Superconducting strip photonic detection device, preparation method and photonic detection system

Abstract

The application provides a superconducting strip photon detection device, a preparation method and a photon detection system, and comprises a superconducting nanowire and a first resistor, wherein the first resistor is connected in parallel to two ends of the superconducting nanowire. Under a bias current, due to the shunt of the parallel resistor, the superconducting nanowire can quickly recover from a resistance state to a superconducting state after receiving photons or interference, and will not be in a resistance state due to excessively high current, thereby preventing the device from being locked and unable to work. The preparation method of the superconducting strip photon detection device is simple to operate. When the parallel resistor is manufactured, the sidewall formed by atomic redeposition at the edge of the pattern during electron beam etching naturally becomes a vertical wire for connecting the resistor and the nanowire, so that it is not necessary to additionally grow a connecting wire. The nanowire parallel resistor forms a constant voltage source bias circuit, and naturally achieves the purpose of photon detection without locking, has low cost and high yield.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical detection technology, in particular to a superconducting strip photon detection device, a preparation method and a photon detection system. BACKGROUND

[0002] The superconducting strip photon detection device (SSPD) is an important optical detector, which can realize single photon detection from visible light to infrared band. The material used in the light-sensitive effective area is a superconducting material, generally NbN superconducting ultra-thin film, which is in the shape of nanowire strip. The wire structure is generally a meandering structure, and the effective area is about several microns to several hundred microns, as shown in Figure 1 .

[0003] The SSPD is placed in a low-temperature environment (<4K) when working, the device is in a superconducting state, and a certain bias current I b is applied. The bias current I b is slightly less than the critical current I c of the device. When a single photon is incident on the nanowire strip in the device, the superconducting Cooper pair will be broken, a large number of hot electrons will be formed, and a local hot spot will be formed. The hot spot diffuses due to Joule heat under the action of the bias current I b , and finally makes the nanowire strip locally lose superconductivity to form a resistance region. After that, the energy of the hot electrons is transmitted and relaxed through electron-phonon interaction, and then re-paired into Cooper pairs, so that the nanowire strip enters the superconducting state again. Since the thermal relaxation time of the superconducting material is very short, when the SSPD receives a single photon, a rapid electrical pulse signal will be generated at both ends of the device, thereby realizing the detection function of a single photon.

[0004] As shown in Figure 2 , the voltage source 11 and the resistor 12 are connected in series to provide a bias current I b for the superconducting strip photon detection device 13. When the voltage provided by the voltage source 11 is constant, even if the resistance of the superconducting strip photon detection device 13 changes, as long as its resistance is much smaller than the resistance value of the resistor 12, the current flowing through the superconducting strip photon detection device 13 can be considered to remain basically unchanged, that is, the superconducting strip photon detection device 13 works under constant current source bias. However, when the bias current I b is very close to the critical current I c , environmental interference can cause the current on the superconducting strip photon detection device 13 to rapidly exceed the critical current I c , and the nanowire strip becomes a resistance state and is difficult to recover to the superconducting state to detect photons again, that is, it enters the "latch" state.

[0005] Therefore, how to improve the anti-interference ability of the SSPD and solve the problem of "latching" has become one of the problems to be solved by the person skilled in the art.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of clearly and completely describing the technical scheme of the present application and facilitating the understanding of the person skilled in the art. The above technical scheme cannot be considered as known to the person skilled in the art only because it is described in the background section of the present application. SUMMARY

[0007] In view of the above-mentioned defects of the prior art, the purpose of the present application is to provide a superconducting strip photon detection device, a preparation method and a photon detection system, which are used to solve the problem that the SSPD is easily interfered and enters the "latching" state during operation, resulting in the problem that the SSPD cannot work normally.

[0008] To achieve the above-mentioned purpose and other related purposes, the present application provides a superconducting strip photon detection device, which at least comprises:

[0009] a superconducting nanowire and a first resistor, wherein the first resistor is connected in parallel to both ends of the superconducting nanowire.

[0010] Optionally, the first resistor is formed on a substrate, the superconducting nanowire is formed above the first resistor, and an insulating layer is arranged between the superconducting nanowire and the first resistor, and the first resistor and the superconducting nanowire are connected in parallel through a metal sidewall in the insulating layer.

[0011] More optionally, the material of the first resistor is metal.

