Controllable preparation method of high-resistance superconducting nitride film and application

Abstract

This invention discloses a controllable preparation method and application of high-resistivity superconducting nitride thin films. The method first plots a phase diagram showing the distribution of magnetron sputtering modes of the nitride thin film as a function of sputtering current and argon-nitrogen ratio. Based on the trend of sputtering voltage versus sputtering current, the magnetron sputtering modes are classified into metallic, competing, and poisoning modes. Then, a magnetron sputtering volt-ampere curve from the phase diagram is selected, and nitride thin films are grown under typical operating conditions for different magnetron sputtering modes. The distribution of the nitride thin film's crystal phase and electrical properties is observed to determine the basic operating mode for preparing high-resistivity superconducting nitride thin films. Finally, high-resistivity superconducting nitride thin films are grown according to the boundary conditions of the basic operating mode. This invention proposes a universal method for preparing high-resistivity superconducting nitride thin films. The prepared high-resistivity superconducting niobium nitride thin films exhibit significantly higher resistivity than current niobium nitride thin film materials, providing a favorable guarantee for preparing high-saturation quantum efficiency SNSPD detectors.

Description

Technical Field

[0001] This invention relates to a method for preparing and applying superconducting thin films, and more particularly to a controllable method for preparing and applying high-resistivity superconducting nitride thin films. Background Technology

[0002] Superconducting materials possess significant technological importance due to their zero-resistance properties at superconducting transition temperatures and their perfect diamagnetism. Various superconducting devices based on these materials play crucial roles in quantum computing, encrypted communication, and broadband astronomical detection. Niobium nitride (NbN), with its strong structural stability, high superconducting transition temperature (17K), and ability to operate above 2.3K, is widely used as a primary material in various superconducting devices, including superconducting nanowires single photon detectors (SNSPDs), superconducting quantum interference devices (SQUIDs), and Josephson junctions (JJs), and is extensively applied across a broadband detection spectrum from terahertz to infrared. The quality of the NbN thin film plays a critical role in the performance of these devices, and different applications demand different material characteristics of NbN (superconducting transition temperature, current density, disorder, and conductivity).

[0003] However, the lack of repeatability in controlling material parameters such as film thickness, uniformity, and resistivity during NbN growth severely limits the yield and size of devices made from such thin films. For example, superconducting single-photon detectors (SNSPDs) require a large-scale increase in the number of pixels to achieve thousands of photons and GHz-level photon detection rates. The low uniformity of thin NbN films or the limited area of ​​the superconducting active region in the film results in extremely low yields and pixel sizes for multi-pixel SNSPDs.

[0004] Meanwhile, different magnetron sputtering systems vary significantly in their internal cavity structure and sputtering target size, making the sputtering process parameters between different devices unreliable. Therefore, mature and stable niobium nitride thin film sputtering systems are difficult to replicate. This means that developing new niobium nitride sputtering systems requires experimenting with various operating parameters such as sputtering pressure, argon-nitrogen ratio, sputtering power, and target-substrate distance, as well as extensive superconducting performance measurements of thin films, consuming enormous human, material, and time resources. This severely limits the expansion of research on niobium nitride and other similar materials. Summary of the Invention

[0005] Purpose of the invention: The purpose of this invention is to provide a controllable preparation method for high-resistivity superconducting nitride thin films that is not dependent on a specific magnetron sputtering system and has universal applicability.

[0006] A second objective of this invention is to provide the application of high-resistivity superconducting nitride thin films prepared by the above method in superconducting single-photon detectors.

[0007] Technical solution: The controllable preparation method of the superconducting nitride thin film of the present invention includes the following steps:

[0008] (1) Plot the distribution phase diagram of magnetron sputtering mode of nitride thin film with sputtering current and argon-nitrogen ratio, and classify the magnetron sputtering mode into metal mode, competition mode and poisoning mode according to the trend of sputtering voltage with sputtering current.

