is smaller than the outer diameter of the outer extension part of the Rs test cavity, the dimensions of the remaining parts are the same. The calibration seat and the Rs test seat are placed in an inverted symmetry with respect to the test plane, and the outer extension part of the calibration seat is detachably connected to the outer extension part of the bottom end surface of the Rs test cavity.

[0015] Further, the specific way of fixedly connecting the dielectric disk to the Rs test cavity is welding.

[0016] Further, the thickness range of the annular metal film is 300 nm to 1 μm, and the thickness range of the dielectric disk is 0.2 mm to 1 mm.

[0017] Further, the annular metal film uses an electroplated silver dielectric thin film.

[0018] Further, at least one exhaust through-hole is also provided on the dielectric disk, and the exhaust through-hole is located within the corresponding position range of the inner circle of the annular metal film. Since water vapor may condense in the liquid nitrogen test environment, damaging the superconducting thin film used in the test and reducing the Q value of the resonator cavity, the exhaust can be carried out through the exhaust through-hole.

[0019] The present invention also provides a method for local testing of the microwave surface resistance of a high-temperature superconducting thin film using the above test device. The method includes the following steps:

[0020] Step 1: Assemble the calibration plate with a microwave surface resistance of R S1 on the test plane of the Rs test seat, make the upper surface of the calibration plate closely adhere to the annular metal film of the Rs test seat, and after covering the calibration plate with a sealed cavity cover, place the test device in the working temperature of the HTS thin film to be measured, and measure its quality factor Q 01 ;

[0021] Step 2: Assemble the calibration seat with a microwave surface resistance of R S2 = 0 on the test plane of the Rs test seat, make the annular metal film of the calibration seat face and closely adhere to the annular metal film of the Rs test seat, and after covering the calibration seat with a sealed cavity cover, place the test device in the working temperature of the HTS thin film to be measured, and measure its quality factor Q 02 ;

[0022] Step 3: Assemble the HTS thin film to be measured on the test plane of the Rs test seat, make the upper surface of the HTS thin film to be measured closely adhere to the annular metal film of the Rs test seat, and use a support plate to support and fix the HTS thin film to be measured. After using a sealing cavity to cover the HTS thin film to be measured and the support plate, place the test device in the operating temperature of the HTS thin film to be measured, and measure its quality factor Q0;

[0023] Step 4: According to the formula

[0024]

[0025] Calculate the microwave surface resistance Rs of the corresponding part of the HTS thin film to be measured inside the inner circle of the annular metal film.

[0026] The beneficial effects of the present invention are as follows:

[0027] For the existing test device for measuring the microwave surface resistance distribution of high-temperature superconducting thin films, which is composed of a shielding shell, a dielectric column and a metal ring, it is difficult to ensure the coaxiality of the metal ring with the shielding shell and the dielectric column when the metal ring is fixed, and it is easy to deform during installation and is also prone to structural warping and deformation during use. The test device of the present invention improves the above-mentioned disadvantages:

[0028] Introduce a dielectric disc structure at the bottom end of the dielectric column in the existing structure, and coat an annular metal film on the lower surface of the dielectric disc. That is, the dielectric column assembly of the present invention is composed of an integrally formed and coaxial dielectric cylinder and dielectric disc. The annular metal film adopts a coating process, which ensures that the annular metal film is concentric with the dielectric cylinder and is not affected by the installation process, and will not deform, warp or shift during use, ensuring that there is always good contact between the superconducting thin film to be measured (or calibration component) and the annular metal film. That is, the present invention solves the problems of non-coaxiality and easy deformation of the metal ring in the existing structure, and can provide continuous and stable test conditions for the local test of the microwave surface resistance of high-temperature superconducting thin films, ensuring high sensitivity and accuracy of the test, and is especially suitable for the widely used 2-inch HTS thin films;

[0029] The annular metal film adopted by the present invention forms an integrated device with the test cavity, and the dielectric disc constitutes a perturbation, which does not affect the working mode and field distribution of the device;

[0030] The measured resolution diameter of the device of the present invention is completely determined by the inner diameter of the annular metal film, and the test cavity can be reused. For the same cavity, the device resolution can be changed by changing the inner diameter of the annular metal film;