[0012] More optionally, the material of the first resistor is Ti, Au, Al, Mo or Pd, or other materials that can be used to make a resistor.

[0013] More optionally, the material of the metal sidewall is the same as the material of the first resistor.

[0014] More optionally, the resistance value of the first resistor is 10Ω-90Ω.

[0015] Optionally, the material of the superconducting nanowire is NbN, Nb, TaN, NbTiN or WSi, or other superconducting materials.

[0016] Optionally, the width of the superconducting nanowire is 10nm-500nm, and the thickness of the superconducting nanowire is 1nm-20nm.

[0017] To achieve the above object and other related objects, the present application further provides a preparation method of the superconducting strip photon detection device, which at least comprises:

[0018] 1) providing a substrate, growing a metal layer on the substrate, making a mask of a first resistance pattern on the metal layer, the mask covering the pattern area of the first resistance, etching the metal layer outside the pattern area of the first resistance by ion beam to form the first resistance, and forming a metal side wall on the first resistance and the side of the mask by sputtering metal ions;

[0019] 2) growing the insulating layer after removing the mask;

[0020] 3) grinding the upper surface of the structure obtained in step 2) to thin the insulating layer and make the upper end surface of the metal side wall flush with the upper end surface of the insulating layer;

[0021] 4) growing a superconducting thin film on the surface of the structure obtained in step 3), etching the superconducting thin film to obtain a superconducting nanowire, and electrically connecting the two end electrodes of the superconducting nanowire with the upper end surface of the metal side wall.

[0022] To achieve the above object and other related objects, the present application further provides a photon detection system, which at least comprises:

[0023] a voltage source, a second resistance, a bias tee, a photon counter and the superconducting strip photon detection device described above, the superconducting strip photon detection device being arranged in a low-temperature environment;

[0024] the second resistance being connected between the voltage source and the direct current end of the bias tee for providing a direct current bias;

[0025] one end of the superconducting strip photon detection device being connected to the direct current radio frequency end of the bias tee, the other end being grounded, receiving the direct current bias, and realizing single-photon detection based on the direct current bias;

[0026] the photon counter being connected to the radio frequency end of the bias tee, receiving the electric pulse signal output by the superconducting strip photon detection device, and counting the electric pulse signal.

[0027] Optionally, the photon detection system further comprises an amplifier arranged between the bias tee and the photon counter, for amplifying the electric pulse signal input into the photon counter.

[0028] More optionally, the resistance value of the second resistance is 1000 times to 10000 times of the resistance value of the first resistance in the superconducting strip photon detection device.

[0029] The superconducting strip photon detection device, the preparation method and the photon detection system have the following beneficial effects:

[0030] 1、The superconducting strip photon detection device of the application has parallel resistances at both ends of the superconducting nanowire, so that the superconducting nanowire works in a constant voltage source bias mode, thereby stabilizing the voltage at both ends of the nanowire and avoiding entering a "latch" state, and the anti-interference ability of the superconducting strip photon detection device is improved.

[0031] 2、The first resistance in the superconducting strip photon detection device of the application is connected in parallel with the superconducting nanowire through a metal side wall, the metal side wall is naturally formed by sputtering metal ions at the edge of a pattern when etching a metal layer where the first resistance is located, and no additional process step is added, so that the preparation method is simple and the cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A structure schematic diagram of a nanowire strip in the prior art is shown.

[0033] Figure 2 A working principle schematic diagram of a superconducting strip photon detection device in the prior art is shown.

[0034] Figure 3 A structure schematic diagram of the superconducting strip photon detection device of the application is shown.

[0035] Figure 4 A cross-sectional structure schematic diagram of the superconducting strip photon detection device of the application integrated on a chip is shown.

[0036] Figure 5 A scanning electron microscope picture of the parallel connection achieved by the metal side wall connection mode of the application is shown.

[0037] Figure 6 A structure schematic diagram of the preparation method of the superconducting strip photon detection device of the application for forming a substrate, a metal layer and a mask is shown.

[0038] Figure 7 A principle schematic diagram of the preparation method of the superconducting strip photon detection device of the application for forming a metal side wall is shown.

[0039] Figure 8 A structure schematic diagram of the preparation method of the superconducting strip photon detection device of the application for forming a metal side wall is shown.