[0009] (2) Select a magnetron sputtering voltammetry curve in the phase diagram, and grow nitride thin films under typical working conditions under different magnetron sputtering modes; observe the distribution of nitride thin film crystal phase and electrical properties, and determine the basic working mode for preparing high-resistivity superconducting nitride thin films from the three magnetron sputtering modes.

[0010] (3) Based on the boundary conditions of the basic working mode, grow high-resistivity superconducting nitride films.

[0011] Further, in step (1), under the condition of fixed discharge pressure, a phase diagram of the distribution of magnetron sputtering mode as a function of sputtering current and argon-nitrogen ratio is plotted.

[0012] Further, in step (1), when drawing the phase diagram, the process conditions for magnetron sputtering are as follows: target-substrate distance is 30-80mm, gas pressure is 0.5-8mTorr, argon flow rate is 30-120sccm, nitrogen flow rate is 2-40sccm, and DC power supply current is 0.1-3A; record the discharge voltage under the working conditions; step length is 0.5A; wait for each working condition to stabilize for 10-30s, and record the discharge voltage after stabilization.

[0013] Furthermore, in step (1), the poisoning mode is at a sputtering current of 0.2-0.6A in the phase diagram, the competition mode is at a sputtering current of 0.6-1.15A in the phase diagram, and the metal mode is at a sputtering current of 1.15-3A in the phase diagram.

[0014] Furthermore, the nitride is one of niobium nitride, aluminum nitride, or tungsten nitride.

[0015] Furthermore, when the nitride is niobium nitride, the basic working mode for preparing niobium nitride thin films is that the competing mode is close to the poisoning mode in the phase diagram, wherein the nitride thin film with a focus on metallic properties selects the metallic mode region, and the nitride thin film with a focus on non-metallic properties selects the poisoning mode region.

[0016] Furthermore, niobium nitride thin films were prepared by selecting poisoning / competitive mode boundary conditions at low sputtering power using a phase diagram.

[0017] In step (2), the conditions for selecting the basic working mode are: the thickness of the nitride film is 4-10 nm, the superconducting transition temperature is 3-15 K, and the resistivity is not less than 300 μΩcm; for nitride films with a thickness of 8 nm or more, the superconducting transition temperature is not less than 7 K; when using a silicon substrate, the superconducting transition temperature of nitride films with a thickness of 10 nm or less does not exceed 10 K.

[0018] Furthermore, in step (2), the typical working conditions are: target distance of 30-80 mm, total gas pressure of 1-6 mTorr, argon flow rate of 50-100 sccm, nitrogen flow rate of 2-10 sccm, and DC power supply current of 0.2-2.4 A.

[0019] Furthermore, in step (2), the typical operating currents under different sputtering modes are: 0.2A and 0.4A in poison mode, 0.6A, 0.8A, 0.9A and 1.1A in competition mode, and 1.2A, 1.4A and 1.65A in metal mode.

[0020] Furthermore, in step (2), when growing the nitride film, the substrate is ultrasonically cleaned in acetone, ethanol, and deionized water for a period of time to remove surface impurities. The ultrasonic power is preferably 80W.

[0021] Further, in step (2), when growing nitride films, the growth time under different working conditions is controlled to be 27.8 min, 11.1 min, 5.95 min, 3.8 min, 2.9 min, 2 min, 1.8 min, 98 s, and 77 s; and a film with a thickness of 100 nm is obtained under each condition.

[0022] Furthermore, in step (2), after growing the nitride film, the resistivity distribution of the nitride film in the three modes is obtained by using the four-probe method; the resistance change trend of the nitride film and the distribution of the superconducting transition temperature in the three modes are obtained by using liquid helium and GM refrigerator.

[0023] Furthermore, in step (2), during the growth of the nitride film, the sputtering rate under different working conditions is calibrated, specifically including the following steps:

[0024] (S1) Apply photoresist to the surface of the substrate and dry it;

[0025] (S2) Growth under different working conditions;

[0026] (S3) The substrate on which the thin film is grown is ultrasonicated for a period of time in acetone, ethanol and deionized water to remove the photoresist and the upper film to form a step.