[0031] Compared with the quasi-optical cavity test method, the present invention has high versatility; compared with the two-terminal short-circuit test method, the present invention improves the test resolution from 16 mm to 4.5 mm, can realize the local precise test of the HTS thin film to be measured, and has a wider application. Description of the Drawings

[0032] Figure 1 It is a structural diagram of the device for the existing quasi-optical cavity test method;

[0033] Figure 2 It is a structural diagram of the device for the existing double-end short-circuit test method;

[0034] Figure 3 It is a simulation result diagram of the cavity wall current when the cavity wall diameter is 10 mm in the double-end short-circuit test method;

[0035] Figure 4 It is a simulation result diagram of the cavity wall current when the cavity wall diameter is 5 mm in the double-end short-circuit test method;

[0036] Figure 5 It is a schematic structural diagram of an existing high-temperature superconducting thin film microwave surface resistance distribution test device;

[0037] Figure 6 It is a sectional view of the Rs test seat in the test device of Embodiment 1 of the present invention;

[0038] Figure 7 It is a sectional view of the test device of Embodiment 1 of the present invention after loading the HTS thin film to be measured;

[0039] Figure 8 It is a sectional view of the test device of Embodiment 1 of the present invention after loading the calibration plate;

[0040] Figure 9 It is a sectional view of the test device of Embodiment 1 of the present invention after loading the calibration seat;

[0041] Figure 10 It is a simulation three-dimensional model of the test device of Embodiment 1 of the present invention;

[0042] Figure 11 It is a simulation diagram of the electromagnetic field distribution of the existing metal ring structure test device;

[0043] Figure 12 It is a simulation diagram of the electromagnetic field distribution of the device of Embodiment 1 of the present invention. Detailed implementation manners

[0044] In order to be able to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0045] Embodiment 1

[0046] Figures 6 to 9 A specific implementation manner of the high-temperature superconducting thin film microwave surface resistance local test device of the present invention is shown, including an Rs test seat, a calibration component, a support plate 5, and a sealed cavity 6, wherein:

[0047] The Rs test socket includes an Rs test cavity 1, a dielectric column assembly 2, and a ring-shaped metal film 3. Input coupling structures 10 and output coupling structures 11 are symmetrically arranged on both sides of the Rs test cavity 1. Both the input coupling structures 10 and the output coupling structures 11 are coupling ring structures. The dielectric column assembly 2 is composed of a dielectric cylinder 201 and a dielectric disc 202 that are integrally formed and coaxially arranged. The dielectric disc 202 is located at the bottom of the dielectric cylinder 201. The main body of the Rs test cavity 1 is a hollow cylinder structure, with its top end closed and its bottom end open. The bottom end also has an outwardly extending extension part. A pit is also opened at the bottom end of the Rs test cavity 1. The dielectric disc 202 is embedded in the pit and fixedly connected to the Rs test cavity 1 by welding. The dielectric cylinder 201 is located inside the Rs test cavity 1 and is coaxial with the Rs test cavity 1. A ring-shaped metal film 3 is plated on the outer side part of the lower surface of the dielectric disc 202. The ring-shaped metal film 3 is concentric with the dielectric cylinder 201; the lower surface of the ring-shaped metal film 3 is in the same plane as the bottom end face of the Rs test cavity 1, jointly constituting the test plane of the Rs test socket; two exhaust through holes 9 are also opened on the dielectric disc 202, and the exhaust through holes 9 are located within the corresponding position range of the inner circle of the ring-shaped metal film 3;

[0048] The HTS thin film 4 to be measured is placed on the test plane of the Rs test socket and is supported and fastened by a support plate 5. The edge part of the support plate 5 is detachably connected to the extension part of the bottom end face of the Rs test cavity 1;

[0049] The calibration assembly is detachably placed on the test plane of the Rs test socket;