[0040] Figure 9 A structure schematic diagram of the preparation method of the superconducting strip photon detection device of the application for growing an insulating layer is shown.

[0041] Figure 10 A structure schematic diagram of the preparation method of the superconducting strip photon detection device of the application for forming an insulating layer is shown.

[0042] Figure 11 shows a structural schematic diagram of a photon detection system of the present application.

[0043] Element number explanation

[0044] 11 voltage source

[0045] 12 resistor

[0046] 13 superconducting strip photon detection device

[0047] 2 superconducting strip photon detection device

[0048] 21 superconducting nanowire

[0049] 22 first resistor

[0050] 22a metal layer

[0051] 23 substrate

[0052] 24 metal side wall

[0053] 25 insulating layer

[0054] 26 mask

[0055] 3 voltage source

[0056] 4 second resistor

[0057] 5 bias tee

[0058] 6 photon counter

[0059] 7 amplifier DETAILED DESCRIPTION

[0060] The present application is described below by way of specific embodiments, and those skilled in the art can easily understand other advantages and effects of the present application from the disclosure of the present specification. The present application can also be implemented or applied by other different embodiments, and each detail in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present application.

[0061] Reference is made to Figures 3-11 It should be noted that the diagrams provided in the present embodiments only schematically illustrate the basic concept of the present application, and only the components related to the present application are shown in the diagrams, not the number, shape and size of the components when actually implemented. The shape, number and proportion of each component when actually implemented can be arbitrarily changed, and the layout pattern of the components can be more complex.

[0062] As Figure 3As shown, the present application provides a superconducting strip photon detection device 2, which comprises:

[0063] A superconducting nanowire 21 and a first resistor 22, wherein the first resistor 22 is connected in parallel to both ends of the superconducting nanowire 21.

[0064] Specifically, the material of the superconducting nanowire 21 includes but is not limited to NbN, Nb, TaN, NbTiN or WSi, and in this embodiment, the superconducting nanowire 21 is formed of NbN; in actual use, any material with superconducting properties is suitable for the present application, and the superconducting nanowire 21 can also adopt a stacked structure of multiple materials, which will not be described one by one here.

[0065] Specifically, as an example, the width of the superconducting nanowire 21 is 10nm-500nm, including but not limited to 60nm, 80nm, 90nm, 100nm, 115nm; the thickness of the superconducting nanowire 21 is 1nm-20nm, including but not limited to 6nm, 7.5nm, 8nm, 9.5nm. In actual use, the width and thickness of the superconducting nanowire 21 can be set as needed, not limited to this embodiment.

[0066] Specifically, as an example, the material of the first resistor 22 is metal, including but not limited to Ti, Au, Al, Mo or Pd; in actual use, any material that can exhibit resistance characteristics is suitable for the present application, not limited to this embodiment. As an example, the resistance of the first resistor 22 is set to 10Ω-90Ω, including but not limited to 30Ω, 50Ω, 60Ω, 70Ω; in actual use, the resistance of the first resistor 22 can be set as needed, as long as it can achieve "no latch" when the superconducting strip photon detection device 2 is working, not limited to this embodiment. "No latch" means that under the bias current, due to the shunt of the first resistor 22, the superconducting nanowire 21 can quickly recover from the resistance state to the superconducting state after receiving photons or interference, and will not be in the resistance state due to too high current, resulting in the superconducting strip photon detection device 2 being locked and unable to work.

[0067] As shown, Figure 3 The implementation of the first resistor 22 connected in parallel to both ends of the superconducting nanowire 21 includes but is not limited to the following two kinds: the first kind is to set the first resistor 22 in the external circuit and connect the first resistor 22 in parallel to both ends of the superconducting nanowire 21 through wires; the second kind is to integrate the superconducting nanowire 21 and the first resistor 22 on the same chip through micro-nano processing technology. The scheme of realizing parallel connection through wire connection will not be described one by one here, and the scheme of using micro-nano processing technology integration will be described in detail below.

[0068] Specifically, as shown in Figure 4 The first resistor 22 is formed on a substrate 23, the superconducting nanowire 21 is formed above the first resistor 22, and an insulating layer 25 is arranged between the superconducting nanowire 21 and the first resistor 22. The first resistor 22 and the superconducting nanowire 21 are connected in parallel through the metal sidewall 24 in the insulating layer 25, as shown in Figure 5 The scanning electron microscope picture of the parallel connection realized by the metal sidewall connection mode is shown. As an example, the material of the substrate 23 is Si, the material of the metal sidewall 24 is the same as the (metal) material of the first resistor 22, and the material of the insulating layer 25 is SiO2. In actual use, the corresponding substrate, metal sidewall, and insulating layer materials can be set as needed, and are not limited to the present embodiment.