[0027] (S4) Use a profilometer to scan the height of the thin film step.

[0028] Furthermore, in step (S1), the photoresist is az1500 and is dried at 100°C for 2 minutes; in step (S2), the growth time is controlled to be 5-30 minutes.

[0029] Further, in step (S4), the scanning distance is 0.5 mm and the scanning speed is 0.02 mm / s; the thin film growth rates obtained are 0.06 nm / s, 0.15 nm / s, 0.28 nm / s, 0.44 nm / s, 0.57 nm / s, 0.8 nm / s, 0.92 nm / s, 1.02 nm / s, and 1.3 nm / s, respectively.

[0030] Further, in step (3), the process parameters of the boundary conditions are as follows: target-substrate distance is 30-80 mm, total gas pressure is 2-5 mTorr, argon flow rate is 50-100 sccm, nitrogen flow rate is 2-10 sccm, DC power supply current is 0.2-1.6 A, discharge voltage is 322-433 V, sputtering rate is 0.05-0.5 nm / s; growth time is controlled at 20-200 s, and the thickness of the grown nitride film is 4-10 nm; wherein, the DC power supply current is more preferably 0.2-0.6 A, the discharge voltage is more preferably 362-433 V, and the growth time is more preferably 20-45 s.

[0031] This invention provides the application of high-resistivity superconducting nitride thin films prepared by the above method in superconducting single-photon detectors.

[0032] Beneficial effects: Compared with the prior art, the present invention achieves the following significant effects:

[0033] (1) This invention provides a universal method for preparing high-resistivity superconducting NbN and similar nitride thin films. This method establishes a correspondence between the specific sputtering state inside the magnetron sputtering and the material properties such as the structure, resistivity, and superconducting transition temperature of the nitride thin film through the magnetron current-voltage characteristic curve, thereby obtaining the structural phase diagram of the nitride thin film. Then, using the structural phase diagram model of the nitride thin film combined with the glow discharge principle, the sputtering mode of the magnetron sputtering instrument under specific conditions is inferred. In the phase diagram, according to the trend of sputtering voltage with sputtering current, the magnetron sputtering mode is divided into poisoning mode, competition mode, and metal mode. Then, by adjusting parameters such as argon-nitrogen ratio, discharge gas pressure, and target-substrate distance, the required sputtering mode is made to meet the process parameters that meet the power requirements. That is, the sputtering mode that enables the nitride thin film to have high resistance and high superconducting transition temperature is selected as the basic working mode. Finally, the nitride thin film with high resistance and high superconducting transition temperature can be grown under the boundary conditions of the basic working mode.

[0034] (2) For the preparation of superconducting niobium nitride thin films, by selecting the operating point at the boundary between the poisoning mode and the competition mode under low power, a high-resistivity superconducting niobium nitride thin film can be grown. This niobium nitride thin film has a resistivity that is significantly higher than that of current niobium nitride thin film materials, which provides a favorable guarantee for the preparation of SNSPD detectors with high saturation quantum efficiency.

[0035] (3) The phase diagram construction method used in this invention can be widely applied to the efficient development and maintenance of growth systems for materials similar to niobium nitride, such as aluminum nitride and tungsten nitride, and has general applicability. Attached Figure Description

[0036] Figure 1 The phase diagram of the magnetron sputtering mode constructed in step one of Example 1;

[0037] Figure 2 This is a schematic diagram of the magnetron sputtering mode constructed according to the present invention;

[0038] Figure 3 This is a current-voltage curve diagram showing the specific conditions in step two of Example 1;

[0039] Figure 4 This is a distribution diagram of the characteristic modes of the niobium nitride thin film material constructed in step three of Example 1;

[0040] Figure 5 The resistance temperature change curve of the niobium nitride thin film in step four of Example 1;

[0041] Figure 6 This is a comparison between the high-resistivity niobium nitride obtained in step six of Example 1 and the current niobium nitride resistance values. Detailed Implementation

[0042] The present invention will now be described in further detail.