[0050] The calibration assembly specifically includes a calibration plate 7 and a calibration socket 8. The edge part of the calibration plate 7 is detachably connected to the extension part of the bottom end face of the Rs test cavity 1. Except for the absence of input coupling structures and output coupling structures, the calibration socket 8 has the same structure as the Rs test socket, that is, it also includes a cavity, a dielectric column assembly, and a ring-shaped metal film. Two exhaust through holes are also correspondingly opened on the dielectric disc of the dielectric column assembly of the calibration socket 8, but there are no input coupling structures and output coupling structures on its cavity. Except that the outer diameter of the extension part of the cavity of the calibration socket 8 is smaller than the outer diameter of the extension part of the Rs test cavity 1, the dimensions of the remaining parts are the same; the calibration socket 8 and the Rs test socket are placed in an inverted and symmetric manner with respect to the test plane, and the extension part of the calibration socket 8 is detachably connected to the extension part of the bottom end face of the Rs test cavity 1;

[0051] The sealing cavity 6 is detachably and hermetically fixed to the extension part of the bottom end face of the Rs test cavity 1 and covers the calibration assembly, or the support plate 5 and the HTS thin film 4 to be measured.

[0052] The specific manner in which the support plate 5, calibration plate 7, calibration seat 8, and sealing cavity 6 are detachably connected to the extended part of the bottom end surface of the Rs test cavity 1 can adopt conventional connection methods, such as screw connection, snap connection, etc.

[0053] In this embodiment, for the dielectric resonator in the TE 012 mode, using its boundary conditions and through Maxwell equation analysis, the resonant frequency of the dielectric resonator is calculated to be 37 GHz. The specific physical dimensions of each component are as follows:

[0054] The Rs test cavity 1 is prepared from brass silver-plated material. The outer diameter of the hollow cylindrical structure of its main body is 45 mm, and the height is 17 mm; the dielectric column assembly 2 is made of a high-Q material with low loss and high dielectric constant, specifically sapphire. Since the dielectric disk 202 is made of sapphire material, it has high hardness and is of an integral structure. Compared with the existing test device with a metal ring structure, the metal ring is generally made of copper material, and the structure of the present invention is not easily deformed; the diameter of the dielectric cylinder 201 is 2.6 mm, and the height is 5.2 mm; the thickness of the dielectric disk 202 is 1 mm; the annular metal film 3 is prepared by electroplating silver, its inner diameter is 4.2 mm, and the thickness is 1 μm.

[0055] The planar size of the HTS thin film 4 to be measured is 2 inches, and the thickness is 500 nm.

[0056] In this embodiment, the relationship between the unloaded quality factor Q0 of the dielectric resonator formed by the HTS thin film 4 to be measured and the microwave surface resistance Rs of the HTS thin film 4 to be measured is as follows:

[0057]

[0058] In the formula, both A and B are constants independent of the microwave surface resistance Rs of the HTS thin film 4 to be measured, and are determined by the measurement method.

[0059] The usage method of the device in this embodiment is as follows:

[0060] When loading the HTS thin film to be measured: Place the HTS thin film 4 to be measured on the test plane of the Rs test seat and fasten it with the detachable support plate 5, so that the upper surface of the HTS thin film 4 is closely attached to the annular metal film 3 of the Rs test seat. The HTS thin film 4 and the Rs test seat form a dielectric resonator in the TE 012 mode. Then, use the sealing cavity 6 to cover the support plate 5 and the HTS thin film 4 to be measured, and connect and fix the sealing cavity 6 to the extended part of the bottom end surface of the Rs test cavity 1.

[0061] When loading the calibration plate 7: Assemble the calibration plate 7 on the test plane of the Rs test seat, make the upper surface of the calibration plate 7 closely adhere to the annular metal film 3 of the Rs test seat, connect and fix the edge part of the calibration plate 7 to the extended part of the bottom end surface of the Rs test cavity 1, and then cover the calibration plate 7 with the sealing cavity 6, and connect and fix the sealing cavity 6 to the extended part of the bottom end surface of the Rs test cavity 1.

[0062] When loading the calibration seat 8: Assemble the calibration seat 8 on the test plane of the Rs test seat, make the annular metal film of the calibration seat 8 face and closely adhere to the annular metal film 3 of the Rs test seat, connect and fix the extended part of the calibration seat 8 to the extended part of the bottom end surface of the Rs test cavity 1, and then cover the calibration seat 8 with the sealing cavity 6, and connect and fix the sealing cavity 6 to the extended part of the bottom end surface of the Rs test cavity 1.