[0069] It should be noted that in actual use, the first resistor 22 can also be arranged in the same plane as the superconducting nanowire 21 and connected in parallel through the metal wiring in the plane, which is not described here.

[0070] As shown in Figures 4-10 The present application also provides a preparation method of a superconducting strip photon detection device 2, in which the superconducting nanowire 21 and the first resistor 22 are integrated on the same chip. The preparation method of the superconducting strip photon detection device 2 comprises:

[0071] 1) A substrate 23 is provided, a metal layer 22a is grown on the substrate 23, a mask 26 of the first resistor 22 pattern is made on the metal layer 22a, the mask 26 covers the pattern area of the first resistor 21; the metal layer 22a outside the pattern area of the first resistor 22 is etched by ion beam to form the first resistor 22, and the metal sidewall 24 is formed by sputtering metal ions on the first resistor 22 and the side of the mask 26.

[0072] Specifically, the following steps are included:

[0073] 11) As shown in Figure 6 A substrate 23 is provided, and in the present embodiment, the substrate 23 is a single crystal silicon substrate. The metal layer 22a is grown on the upper surface of the substrate 23 by methods including but not limited to magnetron sputtering, electron beam evaporation, etc. In the present embodiment, the material of the metal layer 22a is Mo. An ultraviolet lithography process is used to make a mask 26 of the first resistor pattern on the metal layer 22a. The pattern of the first resistor 22 is calculated according to the required resistance size, and the mask 26 covers the pattern area of the first resistor 22.

[0074] 12) As shown in Figure 7 and Figure 8As shown, the metal layer 22a outside the patterned area of ​​the first resistor 22 is etched using an ion beam. The metal layer 22a outside the patterned area of ​​the first resistor 22 gradually thins. Simultaneously, during the ion beam etching process, metal ions sputtered from the surface of the metal layer 22a are re-deposited onto the sides of the first resistor 22 and the mask 26. After the ion beam etching is completed, the metal layer 22a outside the patterned area of ​​the first resistor 22 is removed, and a metal sidewall 24 of a certain thickness is naturally formed on the sides of the first resistor 22 and the mask 26. The thickness of the metal sidewall 24 is sufficient to achieve electrical connection; details are omitted here. The height of the metal sidewall 24 is greater than the thickness of the metal layer 22. For example, the height of the metal sidewall 24 is 100nm to 990nm; the actual height is determined by the energy of the sputtered metal ions, which can be changed by setting the process parameters; details are omitted here.

[0075] 2) After removing the mask 26, the insulating layer 25 is grown.

[0076] Specifically, such as Figure 9 As shown, in this embodiment, after removing the mask 26, the insulating layer 25 is grown using plasma-enhanced chemical vapor deposition (PECVD). The insulating layer 25 is made of SiO2. As an example, the thickness of the insulating layer 25 is 100 nm to 990 nm. In this embodiment, the thickness of the insulating layer 25 is greater than the height of the metal sidewall 24.

[0077] 3) Grind the upper surface of the structure obtained in step 2) to thin the insulating layer 25 and reduce the height of the sidewall to achieve the required insulating layer thickness and make the upper end face of the metal sidewall 24 flush with the upper end face of the insulating layer.

[0078] Specifically, such as Figure 10 As shown, the structure obtained in step 2) is polished using chemical mechanical polishing. Figure 9 The upper surface is polished to the required thickness of the insulating layer 25, which is typically λ / 4 (λ is the wavelength of the light detection) to improve light absorption. Simultaneously, after polishing, the upper end of the metal sidewall 24 is also partially ground down, exposing it and making it flush with the upper surface of the insulating layer 25.

[0079] 4) A superconducting thin film is grown on the surface of the structure obtained in step 3), and the superconducting thin film is etched to obtain a superconducting nanowire 21. The electrodes at both ends of the superconducting nanowire 21 are electrically connected to the upper end face of the metal sidewall 24.