[0043] Example 1

[0044] A method for preparing a high-resistivity superconducting niobium nitride thin film includes the following steps:

[0045] Step 1: Collect magnetron voltammetric characteristics under different argon-nitrogen ratios and plot the mode phase diagram of niobium nitride thin films:

[0046] The discharge pressure was fixed at a total pressure of 2 mTorr for argon and nitrogen, and the target-substrate distance was fixed at 70 mm. The argon flow rate was 100 sccm, the nitrogen flow rate was 2-20 sccm, the step length was 0.25 sccm, the DC power supply current was 0.2-3 A, and the step length was 0.5 A. Each operating condition was allowed to stabilize for approximately 15 seconds. The discharge voltage after stabilization was recorded, and the sputtering mode phase diagram of the niobium nitride thin film was plotted. The phase diagram is shown below. Figure 1 As shown.

[0047] Step 2: Determine sputtering modes based on volt-ampere characteristics:

[0048] The magnetron sputtering mode phase diagram obtained in step one includes the following three modes: poisoning mode with the target surface completely covered by NbN compound, competing mode with the target surface partially covered by NbN compound, and metallic mode with complete Nb atom sputtering. Specifically:

[0049] Combination Figure 2 In the initial stage, the current ranges from 0.2 to 0.6 A. The relatively high discharge voltage in the initial stage reflects the relatively low conductivity of the target surface. This is because the binding rate between the metal Nb atoms on the target surface and the reactant gas N2 molecules is greater than that of the discharge gas Ar. + The first stage involves the sputtering rate of Nb atoms from the target, resulting in the complete coverage of the metallic Nb target surface by NbN with a high secondary electron emission coefficient, corresponding to the magnetron sputtering poisoning mode. The second stage involves a current range of 0.6-1.15 A, during which the discharge voltage exhibits an abnormal negative growth trend. This is due to the gradually increasing Nb atom sputtering rate, the gradual reduction of the NbN coverage area on the target surface, and the overall increased conductivity of the target surface, corresponding to the competition mode. The third stage involves a current range of 1.15-3 A, where the discharge voltage growth trend is consistent with that of pure argon glow discharge. Nb atom sputtering dominates the sputtering process, and the sputtered area on the target surface is not covered by NbN, corresponding to the metallic mode.

[0050] By observing the phase diagram distribution in step one, it can be concluded that increasing the nitrogen flow rate can improve the growth competitiveness of NbN on the Nb target surface and significantly extend the negative resistance region.

[0051] Step 3: Select one of the magnetron sputtering voltammetry curves from the phase diagram obtained in Step 1, and grow a 100-nanometer thick film under typical operating conditions for different sputtering modes; specifically, this includes the following steps:

[0052] (3-1) Si / SiO2 substrate treatment: The two-inch double-sided polished Si / SiO2 substrate was ultrasonically cleaned for 5 minutes each in acetone, ethanol and deionized water with an ultrasonic power of 80W to remove surface impurities. Finally, the substrate was dried with a nitrogen gun and set aside for later use.

[0053] (3-2) Step pretreatment: Apply az1500 photoresist to the surface of the treated substrate and dry at 100°C for 2 min;

[0054] (3-3) Niobium nitride film growth: The treated substrate was placed in the magnetron sputtering chamber and the vacuum was evacuated to 8×10⁻⁶. - 4 The specific process parameters for magnetron sputtering are as follows: target-substrate distance is 70 mm, total gas pressure is 2 mTorr, argon flow rate is 100 sccm, and nitrogen flow rate is 6.5 sccm. The typical operating currents for different sputtering modes are: 0.2 A and 0.4 A in poisoning mode, 0.6 A, 0.8 A, 0.9 A, and 1.1 A in competition mode, and 1.2 A, 1.4 A, and 1.65 A in metal mode. The growth time is controlled at 30 min.