[0063] Example 2

[0064] A method for local testing of the microwave surface resistance of a high-temperature superconducting thin film using the testing device described in Example 1 includes the following steps:

[0065] Step 1. Assemble the calibration plate 7 with a microwave surface resistance of R S1 on the test plane of the Rs test seat, make the upper surface of the calibration plate 7 closely adhere to the annular metal film 3 of the Rs test seat, and after covering the calibration plate 7 with the sealing cavity 6 in a sealed manner, place the testing device at the working temperature of the HTS thin film 4 to be measured, and measure its quality factor Q 01 ;

[0066] Step 2. Assemble the calibration seat 8 with a microwave surface resistance of R S2 = 0 on the test plane of the Rs test seat, make the annular metal film of the calibration seat 8 face and closely adhere to the annular metal film 3 of the Rs test seat, and after covering the calibration seat 8 with the sealing cavity 6 in a sealed manner, place the testing device at the working temperature of the HTS thin film 4 to be measured, and measure its quality factor Q 02 ;

[0067] Step 3. Assemble the HTS thin film 4 to be measured on the test plane of the Rs test seat, make the upper surface of the HTS thin film 4 to be measured closely adhere to the annular metal film 3 of the Rs test seat, and use the support plate 5 to support and fix the HTS thin film 4 to be measured. After covering the HTS thin film 4 to be measured and the support plate 5 with the sealing cavity 6 in a sealed manner, place the testing device at the working temperature of the HTS thin film 4 to be measured, and measure its quality factor Q0;

[0068] Step 4. According to the formula

[0069]

[0070] calculate the microwave surface resistance Rs of the corresponding part of the HTS thin film 4 to be measured inside the inner circle of the annular metal film 3.

[0071] Due to the presence of the annular metal film 3, the electromagnetic field energy acting on the HTS thin film 4 to be measured is only the area size of the inner circle of the annular metal film 3. Therefore, the finally obtained test result is the microwave surface resistance of the HTS thin film part corresponding to the inner circle of the annular metal film 3.

[0072] Using the device and method described in this embodiment, with HTS thin films having nominal values of microwave surface resistance Rs of 0.250 mΩ, 0.300 mΩ, and 0.350 mΩ respectively as the HTS thin films to be measured, the simulation results of the dielectric resonator formed by loading the HTS thin films to be measured are shown in the following table. It can be seen that the relative deviation between the calculated value and the nominal value of the microwave surface resistance of the HTS thin film to be measured is very small (both within 4%), indicating that the test accuracy of the device described in this embodiment is very high.

[0073]

[0074] The device and method of the present invention have prominent advantages compared with the test methods in two international standards. Specifically: the resonant frequency of the quasi-optical cavity test method is 145 GHz, and the operating frequency of the device described in Embodiment 1 is only 37 GHz, improving the versatility; at a resonant frequency of 22 GHz, the Q value of the double-end short-circuit test method is 5000 to 72000, and the resolution is 16 mm, while the resolution of the device described in Embodiment 1 of the present invention reaches 4.5 mm, greatly improving the resolution. The simulation three-dimensional model of the test device in Embodiment 1 of the present invention is as Figure 10 shown.

[0075] Figure 11 is the simulation diagram of the electromagnetic field distribution of the existing test device with a metal ring structure, Figure 12 is the simulation diagram of the electromagnetic field distribution of the device in Embodiment 1 of the present invention. From the comparison of the electromagnetic field distributions of the two diagrams, it shows that the electromagnetic field distribution of the structure of the present invention has not changed and meets the test requirements.