[0080] Specifically, such asFigure 4 In the embodiment, a superconducting thin film is grown on the upper surface of the insulating layer 25 by a magnetron sputtering method; a mask of the superconducting nanowire 21 is made by electron beam exposure, and the superconducting nanowire 21 (including electrodes at both ends of the superconducting nanowire 21) is etched by a reactive ion etching process under the protection of the mask of the superconducting nanowire 21.

[0081] It should be noted that the various growth processes in the embodiment are examples, and in actual use, a corresponding growth process can be selected as needed, and the embodiment is not limiting. The present application realizes the electrical connection of the superconducting nanowire and the resistor by etching the resistor on the metal layer by an ion beam and connecting the two ends of the superconducting nanowire in the upper layer with the metal sidewall naturally formed at the edge of the resistor pattern during etching, so that the electrical connection of the two is realized without additional photolithography and etching on the insulating layer between the metal layer and the superconducting layer, and a latch-free superconducting strip photon detection device is simply formed, the process steps are simplified, and the yield is improved.

[0082] As shown in Figure 11 The present application also provides a photon detection system, which comprises:

[0083] The superconducting strip photon detection device 2, the voltage source 3, the second resistor 4, the bias tee 5, and the photon counter 6 are arranged in a low-temperature environment.

[0084] Specifically, as shown in Figure 11 The voltage source 3 is used to provide a constant voltage, the second resistor 4 is connected between the voltage source 3 and the direct current end of the bias tee 5, the second resistor 4 converts the voltage into a bias current (provides a direct current bias for the superconducting strip photon detection device 2) and transmits it to the superconducting strip photon detection device 2 through the bias tee 5. In the embodiment, the resistance value of the second resistor 4 is 1000 to 10000 times the resistance value of the first resistor 22 in the superconducting strip photon detection device 2. In actual use, the multiple relationship of the second resistor 4 and the first resistor 22 can be set as needed, the resistance value of the second resistor 4 is greater than the resistance value of the first resistor 22, and when disturbed, the voltage on the first resistor 22 can be basically kept unchanged, and the superconducting strip photon detection device 2 can remain in a "latch-free" state.

[0085] Specifically, one end of the superconducting strip photon detection device 2 is connected to the direct current radio frequency end of the bias tee 5, and the other end is grounded. The superconducting strip photon detection device 2 receives the bias current based on the direct current radio frequency end of the bias tee 5, and realizes single photon detection based on the bias current, and generates a fast electrical pulse signal at both ends of the superconducting strip photon detection device 2 after detecting a single photon, which is transmitted to the photon counter 6 through the direct current radio frequency end of the bias tee 5. The detection principle of the superconducting strip photon detection device 2 is not described here.

[0086] Specifically, the photon counter 6 is connected to the radio frequency end of the bias tee 5, and obtains the electrical pulse signal output by the superconducting strip photon detection device 2 from the radio frequency end of the bias tee 5, and counts the electrical pulse signal.

[0087] Specifically, as shown in Figure 11 The photon detection system further includes an amplifier 7, which is arranged between the bias tee 5 and the photon counter 6, and is used to amplify the electrical pulse signal input into the photon counter 6, so as to avoid that the electrical pulse signal has too small amplitude and cannot be recognized by the photon counter 6.

[0088] As shown in Figure 11 When the first resistance 22 is much smaller than the second resistance 4, it is equivalent to a power supply with very small internal resistance to supply power to the superconducting strip photon detection device 2, and it can be approximately considered that the superconducting strip photon detection device 2 works in a constant voltage source bias circuit. Under such bias, when the superconducting strip photon detection device 2 is in a superconducting state, the current of the circuit flows to the superconducting strip photon detection device 2, the first resistance 22 does not work, and the superconducting strip photon detection device 2 can normally detect photons. When the total power supply of the circuit (which changes greatly, or the circuit is disturbed by the outside world) is large, even if the current on the superconducting nanowire 21 becomes large (larger than the critical current I c ) and loses superconductivity and becomes a resistance state, due to the existence of the first resistance 22, it is equivalent to two resistances in parallel, the current flowing through the superconducting nanowire 21 is shunted, the voltage change at both ends of the superconducting strip photon detection device 2 is small, the disturbance on the superconducting strip photon detection device 2 is also small, and the superconducting nanowire 21 can quickly recover to a superconducting state, so that the anti-interference work of the superconducting nanowire 21 is realized, that is, the "no latch" state.