[0055] (3-4) Step preparation: The substrate of the grown film was ultrasonicated for 5 min each in acetone, ethanol and deionized water with an ultrasonic power of 80W to remove the az1500 photoresist and the upper film to form a step, and then dried with a nitrogen gun and waited for the step test.

[0056] (3-5) Growth rate measurement: The height of the thin film step was scanned using a profilometer at a scanning distance of 0.5 mm and a scanning speed of 0.02 mm / s; the thin film growth rates obtained were 0.06 nm / s, 0.15 nm / s, 0.28 nm / s, 0.44 nm / s, 0.57 nm / s, 0.8 nm / s, 0.92 nm / s, 1.02 nm / s, and 1.3 nm / s, respectively.

[0057] (3-6) Growth of 100 nm niobium nitride film: The magnetron sputtering process parameters are as in step (3-3), and the growth time under different working conditions is controlled to be 27.8 min, 11.1 min, 5.95 min, 3.8 min, 2.9 min, 2 min, 1.8 min, 98 s, and 77 s; 100 nm thick film is obtained under each condition.

[0058] Step 4: Test the electrical properties of the 100nm thick niobium nitride film grown under the conditions of Step 3, specifically including the following steps:

[0059] (4-1) Resistivity Measurement: The resistance of the niobium nitride film grown on a two-inch Si / SiO2 substrate was measured using a Keithlay 2450 analyzer with the four-probe method. The resistance was then multiplied by a two-inch coefficient of 4.478 to obtain the sheet resistance. The sheet resistance was then multiplied by the actual film thickness to obtain the film resistivity. Figure 4 As shown, the thin film resistivity remains relatively high in the poisoning mode and rapidly decreases to a relatively low level in the competition mode, with a resistivity decrease of about 50% compared to the poisoning mode. The resistivity gradually increases as it approaches the metal mode and finally decreases rapidly in the metal mode.

[0060] (4-2) Superconducting transition temperature measurement: The sample wire was placed in a liquid helium container. A Keithlay 2450 analyzer was used with a 10 μA bias current applied, and the thin film bias voltage was recorded simultaneously. The thin film resistance was calculated. The temperature change of the thin film was read via serial port. The superconducting transition temperature is the temperature at which the sample resistance reaches 10%. The superconducting transition temperature of the thin film under various conditions was recorded. Figure 3 As shown, the competitive mode has the highest superconducting transition temperature, which is about 25% higher than that of the poisoned mode. In the metallic mode, the superconducting transition temperature of the thin film drops rapidly to below 2.3K.

[0061] Based on the above results, we can conclude that NbN thin films exhibit the highest superconducting transition temperature in the competing mode, making it the fundamental choice for fabricating high-performance superconducting devices. However, this does not mean that other modes have no applications; choices can be made according to specific needs.

[0062] Step 5: Verification of Experimental Results

[0063] The resistance-temperature profiles of NbN thin films sputtered at currents of 0.2A, 0.8A, and 1.1A were normalized to the resistance at 300K. Figure 5 As shown, the ratios of the thin film resistance at 20K to the room temperature resistance at 300K are 1.257, 1.082, and 1.009, respectively. The negative growth rate of the thin film resistivity with decreasing temperature gradually returns to zero from the poisoning mode to the metallic mode, indicating that the metallic phase in the thin film is gradually strengthening, which is consistent with the expectation of the actual sputtering mode inside the magnetron in step one.