Claims

1. A local test device for microwave surface resistance of high-temperature superconducting thin films, characterized in that: It comprises an Rs test seat, a calibration component, a support plate (5), and a sealed cavity (6), wherein: The Rs test seat comprises an Rs test cavity (1), a dielectric column assembly (2), and an annular metal film (3); an input coupling structure (10) and an output coupling structure (11) are symmetrically arranged on both sides of the Rs test cavity (1); the dielectric column assembly (2) is composed of a dielectric cylinder (201) and a dielectric disk (202) that are integrally formed and coaxially arranged; the dielectric disk (202) is located at the bottom of the dielectric cylinder (201); a concave pit is formed at the bottom end of the Rs test cavity (1); and the dielectric disk (202) is disposed at the bottom end of the dielectric cylinder (201). 02) is embedded in the pit and fixedly connected to the Rs test cavity (1), the dielectric cylinder (201) is located inside the Rs test cavity (1) and is coaxial with the Rs test cavity (1), the outer portion of the lower surface of the dielectric disk (202) is plated with an annular metal film (3), and the annular metal film (3) is concentric with the dielectric cylinder (201); the lower surface of the annular metal film (3) and the bottom end surface of the Rs test cavity (1) are in the same plane, and together constitute the test plane of the Rs test seat; The HTS film (4) to be tested is placed on the test plane of the Rs test seat and supported and fastened by a support plate (5), and the edge portion of the support plate (5) is detachably connected to the bottom end surface extension portion of the Rs test cavity (1); The calibration component is detachably placed on the test plane of the Rs test seat; The sealed cavity (6) is detachably sealed and fixed to the bottom end surface extension portion of the Rs test cavity (1), and covers the calibration component, or the support plate (5) and the HTS thin film (4) to be tested.

2. A local testing device for microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The input coupling structure (10) and the output coupling structure (11) are both coupling ring structures.

3. A local testing device for microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The calibration assembly comprises a calibration plate (7) and a calibration seat (8); the edge portion of the calibration plate (7) is detachably connected to the extension portion of the bottom end surface of the Rs test cavity (1); the calibration seat (8) has the same structure as the Rs test seat except that it does not have an input coupling structure and an output coupling structure; the calibration seat (8) and the Rs test seat are placed in an inverted and symmetrical manner relative to the test plane, and the extension portion of the calibration seat (8) is detachably connected to the extension portion of the bottom end surface of the Rs test cavity (1).

4. A local testing device for microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The specific method of fixedly connecting the medium disk (202) and the Rs test cavity (1) is welding.

5. The device for local testing of microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The thickness of the annular metal film (3) ranges from 300 nm to 1 μm, and the thickness of the dielectric disk (202) ranges from 0.2 mm to 1 mm.

6. The device for local testing of microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The annular metal film (3) is an electroplated silver dielectric film.

7. The device for local testing of microwave surface resistance of high temperature superconducting thin film according to claim 1, characterized in that: The medium disk (202) is also provided with at least one exhaust hole (9), and the exhaust hole (9) is located within a corresponding position range of the inner circle of the annular metal film (3).

8. A method for local testing of microwave surface resistance of a high-temperature superconducting film using the testing device according to any one of claims 1 to 7, comprising the following steps: Step 1: Set the microwave surface resistance to R S1 The calibration plate (7) is mounted on the test plane of the Rs test seat, so that the upper surface of the calibration plate (7) is in close contact with the annular metal film (3) of the Rs test seat, and the calibration plate (7) is sealed with a sealing chamber (6), and then the test device is placed at the working temperature of the HTS film (4) to be tested, and its quality factor Q is measured. 01 ; Step 2: Set the microwave surface resistance to R S2 = 0 is mounted on the test plane of the Rs test seat, so that the annular metal film of the calibration seat (8) is directly opposite to and closely attached to the annular metal film (3) of the Rs test seat, and the calibration seat (8) is sealed with a sealing chamber (6), and then the test device is placed at the working temperature of the HTS film (4) to be tested, and its quality factor Q is measured. 02 ; Step 3, assemble the HTS film (4) to be tested on the test plane of the Rs test seat, make the upper surface of the HTS film (4) to be tested close to the annular metal film (3) of the Rs test seat, and use the support plate (5) to support and fix the HTS film (4) to be tested, use the sealing chamber (6) to seal the HTS film (4) to be tested and the support plate (5), then place the test device at the working temperature of the HTS film (4) to be tested, and measure its quality factor Q0; Step 4: According to the formula The microwave surface resistance R of the HTS film (4) to be tested located at the corresponding part of the inner circle of the annular metal film (3) is calculated. s .

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