[0089] In summary, the application provides a superconducting strip photon detection device, a preparation method and a photon detection system, comprising: a superconducting nanowire and a first resistance, wherein the first resistance is connected in parallel to both ends of the superconducting nanowire. The superconducting strip photon detection device of the application can quickly recover from a resistance state to a superconducting state after receiving photons or interference under a bias current due to the shunt of the parallel resistance, and will not be in a resistance state due to excessive current, resulting in device lockout and unable to work. Moreover, the preparation method of the superconducting strip photon detection device of the application is simple to operate. When the parallel resistance is made, the sidewall naturally becomes a vertical wire connecting the resistance and the nanowire during electron beam etching, so that it is not necessary to grow a connecting wire additionally. The nanowire is connected with a resistance of appropriate size to form a constant voltage source bias circuit, and naturally achieves the purpose of photon detection without lockout, with low cost and high yield. Therefore, the application effectively overcomes the shortcomings of the prior art and has high industrial utilization value.

[0090] The above embodiments only exemplarily illustrate the principles and effects of the application, and are not used to limit the application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought of the application should be covered by the claims of the application.

Claims

1. A photon detection system, characterized by, The photon detection system at least comprises: a voltage source, a second resistor, a bias tee, a photon counter and a superconducting strip photon detector device, wherein the superconducting strip photon detector device is arranged in a low-temperature environment; the second resistor is connected between the voltage source and the direct current end of the bias tee, and is used to provide a direct current bias; one end of the superconducting strip photon detector device is connected to the direct current radio frequency end of the bias tee, and the other end is grounded, so as to receive the direct current bias and realize single-photon detection based on the direct current bias; the superconducting strip photon detector device comprises a superconducting nanowire and a first resistor, wherein the first resistor is connected in parallel to both ends of the superconducting nanowire, and is used to realize latch-free operation of the superconducting strip photon detector device; the resistance value of the second resistor is 1000 times to 10000 times of the resistance value of the first resistor; the first resistor is formed on a substrate, the superconducting nanowire is formed above the first resistor, and an insulating layer is arranged between the superconducting nanowire and the first resistor, and the first resistor and the superconducting nanowire are connected in parallel through a metal sidewall in the insulating layer; the photon counter is connected to the radio frequency end of the bias tee, and is used to receive an electrical pulse signal output by the superconducting strip photon detector device and count the electrical pulse signal.

2. The photon detection system of claim 1, wherein: The photon detection system further comprises an amplifier arranged between the bias tee and the photon counter, and used to amplify the electrical pulse signal input into the photon counter.

3. The photon detection system of claim 1, wherein: The material of the first resistor is metal.

4. The photon detection system of claim 3, wherein: The material of the first resistor is Ti, Au, Al, Mo or Pd.

5. The photon detection system of claim 3 or 4, wherein: The material of the metal sidewall is the same as that of the first resistor.

6. The photon detection system of claim 1, wherein: The resistance value of the first resistor is 10Ω to 90Ω.

7. The photon detection system of claim 1, wherein: The material of the superconducting nanowire is NbN, Nb, TaN, NbTiN or WSi.

8. The photon detection system of claim 1, wherein: The width of the superconducting nanowire is 10nm to 500nm, and the thickness of the superconducting nanowire is 1nm to 20nm.

9. A method of fabricating a superconducting strip photonic detector device in a photonic detection system as claimed in any one of claims 1-8, characterized in that, The preparation method of the superconducting strip photon detector device at least comprises: 1) providing a substrate, growing a metal layer on the substrate, making a mask of a first resistor pattern on the metal layer, and covering the pattern area of the first resistor with the mask; ion beam etching the metal layer outside the pattern area of the first resistor to form the first resistor, and forming a metal sidewall on the first resistor and the side of the mask through sputtering metal ions; 2) growing the insulating layer after removing the mask; 3) grinding the upper surface of the structure obtained in step 2) to thin the insulating layer and make the upper end surface of the metal sidewall flush with the upper end surface of the insulating layer; 4) growing a superconducting thin film on the surface of the structure obtained in step 3), etching the superconducting thin film to obtain a superconducting nanowire, and electrically connecting both ends of the superconducting nanowire to the upper end surface of the metal sidewall.

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