[0064] Step Six: Prepare nanoscale high-resistivity NbN thin films and measure their electrical properties: This includes the following steps:

[0065] (6-1) Selection of operating point for high-resistivity superconducting NbN thin films: As shown in the results of step four, the competitive mode is the primary region for preparing superconducting thin films. Under the premise of maintaining a small change in superconducting performance, the NbN thin films grown at the operating point at the boundary between the poisoned mode and the competitive mode have both good superconducting performance and high resistivity. In addition, it is necessary to reduce the sputtering rate to ensure controllable growth of nanoscale thin films. A smaller sputtering current needs to be selected to meet the low sputtering rate requirement. Since the boundary between the poisoned mode and the competitive mode will move towards a smaller sputtering current as the argon flow rate decreases, and increasing the gas pressure can suppress the decomposition of NbN thin films during growth and improve the quality of film growth, the selected operating conditions for high-resistivity superconducting NbN are: target-substrate distance of 70 mm, total gas pressure of 4.25 mTorr, argon flow rate of 100 sccm, nitrogen flow rate of 4 sccm, DC power supply current of 0.5 A, discharge voltage of 382 V, and sputtering rate of 0.2 nm / s.

[0066] (6-2) Growth of high-resistivity superconducting NbN thin films: The substrate is treated according to the substrate treatment method in step three, and the growth is carried out according to the magnetron sputtering process parameters determined in step (6-1). The growth time is controlled to be 20s-45s and the step length is 5s. High-resistivity niobium nitride thin films are grown with thicknesses of 4nm, 5nm, 6nm, 7nm, 8nm and 9nm respectively.

[0067] (6-3) Measurement of electrical properties of high-resistivity superconducting NbN thin films: The resistivity and superconducting transition temperature of the six thin films obtained in step (6-2) were measured using the same method as in step four. The measurement results are shown in Table 1.

[0068] Example 2

[0069] Based on Example 1, but differing from Example 1, the magnetron sputtering process parameters for NbN thin film growth in step (6-2) are as follows: total gas pressure during sputtering is 2 mTorr, argon flow rate is 100 sccm, nitrogen flow rate is 2.5 sccm, DC power supply current is 0.25 A, discharge voltage is 334 V, sputtering rate is 0.093 nm / s, growth time is controlled at 80 s, and the thickness of the grown niobium nitride thin film is 8.2 nm. The electrical properties of the thin film are measured as shown in Table 1.

[0070] Example 3

[0071] Based on Example 1, but differing from Example 1, the magnetron sputtering process parameters for NbN thin film growth in step (6-2) are as follows: total gas pressure during sputtering is 4.25 mTorr, argon flow rate is 100 sccm, nitrogen flow rate is 10 sccm, DC power supply current is 1.2 A, discharge voltage is 420 V, sputtering rate is 0.48 nm / s, growth time is controlled at 16.6 s, and the thickness of the grown niobium nitride thin film is 8.1 nm. The electrical properties of the thin film are measured as shown in Table 1.

[0072] Comparative Example 1

[0073] Based on Example 1, but differing from Example 1 in that, in step (6-1), the selected NbN operating conditions are: selecting the operating point within the competition mode; in step (6-2), the magnetron sputtering process conditions for NbN thin film growth are: total gas pressure of 4.25 mTorr, argon flow rate of 100 sccm, nitrogen flow rate of 4 sccm, DC power supply current of 1 A, discharge voltage of 368 V, sputtering rate of 0.513 nm / s, controlled growth time of 17 s, and niobium nitride thin film thickness of 8.4 nm. The electrical performance measurement results of the thin film are shown in Table 1.

[0074] Table 1. Low-temperature measurement data of niobium nitride thin films prepared in Examples 1-3 and Comparative Example 1.

[0075]

[0076]

[0077] As shown in Table 1, the sputtering rate of Example 2 was reduced by about half compared to Example 1. However, due to the lower working pressure, the NbN film may decompose during the growth process. The superconducting transition temperature and resistivity of the prepared 8nm film were lower than those of Example 1.

[0078] Example 3 uses the same working gas pressure as Example 1, but due to the higher nitrogen flow rate, it has higher sputtering power in both poisoning and competition modes. The sputtering rate is about 1.5 times higher than that in Example 1, and the superconducting transition temperature and resistivity of the prepared 8nm thin film are lower than those in Example 1.

[0079] Comparative Example 1 uses the same working gas pressure as Example 1, but selects the working point in competitive mode. The sputtering rate is increased by about 1.5 times compared to Example 1. The superconducting transition temperature of the prepared 8nm thin film is increased by 0.17K compared to the 8nm thin film of Example 1, and the resistivity is reduced by about half compared to Example 1.

[0080] The test results shown in Table 1 indicate that the magnetron sputtering process parameters determined in Example 1 are the optimal conditions for low-rate sputtering of high-resistivity superconducting niobium nitride thin films. Figure 6 As shown, the resistivity of the grown high-resistivity superconducting niobium nitride thin film is significantly higher than that of the current niobium nitride thin film.

Claims

1. A controllable preparation method of high resistance superconducting nitride thin films, characterized in that, The method comprises the following steps: a phase diagram of the magnetron sputtering mode of the nitride film varying with the sputtering current and the argon-nitrogen ratio is drawn, and the magnetron sputtering mode is divided into a metal mode, a competition mode and a poisoning mode according to the variation trend of the sputtering voltage with the sputtering current; when the phase diagram is drawn, the process conditions of the magnetron sputtering are as follows: the target-substrate distance is 30-80 mm, the gas pressure is 0.5-8 mTorr, the argon flow rate is 30-120 sccm, the nitrogen flow rate is 2-40 sccm, and the direct current of the direct current power supply is 0.1-3 A; and the discharge voltage under the working conditions is recorded; (2) one magnetron sputtering volt-ampere curve in the phase diagram is selected, and the nitride film is grown under typical working conditions in different magnetron sputtering modes; the crystal phase and the electrical property distribution of the nitride film are observed, and the basic working mode for preparing the high-resistance superconducting nitride film is determined from the three magnetron sputtering modes; the conditions of the basic working mode are as follows: the thickness of the nitride film is 4-10 nm, the superconducting transition temperature is 3-15 K, and the resistivity is not less than 300 μΩ·cm; (3) the high-resistance superconducting nitride film is grown according to the boundary conditions of the basic working mode; The nitride is niobium nitride, and the basic working mode for preparing the niobium nitride film is the region in which the competition mode is close to the poisoning mode in the phase diagram, wherein the metal mode region is selected for the nitride film with emphasis on metal property, and the poisoning mode region is selected for the nitride film with emphasis on non-metal property.

2. The method of claim 1, wherein the method is controllable. In step (2), the typical working conditions are as follows: the target-substrate distance is 30-80 mm, the total gas pressure is 1-6 mTorr, the argon flow rate is 50-100 sccm, the nitrogen flow rate is 2-10 sccm, and the direct current of the direct current power supply is 0.2-2.4 A.

3. The method of claim 1, wherein the method is controllable. The niobium nitride film is prepared by growing in the poisoning mode / competition mode boundary conditions at a low sputtering power selected by the phase diagram.

4. The method of claim 3, wherein the method is controllable. The process parameters of the boundary conditions are as follows: the target-substrate distance is 30-80 mm, the total gas pressure is 2-5 mTorr, the argon flow rate is 50-100 sccm, the nitrogen flow rate is 2-10 sccm, the direct current of the direct current power supply is 0.2-1.6 A, the discharge voltage is 322-433 V, and the sputtering rate is 0.05-0.5 nm / s; the growth time is controlled to be 20-200 s, and the thickness of the grown nitride film is 4-10 nm.

5. The method of claim 1, wherein the method is controllable. In step (1), the poisoning mode is at a sputtering current of 0.2-0.6 A in the phase diagram, the competition mode is at a sputtering current of 0.6-1.15 A in the phase diagram, and the metal mode is at a sputtering current of 1.15-3 A in the phase diagram.

6. Application of the high-resistance superconducting nitride film prepared by the method of claim 1 to a superconducting single-photon detector.

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